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我省造林一般都在春秋两季进行,但对西部干旱地区的盐碱地,这时造林往往成活率低,收不到成林效果。这是因为这个地区的气候特点是在春季造林时,气温高,近地层温度有时可高达40℃以上,昼夜温差变化大,降水量少,年平均降水量在400—450毫米,多集中在雨季(7～8月),占全年降水的58%以上,而造林季节(4～6月)降水量只占全年降水量的11%。蒸发量大,4～6月分的蒸发量约占全年的49%,使土壤干燥。春季干旱风大而持久,有时可持续到6月初,这样,就使林木在生长初期,加速了叶
Afforestation in our province is generally carried out in spring and autumn, but for saline-alkali lands in the arid areas of the western part of the country, afforestation often has a low survival rate and can not receive the forest-planting effect. This is because the climatic characteristics of this area are high temperatures in afforestation in spring and sometimes the temperature of the near-surface layer can reach as high as above 40 ℃. The temperature difference between day and night varies greatly and the precipitation is small with the annual average rainfall of 400-450 mm, mostly concentrated in the rainy season (July-August), accounting for more than 58% of the annual precipitation, while the afforestation season (April-June) only accounted for 11% of the annual rainfall. Evaporation, 4 to 6 months of evaporation accounted for about 49% of the year, making the soil dry. The spring droughts are large and persistent, sometimes up to the beginning of June, so that the tree grows early and leaves are accelerated