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1.
The analysis of data of the ground-level ozone concentration and accumulated ozone exposure over a threshold of 40 ppb (AOT40) in the rural areas of Lithuania is presented. Trends in the annual ozone mean, 95{th} and 25{th} percentiles were determined as statistically not significant at Preila and Rugsteliskes sites during the 1994hbox{–}2004 period. Trends in the ozone concentration and its percentiles in the air masses arriving to Preila station in “polluted” and “unpolluted” sectors have been examined. Statistically significant changes in the ozone annual mean and 25th percentile were found in air masses in both “polluted” and “unpolluted” sectors in the 1988hbox{–}2002 period. The trend analysis in the ozone monthly mean and percentiles for each month of the year revealed the main changes in the ozone level in both sectors during January-May. Insignificant downward trends in monthly 95th percentile in “unpolluted” sector and upward trends in “polluted” sector were found during summer months. Values of AOT40 for the protection of forests as well as crops and semi-natural vegetation were determined during the 1994–2004 period. The estimated AOT40 values for the protection of forests were lower than the critical level at Lithuanian rural sites but AOT40 values for the protection of crops and semi-natural vegetation were found to be higher than the critical level at both sites.  相似文献   

2.
This paper introduces a new portable intelligent electronic nose system developed especially for measuring and analysing livestock and poultry farm odours. It can be used in both laboratory and field. The sensor array of the proposed electronic nose consists of 14 gas sensors, a humidity sensor, and a temperature sensor. The gas sensors were especially selected for the main compounds from the livestock farm odours. An expert system called “Odour Expert” was developed to support researchers’ and farmers’ decision making on odour control strategies for livestock and poultry operations. “Odour Expert” utilises several advanced artificial intelligence technologies tailored to livestock and poultry farm odours. It can provide more advanced odour analysis than existing commercially available products. In addition, a rank of odour generation factors is provided, which refines the focus of odour control research. Field experiments were conducted downwind from the barns on 14 livestock and poultry farms. Experimental results show that the predicted odour strengths by the electronic nose yield higher consistency in comparison to the perceived odour intensity by human panel. The “Odour Expert” is a useful tool for assisting farmers’ odour management practises. Supported by Ontario Pork, Natural Sciences and Engineering Research Council (NSERC), and Ontario Ministry of Agriculture and Food (OMAF) of Canada.  相似文献   

3.
In the study, we analyze and assess quantitatively the spatial pattern of vegetation and its ecological degradation information in the Honghe National Nature Reserve (HNNR), a Ramsar-designated site in Northeast China. Statistics from historical survey data are used to measure the degradation of marshes over time and changes in the hydrological regime. Long-term statistical data are also employed to analyze both natural and human impacts on these changes. Both the wetland degradation model and its mechanisms are discussed in this paper. The research finds that the loss of water and other types of degradation in the vegetation habitat caused by the rapid deterioration of the hydrological regime has threatened the status of HNNR as a “storage area of natural genes.” Scientifically constructed strategies are urgently required to ensure sustainable economic benefits that do not adversely affect this nature reserve.  相似文献   

4.
Bioassays as well as biochemical responses (biomarkers) in ecosystems due to environmental stress provide us with signals (environmentally signalling) of potential damage in the environment. If these responses are perceived in this early stage in ecosystems, the eventual damage can be prevented. Once ecosystem damage has occurred, the remedial action processes for recovery could be expensive and pose certain logistical problems. Ideally, “early warning signals” in ecosystems using sensing systems of biochemical responses (biomarkers) would not only tell us the initial levels of damage, but these signals will also provide us with answers by the development of control strategies and precautionary measures in respect to the European Water Framework Directive (WFD). Clear technical guidelines or technical specifications on monitoring are necessary to establish and characterise reference conditions for use in an ecological status classification system for surface water bodies. For the Ecotoxicological Risk Assessment (ERA) of endocrine effects we used an approach of the exposure – dose – response concept. Based on the “Ecototoxicological Classification System of Sediments” that uses pT-values to classify effects in different river systems, we transferred the bio-monitoring data to the five-level ecological system of the WFD. To understand the complexity of the structure of populations and processes behind the health of populations, communities and ecosystems an ERA should establish links between natural factors, chemicals, and biological responses so as to assess causality. So, our ecological monitoring assessment has incorporated exposure & effects data.  相似文献   

