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Breeding birds in field boundaries in an agricultural landscape.
1996
Sparks T.H. | Parish T. | Hinsley S.A.
Effects of an invading coccinellid on native coccinellids in an agricultural landscape Texte intégral
1996
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.
Afficher plus [+] Moins [-]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))
Measuring biodiversity at ecosystem level in an agricultural landscape Texte intégral
2002 | 1996
Alanen, Aulikki | Rekolainen, Seppo | Siitonen, Mikko | Tiainen, Juha | Pakkala, Timo | Bäckman, Jan-Peter | Helenius, Juha | Ruuska, Riitta | Hietala-Koivu, Reija | Suomen Ympäristökeskus | Suomen Ympäristökeskus | Suomen ympäristökeskus | Riista- ja kalatalouden tutkimuslaitos | Helsingin yliopisto | Helsingin yliopisto | Helsingin yliopisto, Kasvintuotantotieteen laitos | Helsingin yliopisto, Kasvintuotantotieteen laitos | Maatalouden tutkimuskeskus (MTT) / YTL Ympäristöntutkimuslaitos / Ympäristöntutkimuslaitos YTL
v | ok | Reija Hietala-Koivu
Afficher plus [+] Moins [-][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
Afficher plus [+] Moins [-]Sediment transport in an agricultural field. Processes and budget. Texte intégral
1996
Cros-Cayot, S. | Gascuel-Odoux, C.
Macrocharacterization of agricultural systems in Central Africa: an overview
1996
Manyong, Victor M. | Smith, J. | Weber, S.S. | Jagtap, S.S. | Oyewole, B.
Forest floor spiders of woodlots in an agricultural landscape
1996
Mabelis, A.
GIS analysis of change in an agricultural landscape in Central Finland Texte intégral
1996
Ruuska, Riitta | Helenius, Juha
GIS analysis of change in an agricultural landscape in Central Finland
1996
Ruuska, Riitta | Helenius, Juha
GIS analysis of change in an agricultural landscape in Central Finland Texte intégral
2002 | 1999 | 1996
Ruuska, Riitta | Helenius, Juha
v | ok | Keskisuomalaisen maatalousmaiseman muutosten GIS-analyysi
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