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51.
Simon Lüderwald Kymberly Newton Katharina Heye Kristina Bitter Samuel Moeris Lena Benner Paul Böhm Josef Koch Alexander Feckler Mafalda Castro Andreas Erikkson 《Environmental Sciences Europe》2018,30(1):41
This commentary is an introduction for students to the Society of Environmental Toxicology and Chemistry (SETAC) and its Student Advisory Council (SAC). As young academics face challenges while trying to develop their careers, SETAC and the SAC help facilitate student involvement in the various communities within the society that can help to develop the students’ careers within the environmental sciences [e.g. the German Language Branch (GLB)]. This piece would also like to emphasize and pay homage to the continual cooperation between the SAC and the ESEU, which provides a scientific platform to communicate internationally and beyond the borders of SETAC, as well as offer heartfelt congratulations from the SAC to the GLB for their “20 Years SETAC GLB” and deep gratitude for their strong advocacy and support of the SAC. 相似文献
52.
Gerba Leta Girma Kelboro Till Stellmacher Kristof Van Assche Anna‐Katharina Hornidge 《Natural resources forum》2018,42(2):93-107
A public mobilization approach known as nikinake drives implementation and technology upscaling in Ethiopia's agricultural extension. This study investigates and describes the processes and effectiveness of nikinake as an extension method used for natural resource management (NRM). The paper draws on empirical field research conducted in Oromia and the southern region of Ethiopia by looking at nikinake in the context of a watershed management campaign in 2015 and 2016. Nikinake is used as an approach to mobilize the public and to promote the skills of farmers and development actors. In principle, the implementation of NRM is voluntary; however, it is largely planned top‐down and enforced through state actors and informal institutions. This study suggests effective integration of social mobilization with reliable extension and a paradigm shift in emphasis from spatial coverage to an effective outcome. Additionally, sustainability and scalability of NRM interventions could be ameliorated by improving experts’ technical skills, raising farmers’ awareness, improving an incentive system, building trust, and better integrating past watershed management and future planning activities. We reflect on the significance of the nikinake experience in Ethiopia for a broader theory of extension‐as‐mobilization for rural development. From the Ethiopian case, a more general recommendation emerges for extension‐as‐mobilization schemes. For long‐term development, it is worthwhile to consider the fit between yearly campaigns as ad hoc project organizations and the existing pattern of actors and institutions responsible for rural development. 相似文献
53.
Katharina?FoersterEmail author Bart?Kempenaers 《Behavioral ecology and sociobiology》2004,56(5):482-490
In temperate passerines, increased testosterone (T) levels during breeding mediate male aggressive and mating behaviour. If individual variability in T levels is reflected in behavioural differences during mating, males with higher T might gain higher reproductive success. This can be tested experimentally by elevating T levels. However, high exogenous T levels are known to have negative effects on male sperm production. This may reduce male fitness, particularly if sperm competition is intense. We experimentally elevated T levels in breeding blue tit males to investigate how T levels above the natural mean influence male reproductive success. Contrary to most—if not all—previous experimental manipulations of T levels in birds, we restricted the treatment with exogenous T to the time when females were fertile and T levels were naturally high in males. In blue tits, extra-pair paternity is an important component of male reproductive success, and its frequency is likely influenced by androgen-mediated behaviours such as mate attraction and aggression towards other males. Here we show that T-males were equally likely to become cuckolded and did not gain more extra-pair paternity than control males. Cuckolded T-males, however, lost more paternity than control males. We discuss the possibility that this is caused by negative effects of T treatment on sperm production.Communicated by M. Webster 相似文献
54.
Silvio Schueler Katharina Heinke Schlünzen 《Environmental Modeling and Assessment》2006,11(3):179-194
We present the extension and application of the mesoscale atmospheric meteorology model METRAS for dispersion of oak pollen.
We incorporated functions for pollen emission, pollen viability and pollen deposition into METRAS and simulated pollen dispersal
on a scale of up to 200 km. The basis of the simulations is a real landscape structure that includes topography, land use,
and the location and size of oak stands. We simulated the oak pollen dispersion of one single oak stand with an estimated
annual pollen production of 1 billion pollen grains/m2 forest surface on two exemplary days of the flowering season in 2000. Depending on the meteorological situation of the simulated
days, a pollen cloud with about 10 pollen/m3 may extend up to 30 km from the source. Downstream of the oak stand, approximately 1,000 pollen/m2 deposited up to a distance of 25 km, and lower amounts of pollen deposited up to 100 km away. These values of pollen concentration
and deposition lay within the range of published field studies. Overall, it is shown that mesoscale atmospheric models are
applicable to simulate pollen dispersal on the landscape level. 相似文献
55.
56.
