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1.
Protecting water quality in forested regions is increasingly important as pressures from land-use, long-range transport of air pollutants, and climate change intensify. Maintaining forest industry without jeopardizing sustainability of surface water quality therefore requires new tools and approaches. Here, we show how forest management can be optimized by incorporating landscape sensitivity and hydrological connectivity into a framework that promotes the protection of water quality. We discuss how this approach can be operationalized into a hydromapping tool to support forestry operations that minimize water quality impacts. We specifically focus on how hydromapping can be used to support three fundamental aspects of land management planning including how to (i) locate areas where different forestry practices can be conducted with minimal water quality impact; (ii) guide the off-road driving of forestry machines to minimize soil damage; and (iii) optimize the design of riparian buffer zones. While this work has a boreal perspective, these concepts and approaches have broad-scale applicability.  相似文献   

2.
The water footprint by the Water Footprint Network (WF) is an ambitious tool for measuring human appropriation and promoting sustainable use of fresh water. Using recent case studies and examples from water-abundant Fennoscandia, we consider whether it is an appropriate tool for evaluating the water use of forestry and forest-based products. We show that aggregating catchment level water consumption over a product life cycle does not consider fresh water as a renewable resource and is inconsistent with the principles of the hydrologic cycle. Currently, the WF assumes that all evapotranspiration (ET) from forests is a human appropriation of water although ET from managed forests in Fennoscandia is indistinguishable from that of unmanaged forests. We suggest that ET should not be included in the water footprint of rain-fed forestry and forest-based products. Tools for sustainable water management should always contextualize water use and water impacts with local water availability and environmental sensitivity.  相似文献   

3.
Many organizations and their consultants are involved in sampling programs to characterize waste streams and materials at industrial facilities. Due to financial limitations, calendar deadlines, or other practical restrictions, a short-term, survey-type sampling plan (“sampling survey”) may need to he implemented. Survey results can he used to determine if the wastes are hazardous or if they are being managed in accordance with applicable regulations. This paper brings together practical experience and diverse information to identify the major concerns in conducting sampling surveys and to suggest methods of approaching these concerns. The paper addresses sampling in time and space, “correct” sampling to minimize bias, selecting equipment to minimize contamination, sample handling, and quality assurance/quality control. Even a quick sampling survey can be a high quality effort with a careful approach to the critical issues.  相似文献   

4.
Mounting research highlights the contribution of ecosystem services provided by urban forests to quality of life in cities, yet these services are rarely explicitly considered in environmental policy targets. We quantify regulating services provided by urban forests and evaluate their contribution to comply with policy targets of air quality and climate change mitigation in the municipality of Barcelona, Spain. We apply the i-Tree Eco model to quantify in biophysical and monetary terms the ecosystem services “air purification,” “global climate regulation,” and the ecosystem disservice “air pollution” associated with biogenic emissions. Our results show that the contribution of urban forests regulating services to abate pollution is substantial in absolute terms, yet modest when compared to overall city levels of air pollution and GHG emissions. We conclude that in order to be effective, green infrastructure-based efforts to offset urban pollution at the municipal level have to be coordinated with territorial policies at broader spatial scales.  相似文献   

