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Kinds of Cent Selected AbstractsA comparative study on cost and life-cycle analysis for 100,MW very large-scale PV (VLS-PV) systems in deserts using m-Si, a-Si, CdTe, and CIS modulesPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 1 2008Masakazu Ito Abstract This paper is a study of comparisons between five types of 100,MW Very Large-Scale Photovoltaic Power Generation (VLS-PV) Systems, from economic and environmental viewpoints. The authors designed VLS-PV systems using typical PV modules of multi-crystalline silicon (12·8% efficiency), high efficiency multi-crystalline silicon (15·8%), amorphous silicon (6·9%), cadmium tellurium (9·0%), and copper indium selenium (11·0%), and evaluated them by Life-Cycle Analysis (LCA). Cost, energy requirement, and CO2 emissions were calculated. In addition, the authors evaluated generation cost, energy payback time (EPT), and CO2 emission rates. As a result, it was found that the EPT is 1·5,2·5 years and the CO2 emission rate is 9,16,g-C/kWh. The generation cost was 11,12 US Cent/kWh on using 2 USD/W PV modules, and 19,20 US Cent/kWh on using 4 USD/W PV module price. Copyright © 2007 John Wiley & Sons, Ltd. [source] My Two Cents on RadiationACADEMIC EMERGENCY MEDICINE, Issue 1 2009Boris D. Veysman MD No abstract is available for this article. [source] Agricultural and Rural Development in China: Achievements and Challenges Entwicklung der Landwirtschaft und des ländlichen Raums in China: Erfolge und Herausforderungen Le développement agricole et rural en Chine : résultats et défisEUROCHOICES, Issue 2 2009Chen Xiaohua Summary Agricultural and Rural Development in China: Achievements and Challenges China has made great advances in its agricultural and rural development since the reforms and opening-up that began in 1978. It has not only fed its population of 1.3 billion, but has also contributed to international agricultural development and food security. Agricultural production registered great development, providing sufficient food and clothes for 21 per cent of the world's population with 9 per cent of the arable land. In the process farmers' living standards improved remarkably and rural public utilities and services were greatly enhanced. China is now in a key transition period of accelerating the transformation and modernisation of traditional agriculture and rural society. It is facing significant challenges. Agriculture is still one of the weakest industries in China and it is proving difficult to sustain increases in grain output and farmers' incomes. The problems of uneven development in rural areas have become increasingly prominent and the gap between urban and rural development is tending to widen. The Chinese government will respond strategically to these challenges and will firmly pursue the construction of a new efficient and sustainable socialist countryside, along the path of modernisation with Chinese characteristics. It will also make greater contributions to world agriculture and rural development. Les progrès de la Chine en termes de développement agricole et rural depuis le début des réformes et l'ouverture en 1978 ont été considérables. Non seulement le pays a nourrit une population de 1.3 millions d'habitants mais il a contribué au développement et à la sécurité alimentaire au niveau international. La production agricole a fortement augmenté et a fournit suffisamment de nourriture et de vêtements à 21 pour cent de la population du monde avec 9 pour cent des terres cultivables. Ce processus s'est accompagné d'une hausse considérable du niveau de vie des agriculteurs et d'une grande amélioration des services publics dans les zones rurales. La Chine est maintenant à un moment clé de sa période de transition, caractérisé par une accélération de la transformation et de la modernisation de l'agriculture et de la société rurale traditionnelles. Des défis importants se présentent à elle. L'agriculture reste une des industries chinoises les plus fragiles et il se révèle difficile de continuer à augmenter la production céréalière et les revenus des agriculteurs. Les problèmes d'inégalité de développement dans les zones rurales deviennent de plus en plus visibles et l'écart de développement entre les zones urbaines et les zones rurale tend à s'accroître. Les pouvoirs publics chinois vont apporter une réponse stratégique à ces défis et vont poursuivre fermement la construction d'une nouvelle campagne socialiste efficace et durable, en suivant une voie de modernisation typiquement chinoise. Ils vont aussi accroître les contributions de la Chine au développement agricole et rural mondial. Seit Beginn der Reformen und der Öffnungspolitik 1978 hat sich Chinas Landwirtschaft und ländlicher Raum enorm weiterentwickelt. China hat seitdem nicht nur seine 1.3 Milliarden Einwohner ernährt, sondern auch zur internationalen Agrarentwicklung und Ernährungssicherung beigetragen. Die Agrarproduktion wurde erheblich ausgeweitet und deckt nun 21 Prozent des weltweiten Bedarfs an Lebensmitteln und Kleidung bei gerade einmal 9 Prozent der Weltackerfläche. Dabei haben sich die Lebensbedingungen für die Landwirte sowie das Angebot an öffentlichen Einrichtungen und Dienstleistungen im ländlichen Raum deutlich verbessert. China durchläuft gerade eine wichtige Übergangsphase, in der sich der Wandel und die Modernisierung der traditionellen Landwirtschaft und der Landbevölkerung noch schneller vollziehen, und steht großen Herausforderungen gegenüber. Die Landwirtschaft ist nach wie vor einer der schwächsten Sektoren in China, und es erweist sich als schwierig, die Steigerungsraten bei der Getreideerzeugung und den Einkommen in der Landwirtschaft aufrecht zu erhalten. Die Probleme der ungleichmäßigen Entwicklung in ländlichen Gebieten werden immer offensichtlicher, und die Kluft zwischen städtischer und ländlicher Entwicklung droht sich auszuweiten. Die chinesische Regierung wird diesen Herausforderungen strategisch begegnen und , ganz im Sinne einer Modernisierung mit chinesischen Merkmalen , daran festhalten, einen neuen sozialistischen ländlichen Raum effizient und nachhaltig zu gestalten. Sie wird ebenfalls einen noch größeren Beitrag zur Weltlandwirtschaft und zur Entwicklung des ländlichen Raums leisten. [source] Self-care versus self-harm: piercing, tattooing, and self-injuring in eating disordersEUROPEAN EATING DISORDERS REVIEW, Issue 1 2005Laurence Claes Abstract Eating disordered patients seem to have a love,hate relationship with their bodies. Why do some decorate their bodies by means of tattooing and piercing, while others deliberately injure themselves and make parts of their body unattractive? We have explored this question in 101 eating-disordered patients by means of self-reporting questionnaires about the presence and characteristics of tattooing, piercing and self-injuring as well as the underlying motives. Furthermore, we studied the co-occurrence of impulsive behaviours as well as personality traits. In our patient sample, 11.9,per,cent had one or more tattoos, 25.7,per,cent a piercing and 64.9,per,cent showed some form of self-injurious behaviour (SIB). Tattooing and piercing are clearly driven by esthetical reasons, whereas SIB can have various explanations. All three behaviours were significantly more often linked to substance (ab)use. With respect to personality traits, piercing was positively linked to extraversion (positive affectivity) and openness, and negatively to conscientiousness. SIB, on the contrary, was positively linked to neuroticism (negative affectivity) and conscientiousness, and negatively to extraversion and openness. Tattooing did not show significant correlations with particular personality traits (probably due to the small number of tattooed patients). In summary, piercing and tattooing seem to reflect more self-care, and might protect some patients against more self-harm. Copyright © 2005 John Wiley & Sons, Ltd and Eating Disorders Association. [source] Changes in Mini Mental State Examination score after stroke: lacunar infarction predicts cognitive declineEUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2006P. Appelros Stroke and cognitive impairment are inter-related. The purpose of this study was to show the natural evolution of cognitive performance during the first year after a stroke, and to show which factors that predict cognitive decline. Subjects were patients with a first-ever stroke who were treated in a stroke unit. A total of 160 patients were included. At baseline patients were evaluated with regard to stroke type, stroke severity, pre-stroke dementia and other risk factors. Mini Mental State Examinations (MMSE) were performed after 1 week and after 1 year. Patients had a median increase of 1 point (range ,8 to +9) on the MMSE. Thirty-two pre cent of the patients deteriorated, 13% were unchanged, and 55% improved. Lacunar infarction (LI) and left-sided stroke were associated with a failure to exhibit improvement. Patients with LI had an average decline of 1.7 points, whilst patients with other stroke types had an average increase of 1.8 points. Most stroke survivors improve cognitively during the