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1.
Governments need good information to design policies. However, inthe Argentine Pampas there are neither sufficient knowledge on environmental issues, nor clear perception of environmental alterations across space and time. The general objective of this work was to provide decision makers with a scientifically sound set of indicators aiming at the assessment of current status andfuture trends in the rural environment of this sensitiveregion. As driving criteria to select indicators, weassumed that they had to be sound, simple to calculate,easy to understand, and easily applicable by decision makers. They are related closely to significantecological structures and functions. Twelve basicindicators were identified: (1) land use, (2) fossil energyuse, (3) fossil energy use efficiency, (4) nitrogen (N)balance, (5) phosphorus (P) balance, (6) nitrogencontamination risk, (7) phosphorus contamination risk, (8) pesticide contamination, (9) soil erosion risk, (10) habitatintervention, (11) changes in soil carbon stock, and (12) balance of greenhouse gases. Indicators were geographicallyreferenced using a geographic information system (GIS). Thestrength of this study is not in the absolute value ofenvironmental indicators, but rather in theconceptualization of indicator and the identification ofchanging patterns, gradients and trends in space and time.According to our results, we can not definitely say thatagriculture in the Pampas, as a whole, tends to besustainable or not. While some indicators tend to improve,others keep stable, and the rest worsen. The relative importance among indicators must also be considered. The indicators that showed a negative net change are key to the identification of critical problems that will require special attention in the close future.  相似文献   

2.
Land take due to urbanization triggers a series of negative environmental impacts with direct effects on quality of life for people living in cities. Changes in ecosystem services are associated with land take, among which is the immediate C loss due to land use conversion. Land use change monitoring represents the first step in quantifying land take and its drivers and impacts. To this end, we propose an innovative methodology for monitoring land take and its effects on ecosystem services (in particular, C loss) under multi-scale contexts. The devised approach was tested in two areas with similar sizes, but different land take levels during the time-span 1990–2008 in Central Italy (the Province of Rome and the Molise Region). The estimates of total coverage of built up areas were calculated using point sampling. The area of the urban patches including each sampling point classified as built up areas in the year 1990 and/or in the year 2008 is used to estimate total abundance and average area of built up areas. Biophysical and economic values for carbon loss associated with land take were calculated using InVEST.Although land take was 7–8 times higher in the Province of Rome (from 15.1% in 1990 to 20.4% in 2008) than in Molise region, our findings show that its relative impact on C storage is higher in the latter, where the urban growth consistently affects not only croplands but also semi-natural land uses such as grasslands and other wooded lands. The total C loss due to land take has been estimated in 1.6 million Mg C, corresponding to almost 355 million €.Finally, the paper discusses the main characteristics of urban growth and their ecological impact leading to risks and challenges for future urban planning and land use policies.  相似文献   

3.
The purpose of this study is to investigate the land use intensity and land use change type at the basin scale in the middle and lower reaches of the Hanjiang River Basin (in Hubei Province, China) by combining the Landsat TM images in 1995 and 2000 with the land use database (in scale 1:10,000) and relative data. In this study, the basic data is acquired from the interpretation of remote sensing (RS) images. The intensity of land use and the rate of change in double-directions of land use dynamics are calculated with the support of software ARC/INFO. The intensity of land use is indicated by the intensity coefficient of land use, and the transition of land use types is quantified as the rate of change in double-direction of land use types and also expressed as the transition matrix of land use types. The results are expressed in space by Geographic Information System (GIS) software. Results of this study show that (1) the intensity of land use is high in the study region, the intensity coefficients of land use in 1995 and 2000 are 260.025 and 290.526, respectively, and the intensity of development and utilization of land is trend to increscent; and (2) the rate of land use change in double directions in the whole study region is 0.52 with great spatial variation and the differentiation of land use types. In the differentiation of land use types, the unutilized land (with the rate to 4.391) is developed fast, the grassland (with 2.836) and water area (with 1.664) are disturbed severely, and these changes will influence the eco-environment in the Hanjiang River Basin and all the Yangtze Basin. The rates of the farmland and the woodland are 0.424 and 0.344, respectively, meaning that the fundamentals of regional human-environmental system are relative stable. With this study, we can conclude that (1) the patterns of land use are increasingly changing in the study region, the environmental impacts are escalated on this stage, and the further outcomes are destined to change the stability of the regional human–environmental system; and (2) the most useful method to study the present land use and its change is through the use of the RS/GIS with the land use database (in scale 1:10,000).  相似文献   

