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11.
A statistical methodology formulated for defining background or baseline levels of constituents of concern in groundwater is presented. The methodology was developed for the case where prior delineation of unimpacted areas is not possible because of site history and a large set of groundwater monitoring measurements exists. Consideration was given to spatial and temporal trends, outliers, and final segregation of wells into impacted or unimpacted categories to develop probability distributions and summary statistics for each constituent evaluated. The formulated approaches were applied to groundwater monitoring data for the U.S. Department of Energy Savannah River Site facility, and results for four representative constituents (aluminum, arsenic, mercury, and tritium) are discussed.  相似文献   
12.
Mehta, Vikram M., Norman J. Rosenberg, and Katherin Mendoza, 2011. Simulated Impacts of Three Decadal Climate Variability Phenomena on Water Yields in the Missouri River Basin. Journal of the American Water Resources Association (JAWRA) 47(1):126‐135. DOI: 10.1111/j.1752‐1688.2010.00496.x Abstract: The Missouri River Basin (MRB) is the largest river basin in the United States (U.S.), and is one of the most important crop and livestock‐producing regions in the world. In a previous study of associations between decadal climate variability (DCV) phenomena and hydro‐meteorological (HM) variability in the MRB, it was found that positive and negative phases of the Pacific Decadal Oscillation (PDO), the tropical Atlantic sea‐surface temperature gradient variability (TAG), and the west Pacific warm pool (WPWP) temperature variability were significantly associated with decadal variability in precipitation and 2‐meter air temperature in the MRB, with combinations of various phases of these DCV phenomena associated with drought, flood, or neutral HM conditions. Here, we report on a methodology developed and applied to assess whether the aforementioned DCVs directly affect the hydrology of the MRB. The Hydrologic Unit Model of the U.S. (HUMUS) was used to simulate water yields in response to realistic values of the PDO, TAG, and WPWP at 75 widely distributed, eight‐digit hydrologic unit areas within the MRB. HUMUS driven by HM anomalies in both the positive and negative phases of the PDO and TAG resulted in major impacts on water yields, as much as ±20% of average water yield in some locations. Impacts of the WPWP were smaller. The combined and cumulative effects of these DCV phenomena on the MRB HM and water availability can be dramatic with important consequences for the MRB.  相似文献   
13.
Soil samples were collected with distance at 5, 20, 40, 80, 160 and 320 m from the Shen-Ha Highway, Northeast China, to investigate the effect of heavy metals of highway origin on soil nematode guilds. The contents of soil Pb, Cu and Zn and the nematode community structure in this investigation were analyzed. The results showed that the contents of total and available Pb, Cu and Zn varied significantly with the different distances from the highway. Pb was the main pollutant in the soils in the vicinity of Shen-Ha Highway and the zone from 20 to 40 m away from the highway was the most polluted area. The highest abundance of soil nematodes was found at 5 m while the lowest at 20 m away from the highway. Thirty six genera of nematodes belonging to 23 families were identified. Nematode guilds having different responses to soil heavy metals were classified into four types. Soil nematode guilds may act as a prominent indicator to heavy metal pollution of highway origin.  相似文献   
14.
Amyotrophic lateral sclerosis (ALS), a progressive disorder that usually runs a fatal course within 2–5 years of onset, is characterized by loss of motor neurons in the cortex, brain stem, and spinal cord. In this study mercury (Hg) concentrations were determined in blood samples of 40 ALS patients, of whom 24 ALS patients were from the Ganga plain region and their metal levels were found to be significantly higher. In contrast, Hg levels in the 16 ALS patients from non-Ganga plain regions whose levels were similar to those of the control subjects. Mercury in stream water samples and freshly deposited stream sediment were determined in the locations of patients’ native residences along the Ganga plain region and metal levels were found to be higher than the threshold guideline values for Hg in stream waters recommended by WHO. The geo-accumulation index in selected sites of freshly deposited stream sediment ranged from moderate to highly polluted. The high levels of Hg observed in ALS patients may potentially alter the redox status of neuronal cell components and induce cell-death pathways.  相似文献   
15.
Animals in the Himalayan region are reared basically to supplement the family income and sustain crop production, and constitute an important component of the rural economy of the region. Given the ecological importance of the livestock production system in terms of intrinsic values as a life support system for local people and a contribution towards sustainable agriculture through its role in the maintenance of soil fertility, the present study was conducted. This paper describes and assesses the current status of livestock production systems, monetary input/output, status of available forest resources, current level of pressure on the livestock production system and recommends strategies for sustainable development of a livestock production system in the Rawain Valley of Central Himalaya.  相似文献   
16.