first year after the event. The outcome for LI patients is worse, which suggests that LI may serve as a marker for concomitant processes that cause cognitive decline. [source] International Labour Migrants' Return to Meiji-era Yamaguchi and Hiroshima: Economic and Social EffectsINTERNATIONAL MIGRATION, Issue 3 2008Jonathan Dresner International labour migration from Meiji era (1868,1912) Japan was intensely concentrated: over 60 per cent of the 29,000 participants in the government-managed Hawai'i emigration programme (kan'yaku imin, 1885,1894) came from seven coastal counties around the Hiroshima-Yamaguchi prefectural border in southwest Japan. Almost half of the emigrants became long-term settlers instead of returning to their hometowns, but this paper examines what happened to returning emigrants and to their home communities. Since the migration was primarily economic in nature, the effect of migrant earnings was carefully monitored and is frequently cited by scholars. Surveys showed high rates of debt repayment and savings, and improved living conditions, but investment and entrepreneurship were limited. High-emigration regions rarely became economic centers of any importance. Less carefully studied are non-economic effects, partially because the labour programme was structured to minimize contact with Hawaiian or Caucasian culture, and thus returnees had little cultural experience to transfer to their hometowns. Local officials in Yamaguchi seemed proud of the lack of social change. Even long-term sojourners, who returned due to family needs after a decade or more overseas, exhibited no readjustment difficulties. Returnees, particularly in Yamaguchi, sometimes moved on to Japanese colonial territories, creating multilateral and complex relationships with overseas communities. This sojourning migration, like contemporary analogs, was a powerful form of poverty relief in the midst of dislocating globalization, but did not produce a rise in entrepreneurship or a Westernization of local culture. Because this sojourning migration was structurally similar to our modern-day patterns, it provides evidence of the longevity of those patterns and the possible long-term effects, and raises questions about our expectations for migration policy. Retour des travailleurs migrants internationaux de l'ère Meiji à Yamaguchi et Hiroshima: effets économiques et sociaux Au Japon, la migration internationale de main-d',uvre de l'ère Meiji (1868,1912) a été très concentrée: plus de soixante pour cent des 29 000 participants au programme gouvernemental d'émigration à destination d'Hawaï (kan'yaku imin, 1885-1894) venaient de sept régions côtières proches de la limite entre les préfectures d'Hiroshima et de Yamaguchi dans le Sud-Ouest du Japon. Sachant que la moitié des émigrants sont devenus des résidents de longue durée et ne sont pas rentrés dans leur communauté d'origine, le présent document s'intéresse à ceux qui ont fait le choix inverse. Etant donné que cette migration était principalement de nature économique, les effets des gains des migrants ont étéétudiés avec attention et sont souvent cités par les chercheurs. Si des enquêtes ont révélé des taux importants de remboursement de dettes et d'épargne, ainsi qu'un niveau de vie en hausse, les investissements et la création d'entreprises, en revanche, sont restés limités. On a rarement vu des régions à fort taux d'émigration devenir des centres économiques d'importance. Les effets non économiques ont été moins étudiés, en partie parce que ce programme de main-d',uvre était structuré de façon à réduire le plus possible les contacts avec la culture hawaïenne ou caucasienne, ce qui fait que les rapatriés n'avaient guère d'acquis culturels exogènes à transmettre. Les responsables locaux de Yamaguchi semblaient d'ailleurs se réjouir de l'absence de changements sociaux. Même les résidents de longue durée, qui étaient rentrés pour raisons familiales au bout d'au moins une décennie à l'étranger, ne montraient aucune difficultéà se réadapter. Les rapatriés, en particulier à Yamaguchi, ont parfois déménagé vers les territoires coloniaux japonais, créant des relations multilatérales complexes avec les communautés de l'outre-mer. Cette migration temporaire, comme les mouvements analogues à la même époque, était une formidable façon de réduire la pauvreté dans un contexte de bouleversement mondial, mais elle n'a pas renforcé l'esprit d'entreprise ni conduit à une occidentalisation de la culture locale. Comme cette migration temporaire était structurellement semblable à nos modèles contemporains, elle témoigne de la longue durée de vie de ces modèles et de leurs effets possibles à long terme, et soulève des questions quant à nos attentes en matière de politique migratoire. Retorno a los trabajadores migrantes internacionales a la era Meiji en Yamaguchi e Hiroshima: Efectos socioeconómicos La migración laboral internacional en la era Meiji del Japón (1868,1912) era sumamente concentrada: más del 60 por ciento de los 29.000 participantes en el programa de emigración Hawai'i (kan'yaku imin, 1885-1894) administrado por el Gobierno, provenía de varios condados costeros en torno a la frontera prefectural entre Hiroshima-Yamaguchi en el sudeste del Japón. Casi la mitad de los emigrantes residía en albergues semipermanentes y no retornaban a sus lugares de origen. Ahora bien, en este artículo se examina lo ocurrido con los migrantes que retornaron y con las comunidades de retorno. Habida cuenta que la migración era mayormente de carácter económico, el efecto de los ingresos de los migrantes se siguió de cerca y, frecuentemente, ha sido citado por los estudiosos en la materia. Las encuestas demuestran elevadas tasas de reembolso de deudas y de ahorro, así como un mejoramiento de las condiciones de vida, pero también apuntan a limitadas inversiones o empresas. Las regiones de alta emigración rara vez se convirtieron en centros de importancia económica. No se ha estudiado en detalle los efectos extra económicos, en parte porque el programa de migración laboral estaba estructurado para minimizar el contacto con la cultura hawaiana o caucasiana, por lo cual las personas que retornaban tenían poca experiencia cultural que aportar a sus lugares de origen. Los funcionarios locales en Yamaguchi se enorgullecían de la falta de intercambio social. Incluso aquéllos residentes de larga duración que retornaron debido a cuestiones familiares tras una década o más en ultramar, no presentaron ninguna dificultad en readaptarse. Las personas que retornaron, particularmente a Yamaguchi, se desplazaron a veces a territorios coloniales japoneses, estableciendo complejas relaciones multilaterales con comunidades en ultramar. La migración de carácter permanente, al igual que sus análogos contemporáneos, era un sólido medio de aliviar la pobreza en medio de una globalización perturbadora, pero no dio lugar a un incremento empresarial o a una occidentalización de la cultura local. La similitud estructural de la migración de larga duración con nuestros patrones de hoy en día, aporta pruebas de la longevidad de los mismos, de los posibles efectos a largo plazo de dichos patrones y plantea una serie de preguntas sobre las expectativas en cuanto a las políticas migratorias. [source] On the Way to a Better Future: Belgium as Transit Country for Trafficking and Smuggling of Unaccompanied Minors1INTERNATIONAL MIGRATION, Issue 4 2005Ilse Derluyn ABSTRACT During the last decade, irregular border crossings emerged as a new element in international migratory flows, with smuggling and trafficking networks being an essential part. Many people are compelled to use these networks to realize their dream of a better living, and for many this "promised land" is the United Kingdom (UK). Belgium has important sea connections with the UK, and is, therefore, an important migration transit zone, although many migrants are intercepted on Belgian territory during their tempt to reach the UK. Some are unaccompanied or separated children and adolescents, minors travelling without parent(s) or a legal caregiver. This study aims to gain insight about this population of unaccompanied minors travelling to the UK. We use the situation in Zeebrugge, one of Belgium's main ports, as a case study. We analysed 1,093 data files of unaccompanied minors intercepted in Zeebrugge, and carried out participatory observation at the shipping police station. The intercepted unaccompanied minors are mainly male, between 15 and 18 years of age, and from an Asian or Eastern European country. Of the 899 unique persons found in the data files, 113 were intercepted several times. After the interception, the Aliens Office gives the majority (82.9%) an identity document without a requirement to leave Belgium, while 15.3 per cent must leave Belgium immediately or within five days. In 82.9 per cent of the cases, a child protection officer is contacted to make a decision about the situation. In 67.2 per cent of these cases, no child protection measure is taken, and the minor may leave the police station; in 32 per cent of the cases, the minor is transferred to a centre, mostly crisis reception. Almost all