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61.
Stephen M. Ogle Lydia Olander Lini Wollenberg Todd Rosenstock Francesco Tubiello Keith Paustian Leandro Buendia Alison Nihart Pete Smith 《Global Change Biology》2014,20(1):1-6
Agriculture in developing countries has attracted increasing attention in international negotiations within the United Nations Framework Convention on Climate Change for both adaptation to climate change and greenhouse gas mitigation. However, there is limited understanding about potential complementarity between management practices that promote adaptation and mitigation, and limited basis to account for greenhouse gas emission reductions in this sector. The good news is that the global research community could provide the support needed to address these issues through further research linking adaptation and mitigation. In addition, a small shift in strategy by the Intergovernmental Panel on Climate Change (IPCC) and ongoing assistance from agricultural organizations could produce a framework to move the research and development from concept to reality. In turn, significant progress is possible in the near term providing the basis for UNFCCC negotiations to move beyond discussion to action for the agricultural sector in developing countries. 相似文献
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Olli Salmi Janne Hukkinen Jyrki Heino Nani Pajunen Maaria Wierink 《Journal of Industrial Ecology》2012,16(1):119-128
Many scholars of industrial ecology have focused on the institutional and organizational challenges of building and maintaining regional industrial symbiosis through the synergistic integration of material and energy flows. Despite the promise that these intellectual developments hold for the future dematerialization of industrial production, they rarely address the actual regulatory obstacles of turning wastes into raw materials. In this article we introduce a potential future industrial symbiosis around the Gulf of Bothnia between Finland and Sweden, and assess the regulatory bottlenecks related to waste by‐product consideration. We find that although the Gulf of Bothnia region has technological and economic potential for industrial symbiosis, the regulatory support for this is insufficient. We suggest a common pool resource‐based governance system that could utilize market and regulatory mechanisms in a regional‐level cross‐border system of governance. Importantly, the suggested governance system would protect the users of potential raw materials from unpredictable waste regulation, market risks related to large‐scale material flows, and societal risks of hazardous waste treatment. 相似文献
64.
R. Shyama Prasad Rao Ian Max Møller 《Biochimica et Biophysica Acta - Proteins and Proteomics》2012,1824(3):405-412
Many recent high throughput technologies have enabled large-scale discoveries of new phosphorylation sites and phosphoproteins. Although they have provided a number of insights into protein phosphorylation and the related processes, an inclusive analysis on the nature of phosphorylated sites in proteins is currently lacking. We have therefore analyzed the occurrence and occupancy of phosphorylated sites (~ 100,281) in a large set of eukaryotic proteins (~ 22,995). Phosphorylation probability was found to be much higher in both the termini of protein sequences and this is much pronounced in transmembrane proteins. A large proportion (51.3%) of occupied sites had a nearby phosphorylation within a distance of 10 amino acids; however, this proportion is very high compared to the expected one (16.9%). The distribution of phosphorylated sites in proteins showed a strong deviation from the expected maximum randomness. An analysis of phosphorylation motifs indicated that just 40 motifs and a much lower number of associated kinases might account for nearly 50% of the known phosphorylations in eukaryotic proteins. Our results provide a broad picture of the phosphorylation sites in eukaryotic proteins. 相似文献
65.
L. Benejam E. Aparicio M. J. Vargas A. Vila-Gispert E. García-Berthou 《Hydrobiologia》2008,603(1):197-210
Implementation of the Water Framework Directive requires tools for measuring and monitoring the ecological status of aquatic
ecosystems. Several indices are in use in the Iberian Peninsula, although there has been little comparison among them. We
sampled the fish assemblage and limnological features of the Tordera stream (NE Spain) quarterly from September 2001 to May
2003 to evaluate the usefulness of several fish metrics and to compare habitat quality and biotic indices currently in use.
