Braunschweig, Germany
Braunschweig, Germany

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Marquard E.,Helmholtz Center for Environmental Research | Dauber J.,Thunen Institute For Biodiversitat | Doerpinghaus A.,Bundesamt fur Naturschutz Referat Planung | Droschmeister R.,Bundesamt fur Naturschutz | And 13 more authors.
Natur und Landschaft | Year: 2013

In the light of rapid global change and the impending loss of ecosystem services, informative data on the state and trends of biological diversity are vital. Generating these data in Germany requires modifications to and better coordination among the existing monitoring programmes. To this end, closer cooperation between scientific institutions, executing agencies and other relevant organizations is needed. The following recommendations summarize the authors' views on aspects key to reshaping the biological monitoring programmes in Germany:.

Neumann D.,Thunen Institute For Biodiversitat | Neumann D.,Helmholtz Center Potsdam | Heuer A.,Thunen Institute For Biodiversitat | Hemkemeyer M.,Thunen Institute For Biodiversitat | And 2 more authors.
FEMS Microbiology Ecology | Year: 2013

The objective of this study was to characterize the microbial communities attached to clay (< 2 μm), fine silt (2-20 μm), coarse silt (20-63 μm) and sand-sized fractions [> 63 μm; including particulate organic matter (POM)] of an arable soil and analyse their response to more than 100 years of two different fertilization regimes. Mild ultrasonic dispersal, wet-sieving and centrifugation allowed the separation of soil particles with the majority of bacterial cells and DNA still attached. Fertilizations increased soil organic carbon (SOC), total DNA and the abundance of bacterial, archaeal and fungal rRNA genes more strongly in the larger-sized fractions than in fine silt, and no effect was seen with clay, the latter representing above 70% of the total microbial populations. A highly positive correlation was found between microbial rRNA genes and the surface area provided by the particles, while the correlation with SOC was lower, indicating a particle-size-specific heterogeneous effect of SOC. The prokaryotic diversity responded more strongly to fertilization in the larger particles but not with clay. Overall, these results demonstrate that microbial responsiveness to long-term fertilization declined with smaller particle sizes and that especially clay fractions exhibit a high buffering capacity protecting microbial cells against changes even after 100 years under different agricultural management. © 2013 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Valldor P.,Thunen Institute For Biodiversitat | Miethling-Graff R.,Thunen Institute For Biodiversitat | Martens R.,Thunen Institute For Biodiversitat | Tebbe C.C.,Thunen Institute For Biodiversitat
Applied Microbiology and Biotechnology | Year: 2015

Insecticidal delta-endotoxins of Bacillus thuringiensis are among the most abundant recombinant proteins released by genetically modified (GM) crops into agricultural soils worldwide. However, there is still controversy about their degradation and accumulation in soils. In this study, 14C-labelled Cry1Ab protein was applied to soil microcosms at two concentrations (14 and 50 μg g−1 soil) to quantify the mineralization of Cry1Ab, its incorporation into the soil microbial biomass, and its persistence in two soils which strongly differed in their texture but not in silt or pH. Furthermore, ELISA was used to quantify Cry1Ab and its potential immunoreactive breakdown products in aqueous soil extracts. In both soils, 14CO2-production was initially very high and then declined during a total monitoring period of up to 135 days. A total of 16 to 23 % of the 14C activity was incorporated after 29 to 37 days into the soil microbial biomass, indicating that Cry1Ab protein was utilized by microorganisms as a growth substrate. Adsorption in the clay-rich soil was the most important factor limiting microbial degradation; as indicated by higher degradation rates in the more sandy soil, extremely low concentrations of immunoreactive Cry1Ab molecules in the soils’ aqueous extracts and a higher amount of 14C activity bound to the soil with more clay. Ecological risk assessments of Bt-crops should therefore consider that the very low concentrations of extractable Cry1Ab do not reflect the actual elimination of the protein from soils but that, on the other hand, desorbed proteins mineralize quickly due to efficient microbial degradation. © 2015, Springer-Verlag Berlin Heidelberg.

The biodiversity of agricultural landscapes is declining. We have consolidated knowledge about the state and development of biodiversity on agricultural land and about the drivers of biodiversity change. Our knowledge is based on monitoring as well as on regional case studies. Nevertheless, we have to question whether the database is sufficient today and in the long term to inform policy-makers when drafting efficient measures for agricultural landscapes. We see an urgent need to collate the available data in analyses that are designed to derive efficient measures adapted to regional characteristics and differentiated agrarian structures. National-scale monitoring, supported by regional case studies, should be further expanded in order to assess the existing instruments of the European Common Agricultural Policy (CAP) and inform policy about future responses needed. To this end, scientific concepts must be developed and the relevant databases should be released for use by science.

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