unaccompanied minors are convinced they want to reach the UK to create a better livelihood, join a family member, or escape a difficult political situation. Nevertheless, most travel in difficult circumstances; are scared; and lack essential information about life in the UK, their possibilities in Belgium, what will happen if they are transferred to a centre, and so forth. Most minors also do not want to be transferred to a centre, and many , although not all , disappear again from the centres. This study has several implications concerning the kind of decisions taken by the legal authorities, the necessary physical and psycho-social care and the availability of an interpreter and social worker during the interception, the number of reception places and the care in these centres, and the tasks of the legal guardian. Finally, some limitations of the study are mentioned. VERS UN AVENIR MEILLEUR : LA BELGIQUE COMME PAYS DE TRANSIT POUR LA TRAITE ET L'INTRODUCTION CLANDESTINE DE MINEURS NON ACCOMPAGNÉS Au cours de la dernière décennie, le franchissement irrégulier des frontières est apparu comme un nouvel élément des flux migratoires internationaux, dont les réseaux de traite et d'introduction clandestine sont un aspect essentiel. Beaucoup de gens sont forcés d'utiliser ces réseaux pour réaliser leur rêve d'une vie meilleure et pour beaucoup, cette « terre promise », c'est le Royaume-Uni. La Belgique ayant d'importantes liaisons maritimes avec le Royaume-Uni con-stitue de ce fait une importante zone de transit pour les migrations, bien que de nombreux migrants soient interceptés sur le territoire belge alors qu'ils tentent d'atteindre le Royaume-Uni. Certains d'entre eux sont des enfants et des adoles-cents non accompagnés, séparés, des mineurs qui voyagent sans parent(s), sans personne qui en ait la garde juridique. Cette étude vise à mieux connaître cette population de mineurs non accompagnés voyageant en direction du Royaume-Uni. Nous prenons comme cas concret la situation à Zeebrugge, l'un des principaux ports belges. Nous avons analysé 1 093 fichiers de données concernant des mineurs non accompagnés interceptés à Zeebrugge, et nous sommes livrés à une observation participative au poste de police du port. Les mineurs non accompagnés inter-ceptés sont pour la plupart des garçons âgés de quinze à dix-huit ans originaires d'un pays d'Asie ou d'Europe orientale. Sur les 899 personnes trouvées dans les fichiers, 113 ont été interceptées plusieurs fois. Après l'interception, les Ser-vices de l'immigration donnent à la majorité de ces garçons un document d'identité sans obligation de quitter la Belgique, alors que 15,3 pour cent d'entre eux doivent quitter le pays, soit immédiatement soit dans les cinq jours. Dans 82,9 pour cent des cas, un agent de protection de l'enfance est contacté pour prendre une décision quant à la situation. Dans 67,2 pour cent de ces cas, aucune mesure de protection de l'enfant n'est prise et le mineur peut quitter le poste de police. Dans 32 pour cent des cas, le mineur est transféré dans un centre, un lieu d'accueil pour les situations de crise. Presque tous les mineurs non accompagnés sont convaincus de vouloir se rendre au Royaume-Uni pour y gagner leur vie, retrouver un membre de leur famille ou échapper à une situation politique difficile. Pourtant, la plupart de ces mineurs voyagent dans des circonstances difficiles. Ils ont peur. Ils n'ont pas les informations essentielles sur la vie au Royaume-Uni, sur les possibilités qui existent pour eux en Belgique, sur ce qui se passera s'ils sont transférés dans un centre. Beaucoup , mais pas tous , disparaissent de ces centres. Cette étude a diverses implications concernant le genre de décisions que pren-nent les autorités juridiques, les nécessaires soins physiques et psychosociaux pendant l'interception ainsi que la présence d'un interprète et d'un travailleur social, le nombre de places et les soins dans les centres d'accueil, les tâches de la personne qui a la responsabilité légale du mineur. Enfin, certaines limites de cette étude sont évoquées. CON MIRAS A UN MEJOR FUTURO: BÉLGICA COMO PAÍS DE TRÁNSITO DE LA TRATA Y EL TRÁFICO DE MENORES NO ACOMPAÑADOS Durante la última década, los cruces fronterizos irregulares se han convertido en un nuevo elemento de las corrientes migratorias internacionales, siendo un componente esencial de ellas las redes de tráfico y trata de personas. Son muchas las personas que se ven obligadas a recurrir a estas redes para hacer realidad su sueño de una vida mejor y para muchos "la tierra prometida" es el Reino Unido. Bélgica tiene importantes conexiones marítimas con el Reino Unido y, por consi-guiente, es una zona de tránsito de la migración sumamente importante, aunque muchos migrantes son interceptados en territorio belga en su intento por llegar al Reino Unido. Entre las personas interceptadas se encuentran niños y adoles-centes, menores de edad que viajan solos, sin sus padres o tutor legal. Este estudio tiene por objeto comprender cómo esta población de menores no acom-pañados viaja al Reino Unido. Con ese fin, se recurre a un estudio por casos examinando la situación en Zeebrugge, uno de los principales puertos de Bélgica. Se han analizado 1.093 expedientes de menores no acompañados, interceptados en Zeebrugge, y se ha realizado una observación participativa en la estación de policía naval. Los menores no acompañados interceptados eran principalmente varones, entre 15 y 18 años de edad, provenientes de Asia y Europa oriental. De las 899 personas no acompañadas encontradas en los expedientes, 113 habían sido interceptadas varias veces. Tras la intercepción, el Servicio de Inmigración otorga a la mayoría un documento de identidad (82,9 por ciento) sin obligarles a abandonar Bélgica, mientras que el 15,3 por ciento debe salir inmediatamente de Bélgica, o bien en un plazo máximo de cinco días. En el 82,9 por ciento de los casos, se establece contacto con un oficial de la protección de la infancia para que decida en cuanto a la situación del menor. En el 67,2 por ciento de estos casos, no se adopta ninguna medida de protección del menor y éste puede abandonar la estación de policía; y en el 32 por ciento de los casos, se transfiere al menor a un centro de recepción que se ocupa de casos críticos. Prácticamente todos los menores no acompañados tienen la certeza de que llegarán al Reino Unido para tener una mejor vida, reunirse con un familiar, o escapar de la difícil situación política. No obstante, la mayoría viaja en condiciones difí-ciles, tiene miedo y carece de información esencial sobre la vida en el Reino Unido, sobre sus posibilidades en Bélgica, y sobre lo que ocurrirá si son trans-feridos a un centro, etc. La mayoría de estos menores no quiere ser transferida a un centro y muchos, aunque no todos, se escapan de los mismos. Este estudio repercutirá, sin lugar a dudas, en las decisiones que adoptan las autoridades jurídicas, en la atención física y sicosocial necesarias, en la disponi-bilidad de un intérprete o trabajador social durante la intercepción, así como en el número de plazas de acogida y de atención en estos centros, y en las tareas que incumben a todo tutor legal. Finalmente, se enumeran algunas de las limitaciones de este estudio. [source] A Temporal Analysis of Earnings Surprises: Profits versus LossesJOURNAL OF ACCOUNTING RESEARCH, Issue 2 2001Lawrence D. Brown I show that median earnings surprise has shifted rightward from small negative (miss analyst estimates by a small amount) to zero (meet analyst estimates exactly) to small positive (beat analyst estimates by a small amount) during the 16 years, 1984 to 1999. I show that a rightward temporal shift in median surprise from negative to positive describes earnings, but neither profits nor losses. Median profit surprise shifts within the positive quadrant, from zero to one cent per share. Median loss surprise shifts within the negative quadrant from extreme negative (about -33 cents per share) to zero. I show that the median surprise for profits exceeds that for losses in every year. I document significant positive temporal trends in both meet and beat analyst estimates for both profits and losses, but I find a greater frequency of profits that either meet or beat analyst estimates in every year. I find a significant positive temporal trend in positive profits that are "a little bit of good news," and a significant negative temporal trend in managers who report losses that are an "extreme amount of bad news." My results are robust to the four internal validity threats I consider,namely temporal changes in: (1) analyst forecast accuracy, (2) the mix of earnings of one sign preceded by earnings of another sign four quarters ago, (3) the timeliness of the most recent analyst forecast, and (4) the I/B/E/S definition of actual earnings. I find that managers of growth firms are relatively more likely than managers of value firms to report good news profits. I show that when they do report positive profit surprises, managers of growth firms are more likely to report "a little bit of good news" in every year. [source] Contemporary and historical impacts of megaherbivores on the