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141.
Adaptation and mitigation strategies in agriculture: an analysis of potential synergies 总被引:3,自引:4,他引:3
Cynthia Rosenzweig Francesco Nicola Tubiello 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):855-873
As climate changes due to rising concentrations of greenhouse gases in the atmosphere, agriculture will be one of the key
human activities affected. Projections show that while overall global food production in the coming decades may keep pace
with the food requirements of a growing world population, climate change might worsen existing regional disparities because
it will reduce crop yields mostly in lands located at lower latitudes where many developing countries are situated. Strategies
to enhance local adaptation capacity are therefore needed to minimize climatic impacts and to maintain regional stability
of food production. At the same time, agriculture as a sector offers several opportunities to mitigate the portion of global
greenhouse gas emissions that are directly dependent upon land use, land-use change, and land-management techniques. This
paper reviews issues of agriculture and climate change, with special attention to adaptation and mitigation. Specifically,
as adaptation and mitigation strategies in agriculture are implemented to alleviate the potential negative effects of climate
change, key synergies need to be identified, as mitigation practices may compete with modifications to local agricultural
practices aimed at maintaining production and income. Under future climate and socio-economic pressures, land managers and
farmers will be faced with challenges in regard to selecting those mitigation and adaptation strategies that together meet
food, fiber and climate policy requirements. 相似文献
142.
We pursue a regression model for spatially-indexed data whose spatial correlation is determined by a linear combination of
simple covariograms. The main interest lies in the estimation of the spatial parameters. As several common techniques appear
ineffective for this setting, an algorithm is proposed to obtain parameter estimates and is assessed through simulation. It
is found to provide greater stability than other methods of estimation. We discuss the influence of parametrization and site
location on the efficacy of the estimation algorithms, and develop some guidelines as to the placement of sampling sites to
improve the algorithm's performance.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
143.
144.
Cynthia M. Kingsford Bruce E. Lindsay 《Journal of the American Water Resources Association》1987,23(5):845-848
ABSTRACT: New Hampshire's riparian water law, first modified judicially, has been more drastically changed by recent legislative and administrative action. As it stands, however, the judicially enforced doctrine of reasonable use appears to be utterly inadequate to handle increasing water demands. The protection of the public interest has imposed substantial limitations on the use of riparian water rights, all under the guise of the exercise of the police power, i.e., the protection of the public health, safety, and welfare. The efficient use of the state's water resources has been further crippled by the widespread and indiscriminate exercise of eminent domain. As a result, the state is now considering the imposition of a permit system that has the potential to streamline the allocation of water. Such a system should take into consideration the public interest factors that have recently frustrated the exercise of riparian rights and the effective use of the state's water resources. 相似文献
145.
In the current regulatory climate, environmental professionals are becoming increasingly involved with a side of the business that has often been given low priority in the past: communicating with the public about environmental and health risk issues. This article describes effective approaches to such communication, and demonstrates their implementation success. 相似文献
146.
Cynthia D. Fisher 《组织行为杂志》2003,24(6):753-777
Decades of research have shown that the correlation between job satisfaction and job performance is modest in magnitude, yet lay people are thought to believe strongly that satisfied or ‘happy’ employees are more productive at work. This paper first documents the strength and pervasiveness of belief in several versions of the happy–productive worker hypothesis (Study 1), then proposes and explores potential substantive explanations for these beliefs (Study 2). It is possible that lay people base their beliefs on genuinely stronger relationships that occur at a different level of analysis than usually studied by researchers, and/or that exist between satisfaction‐like and performance‐like variables other than the constructs typically investigated by scholars. Study 2 provides data relevant to several of these possibilities. The most compelling findings were at the within‐person level of analysis. The average within‐person correlation between momentary task satisfaction and concurrent perceived task performance was 0.57. Individuals feel more satisfied than usual when they believe they are performing better than usual for them. If lay persons mistakenly generalize from their own within‐person experiences of satisfaction–performance covariation to the between‐persons level, this relationship may be the basis for the strong lay belief that satisfied workers perform better. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
147.