5.
A quantitative single-particle analytical technique, called low-Z particle electron probe X-ray microanalysis, combined with the utilization of their morphological information on individual particles, was applied to characterize six aerosol samples collected in one Korean city, Incheon, during March 9–15, 2006. The collected supermicron aerosol particles were classified based on their chemical species and morphology on a single-particle basis. Many different particle types were identified and their emission source, transport, and reactivity in the air were elucidated. In the samples, particles in the “soil-derived particles” group were the most abundant, followed by “reacted sea-salts”, “reacted CaCO3-containing particles”, “genuine sea-salts”, “reacted sea-salts + others”, “Fe-containing particles”, “anthropogenic organics”, (NH4)2SO4, “K-containing particles”, and “fly ash”. The application of this single-particle analysis, fully utilizing their chemical compositional and morphological data of individual particles, clearly revealed the different characteristics of the six aerosol samples. For samples S3 and S5, which were sampled during two Asian dust storm events, almost all particles were of soil origin that had not experienced chemical modification and that did not entrain sea-salts during their long-range transport. For sample S1, collected at an episodic period of high PM10 concentration and haze, anthropogenic, secondary, and soil-derived particles emitted from local sources were predominant. For samples S2, S4, and S6, which were collected on average spring days with respect to their PM10 concentrations, marine originated particles were the most abundant. Sample S2 seems to have been strongly influenced by emissions from the Yellow Sea and Korean peninsula, sample S4 had the minimum anthropogenic influence among the four samples collected in the absence of any Asian dust storm event, and sample S6 seems to have entrained air pollutants that had been transported from mainland China over the Yellow Sea to Korea.  相似文献   

6.
Making defensible risk-based decisions is a complex process that incorporates risk assessment into a risk management framework. Many site investigations require additional study, negotiations and/or actions for arsenic detected in soil samples, in many cases where no process related sources are identified and no other chemicals of concern are identified. Regulatory agencies develop guidance to standardize approaches to risk-based site investigations that focus on achieving “safe” concentrations. For arsenic, the action level is frequently in the “gray region”, a U.S. Environmental Protection Agency (USEPA) term associated with a region of high uncertainty for risk management decisions in the “decision performance curve” associated with the data quality objective (DQO) process. Recognizing the conservative nature of the risk-based screening value for arsenic, approaches to enforce this level (or proof of comparability to natural background) may have numerous consequences including ineffective use of resources, stigmas on properties or actions at industrial or hazardous sites that are inconsistent with their regional setting. Florida has developed regulations and guidance on investigation of brownfield sites and has supported a study by the University of Florida (UF) to evaluate natural background concentrations in Florida soils. This paper discusses the sources of uncertainty near the soil cleanup target levels (SCTLs) in the Florida decision-making framework.  相似文献   

7.
The increasing role of chemistry in industrial production and its direct and indirect impacts in everyday life create the need for continuous search and efficiency improvement of new methods for decomposition/removal of different classes of waterborne anthropogenic pollutants. This review paper addresses a highly promising class of water treatment solutions, aimed at tackling the pressing problem of emerging contaminants in natural and drinking waters and wastewater discharges. Radiation processing, a technology originating from radiation chemistry studies, has shown encouraging results in the treatment of (mainly) organic water pollution. Radiation (“high energy”) processing is an additive-free technology using short-lived reactive species formed by the radiolysis of water, both oxidative and reducing, to carry out decomposition of organic pollutants. The paper illustrates the basic principles of radiolytic treatment of organic pollutants in water and wastewaters and specifically of one of its most practical implementations (electron beam processing). Application examples, highlighting the technology’s strong points and operational conditions are described, and a discussion on the possible future of this technology follows.  相似文献   

8.
Freer-Smith P  Carnus JM 《Ambio》2008,37(4):254-262
The loss of forest area globally due to change of land use, the importance of forests in the conservation of biodiversity and in carbon and other biogeochemical cycles, together with the threat to forests from pollution and from the impacts of climate change, place forestry policy and practice at the center of global environmental and sustainability strategy. Forests provide important economic, environmental, social, and cultural benefits, so that in forestry, as in other areas of environmental policy and management, there are tensions between economic development and environmental protection. In this article we review the current information on global forest cover and condition, examine the international processes that relate to forest protection and to sustainable forest management, and look at the main forest certification schemes. We consider the link between the international processes and certification schemes and also their combined effectiveness. We conclude that in some regions of the world neither mechanism is achieving forest protection, while in others local or regional implementation is occurring and is having a significant impact. Choice of certification scheme and implementation of management standards are often influenced by a consideration of the associated costs, and there are some major issues over the monitoring of agreed actions and of the criteria and indicators of sustainability. There are currently a number of initiatives seeking to improve the operation of the international forestry framework (e.g., The Montreal Process, the Ministerial Convention of the Protection of Forests in Europe and European Union actions in Europe, the African Timber Organisation and International Tropical Timber Organisation initiative for African tropical forest, and the development of a worldwide voluntary agreement on forestry in the United Nations Forum on Forests). We suggest that there is a need to improve the connections between scientific understanding, policy development, and forestry practice, and also the cooperation between the various international initiatives and processes, so that the international framework is more effective and its influence is extended geographically.  相似文献   

