(强)热带风暴下海岸带梨园林网防护效益的研究

Study on benefits of pear orchard under the protection of coastal windbreak networks against violent tropical storm

根据海岸带梨园林网遭受 11号强热带风暴侵害后果园内落果情况的调查资料 ,研究了梨园林网的防护效益。结果表明 :( 1)主林带背风面不同距离处梨的落果、减产指标随着距离的增加呈低—高—较低的曲线变化规律 ,而梨的保护量和保护率则呈相反的变化规律。 ( 2 )梨园林网的有效防护范围为 0 .5H～ 16H和 2 4H～ 2 8H(H为主林带平均树高 ) ;与无林网梨园相比 ,梨园林网内梨的产量增加了 2 194.42kg/hm2 ,增产率为 2 3.93% ,经济损失量减轻 145 0元 /hm2 。

According to the data of dropped fruits in pear orchard after infringement of tropical storm, the paper studied the benefits of pear orchard under the protection of coastal windbreak networks. The results showed that: (1) Quantity of dropped fruits and target for reduced production formed a curve with corresponding points of low, high and lower level with the increase of the distance from the main winbreak zone. But the curve formed by protective yield and protective ratio suggested an opposite shape to the former.(2) The effective protection zone of pear orchard windbreak networks, ranged from 0.5H (the hight of main winbreak zone) to 16H and 24H to 28H. Compared with open pear orchard, the pear yield increased 2 194.42 kg/hm 2,economic losses reduced 1 450 yuan/hm 2,and the increases rate was 23.93%.