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791.
N. Dolgener L. Freudenberger N. Schneeweiss P. L. Ibisch R. Tiedemann 《Regional Environmental Change》2014,14(3):1063-1072
Environmental change is likely to have a strong impact on biodiversity, and many species may shift their distribution in response. In this study, we aimed at projecting the availability of suitable habitat for an endangered amphibian species, the Fire-bellied toad Bombina bombina, in Brandenburg (north-eastern Germany). We modelled a potential habitat distribution map based on (1) a database with 10,581 presence records for Bombina from the years 1990 to 2009, (2) current estimates for ecogeographical variables (EGVs) and (3) the future projection of these EGVs according to the statistical regional model, respectively, the soil and water integrated model, applying the maximum entropy approach (Maxent). By comparing current and potential future distributions, we evaluated the projected change in distribution of suitable habitats and identified the environmental variables most associated with habitat suitability that turned out to be climatic variables related to the hydrological cycle. Under the applied scenario, our results indicate increasing habitat suitability in many areas and an extended range of suitable habitats. However, even if the environmental conditions in Brandenburg may change as predicted, it is questionable whether the Fire-bellied toad will truly benefit, as dispersal abilities of amphibian species are limited and strongly influenced by anthropogenic disturbances, that is, intensive agriculture, habitat destruction and fragmentation. Furthermore, agronomic pressure is likely to increase on productive areas with fertile soils and high water retention capacities, indeed those areas suitable for B. bombina. All these changes may affect temporary pond hydrology as well as the reproductive success and breeding phenology of toads. 相似文献
792.
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794.
Ani Melkonyan P.h.D Malcolm O. Asadoorian P.h.D. 《Environment, Development and Sustainability》2014,16(2):393-414
With 21 % of gross domestic product (GDP) in agricultural sector and having consistently experienced natural disasters (e.g., drought, flood), Armenia is very vulnerable to climate and its change. Given the fact that 63 % of the entire land is planted with grains, this study primarily focuses on the market for wheat flour and bread. Economic welfare loss due to drought episodes is calculated using the economic data integrated with climate measures. Economic data are utilized for the period 1995–2011 (obtained from Statistical Office of Armenia) and specifically include the quantity produced and consumed of wheat flour and bread combined with mean prices, population income, GDP in the agricultural sector, GDP in the planting sector, and governmental expenditure on subsidies. Climate data include temperature and precipitation during the period 1966–2011 (obtained from National Hydrometeorological Service of Armenia). The analysis includes three main components. The first utilizes a market framework that analyzes the impact of climate on equilibrium prices and quantities as well as trade and tax effects. The second employs a logarithmic utility function to estimate the effective insurance policy for the agricultural sector using risk management strategies. Lastly, a macroeconomic model has been developed to assess the efficient sum of governmental expenditure on subsidies and irrigation during the drought episodes and during the mean climatic conditions. All three parts of the study are developed for the first time. 相似文献
795.
P. M. S. Jayathilaka Peeyush Soni Sylvain R. Perret H. P. W. Jayasuriya Vilas M. Salokhe 《Regional Environmental Change》2012,12(1):55-68
Climate change is the main global challenge of this century; it is therefore imperative to identify its effects on agriculture
in developing countries. This research makes spatial assessment of climate change effect on major plantation crops in Sri
Lanka, with emphasis on crop suitability of tea, rubber, and coconut. Geo-referenced maps of spatial and temporal changes
in crop suitability and production potentials are generated and compared. Data pertaining to six agro-ecological zones under
the study area are analyzed for a period of 1980–2007. Crop suitability maps are generated amalgamating yield maps and climatic
factors maps using AHP in multi-criteria analysis under two time frames of 1980–1992 and 1993–2007. Percent change in crop
suitability and crop yield classes is calculated based on five crop suitability and five crop yield classes during two time
frames. Dynamics of climatic parameters and crop yield are recognized using geo-referenced maps. The suitability maps of the
two time frames are compared to identify the changes with each crop in conjunction with changes in the prevailing climate
and yield. Geographic shift of suitability, yield, and climate classes are examined. Net gain or loss in crop production is
quantified. Long-term annual rainfall significantly decreased in mid-country wet zone, whereas the mean temperature of the
study area increased by 1.4°C. Results clearly showed that the climate and yield can be meaningfully related to the crop suitability
and management. 相似文献
796.
