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411.
Effects of Forest Management Practices on Mid-Atlantic Streams 总被引:1,自引:0,他引:1
Kent W. Thornton Shannon P. Holbrook Kenneth L. Stolte Ronald B. Landy 《Environmental monitoring and assessment》2000,63(1):31-41
Agricultural and urban land use activities have affected stream ecosystems throughout the mid-Atlantic region. However, over 60% of the mid-Atlantic region is forested. A study was conducted to investigate the effects of management practices on forested stream ecosystems throughout the mid-Atlantic region. The study consisted of two phases: Phase 1 was a literature synthesis of information available on the effects of forest management practices on stream hydrology, erosion and sedimentation, riparian habitat alteration, chemical addition, and change in biotic diversity in the mid-Atlantic region. In Phase 2, data from mid-Atlantic streams were analyzed to assess the effects of forest land use on stream quality at the regional scale. Typically, it is the larger order streams in which monitoring and assessment occurs—3rd order or higher streams. The impacts of forest management practices, particularly hydrologic modifications and riparian buffer zone alteration, occur predominantly in first and second order streams with cumulative impacts translating to higher order streams. Based on the literature review and mid-Atlantic Highland streams analysis, there are short-term (e.g., 2 to 5 years) effects of forest management practices on stream quality at local scales. However, signatures of cumulative effects from forest management practices are not apparent at regional scales in the Highlands. In general, forested land use is associated with good stream quality in the region compared with other land use practices. 相似文献
412.
Kent S. Murray Daniel T. Rogers 《Journal of Environmental Planning and Management》1999,42(6):801-810
An understanding of groundwater vulnerability in urban watersheds is important for the prevention of both surface water and groundwater contamination and can therefore be a useful tool in brownfield redevelopment and land use planning. Although industrial activity in southeastern Michigan has historically been restricted to the urbanized sections of metropolitan Detroit, new industrial development is rapidly taking place in rural and undeveloped areas. Although environmentalists and urban planners agree that industrial site recycling in urban centres (a.k.a. brownfield redevelopment) is preferable to developing green areas, many older sites remain undeveloped due to real and perceived risks. Using a PC-based geographic information system, a conceptual model of solute transport in soil was developed to evaluate potential impacts to both groundwater and surface water quality resulting from industrial development. The model was used to create a map of groundwater vulnerability within the Rouge River watershed of southeastern Michigan. The map has been used to pin-point several rural and undeveloped areas where groundwater quality is threatened by proposed development. It has also clearly demonstrated that many older brownfield sites, within the City of Detroit, are located on materials that have a much lower vulnerability to groundwater contamination and may therefore be far less costly to redevelop than greenfield sites in undeveloped areas of the watershed. 相似文献
413.
The dye malachite green (MG) is used worldwide as a fungicide in aquaculture. It is a toxic substance which in aqueous solutions is partly converted into its non-ionic colorless form (leucocarbinol). The equilibrium between these two forms is pH-dependent (pK = 6.9). To assess the photodegradation of MG under sunlight conditions, both species were irradiated separately in aqueous solutions with different pH values (4.0 and 12.0) using various ultraviolet and visible wavelength ranges (UV/VIS). A 700 W high-pressure mercury lamp with special filters was used. No artificial photooxidizers such as H2O2 or TiO2 were added. MG leucocarbinol proved to be much more sensitive to irradiation than the dye form. Quantum yields Φ were calculated for some wavelength ranges as follows: MG carbinol: Φ(280-312nm) is 4.3 × 10−3, Φ(313-410nm) is 5.8 × 10−3, and MG dye: Φ(280-312nm) is 4.8 × 10−5, Φ(313-365nm) is 1.1 × 10−5, and Φ(>365nm) is 0, respectively. Therefore, the solar photolysis of MG is an important sink and primarily depends on the photodegradation of the colorless leucocarbinol. During the irradiation of MG leucocarbinol with wavelengths >365 nm, an intermediate was formed which has photocatalytical properties. 相似文献
414.
P. Lasch M. Lindner B. Ebert M. Flechsig F.-W. Gerstengarbe F. Suckow P.C. Werner 《Environmental Modeling and Assessment》1999,4(4):273-286
A methodology for regional application of forest simulation models has been developed as part of an assessment of possible climate change impacts in the Federal state of Brandenburg (Germany). Here we report on the application of a forest gap model to analyse the impacts of climate change on species composition and productivity of natural and managed forests in Brandenburg using a statistical method for the development of climate scenarios. The forest model was linked to a GIS that includes soil and groundwater table maps, as well as gridded climate data with a resolution of 10 × 10 km and simulated a steady-state species composition which was classified into forest types based on the biomass distribution between species. Different climate scenarios were used to assess the sensitivity of species composition to climate change. The simulated forest distribution patterns for current climate were compared with a map of Potential Natural Vegetation (PNV) of Brandenburg.In order to analyse the possible consequences of climate change on forest management, we used forest inventory data to initialize the model with representative forest stands. Simulation experiments with two different management strategies indicated how forest management could respond to the projected impacts of climate change. The combination of regional analysis of natural forest dynamics under climate change with simulation experiments for managed forests outlines possible trends for the forest resources. The implications of the results are discussed, emphasizing the regional differences in environmental risks and the adaptation potentials of forestry in Brandenburg. 相似文献
415.
