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Journal of Soils and Sediments - The successful implementation of a plant protection product depends on its effectiveness against a target species and its safety for the environment. Risk...  相似文献   
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The paper presents a hierarchic system of agro‐environmental classification of regions and landscapes. At the highest level are agro‐climatic regions (AKR). Allocating soil data, these units are broken down to soil‐climatic regions (Boden‐Klima Regionen, BKR). The next level is defined by geological data, topography “typical patterns of land uses”; and results in landscape types (LT). The AKR are used to define the intensification level and the energy surplus of agro production. The BKR allow specific analysis of impacts to environment factors of farm production systems. In the LT, specific targets for sustainable production and landscape rehabilitation are developed. The results are proposals to refine European agro‐policy towards more environmentally oriented schemes. The data is also valid to control the positive environmental effects of farmers adaptation of schemes.  相似文献   
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Journal of Plant Diseases and Protection - Innovative biological pest control of the western corn rootworm (WCR) Diabrotica virgifera virgifera and wireworms Agriotes spp. in maize and potato...  相似文献   
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The parasitoid wasp Pnigalio agraules (Wlk.) is a key natural enemy of the horsechestnut leafminer Cameraria ohridella Deschka and Dimić (Lepidoptera: Gracillariidae). As a basis for mark-release-recapture studies, aimed at investigating the dispersal of this parasitoid in the field, adults of P. agraules were marked using a vertebrate-specific immunoglobulin (IgG). The marker was later detected by double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). The IgG was either applied externally by spraying or internally by feeding an IgG-enriched diet. Different concentrations of the marker were used and the influence of abiotic (climatic conditions, time elapsed between marking and marker examination) and biotic factors (sex and age of the parasitoids) on the detection of the immunomarker was tested. External marking by spraying led to more homogeneous labelling than feeding the marker. Parasitoids labelled with 0.25 mg rabbit IgG per ten individuals contained enough immunomarker to be easily distinguished from unmarked ones. Neither the climatic conditions nor the sex or age of the insects had an influence on the detection of the marker. The IgG remained well detectable during the entire lifespan of the parasitoids, which was not negatively affected by the marking procedure. Serological marking can be used to investigate the dispersal behaviour of beneficial insects within mark-release-recapture studies.  相似文献   
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Resuspension of benthic phosphorus (P) often constitutes a high percentage of the annual P flux in lowland rivers. To study P entrainment at controlled shear velocity (u*) sediment from lowland River Spree of slower flowing (0.1–0.3 m s?1) stretch Kossenblatt (KOB) and of faster flowing (0.5–0.7 m s?1) stretch Freienbrink (FRB) was incubated in a microcosm at incrementally enhanced u* (0.34–1.9 cm s?1). Particle and P entrainment rates as well as the number of particle-associated bacteria of fine-grained mud-like KOB sediment were much higher (16.7 g m?2 h?1, 104.9 mg P m?2 h?1, 15.47 106 cells ml?1) than those (4.3 g m?2 h?1, 2.1 mg P m?2 h?1, 3.06 106 cells ml?1) of coarser sandy FRB sediment. The microcosm used so far in marine research is suited to compare riverine resuspension suggesting the lower u* the more particles are deposited and the more P can be retained (KOB ? FRB). Conversely, correspondingly more and easier particulate P and bacteria can again be remobilised (KOB ? FRB) if u* increases. The general relationship found for u* and the entrainment of particulate P and bacteria as well as their decelerated and selective deposition where bacteria may stay longer in the water implies a temporarily enhanced P bioavailability, turnover and subsequent P transformations.  相似文献   
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