5.
The present study aims at creating an evaluation system for the quality of running waters, based on the analysis of benthic macroinvertebrate records from Hellenic rivers (473 samples from 8 river basins). The proposed evaluation system (Hellenic Evaluation Score and its Interpretation Index) may be used for waters sampled with the cost effective semi-quantitative sampling method of “3 min kick-sweep” and requires benthic macroinvertebrates to be identified to the taxonomic level of family. Though resulting from a modification of the Spanish score BMWP, it differs from it in the following characteristics: a) it includes the relative abundance of benthic macroinvertebrates and b) it takes into consideration the habitat diversity of the studied site, classifying it as “poor” or “rich”, based on some parameters of the System B of the Water Framework Directive (2000/60/EU). Its interpretation is also based on a five-scaled classification system, consistent with the provisions of the same Directive.  相似文献   

6.
Kemaliye (Erzincan/Turkey) is the member of European Association of Historic Towns and Regions. The aim of this study was to reveal the visual richness of the town; to identify the relationship between landscape spatial pattern and visual quality of the landscape and to offer some suggestions for the future planning in regarding to these visual beauties. The visual quality assessment method was used in this study. The results of the study revealed three landscape types that have the highest visual quality. Among those, the highest one is urban scenery 3 (US3; VQP = 5.9400), the second is geological structure scenery 5 (GSS 5; VQP = 5.9200) and the third natural scenery 3 (NS3; VQP = 5.9133). Visual quality assessment showed that urban pattern, geological structure and natural resources of the region also have visual value. The relationships between landscape spatial pattern and visual quality of landscape indicated that certain characteristics of landscape affected the quality. For instance, as the texture level decreased in natural landscapes and as the green areas increased in geological structure, visual preferences ratio increased. Some suggestions were also made regarding the visual resources use in the region.  相似文献   

7.
Green development is the fundamental way for high-quality development of marine economy. Achievement of green development goals of marine economy depends on the local government's decision-making preferences and reasonable marine-related environmental regulatory instruments. Based on 2007–2016 panel data of China's coastal provinces, this paper adopts the differential GMM(Gaussian Mixture Model) model to empirically analyze the impact of government preferences and environmental regulations on green development of marine economy. The results indicate that: lag exists in the promotion of environmental regulation on green development of marine economy.The impact of government preferences varies, in which, industrial preferences have a negative effect on green development of marine economy,while environmental preferences have a positive effect.The joint action of industrial preference and environmental preference inhibits green development of marine economy, while that of environmental preference and environmental regulation plays a promotion role. Different government preferences indicate different impacts in different regions. Environmental preference promotes the green development of marine economy in the Bohai Bay region, while industrial preference suppresses it. Both industrial preference and environmental preference in the Yangtze River Delta region have promotion effect, while only environmental preference in the Pan-Pearl River Delta region does so. Therefore, the government should establish a more complete official examination system, improve the marine environmental regulation system, and formulate differentiated green development policies for marine economy.  相似文献   

8.
Acadia National Park was one of the 14 sites included in the Park Research and Intensive Monitoring of Ecosystems network (PRIMENet). For eight years the EPA monitored ultraviolet (UV) radiation at this site, with the National Park Service (NPS) sponsoring a total climate and air monitoring station. Under the auspices of PRIMENet, research projects were initiated that investigated the effects of UV on amphibians, determined watershed mass balances, and developed a model of deposition along an elevational gradient. The monitoring data and research results have been used by park management to protect vegetation and water resources from ozone and deposition. These data are now being used to develop a “vital signs” monitoring program under the NPS’ Inventory and Monitoring Program. These data sets have been used in regional, national and international programs to protect human health and resources from air pollution. Public outreach has been accomplished through web site resources and via the Schoodic Education and Research Center.  相似文献   

