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221.
Mapping bundles of ecosystem services reveals distinct types of multifunctionality within a Swedish landscape 总被引:1,自引:0,他引:1
Cibele Queiroz Megan Meacham Kristina Richter Albert V. Norström Erik Andersson Jon Norberg Garry Peterson 《Ambio》2015,44(1):89-101
Ecosystem services (ES) is a valuable concept to be used in the planning and management of social–ecological landscapes. However, the understanding of the determinant factors affecting the interaction between services in the form of synergies or trade-offs is still limited. We assessed the production of 16 ES across 62 municipalities in the Norrström drainage basin in Sweden. We combined GIS data with publically available information for quantifying and mapping the distribution of services. Additionally, we calculated the diversity of ES for each municipality and used correlations and k-means clustering analyses to assess the existence of ES bundles. We found five distinct types of bundles of ES spatially agglomerated in the landscape that could be explained by regional social and ecological gradients. Human-dominated landscapes were highly multifunctional in our study area and urban densely populated areas were hotspots of cultural services. 相似文献
222.
223.
Barbara J. Smallwood R. Paul Philp Thomas W. Burgoyne Jon D. Allen 《Environmental Forensics》2013,14(3):215-221
The recent controversy over the use of MTBE within gasoline to boost oxygen content and decrease carbon monoxide emissions to the atmosphere has led to a proposed phase-out of this compound by 2002. This paper is a preliminary investigation into the use of gas chromatography isotope-ratio mass spectrometry (GCIRMS) to determine both carbon and hydrogen isotopic compositions of MTBE as a means of differentiating sources of MTBE. Three pure MTBE samples were purchased from chemical distributors. Little variation of the i 13 C values were observed although the samples had isotopically distinct i -D values. Four different methods of obtaining carbon isotope ratios of neat MTBE, MTBE in gasoline, and MTBE in water are described, and the precision and accuracy of each is discussed. The carbon isotopic compositions of MTBE within 10 gasoline samples from three different areas of the United States show a wide range of carbon isotope compositions. This novel method of MTBE analysis could be valuable in forensic investigations. 相似文献
224.
Vulnerability to climate variability and change in East Timor 总被引:2,自引:0,他引:2
This paper presents the results of a preliminary study of climate vulnerability in East Timor. It shows the results of projections of climate change in East Timor. The country's climate may become hotter, drier, and increasingly variable. Sea levels are likely to rise. The paper then considers the implications of these changes on three natural resources--water, soils, and the coastal zone--and finds all to be sensitive to changes in climate and sea level. Changes in the abundance and distribution of these resources is likely to cause a reduction in agricultural production and food security, and sea-level rise is likely to damage coastal areas, including Dili, the capital city. 相似文献
225.
Hatim O. Sharif Almoutaz A. Hassan Sazzad Bin-Shafique Hongjie Xie Jon Zeitler 《Journal of the American Water Resources Association》2010,46(5):881-891
Sharif, Hatim O., Almoutaz A. Hassan, Sazzad Bin-Shafique, Hongjie Xie, and Jon Zeitler, 2010. Hydrologic Modeling of an Extreme Flood in the Guadalupe River in Texas. Journal of the American Water Resources Association (JAWRA) 1-11. DOI: 10.1111/j.1752-1688.2010.00459.x Abstract: Many of the storms creating the greatest rainfall depths in Texas, measured over durations ranging from one minute to 48 hours, have occurred in the Texas Hill Country area. The upstream portion of the Guadalupe River Basin, located in the Texas Hill Country, is susceptible to flooding and rapid runoff due to thin soils, exposed bedrock, and sparse vegetation, in addition to the Balcones Escarpment uplift contributing to precipitation enhancement. In November 2004, a moist air mass from the Gulf of Mexico combined with moist air from the Pacific Ocean resulted in the wettest November in Texas since 1895. Although the peak discharges were not the highest on record, the U.S. Geological Survey (USGS) stream gauge on the Guadalupe River at Gonzales, Texas reported a daily mean discharge of 2,304 m3/s on November 23, 2004 (average discharge is 53 m3/s). In this paper, we examine the meteorological conditions that led to this event and apply a two-dimensional, physically based, distributed-parameter hydrologic model to simulate the response of a portion of the basin during this event. The study results clearly demonstrate the ability of physically based, distributed-parameter simulations, driven by operational radar rainfall products, to adequately model the cumulative effect of two rainfall events and route inflows from three upstream watersheds without the need for significant calibration. 相似文献
226.
This paper examines potential effects of predicted climate changes on the forage conditions during both summer and winter for semidomesticated reindeer in Sweden. Positive effects in summer ranges include higher plant productivity and a longer growing season, while negative effects include increased insect harassment. Forage quality may change in both positive and negative ways. An increase in shrubs and trees in alpine heaths is also likely. A warmer climate means shorter winters, which will have positive effects for the survival of reindeer. However, warmer and wetter weather may also result in increased probabilities of ice-crust formations, which strongly decrease forage availability. A warmer climate with higher forest productivity will also likely reduce lichen availability through competitive interactions. Adaptations to these changes will include maintaining a choice of grazing sites in both summer and winter. However, this capacity may already be severely limited because of other forms of land use. 相似文献
227.