The food supply to a large metropolis such as Paris involves huge fluxes of goods, which considerably impact the surrounding rural territories. Here, we present an attempt to localise Paris food supply areas, over a period of two centuries (1786, 1886, 2006), based on the analysis of data from transportation and production statistics for cereals, animal products, and fruits and vegetables, all three categories being expressed in terms of their nitrogen (i.e. protein) content. The results show contrasting trends for the three types of agricultural products. As for cereals, the Paris supply area remained for the most part restricted to the central area of the Paris basin, a region which gradually became specialised in intensive cereal production. Conversely, as animal farming had been progressively excluded from this area, regions located west and north of Paris (Brittany, Normandy, Nord-Pas-de-Calais) gradually dominated the supply of animal products to the metropolis. In addition, imported feed from South America today contributes as much as one-third of the total ration of feed in the livestock raised in these regions. For fruits and vegetables, about one-half of the Paris supply currently comes from long-distance imports, the other half coming from areas less than 200 km from Paris. As a whole, the Paris food supply area, although it has obviously enlarged in recent periods, is still anchored to an unexpected extent (about 50%) in its traditional nearby hinterland roughly coinciding with the Seine watershed, and in the regions specialised in animal farming located west and north. On the other hand, the agricultural system of the main food supply areas has considerably opened to global markets. 相似文献
797.
Richard Grossman 《Environment, Development and Sustainability》2012,14(6):973-977
Human population growth challenges efforts toward sustainability. People who are concerned about the environment, development, and sustainability are in a position to stress the importance of human population and to encourage people to choose small family size (Grossman, in Conserv Biol, 24(6), pp 1435–1436, 2010). Nevertheless, this vital subject has been treated infrequently in this journal. Of more than 500 articles published since its inception, only 15 have touched on human population, few have had population as a primary subject and only three have suggested that readers of this journal can and should have influence over population growth. This article concludes by suggesting ways that we who are concerned about sustainability should promote education about family planning and the advantages of small family size. 相似文献
798.
Zhu Ting Ganesh P. Shivakoti Chen Haiyun David Maddox 《Environment, Development and Sustainability》2012,14(2):197-220
Community-based co-management (CBCM) mechanisms for forest management have matured through the development of new economic
analysis and common property theory. However, while many local CBCM mechanisms have been initiated in Chinese Natural Reserves,
there are few objective, data-based evaluations of whether these mechanisms improve forest conservation and local livelihoods.
This research uses Baishuijiang National Natural Reserve (BNNR) as a study case to evaluate China’s current CBCM mechanisms.
The evaluation is based mainly on three criteria: efficiency, equality and sustainability of project operation. Survey data
indicate that local CBCM mechanisms provide a wide-participation platform for local villagers, associated administration managers,
research institutions and NGOs to join in forest resource protection work while improving local livelihood. CBCM projects
have also facilitated a reduction in forest resource dependency, the improvement of household income and encouragement of
local people to participate in forest resource protection. Our analysis suggests that most CBCM organizations have made progress
in efficiency, equity and sustainability. However, further study should focus on how to deal with the lingering problems of
inequity in responsibility and rights among CBCM committee members, poor distribution of benefits, insufficient program-design
and management expertise, faulty information dissemination, and insufficient capital investment. 相似文献
799.
To restore food security to a traditional African cropping system following a sudden loss of seed, genetic diversity must be re-established. This study examines the extent to which Cowpea diversity was reinstated two years after a flood disaster in Gaza Province, Mozambique. The contribution that seed from various sources made to the recovery was assessed using semi-structured interviews and morphological and molecular data. Data suggest that diversity had recovered to some extent yet there was evidence of a narrowing of the genetic base, with fewer rare alleles and differences in the distribution of allele frequencies. Although the main channels for accessing seed after the flood were seed relief and markets, these sources contributed to minimal and different diversity. It appears that diversity was regained primarily through social networking in the form of loans or gifts of seed from friends and relatives. The results of the study are discussed in relation to seed relief approaches. 相似文献
800.
M. A. Potapov I. V. Zadubrovskaya P. A. Zadubrovskii O. F. Potapova V. I. Evsikov 《Russian Journal of Ecology》2012,43(1):40-44
A comparative analysis of reproductive behavior has been performed in the steppe lemming (Lagurus lagurus) and narrow-skulled vole (Microtus gregalis). The results show that the species are similar in certain behavioral features indicative of the stability of mating pairs.
However, in the narrow-skulled vole, unlike in the steppe lemming, mature males in olfactory tests show preference for receptive
sibling females versus non-kin females. Probably, it is the absence of the incest taboo that allows the involvement of young
of the year in reproduction within growing family groups and accounts for “coloniality” of the species. 相似文献