Aline S. Turque Alexander M. Cardoso Cynthia B. Silveira Ricardo P. Vieira Flávia A. D. Freitas Rodolpho M. Albano Alessandra M. Gonzalez Rodolfo Paranhos Guilherme Muricy Orlando B. Martins 《Marine Biology》2008,155(2):135-146
In this study we performed a survey of the bacterial communities associated with the Western Atlantic demosponges Hymeniacidon heliophila and Polymastia janeirensis, based on 16S rRNA sequencing and transmission electron microscopy (TEM). We compared diversity and composition of the sponge-associated
bacteria to those of environmental bacteria, represented by free-living bacterioplankton and by bacteria attached to organic
particulate matter in superficial sediments. Partial bacterial 16S rRNA sequences from seawater, sediment, and sponges were
retrieved by PCR, cloning, and sequencing. Sequences were subjected to rarefaction analyses, phylogenetic tree construction,
and LIBSHUFF quantitative statistics to verify coverage and similarity between libraries. Community structure of the free-living
bacterioplankton was phylogenetically different from that of the sponge-associated bacterial assemblages. On the other hand,
some sediment-attached bacteria were also found in the sponge bacterial community, indicating that sponges may incorporate
bacteria together with sediment particles. Rare and few prokaryotic morphotypes were found in TEM analyses of sponge mesohyl
matrix of both species. Molecular data indicate that bacterial richness and diversity decreases from bacterioplankton, to
particulate organic sediment, and to H. heliophila and P. janeirensis. Sponges from Rio de Janeiro harbor a pool of novel and exclusive sponge-associated bacterial taxa. Sponge-associated bacterial
communities are composed of both taxons shared by many sponge groups and by species-specific bacteria. 相似文献
148.
The inarticulated brachiopod, Lingula reevii Davidson (1880) is a filter-feeding invertebrate that burrows vertically in sandy or mixed sediments. Its only recorded occurrence
is from Kaneohe Bay, Oahu, Hawaii, southern Japan, and Ambon, Indonesia. Past surveys of Kaneohe Bay populations suggested
a distinct decrease in abundance following the diversion of sewage effluent from the bay in 1978/1979. In the summer of 2004
and 2007, visual surveys were conducted in areas of historical L. reevii abundance as well as in areas appearing to have suitable habitat. In 2004, approximately 2,950 m2 at 20 sites within the bay were surveyed using quantitative belt transecting methods. A maximum density of 4 Lingula/m2 was observed, a decrease from previous maximum estimates of 500 individuals/m2 (Worcester, Dissertation, Zoology Department, University of Hawai′i, pp 49, 1969) and 100 individuals/m2 (Emig, J Exp Mar Biol Ecol 52:47–61, 1981). When these 20 sites were revisited in 2007, many had fewer or no L. reevii; therefore, broader scale presence/absence surveys were conducted at 16 additional sites in the bay (also surveyed in 2004).
The highest density of L. reevii found in 2007 was 0.94 individuals/m2. The continued decline in abundance of L. reevii in Kaneohe Bay may be due, in addition to decreased organic enrichment from diversion of sewage discharge almost 30 years
ago, to the more recent reduction of suitable habitat by the invasion of mat-forming alien algae species. 相似文献
149.
Cynthia?E.?BluteauEmail authorView authors OrcID profile Roger?Pieters Gregory?A.?Lawrence 《Environmental Fluid Mechanics》2017,17(3):579-590
Laboratory experiments have been performed to investigate the effects of salt exclusion on the behaviour of lakes with salinities up to 8 g L?1. At these salinities the freezing temperature is less than the temperature of maximum density and, unlike sea-ice, a reverse temperature stratification forms beneath the ice that can support at least some of the excluded salt. Temperature time series at four depths showed that salt exclusion drives cascades of localised overturning, while the persistence of reverse temperature stratification indicated that mixing was not complete. While our array of temperature sensors had insufficient spatial resolution to provide full details of the flow, we hypothesize that: at salinities of 1 and 2 g L?1 salt is released relatively uniformly and forms a layer of elevated salinity immediately below the ice, which supports double-diffusive salt-fingering; and at salinities of 4 and 8 g L?1, salt plumes penetrate the reverse stratification. After the ice melted, a relatively fresh surface layer formed above a more saline layer, sufficient to suppress spring turnover. Our measurements compare favourably with field observations from lakes, and highlight the importance of salt exclusion on biogeochemical processes in lakes. 相似文献
150.
Nozomi Kawarazuka Catherine Locke Cynthia McDougall Paula Kantor Miranda Morgan 《Ambio》2017,46(2):201-213
The demand for gender analysis is now increasingly orthodox in natural resource programming, including that for small-scale fisheries. Whilst the analysis of social–ecological resilience has made valuable contributions to integrating social dimensions into research and policy-making on natural resource management, it has so far demonstrated limited success in effectively integrating considerations of gender equity. This paper reviews the challenges in, and opportunities for, bringing a gender analysis together with social–ecological resilience analysis in the context of small-scale fisheries research in developing countries. We conclude that rather than searching for a single unifying framework for gender and resilience analysis, it will be more effective to pursue a plural solution in which closer engagement is fostered between analysis of gender and social-ecological resilience whilst preserving the strengths of each approach. This approach can make an important contribution to developing a better evidence base for small-scale fisheries management and policy. 相似文献