草业学报2012，Vol.21Issue(5)：204-212,9.
半干旱黄土丘陵区施肥对退耕地紫花苜蓿生物量的影响
Effect of fertilization on biomass of alfalfa in returned farmland in semiarid loess hilly area
摘要
Abstract
For increasing the aboveground biomass of alfalfa (Medicago sativa) in returned farmland and pro-longing its degradation time, the mixed fertilization experiment of nitrogen and phosphate fertilizer was conducted two times in 2007-2008, on alfalfa grassland that has been planted for five years in Longtan catchment, Anding district, Dingxi city. The result .showed that nitrogen fertilizer has no obvious effect on increasing the growth conditions and biomass of alfalfa. However, phosphate fertilizer has significant influence on promoting the alfalfa's growth and increasing biomass. And the mean biomass of fertilized alfalfa in 2007 and 2008 was 1. 62 and 1. 15 times the biomass of control alfalfa respectively. The highest biomass of alfalfa was appeared when phosphate fertilizer rate was highest of 12 kg/667 m2. The mean fresh biomass of alfalfa can a-chieve 18 240 kg/ha on seventh year. The growth conditions and biomass of alfalfa on sunny-slopes was better than that on shady-slopes,and its mean fresh and dry biomass were 1. 49 and 1. 43 times the biomass of shady-slopes respectively. In the semiarid loess area with 400 mm annual precipitation, the biomass of alfalfa harvest was mainly produced by the 1st harvest and it accounted for about 75% of annual biomass, whereas the biomass of 2nd harvest was small and accounted for about 25%. So twice per year for alfalfa harvest is optimized in this area.关键词
紫花苜蓿/施肥/生物量Key words
alfalfa/fertilization/biomass分类
农业科技引用本文复制引用
蔡国军,张仁陟,柴春山..半干旱黄土丘陵区施肥对退耕地紫花苜蓿生物量的影响[J].草业学报,2012,21(5):204-212,9.基金项目
国家"十一五"科技支撑计划课题"黄土丘陵沟壑区生态综合整治技术开发"(2006BAC01A06)资助. （2006BAC01A06）
