毛乌素沙地农牧生态系统能值分析与耦合关系

针对毛乌素沙地脆弱农业生态系统生产力实际,根据复合生态系统耦合理论,借助能值理论及分析方法,选择毛乌素沙地偏农区的榆阳区和偏牧区的乌审旗为比较研究对象,对两地近27a的农牧耦合系统初级生产力、次级生产力及系统耦合状况进行了对比分析,探讨性提出了区域农牧系统耦合程度的演变规律。结果表明,榆阳区是偏农型的农牧耦合产业发展模式,乌审旗是偏牧型的牧农耦合产业发展模式;榆阳区有以耗粮型生猪、禽类生产为主的势头,乌审旗有以节粮型草食动物生产为主的势头;榆阳区和乌审旗的初级生产力、次级生产力及A(有效能值利用率)、B(单位低质能产品转化成高质能产品率)、SCD(系统耦合度)值均沿时间序列增大,且SCD值有呈三阶段型增长的规律性。依据研究结果,最后提出了毛乌素沙地农牧生态系统耦合发展的途径,以期能为沙地农牧生态系统稳健发展提供可靠的理论支撑与政策导向。

The coupling relationship and emergy analysis of farming and grazing ecosystems in Mu Us sandland

Aiming at real productivity of frail farming and grazing ecosystems in Mu Us sandland, basing on coupling theory of complex ecosystem, Uxin banner where grazing is dominant and Yuyang district where farming is the main character were selected as research object by means of using emergy theory and analytic methods, it analyses the primary productivity, secondary productivity and the coupling status of the farming and grazing system in those two areas for 27 years. And it comes up with a possible evolvement regulation of the extent of agro-ecosystem coupling. The results show that the industrial development model of Yuyang distric is farming-dominant, but Uxin banner is the grazing-dominant; Yuyang district has the tendency of pig, poultry production, but Uxin banner has the tendency of herbivorous animal production; the primary productivity, secondary productivity, A, B and SCD in those two areas are all increasing, and the SCD has the increase in the shape of "three-stage" in 27 years. In conclusion, this paper brings forward the developmental methods of farming and grazing ecosystems coupling in Mu Us sandland, it is expected to provide credible theory supports and direction to healthy development of the farming and grazing ecosystems.