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2006年四川发生了百年一遇的特大干旱。按照自然地理条件相近、森林覆盖率有较大差异的原则,采用对比分析方法,于干旱末期,调查了四川盆地丘陵区13对乡镇(森林覆盖率高的乡镇森林覆盖率为28.26%～56.23%,平均为38.22%,相对应的低的乡镇森林覆盖率为5.65%～27.10%,平均为16.41%)内的溪河流量、堰塘和水井干枯情况以及人畜饮水现状。结果表明,在干旱季节,森林覆盖率低的乡镇溪河断流率平均为69.1%,断流天数平均为52 d;而覆盖率高的乡镇溪河断流率平均为25.5%,比前者少43.6%,断流天数平均为35.3 d,比前者少16.7 d,溪河平均断流起始时间比前者推迟17.3 d。森林覆盖率低的乡镇堰塘、水井平均干枯率分别为62.5%、70.0%,新打水井中,出水井率为48.2%;而覆盖率高的乡镇堰塘、水井平均干枯率分别为40.9%、43.7%,比前者分别低21.6%、26.4%,新打水井中,出水井率为57.7%,比前者高出9.5%。人畜饮水困难数占总人畜比例,覆盖率高的乡镇比覆盖率低的乡镇分别少24.0%、23.2%。
In 2006 there was a serious drought once in a century in Sichuan. In accordance with the principle of similar natural and geographical conditions, there is a big difference in forest coverage. Through comparative analysis, 13 pairs of towns and villages in the hilly area of Sichuan Basin (the forest coverage of villages with high forest coverage are 28.26% -56.23% , With an average of 38.22%, corresponding to a low forest cover rate of 5.65% ~ 27.10% in villages and towns with an average of 16.41%), the dry flow of weirs and wells, and the status quo of drinking water for people and livestock. The results showed that in the dry season, the average flow-off rate of towns and townships with a low forest coverage was 69.1% and the average number of flow-cut days was 52 days; while the average coverage rate of towns and towns was 25.5%, less than the former 43.6%. The average number of cut-off days was 35.3 days, 16.7 days less than the former, and the average river cutoff start time was 17.3 days later than the former. The mean dry rate of townships and weirs with low forest coverage was 62.5% and 70.0% respectively, and the rate of wells in the newly drilled wells was 48.2%. The mean dry rates of townships and weirs with high coverage were 40.9% , 43.7% respectively, 21.6% and 26.4% lower than the former, respectively. In the newly drilled wells, the discharge rate was 57.7%, 9.5% higher than the former. The number of people and livestock in drinking water accounts for the proportion of total human and livestock, and the towns with high coverage rate are 24.0% and 23.2% less than the towns with low coverage rate respectively.