基塘生态农业工程模式的能值研究

应用能值分析方法及最新推出的评价系统可持续发展能力的能值指标(EISD),分别对珠江三角洲地区的三水市的3种基塘生态农业工程模式进行系统层和子系统层的能值比较研究。分析评估结果为:模的可持续发展性能(EISD)最强。其EISD比模式、分别高出58.3%和29.7%;种植业子系统经济效益好,但影响环境,是模式内可持续发展性最差的子系统;畜牧业子系统生产环效果不佳,但增益环效果明显;渔业子系统经济效益好,环境影响减小,是系统内可持续发展性最强的子系统,引入翘嘴鳜的生态经济边际效益显著。研究表明,基塘模式是实现农业可持续发展的一大方向,发展应走面向市场,不断完善内部循环的道路

Emergy Study on Dike-Pond Eco-agricultural Engineering Modes

Three different dike-pond eco-agricultural engineering modes are studied with emergy analysis method combined with the latest emergy index for sustainable development (EISD) through system level and subsystem level in south China. The dike-pond systems are separated into planting subsystem, pig-breeding subsystem and fishery subsystem. The result is that mode Ⅲ(melon-melon-cabbage-pig-six domestic fishes combined with Siniperca chuatsi B.) is the best one on sustainable development. The EISD of mode Ⅲ (3.62) is 0.583 times higher than that of modeⅠ(melon-melon-cabbage-six domestic fishes) and 0.297 times higher than that of mode Ⅱ(melon-melon-cabbage-pig-six domestic fishes). With higher economic benefits but much higher environmental impact, the sustainable development potential of planting subsystem is the lowest. Although the economic benefit of pig-breeding subsysten is not higher, its indirect benefit is good. With higher economic benefit and lower environmental impact, the sustainable development potential of fishery subsystem is the best among the three subsystems. The result shows that perfect agricultural engineering modes should try to meet the social economic need and to realize local roundup characteristics at the same time.