摘要
在大田条件下,探讨了不同降水年型下灌溉模式对紫花苜蓿产量的影响及土壤水分动态。结果表明:在京南地区,紫花苜蓿达到高产的最佳需水量为750～800mm之间。在枯水年,前3茬苜蓿产量随降雨和灌溉量的增加而增加,第4茬则降低,采用在苜蓿返青及1、2茬苜蓿刈割后灌水且每次灌水75mm(W3)的灌溉模式有利于苜蓿高产;在丰水年,第1、2茬苜蓿产量随降雨和灌溉量的增加而增加,3、4茬则降低,采用在苜蓿返青及第1、2茬苜蓿刈割后灌水且每次灌水50mm(W2)的灌溉模式有利于苜蓿高产。枯水年4～9月土壤水分变化基本呈W型,而丰水年为V型。枯水年和丰水年雨季前土壤水分均缓慢减小,枯水年雨季后土壤水分变化平缓,而丰水年雨季后土壤水分增加明显。
Under field conditions, effect of irrigation under different annual precipitation patterns modes on alfalfa yield and dynamic changes of soil moisture were analyzed. The results showed that the optimal amount of water supply （the optimal amount of water requirement） for maximal yield of alfalfa was between 750ram and 800ram in the south of Beijing area. Irrigation and rainfall significantly improved the dry matter of the first, second and third cut alfalfa and decreased the dry matter of the fourth cut alfal- fa in dry year, while they significantly improved the dry matter of the first and second cut alfalfa and de- creased the dry matter of the third and fourth cut alfalfa in wet year. To achieve higher alfalfa yield, W3 （irrigation amount 75 mm per time, three times in a year） and W2 （irrigation amount 50 mm per time, three times in a year）irrigation modes should be recommended in dry year and wet year, respectively. Dy- namic changes of soil moisture from April to September in dry year showed W type, while in wet year showed V type. Soil moisture was slowly decreased before the rainy season in both dry year and wet year. In the rainy season, however, soil moisture changed gently in dry year and increased significantly in wet year.
出处
《中国草地学报》
CSCD
北大核心
2013年第5期46-52,共7页
Chinese Journal of Grassland
基金
奶牛营养调控与粗饲料高效利用关键技术(2012BAD12B02)
作者简介
李新乐（1989-），男，内蒙古巴彦淖尔人，在读硕士研究生，研究方向为草地资源利用与保护，E—mail：nkylxl@126．com．
通讯作者，E—mail：houxyl6@126．com