4.
According to EC regulations the deliberate release of genetically modified (GM) crops into the agro-environment needs to be accompanied by environmental monitoring to detect potential adverse effects, e.g.unacceptable levels of gene flow from GM to non-GM crops, or adverse effects on single species or species groups thus reducing biodiversity. There is, however, considerable scientific and public debate on how GM crops should be monitored with sufficient accuracy, discussing questions of potential adverse effects, agro-environmental variables or indicators to be monitored and respective detection methods; Another basic component, the appropriate number and location of monitoring sites, is hardly considered. Currently, no consistent GM crop monitoring approach combines these components systematically. This study focuses on and integrates spatial agro-environmental aspects at a landscape level in order to design monitoring networks. Based on examples of environmental variables associated with the cropping of Bt-Maize (Zea maize L.), herbicide-tolerant (HT) winter oilseed rape (Brassica napus L.), HT sugar beet (Beta vulgaris L.), and starch-modified potato (Solanum tuberosum L.), we develop a transferable framework and assessment scheme that comprises anticipated adverse environmental effects, variables to be measured and monitoring methods.These we integrate with a rule-based GIS (geographic information system) analysis, applying widely available spatial area and point information from existing environmental networks. This is used todevelop scenarios with optimised regional GM crop monitoring networks.  相似文献   

5.
The aim of the present study was to monitor mouthpart deformities of Chironomus plumosus (Insecta-Diptera) in Lake Trasimeno (2000-2010) in relation with sediment contamination by heavy metals, which is one of the main causes of deformity induction. In Lake Trasimeno, concentrations of heavy metals in the investigated littoral zone were low, in comparison with those of the central area. By contrast, the incidence of deformities was much higher in the littoral station (2006-2009) than in the central area. In the littoral zone, the deformities progressively decreased and by 2010 reached values similar to those observed in the central area (2000-2002, 2010). This decrease was mainly due to the reduction of severe deformities, thus indicating an environmental quality recovery of this littoral sector. Chemical analysis revealed that the higher incidence of deformities in the littoral zone was not caused by heavy metal contamination, unless they may have contributed to a joint action with other toxicants. The present study on Lake Trasimeno provided additional evidence that chironomid mouthpart deformities can be used in biomonitoring programs to evaluate sediment contamination by toxicants. Since mouthpart deformities may also be induced by compounds not included in routine chemical analyses, they may better reflect sediment quality than chemical analysis alone.  相似文献   

6.
Large areas of public lands administered by the Bureau of Land Management and located in arid regions of the southwestern United States are being considered for the development of utility-scale solar energy facilities. Land-disturbing activities in these desert, alluvium-filled valleys have the potential to adversely affect the hydrologic and ecologic functions of ephemeral streams. Regulation and management of ephemeral streams typically falls under a spectrum of federal, state, and local programs, but scientifically based guidelines for protecting ephemeral streams with respect to land-development activities are largely nonexistent. This study developed an assessment approach for quantifying the sensitivity to land disturbance of ephemeral stream reaches located in proposed solar energy zones (SEZs). The ephemeral stream assessment approach used publicly-available geospatial data on hydrology, topography, surficial geology, and soil characteristics, as well as high-resolution aerial imagery. These datasets were used to inform a professional judgment-based score index of potential land disturbance impacts on selected critical functions of ephemeral streams, including flow and sediment conveyance, ecological habitat value, and groundwater recharge. The total sensitivity scores (sum of scores for the critical stream functions of flow and sediment conveyance, ecological habitats, and groundwater recharge) were used to identify highly sensitive stream reaches to inform decisions on developable areas in SEZs. Total sensitivity scores typically reflected the scores of the individual stream functions; some exceptions pertain to groundwater recharge and ecological habitats. The primary limitations of this assessment approach were the lack of high-resolution identification of ephemeral stream channels in the existing National Hydrography Dataset, and the lack of mechanistic processes describing potential impacts on ephemeral stream functions at the watershed scale. The primary strength of this assessment approach is that it allows watershed-scale planning for low-impact development in arid ecosystems; the qualitative scoring of potential impacts can also be adjusted to accommodate new geospatial data, and to allow for expert and stakeholder input into decisions regarding the identification and potential avoidance of highly sensitive stream reaches.  相似文献   

