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211.
Managing crop damage by wildlife is a complex challenge in agrarian-wildlife landscapes. Losses to farmers and their negative attitude towards crop-raiding wildlife, compromise wildlife conservation and farmer-wildlife coexistence. Priority crop types, crop-raiding wildlife and socio-ecological factors are highly integrated. Here we use cross-sectional network analysis as a conservation planning tool to simultaneously identify the crop types used by crop-raiding wildlife, and evaluate the importance of these crop-wildlife interactions relative to the socio-ecological factors that affect these interactions. The most vulnerable crops were maize, millet and fruit trees, while the most problematic crop-raiding wildlife were African elephant, bushpig, hippo, warthog and red-billed quelea. Crop damage declined with countermeasure effectiveness, farm size, and distance from river to farm, but increased with richness of attractive crops. Undamaged crops included cash crops, such as chili, onion, ginger, lemon grass and garlic. Applying network analysis to different crops and damage scenarios enables identification of the most important and influential crops, crop-raiding wildlife and socio-ecological factors needed to develop effective crop protection strategies. 相似文献
212.
Hans Visser Murillo De Oliveira Villela Filho Andreas Liese Carel A. G. M. Weijers Jan C. Verdoes 《Biocatalysis and Biotransformation》2013,31(1):33-40
The Rhodotorula glutinis epoxide hydrolase, Eph1, was produced in the heterologous host Escherichia coli BL21(DE3) in order to develop a highly effective epoxide hydrolysis system. A 138-fold increase in Eph1 activity was found in cell extracts of the recombinant E. coli when compared to cell extracts of Rhodotorula glutinis, despite the formation of Eph1 inclusion bodies. Optimization of cultivation conditions and co-expression of molecular chaperones resulted in a further increase in activity and a reduction of the inclusion bodies formation, respectively. Compared to Rhodotorula glutinis cells and cell extracts, a total increase in Eph1 activity of over 200 times was found for both Escherichia coli cells and crude enzyme preparations of these cells. The improved conditions for recombinant Eph1 production were used to demonstrate the Eph1-catalysed kinetic resolution of a new Eph1 substrate, 1-oxaspiro[2.5]octane-2-carbonitrile. 相似文献
213.
With the acceleration of China's urbanization and economic development, the ecological conditions of some areas have deteriorated, which has seriously affected the balance of ecological sustainability and socio-economic development. Therefore, how to formulate scientific partitioning strategies for both regional socio-economic development and ecological protection has become a key issue. Aimed at maintaining and improving regional sustainability, we established a partitioning indicator system of China considering 19 value indicators. We constructed the separate sets of the ecological values and economic-development values layers. Based on these two categories, China is classified into four types of functional areas, which are defined as key protected area, development area, low-tension area and conflict area. Finally, the Zonation model was used to identify the important regions of ecological sublayers, then these regions were overlapped with the conflict area to identify the key regions in conflict status which need more attention for ecological sustainability. The main research results are as follows: The ecological situation is generally better in southern China, while the development degree is higher in eastern China. The partitioning map shows that key protected areas mainly distributed in the Qinghai-Tibet Plateau and parts of northeast China, and the existing nature reserves can protect most of the high-value regions of protected areas. In addition, most of the land in southeast China is identified as conflict areas. Though only 12% of high-quality habitats identified by Zonation are located in conflict areas, but nearly one-third of these habitats are in extreme-conflict status. The research results can provide a scientific basis for decision-making agencies to optimize regional ecological value and socio-economic benefits for regional sustainability. 相似文献
214.
Abstract. Grid maps are used as a basic vegetation data base in Japan; they are simplified from vector-based vegetation maps. We estimated the frequency error or lack of information corresponding to reduced resolution and examined the reliable limits of this data base. We produced 10 grid maps on five different scales from 50 m to 1000 m using two different methods using both the whole cell (W-method) and only the central circle (C-method) from a vegetation map at scale 1: 25 000. We found that patches larger than the area of a cell on a vector-based map could be kept almost certainly on any map, but many patches of less than the cell size were lost. The number of missing patches with the C-method is fewer at every scale than those with the W-method. Though the value of Morisita's Cλ (p) index showed that the similarity with the original map was high - from the 50-m to the 200-m resolution - it was increasingly lower on the 400-m and 1000-m grid maps. The values of the Shannon index on the original map, 50-m and 100-m grid maps were not different, but they decreased from the 200-m to 1000-m grid maps. Because the vegetation data base of the Japanese Environment Agency used a 1000-m C-method grid map, we found that much information on patches less than 100 ha had disappeared. Information about dominant vegetation or large patches is almost accurate in this data base. 相似文献
215.
Joan B. Silk 《Primates; journal of primatology》1997,38(3):265-279
Reconciliation has been the subject of considerable research in the last decade, and researchers have demonstrated that in
many species of Old World monkeys and apes former opponents are more likely to engage in friendly interactions in the minutes
that follow conflicts than they are at other times.de Waal has suggested that the function of these interactions is to mend relationships that have been damaged by conflict. Although
peaceful post-conflict interactions are thought to have long-term effects upon the nature of social relationships, behavioral
evidence presently indicates that the effects of these interactions may be limited to the post-conflict period. Theoretical
considerations also raise some doubts about whether the relationship-repair hypothesis is cogent. Data that demonstrate that
peaceful post-conflict interactions facilitate peaceful interactions and relieve victim's uncertainty and anxiety about whether
conflict will be continued suggest that peaceful post-conflict interactions may be a means to reestablish contact with former
opponents. Thus, they appear to function as predictive signals that the actor is going to stop fighting and behave peacefully.
Such signals may be important in a broad range of social contexts. 相似文献