9.
Tunisia has very limited potential of surface and groundwater resources which are subject to different quantitative and qualitative forms of degradation. The risk of groundwater pollution results from the interaction between the vulnerability of aquifers to pollution and anthropogenic activities. Our research focuses on the study of the Sers water table water quality (northwest Tunisia) following the inputs used for agricultural activities in the region. Water samples were extracted from 40 wells to analyze the main physicochemical parameter indicators of the groundwater quality. The results obtained show that these waters have two major facies: Na-Cl and Ca-Mg-SO4. The nitrate contents are relatively high suggesting that the agricultural activities are probably the most important anthropogenic source of water contamination. The results of the Standardized Principal Component Analysis (SPCA) confirm the geochemical methods and results and provide further information about the water quality of the Sers El Kef aquifer. In addition, the pollution degree differs from one site to another depending on the spreading rate of nitrogen fertilizers and the distance from the pollution source.  相似文献   

10.
Nitrogen (N) availability plays multiple roles in the boreal landscape, as a limiting nutrient to forest growth, determinant of terrestrial biodiversity, and agent of eutrophication in aquatic ecosystems. We review existing research on forest N dynamics in northern landscapes and address the effects of management and environmental change on internal cycling and export. Current research foci include resolving the nutritional importance of different N forms to trees and establishing how tree–mycorrhizal relationships influence N limitation. In addition, understanding how forest responses to external N inputs are mediated by above- and belowground ecosystem compartments remains an important challenge. Finally, forestry generates a mosaic of successional patches in managed forest landscapes, with differing levels of N input, biological demand, and hydrological loss. The balance among these processes influences the temporal patterns of stream water chemistry and the long-term viability of forest growth. Ultimately, managing forests to keep pace with increasing demands for biomass production, while minimizing environmental degradation, will require multi-scale and interdisciplinary perspectives on landscape N dynamics.  相似文献   

11.
Carbon stock dynamics was monitored in the Uttara Kannada district, Western Ghats, India, for ten years on eight one-hectare sampling areas belonging to different management and forest categories. The study was initiated in 1984 and the area was monitored until 1994. Our study indicates that, in general, the carbon stock has enhanced during the study period with an average growth of 1.008 t/ha/year. However, there were differences in carbon stocks in different management regimes. The minor forests that are subjected to intense human pressures had a negative growth rate, i.e. 0.237 t/ha/year, while the reserve forests have a carbon assimilation rate of 1.31 t/ha/year. This indicates that human pressure has certainly decreased the carbon accumulation in the forests of Uttara Kannada. Despite the anthropogenic pressure, the minor forests have higher carbon accumulation through recruits as compared to the reserve forests. Thus it is suggested that a management strategy is needed to look into enhancing recruitment patterns in the minor forests which would become future carbon stocks.  相似文献   

