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一、林网具有改善农田小气候,创造适宜作物正常生长的环境条件,促进作物高产稳产。 1.能降低风速50％,改变害风性质,变害风为益风。有效防护距离为林带树高的15～20倍以内。 2.能调节温度。夏天平均降低1.4℃,秋季0.2℃。 3.减少蒸发量38％;降低蒸腾强度18％。 4.提高相对湿度11％。 5.增加辐射热20％。二、大风和干热风使小麦减产18％。三、一个林网能提供209立米的木材,平均每亩2.16立米。平均每亩每年木材收入28元。四、林带胁地范围大致在10米以内,胁地面积占总面积的15％以下。对产量的影响,夏收作物减产14％;秋季作物减产20％以上,重者50％。五、林网增产作用显著。扣除胁地减产的部分,仍然增产。如小麦净增55％,玉米36％,谷子21％,红薯85％。
First, Lin network has to improve the microclimate of farmland, to create suitable environmental conditions for the normal growth of crops, and to promote high and stable crop yield. 1. Can reduce the wind speed 50%, change the nature of harmful wind, change harmful wind is beneficial wind. The effective protection distance is 15 ~ 20 times of the forest tree height. 2. Can adjust the temperature. The average decrease of 1.4 ℃ in summer and 0.2 ℃ in autumn. 3. Reduce the evaporation 38%; reduce the transpiration intensity 18%. 4. Increase the relative humidity of 11%. 5. Increase radiant heat 20%. Second, the wind and dry hot wind wheat yield by 18%. Third, a forest network can provide 209 cubic meters of wood, an average of 2.16 cubic meters per mu. The average annual timber revenue per mu 28 yuan. Fourth, the scope of forest belt threatened roughly within 10 meters, threatening land area of less than 15% of the total area. The impact on output, summer harvest crops cut 14%; autumn crop more than 20%, in severe cases 50%. Fifth, Lin net significantly increase production. Excluding the part where the threat of yield reduction still increases. Such as wheat net increase of 55%, 36% of corn, millet 21%, sweet potato 85%.