7.
8.
Reclaimed salt marshes are fragile environments where water salinization and accumulation of heavy metals can easily occur. This type of environment constitutes a large part of the Po River Delta (Italy), where intensive agricultural activities take place. Given the higher Ni background of Po River Delta soils and its water-soluble nature, the main aim of this contribution is to understand if reclamation can influence the Ni behavior over time. In this study, we investigated the geochemical features of 40 soils sampled in two different localities from the Po River Delta with different reclamation ages. Samples of salt marsh soils reclaimed in 1964 were taken from Valle del Mezzano while soils reclaimed in 1872 were taken nearby Codigoro town. Batch solubility tests and consecutive determination of Ni in pore-water were compared to bulk physicochemical compositions of soils. Bulk Ni content of the studied soils is naturally high, since these soils originated from Po River sediments derived from the erosion of ultramafic rocks. Moreover, it seems that Ni concentration increases during soil evolution, being probably related to the degradation of serpentine. Instead, the water-soluble Ni measured in the leaching tests is greater in soils recently reclaimed compared to the oldest soils. Soil properties of two soil profiles from a reclaimed wetland area were examined to determine soil evolution over one century. Following reclamation, pedogenic processes of the superficial horizons resulted in organic matter mineralization, pH buffer, and a decrease of Ni water solubility from recently to evolved reclaimed soil.  相似文献   

9.
10.
In the Mediterranean Region, habitat loss and fragmentation severely affect coastal wetlands, due to the rapid expansion of anthropogenic activities that has occurred in the last decades. Landscape metrics are commonly used to define landscape patterns and to evaluate fragmentation processes. This investigation focuses on the performance of a set of landscape pattern indices within landscapes characterized by coastal environments and extent below 1,000 ha. The aim is to assess the degree of habitat fragmentation for the monitoring of protected areas and to learn whether values of landscape metrics can characterize fine-resolution landscape patterns. The study areas are three coastal wetlands belonging to the Natura 2000 network and sited on the Adriatic side of Apulia (Southern Italy). The Habitat Maps were derived from the Vegetation Maps generated integrating phytosociological relevés and Earth Observation data. In the three sites, a total of 16 habitat types were detected. A selected set of landscape metrics was applied in order to investigate their performance in assessing fragmentation and spatial patterns of habitats. The final results showed that the most significant landscape patterns are related to highly specialized habitat types closely linked to coastal environments. In interpreting the landscape patterns of these highly specialized habitats, some specific ecological factors were taken into account. The shape indices were the most useful in assessing the degree of fragmentation of habitat types that usually have elongated morphology along the shoreline or the coastal lagoons. In all the cases, to be meaningful, data obtained from the application of the selected indices were jointly assessed, especially at the class level.  相似文献   

11.
The objective of the present study was to assess changes in land use/land cover patterns in the coastal town of Silivri, a part of greater Istanbul administratively. In the assessment, remotely sensed data, in the form of satellite images, and geographic information systems were used. Types of land use/land cover were designated as the percentage of the total area studied. Results calculated from the satellite data for land cover classification were compared successfully with the database Coordination of Information on the Environment (CORINE). This served as a reference to appraise the reliability of the study presented here. The CORINE Program was established by the European Commission to create a harmonized Geographical Information System on the state of the environment in the European Community. Unplanned urbanization is causing land use changes mainly in developing countries such as Turkey. This situation in Turkey is frequently observed in the city of Istanbul. There are only a few studies of land use–land cover changes which provide an integrated assessment of the biophysical and societal causes and consequences of environmental degradation in Istanbul. The research area comprised greater Silivri Town which is situated by the coast of Marmara Sea, and it is located approximately 60 km west of Istanbul. The city of Istanbul is one of the largest metropolises in Europe with ca. 15 million inhabitants. Additionally, greater Silivri is located near the terminal point of the state highway connecting Istanbul with Europe. Measuring of changes occurring in land use would help control future planning of settlements; hence, it is of importance for the Gretaer Silivri and Silivri Town. Following our evaluations, coastal zone of Silivri was classified into the land use groups of artificial surfaces agricultural areas and forests and seminatural areas with 47.1%, 12.66%, and 22.62%, respectively.  相似文献   

