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171.
Landscape services: the concept and its practical relevance 总被引:1,自引:1,他引:0
Olaf Bastian Karsten Grunewald Ralf-Uwe Syrbe Ulrich Walz Wolfgang Wende 《Landscape Ecology》2014,29(9):1463-1479
Recently, in addition to the popular concept of “ecosystem services” (ES), the term “landscape services” (LS) has come into use. We are examining the question of whether a stronger focus on LS would be useful, particularly with regard to case studies carried out in Germany. Important reasons for introducing the term LS include the prominent role of spatial aspects, the reference to landscape elements and the landscape character, and the relevance of LS for landscape planning. We found no strong arguments for replacing the concept of ES by LS; however, we do prefer a situation-related use of both concepts. We propose the following definition: Landscape services are the contributions of landscapes and landscape elements to human well-being. 相似文献
172.
173.
Susanne Kramer Sven Marhan Liliane Ruess Wolfgang Armbruster Olaf Butenschoen Heike Haslwimmer Yakov Kuzyakov Johanna Pausch Nicole Scheunemann Jochen Schoene Andreas Schmalwasser Kai Uwe Totsche Frank Walker Stefan Scheu Ellen Kandeler 《Pedobiologia》2012,55(2):111-119
The origin and quantity of plant inputs to soil are primary factors controlling the size and structure of the soil microbial community. The present study aimed to elucidate and quantify the carbon (C) flow from both root and shoot litter residues into soil organic, extractable, microbial and fungal C pools. Using the shift in C stable isotope values associated with replacing C3 by C4 plants we followed root- vs. shoot litter-derived C resources into different soil C pools. We established the following treatments: Corn Maize (CM), Fodder Maize (FM), Wheat + maize Litter (WL) and Wheat (W) as reference. The Corn Maize treatment provided root- as well as shoot litter-derived C (without corn cobs) whereas Fodder Maize (FM) provided only root-derived C (aboveground shoot material was removed). Maize shoot litter was applied on the Wheat + maize Litter (WL) plots to trace the incorporation of C4 litter C into soil microorganisms. Soil samples were taken three times per year (summer, autumn, winter) over two growing seasons. Maize-derived C signal was detectable after three to six months in the following pools: soil organic C (Corg), extractable organic C (EOC), microbial biomass (Cmic) and fungal biomass (ergosterol). In spite of the lower amounts of root- than of shoot litter-derived C inputs, similar amounts were incorporated into each of the C pools in the FM and WL treatments, indicating greater importance of the root- than shoot litter-derived resources for the soil microorganisms as a basis for the belowground food web. In the CM plots twice as much maize-derived C was incorporated into the pools. After two years, maize-derived C in the CM treatment contributed 14.1, 24.7, 46.6 and 76.2% to Corg, EOC, Cmic and ergosterol pools, respectively. Fungi incorporated maize-derived C to a greater extent than did total soil microbial biomass. 相似文献
174.
Deres K Schröder CH Paessens A Goldmann S Hacker HJ Weber O Krämer T Niewöhner U Pleiss U Stoltefuss J Graef E Koletzki D Masantschek RN Reimann A Jaeger R Gross R Beckermann B Schlemmer KH Haebich D Rübsamen-Waigmann H 《Science (New York, N.Y.)》2003,299(5608):893-896
Chronic hepatitis B virus (HBV) infection is a major cause of liver disease. Only interferon-alpha and the nucleosidic inhibitors of the viral polymerase, 3TC and adefovir, are approved for therapy. However, these therapies are limited by the side effects of interferon and the substantial resistance of the virus to nucleosidic inhibitors. Potent new antiviral compounds suitable for monotherapy or combination therapy are highly desired. We describe non-nucleosidic inhibitors of HBV nucleocapsid maturation that possess in vitro and in vivo antiviral activity. These inhibitors have potential for future therapeutic regimens to combat chronic HBV infection. 相似文献
175.
A PINOID-dependent binary switch in apical-basal PIN polar targeting directs auxin efflux 总被引:1,自引:0,他引:1
Friml J Yang X Michniewicz M Weijers D Quint A Tietz O Benjamins R Ouwerkerk PB Ljung K Sandberg G Hooykaas PJ Palme K Offringa R 《Science (New York, N.Y.)》2004,306(5697):862-865
Polar transport-dependent local accumulation of auxin provides positional cues for multiple plant patterning processes. This directional auxin flow depends on the polar subcellular localization of the PIN auxin efflux regulators. Overexpression of the PINOID protein kinase induces a basal-to-apical shift in PIN localization, resulting in the loss of auxin gradients and strong defects in embryo and seedling roots. Conversely, pid loss of function induces an apical-to-basal shift in PIN1 polar targeting at the inflorescence apex, accompanied by defective organogenesis. Our results show that a PINOID-dependent binary switch controls PIN polarity and mediates changes in auxin flow to create local gradients for patterning processes. 相似文献