Effects Of Different Agricultural Landscape Patterns To Moth Insects Biodiversity Under The Lamp In Southern Xinjiang

It has become a research hot spot to assess pest population dynamics and habitat management from the landscape scale in the field of regional scale integrated pest management.The typical oases in the Tarim Basin were selected as research geographical units,Combined with Google earth map, GPS was used to investigate the agricultural landscape structure in a2km radius around the light and to study the effects of crop landscape on thepopulation dynamics of moth insects under the lamps.At the same time,the frequency trembler grid lamp was used to study the population dynamics of moth insects.Exploring the population dynamics of moths among the different farmland landscape structure and the different proportion of cotton structure.The results showed as follows:1.10338individuals and120species were collected during during the trial,including11families of Lepidoptera, such as Noctuidae, Pyralidae, Sphingidae, Geometridae and so on;Thenumber dominant species of the different families were larger differences,and the species and thenumbers of the Noctuidae were most.Statistics analysis was indicated that the trend of the changeswith date in the diversity index（H’） is coincident with that of evenness index（J’）,the index washighest in middle of July and August; The dominance index（C）was higher in middle of June；The richness index（E）was higher at the beginning of June，then dropped to the low level,itschanges were poised.The model of moth species abundance distribution indicated that the habitatof farmland was fine.2. The different agricultural landscapes such as Complex landscape A: complicated cropstructure with a large proportion of greenhouses; Complex landscape B: complicated cropstructure; Simple landscape: single crop structure with a large-scale.The landscape diversityindexes of the two kinds of complex agricultural landscapes were both significantly higher thanthat of the simple landscape;The species of moth insects under complicated landscape B werehigher than the others,and those in simple landscape was higher than that in complex landscapeA.At the beginning of the test, the number of the moths in complex landscape B were higher thanthe others;The index of diversity of different landscape was different,cmplex landscape of the bothhad the same varying trend;The richness index of the complex landscape were higher than that ofsimple landscape.3. Different species of cutworms had different responses to three types of landscapes，therewere no significant differences between the population numbers of Agrotis segetam in differenttypes of landscapes, the population numbers of Amathes c-nigrum and Agrotis exclamationis ofcomplex landscape B were dramatically higher than those of complex landscape A and simplelandscape,the difference were significant;The correlation between the different landscape factorsand the population numbers of cutworms were distinct; the population growth rate of cutworms ofthe complicated landscape B was higher than others. Complex agricultural landscape had bufferfunction to the pest population dynamics which disturbed by human intervention,whosepopulation dynamics of pests had no large fluctuations compared with the simple landscape.4. Larval host types for the cutworms in South Xinjiang determined by δ¹³C in mothwings. Our results showed that the host corps of Amathes c-nigrum were almost entirely from C₃photosynthetic plants such as corn cultivars, wheat et.al in different agriculturallandscapes;This may cause serious loses in C3photosynthetic crops.5. Different proportion of cotton crop system,the species and populations in the25%proportion were most,the diversity index and richness index changed outer-plane changes overtime;The diversity index of50%proportion of cotton crop descended with the time,on thecontrary,the richness index rised with the passage of time;But the diversity index and richnessindex remained stable in the75%proportion of cotton crop,the total number of moth insects wasless.