摘要
我们应用振动机,对高大树上马尾松毛虫幼虫数量和虫龄及其分布进行了调查研究。试验松树高5.0—10.2m,胸径15—25cm。振动机安装在离地1m处的树干上,开机振动5次(每次振动30s,振动间隔5—10min),可将高大树上的幼虫振落坠地,平均振落率达85.4％,最高可达94.8％。尤其晴天中午,幼虫在取食针叶时最易振落、效果最佳。以振落率为参数可准确推算高大树上的幼虫数量。应用振动机调查高大树上害虫数量,可就地作业、随即统计,具有简捷直观、准确可靠等优点。可在生产实践中广泛推广应用。
The amount of pests on high trees is very difficult to be detected accurately. Thus the accuracy of prediction and forecast of the pests will be greatly affected by this reason. A vibrator which was developed by the forest Machinery Research Section of Nanjing Forestry Univesity was used to detect the amount and instars of the pine caterpillar of the overwintering generation in 1989. The height of the tested pine trees are from 5.0 to 10.2 meter and the diameter of them are from 15.0 to 25.0 centimeter. The vibrator mounted on the trunk was about 1.0 meter above the ground. After starting the vibrator, the trees were vibrated 5 times, each vibration lasted 30 seconds. and the interval between two vibrations was 5-10 minites. The average vibration fall rate of the pests was 85.4％ with the highest rate up to 94.8％. The pests were easily to fell by vibration at the middle of fine days when the caterpillar were eating on the pine needles. The vibration fall rate could be used to calculate accurately the amount of the pine caterpillars on high trees. This method has many metits such as simplicity, accuracy, reliability etc. Hitting trees
5.5-8.7 meters in height, and 13.3-19.7 centimeters in diameter with big stone for 10 times, the vibration fall rates are only 4.7-19.0％; and the method of calculating the larval amount by feces, is more complex and time-consuming than this method. In laboratory the frequency of the best effect was 20-30 Hz; starting instantaneous electrical current was 0.31 A; vibrating acceleration was 11.5 g.
出处
《林业科学》
EI
CAS
CSCD
北大核心
1991年第6期595-601,共7页
Scientia Silvae Sinicae
