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本文以李家洲林场长江外滩杨树林分为代表,研究了滩地林农复合生态系统对水淹环境的反应,其主要结论是:1.幼林成活与淹水状况和林木本身的生长状况密切相关,成活率与淹水时间呈负相关,与林木直径呈正相关,回归模型为y=100.7033+3.6586X_1-0.4547X_2-3.4106Xa;2.淹水对幼林生长有明显影响,淹水40天以后每增加10天,生长量平均下降10%,淹水对3年生以上的林分影响不大;3.100天以内的淹水时间越长,钉螺分布密度越大,林地钉螺主要是受江水携螺情况的影响,汛期过后,钉螺分布密度呈上升趋势。
In this paper, the poplar stands on the beach of the Yangtze River in Lijiazhou Forest Farm were used as representative to study the response of the forestland agro-ecosystem to the submerged environment. The main conclusions are as follows: (1) The survival and flooding of the young plantation are closely related to the growth of the forest itself, The flooding time was negatively correlated with the diameter of the tree, and the regression model was y = 100.7033 + 3.6586X_1-0.4547X_2-3.4106Xa. 2. The flooding had a significant effect on the growth of young forests, and every 10 days after flooding for 40 days, The average amount of growth decreased by 10%, and the flooding had little effect on the stands above 3 years old. The longer the flooding time was within 100 days, the greater the density of snails distributed. The snail was mainly influenced by the situation of snail infestation. After the flood season , Snail distribution density is on the rise.