12.
Time-lapse resistivity measurements and groundwater geochemistry were used to study salinity effect on groundwater aquifer at the ex-promontory-land of Carey Island in Malaysia. Resistivity was measured by ABEM Terrameter SAS4000 and ES10-64 electrode selector. Relationship between earth resistivity and total dissolved solids (TDS) was derived, and with resistivity images, used to identify water types: fresh (ρ ( e ) > 6.5 Ω m), brackish (3 Ω m < ρ ( e ) < 6.5 Ω m), or saline (ρ ( e ) < 3 Ω m). Long-term monitoring of the studied area's groundwater quality via measurements of its time-lapse resistivity showed salinity changes in the island's groundwater aquifers not conforming to seawater-freshwater hydraulic gradient. In some aquifers far from the coast, saline water was dominant, while in some others, freshwater 30 m thick showed groundwater potential. Land transformation is believed to have changed the island's hydrogeology, which receives saltwater pressure all the time, limiting freshwater recharge to the groundwater system. The time-lapse resistivity measurements showed active salinity changes at resistivity-image bottom moving up the image for two seasons' (wet and dry) conditions. The salinity changes are believed to have been caused by incremental tide passing through highly porous material in the active-salinity-change area. The study's results were used to plan a strategy for sustainable groundwater exploration of the island.  相似文献   

13.
14.
Sulphide-bearing mine dumps are potential sources of pollution when acid mine drainage (AMD) occurs. Because the generation of AMD depends on the volume and composition of waste materials, their characterisation is crucial for the evaluation of geochemical hazards and for the design of remediation strategies to minimise their environmental impact. In this paper, a cost-effective strategy for the characterisation of an inactive mine dump in the Rio Marina mining district (Elba Island, Italy) using earth resistivity imaging (ERI) is presented. As no information regarding the nature of waste rocks is found in reports for the mine, five ERI profiles were acquired at the top of the waste pile. The results show that waste rocks are heterogeneous with a maximum thickness of 30 m. Due to the large amounts of dispersed sulphide minerals, the waste rocks are characterised by an electrically conductive geophysical signature in comparison to the surrounding resistive metamorphic bedrock. A geostatistical approach was adopted to estimate the elevation of the edges of the mine dump, and the net volume of the waste rocks was computed through a raster analysis of the elevations of the upper and lower boundaries of the mine dump. High-conductivity anomalies were detected within the core of the mine dump. The integration of the hydrogeological, geochemical and geological framework of the Rio Marina mining district suggests that these anomalies could be a geophysical signature of subsurface regions where AMD is currently generated or stored, thus representing sources of environmental pollution.  相似文献   

15.
Soil erosion is an open topic, not only because soil fertility is lost, but also because nutrients are spilled into water bodies, thereby causing pollution. Research carried out in this field has amply described this process, but the interaction between these factors is complex and experimental research is needed to understand the production of loads of nutrients for different land uses. This paper describes a long-term monitoring case study using high-resolution rainfall data and runoff samples, carried out in the Lake Vico basin (Central Italy) to determine the phosphorus (P) export during erosive rainfall events. State of the art GIS-based basin characterization and advanced rainfall-runoff models are employed in order to describe the relationship between nutrient export and rainfall or runoff time distribution. Results show that the phosphorus export is strongly related to such time distributions, and less to the cumulative amount of rainfall or runoff.  相似文献   