Mooshammer M Wanek W Schnecker J Wild B Leitner S Hofhansl F Blöchl A Hämmerle I Frank AH Fuchslueger L Keiblinger KM Zechmeister-Boltenstern S Richter A 《Ecology》2012,93(4):770-782
Resource stoichiometry (C:N:P) is an important determinant of litter decomposition. However, the effect of elemental stoichiometry on the gross rates of microbial N and P cycling processes during litter decomposition is unknown. In a mesocosm experiment, beech (Fagus sylvatica L.) litter with natural differences in elemental stoichiometry (C:N:P) was incubated under constant environmental conditions. After three and six months, we measured various aspects of nitrogen and phosphorus cycling. We found that gross protein depolymerization, N mineralization (ammonification), and nitrification rates were negatively related to litter C:N. Rates of P mineralization were negatively correlated with litter C:P. The negative correlations with litter C:N were stronger for inorganic N cycling processes than for gross protein depolymerization, indicating that the effect of resource stoichiometry on intracellular processes was stronger than on processes catalyzed by extracellular enzymes. Consistent with this, extracellular protein depolymerization was mainly limited by substrate availability and less so by the amount of protease. Strong positive correlations between the interconnected N and P pools and the respective production and consumption processes pointed to feed-forward control of microbial litter N and P cycling. A negative relationship between litter C:N and phosphatase activity (and between litter C:P and protease activity) demonstrated that microbes tended to allocate carbon and nutrients in ample supply into the production of extracellular enzymes to mine for the nutrient that is more limiting. Overall, the study demonstrated a strong effect of litter stoichiometry (C:N:P) on gross processes of microbial N and P cycling in decomposing litter; mineralization of N and P were tightly coupled to assist in maintaining cellular homeostasis of litter microbial communities. 相似文献
57.
Symbiont specificity and bleaching susceptibility among soft corals in the 1998 Great Barrier Reef mass coral bleaching event 总被引:1,自引:0,他引:1
Considerable variability in bleaching was observed within and among soft coral taxa in the order Alcyonacea (Octocorallia:
Cnidaria) on the central Great Barrier Reef (GBR, latitude 18.2°–19.0°S, longitude 146.4°–147.3°E) during the 1998 mass coral
bleaching event. In April 1998, during a period of high sea surface temperatures, tissue samples were taken from bleached
and unbleached colonies representative of 17 soft coral genera. The genetic identities of intracellular dinoflagellates (Symbiodinium spp.) in these samples were analyzed using PCR-denaturing gradient gel electrophoresis fingerprinting analysis of the internal
transcribed spacer regions 1 and 2. Alcyonaceans from the GBR exhibited a high level of symbiont specificity for Symbiodinium types mostly in clade C. A rare clade D type (D3) was associated only with Clavularia koellikeri, while Nephthea sp. hosted symbionts in clade B (B1n and B36). Homogenous Symbiodinium clade populations were detected in all but one colony. Colonies that appeared bleached possessed symbiont types that were
genetically indistinguishable from those in nonbleached conspecifics. These data suggest that parameters other than the resident
endosymbionts such as host identity and colony acclimatization are important in determining bleaching susceptibility among
soft corals.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
58.
Katharina?BielyEmail author Dries?Maes Steven?Van?Passel 《Environment, Development and Sustainability》2018,20(1):223-232
Since the introduction of the sustainability challenge, scientists disagree over the interpretation of the term “sustainability.” Weak and strong sustainability are the two main interpretations of sustainability, which are opposing each other. Some researchers stated that the interpretation of the term depends on the context; others disagree pointing out that it always implies the meaning of continuation. The term “sustainability” can be used as attribute, which adds a certain characteristic to the noun. If something can be attributed as being sustainable, it can also be unsustainable. The sustainability challenge consists of shifting from the current unsustainable towards a sustainable system. This paper outlines that the weak sustainability term is illegitimate, as it leads to a contradiction with the acknowledged assumption that the current state is unsustainable. This contradiction is revealed through an analysis of the occurrence of decoupling in agriculture: Agricultural land use could be decoupled from agricultural production, but only with the trade-off of massive increases in fertilizer, pesticide, energy and water usage. This paper outlines an inherent inconsistency within the ongoing discussion about the interpretation of sustainability. Through identifying the invalidity of the weak sustainability interpretation the focus can be shifted form the discourse to the sustainability challenge itself. 相似文献
59.
Göpel Jan Schüngel Jan Schaldach Rüdiger Meurer Katharina H. E. Jungkunst Hermann F. Franko Uwe Boy Jens Strey Robert Strey Simone Guggenberger Georg Hampf Anna Parker Phillip 《Regional Environmental Change》2018,18(1):129-142
Regional Environmental Change - The calculation of robust estimates of future greenhouse gas emissions due to agriculture is essential to support the framing of the Brazilian climate change... 相似文献
60.
Issues of connectivity between different infrastructure sectors have received surprisingly little attention in recent research. Despite huge interest in issues of sectoral integration surrounding the water–energy nexus, researchers have rarely considered what this might mean for the coupling of infrastructure systems for water/wastewater and energy services. Consequently, the implications of greater connectivity for the governance and socio-spatial constitution of infrastructures are largely unexplored. This paper addresses this research gap with a case study of an attempt to use treated wastewater to produce biomass for energy on degraded land in the Berlin–Brandenburg region of Germany. It takes water reuse for energy crop production as an exemplar of work at the water–energy nexus in order to explore the institutional, spatial and physical dimensions involved in connecting two infrastructure systems to this end. It argues that cross-sectoral integration reaches far beyond issues of technological compatibility, revealing often hidden but crucial differences in the institutional and spatial configuration of energy and wastewater systems. The paper draws conclusions on the broader implications of the case for understanding institutional challenges of cross-sectoral connectivity on the one hand and prospects for reconfiguring infrastructural relations between cities and rural areas on the other. 相似文献