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在简要评述经济阈值在森林有害生物,尤其是蛀干害虫综合治理中的局限性和特点的基础上,针对不同林种的主要经营目标,首次提出了防护林生态阈值的概念,分析了生态阈值与经济阈值的区别和特点.对宁夏青铜峡市防护林中的杨树天牛生态阈值进行了初步的研究.结果表明:羽化孔可以作为合作杨生态阈值的特征指标值;在甘城子乡,树龄为8～10a,合作杨与新疆杨的混交比例为1∶3,并在其它病虫危害甚轻和非生物因素的不良影响可忽略不计时,合作杨的杨树天牛生态阈值是48个羽化孔,其区间值为[4,6].
On the basis of briefly reviewing the limitations and characteristics of economic thresholds in forest pests, especially the management of borer pests, the concept of ecological threshold for shelterbelts was proposed for the first time for the main business objectives of different forest types. The relationship between ecological thresholds and Economic threshold and the characteristics of ecological shelterbelt in Ningxia Qingtongxia City.The results showed that the eclosion hole can be used as the characteristic index value of ecological threshold of cooperative poplar in Ganchengzi Township, 10a, the ratio of mixed poplar to Xinjiang poplar was 1: 3, and the ecological threshold of poplar poplar was 48 eclosion holes when the adverse effects of other pests and diseases were very negligible and abiotic factors were negligible. The interval The value is [4,6].