16.
Soils in urban parks are useful tracers of diffuse contamination and could represent a potential health risk for citizens. Soils in the parks of Torino, Italy, were sampled and analysed for a broad range of organic and inorganic contaminants. Concentrations of potentially toxic elements, PAHs, PCBs and polychlorinated dibenzo-p-dioxins and dibenzofurans were often above national legislation limits, and higher than surrounding rural areas or than other cities. Mean concentrations were 233 mg kg(-1) for Cr, 164 mg kg(-1) for Ni, 124 mg kg(-1) for Pb and 170 mg kg(-1) for Zn. Other inorganic contaminants such as Cd, As, and Hg showed high concentrations in some soils. Organic contaminants were also found to be enriched in the sampled parks (e.g. maximum concentrations of PCDDs/DFs and PCBs were 12.6 ng kg(-1) and 0.310 mg kg(-1), respectively). Data from this study reveal an important enrichment of parks for some contaminants, reflecting the intensity of phenomena of diffuse contamination. Historical parks presented the highest degree of contamination, suggesting that the age of soils rather than their proximity to sources of emissions is a key factor in determining soil contamination. Data obtained in this study could be of help in the investigation and remediation practices of urban contaminated sites within large cities.  相似文献   

17.
Heating, ventilation and air conditioning (HVAC) systems are a major source of energy consumption in buildings, directly and indirectly contributing to greenhouse gas (GHG) emissions. In the urban environment, and depending on local climatic conditions, air conditioning units attribute to these high energy demands. This study analyzes the use of residential air conditioning units and their associated global warming potential (GWP) between 2005 and 2030 for the city of Shenzhen, a fast-growing megacity located in Southern China. A life cycle assessment approach was adopted to quantify the GWP impacts which arise from both direct (refrigerant release) and indirect (energy consumption) sources, in combination with a materials flow analysis approach. The results show that the total GWP (expressed as carbon dioxide equivalents, CO2 eq.) from residential air conditioning systems increased from 2.2 ± 0.2 to 5.1 ± 0.4 million tonnes (Mt) CO2 eq. between 2005 and 2017, with energy consumption and refrigerant release contributing to 72.5% and 27.5% of the total demands, respectively. Immediate measures are required to restrict refrigerant release and reduce the energy consumption of air conditioning units, to help mitigate the predicted additional total emissions of 36.4 Mt. CO2 eq. potentially released between 2018 and 2030. This amount equals to approximately New Zealand's national CO2 emissions in 2017. The findings proposed in this study targets air conditioning units to reduce the GWP emissions in cities, and provide useful data references and insights for local authorities to incentivise measures for improving building energy efficiency management and performance.  相似文献   

18.
In this paper, various spatial modelling techniques were applied to analyse changes in soil cover and their impact on soil erosion in the Oplenac wine-producing area in Serbia in the past (1985 and 2013) and in the future (with predictions for 2041). The Integrated Valuation of Ecosystem Services and Trade-offs Sediment Delivery Ratio (InVEST SDR) model and the Modules for Land Use Change Evaluation (MOLUSCE) model, integrated with methods of remote sensing, were successfully applied and were shown to be valid tools for predicting the impact of Land Use Land Cover (LULC) changes when estimating soil loss. The results revealed that the greatest impact of land use changes between 1985 and 2013 was on a reduction in areas under vineyards and an extension of meadow and pasturelands as an individual and social response to economic conditions during the research period. The forecast for 2041 reflected the trends observed in the previous period, with the greatest changes witnessing an increase in urban areas and a decrease in areas of arable land. It was also found that the effect of LULC changes on spatio-temporal patterns in the Oplenac wine-producing area did not have a major impact on soil loss, meaning this area, with its good agro-climatic characteristics, is suitable for the intensification of agricultural production.  相似文献   

19.
20.
This article sets out to analyse how and to what degree land use is linked to the physical characteristics of the territory itself, and the way in which changes in land use are determined by agricultural and socio-demographic dynamics. The study was conducted within the territorial boundaries of five municipalities surrounding Lake Trasimeno and refers to the periods 1977–2000 for land use and 1971–2001 for socio-demography data. The use of environmental, social, economic and agricultural indicators demonstrates how a mix of various indicators are useful for monitoring the changes which took place. It also shows the powerful influence that socio-demographic factors exert upon land use and landscape change.  相似文献   

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