population structure of tree euphorbias in South African subtropical thicketAFRICAN JOURNAL OF ECOLOGY, Issue 1 2010Richard M. Cowling Abstract African elephant and black rhinoceros , both megaherbivores , impact negatively on the abundance of succulent plants, including tree succulents, in South Africa's subtropical thicket. We sampled 35 sites in subtropical thicket to assess historical and contemporary impacts of African elephant and black rhinoceros on the population structure of three species of succulent tree euphorbia. Population age structures were highly variable and showed no species-specific effects. Almost half the sites had growing populations dominated by young individuals. Sites having contemporary impacts had significantly fewer individuals in the 30,75 years age range, but this effect declined with increasing terrain slope. Eighty-one percent of sites assumed to have been impacted by megaherbivores historically had individuals that predated rhino and elephant extirpation in the region. This and other population age structure data indicate that megaherbivores and tree euphorbias coexisted historically on terrain of low relief. However, in areas not subject to contemporary impacts, euphorbia populations are likely to be much higher now than historically, owing to population relaxation after the extirpation of megaherbivores in the mid 1800s. Given the sensitivity of tree euphorbias to megaherbivore impacts, managers should consider monitoring the population structure of these species in order to identify thresholds of potential concern regarding megaherbivore impacts. Résumé L'éléphant et le rhinocéros africains , deux méga-herbivores , ont un impact négatif sur l'abondance de plantes succulentes, y compris des arbres succulents, dans les fourrés subtropicaux d'Afrique du Sud. Nous avons prélevé des échantillons dans 35 fourrés subtropicaux afin d'évaluer les impacts anciens et actuels des éléphants et des rhinos noirs africains sur la structure de la population de trois espèces d'euphorbes arborescentes succulentes. Les structures d'âges des populations étaient très variables et ne présentaient aucun effet spécifique des espèces. Près de la moitié des sites contenaient des populations en croissance dominées par de jeunes individus. Les sites qui présentaient des impacts actuels comptaient significativement moins d'individus de la classe d'âge comprise entre 30 et 75 ans, mais cet effet diminuait lorsque la pente du terrain s'accentuait. Quatre-vingt-un pour cent des sites supposés avoir subi jadis l'impact des méga-herbivores contenaient des individus qui dataient d'avant l'élimination des rhinos et des éléphants. Ceci, tout comme d'autres données sur la structure d'âge des populations, indique que les méga-herbivores et les euphorbes arborescentes ont longtemps coexisté sur les terrains de faible relief. Cependant, dans les zones qui ne subissent aucun impact actuel, les populations d'euphorbes sont susceptibles d'être beaucoup plus hautes aujourd'hui que jadis, en raison de la libération induite par l'élimination des méga-herbivores au milieu des années 1800. Etant donné la sensibilité des euphorbes arborescentes face aux impacts des méga-herbivores, les gestionnaires devraient envisager le suivi continu de la structure de la population de ces espèces afin de déterminer les seuils d'alerte potentiels en ce qui concerne les impacts des méga-herbivores. [source] Early age reproduction in female savanna elephants (Loxodonta africana) after severe poachingAFRICAN JOURNAL OF ECOLOGY, Issue 2 2009M. J. Owens Abstract A 10-year study revealed that after severe poaching (>93% killed) of elephants (Loxodonta africana) in Zambia's North Luangwa National Park (NLNP) during the 1970s and 1980s, the age of reproduction in females was greatly reduced. Fifty-eight per cent of births were delivered by females aged 8.5,14 years, an age at which elephants were reported to be sexually immature in nearby South Luangwa National Park (SLNP) before poaching. The mean age of females at first birth (AFB) (1993, 1994) was 11.3 years. Prior to poaching, the mean age AFB in SLNP was 16 years. The NLNP age structure and sex ratio were skewed, mean family unit size was reduced, and 37% of family units contained no females older than 15 years. Twenty-eight per cent of family units were comprised entirely of a single mother and her calf, and 8% of units consisted only of orphans who would have been considered sexually immature prior to poaching. Only 6% of survivors were older than 20 years, the age at which females in little-poached populations generally become most reproductively active. After a community-based conservation programme and the UN-CITES ban on the ivory trade were introduced, no elephants were recorded killed. In spite of a high reproductive rate, 6 years after poaching decreased, the density of the NLNP population had not increased, supporting predictions that the removal of older matriarchs from family units will have serious consequences on the recovery of this species. Résumé Une étude qui a duré dix ans a révélé qu'après un braconnage très grave (>93% tués) des éléphants (Loxodonta africana) dans le Parc National de Luangwa Nord (NLNP), en Zambie au cours des années 1970 et 1980, l'âge de la reproduction chez les femelles a fort baissé. Cinquante-huit pour cent des naissances se sont passées chez des femelles qui avaient entre 8,5 et 14 ans, un âge auquel les éléphants étaient dits être encore sexuellement immatures dans le Parc National de Luangwa Sud (SLNP), tout proche, avant le braconnage. L'âge moyen des femelles à la première mise-bas (AFB ,at first birth) (1993, 1994) était de 11,3 ans. Avant le braconnage, l'âge moyen à la première mise-bas était de 16 ans au SLNP. Au NLNP, la structure d'âge et le sex-ratio ont été faussés, la taille moyenne de l'unité familiale a été réduite, et 37% des familles ne contiennent aucune femelle de plus de 15 ans. Vingt-huit pour cent des unités familiales n'étaient composées que d'une mère seule et de son jeune, et huit pour cent n'étaient composées que d'orphelins qui devaient être considérés comme sexuellement immatures avant le braconnage. Seuls six pour cent des survivants avaient plus de 20 ans, l'âge auquel les femelles de populations peu braconnées deviennent généralement les plus actives en matière de reproduction. Après l'introduction d'un programme de conservation communautaire et l'interdiction, par la CITES-UN, du commerce de l'ivoire, on n'a plus enregistré aucun massacre d'éléphant. Malgré un taux élevé de reproduction, la densité de population du NLNP n'a pas augmenté, ce qui conforte les prédictions que l'enlèvement des plus vieilles matriarches des unités familiales aura de sérieuses conséquences sur la restauration de cette espèce. [source] Wage differentials between the public and private sectors in India,JOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 3 2007Elena Glinskaya Abstract This study uses 1993,94 and 1999,2000 rounds of India Employment and Unemployment survey to investigate wage differentials between the public and private sectors. To obtain robust estimates of the wage differential, we apply three econometric techniques each relying on a different set of assumptions about the process of job selection and wage formation. All three methods show that differences in wages between public sector workers and workers in the formal-private and informal-casual sectors are positive and high. On average, the public sector premium ranges between 62 and 102 per,cent over the private-formal sector, and between 164 and 259 per,cent over the informal-casual sector, depending on the choice of methodology. The wage differentials in India tend to be higher in rural as compared to urban areas, and are higher among women than among men. The wage differential also tends to be higher for low-skilled workers. There is considerable evidence of an increase in the wage differential between 1993,1994 and 1999,2000. Copyright © 2007 John Wiley & Sons, Ltd. [source] Skills under threat: the case of HIV/AIDS in the mining industry in ZimbabweJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 5 2006Caroline N. Matangi Abstract The Zimbabwe mining industry is currently battling to arrest further spread of the HIV/AIDS crisis in workplaces, especially its impact on labour productivity. Labour in the closed community of mines has been greatly susceptible to HIV/AIDS infection. The current AIDS incidence in the mine sites is estimated at a weighted average of 15,per,cent amongst miners, with the largest category of workers,the 30,39 years age group,also constituting the worst affected category. Given the current state of the country's economy and consequently its adverse impact on the lifestyle of miners, the pandemic is expected to increase. This paper builds on the work of the ILO (1995) involving a survey of 18 various firms/institutions. The survey was carried out in Zambia in order to assess the impact of HIV/AIDS on the productive labour force. The survey revealed that many of the firms are experiencing irregular work attendance, ,wasted' training as some of the trained workers are