Managing the Tropical Agriculture Revolution

ABSTRACT

Industrial production of beef, soybeans, cotton, and biofuels is expanding into the tropical latitudes of South America and may soon reach tropical Africa in the most important agricultural transition since the Green Revolution. This shift is driven by the shortage of land suitable for expansion of cultivation and grazing in the temperate zone, increased global demands for agricultural commodities, the rising price of petroleum, and technological advances. At risk are some of the world's most ecologically and culturally-rich landscapes in the world, such as the Amazon rainforest, the Cerrado woodland complex, and African savannas. A strategy for reducing the negative ecological and social impacts of this transition could harness the rising environmental and social standards imposed by many importers and purchasers of agricultural commodities, similar reforms underway among “Equator” banks, growing corporate governance, and Brazil's prominence in international diplomacy. Integrated certification of commodity sanitation, compliance with rigorous environmental standards, and sound labor practices could become the norm for participation in commodity markets. These reforms in agro-industrial behavior could be reinforced by trade agreements and strategic support from non-governmental organizations.     

赤道海域茎柔鱼栖息地月间分布及与环境因子的关联

茎柔鱼是我国主要捕捞的经济头足类之一,探究其栖息地的空间分布与环境的关系可以帮助企业有效利用和开发渔场。本研究利用2012~2018年我国鱿钓渔船在赤道海域的捕捞数据,选取海表面温度(Sea Surface Temperature,SST)、海表面盐度(Sea Surface Salinity,SSS)、叶绿素浓度(Chlorophyll-a, Chl-a)、净初级生产力(Net Primary Production,NPP)、光合有效辐射(Photosynthetically Active Radiation,PAR)、涡旋动能(Eddy Kinetic Energy,EKE)和海平面异常(Sea Level Anomaly,SLA)7个环境因子以月为单位建立最大熵模型,分析赤道海域茎柔鱼栖息地的月间时空变化及环境因子的影响差异。结果表明：各月模型模拟的适宜栖息地空间分布与实际作业位置较好吻合,1~8月份适宜栖息地向东南海域移动,随后月份逐渐转向西北海域。环境因子贡献率表明各月间环境因子对茎柔鱼栖息地分布影响具有明显差异,关键环境因子的适宜范围呈现出明显的季节变化,但各月对SST的空间分布表现出较高的敏感性。研究表明,最大熵模型能较好模拟茎柔鱼栖息地的分布情况,月间时空分布特征显著,海流和涡旋可能会对茎柔鱼的渔场形成和分布具有较大影响。