Data for eight biotic and abiotic indices for this and three other Catalan river basins were also compiled in order to analyse
the relationships among indices. In the Tordera stream, fish abundance and richness increased with stream order except in
the last sampling site that had the lowest fish abundance owing to the effects of drought and water abstraction. Although
most indices were positively correlated, some displayed low or null correlations particularly for the Tordera basin which
is more affected by water abstraction and less by pollution; a commonly used physico-chemical index (ISQA) was the least correlated.
In a regional fish index (IBICAT) under development, the brown trout (Salmo trutta) has been previously considered as introduced in the Tordera basin. Here, we report an old published record that demonstrates
that trout was present before 1845 and we argue that its status should be considered as uncertain given the current information
available. Whether brown trout is treated as native or introduced to this river basin has profound effects on the results
of fish metrics because of its dominance in the upper reaches. We briefly discuss the role of introduced species, particularly
in headwater streams, in the development of fish indices. Our study exemplifies the need for careful, basin-specific assessment
of native/introduced status in the development of fish metrics.
Handling editor: K. Martens 相似文献
66.
The effect of restoring connectivity for fish by the construction of 11 fish ladders in the Pielach and Melk rivers, both
tributaries to the Danube in Austria, was monitored using electric fishing and fish traps between 1999 and 2004. In order
to assess the efficiency of connectivity rehabilitation measures pre- and post-project data combining electric fishing and
trap catch data were analyzed by means of three fish-based assessment methods: a MUlti-Level concept for a Fish-based, river-type-specific
Assessment of ecological integrity (MULFA), the Fish Index Austria (FIA) and the European Fish Index (EFI). The effect of
adding qualitative trap catch data to electric fishing data on metrics and indices was also tested and the magnitude of the
effect was related to the distance of the sites from the river mouth. The results clearly demonstrated the significant contribution
of connectivity rehabilitation measures to the ecological integrity of rivers like the River Pielach where morphological conditions
are good, whereas remaining channelization still limits the success of connectivity measures in the River Melk. Trap catch
data were found to represent an essential source of additional information to assess the efficiency of connectivity measures
shortly after their implementation. The negative correlations of the magnitude of the effect of different indices and metrics
with the distance of assessment sites from river mouths obviously underline the importance of the river Danube as a source
for the re-colonization process. While the indices tested were found to have limited ability to reflect short-term response
of fish assemblages to continuum rehabilitation, guild metrics were able to detect improvements of the ecological status shortly
after the implementation of connectivity measures. Six metrics showed significant differences between pre and post-project
data reflecting the expected increase of the ecological integrity: (1) Fish Region Index (FRI; FIA, MULFA), (2) number of
subdominant species and (3) number of flow-guilds (FIA), (4) number of type specific species (MULFA), (5) number of benthic
species and (6) number of potamodromous species (EFI); the FRI differences were only significant when trap catch data were
added. The EFI indicated a decline of ecological integrity through increases in the density of omnivorous species and the
relative number of tolerant species as well as a decrease in the relative number of intolerant species. Significantly decreasing
responses with the distance from the river mouth were documented by the EFI and MULFA-index, the FRI (FIA, MULFA), total biomass
and for the number of type specific species (MULFA).
Guest editors: R. L. Welcomme & G. Marmulla
Hydropower, Flood Control and Water Abstraction: Implications for Fish and Fisheries 相似文献
67.
Highlights of large lake research and management in Europe 总被引:1,自引:0,他引:1
Peeter Nõges Külli Kangur Tiina Nõges Anu Reinart Heikki Simola Markku Viljanen 《Hydrobiologia》2008,599(1):259-276
Lakes in Europe have a bipolar distribution by latitude with higher lake densities in the north (58–65° N) and south (38–48° N). By area, 95% of the large lakes (>100 km2) are located at altitudes lower than 100 m above sea level (ASL) and only 1% lie higher than 1,000 m ASL. Physically large lakes exhibit several similarities to seas and oceans in their thermal structure and circulation dynamics. From the chemical point of view, lakes are important accumulation sites for substances transported from the watershed or built up in the lake itself but they may contribute positively to global greenhouse gas emission. Fauna and flora of ancient large lakes such as the Caspian Sea and Lake Ohrid include large numbers of endemic species, which become endangered if conditions change because of direct human impact, alien species invasions or climate change. Large lakes offer a wide range of ecosystem services to society, the multiple use of which creates multiple pressures on these water bodies such as nutrient load and toxic pollution, modification of hydrology and shore line structure, and shifting of the food web balance by stocking or harvesting various species. Although large lakes are among the best-studied ecosystems in the world, the application to them of environmental regulations such as the European Water Framework Directive is a challenging task and requires that several natural and management aspects specific to these water bodies are adequately considered. 相似文献
68.