12.
One of the key aspects introduced by the European Water Framework Directive 2000/60/EC (WFD) and developed by Groundwater Directive 2006/118/EC was the need to analyse pollution trends in groundwater bodies in order to meet the environmental objectives set in Article 4 WFD. According to this Directive, the main goal of “good status” should be achieved by the year 2015, and having reached this horizon, now is a suitable time to assess the changes that have taken place with the progressive implementation of the WFD. An extensive database is available for the Guadalhorce River basin, and this was used not only to identify in groundwater but also to draw real conclusions with respect to the degree of success in meeting the targets established for this main deadline (2015) The geographic and climate context of the Guadalhorce basin has facilitated the development of a variety of economic activities, but the one affecting the largest surface area is agriculture (which is practised on over 50 % of the river basin). The main environmental impacts identified in the basin aquifers arise from the widespread use of fertilisers and manures, together with the input of sewage from population centres. In consequence, some of the groundwater bodies located in the basin have historically had very high nitrate concentrations, often exceeding 200 mg/L. In addition, return flows, the use of fertilisers and other pressures promote the entry of other pollutants into the groundwater, as well as the salinisation of the main aquifers in the basin. In order to assess the hydrochemical changes that have taken place since the entry into force of the WFD, we performed a detailed trends analysis, based on data from the official sampling networks. In some cases, over 35 years of water quality data are available, but these statistics also present significant limitations, due to some deficiencies in the design or management; thus, data are missing for many years, the results are subject to seasonality effects, there are gaps in the historical records obtained by the monitoring networks and other shortcomings. The results obtained were analysed with the non-parametric Mann-Kendall test and revealed a general upward trend of pollutants in the areas affected by major pressures. In this analysis, we evaluated not only the increase or decrease in pollutants but also the different processes detected and the sources of pollution within the basin area. Our evaluation shows that robust measures should be taken in order to prevent further major degradation of groundwater quality and to enable “good quality” status to be achieved in future extensions of the WFD.  相似文献   

13.
The Expansion of Farm-Based Plantation Forestry in Vietnam   总被引:2,自引:0,他引:2  
This study targets plantation forestry by farm households (small holders), which is increasing globally and most rapidly in China and Vietnam. By use of an interdisciplinary approach on three study sites in Vietnam, we examined the trends in farmers’ tree planting over time, the various pre-requisites for farm-based plantation forestry and its impact on rural people’s livelihood strategies, socio-economic status, income and security. The findings indicated a change from subsistence to cash-based household economy, diversification of farmers’ incomes and a transformation of the landscape from mainly natural forests, via deforestation and shifting cultivation, to a landscape dominated by farm-based plantations. The trend of transformation, over a period of some 30 years, towards cash crops and forestry was induced by a combination of policy, market, institutional, infrastructural and other conditions and the existence of professional farming communities, and was most rapid close to the industrial market.  相似文献   

14.
Recent years have seen considerable improvement in water quality standards (QS) for metals by taking account of the effect of local water chemistry conditions on their bioavailability. We describe preliminary efforts to further refine water quality standards, by taking account of the composition of the local ecological community (the ultimate protection objective) in addition to bioavailability. Relevance of QS to the local ecological community is critical as it is important to minimise instances where quality classification using QS does not reconcile with a quality classification based on an assessment of the composition of the local ecology (e.g. using benthic macroinvertebrate quality assessment metrics such as River InVertebrate Prediction and Classification System (RIVPACS)), particularly where ecology is assessed to be at good or better status, whilst chemical quality is determined to be failing relevant standards. The alternative approach outlined here describes a method to derive a site-specific species sensitivity distribution (SSD) based on the ecological community which is expected to be present at the site in the absence of anthropogenic pressures (reference conditions). The method combines a conventional laboratory ecotoxicity dataset normalised for bioavailability with field measurements of the response of benthic macroinvertebrate abundance to chemical exposure. Site-specific QSref are then derived from the 5%ile of this SSD. Using this method, site QSref have been derived for zinc in an area impacted by historic mining activities. Application of QSref can result in greater agreement between chemical and ecological metrics of environmental quality compared with the use of either conventional (QScon) or bioavailability-based QS (QSbio). In addition to zinc, the approach is likely to be applicable to other metals and possibly other types of chemical stressors (e.g. pesticides). However, the methodology for deriving site-specific targets requires additional development and validation before they can be robustly applied during surface water classification.  相似文献   