constantly ill or die, high medical bills, funeral costs and reduced productivity and profits. An analysis of data on the main causes of death in 1993 shows that at least 61.8,per,cent of deaths could be attributed to causes that are very closely related to HIV/AIDS complications. Based on points highlighted by respondents and analysis of symptoms suffered, it was observed that HIV/AIDS tended to affect most general workers (36.8,per,cent), followed by the lower management (30.9,per,cent) and the middle management (20.6,per,cent). Comparatively, 11.8,per,cent of the deaths in 1993 belonged to the top management. Although it is hard to appreciate the meaning of the figures without knowledge of the number of people in each category, it nevertheless helps to form a clear picture of the impact of HIV/AIDS on industry. This paper seeks to further investigate the impact of HIV/AIDS on the productive labour force, by focusing on one particular industry,mining,using a blend of research methods to collect the data. This paper examines the impact of HIV/AIDS on the productive labour force and management responses. It forms part of the findings of data gathered in 2001 in the mining industry in Zimbabwe, to examine factors affecting management responses to HIV/AIDS in the mine sites. Zimbabwe is a country with a complex historical legacy of mine labour. This phenomenon can largely be attributed to the production oriented nature of the mining industry. Mines focus mainly on mineral extraction and as a result the bulk of mine workers tend to be production workers whose skills have developed over long periods of time. Production workers on mines have a tradition of long-term employment. This phenomenon has meant that labour in the mines is hard to replace as a result of skills, especially tacit knowledge, acquired over many years. Thus while the recent closure of some gold mines, largely due to low commodity prices, has meant that more miners are available in the labour market, this situation has not necessarily eased the process of replacing labour lost to the HIV/AIDS epidemic, as certain skills are firm specific. Production workers are predominantly male with the bulk falling in the 35,39 years age group. Most mine workers reside in mine villages, a colonial legacy that ensured miners were close to the workplace. The village system is a system of housing labourers, which demonstrates capitalistic methods of controlling labour and minimising costs. Of significance in this study's background is how the village system has come to be viewed as a factor in the spread of HIV/AIDS in the mining communities, because of its ,closed' nature. It is against this complex historical backdrop that the paper turns to examine the impact of the HIV/AIDS pandemic on production workers and management responses to the crisis using the Resource Based View of the Firm model (RBV), one of the theories in the Strategic Human Resource Management (SHRM) tradition. RBV was chosen for this study out of many HRM models that exist, because this theory, in particular, explains why it is advantageous for sites to use their ,unique' firm based resources in order to achieve sustainable competitive advantage. Given this rationale it was, therefore, presumed that this theory would best apply in mines battling with the adverse impact of HIV/AIDS on productivity, especially in the light of the harsh national economic climate, which would likely place limitations on response mechanisms. Further, the issue of firm-specific skills was also taken into consideration as an important factor in the mines, limiting their ability to resort to external solutions. Thus, given these factors, RBV was deemed the most appropriate model. The study finds that the pandemic depresses labour productivity through a number of significant ways: increased rate of HIV/AIDS induced absenteeism gradual labour turnover as a result of AIDS induced morbidity; and consequently declining skills availability, particularly firm-specific skills. Maintaining labour productivity in the face of gradually diminishing skills and indisposed labour will be key to softening the adverse economic consequences of the pandemic in the mines. To reduce the threat to labour productivity, mines must find ways of utilising, to the maximum extent practicable, existing skills. Results indicate that a move towards the utilisation of existing miners is the most favoured response mechanism in most mines. Utilising existing miners enables mines from spending financial resources on avoidable recruitment and training and quite often mechanisation, which may not necessarily be compatible with the old infrastructure in certain mines. Copyright © 2006 John Wiley & Sons, Ltd. [source] Foreign aid and long-run economic growth: empirical evidence for a panel of developing countriesJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 1 2006Georgios Karras Abstract This paper investigates the relationship between foreign aid and growth in per capita GDP using annual data from the 1960 to 1997 period for a sample of 71 aid-receiving developing economies. The results show that the effect of foreign aid on economic growth is positive, permanent, statistically significant, and sizable: raising foreign aid by $20 per person of the receiving country results in a permanent increase in the growth rate of real GDP per capita by approximately 0.16,per,cent. Using an alternative foreign-aid measure, a permanent increase in aid by 1,per,cent of the receiving economy's GDP permanently raises the per capita growth rate by 0.14 to 0.26,per,cent. Copyright © 2006 John Wiley & Sons, Ltd. [source] Missing persons in the study of groupsJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 1 2005Thomas A. Timmerman This research examined relationships between team-level variables with various patterns of individual non-response. In the first analysis, professional basketball teams (n,=,389) were used to study the relationship between team cooperation and team performance. In the second analysis, the same teams were used to study the relationship between team experience and team performance. In the third analysis, professional baseball teams (n,=,1984) were used to study the relationship between team experience and team performance. Individuals were deleted from the complete data sets to simulate three different types of non-response that might be encountered in organizational group or team research. In all three analyses, team-level relationships were attenuated as individual members were deleted randomly. Team-level relationships were also generally reduced as individuals were deleted as a function of their level of participation with the team. The overall amount of variance explained, however, showed a pronounced curvilinear effect. Namely, in all three analyses, the variance explained in team performance peaked when 30,40,per,cent of the low-participation members were deleted. Finally, in the first analysis, relationships were also attenuated as the least cooperative members were deleted from the data set. The results demonstrate the need for researchers to understand the diverse effects of various types of non-response in team and group research. Copyright © 2005 John Wiley & Sons, Ltd. [source] On the Cost of Adverse Selection in Individual Annuity Markets: Evidence From SingaporeJOURNAL OF RISK AND INSURANCE, Issue 2 2002Wai Mun Fong New evidence is presented on the cost of adverse selection in individual annuity markets using Singapore data. The Singapore annuity market is an interesting setting to examine the cost of adverse selection for three reasons. First, unlike many Western countries, the Singapore government provides very limited public financial assistance for retirees. Second, while social security contributions mandated under the Central Provident Fund (CPF) result in a high forced savings rate, a large proportion of CPF savings, are used up for housing. Third, to ensure that retirees have sufficient funds to meet basic needs, individuals who reach age 55 are required to set aside a minimum amount of their CPF savings, which can be withdrawn at age 62. The CPF Board allows various options for investing the minimum sum, but the most attractive option is to purchase an annuity. The institutional setting in Singapore in effect provides insurers with a large captive market for annuities. It is conjectured that this should be reflected in a significantly lower cost of adverse selection for annuities sold in Singapore as compared with other countries. The results herein, using data for CPF-approved insurers, are strongly consistent with this conjecture. On average, money's worth of annuities is higher than annuities sold to a similar age-gender mix in the United States, United Kingdom, and Australia. Adverse selection accounts for less than 13 percent of the cost of longevity insurance compared to 30,50 per- cent documented in many previous studies. These results suggest that one way to resolve the adverse selection problem is to adopt a universal individual defined contribution pension scheme that mandates or provides strong incentives for retirees to purchase