Design principles and common pool resource management: an institutional approach to evaluating community management in semi-arid Tanzania 总被引:1,自引:0,他引:1
This paper analyses the role of institutions in the management of common pool resources (CPRs) in semi-arid Tanzania. Common property regimes have often been considered inadequate for the management of CPRs because of the problems of excludability, but they are becoming more widely supported as the way forward to overcome the problems of resource use and degradation in developing countries. A series of design principles for long enduring common property institutions have been proposed by Ostrom, but there is concern that they are not applicable to a wide range of real life situations or that they may be specific to certain types of CPR. Here, we compare these principles to the situation prevailing in 12 villages in six districts in semi-arid Tanzania. Data on management institutions were collected through semi-structured interviews and meetings at district and village level. The combined information was used to make a qualitative assessment of the strength with which each design principle appeared to operate in the management of forest, pasture and water resources. Boundaries, conflict and negotiation in CPR management are of key importance in semi-arid regions. However, the need for flexibility in order to deal with ecological uncertainty means that many management institutions would be considered weak or absent according to the design principle approach. This supports the view that the design principles should not be used as a 'blueprint to be imposed on resource management regimes' rather that they provide a framework for investigating common property regimes with the proviso that, certainly for semi-arid regions, they may highlight where management cannot be explained by institutional theory alone. 相似文献
228.
Rastall AC Getting D Goddard J Roberts DR Erdinger L 《Environmental science and pollution research international》2006,13(4):256-267
Goal, Scope and Background
Some anthropogenic pollutants posses the capacity to disrupt endogenous control of developmental and reproductive processes
in aquatic biota by activating estrogen receptors. Many anthropogenic estrogen receptor agonists (ERAs) are hydrophobic and
will therefore readily partition into the abiotic organic carbon phases present in natural waters. This partitioning process
effectively reduces the proportion of ERAs readily available for bioconcentration by aquatic biota. Results from some studies
have suggested that for many aquatic species, bioconcentration of the freely-dissolved fraction may be the principal route
of uptake for hydrophobic pollutants with logarithm n-octanol/water partition coefficient (log Kow) values less than approximately
6.0, which includes the majority of known anthropogenic ERAs. The detection and identification of freely-dissolved readily
bioconcentratable ERAs is therefore an important aspect of exposure and risk assessment. However, most studies use conventional
techniques to sample total ERA concentrations and in doing so frequently fail to account for bioconcentration of the freely-dissolved
fraction. The aim of the current study was to couple the biomimetic sampling properties of semipermeable membrane devices
(SPMDs) to a bioassay-directed chemical analysis (BDCA) scheme for the detection and identification of readily bioconcentratable
ERAs in surface waters.
Methods
SPMDs were constructed and deployed at a number of sites in Germany and the UK. Following the dialytic recovery of target
compounds and size exclusion chromatographic clean-up, SPMD samples were fractionated using a reverse-phase HPLC method calibrated
to provide an estimation of target analyte log Kow. A portion of each HPLC fraction was then subjected to the yeast estrogen
screen (YES) to determine estrogenic potential. Results were plotted in the form of 'estrograms' which displayed profiles
of estrogenic potential as a function of HPLC retention time (i.e. hydrophobicity) for each of the samples. Where significant
activity was elicited in the YES, the remaining portion of the respective active fraction was subjected to GC-MS analysis
in an attempt to identify the ERAs present.
Results and Discussion
Estrograms from each of the field samples showed that readily bioconcentratable ERAs were present at each of the sampling
sites. Estimated log Kow values for the various active fractions ranged from 1.92 to 8.63. For some samples, estrogenic potential
was associated with a relatively narrow range of log Kow values whilst in others estrogenic potential was more widely distributed
across the respective estrograms. ERAs identified in active fractions included some benzophenones, various nonylphenol isomers,
benzyl butyl phthalate, dehydroabietic acid, sitosterol, 3-(4-methylbenzylidine)camphor (4-MBC) and 6-acetyl-1,1,2,4,4,7-hexamethyltetralin
(AHTN). Other tentatively identified compounds which may have contributed to the observed YES activity included various polycyclic
aromatic hydrocarbons (PAHs) and their alkylated derivatives, methylated benzylphenols, various alkylphenols and dialkylphenols.
However, potential ERAs present in some active fractions remain unidentified.
Conclusions and Outlook
Our results show that SPMD-YES-based BDCA can be used to detect and identify readily bioconcentratable ERAs in surface waters.
As such, this biomimetic approach can be employed as an alternative to conventional methodologies to provide investigators
with a more environmentally relevant insight into the distribution and identity of ERAs in surface waters. The use of alternative
bioassays also has the potential to expand SPMD-based BDCA to include a wide range of toxicological endpoints. Improvements
to the analytical methodology used to identify ERAs or other target compounds in active fractions in the current study could
greatly enhance the applicability of the methodology to risk assessment and monitoring programmes. 相似文献
229.
230.
Polybrominated diphenyl ethers (PBDEs) have become widely distributed as environmental contaminants due to their wide-spread use as flame retardants. Their structural similarity to other halogenated organic pollutants, for example polychlorinated biphenyls (PCBs), has led to speculation that they may have similar toxicological properties and effects. Recent focus on PBDEs as possible priority pollutants has also led to an increasing need for reference standards of PBDEs for toxicological studies and for environmental analysis. In this work we synthesized a series of fluorinated PBDEs (F-PBDEs) which can be used as possible internal standards, as an alternative to high-cost alternatives, such as the (13)C-labelled analogues. F-PBDEs have been synthesized by using different coupling reactions and by bromination of fluorinated starting materials. 相似文献