15.
The physicochemical properties and the contamination levels of mercury and arsenic in roadway dust from Baoji, NW China were investigated using an Atomic Fluorescence Spectrophotometer. Contamination levels were assessed based on the geoaccumulation index and the enrichment factor. The results show that magnetic susceptibilities of roadway dust were higher than Holocene loess–soil of central Shaanxi Loess Plateau. The mean contents of organic matter, PM10 and PM100 were 8.8%, 21.8% and 98.6%, respectively. Mercury concentration ranged from 0.48 to 2.32 μg g?1, with a mean value of 1.11 μg g?1, 17.1 times the Chinese soil mercury background value and 37 times the Shaanxi soil mercury background value. Arsenic concentration ranged from 9.0 to 42.8 μg g?1, with a mean value of 19.8 μg g?1, 1.8 times the Chinese and Shaanxi soil arsenic background values. The geoaccumlation index and enrichment factor indicate that mercury in the dust mainly originated from anthropogenic sources with ratings of “strongly polluted” and “strongly to extremely polluted”, whereas arsenic in dust originated from both natural and anthropogenic sources, with a ratings of “moderately to strongly polluted” and “strongly polluted”. Industrial activities, such as a coal-fired power station, coke-oven plant, and cement manufacturing plant, augmented by vehicular traffic, are the anthropogenic sources of mercury and arsenic in the roadway dust.  相似文献   

16.
Gases and particulate matter predictions from the UCD/CIT air quality model were used in a visibility model to predict source contributions to visual impairment in the San Joaquin Valley (SJV), the southern portion of California's Central Valley, during December 2000 and January 2001. Within the SJV, daytime (0800–1700 PST) light extinction was dominated by scattering associated with airborne particles. Measured daytime particle scattering coefficients were compared to predicted values at approximately 40 locations across the SJV after correction for the increased temperature and decreased relative humidity produced by “smart heaters” placed upstream of nephelometers. Mean fractional bias and mean fractional error were ?0.22 and 0.65, respectively, indicating reasonable agreement between model predictions and measurements. Particulate water, nitrate, organic matter, and ammonium were the major particulate species contributing to light scattering in the SJV. Daytime light extinction in the SJV averaged between December 25, 2000 and January 7, 2001 was mainly associated with animal ammonia sources (28%), diesel engines (18%), catalyst gasoline engines (9%), other anthropogenic sources (9%), and wood smoke (7%) with initial and boundary conditions accounting for 13%. The source apportionment results from this study apply to wintertime conditions when airborne particulate matter concentrations are typically at their annual maximum. Further study would be required to quantify source contributions to light extinction in other seasons.  相似文献   

17.
A field-based evaluation of the biological effects of potential nickel (Ni) exposures was conducted using monitoring data for benthic macroinvertebrates and water chemistry parameters for streams in England and Wales. Observed benthic community metrics were compared to expected community metrics under reference conditions using RIVPACS III+?software. In order to evaluate relationships between Ni concentrations and benthic community metrics, bioavailable Ni concentrations were also calculated for each site. A limiting effect from Ni on the 90th percentile of the maximum achievable ecological quality was derived at “bioavailable Ni” exposures of 10.3 μg l?1. As snails have been identified as particularly sensitive to nickel exposure, snail abundance in the field in response to nickel exposure, relative to reference conditions, was also analysed. A “low effects” threshold for snail abundance based on an average of spring and autumn data was derived as 3.9 μg l?1 bioavailable Ni. There was no apparent effect of Ni exposure on the abundance of Ephemeroptera (mayflies), Plecoptera (stoneflies) or Tricoptera (caddisflies) when expressed relative to a reference condition within the range of “bioavailable Ni” exposures observed within the dataset. Nickel exposure concentrations co-vary with the concentrations of other stressors in the dataset, and high concentrations of Ni are also associated with elevated concentrations of other contaminants.  相似文献   

