黄土丘陵区旱地作物水分生态适应性系统评价

Systematic analysis on water ecological adaptability of upland crops in loess hilly zone

根据调查资料和田间试验结果 ,系统地分析了旱地不同作物生长发育与降水分布的时序关系、旱地作物水分潜在利用率和旱地主要作物水分供需平衡与错位特征 ,并利用水分生态适应性数学模型 ,对宁南黄土丘陵区主要作物的水分生态适应性进行了定量评价 .结果表明 ,秋熟作物生长发育与降水分布耦合性较好 ,夏熟作物生长发育与降水分布耦合性较差 .不同作物的降水潜在利用率存在差异 ,其基本规律是 :多年生牧草 >薯类作物 >谷类作物 ;秋熟作物 >夏熟作物 .作物的水分满足率和生态适应性 ,秋熟作物优于夏熟作物 ,丰水年份优于干旱年份 .旱地 6种主要作物的水分生态适应性指数排序依次为 :谷子 >马铃薯 >糜子 >胡麻 >豌豆 >春小麦 .

Based on the survey and experimental results,this paper analyzed the time-sequence relationship between crop growth and rainfall distribution,and the potential water use rate,water supply-demand equilibrium and deficit features of different upland crops in the loess hilly zone of south Ningxia.The model of water ecological adaptability index (WEAI) was proposed to evaluate these features of upland crops.The results showed that autumn crops were superior to summer crops in the coupling characteristics between crop growth and rainfall distribution.There were also differences in rainfall potential use rate among crops,the order being: perennial crops>root and stem crops>grain crops; autumn crops>summer crops.The water satiety rate and water ecological adaptability were higher for autumn crops than for summer crops,and higher in rainy years than in dry years.In line with water ecological adaptability index,the 6 main crops could be put in order of millet>potato>panic>flax>pea>spring wheat.The results of this study may provide theoretic basis for drawing up the decision scheme of cropping system in upland regions.