annuities. [source] Fodder production and soil health with conjunctive use of saline and good quality water in ustipsamments of a semi-arid regionLAND DEGRADATION AND DEVELOPMENT, Issue 2 2007R. K. Yadav Abstract Food and fodder shortage in arid and semi-arid regions force farmers to use marginal quality water for meeting the water requirement of crops which result in low quality, reduced production and an adverse impact on soil properties. A field study on loamy-sand (Hyperthermic Typic Ustipsamments) saline soil was conducted during 1999,2001 at Central Institute for Research on Buffaloes, Hisar. This involved assessment of effects of conjunctive use of saline water, EC,=,4·6,7·4,dSm,1, SAR,=,14,22 ((mmol,1)½ with good quality water on five fodder crop rotations: oat-sorghum (Avena sativa- ,Sorghum bicolor), rye grass,sorghum (Loleum rigidum,Sorghum bicolor), Egyptian clover,sorghum (Trifoleum alexandrinum,Sorghum bicolor), Persian clover,sorghum (Trifoleum resupinatum,Sorghum bicolor) and Indian clover,sorghum (Melilotus indica,Sorghum bicolor) and certain soil properties associated with it. Leguminous winter fodder crops were more sensitive to poor quality water use. Reductions in fodder yield with use of saline water alone throughout season were 85, 68, 54, 42, 36 and 26 per,cent in Indian clover, Egyptian clover, Persian clover, oat, rye grass and sorghum respectively as compared to good quality water. Leguminous fodder crops produced protein rich (12,14 per,cent) and low fibre (18,20 per,cent) fodder as compared to poor quality grassy fodder under good quality water irrigation but their quality deteriorated when saline water was used. These leguminous crops accumulated proportionately higher Na+ (1·58 per,cent) resulting in adverse impact on their growth as compared to grassy fodder crops. Higher soil salinity (12·2,dSm,1), SAR,=,20 (mmol,1)½ was recorded with saline water irrigation; and slight adverse impact was noticed on infiltration rate and contents of water dispersible clay. Alternate cyclic use of canal and saline water could be an option for fodder production under such conditions. Copyright © 2006 John Wiley & Sons, Ltd. [source] Land use and soil erosion in the upper reaches of the Yangtze River: some socio-economic considerations on China's Grain-for-Green ProgrammeLAND DEGRADATION AND DEVELOPMENT, Issue 6 2006H. L. Long Abstract Soil erosion in the upper reaches of the Yangtze River in China is a major concern and the Central Government has initiated the Grain-for-Green Programme to convert farmland to forests and grassland to improve the environment. This paper analyses the relationship between land use and soil erosion in Zhongjiang, a typical agricultural county of Sichuan Province located in areas with severe soil erosion in the upper reaches of the Yangtze River. In our analysis, we use the ArcGIS spatial analysis module with detailed land-use data as well as data on slope conditions and soil erosion. Our research shows that the most serious soil erosion is occurring on agricultural land with a slope of 10,25 degrees. Both farmland and permanent crops are affected by soil erosion, with almost the same percentage of soil erosion for corresponding slope conditions. Farmland with soil erosion accounts for 86·2,per,cent of the total eroded agricultural land. In the farmland with soil erosion, 22·5,per,cent have a slope of,<,5 degrees, 20·3,per,cent have a slope of 5,10 degrees, and 57·1,per,cent have a slope of,>,10 degrees. On gentle slopes with less than 5 degrees inclination, some 6,per,cent of the farmland had strong (5000,8000,t,km,2,y,1) or very strong (8000,15000,t,km,2,y,1) erosion. However, on steep slopes of more than 25 degrees, strong or very strong erosion was reported for more than 42,per,cent of the farmland. These numbers explain why the task of soil and water conservation should be focused on the prevention of soil erosion on farmland with steep or very steep slopes. A Feasibility Index is developed and integrated socio-economic assessment on the feasibility of improving sloping farmland in 56 townships and towns is carried out. Finally, to ensure the success of the Grain-for-Green Programme, countermeasures to improve sloping farmland and control soil erosion are proposed according to the values of the Feasibility Index in the townships and towns. These include: (1) to terrace sloping farmland on a large scale and to convert farmland with a slope of over 25 degrees to forests or grassland; (2) to develop ecological agriculture combined with improving the sloping farmland and constructing prime farmland and to pay more attention to improving the technology for irrigation and cultivation techniques; and (3) to carry out soil conservation on steep-sloping farmland using suggested techniques. In addition, improving ecosystems and the inhabited environment through yard and garden construction for households is also an effective way to prevent soil erosion. Copyright © 2006 John Wiley & Sons, Ltd. [source] Subsurface drainage for reversing degradation of waterlogged saline landsLAND DEGRADATION AND DEVELOPMENT, Issue 6 2006D. P. Sharma Abstract In irrigated agriculture of arid and semiarid regions waterlogging coupled with salinity is a serious problem. Experimental evidence at several locations has led to the realization that subsurface drainage is an essential intervention to reverse the processes of land degradation responsible for the formation of waterlogged saline lands. This paper presents the results of a study conducted from 1995 to 2000 to evaluate the impacts of subsurface drainage on soil properties, groundwater-table behaviour and crop productivity in a waterlogged saline area of 2200,ha. A subsurface drainage system was installed at 1·6,m depth with 60,m drain spacing covering an area of 1200,ha (23 blocks) during 1997,99 and compared with an undrained block of 1000,ha. Subsurface drainage facilitated the reclamation of waterlogged saline lands and a decrease in the soil salinity (ECe, dS,m,1) that ranged from 16·0 to 66·3,per,cent in different blocks. On average, 35·7,per,cent decrease in salt content was observed when compared with the initial value. Provision of subsurface drainage controlled the water-table below the root zone during the monsoon season and helped in bringing the soil to optimum moisture content for the sowing of winter crops. In the drained area, the increase in yields of different crops ranged from 18·8 to 27·6,per,cent. However, in the undrained area the yield of different crops decreased due to the increased waterlogging and soil salinity problems. Overall the results indicated that investment in subsurface drainage is a viable option for reversing the land degradation of waterlogged saline lands in a monsoon climate. Copyright © 2006 John Wiley & Sons, Ltd. [source] Reducing runoff by managing crop location at the catchment level, considering agronomic constraints at farm levelLAND DEGRADATION AND DEVELOPMENT, Issue 5 2006A. Joannon Abstract Runoff and erosion cause frequent damage through muddy floods in the loess belt of Northern Europe. One possibility for reducing damage is to lower runoff on agricultural land by spatially alternating different crops at the catchment level. But crop location results from decisions taken at the farm level. This study aimed to assess the existing leeway to modify crop location in the farms of a catchment, in order to reduce runoff at the catchment's outlet. The case study was the Bourville catchment (1086,ha), cultivated by 28 farmers and located in Pays de Caux, France. First, crop location rules in the 14 main farms of the catchment were analysed on the basis of surveys carried out with farmers, distinguishing spatial constraints from temporal ones. These rules made it possible to simulate crop location on each farm territory for the 2001,2002 crop year. Each field of the catchment was classified depending on whether one or several crops could be sown, taking into account both field history and farmer decision rules. Then two extreme scenarios of crop location in the Bourville catchment were built. Runoff simulation at the outlet with the STREAM model showed that runoff could be reduced while sticking to current farmer decision rules in terms of crop location. Depending on rainfall event characteristics, runoff reduction varied between 13·5,per,cent and 4·5,per,cent. Copyright © 2006 John Wiley & Sons, Ltd. [source] How project approach influences adoption of SWC by farmers, examples from southern MaliLAND DEGRADATION AND DEVELOPMENT, Issue 5 2006F. Bodnár Abstract Choices in project approach affect the continuation of soil and water conservation (SWC) after project withdrawal, and thus the sustainability and cost effectiveness of the project. A SWC project was carried out in southern Mali between 1986 and 1998. Its features were the promotion of cheap and simple SWC measures, a participatory village extension approach with limited use of incentives, and the incorporation of the SWC programme in an existing Malian extension service. By 2000, farmers in half the 5000 villages in southern Mali had been trained in SWC. By 2002, erosion-control