18.
For many national parks and wilderness areas with special air quality protections (Class I areas) in the western United States (U.S.), wildfire smoke and dust events can have a large impact on visibility. The U.S. Environmental Protection Agency’s (EPA) 1999 Regional Haze Rule used the 20% haziest days to track visibility changes over time even if they are dominated by smoke or dust. Visibility on the 20% haziest days has remained constant or degraded over the last 16 yr at some Class I areas despite widespread emission reductions from anthropogenic sources. To better track visibility changes specifically associated with anthropogenic pollution sources rather than natural sources, the EPA has revised the Regional Haze Rule to track visibility on the 20% most anthropogenically impaired (hereafter, most impaired) days rather than the haziest days. To support the implementation of this revised requirement, the EPA has proposed (but not finalized) a recommended metric for characterizing the anthropogenic and natural portions of the daily extinction budget at each site. This metric selects the 20% most impaired days based on these portions using a “delta deciview” approach to quantify the deciview scale impact of anthropogenic light extinction. Using this metric, sulfate and nitrate make up the majority of the anthropogenic extinction in 2015 on these days, with natural extinction largely made up of organic carbon mass in the eastern U.S. and a combination of organic carbon mass, dust components, and sea salt in the western U.S. For sites in the western U.S., the seasonality of days selected as the 20% most impaired is different than the seasonality of the 20% haziest days, with many more winter and spring days selected. Applying this new metric to the 2000–2015 period across sites representing Class I areas results in substantial changes in the calculated visibility trend for the northern Rockies and southwest U.S., but little change for the eastern U.S.

Implications: Changing the approach for tracking visibility in the Regional Haze Rule allows the EPA, states, and the public to track visibility on days when reductions in anthropogenic emissions have the greatest potential to improve the view. The calculations involved with the recommended metric can be incorporated into the routine IMPROVE (Interagency Monitoring of Protected Visual Environments) data processing, enabling rapid analysis of current and future visibility trends. Natural visibility conditions are important in the calculations for the recommended metric, necessitating the need for additional analysis and potential refinement of their values.  相似文献   


19.
Deterioration in groundwater quality has attracted wide social interest in China. In this study, groundwater quality was monitored during December 2014 at 115 sites in the Hutuo River alluvial-pluvial fan region of northern China. Results showed that 21.7% of NO3 ? and 51.3% of total hardness samples exceeded grade III of the national quality standards for Chinese groundwater. In addition, results of gray relationship analysis (GRA) show that 64.3, 10.4, 21.7, and 3.6% of samples were within the I, II, IV, and V grades of groundwater in the Hutuo River region, respectively. The poor water quality in the study region is due to intense anthropogenic activities as well as aquifer vulnerability to contamination. Results of principal component analysis (PCA) revealed three major factors: (1) domestic wastewater and agricultural runoff pollution (anthropogenic activities), (2) water-rock interactions (natural processes), and (3) industrial wastewater pollution (anthropogenic activities). Using PCA and absolute principal component scores-multivariate linear regression (APCS-MLR), results show that domestic wastewater and agricultural runoff are the main sources of groundwater pollution in the Hutuo River alluvial-pluvial fan area. Thus, the most appropriate methods to prevent groundwater quality degradation are to improve capacities for wastewater treatment and to optimize fertilization strategies.  相似文献   

20.
Boreal forests in Sweden are exploited in a number of ways, including forestry and reindeer husbandry. In the winter, reindeer feed mainly on lichens, and lichen-rich forests are a key resource in the herding system. Commercial forestry has mainly negative effects on reindeer husbandry, and conflicts between these two industries have escalated over the last century. This article reviews the effects of modern forest management practices on the winter resources available for reindeer husbandry. Forestry affects reindeer husbandry at both the stand level and the landscape level and over various time scales. Clear-cutting, site preparation, fertilization, short rotation times, and forest fragmentation have largely resulted in a reduced amount of ground growing and arboreal lichens and restricted access to resource. This article also discusses alternative forestry practices and approaches that could reduce the impacts of forestry on reindeer husbandry, both in the short and long term.  相似文献   

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