9.
The concentrations of hexachlorocyclohexanes (HCHs) were investigated in urban soil samples collected from business area, classical garden (CL), culture and educational area, large public green space (LA), residential area, and roadside area in Beijing. HCH concentrations ranged from 0.32 to 136.43 ng/g, with a geometric mean of 3.46 ng/g. The HCH concentrations in CL and LA were much higher than that in the other types of land use, which was due to the usage of HCHs to protect vegetation in CL and LA. Source identification showed that contamination source of HCHs was derived from historical HCHs (including technical HCHs and Lindane) as well as the long-range atmospheric transportation of HCHs. HCH concentrations showed a decreasing trend from the city centre to the suburb, and it increased with the age of the urban area. HCHs were negatively correlated with pH and positively correlated with total organic carbon and black carbon in soils. Health risk assessment with CalTOX and Monte Carlo analysis showed that health risks mainly came from dermal uptake and inhalation exposure pathways, and the total risk values were lower than the acceptable health risk value (10 − 6). The sensitivity analysis indicated that the reaction half-life of HCHs in soil, fraction dermal uptake from soil, exposure duration, and organic carbon fraction in soil significantly contributed to the variance of the health risk.  相似文献   

10.
Participatory Integrated Assessment (PIA) is an approach which aims at developing methods which allow to combine evaluations of experts and lay people in the field of Integrated Assessment. Thus, policy recommendations derived from PIA exercises are informed by scientific judgments and by valuations of “non-scientists”. For any PIA methodology the provision of insights, facts and figures about the policy problem at hand is crucial. In this paper we describe a PIA methodology which combines the social science research instrument “focus group” with a specific computer information tool, the “Personal CO2 Calculator” (PCC). The tool supports citizens in discussing and recommending measures on climate change policy. Based on our experiences, we plead for information instruments that are tuned to and assist concrete target groups with their specific interests. This helps that policy recommendations derived from PIA exercises are based on both scientific knowledge as well as citizens' and stakeholders' policy preferences. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

11.
Although satellite radar altimetry was developed and optimized for open oceans, it has been used to monitor variations in the level of inland water-bodies such as lakes and rivers. Here, for the first time, we have further used the altimetry-derived variation of water level for estimating the fluctuation of water storage as an addition to the present in situ water storage estimation systems to be used in remote areas and in emergency situation such as in the events flooding monitoring and for studying the effect of climate change. Lake Dongting, the second largest lake in China, influenced frequently by flooding, was, therefore, chosen to demonstrate the potential of the technique. By using the concept of an “assumed reference point”, we converted Topex/Poseidon satellite altimetry data on water level variations in Lake Dongting to “water level” data. The “water level” time-series data and in situ water storage were used to establish a rating curve. From the rating curve, we converted data on “water level” derived from seven years (1993–1999) of Topex/Poseidon data to actual water storage in Lake Dongting. The result reveals that the seasonal and annual fluctuations of water storage occurred during the 1990s with a more frequent flooding at the late 1990s' especially the flooding in whole catchment level in 1998 and 1999. The study supports the usefulness of satellite altimetry for dense and continuous monitoring of the temporal variations in water dynamic in moderate to large lakes.  相似文献   

12.
Integrated Environmental Assessment (IEA) can be loosely defined as policy‐relevant, multidisciplinary research on environmental issues. Many, diverse activities in this broad field are ongoing, but the approaches lack the structure, standardization and quality control common in disciplinary research. IEA has three stages: “structuring the problem”, “analyzing the problem” and “communicating the findings and insights”. Each stage has its inherent difficulties, not least because problem definition and analysis are neither separable nor unambiguous nor unique. Difficulties are exacerbated in the first and third stages by the necessity for science and policy to work together. Difficulties are exacerbated in the second stage by the necessity of different scientific disciplines to cooperate. The European Forum on Integrated Environmental Assessment is an initiative to improve scientific quality and policy‐relevance of IEA, by organizing two series of workshops, one looking in detail at current and desired scientific practices, the other reviewing current and establishing further applications of IEA to environmental issues in Europe. This revised version was published online in July 2006 with corrections to the Cover Date. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
Various natural hazards such as landslides, avalanches, floods and debris flows can result in enormous property damages and human casualties in Eastern Black Sea region of Turkey. Mountainous topographic character and high frequency of heavy rain are the main factors for landslide occurrence in Ardesen, Rize. For this reason, the main target of the present study is to evaluate the landslide hazards using a sequence of historical aerial photographs in Ardesen (Rize), Turkey, by Photogrammetry and Geographical Information System (GIS). Landslide locations in the study area were identified by interpretation of aerial photographs dated in 1973 and 2002, and by field surveys. In the study, the selected factors conditioning landslides are lithology, slope gradient, slope aspect, vegetation cover, land class, climate, rainfall and proximity to roads. These factors were considered as effective on the occurrence of landslides. The areas under landslide threat were analyzed and mapped considering the landslide conditioning factors. Some of the conditioning factors were investigated and estimated by employing visual interpretation of aerial photos and topographic data. The results showed that the slope, lithology, terrain roughness, proximity to roads, and the cover type played important roles on landslide occurrence. The results also showed that degree of landslides was affected by the number of houses constructed in the region. As a consequence, the method employed in the study provides important benefits for landslide hazard mitigation efforts, because a combination of both photogrammetric techniques and GIS is presented.  相似文献   

