摘要
研究了三种供水处理（W1、W2、W3灌溉量分别近似为650mm、580ram、500mm）对河西地区种植的紫花苜蓿第1年的生长状况、株高、叶面积、地上生物量、地下生物量及其营养品质的影响。结果表明，w1下生长速率最大，比W2、W3分别高9．5％和33．3％，初花期生长速率差异较大；随水分供应量增加，叶面积指数增大，开花期达到最大值，之后下降，整个生育期内叶面积指数变化呈抛物线形状。地上生物量与水分供应量呈线性正相关；根系主要分布在土壤表层0-40cm。w1和W2对紫花苜蓿的营养品质影响差异不明显，但W3的影响显著。同一水分处理下，蛋白质（CP）与脂肪（CE）含量随生育期延迟而减少，粗纤维（CF）含量则增加。在该地区灌溉选择W2处理（灌水580mm），即保持在最大土壤饱和持水量的70％，既能保证紫花苜蓿较高的地上生物量和较好的品质，又能节约当地的水资源。
Growth status of alfalfa in the sowing year in Hexi region, including leaf area index（LAI）, height,biomass, quality, were studied with three water supply treatments（W1,W2,W3）. The results showed that growth rate of alfalfa with W1 treatment was increased by 9.5% and 33.3% compared with treatment W2,treatment W3, respectively. There was a significant difference at early stage of blooming. With water supply increasing, LAI increased and reached peak, subsequently declined. The change of LAI showed parabola shape in whole growing period. There was a linear positive correlation relationship between aboveground biomass and water supply. Most roots distributed in 0- 50cm under ground. There were no differences in nutrition quality between water supply treatment W1 and W2. Treatment W3 affect- ed nutrition quality significantly. The content of crude protein and crude fat decreased, but crude fibre increased with the same water supply treatment. The treatment W2（irrigating 580mm）, holding of 70% the most saturation water capacity, can make the aboveground biomass of alafalfa higher and forage quality better, and also can save water.
出处
《中国草地学报》
CSCD
2008年第5期59-64,共6页
Chinese Journal of Grassland
基金
国家高技术研究发展计划(“863”计划)(2006AA10Z132)
国家科技支撑计划(2006BAC18B04-1)项目
深圳市城市管理局项目
贵州省科技厅基金项目(Z063064)
