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新疆北部粮棉混作生态区天敌群落转移规律的初步研究 被引量:4
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作者 郭文超 许建军 +1 位作者 何江 白山.哈吉泰 《新疆农业科学》 CAS CSCD 2000年第z1期119-122,共4页
1997~ 1999年通过对新疆玛纳斯县粮棉混作生态区天敌的群落转移及数量变动规律的系统调查 ,初步摸清了新疆北部粮棉混作区天敌群落的组成及优势种天敌、以及天敌与害虫发生之间的关系 ,结果表明 ,北疆粮棉混作区天敌群落以捕食性天敌为... 1997~ 1999年通过对新疆玛纳斯县粮棉混作生态区天敌的群落转移及数量变动规律的系统调查 ,初步摸清了新疆北部粮棉混作区天敌群落的组成及优势种天敌、以及天敌与害虫发生之间的关系 ,结果表明 ,北疆粮棉混作区天敌群落以捕食性天敌为主 ,天敌种类主要有蜘蛛类、捕食甲类、食虫蝽类、草蛉类、瓢虫类、寄生蜂类、食蚜蝇类等。春季 4月上旬至 5月上旬越冬后天敌主要分布于麦田 ,少量分布于林带、果园及田埂渠道上早发的多年生杂草上 ,如田旋花及禾本科杂草早熟禾等。 5月下旬麦田天敌大量向棉田、玉米田转移 ,在棉田经大量繁殖后 ,于 7月上旬达到高峰 ,7月中、下旬逐渐外迁至多年生果园、复播作物、杂草、林带准备越冬 ,9月下旬至 10月上旬冬麦出苗后 ,部分天敌迁入冬麦田越冬。 展开更多
关键词 粮棉混作生态天敌群落转移规律
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美国的“生物圈2号”
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《资料卡片杂志》 2003年第5期44-45,共2页
关键词 美国 “生物圈2号”计划 外星球 生态系统 物种平衡 生态群落区
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Co-occurrence Patterns of Above-ground and Below-ground Mite Communities in Farmland of Sanjiang Plain, Northeast China 被引量:7
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作者 LIN Lin GAO Meixiang +3 位作者 LIU Dong ZHANG Xueping WU Haitao WU Donghui 《Chinese Geographical Science》 SCIE CSCD 2014年第3期339-347,共9页
One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, litt... One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, little is known with regard to co-occurrence patterns in above-ground and below-ground communities. In this paper, we used a null model to test non-randomness in the structure of the above-ground and below-ground mite communities in farmland of the Sanjiang Plain, Northeast China. Then, we used four tests for non-randomness to recognize species pairs that would be demonstrated as significantly aggregated or segregated co-occurrences of the above-ground and below-ground mite communities. The pattern of the above-ground mite commu- nity was significantly non-random in October, suggesting species segregation and hence interspecific competition. Additionally, species co-occurrence patterns did not differ from randomness in the above-ground mite community in August or in below-ground mite com- munities in August and October. Only one significant species pair was detected in the above-ground mite community in August, while no significant species pairs were recognized in the above-ground mite community in October or in the below-ground mite communities in August and October. The results indicate that non-randomness and significant species pairs may not be the general rule in the above-ground and below-ground mite communities in farmland of the Sanjiang Plain at the fine scale. 展开更多
关键词 above-ground mite below-ground mite mite communities co-occurrence patterns interspecific competition species pairassociations
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Understory flora and community physiognomy of planted forests in the degraded purple soil ecosystem, South China 被引量:1
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作者 YUZhan-yuan YUEYong-jie +4 位作者 GUOJian-fen CHENGuang-shui XIEJin-sheng HEZong-ming YANGYu-sheng 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第2期109-112,共4页
The flora and community physiognomy of degraded plantation ecosystems onpurple soil were investigated in Ninghua County of Fujian Province, China to understand therelationship between plant diversity and ecosystem pro... The flora and community physiognomy of degraded plantation ecosystems onpurple soil were investigated in Ninghua County of Fujian Province, China to understand therelationship between plant diversity and ecosystem processes.. Four different restorationcommunities (labeled as ecological restoration treatment Ⅰ, Ⅱ, Ⅲ and Ⅳ) were selected byspace-time replacement method according to the erosion intensity in degraded purple soil ecosystem.The results showed that there were totally 86 plant species belonging to 78 genera and 43 familiesin the degraded purple soil ecosystem. Of the 15 types of distribution area in spermatophyte genus,12 types were found in the purple soil ecosystem. Along restoration gradient from low to high, plantgrowth type and life form spectra became abundant more and more, and the spermatophyte genera foreach distribution area type and genera numbers for different foliage characters increased as well.It is concluded that the plant flora and physiognomy in ecological restoration process become morecomplex and diverse, indicating that the forest ecosystem on purple soil tends to be more stable. 展开更多
关键词 purple soil FLORA community physiognomy BIODIVERSITY ecosystem processes
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Causal Analyses of Desertification in Semi-arid Agro-pastoral Ecotone of China: A Case Study in Ejin Holo County, Inner Mongolia 被引量:1
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作者 MAO Lei YU Chuntang YANG Xiaohui 《Chinese Forestry Science and Technology》 2005年第3期11-21,共11页
Desertification is one of serious problems menacing the global environment and food security, andthe determination of causes of desertification is the basic issue for the coordinate actions to fight against it. InChin... Desertification is one of serious problems menacing the global environment and food security, andthe determination of causes of desertification is the basic issue for the coordinate actions to fight against it. InChina, the most serious desertification occurs in agro-pastoral transition zone. Considering the consistencyof socio-economic factors, Ejin Holo county in Inner Mongolia was selected out to analyze the desertificationcauses in this paper. Results showed that erratically climatic factors provided fragile background and drivingforces for desertification processes, and sand-covered surface and its underlying materials and specificgeomorphologic features have a great contribution to desertification processes as well. Socio-economicdevelopment, especially the traditional land management, the landuse patterns and the increase of livestockand human population were the root causes for desertification occurrence and expansion. 展开更多
关键词 desertification causes biophysical factors socio-economic factors semi-add agro-pastoralecotone
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