Research On Water Requirements Rate Of Alfalfa And Leymus Chinens In Basha District

The research conducts from 2006 to 2007 in Saibei Area of Hebei province, with alfalfa planted in 2006 and leymus chinens planted in 2007 as the research object. The influence of irrigation and water requirement on hay production, water use efficiency and water consumption coefficient of two plants are studied.1.Alfalfa are irrigated 0mm, 200mm and 400mm respectively. It is found out that the ecology characteristics of two plants, such as hay production, water use efficiency and water consumption coefficient, plant height, plant number per area, leaf area are all changed in certain degree. More irrigation is favorable for the increase of hay production, plant height, plant number per area and leaf area. Besides, those plants of whole-life irrigation enjoy marked plant number per area in contrasted with those without irrigation. The hay productions of 200mm irrigated area and 400mm irrigated area are respectively 8210.6㎏/hm2 and 13507.7㎏/hm2, water requirement as 475.3mm and828.2mm, water useage efficiency based on biological yield as 9.83 kg/ hm2.mm and 16.76kg/ hm2.mm, water useage efficiency based on economic yield as11.43,19.49kg/ hm2.mm water consumption coefficients based on biological yield as 1017.44and 875 and water consumption coefficients based on economic yield as596.5,513.03.2.The soil humidity of artificial pasture of alfalfa in dry season is rather low. The coming of raining season brinngs the the increase of soil humidity , with superficial soil fastest, mid and deep soil followed. Generally, the soil humidity increases in June by irrigation without marked differnces comparing with May. But the soil humidity of unirrigated area above 30cm is lower than May. The others increase.The rainy season comes in July.It was the second irrigation on July 10th.All the soil humidity of every lay increases except unirrigate.The soil humidity above 50cm in August are lower than in July of unirrigation,while the soil humidity under 50cm are low . The 50-70cm soil humidity which are irrigated 200mm are high inJuly. The 60-80cm soil humidity are higher than in July.The others are low. The 0-10and10-20 soil humidity which are irrigated 400mm are high in July.The others are significant in July. Every soil humidity of different treatments in September are low than in August. From May to September, soil humidity of Alfalfa growth season increased except unirrigation. 3.Alfalfa are irrigated 0mm, 200mm and 400mm respectively. It is found out that the ecology characteristics of two plants, such as hay production, water use efficiency and water consumption coefficient, plant height, plant number per area, leaf area are all changed in certain degree. The plant height, leaf area and subterranean ecology characteristics of leymus chinen are especially influenced. Much irrigation is favorable for the growth of plant and the increase of leaf, less irrigation being favorable for tillering and subterranean ecology increase. The hay production of three areas are 1137.82㎏/hm~2,878.93㎏/hm~2 and 483.46㎏/hm~2 and water useage efficiency based on biological yield as 1.71 kg/ hm~2.mm, 1.89 kg/ hm~2.mm and 1.67kg/ hm~2.mm in 2007.4.The soil humidity of leymus chinens in 2007 is presented as followings. The soil humidity in initial stage of leymus chinens growth is rather low. The first irrigation in June influences much to the superficial soil and little to deep soil. The second irrigation in July puts all levels of soil are of more humidity than June. As there is no irrigation in August, soil humidity of all levels in unirrigated area decrease, but the soil humidity in deep soil level of irrigated area increases.It is stage of leymus chinens growth from June to August,all the soil humidity about different treatments do not wane.