红壤旱地不同复种方式的生态功能评价

为了充分发挥红壤旱地的生态功能,筛选出适于红壤旱地的优化复种方式,依据3年的田间定位试验资料,从农田生态系统的生产功能、物质循环特征、能量流动特征、价值流动特征以及养地效果等方面对红壤旱地4种复种方式处理A(CK): 小麦/大豆-芝麻;处理B: 混播绿肥(油菜×紫云英×肥田萝卜)-大豆‖玉米-绿豆‖芝麻;处理C: 黑麦草-花生‖玉米-粟‖荞麦;处理D: 油菜-绿豆‖甘薯,“/”表示套作,“‖”表示间作,“-”表示接茬,“×”表示混作]的功能和效益进行了分析,并采用灰色关联度法从经济效益、生态效益和社会效益3个层次的13个指标对各复种方式进行了综合评价.结果表明: 混播绿肥(油菜×紫云英×肥田萝卜)-大豆‖玉米-绿豆‖芝麻复种模式的经济效益、生态效益和社会效益的关联度值均居第一位,经灰色关联度分析,得出其综合效益关联度值也最高,为0.847,是比较适宜在红壤旱地推广应用的高效复种方式,对今后红壤旱作区种植业结构布局和优化具有积极意义.

Ecological evaluation of different multiple cropping systems in red soil drylands.

In order to maximize the ecological function of red soil drylands and to determine the desirable multiple cropping systems, we evaluated the productivity, circulation of materials, energy and value flows in four multiple cropping systems on the basis of a consecutive three-year field experiment. Four multiple cropping systems were designed: treatment A (CK): wheat/soybean-sesame; treatment B: mixed green manure (rape × Chinese milk vetch × radish)-soybean ‖ maize-mung bean‖ sesame; treatment C: ryegrass-peanut‖ maize-millet‖ buckwheat; and treatment D: rape-mung bean‖ sweet potato; where interplanting was expressed as ‘/’, intercropping as ‘‖’, planting after harvest as ‘-’, and mixed cropping as ‘×’. Thirteen variables were employed to compare economic, ecological, and social benefits among the four cropping systems using grey relational analysis. The results showed that ‘mixed green manure (rape × Chinese milk vetch × radish)-soybean‖ maize-mung bean‖ sesame’ exhibited the highest grey relational degrees in terms of economic, ecological, and social benefits, and a highest grey relational degree at 0.847 in the integrative benefit. This treatment was the best multiple cropping pattern suitable for red soil drylands. Thus, this cropping system could have a positive impact on the layout and optimization of the structure of agricultural production in red soil dryland regions in the future.