基于能流的生态农户分析与设计方法研究——以川北丘陵区一肉狗养殖户为例

Analysis and design methods of ecological farmer household based on energy flow: A case study of dog-breeding farmer household in northern Sichuan

为了探索基于能流理论的生态农户分析与规划设计方法,以四川北部丘陵区一个肉狗养殖户为研究案例,运用能流理论与分析方法,对该农户的生态系统能流进行诊断分析,进而对两种基于肉狗养殖的新生态农户模式设计方案进行系统结构分析、组分模拟与综合效益的评价与比较。结果显示:原生态农户是一个有机型系统,但能量转化率很低,仅为0.62%;能量输出能力较差,种植子系统与养殖子系统的能量产投比分别为3.93和0.32;能量循环指数也较低,为0.70,低于国内20世纪70年代末的水平。该系统应适当增加有机能的投入以改善系统的能流状况。两种基于肉狗养殖的新生态农户设计模式的系统自我维持能力会增强,能量转化效率明显提升,模式一为1.02%,模式二为1.13%;能量循环指数也明显提高,分别为0.83和0.84;种植子系统和养殖子系统能量产投比明显提升,分别为4.80、0.48和4.93、0.46。新设计生态农户模式的综合效益均高于原生态农户。模式一的综合效益高于模式二,最终形成了比较严谨的生态农户设计方案。研究发现,基于能流理论对原农户生态系统进行诊断与分析,并结合多种新生态农户设计模式的能流模拟与综合效益比较,为生态农户的系统分析与优化设计提供了一种好方法与解决方案,为提高农户生态系统的能量输出能力和综合效益的最优化提供了现实的参考依据。

A dog-breeding farmer household in northern Sichuan was used as a case to analyze and design an ecological farm household based on energy flow theory.The energy input-output of original ecological farmer household systems in 2008 was initially analyzed and diagnosed for ecosystem structures and benefits.According to the analysis results,two new design modes of farmer household ecosystems modeled with dog-breeding were proposed.Comprehensive input-output energy and benefits were comparatively analyzed,simulated and compared with the original system.The results showed that although the original ecological farmer household system was an organic ecosystem,its energy conversion rates and output capacity were very low.The ratios of solar energy and average energy input-output of both planting and breeding subsystems along with the energy cycle index of the original ecological farmer household system were 0.62%,3.93,0.32 and 0.70,respectively.This indicated lower organic energy input and suggested necessary improvements in energy flows.Compared with the original ecosystem,the two new designed ecosystems showed higher self-sustainability capacity and energy conversion efficiency.The ratios of solar energy and average energy input-output of both planting and breeding subsystems and the energy cycle indices of the new designed ecosystem modes 1 and 2 were 1.02% and 1.13%,4.80 and 4.93,0.48 and 0.46,0.83 and 0.84,respectively.The comprehensive benefits of the designed mode 1 were higher than those of mode 2.The above analyses and results suggested that the study presented a very rigorous design of ecological farmer household.The results also contributed to developing new optimized design methods for farmer household ecosystems based on energy flow simulations and comprehensive benefit comparisons.More specifically,the analysis and design method of ecological farmer household in this study provided a realistic reference base for improving ecosystem energy output and benefit optimization.