The seasonal effects of untreated and treated municipal sewage on the nutrients-nitrate (NO(3)), phosphate (PO(4)), sulphate (SO(4)), and the biochemical oxygen demand (BOD), chemical oxygen demand (COD) and dissolved oxygen (DO) of the receiving urban canal, the Buckingham canal at Kalpakkam (Tamil Nadu, India) was monitored monthly during pre- monsoon-2005 to post-monsoon-2006. The NO(3), PO(4) and SO(4) contents were higher in the downstream than that of the upstream of the outfall points of treated as well as untreated sewage, of the canal. The NO(3) and PO(4) contents were higher during summer than that of monsoon; however the SO(4) was higher during winter and lower during summer in the canal water. The BOD and COD were lower and DO was higher at the upstream than that of downstream of the canal. The concentrations of BOD and COD were higher during summer season, which decreased during monsoon season, while the DO decreased during the summer season and increased in monsoon season in the canal water. Cluster analysis applied to the six sampling points of the canal, has grouped them based on the water quality similarities.  相似文献   
17.
A large section of the population (70%) of Uttarakhand largely depends upon agricultural based activities for their livelihood. Rural community of the mountains has developed several indigenous and traditional methods of farming to conserve the crop diversity and rejoice agrodiversity with religious and cultural vehemence. Traditional food items are prepared during occasion, festivals, weddings, and other religious rituals from diversified agrodiversity are a mean to maintain agrodiversity in the agriculture system. Agrodiversity is an insurance against disease and extreme climatic fluctuations, as a coping mechanism in times of scarcity, as a means to enhance overall productivity of farms, as a source of critical nutrition and medicine in the Himalayan region. The different traditional system of agriculture and indigenous method of maintaining soil fertility, socio-cultural and religious rituals has saved many crops that are under threatened category. But all these system and practices are ignored nauseatingly in hill agriculture policy, where more emphasis was given for plain areas. Less emphasis is being put on local systems that rely on existing natural, human, and social assets such as biodiversity, traditional knowledge, and social capital underpinning collective action to ensure food security. Of late, development planners have realized the importance of appropriate technologies and therefore have stressed the need for on-site training, and capacity building of user groups in rural areas of the region. Rural technology demonstration and training center have been supposed as a means disseminating technologies enabling improvement in the yield potential of farms, income generation from off-farm activities, and conservation and efficient use of natural resources. There is a strong need to bring desirable changes in the agricultural policy, research, and development in reference to mountainous regions. The present paper describe present scenario of agriculture, traditional, and socio-cultural practices of retaining soil fertility and agrodiversity, policy dimensions, and strategies for management of the Himalayan agroecosystems.  相似文献   
18.
Cellulose micro/nanofibrils were successfully extracted from softwood Douglas fir in three distinct stages. Initially raw Douglas fir wood chips were subjected to a hot water extraction (HWE) treatment. Then HWE treated cellulosic fibers underwent a bleaching process followed by a mild ultrasonication. Chemical composition analysis according to ASTM standards confirmed that most of hemicelluloses and nearly all lignin were removed during the first two stages, respectively. Microscopy studies showed formation of nanofibrils during the ultrasonication process, and increasing ultrasonication time led to generation of greater percentage of nanofibrils. With the removal of the matrix materials, the crystallinity of the cellulosic fibers was increased, whereas thermal stability was maintained. HWE opened up the cell wall structure, thereby facilitating the subsequent fractionation into micro/nanofibrils. The obtained cellulose micro/nanofibrils could serve as reinforcing material in composite products or raw material for other applications, such as filtration membrane.  相似文献   
19.
Traditional crop diversity and landraces in agricultural land use in Himalaya have great significant for long-term sustainability of agroecosystems, together with conservation and management of the surrounding landscape. Traditional crop varieties and races, which evolved over time through trial and error, not only provide basic nutritional requirements, but also food security. Loss of crop biodiversity has taken place over recent years, principally and inadvertently related to changing lifestyle, growing demand for cash crops in regional markets and burgeoning apple farming, whose acreage has increased with a concomitant decline in area under traditional crops. For sustainable landscape development, on-farm conservation of traditional crop diversity is urgently needed. An empirical study was done to understand the causes and consequences of declines in crop biodiversity and production, effect of apple farming on traditional crops and changing lifestyles of traditional people.  相似文献   
20.
Determining the factors that affect male mating success is essential to understanding how sexual selection operates, including explanations of the adaptive value of female preferences and how variation in male traits is maintained in a population. Although females may appear to choose males based on a single parameter, female mate choice is often a complex series of assessments of male quality that can only be revealed through manipulation of multiple male traits. In the moth Utetheisa ornatrix (Lepidoptera: Arctiidae), females have been shown to judge males primarily on their production of a courtship pheromone, hydroxydanaidal, derived from defensive chemicals acquired as larvae. Recent work, however, suggested that other factors, including prior mating experience by males, may also influence the outcome of precopulatory interactions with females. I ran mating trials with one female and two males to determine whether there were any differences in male mating success based on their prior exposure to females, mating experience, and time between matings. Previously mated males were favored over virgins when both males lacked the pheromone, but courting experience and mating interval did not explain these differences in male mating success. Furthermore, multiply mated males lacking the pheromone were favored over virgin males that produced the pheromone, thus reversing the commonly observed trend of female precopulatory bias towards males with higher levels of the pheromone. These results demonstrate that males with mating experience can secure copulations despite deficiencies in the pheromone, and I provide possible mechanisms and discuss their implications regarding sexual selection.  相似文献   
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