measures had been installed in 94,per,cent of the villages in southern Mali by 46,per,cent of the farmers and in 15,per,cent of the fields. Though external donor support has stopped, farmer adoption is steadily continuing and spreading to untargeted villages. Copyright © 2006 John Wiley & Sons, Ltd. [source] The impact of changing olive cultivation practices on the ground flora of olive groves in the Messara and Psiloritis regions, Crete, GreeceLAND DEGRADATION AND DEVELOPMENT, Issue 3 2006H. D. Allen Abstract This paper examines the impact that different olive cultivation practices have on the nature of the ground flora of olive groves in the region of the Psiloritis massif and Messara Plain in central and southern Crete, Greece. In lower, flatter areas there are areas of both traditional and intensive forms of olive cultivation. In more marginal, upland areas there are traditional terraced olive groves, some of which are being abandoned. The relationship between the vegetation composition of the ground flora and environmental variables was established, by means of TWINSPAN® and ordination analysis, using survey data from nineteen sites across the region. Four vegetation communities are identified: olive with herbaceous taxa; olive with sclerophyllous shrub taxa; and two forms of sclerophyllous shrub communities. Ordination results indicate that environmental variables, such as soil characteristics, slope aspect and slope angle, explain about 60,per,cent of the species,environment relationships. The remaining variation in species composition is interpreted to be the result of different cultivation practices. The implications for land degradation are examined, in particular the changes in vegetation diversity of both intensive and semi-abandoned olive groves, the potential for increased soil erosion, and the risk of fire as a result of increased fuel loading as flammable shrubs invade abandoned terraces. Intensification of olive cultivation in Crete, and across the Mediterranean, has been encouraged by subsidies from the European Union leading to rapid landscape change. Thus there is a need to monitor changes in olive cultivation practices both at the local scale, by means of ground-based fieldwork, and at landscape and regional scales, by means of remote sensing. Copyright © 2006 John Wiley & Sons, Ltd. [source] Costing yield loss from acidity, sodicity and dryland salinity to Australian agricultureLAND DEGRADATION AND DEVELOPMENT, Issue 5 2005S. Hajkowicz Abstract Salinity, sodicity and acidity are three major soil constraints that limit crop and pasture yields in Australia. In this paper estimates are made of the potential benefits arising from their treatment by measuring and mapping their impact on agricultural profit. This is achieved by estimating the increase in profit for Australia's main commodities that would occur if the three soil constraints were costlessly ameliorated. These estimates reveal the upper achievable limit on investment returns. They are also indicative of each soil constraint's economic significance to Australian agriculture. It was found that costless removal of salinity would increase annual profits by A$187 million, sodicity by A$1034·6 million and acidity by A$1584·5 million. This equates to 2·9,per,cent, 15·8,per,cent and 24·2,per,cent of total net economic return. It was also found that worsening salinity extent and severity over 2000,2020 has a present value of A$496,A$712 million. Although soil salinity is currently the focus of much public attention, this analysis suggests that from a production viewpoint the correction of sodic and acidic soils may create greater private economic benefit. Opportunities vary considerably among industries. In particular, there is considerable opportunity for the horticultural and viticultural sector to address acidity issues. Whether gross benefits translate into net benefits is a complex question requiring access to context and location-specific information. Copyright © 2005 John Wiley & Sons, Ltd. [source] Farmers' perceptions of soil erosion and its consequences in India's semiarid tropicsLAND DEGRADATION AND DEVELOPMENT, Issue 3 2005J. Kerr Abstract This paper investigates farmers' perceptions of soil erosion and how it affects crop yields, land values, and private conservation investments in India's semiarid tropics. It is based on three types of data: (1) a survey of farmers in three study villages; (2) a plot survey by a professional soil surveyor in the same villages; and (3) experimental and simulated data from nearby research stations with similar conditions. Farmers' perceptions of erosion are compared to the surveyor's using kappa, a statistical measure of interrater agreement. Perceived erosion,yield relationships are estimated econometrically and compared to experimental and simulated data. Effects on land values and conservation investments are estimated econometrically. Findings suggest that farmers are keenly aware of rill erosion but less aware of sheet erosion; kappa values ranging from 0 to 0·28 suggest low agreement with the soil surveyor. They anticipate annual yield losses of 5·8,11,per,cent due to rill erosion; these figures are reasonably consistent with those from nearby research stations. They anticipate yield increases of 3·8,14·5,per,cent due to installation of soil conservation bunds, largely because they can harvest soil from up the slope and capture organic matter. Perceived erosion has some effect on land values and soil conservation investments, but other factors such as irrigation and soil type have a much greater effect. These findings suggest that promoting soil conservation requires capitalizing on farmers' interest in short-term gains, such as from water and nutrient management. Copyright © 2005 John Wiley & Sons, Ltd. [source] Limiting factors for reforestation of mine spoils from Galicia (Spain)LAND DEGRADATION AND DEVELOPMENT, Issue 1 2005F. A. Vega Abstract Mined areas are a continuing source of heavy metals and acidity that move off site in response to erosion. Revegetation of the mine tailings could limit the spread of these heavy metals and acidity. This study was conducted to evaluate, at four tailings on opencast mines of Galicia (Touro: copper mine; and Meirama: lignite mine, NW Spain), the chemical and physical soil quality indicators and limiting edaphic factors concerning forest production. Selected zones were: (1) The tailings formed by the waste materials from the depleted Touro mine; (2) the decantation site of deposited sludge coming from the copper extraction in the flotation stage; (3) and (4) tailings of 3 and 10 years old of the Meirama lignite mine. The main physical limitations of the mine soils are the low effective depth (<50,cm), high stoniness (>30,per,cent) and high porosity (>60,per,cent); which make them vulnerable to soil erosion and seriously interferes with the forest production. Soils coming from the decantation site of copper mine do not have physical limitations. The main chemical limitations of mine soils are their acidity (pH from 3·62 to 5·71), and aluminium saturation (>60,per,cent in copper mine soils, and >20,per,cent in lignite mine soils), low CECe (from 5·34 to 9·47,cmol(+),kg,1), organic carbon (from 0·47 to 7·52,mg,kg,1) and Ca2+ and Mg2+ contents, and imbalance between exchange bases. Mine soils coming from the decantation site of copper mine soils are strongly limited by the high Cu content (1218,mg,kg,1). Lime and organic amendments are the most important factors in providing a suitable medium for plant growth. Copyright © 2004 John Wiley & Sons, Ltd. [source] Throughfall, runoff and soil erosion after prescribed burning in gorse shrubland in Galicia (NW Spain)LAND DEGRADATION AND DEVELOPMENT, Issue 1 2005J. A. Vega Abstract The first-year effect of two different prescribed burning treatments on throughfall, runoff and soil erosion was evaluated in gorse shrubland (Ulex europaeus L.) in Galicia (NW Spain). The treatments compared were: intense burn, light burn and control (no burn). Accumulated annual throughfall represented between the 81 and 87,per,cent of total rainfall in intensely burned and lightly burned areas, respectively, whereas in the unburnt areas it was 60,per,cent. No significant differences between burning treatments were found for the annual throughfall. However, runoff was significantly greater in intensely burned plots (1·5-times) than in lightly burned plots. Burning also resulted in a significant increase in runoff (between 2·5 and 1·7-times, respectively) compared with controls. Total soil losses were small in all treatments, but the intense burn caused significantly greater soil erosion (5·8-times) compared with the unburned areas. Soil losses after the light burn did not significantly differ from the control although they were higher (2·3-times). The relationships obtained between erosion and several rainfall parameters were significantly different in burned areas compared to the control. The same response was observed for runoff. Annual erosion losses showed a strong dependence on percentage of bare soil even for small values of this variable. Litter thickness was