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11.
In Latin America and the Caribbean, river restoration projects are increasing, but many lack strategic planning and monitoring. We tested the applicability of a rapid visual social–ecological stream assessment method for restoration planning, complemented by a citizen survey on perceptions and uses of blue and green infrastructure. We applied the method at three urban streams in Jarabacoa (Dominican Republic) to identify and prioritize preferred areas for nature-based solutions. The method provides spatially explicit information for strategic river restoration planning, and its efficiency makes it suitable for use in data-poor contexts. It identifies well-preserved, moderately altered, and critically impaired areas regarding their hydromorphological and socio-cultural conditions, as well as demands on green and blue infrastructure. The transferability of the method can be improved by defining reference states for assessing the hydromorphology of tropical rivers, refining socio-cultural parameters to better address river services and widespread urban challenges, and balancing trade-offs between ecological and social restoration goals.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01565-3. 相似文献
12.
Alkylphenols (APs), alkylphenol ethoxylates (APEOs), ethoxycarboxylate metabolites (APECs) and bisphenol A were determined in surface water using solid-phase extraction (SPE) followed by triple-quadrupole LC-MS-MS. APs were separated by LC from APECs using an acetonitrile-water-gradient without the addition of any buffer. Nonylphenol ethoxycarboxylates (NPECs) interfere in the detection of nonylphenols (NPs) when using an acidic mobile phase, because they produce the same MS-MS fragment ions (219>133 and 147). 4n-NP shows the characteristic transition 219>106; it is well suited as internal standard. Nonylphenol ethoxylates NPE(n)Os (n=1-17) were analysed separately in a second run by positive ionization using an ammonium acetate mobile phase. Textile industry discharges, the corresponding wastewater treatment plant (WWTP) effluents and the receiving rivers in Belgium and Italy were analysed. Among the substances investigated, NPE1C and NPE2O exhibited the highest concentrations in the water samples, up to 4.5 microg l(-1) NPE1C in a WWTP effluent and 3.6 microg l(-1) NPE2O in a river. The highest NP levels were found in the receiving rivers (max. 2.5 microg l(-1)). The predicted no-effect concentration (PNEC) for NP of 0.33 microg l(-1) for water species was frequently exceeded in the surface waters investigated, suggesting potential adverse effects to the aquatic environment. 相似文献
13.
Long-term effects of clear-cutting and selective cutting on soil methane fluxes in a temperate spruce forest in southern Germany 总被引:1,自引:0,他引:1
Wu X Brüggemann N Gasche R Papen H Willibald G Butterbach-Bahl K 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2467-2475
Based on multi-year measurements of CH4 exchange in sub-daily resolution we show that clear-cutting of a forest in Southern Germany increased soil temperature and moisture and decreased CH4 uptake. CH4 uptake in the first year after clear-cutting (−4.5 ± 0.2 μg C m−2 h−1) was three times lower than during the pre-harvest period (−14.2 ± 1.3 μg C m−2 h−1). In contrast, selective cutting did not significantly reduce CH4 uptake. Annual mean uptake rates were −1.18 kg C ha−1 yr−1 (spruce control), −1.16 kg C ha−1 yr−1 (selective cut site) and −0.44 kg C ha−1 yr−1 (clear-cut site), respectively. Substantial seasonal and inter-annual variations in CH4 fluxes were observed as a result of significant variability of weather conditions, demonstrating the need for long-term measurements. Our findings imply that a stepwise selective cutting instead of clear-cutting may contribute to mitigating global warming by maintaining a high CH4 uptake capacity of the soil. 相似文献
14.
15.
16.
Sven Rannow Nicholas A. Macgregor Juliane Albrecht Humphrey Q. P. Crick Michael Förster Stefan Heiland Georg Janauer Mike D. Morecroft Marco Neubert Anca Sarbu Jadwiga Sienkiewicz 《Environmental management》2014,54(4):732-743
The implementation of adaptation actions in local conservation management is a new and complex task with multiple facets, influenced by factors differing from site to site. A transdisciplinary perspective is therefore required to identify and implement effective solutions. To address this, the International Conference on Managing Protected Areas under Climate Change brought together international scientists, conservation managers, and decision-makers to discuss current experiences with local adaptation of conservation management. This paper summarizes the main issues for implementing adaptation that emerged from the conference. These include a series of conclusions and recommendations on monitoring, sensitivity assessment, current and future management practices, and legal and policy aspects. A range of spatial and temporal scales must be considered in the implementation of climate-adapted management. The adaptation process must be area-specific and consider the ecosystem and the social and economic conditions within and beyond protected area boundaries. However, a strategic overview is also needed: management at each site should be informed by conservation priorities and likely impacts of climate change at regional or even wider scales. Acting across these levels will be a long and continuous process, requiring coordination with actors outside the “traditional” conservation sector. To achieve this, a range of research, communication, and policy/legal actions is required. We identify a series of important actions that need to be taken at different scales to enable managers of protected sites to adapt successfully to a changing climate. 相似文献
17.
