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201.
Aleix Serrat‐Capdevila Juan B. Valdes Eugene Z. Stakhiv 《Journal of the American Water Resources Association》2014,50(2):509-525
This article is an assessment of the current state of the art and relative utility of satellite precipitation products (SPPs) for hydrologic applications to support water management decisions. We present a review of SPPs, their accuracy in diverse settings including the influence of geography, topography, and weather systems, as well as the pros and cons of their use for different water management applications. At the end of this broad synthesizing effort, recommendations are proposed for: (1) SPP developers to improve the quality, usability, and relevance of precipitation products; and (2) SPP users to improve the reliability of their predictions and hydrologic applications to better support water management. 相似文献
202.
Kirk R. Vincent Jonathan M. Friedman Eleanor R. Griffin 《Environmental management》2009,44(2):218-227
Removal of nonnative riparian trees is accelerating to conserve water and improve habitat for native species. Widespread control
of dominant species, however, can lead to unintended erosion. Helicopter herbicide application in 2003 along a 12-km reach
of the Rio Puerco, New Mexico, eliminated the target invasive species saltcedar (Tamarix spp.), which dominated the floodplain, as well as the native species sandbar willow (Salix exigua Nuttall), which occurred as a fringe along the channel. Herbicide application initiated a natural experiment testing the
importance of riparian vegetation for bank stability along this data-rich river. A flood three years later eroded about 680,000 m3 of sediment, increasing mean channel width of the sprayed reach by 84%. Erosion upstream and downstream from the sprayed
reach during this flood was inconsequential. Sand eroded from channel banks was transported an average of 5 km downstream
and deposited on the floodplain and channel bed. Although vegetation was killed across the floodplain in the sprayed reach,
erosion was almost entirely confined to the channel banks. The absence of dense, flexible woody stems on the banks reduced
drag on the flow, leading to high shear stress at the toe of the banks, fluvial erosion, bank undercutting, and mass failure.
The potential for increased erosion must be included in consideration of phreatophyte control projects. 相似文献
203.
B. Yang W.S. Shu Z.H. Ye R.L. Qiu G.X. Cui 《Environmental pollution (Barking, Essex : 1987)》2010,158(2):551-408
It is observed that ramie (Boehmeria nivea), an economic fiber crop, can establish and colonize metal-contaminated sites in China. Metal tolerance and accumulation by ramie originating from 13 metal-contaminated and 4 “clean” sites in China were compared under field and hydroponic conditions. All selected populations and germplasms displayed good growth performance under diverse metal-contaminated habitats; while growth responses, metal accumulation and tolerance were similar among the 8 populations and 2 germplasms when exposed to solutions containing elevated As, Cd, Pb, or Zn in the laboratory. These revealed that ramie possesses a certain degree of constitutional metal tolerance. To our knowledge, this is the first report of constitutional metal tolerance possessed by a fiber crop. Ramie can be considered as a good candidate for both fiber production and phytoremediation of sites contaminated by multi-metals, as it accumulates relative low metal concentrations, but possesses both high biomass and high economic value. 相似文献
204.
205.
John M. Skelly Jonathan A. Ferdinand James E. Savage Jeanne M. Jagodzinski James D. Mulik 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1280-1287
ABSTRACT Ogawa passive O3 samplers were used in a 13-week study (June 1-September 1, 1999) involving 11 forested and mountaintop sites in north-central Pennsylvania. Four of the sites were collocated with TECO model 49 O3 analyzers. A significant correlation (p < 0.0001) was found for 24-hr average weekly O3 concentrations between the two methodologies at the four sites with collocated monitors. As expected, there were positive relationships between increasing elevation of the sites and increasing O3 concentrations. No O3 exposure patterns were found on a west-to-east or south-to-north basis; however, the area known for lower O3 exposures within a smaller subsection of the study area showed consistently lower O3 exposures. Preliminary results regarding relationships of symptom responses within O3-sensitive bioindicators are also presented with black cherry (Prunus serotina, Elirli.) and common milkweed (Asclepias syriaca, L.) showing clear evidence of increasing injury with increasing O3 exposures. Due to the extremely dry conditions encountered in north-central Pennsylvania during the 1999 growing season, O3-induced symptoms were sporadic and quite delayed until late-season rains during the latter portion of the observation period. 相似文献
206.
In a single day, June 13, 1994, the total stock market capitalization of Exxon dropped by a full 5 percent, with news of the company's exposure to additional legal damages from the Exxon Valdez disaster. Despite what should have been a jarring wake-up call, however, Wall Street investors and company CEOs continue for the most part to conduct business as usual, unpersuaded that environmental considerations are anything more than a superficial and temporary blip on their Bloomberg screens. There is mounting evidence that they're dead wrong. In this article, the authors contend what they're currently sleeping through is nothing less than the beginnings of a profound, worldwide industrial restructuring. 相似文献
207.
The design of efficient water allocation systems depends, among other factors, on economic issues and, above all, on a reliable estimate of the economic value of water. In this paper the hedonic price method is utilized to reveal the implicit value of irrigation water by analyzing agricultural land values in Chalkidiki, a typical rural area in Greece. The method was applied to a sample of both irrigated and nonirrigated properties and the value of irrigation water was estimated by disaggregating the total price of each parcel of land, obtained through a local survey. Results show that, apart from typical value attributes, the agricultural characteristics of the land, including irrigation water availability, have a significant influence on land prices. 相似文献
208.
Assessment of Soil Cover Degradation and Desertification in Northern Lowland Dagestan 总被引:2,自引:0,他引:2
Stasyuk N. V. Dobrovol'skii G. V. Zalibekov Z. G. Saidov A. K. Dobrynin D. V. 《Russian Journal of Ecology》2004,35(3):144-149
New principles of the assessment of soil cover degradation and desertification, the scale and intensity of destructive processes manifestation are determined. 相似文献
209.
Prioritization for Conservation of Northern European Cattle Breeds Based on Analysis of Microsatellite Data 总被引:2,自引:0,他引:2
210.