The influence factors and ranges of water requirements (WR), water consumptions (WC), water requirement rates (WRR), water consumption rates (WCR) and water use efficiencies (WUE) of alfalfa (Medicago sativa L. ) were studied. The WR and WC of alfalfa differed at the different climatic region and year. Increasing cutting frequency could reduce the WR of alfalfa. The WC of alfalfa were improved with the increasing irrigation amount to some extent, and different under different irrigation patterns. The ranges of WR and WC of alfalfa in the whole growing season were about 400 to 2 250 mm and 300 to 2 250 mm, respectively. The WRR and WCR were different at different climatic region and year, growth cycle and development stage. The WRR of alfalfa were positively relative to the atmospheric evaporation power, and the WCR positively relative to the soil moisture content. Increasing cutting frequency could reduce the WRR of alfalfa. The WCR of alfalfa were up following the increasing irrigation amount to some extent, and different under the different irrigation patterns. The ranges of WRR and WCR of alfalfa during the whole growing season were 3 ~ 7 mm/d and 2 ~ 7 mm/d, respectively. The highest WRR in a short period was 14 mm/d. The WUE were different under the condition of different climate region and year, amount and patterns of irrigation and fertility, and growth cycles, and higher of 2-year-old and over alfalfa than 1-year-old one. But there was no significant difference between cultivars. Under the normal field conditions, the ranges of the WUE in bi-omass and in economic yield (14% water content) of 1-year-old alfalfa were about 8 ~ 12 kg/(mm · hm2) and 9~14 kg/(mm · hm2), and of 2-year-old and over were 12~25 kg/(mm · hm2 ) and 14~29 kg/(mm · hm2) , respectively.
国家科技期刊平台
NSTL
维普
万方数据
