Agrarian change and land-use strategies among Iraqw farmers in northern Tanzania

This paper explores the variety of factors which influence Iraqw fanners' land-use strategies in northern Tanzania. Based on archival research, oral history, and detailed field research, this study illustrates the ways in which access to and availability of resources through social networks and markets over time are critical to farmers' decisions about how to use their labor and land. This detailed local study of agrarian change examines how wider, regional processes of change affect local conditions. It demonstrates that population growth neither results automatically in intensification nor in degradation of the resource base. The paper also attempts to explore how ideas about farming and progress shape farmers' decisions about land use.     

生态系统工程与现代混农林业生产体系

当今世界面临着人口剧增,能源短缺和环境恶化等危机。在第三世界人口飞速增长,耕地需求扩大,毁林种粮,弃林从牧的问题十分严重,引起土壤肥力衰退,水土流失,气候失调,环境恶化,从而阻碍了农牧业的发展。为了保护森林,维护环境,解决农林、牧林业之间的矛盾,有效的途径就是将农、林、牧业有机地结合起来,建立林-农复合生态系统。因而发展农林业在国际上受到充分重视,早于1977年就成立了国际农林业研究中心(ICRAF),推动农林业的研究与生产。我国对农林业的研究与推广近年来也有长足的发展。预计农林业将成为现代农业和林业的发展趋势之一。为此,我们请南京林业大学熊文愈教授和姜志林教授负责组稿、审稿和修改论文,共汇集农林业的论文16篇。这些论文部分反映了当前我国农林业的理论研究工作和实际生产经验。现经本刊编辑,计划作为农林业专题在本刊分四期刊出,以引起广大读者对农林业的重视。在此我们对熊文愈和姜志林二位教授的积极支持表示衷心的感谢。     

热带林下的砂仁栽培

阳春砂仁(Amomum villosumL。)是中国的传统药用植物,它的种子团称为砂仁,果皮称为砂壳,皆可入药,有温脾、健胃、消食、行气之功效,主治胃炎、积食不消等,是30多种中成药的主要成分,还可用作调味佐料等,具有很高的经济价值。阳春砂仁原产广东省阳     

Canopy tree preference by insectivorous birds in shade‐coffee farms: Implications for migratory bird conservation

Land converted to coffee agriculture occupies >5 million hectares of what was once prime overwintering natural habitat in the American Neotropics for migrating birds. When tree canopy is retained or restored (i.e., shade‐grown), coffee farms can serve as habitat refuge for wildlife. Yet few studies have examined whether canopy tree identity impacts habitat quality for biodiversity. Specifically, whether or not certain tree species are disproportionately important for foraging insectivorous birds remains unclear. In this study, we quantified bird foraging activity on 22 tree species in two Latin American Bird Friendly© coffee farms. Specifically, we conducted timed observations on focal trees to determine 1) tree preferences, 2) foraging bird abundance, 3) foraging time, and 4) species richness of birds using each canopy tree species. We found that birds did not forage randomly, and instead exhibited preferences for particular native tree species. Nitrogen‐fixing Fabaceae were consistently used more frequently, supported more resident and migratory birds for longer periods of time, and supported more bird species than trees in other families. We posit that the potential mechanism contributing to tree preferences is the increase in insect abundance and diversity that provide high‐quality food for insectivores but do not present pest problems for coffee. Thus, tree species that support insects may provide multiple benefits for farmers in the form of bottom‐up soil fertilization and top‐down pest control. This study provides evidence that agroforestry land can be improved for birds of conservation concern by prioritizing canopy tree species that help birds and farm productivity.     

La signification de l’Aurignacien du Zagros

The concentration of Aurignacian sites in the Zagros mountain range (Iran, Iraq) implies two important consequences in the ancient history of the Eurasian continent. On the one hand, this core area will spread (through the Near East, Anatolia, the Caucasus and the Crimea) the lifeways and the modern population. On the other hand, this geographical situation corresponds to the southern area of the great Asian plain, extended from the Altai Mountains and centred on Bactria. In this immense and game-filled area, constant innovations appear both in the behavioural and anatomical domains. The Zagros is thus both the frontier and the reservoir of modern humanity, stemming from central Asian experiences, those that will spread widely and then take the place of the European Middle Palaeolithic.     

Modes of Communication and Effectiveness of Agroforestry Extension in Eastern India

Development of extension in agroforestry draws on the application of the innovation-diffusion process in agriculture. To be effective, agroforestry extension needs to fit the dynamics of the target farming system, the local socioeconomic and technological systems, and land use constraints. Failure of agroforestry extension has been blamed on inadequate and inappropriate methods, but there have been few studies to identify those factors that determine a farmer's awareness of, or attitude to, agroforestry. The present study focused on the modes of communication used in extension and how they affected adoption of agroforestry in a subsistence farming region of eastern India. The decision to adopt agroforestry was found to be determined by the farmers' attitude to agroforestry, which in turn was shaped by information received through farmer-to-farmer and farmer-to-extension contact. The mode of communication was important and, to be effective, needs to be customized for each target group.     

A three-dimensional analysis of tooth-root morphology in living bears and implications for feeding behaviour in the extinct cave bear

ABSTRACT

The morphology of both crowns and tooth-roots reflects dietary specialisation in mammalian carnivores. In this article, we analyse the tooth-root morphology of maxillary teeth from CT scans of living bears (Ursus arctos, Ursus americanus, Ursus maritimus, Ursus thibetanus, Melursus ursinus, Helarctos malayanus, Tremarctos ornatus and Ailuropoda melanoleuca) in order to make inferences about the diet and feeding behaviour of the extinct cave bear (Ursus spelaeus sensu lato). Specifically, we investigate two major mitochondrial clades of extinct cave bears recognized by previous authors: Ursus ingressus and Ursus spelaeus (U. spelaeus spelaeus, U. spelaeus ladinicus, U. spelaeus eremus). Our results indicate a close association between tooth-root surface area and feeding behaviour in all living bear species. Tooth-root surface area values of cave bears suggest that they relied more on vegetative matter than living brown bears (Ursus arctos) but subtle differences between these species/subspecies could also indicate different feeding strategies among the members of cave bear complex.     

《生物信息学》本科教学初探

针对生物信息学本科教学中的教学方法、实验教学、考核办法以及如何与现代教育技术相结合进行了初步的探索,并对如何提高教学效果培养跨学科的生物信息学人才做了深入思考。