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岷江上游,重峰叠障,雪山起伏,水量丰沛,坡陡流急,蕴藏着丰富的水力资源和森林资源,是庇护“天府之国”的绿色长城和灌溉川西万顷良田的泉源.近年来,水文气象特征发生的变化,愈来愈被人们所注意.本文欲就岷江上游水文气象特征的变化来谈森林的防护效益.一、岷江上游水文气象特征的变化.岷江上游水文气象特征的变化主要有以下几点:1.地方气候趋于恶化,雪线上升,积雪减少,风速增大,旱灾增多.据统计,松潘、南坪、黑水和茂汶的风速至七十年代,分别比五十年代以来的全年平均
The upper reaches of the Minjiang River, heavy mountain overlying barrier, snow-capped mountains and downs, abundant water, steep slope flow, rich in water resources and forest resources, is to protect the “Great Wall of Natural Lands” and irrigation fertility farmland in western Sichuan .In recent years, hydrological meteorology The characteristics of the changes occur, more and more people pay attention to.This paper aims to discuss the changes in the upper reaches of the Minjiang River hydrological meteorological characteristics of the forest protection benefits.Analogy of the Minjiang River hydrological meteorological characteristics of the upper reaches of Minjiang River hydrological meteorological characteristics of the main changes are What time points are: 1. The local climate tends to deteriorate, the snow line goes up, the snow cover decreases, the wind speed increases, and the drought increases. According to the statistics, the wind speeds of Songpan, Nanping, Heishui and Maowen are higher than those in the seventies Since the annual average