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291.
Use of Descriptors of Ecosystem Functioning for Monitoring a National Park Network: A Remote Sensing Approach 总被引:1,自引:0,他引:1
Baseline assessments and monitoring of protected areas are essential for making management decisions, evaluating the effectiveness
of management practices, and tracking the effects of global changes. For these purposes, the analysis of functional attributes
of ecosystems (i.e., different aspects of the exchange of matter and energy) has advantages over the traditional use of structural
attributes, like a quicker response to disturbances and the fact that they are easily monitored through remote sensing. In
this study, we described the spatiotemporal patterns of different aspects of the ecosystem functioning of the Spanish national
parks and their response to environmental changes between 1982 and 2006. To do so, we used the NOAA/AVHRR-GIMMS dataset of
the Normalized Difference Vegetation Index (NDVI), a linear estimator of the fraction of photosynthetic active radiation intercepted
by vegetation, which is the main control of carbon gains. Nearly all parks have significantly changed during the last 25 years:
The radiation interception has increased, the contrast between the growing and nongrowing seasons has diminished, and the
dates of maximum and minimum interception have advanced. Some parks concentrated more changes than others and the degree of
change varied depending on their different environmental conditions, management, and conservation histories. Our approach
identified reference conditions and temporal changes for different aspects of ecosystem functioning, which can be used for
management purposes of protected areas in response to global changes. 相似文献
292.
Acid sulfate soils have been described as the “nastiest soils on earth” because of their strong acidity, increased mobility of potentially toxic elements and limited bioavailability of nutrients. They only cover a small area of the world's total problem soils, but often have significant adverse effects on agriculture, aquaculture and the environment on a local scale. Their location often coincides with high population density areas along the coasts of many developing countries. As a result, their negative impacts on ecosystems can have serious implications to those least equipped for coping with the low crop yields and reduced water quality that can result from acid sulfate soil disturbance. The Millennium Ecosystem Assessment called on by the United Nations in 2000 emphasised the importance of ecosystems for human health and well-being. These include the service they provide as sources of food and water, through the control of pollution and disease, as well as for the cultural services ecosystems provide. While the problems related to agriculture, aquaculture and the environment have been the focus of many acid sulfate soil management efforts, the connection to human health has largely been ignored. This paper presents the potential health issues of acid sulfate soils, in relation to the ecosystem services identified in the Millennium Ecosystem Assessment. It is recognised that significant implications on food security and livelihood can result, as well as on community cohesiveness and the spread of vector-borne disease. However, the connection between these outcomes and acid sulfate soils is often not obvious and it is therefore argued that the impact of such soils on human well-being needs to be recognised in order to raise awareness among the public and decision makers, to in turn facilitate proper management and avoid potential human ill-health. 相似文献
293.
Gudrun Koppen Elly Den Hond Vera Nelen Els Van De Mieroop Liesbeth Bruckers Maaike Bilau Hans Keune Nicolas Van Larebeke Adrian Covaci Hendrik Van De Weghe Carmen Schroijen Kristine Desager Michel Stalpaert Willy Baeyens Greet Schoeters 《Environment international》2009,35(7):1015-1022
To collect regional information on internal levels of pollutants in humans in Flanders, 1196 mother–child pairs were systematically recruited in 2002–2003 via 25 maternities across Flanders. Cd, Pb, PCB congeners 118, 170, 138, 153 and 180, p,p′-DDE — a key metabolite of DDT- and hexachlorobenzene (HCB) were measured in cord blood or plasma. Cd was detected in 64% of the samples (geometric mean 0.21 µg/L cord blood). p,p′-DDE (110 ng/g plasma lipids) and Pb (14.7 µg/L blood), were measurable in nearly all samples. The individual PCB congeners could be detected in 40 to 81% of the newborns (138 + 153 + 180 = 64.4 ng/g plasma lipids). HCB (18.9 ng/g plasma lipids) and dioxin-like compounds measured by DR-CALUX® (23 pg CALUX-TEQ/g lipids) were above detection limit in more than 75% of the samples. Age and smoking habits of the mothers, did not influence the cord blood Pb and Cd levels. The organochlorines increased 4 to 9% per year of the mother's age (partial R2 = 0.05 to 0.22). Mothers had 2.6% less PCBs in cord blood (partial R2 = 0.02) for each unit increase in pre-pregnancy BMI. Season of delivery, breastfeeding previous children or consumption of local dairy products, were minor determinants. Up to 20% of the variability in organochlorine concentrations was explained by residence area. It was concluded that the place of birth in Flanders is an important determinant of the load of pollutants measured at the start of life. This underlines the validity of human biomonitoring on (relatively) small geographical scale. 相似文献
294.
Protection of the environment from ionising radiation in a regulatory context (protect): proposed numerical benchmark values 总被引:1,自引:1,他引:0
295.
The system of radiological protection of the environment that is currently under development is one contribution to the general need to adequately protect the environment against stress. Dominated by operational goals, it emphasizes conceptual and methodological approaches that are readily accessible today: reference organisms supported by individual-based traditional ecotoxicological data. Whilst there are immediate advantages to this approach (pragmatism, consistency with other approaches in use for man and biota), there are also clear limitations, especially in a longer run perspective, that need to be acknowledged and further considered. One can mention a few: uncertainties generated by the need for various extrapolations (from lower to higher levels of biological organisation, …), various features missed such as potential ecological impact through impairment of ecosystem processes, trans-generational impacts as mediated through genomic instability, indirect effects mediated through trophic interactions or disruption of ecological balances,… Such limitations have already been faced in other fields of environmental protection against other stressors, pushing a number of environment professionals to assign stronger emphasis on more systemic approaches. This review discusses the advantages and limitations of the current approach designed for the radiological protection of non-human biota in the broader context of environment protection as a whole, with especial reference to upcoming trends and evolutions. This leads in particular to advocating the need to boost scientific and methodological approaches featuring the ecosystem concept as a mean to access a unified goal of protection: preserving life sustainability through protection of ecosystem structure and functioning. 相似文献
296.
