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Seven native coccinellid species inhabited alfalfa, corn, and small grain fields in eastern South Dakota prior to invasion and establishment of Coccinella septempunctata L. Six species occurred in all crops, however, Adalia bipunctata (L.) occurred only in corn. The structure of native coccinellid communities differed significantly for years prior to compared with years after establishment of C. septempunctata in fields of the three agricultural crops. Differences in community structure were accounted for mainly by reduced abundance of two species, C. transversoguttata richardsoni Brown and Adalia bipunctata (L.). Annual abundance of C. transversoguttata richardsoni averaged 20-32 times lower during post-invasion years than in years prior to invasion, depending on crop; while annual abundance of A. bipunctata averaged 20 times lower in corn after invasion. Addition of C. septempunctata to the community did not result in a significant increase in total abundance of coccinellids in the crops. Coccinellid abundance in agricultural crops may be limited by the total abundance of prey or by the availability of other requisites in the landscape as a whole. Therefore, introduction of a new species, while resulting in reductions in native species populations, may not increase total coccinellid abundance, and may therefore have no net effect on biological control of aphid pests.

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interspecific competition indigenous species communities field crops species diversity medicago sativa small grain crops species abundance ...

National Agricultural Library - United States of America

Effects of an invading coccinellid on native coccinellids in an agricultural landscape

1996

Elliott, N. | Kieckhefer, R. | Kauffman, W. (USDA, ARS, SPA Plant Science Research Laboratory, Stillwater, OK (USA))

lutte biologique host parasite relations biological competition aphididae biological control coccinellidae relation hote parasite relaciones huesped parasito competencia biologica relation predateur proie relaciones predator presa control biologico ...

ZB MED Nutrition. Environment. Agriculture - Germany

Measuring biodiversity at ecosystem level in an agricultural landscape 全文

2002 | 1996

v | ok | Reija Hietala-Koivu

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luonnon monimuotoisuus ekosysteemit maisema maisemanhoito biodiversiteetti ys

Natural Resources Institute Finland - Finland

[Geographic Information System: an approach in agricultural technology extrapolation]

1996

Arifin, Z. (Balai Pengkajian Teknologi Pertanian Karangploso, Malang (Indonesia))

Geographical Information System (GIS) is an art media through a computer technology by displaying a map in a digital form which is achieved from the combination of geographical and agricultural data. Combination and interpretation result of these data can be extrapolated into such a domain with same agroecosystem. The application of the specific location technology are based on the resume and selection of the experimental result and in confirmity with the existing new information and data development. The output of the extrapolation within GIS is a useful decision for farmer, extension people, researcher, and the decision maker. The map can anticipate the come up problem immediately and may gives another important information based on specific agroecosystem | Sistem Informasi Geografi (SIG) merupakan media seni melalui teknologi komputer dengan memperagakan peta dalam bentuk digital yang diperoleh melalui penggabungan data geografi dan data pertanian. Dari hasil penggabungan dan penjabaran data tersebut dapat diekstrapolasikan pada suatu wilayah dengan agroekosistem sama. Penerapan teknologi spesifik lokasi didasarkan pada rangkuman dan seleksi hasil-hasil penelitian dan disesuaikan dengan perkembangan informasi atau data baru yang ada. Output ekstrapolasi dalam SIG berupa suatu keputusan yang sangat berguna bagi petani, penyuluh, peneliti, dan pembuat kebijakan. Dengan peta tersebut dapat menjawab secara cepat permasalahan yang ada serta dapat memberikan informasi penting lainnya berdasarkan agroekosistem spesifik

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geographie geography geografia information systems remote sensing sistemas de informacion teledeteccion systeme d'information teledetection

Indonesian Center for Agricultural Library and Technology Dissemination - Indonesia