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农田防护林在防止风沙、干旱、改善农田小气候、调节农田生态因子等方面,对农业稳产高产的效益是十分巨大的。为了探讨农田防护林的效益,我们从1980—1982年,在我县大师大队进行了观测、调查。现将观测结果,初报如下: 一、自然概况乾安县地处松辽平原中部。地理位置:东经124°1′,北纬45°。属黄土台地,海拔140—150米。少数沙臣略起伏,其余较平坦。春季干旱多风,一般5—6级,也出现8—9级,个别年份有11级大风。年平均降水量400毫米。年蒸发量1800毫米,为降水量的3—4倍。年平均气温4—5℃。≥10℃积温2800—2900℃。无霜期140天左右。
Farmland shelter belts in the prevention of wind and sand, drought, improve the microclimate of farmland, regulate farmland ecological factors, the benefits of stable and high-yield agriculture is very huge. In order to explore the benefits of farmland shelterbelt, we observed and investigated in our county master brigade from 1980 to 1982. Now the observations, the first report is as follows: First, the natural profile Qian’an County is located in the central Songliao plain. Geographic location: longitude 124 ° 1 ’, latitude 45 °. Is a loess plateau, elevation 140-150 meters. A handful of sand Chen slightly ups and downs, the rest is relatively flat. Spring drought windy, generally 5-6, also appear 8-9, individual years have 11 gale. The average annual rainfall of 400 mm. Annual evaporation of 1800 mm, 3-4 times the amount of precipitation. The average annual temperature 4-5 ℃. ≥ 10 ℃ accumulated temperature 2800-2900 ℃. Frost-free period of about 140 days.