New best estimates for the solid–liquid distribution coefficient (Kd) for a set of radionuclides are proposed, based on a selective data search and subsequent calculation of geometric means. The Kd best estimates are calculated for soils grouped according to the texture and organic matter content. For a limited number of radionuclides this is extended to consider soil cofactors affecting soil–radionuclide interaction, such as pH, organic matter content, and radionuclide chemical speciation. Correlations between main soil properties and radionuclide Kd are examined to complete the information derived from the best estimates with a rough prediction of Kd based on soil parameters. Although there are still gaps for many radionuclides, new data from recent studies improve the calculation of Kd best estimates for a number of radionuclides, such as selenium, antimony, and iodine. 相似文献
297.
This paper focuses on comparative review and analysis of the systems of environmental protection, national environmental strategies
and fundamentals of environmental legislation in Australia and the Russian Federation. These countries have many socioeconomic
similarities, such as low population densities and richness in natural resources which are largely exported. The main disparity
between Australia and Russia is in the types of economy. This paper ‘continues’ the sequence of recent scholarly publications
on comparison of various features of environmental policies in the countries from all over the world. Comparative analysis
in this research has been based on examination of scholarly publications, legislation, government documents, mass media sources
and NGO responses. The analysis has revealed a number of differences including top-down implementation of policies in Russia
whereas in Australia, each State (Territory) implements policies with significant independence from the Commonwealth Government.
At the same time, similarities between the countries have been identified: for example, in deficits in the budget of local
environmental authorities and in the presence of contradictions in legislation at national and regional levels of government.
Suggestions resulting from this analysis include further integration of sustainable development strategies at all levels of
Australian government to encourage further protection of the environment and, for Russia, creating a separate Ministry of
Environmental Protection. These approaches should assist facilitation of sustainable development for both nations.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
298.
Gilles Billen Sabine Barles Josette Garnier Joséphine Rouillard Paul Benoit 《Regional Environmental Change》2009,9(1):13-24
Between the tenth and twentieth century the population of Paris city increased from a few thousand to near 10 million inhabitants.
In response to the growing urban demand during this period, the agrarian systems of the surrounding rural areas tremendously
increased their potential for commercial export of agricultural products, made possible by a surplus of agricultural production
over local consumption by humans and livestock in these areas. Expressed in terms of nitrogen, the potential for export increased
from about 60 kg N/km2/year of rural territory in the Middle Ages, to more than 5,000 kg N/km2/year from modern agriculture.
As a result of the balance between urban population growth and rural productivity, the rural area required to supply Paris
(i.e. its food-print) did not change substantially for several centuries, remaining at the size of the Seine watershed surrounding
the city (around 60,000 km2). The theoretical estimate of the size of the supplying hinterland at the end of the eighteenth
century is confirmed by the figures deduced from the analysis of the historical city toll data (octroi). During the second
half of the twentieth century, the ‘food-print’ of Paris reduced in size, owing to an unprecedented increase in the potential
for commercial export associated with modern agricultural systems based on chemical N fertilization. We argue that analysing
the capacity of territories to satisfy the demand for nitrogen-containing food products of local or distant urban population
and markets might provide new and useful insights when assessing world food resource allocation in the context of increasing
population and urbanization. 相似文献
299.
Hg concentrations and related risk assessment in coral reef crustaceans, molluscs and fish from New Caledonia 总被引:1,自引:0,他引:1
Chouvelon T Warnau M Churlaud C Bustamante P 《Environmental pollution (Barking, Essex : 1987)》2009,157(1):331-340
There is a dramatic lack of data on Hg levels in marine organisms from tropical areas, and in particular from New Caledonia. For the first time, this study reports the total Hg concentrations in the tissues of several marine taxa from the New Caledonian lagoon. Seafood from both wild and farmed populations was considered. Hg concentrations varied over three orders of magnitudes according to factors including species, age (size/weight), trophic level, lifestyle and geographical origin. Taking into account the edible tissues, estimations of the amount of flesh that should be consumed by a 60-kg person to reach the Hg Provisional Tolerable Weekly Intake (PTWI) reveal acceptable risk for Human health in general. However, a risk was clearly identified in one site of the lagoon (i.e. Grande Rade) where high Hg concentrations were measured. These concentrations were higher than values reported in the current literature. 相似文献
300.
A survey on the public perception of CCS in France 总被引:2,自引:0,他引:2
Minh Ha-Duong Alain Nadaï Ana Sofía Campos 《International Journal of Greenhouse Gas Control》2009,3(5):633-640
An awareness and opinion survey on carbon capture and storage (CCS) was conducted on a representative sample of French residents aged 15 years and above. About 6% of respondents were able to provide a satisfactory definition of the technology. The key question about ‘approval of or opposition to’ the use of CCS in France was asked twice, first after presenting the technology, then after explaining its potential adverse consequences. The approval rates, which were 59% and 38%, respectively, show that there is no a priori rejection of the technology. The sample was split in two to test for a semantic effect: half of the questionnaires used “Stockage” (English: storage), the other half “Sequestration”. Manipulating the vocabulary had no statistically significant effect on approval rates. Stockage is more meaningful, but does not convey the idea of permanent monitoring. 相似文献