14.
Termite mounds are abundant components of Tummalapalle area of uranium mineralization of Cuddapah District of Andhra Pradesh, India. The systematic research has been carried out on the application of termite mound sampling to mineral exploration in this region. The distribution of chemical elements Cu, Pb, Zn, Ni, Co, Cr, Li, Rb, Sr, Ba, and U were studied both in termite soils and adjacent surface soils. Uranium accumulations were noticed in seven termite mounds ranging from 10 to 36 ppm. A biogeochemical parameter called “Biological Absorption Coefficient” of the termite mounds indicated the termite affected soils contained huge amounts of chemical elements than the adjacent soils.  相似文献   

15.
Magnetic susceptibility (κ) is an easily detectable geophysical parameter that can be used as a proxy or semi-quantitative tracer of atmospheric industrial and urban dusts deposited in topsoil. An enhanced κ value of topsoil is in many cases also associated with high concentrations of soil pollutants (mostly heavy metals). High-resolution magnetic screening of topsoil in areas of high pollution influx is a useful tool for detection of pollution “hot spots”. General and regional screening maps with a grid density of 10 or 5 km have been performed on the basis of forest topsoil measurement only. The purpose of this study was to perform high-resolution magnetic screening with different grid densities in both forested and agricultural areas (arable land). Our large study area (ca. 200 km2) was located in a relatively more polluted region of the central part of Upper Silesia, and a second (small) one (ca. 100 m2) was located in the western part of Upper Silesia, with considerably lower influx of pollution. In the framework of this study, we applied a statistical comparison of data obtained in forested areas and on arable land. The arable soil showed statistically significantly lower κ values, the result of “physical dilution” of the arable layer caused by annual ploughing. Thus arable soils must be avoided during high-resolution field measurement. From semivariograms, it was clear that the spatial correlations in forest topsoil are much stronger than in arable soil, which suggests that a denser measurement grid is required in forested areas.  相似文献   

16.
In this paper, the following key issues are addressed: the so-called “South” – the Group of 77 and China – and how to engage their interest and commitment; the purported savings if the flexible mechanisms are availed of, and the macro-economic impacts of meeting the Kyoto objectives; the associated issues of narrowing the extent and scope for such trading by setting a limit on how much can be traded, and “hot air” – the surplus quota above their own projected needs which Russia and most of the old Soviet Union have to offer; operational issues, including units to be traded, monitoring and enforcement, allocation of permits, competitiveness and risk management; in the case of emissions trading, the initial allocation of permits. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
The Environmental Protection Agency (EPA) has made available on the worldwide web a systematic stream stressor identification procedure, the “Causal Analysis/Diagnosis Decision Information System” or CADDIS. We report here the results of a survey of regulators and scientists in 11 states who use CADDIS or another stressor identification procedure in their work. The 13 survey questions address guidelines as to what impairment scenarios to approach with stressor identification, what information is needed to perform stressor identification, and what the stakeholder role is in performing stressor identification. At the time of this survey (the summer of 2009), the EPA CADDIS website was less commonly used among the state regulators surveyed than the published EPA stressor identification document on which it is based. The respondents generally find the EPA stressor identification procedure useful and capable of being adapted to their individual needs. Survey respondents all use stressor identification in their Total Maximum Daily Load work, but also in a wide variety of other applications. All the “types of evidence” included in the CADDIS stressor identification procedure are used by the practitioners surveyed with the exception of the results of ecological simulation models. While the CADDIS documentation encourages the involvement of stakeholders in stressor identification, most respondents do not assemble stakeholder teams of local officials and citizens to participate in stressor analyses.  相似文献   

