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本文针对１９９７ 年度四川盆北山丘区遭遇的严重旱情，探讨了阆中市岳家沟流域农林复合系统内的水分亏缺及其与农经作物生物生产力的关系，分析了不同林带距离对林带＋ 水稻复合模式作物产量的影响，结果表明：土壤有效持水量和土壤相对含水量（ＲＷ ）是土壤抗旱性能的重要指标，土壤一定的肥效性有利于土壤抗旱性能的提高；在连续干旱４０天后，系统内各农林复合模式土壤水分亏缺极为严重，并对花椒成活和生长、大春作物产量及产品的经济性状构成了严重的影响，其中花椒成活率为６０．７％ ～７５．０％ ，各大春作物相对减产幅度为玉米３０．９％ ，花生４６．０％ ，水稻２８．９％ ～６２．２％ ，棉花２３．６％ ～５９．３％ ，表现出整个系统综合抗旱能力较差；在水分亏缺之下，不同林带距离水稻生物生产力差异显著，并表现出林带对农作物的光胁地在一定范围内并不表现为负效益而相对具有增产的作用。
In this paper, according to the severe drought encountered in the hills and valleys in Sichuan basin in 1997, the relationship between water deficit and its biological productivity in the Yuejiagou watershed in Langzhong City was discussed. The results showed that the effective water holding capacity of soil and the relative water content (RW) of soil were important indexes of soil drought resistance. Some fertilizer efficiency of soils was beneficial to the improvement of soil drought resistance. After 40 days of continuous drought, Soil and water deficit in agroforestry model was extremely serious, which had a serious impact on the survival and growth of Chinese prickly ash, the yield of spring crops and the economic traits of the products. The survival rate of pricklyash was 60.7% -75.0% The relative yield reduction of spring crops was 30.9% for maize, 46.0% for peanut, 28.9% -62.2% for rice and 23.6% -59.3% for cotton, which showed that the whole system had poor comprehensive drought resistance ability. Under the condition of water deficit, the difference of biological productivity of different forest belts was significant And forest crops exhibit Shading light is not within a predetermined range showed negative results with relatively increase effect.