CASSANDRA JAMES JANE FISHER VICTORIA RUSSELL SALLY COLLINGS & BRIAN MOSS 《Freshwater Biology》2005,50(6):1049-1063
1. Submerged plant richness is a key element in determining the ecological quality of freshwater systems; it has often been reduced or completely lost. 2. The submerged and floating‐leaved macrophyte communities of 60 shallow lakes in Poland and the U.K. have been surveyed and species richness related to environmental factors by general linearised models. 3. Nitrogen, and more specifically winter nitrate, concentrations were most important in explaining species richness with which they were inversely correlated. Phosphorus was subsidiary. Such an inverse relationship is consistent with findings in terrestrial communities. Polish lakes, with less intensively farmed catchments, had greater richness than the U.K. lakes. 4. The richest U.K. communities were associated with winter nitrate‐N concentrations of up to about 1–2 mg L?1 and may correspond with ‘good’ ecological quality under the terms of the European Water Framework Directive. Current concentrations in European lowlands are often much higher. 相似文献
69.
Panayotis Panayotidis Barbara Montesanto Sotiris Orfanidis 《Journal of applied phycology》2004,16(1):49-59
Benthic macroalgal communities constitute one of the ecological quality elements needed to implement the Water Framework Directive
(2000/60/EC), the legislation targetted at sustainable management of the European aquatic environment. As the Directive foresees
the establishment of Ecological Status Class boundaries and Reference Conditions in coastal waters, a study was conducted
on the Attica coast of Greece to identify the best method to use macroalgal community data for evaluating ecological quality
and at the same time keep the program within a low budget. Six seasonal quantitative and qualitative samples were taken from
the upper infralittoral macroalgal communities on the Attica coast of Greece on six occasions between summer 1998 and spring
2002; these sites, which reflect a gradient of anthropogenic perturbation, were used on each occasion. A list of 60 macroalgal
taxa was prepared, the cover value of each taxon was measured and the structure of the vegetation was described. The use of
four different indices (Shannon-Weaver index, Pielou evenness, Multi-Dimensional Scaling plot of Bray-Curtis similarity, Ecological
Evaluation index-EEI) were compared. The multidimensional scaling of Bray-Curtis similarity and the EEI were better at indicating
the perturbation pattern of the study area. However, only the EEI succeeded in distinguishing four quality classes (‘low’
to ‘high’). By using EEI, a spatial scale-weighted evaluation of ecological quality was also performed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
70.
一种作物种植的气候适应性模糊综合评价方法的探讨 总被引:2,自引:0,他引:2
提出了一种作物种植的气候适应性的模糊综合评价方法.作物种植的气候适应性可定义为一定地理环境下,其自然气候条件能满足作物生长所需适宜气候条件的能力.在相同的地理环境下,作物种植的气候适应性因作物种类不同而表现不一,并可表示为该地理环境提供的自然气候条件对不同作物生长所需适宜气候条件的满足程度.作物种植的气候适应性的模糊综合评价包括以下主要步骤:确定影响作物种植的主要气候因子,确定各因子的权重,建立评价因子集并确定气候因子评价标准、建立评价矩阵和计算作物生长气候适应性等.采用该方法对武夷山北坡不同海拔高度柑桔和茶树种植的气候适应性进行了综合评价. 相似文献