18.
Starting from the basic assumption of the syndrome concept that essentially all of the present problematic civilization–nature interactions on the global scale can be subdivided into a limited number of typical patterns, the analysis of the response of these patterns (syndromes) to climate change can make a major contribution to climate impact research, surmounting the difficulties of more common sectoral ceteris paribus impact studies with respect to their systemic integration. In this paper we investigate in particular the influence of climate on the regional proneness or disposition towards one of the most important syndromes with respect to famines and malnutrition, the Sahel Syndrome. It describes the closely interlinked natural and socioeconomic aspects of rural poverty driven degradation of soil and vegetation on marginal sites. Two strategies of global climate impact assessment on a spatial 0.5°×0.5° grid were pursued: (a) As a measure for the climate sensitivity of the regional proneness, the absolute value of the gradient of the disposition with respect to the global field of 3} 12 monthy normals of temperature, irradiation and precipitation is calculated. (b) The disposition was evaluated for two different climate forecasts under doubled atmospheric CO2 concentration. For both strategies two new quantitative global models were incorporated in a fuzzy-logic-based algorithm for determining the disposition towards the Sahel Syndrome: a neural-net-based model for plant productivity and a waterbalance model which calculates surface runoff considering vertical and lateral fluxes, both driven by the set of 36 monthly climatological normals and designed to allow very fast global numerical evaluation.Calculation (b) shows that the change in disposition towards the Sahel Syndrome crucially depends on the chosen climate forecast, indicating that the disagreement of climate forecasts is propagated to the impact assessment of the investigated socio-economic pattern. On the other hand the regions with a significant increase in disposition in at least one of the climate scenario-based model runs form a subset of the regions which are indicated by the local climate sensitivity study (a) as highly sensitive – illustrating that the gradient measure applied here provides a resonable way to calculate an upper limit or worst case of negative climate impact. This method is particularly valuable in the case of uncertain climate predictions as, e.g., for the change in precipitation patterns.  相似文献   

19.
Towards a Formal Framework of Vulnerability to Climate Change   总被引:7,自引:0,他引:7  
There is confusion regarding the notion of “vulnerability” in the climate change scientific community. Recent research has identified a need for formalisation, which would support accurate communication and the elimination of misunderstandings that result from the use of ambiguous terminology. Moreover, a formal framework of vulnerability is a prerequisite for computational approaches to its assessment. This paper presents an attempt at developing such a formal framework. We see vulnerability as a relative concept in the sense that accurate statements about vulnerability are possible only if one clearly specifies (1) the entity that is vulnerable, (2) the stimulus to which it is vulnerable and (3) the preference criteria to evaluate the outcome of the interaction between the entity and the stimulus. We relate the resulting framework to the Intergovernmental Panel on Climate Change conceptualisation of vulnerability and two recent vulnerability studies. This paper is dedicated to the memory of Gerhard Petschel-Held, whose pioneering work on syndromes of global change has been a source of inspiration for us and for others across various schools of thought on vulnerability.  相似文献   

20.
A sub-surface desert water harvester was constructed in the sagebrush steppe habitat of south-central Idaho, U.S.A. The desert water harvester utilizes a buried micro-catchment and three buried storage tanks to augment water for wildlife during the dry season. In this region, mean annual precipitation (MAP) ranges between about 150–250 mm (6″–10″), 70% of which falls during the cold season, November to May. Mid-summer through early autumn, June through October, is the dry portion of the year. During this period, the sub-surface water harvester provides supplemental water for wildlife for 30–90 days, depending upon the precipitation that year. The desert water harvester is constructed with commonly available, “over the counter” materials. The micro-catchment is made of a square-shaped, 20 mL. “PERMALON” polyethylene pond liner (approximately 22.9 m × 22.9 m = 523 m2) buried at a depth of about 60 cm. A PVC pipe connects the harvester with two storage tanks and a drinking trough. The total capacity of the water harvester is about 4777 L (1262 U.S. gallons) which includes three underground storage tanks, a trough and pipes. The drinking trough is refined with an access ramp for birds and small animals. The technology is simple, cheap, and durable and can be adapted to other uses, e.g. drip irrigation, short-term water for small livestock, poultry farming etc. The desert water harvester can be used to concentrate and collect water from precipitation and run-off in semi-arid and arid regions. Water harvested in such a relatively small area will not impact the ground water table but it should help to grow small areas of crops or vegetables to aid villagers in self-sufficiency.  相似文献   

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