Coupling of 2,4,6-trinitrotoluene (TNT) metabolites onto humic monomers by a new laccase from Trametes modesta 总被引:2,自引:0,他引:2
During degradation of trinitrotoluene (TNT) by Trametes modesta, addition of humic monomers prevented the accumulation of all major stable TNT metabolites (aminodinitrotoluenes [AMDNT]) by at least 92% in the presence of 200 mM ferulic acid and guaiacol. Acute toxicity tests with individual TNT metabolites and in T. modesta cultures supplemented with 200 microM TNT demonstrated that the TNT biodegradation process lead to less toxic metabolites. Toxicity decreased in the order TNT>4-HADNT (4-hydroxylaminodinitrotoluene)>2-HADNT>2,6-DNT (2,6-dinitrotoluene)>2',2',6,6-azoxytetranitrotoluene>4-AMDNT>2-AMDNT>2,4-diamninonitrotoluene (2,4-DAMNT) while 2,4-DNT and 2,6-DAMNT were the least toxic. Ferulic acid is the best candidate for immobilization TNT biodegradation metabolites since it prevented the accumulation of AMDNTs in cultures during TNT biodegradation and its products were less toxic. All humic monomers were very effective in immobilizing 2-HADNT [100%], 4-HADNT [100%] and 2,2,6,6-azoxytetranitrotoluene [100%]. Two distinct laccase isoenzymes (LTM1 and LTM2) potentially involved in immobilization of TNT degradation products were purified to electrophoretic homogeneity. LTM1 and LTM2 have molecular weights of 77.6 and 52.5 kDa, are 18% and 24% glycosylated, have pI values of 3.6 and 4.2, respectively. Both enzymes oxidized all the typical laccase substrates tested. LTM1 showed highest kinetic constants (K(m)=0.03 microM; K(cat)=8.8 4x 10(7)s(-1)) with syringaldazine as substrate. 相似文献
18.
In the presented paper, the pHstat-procedure is compared with four simple extraction procedures. These procedures make use of the following extraction solutions: distilled water (based on DIN 38414 part 4, DIN-S4), 1 mol/L ammonium nitrate, 1 mol/L ammonium acetate at pH 7.0 and 1 mol/L sodium acetate at pH 5.0, respectively. The extraction procedures were applied to 10 different soil samples and 2 sludges. The DIN-S4-procedure shows the lowest amounts of mobilized copper. The highest parts are extracted by sodium acetate solution. For the procedures investigated, the mobilized amounts extracted by ammonium acetate solution are most comparable with those of the pHstat-procedure. The simple sodium acetate procedure is useful for screening to select significant samples from a large number of soils. Thus, the high effort caused by the pHstat-procedure can be reduced to a minimum through the application of this screening procedure. The application of this screening, however, is difficult for samples containing large parts of organic compounds, e.g. sewage sludge. These samples show a different extracting behaviour. 相似文献
19.
Impact of Land Use on Soluble Organic Nitrogen in Soil 总被引:5,自引:0,他引:5
Victoria B. Willett James J. Green Andrew J. Macdonald John A. Baddeley Georg Cadisch Steven M. J. Francis Keith W. T. Goulding Gary Saunders Elizabeth A. Stockdale Christine A. Watson David L. Jones 《Water, Air, & Soil Pollution: Focus》2004,4(6):53-60
Although it has been hypothesized that soluble organic nitrogen (SON) plays a central role in regulating productivity in some terrestrial ecosystems, the factors controlling the size of the SON pool in soil remain poorly understood. Therefore our principal aim in this work was to assess the impact of seven different land use systems (rough and managed grassland, deciduous and coniferous woodland, heathland, wetland and tilled land) on the size of the SON and inorganic N (NO
3
–
, NH
4
+
) pools in the surface soil layer (0–15 cm). After extraction with deionised water, we found that in most cases the size of the water extractable organic N (WEON) pool was similar in size to the inorganic N pool. In contrast, the KCl extractable organic N (KClEON) pool constituted the dominant form of soluble N in soils under all land uses, perhaps indicating that significant amounts were held on the soil exchange phase. In contrast to inorganic N, which varied significantly with land use, the size of the KClEON and WEON pool was similar for all land uses with the exception of KClEON in tilled land, where significantly lower amounts were observed. We conclude that SON constitutes an important soil N pool in a broad range of land uses, and that its role in microbial N assimilation, plant nutrition and ecosystem responses to atmospheric N deposition warrants further attention.
SAFRD, University of Newcastle, Newcastle-upon-Tyne, NE1 7RU, U.K. 相似文献
20.
Claudia Pahl-Wostl Georg Holtz Britta Kastens Christian Knieper 《Environmental Science & Policy》2010,13(7):571-581
This paper presents the Management and Transition Framework (MTF), an interdisciplinary conceptual and methodological framework supporting the analysis of water systems, management processes and multi-level governance regimes. It serves to improve the scientific understanding of system properties and to give practical guidance for the implementation of transition processes towards more adaptive systems. Doing so requires a systemic perspective to embrace complexity and the wealth of interactions characterizing resource governance regimes. The MTF supports and provides guidance for an interdisciplinary approach in the social sciences and across the social–natural science interface.The framework integrates a range of concepts to develop a more coherent understanding of the complexity of water management regimes. Specific emphasis is given to adaptive capacity and learning processes. However, the MTF is not linked to one specific theory but provides a language that can be tailored to specific research questions and different theoretical approaches. The structured yet flexible approach is a condition for developing shared databases that allow comparative analyses over a wider range of case studies. The MTF does not promote panaceas but a diagnostic approach supporting context sensitive analysis without being case specific and thus not directly transferable. 相似文献