Farmers’ perspectives on climate change manifestations in smallholder cocoa farms and shifts in cropping systems in the forest-savannah transitional zone of Ghana

The study was conducted to explore actual manifestations of climate change in smallholder cocoa farms to aid extension response to climate impacts, and to understand the reasons for a renewed interest in cocoa production in the forest-savanna agro ecological landscape in Ghana, in spite of unfavorable climatic conditions. Two hundred cocoa farmers were interviewed in nine cocoa farming communities. Selected farms were also visited to document on-farm manifestation of climate impacts as well as innovations and strategies farmers are employing to respond to the adverse impacts of climate change on their cocoa systems. The results revealed various manifestations of climate impacts on cocoa farms which included, increased incidence of pests and diseases, wilting of cocoa leaves, high mortality of cocoa seedlings which affected expansion and farm rehabilitation, and wilting of cherelles resulting in low yield. The farmers maintained that their response to the immediate impacts of climate on cocoa was a shift to cereals due to the unpredictable climatic patterns and the shortened duration of rainfall. However, a combination of storage and supply chain challenges and low returns from cereal production, coupled with land scarcity in the Western Region, where most of them are migrant farmers accounted for their decision to return to cocoa production lately. It was observed, among other adaptive responses, that some farmers plant about three times the plantain suckers they usually plant, to provide a dense temporary shade over cocoa seedlings, and resort to planting more cocoa seedlings randomly per unit area on new farms, contrary to recommended planting approach, as a form of insurance against seedling mortality. More importantly, a community-based fire response system was identified to be a major safeguard mechanism to the threat of fire. Clearly, the farmers are not replanting cocoa in the forest-savanna agro ecological landscape because it is more productive than cereals, but they believe that a low yielding cocoa is far better than a productive cereal cropping systems that offer low returns when compared to cocoa. The study brings out the sustainable livelihood challenges of the rural farmer within the context of a changing climate for appropriate policy response.     

Getting fourteen for the price of one! Understanding the factors that influence land value and how they affect biodiversity conservation in central Brazil

Biodiversity policies are suffering an implementation crisis; the roots are deeply entrenched in the unfair competition between the public and private interests for suitable versus available land. In this article we propose a value-based equivalence method for compensation for the 20% compulsory reserves in the Taquari River sub-catchments, as legally required for central savannas of Brazil. Using regression techniques we analyzed 106 land deals in the Pantanal's watershed and identified the most significant variables influencing land value. We argue that the commonly used area-for-area, compensation mechanism, where 1 ha of compulsory reserve is missing, requires another hectare protected in the same catchments, instead of counteract habitat loss, is in fact harmful to biodiversity, stimulating progressive habitat destruction. We identified the economic forces behind deforestation and habitat fragmentation in the central savannahs of Brazil and proposed a market-based approach to counteract these forces using tools already available in environmental economics. We suggest that a dollar-for-dollar reference to determine land equivalence and compensation can better counter-balance the incremental losses from habitat destruction, while providing objectivity and transparency for trading alternatives.     

基于GIS-Agent模型的武汉市土地利用变化模拟研究

综合利用GIS的空间分析功能和Agent模型的复杂系统模拟预测功能,论文尝试解决土地利用变化的模拟预测问题,以期对科学制定城市与区域规划有所裨益.在典型Agent模型"Repast3.0"基础上,构建了Repast与Openmap相结合的土地利用变化模拟及预测原型系统.基于武汉市土地利用变化的应用结果表明,GIS-Agent一体化技术是模拟预测土地利用分布变化的一种可行方案.