PDF《早竹林内蝇类多样性动态及其影响因子分析*》

52 卷were analyzed using the multiple linear regression. In addition, the method of variation partitioning was employed to analyze the β diversity caused by environmental and spatial variables. [Results] Ten species of flies from

8 families were identified in P. violascens stands in the Dajingshan forest farm, among which Chyliza bambusae, Pegomyia kiangsuensis, Anthomyia illocata, Hydrotaea dentipes and Episyrphus balteata were the dominant species. The number of adult bamboos and that of young bamboo shoots within a radius of 1.5 m around yellow sticky traps had a significant influence on the species diversity of flies;

diversity declined with increasing number of adult bamboos. Total variation of the species matrix can be partitioned as follows: spatial species variation not shared by the environmental variables comprised, 8.54%, non-spatial environmental variation, 28.84%, spatially structured environmental variation, 10.46%, and unexplained variation and stochastic fluctuations, 52.16%. [Conclusion] This study revealed the temporal dynamics of flies in P. violascens stands and illustrated the main factors affecting the species diversity of flies. These results have both practical and theoretical implications for increasing the production of bamboo shoots and also for the integrated management of the insect pests of bamboo. Key words β diversity, Shannon-Wiener index, spatial variable, environmental variable, variation partitioning 早竹 Phyllostachys violascens 又名雷竹,为 禾本科竹亚科刚竹属植物, 是一种优良的笋用竹 种,具有出笋早、笋期长、产量高、无明显大小 年等特点,主要分布在长江以南的浙江、江苏、 安徽、江西等省,以德清、余杭和临安三县(市) 及杭州市郊为盛.早竹既是生态竹种,又是成本 低、效益好的经济竹种,早竹笋具有低糖、低脂 等特点,口感鲜嫩香脆,备受人们的青睐.自1995 年从浙江引种栽培早竹以来,经过近

20 年 的发展, 早竹笋产业已成为高淳县农业的龙头产 业.该县早竹主要以专业户承包经营为主,承包 户多以家庭模式经营,每户承包规模 1.33~2.00 hm2 .由于早竹笋在前期产量少价格高,所以采 用覆盖以提早出笋的技术在高淳县被广泛采用. 据统计,使用覆盖技术的早竹林每

667 m2 的纯 收入为

8 000~15

000 元,而不使用覆盖技术的 早竹林其每亩纯收入只有

2 000~3

000 元. 由于 覆盖一般采用稻草、 砻糠和有机肥等容易滋生蝇 类,早竹园受蝇类危害严重,退笋率增加、竹笋 品质下降,给当地农民带来了较大的经济损失. 据我们初步调查,由于蝇类的寄生,早竹笋退笋 ........