also a very important variable influencing on erosion rates. This study indicated that by combining ignition techniques and high litter moisture content to maintain the percentage of bare soil below 85,per,cent, soil erosion was low. Nevertheless, this result was constrained by the low rainfall that occurred during the study. Copyright © 2005 John Wiley & Sons, Ltd. [source] The economics of soil productivity: local, national and global perspectivesLAND DEGRADATION AND DEVELOPMENT, Issue 6 2004D. J. Knowler Abstract Soil degradation is a mounting problem on many smallholder lands in developing countries. Economic analysis has been an important tool in addressing this problem, beginning with assessments of the financial attractiveness of investing in soil conservation works. Data compiled from 67 studies of the financial attractiveness of conservation technologies suggest that many can provide positive net returns at the farm level (64·2,per,cent). While such studies have made a valuable contribution, economists have been exploring additional applications of economics to the problem, such as the development of new perspectives under the guise of ecological economics. As a result, this paper argues it is an opportune time to assess progress in the field of economic analysis of soil degradation and to consider the policy ramifications of this research. Key issues are grouped into farm-level considerations, national policy linkages and global issues. A number of policy implications emerge. Clearly, devising effective incentives at the farm or community (collective action) level must be a priority. As part of this effort, even more attention should be paid to the influence of macroeconomic and sectoral policies on soil productivity. Since soil degradation is also a problem with global ramifications, there is a clear rationale for intervention at the international level via mechanisms such as international transfers. Copyright © 2004 John Wiley & Sons, Ltd. [source] Carbon sequestration in soils of central Asia,LAND DEGRADATION AND DEVELOPMENT, Issue 6 2004R. Lal Abstract Problems of frequent drought stress, low soil organic carbon (SOC) concentration, low aggregation, susceptibility to compaction, salinization and accelerated soil erosion in dry regions are accentuated by removal of crop residues, mechanical methods of seedbed preparation, summer clean fallowing and overgrazing, and excessive irrigation. The attendant soil degradation and desertification lead to depletion of SOC, decline in biomass production, eutrophication/pollution of waters and emission of greenhouse gases. Adoption of conservation agriculture, based on the use of crop residue mulch and no till farming, can conserve water, reduce soil erosion, improve soil structure, enhance SOC concentration, and reduce the rate of enrichment of atmospheric CO2. The rate of SOC sequestration with conversion to conservation agriculture, elimination of summer fallowing and growing forages/cover crops may be 100 to 200,kg,ha,1,y,1 in coarse-textured soils of semiarid regions and 150 to 300,kg,ha,1,y,1 in heavy-textured soils of the subhumid regions. The potential of soil C sequestration in central Asia is 10 to 22,Tg,C,y,1 (16±8,Tg,C,y,1) for about 50 years, and it represents 20,per,cent of the CO2 emissions by fossil fuel combustion. Copyright © 2004 John Wiley & Sons, Ltd. [source] Semiarid land rehabilitation by direct drilling in the South Island, New Zealand,plant species and establishment technologyLAND DEGRADATION AND DEVELOPMENT, Issue 5 2004B. J. Wills Abstract Large areas of the east coast and inland basins of the South Island, New Zealand, are affected by periodic drought and/or semiarid climatic conditions, particularly during cyclic El Niño climatic events. The severity of these environmental conditions places great stress on introduced and native pasture species and frequently results in poor establishment of new pastures using standard drilling techniques. The objective of this study was to determine effective, practical means of rehabilitating semiarid land (about 470,mm annual rainfall) on a site in Central Otago. A comparison of two direct drilling methods, a novel strip-seeder drill and a standard hoe-coulter drill, was conducted in a trial initiated during spring 1998. Five drought-tolerant forage species were established: wheatgrass (Thinopyron intermedium), tall oat grass (Arrhenatherum elatius), birdsfoot trefoil (Lotus corniculatus), hairy dorycnium (Dorycnium hirsutum) and bluebush (Kochia prostrata). For the 2000/2001 growing season, species established with the strip-seeder drill had an overall mean herbage biomass of 235,g,m,,2,, three-times that for the hoe-coulter drill (77,g,m,,2,, P,<,0·001). Differences in herbage biomass between species were observed, with hairy dorycnium (mean 328,g,m,,2,) producing significantly (P,<,0·001) more herbage biomass than the other species. After the third spring, the percentage ground cover recorded from transects across the strip-seeder drill plots (cf. the hoe-coulter drill) was: wheatgrass,41,per,cent (10,per,cent); tall oat grass,44,per,cent (25,per,cent); birdsfoot trefoil,25,per,cent (5,per,cent); hairy dorycnium,50,per,cent (19,per,cent); and bluebush,4,per,cent (0,per,cent). The native plant content of the resident vegetation was reduced as a result of the drilling treatments and also when fertilizer was added to undistrubed pasture. The strip-seeder drill is capable of providing superior plant growth on dryland sites even during adverse drought conditions. It produces a furrow approximately 16,cm wider than the hoe-coulter drill, exerts a greater shattering effect on the soil structure and places fertilizer at depth. It is suggested that this assists plant establishment by providing good seedling protection from wind and sun, and subsequent plant growth by allowing easier root penetration to the subsoil where nutrients and moisture are available. Copyright © 2004 John Wiley & Sons, Ltd. [source] Wheat field erosion rates and channel bottom sediment sources in an intensively cropped northeastern Oregon drainage basin,LAND DEGRADATION AND DEVELOPMENT, Issue 1 2004G. N. Nagle Abstract Sediment tracers were used to quantify erosion from cultivated fields and identify major source areas of channel bottom sediment within the Wildhorse Creek drainage, an intensively cropped tributary of the Umatilla River in northeastern Oregon, USA. Available data indicated that Wildhorse Creek was one of the largest sediment yielding tributaries of the Umatilla River. Carbon, nitrogen and the nuclear bomb-derived radionuclide 137Cs were used as tracers to fingerprint sediment sources. Sediment was collected from the stream bottom and active floodplain and compared to samples from cultivated fields and channel banks. Samples were characterized on the basis of tracer concentrations and a simple mixing model was used to estimate the relative portion of bottom sediment derived from cultivated surface and channel banks. The results indicate that the amount of bottom sediment derived from cultivated surface sources was less than 26,per,cent for the 1998 winter season, although this estimate has a high margin of error. Cesium-137 was also used to estimate surface erosion from three cultivated fields in the watershed. Annual estimates of erosion since 1963 from the three sampled fields were from 3 to 7,5,t,ha,1 yr,1. For the 1998 season, it appears that most channel-bottom sediment was of subsurface origin with much of it likely coming from channel and gully banks indicating that significant reductions in sediment in Wildhorse Creek might be accomplished by the stabilization of eroding riparian areas and swales on the lower slopes of agricultural fields. Published in 2004 by John Wiley & Sons, Ltd. [source] Runoff and losses by erosion in soils amended with sewage sludgeLAND DEGRADATION AND DEVELOPMENT, Issue 6 2003G. Ojeda Abstract In order to promote the transformation of a burnt Mediterranean forest area into a dehesa system, 10,t,ha,1 of dry matter of the same sewage sludge in three different forms: fresh, composted and thermally-dried, were added superficially to field plots of loam and sandy soils located on a 16,per,cent slope. This application is equivalent to 13,8,t,ha,1 of composted sludge, 50,t,ha,1 of fresh sludge and 11,3,t,ha,1 of thermally-dried sludge. The surface addition of a single application of thermally-dried sludge resulted in a decrease in runoff and erosion in both kinds of soil. Runoff in thermally-dried sludge plots was lower than in the control treatment (32,per,cent for the loam soil and 26,per,cent for the sandy soil). The addition of any type of sludge to both soil types also reduces sediment production. Significant differences between the control and sludge treatments indicate that the rapid development of plant cover and the direct protective effect of sludge on the soil are the main agents that influence soil erosion rates. Results suggest that the surface application of thermally-dried sludge is the most efficient way to enhance soil infiltration. Copyright © 2003 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||