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671.
Leal Filho W 《Journal of environmental monitoring : JEM》2008,10(11):1261-1264
Public awareness about the problems related to rainforest depletion increased considerably in the 1990s, but the level of emphasis to the problems faced by the world's tropical rainforests has become conspicuously low in recent years. Yet, there is a heightened sense of urgency in respect of the need to handle the challenges posed by climate change and the role that rainforest depletion may play in this process. This paper reviews the relationships between rainforest depletion and climate change, and outlines some areas where action is needed. 相似文献
672.
Walter Veselka IV James S. Rentch William N. Grafton Walter S. Kordek James T. Anderson 《Environmental monitoring and assessment》2010,170(1-4):555-569
Bioassessment methods for wetlands, and other bodies of water, have been developed worldwide to measure and quantify changes in “biological integrity.” These assessments are based on a classification system, meant to ensure appropriate comparisons between wetland types. Using a local site-specific disturbance gradient, we built vegetation indices of biological integrity (Veg-IBIs) based on two commonly used wetland classification systems in the USA: One based on vegetative structure and the other based on a wetland’s position in a landscape and sources of water. The resulting class-specific Veg-IBIs were comprised of 1–5 metrics that varied in their sensitivity to the disturbance gradient (R 2?=?0.14???0.65). Moreover, the sensitivity to the disturbance gradient increased as metrics from each of the two classification schemes were combined (added). Using this information to monitor natural and created wetlands will help natural resource managers track changes in biological integrity of wetlands in response to anthropogenic disturbance and allows the use of vegetative communities to set ecological performance standards for mitigation banks. 相似文献
673.
Davi Gasparini Fernandes Cunha Maria do Carmo Calijuri Walter Kennedy Dodds 《Environmental monitoring and assessment》2014,186(2):1143-1155
Reservoirs are artificial ecosystems with physical, chemical, and biological transitional characteristics between rivers and lakes. Greater water retention time in reservoirs provides conditions for cycling materials inputs from upstream waters through sedimentation, biological assimilation and other biogeochemical processes. We investigated the effects of reservoirs on the water quantity and quality in the Great Plains (Kansas, USA), an area where little is known about these dominant hydrologic features. We analyzed a 30-year time-series of discharge, total phosphorus (TP), nitrate (NO3 ?), and total suspended solids (TSS) from six reservoirs and estimated overall removal efficiencies from upstream to downstream, testing correlations among retention, discharge, and time. In general, mean removal of TP (42–74 %), TSS (0–93 %), and NO3 ? (11–56 %) from upstream to downstream did not change over 30 years. TP retention was associated with TSS removal, suggesting that nutrient substantial portion of P was adsorbed to solids. Our results indicated that reservoirs had the effect of lowering variance in the water quality parameters and that these reservoirs are not getting more or less nutrient-rich over time. We found no evidence of temporal changes in the yearly mean upstream and downstream discharges. The ratio upstream/downstream discharge was analyzed because it allowed us to assess how much contribution of additional unsampled tributaries may have biased our ability to calculate retention. Nutrient and sediment removal was less affected by hydraulic residence time than expected. Our study demonstrates that reservoirs can play a role in the removal and processing of nutrient and sediments, which has repercussions when valuing their ecological services and designing watershed management plans. 相似文献
674.
Walter Veselka IV James T. Anderson Walter S. Kordek 《Environmental monitoring and assessment》2010,164(1-4):533-548
Considerable resources are being used to develop and implement bioassessment methods for wetlands to ensure that “biological integrity” is maintained under the United States Clean Water Act. Previous research has demonstrated that avian composition is susceptible to human impairments at multiple spatial scales. Using a site-specific disturbance gradient, we built avian wetland indices of biological integrity (AW-IBI) specific to two wetland classification schemes, one based on vegetative structure and the other based on the wetland’s position in the landscape and sources of water. The resulting class-specific AW-IBI was comprised of one to four metrics that varied in their sensitivity to the disturbance gradient. Some of these metrics were specific to only one of the classification schemes, whereas others could discriminate varying levels of disturbance regardless of classification scheme. Overall, all of the derived biological indices specific to the vegetative structure-based classes of wetlands had a significant relation with the disturbance gradient; however, the biological index derived for floodplain wetlands exhibited a more consistent response to a local disturbance gradient. We suspect that the consistency of this response is due to the inherent nature of the connectivity of available habitat in floodplain wetlands. 相似文献
675.
Walter Joe Jacumin Lyman A. Ripperton 《Journal of the Air & Waste Management Association (1995)》2013,63(3):96-97
A procedure is described for producing a sulfur dioxide (SO2) contaminated atmosphere within a body plethysmograph, exposing man to this atmosphere while maintaining the SO2 concentration at a given level, and measuring the concentration with less than a oneminute lag time. A syringe is used to introduce incremental volumes of SO2 limiting the maximum SO2 concentration in the chamber and assuring safety of the subject. A Titrilog SO2 analyzer with its rapid response characteristics provides quick measurement of the SO2 concentration. The body plethysmograph used in this manner serves simultaneously as a pulmonary function measuring device and as an exposure chamber. 相似文献
676.
Walter G. England Lynn H. Teuscher R. Bruce Snyder 《Journal of the Air & Waste Management Association (1995)》2013,63(10):986-989
An experimental program was undertaken in December 1974, for the Portland General Electric Company (PGE) to ascertain the plume configurations resulting from the operations of the Beaver Gas Turbine Facility at Port Westward, OR. The experimental program consisted of: airborne measurements of NOX to determine the plume (s) configuration and a meteorological field program to determine atmospheric stabilities and wind profiles during the field program. This note reports on the plume measurement portion of the program only. 相似文献
677.
John A. Dunning Walter W. Heck 《Journal of the Air & Waste Management Association (1995)》2013,63(9):882-886
Pinto bean (Phaseolus vulgaris, L.) and Bel W3 tobacco (Nicotiana tabacum, L.) were grown and exposed to 40 pphm ozone for 1 hr under a range of light intensities, temperatures, and relative humidities. Foliar injury to the more sensitive plant leaves was determined on the third day after exposure. Each atmospheric factor was independently assessed. Two significant three-way interactions were found: exposure light intensity by growth light intensity by species, and growth temperature by exposure temperature by species. Three significant two-way interactions were found for humidity: growth humidity by exposure humidity, growth humidity by species, and exposure humidity by species. The sensitivity of each species to ozone changed with changes in each environmental condition. 相似文献
678.
Michael G. Johnston Walter H. Stevenson 《Journal of the Air & Waste Management Association (1995)》2013,63(6):932-935
The EPA proposed regulations for municipal waste combustors (MWCs) on December 20, 1989. The regulations include (1) performance standards under Section lll(b) of the Clean Air Act (CAA) for new, modified, or reconstructed MWCs and (2) draft emission guidelines and compliance schedules for the states to use to develop control requirements from existing MWCs under Section 111(d). This paper will outline the proposed air emission standards and guidelines, as well as the basis for the prescribed emission limits. The schedule for the remainder of the regulations development will also be discussed. 相似文献
679.
680.
Gast n Azziz Mat as Gim nez H ctor Romero Patricia M. Valdespino-Castillo Luisa I. Falc n Lucas A. M. Ruberto Walter P. Mac Cormack Silvia Batista 《Frontiers of Environmental Science & Engineering》2019,13(3):44