Urban water infrastructure expenditures cause a major financial burden to municipalities. In the opinion of many policy-makers, public funds may alleviate this burden and facilitate environmental policies. However, practice has shown that despite ambitious policies, funding often follows traditional cost-dominated thinking. In Austria, national policy-makers were interested in new guidelines for funding that increase the transparency of the planning, ensure the adequate treatment of ecological problems, and foster stakeholder involvement, but keep the process as simple as possible, and require minimal changes of the current guidelines. An interdisciplinary project team conducted such a study. Its outcome was tested in two pilot projects. Based on these experiences, policy-makers finally implemented the recommended guidelines for the funding of communal urban water infrastructure projects. A general observation about the policy-making process was a conservative attitude of policy-makers. They prefer simple constraints (precautionary principle) and flexible negotiations (delegation) to complex assessment and decision-aid methodologies. 相似文献
416.
Henner Hollert Sebastian Hudjetz Evelyn Claus Werner Manz Georg Reifferscheid Peter Heininger Jan Schwarzbauer Wolfgang Ahlf Thomas Braunbeck Werner Brack Tobias Schulze Andreas Sch?ffer und Hans-Toni Ratte 《Umweltwissenschaften und Schadstoff-Forschung》2009,21(3):235-237
Ohne Zusammenfassung
Verantwortliche Herausgeber: Jan Schwarzbauer · Peter Heininger · Evelyn Claus
相似文献
Henner Hollert (Corresponding author)Email: |
Evelyn ClausEmail: |
Peter HeiningerEmail: |
Jan SchwarzbauerEmail: |
417.
Benjamin S. Rashford Richard M. Adams JunJie Wu Richard A. Voldseth Glenn R. Guntenspergen Brett Werner W. Carter Johnson 《Regional Environmental Change》2016,16(2):515-526
Wetland productivity in the Prairie Pothole Region (PPR) of North America is closely linked to climate. A warmer and drier climate, as predicted, will negatively affect the productivity of PPR wetlands and the services they provide. The effect of climate change on wetland productivity, however, will not only depend on natural processes (e.g., evapotranspiration), but also on human responses. Agricultural land use, the predominant use in the PPR, is unlikely to remain static as climate change affects crop yields and prices. Land use in uplands surrounding wetlands will further affect wetland water budgets and hence wetland productivity. The net impact of climate change on wetland productivity will therefore depend on both the direct effects of climate change on wetlands and the indirect effects on upland land use. We examine the effect of climate change and land-use response on semipermanent wetland productivity by combining an economic model of agricultural land-use change with an ecological model of wetland dynamics. Our results suggest that the climate change scenarios evaluated are likely to have profound effects on land use in the North and South Dakota PPR, with wheat displacing other crops and pasture. The combined pressure of land-use and climate change significantly reduces wetland productivity. In a climate scenario with a +4 °C increase in temperature, our model predicts that almost the entire region may lack the wetland productivity necessary to support wetland-dependent species. 相似文献
418.
Rapid transport from the surface to wells in fractured rock: a unique infiltration tracer experiment
A unique infiltration tracer experiment was performed whereby a fluorescent dye was applied to the land surface in an agricultural field, near Perth, Ontario, Canada, to simulate the transport of solutes to two pumped monitoring wells drilled into the granitic gneiss aquifer. This experiment, interpreted using the discrete-fracture capability of the numerical model HydroGeoSphere, showed that solute transport from the surface through thin soil (less than 2m) to wells in fractured bedrock can be extremely rapid (on the order of hours). Also, it was demonstrated that maximum concentrations of contaminants originating from the ground surface will not necessarily be the highest in the shallow aquifer horizon. These are important considerations for both private and government-owned drinking water systems that draw water from shallow fractured bedrock aquifers. This research illustrates the extreme importance of protecting drinking water at the source. 相似文献
419.
Munier DJ Brittan KL Lanini WT 《Environmental science and pollution research international》2012,19(6):2281-2284
Introduction
Canola, which is genetically modified (GM) for tolerance to glyphosate, has the potential to become established as a new glyphosate resistant weed, thus reducing the effectiveness of glyphosate.Methods
Volunteer from dormant canola seeds produced thousands of plants per hectare in the fourth year (2011) following a 2007 crop harvest. This occurred with no additional canola seed production since the 2007 harvest.Results
Volunteer plants following harvests of annual crops are typically only a problem for the first year after harvest. In California, glyphosate is the core herbicide on over a million hectares of high value row, tree, and vine crops and new glyphosate resistant weeds reduce the effectiveness of glyphosate.Conclusions
The combination of dormant seed and herbicide resistance makes GM glyphosate-resistant canola a new and difficult California weed which was first observed in the winter of 2009. 相似文献420.
Triclosan—the forgotten priority substance? 总被引:1,自引:0,他引:1
von der Ohe PC Schmitt-Jansen M Slobodnik J Brack W 《Environmental science and pollution research international》2012,19(2):585-591