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991.
Phosphor imager autoradiography is a technique for rapid, sensitive analysis of the localization of xenobiotics in plant tissues. Use of this technique is relatively new to research in the field of plant science, and the potential for enhancing visualization and understanding of plant uptake and transport of xenobiotics remains largely untapped. Phosphor imager autoradiography is used to investigate the uptake and translocation of the explosives 1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene within Populus deltoides × nigra DN34 (poplar) and Panicum vigratum Alamo (switchgrass). In both plant types, TNT and/or TNT-metabolites remain predominantly in root tissues while RDX and/or RDX-metabolites are readily translocated to leaf tissues. Phosphor imager autoradiography is further investigated for use in semi-quantitative analysis of uptake of TNT by switchgrass.  相似文献   
992.
Increases in reactive nitrogen deposition are a growing concern in the U.S. Rocky Mountain west. The Rocky Mountain Airborne Nitrogen and Sulfur (RoMANS) study was designed to improve understanding of the species and pathways that contribute to nitrogen deposition in Rocky Mountain National Park (RMNP). During two 5-week field campaigns in spring and summer of 2006, the largest contributor to reactive nitrogen deposition in RMNP was found to be wet deposition of ammonium (34% spring and summer), followed by wet deposition of nitrate (24% spring, 28% summer). The third and fourth most important reactive nitrogen deposition pathways were found to be wet deposition of organic nitrogen (17%, 12%) and dry deposition of ammonia (14%, 16%), neither of which is routinely measured by air quality/deposition networks operating in the region. Total reactive nitrogen deposition during the spring campaign was determined to be 0.45 kg ha−1 and more than doubled to 0.95 kg ha−1 during the summer campaign.  相似文献   
993.
The forest hydrologic budget may be impacted by increasing CO2 and tropospheric O3. Efficient means to quantify such effects are beneficial. We hypothesized that changes in the balance of canopy interception, stem flow, and through-fall in the presence of elevated CO2 and O3 could be discerned using image analysis of leafless branches. We compared annual stem flow to the results of a computerized analysis of all branches from the 2002, 2004, and 2006 annual growth whorls of 97 ten-year-old trees from the Aspen Free-Air CO2 and O3 Enrichment (Aspen FACE) experiment in Rhinelander, WI. We found significant effects of elevated CO2 and O3 on some branch metrics, and that the branch metrics were useful for predicting stem flow from birch, but not aspen. The results of this study should contribute to development of techniques for efficient characterization of effects on the forest hydrologic budget of increasing CO2 and tropospheric O3.  相似文献   
994.
Routinef?hige, kostengünstige analytische Messverfahren sind die Grundlage für ein fl?chendeckendes Umweltmonitoring von Schadstoffen und somit für die Sicherung unserer Gesundheit und natürlichen Lebensgrundlagen. Hierbei kann die Analytik zur nachhaltigen Nutzung und zur Schonung unserer Umweltressourcen beitragen, indem auf den Einsatz umweltgef?hrdender Reagenzien verzichtet wird.  相似文献   
995.
Four plant species (oilseed rape, Brassica napus L.; red clover, Trifolium pratense L.; ryegrass, Lolium perenne L.; and tomato, Lycopersicon esculentum L.) were tested on ten soils varying widely in soil properties to assess molybdenum (Mo) toxicity. A larger range (66-fold-609-fold) of added Mo concentrations resulting in 50% inhibition of yield (ED50) was found among soils than among plant species (2-fold-38-fold), which illustrated that the soils differed widely in the expression of Mo toxicity. Toxicity thresholds based on soil solution Mo narrowed the variation among soils compared to thresholds based on added Mo concentrations. We conclude that plant bioavailability of Mo in soil depends on Mo solubility, but this alone did not decrease the variability in observed toxicity enough to be used in risk assessment and that other soil properties influencing Mo toxicity to plants need to be considered.  相似文献   
996.

Purpose

The environmental issues caused by the municipal solid waste disposal are becoming a worldwide concern.

Methods

We studied the situations both domestically and abroad by the strategic environmental assessment (SEA) approach and also conducted comprehensive evaluations of garbage disposal in Changchun City.

Results

On the basis of this study, we found that SEA is of great importance in the municipal solid waste disposal. Moreover, with the rapid socioeconomic development of Changchun City, municipal solid waste production increases on an annual basis, and thus, good waste management planning is of great significance.

Conclusions

Considering the situation of the economic development of Changchun City, garbage disposal was handled mainly in the major sanitary landfills with appropriate use of incineration technology. This plan is environmentally friendly at a relatively high degree and has met the requirements of minimum investment. It also takes into account the requirements of the development of incineration technology. Regarding environmental pollution in terms of groundwater pollution and atmospheric pollution, this plan is a feasible one by meeting various requirements with low environmental impact among the three plans discussed in this study.  相似文献   
997.

Background, aim and scope  

Perfluorinated compounds (PFCs) are global environmental pollutants that bioaccumulate in wildlife and humans. Laboratory experiments have revealed toxic effects such as delayed development, humoral suppression, and hepatotoxicity. Although numerous human blood levels have been reported, little is known about distribution in the human body. Knowledge about PFC distribution and accumulation in the human body is crucial to understanding uptake and subsequent effects as well as to conduct risk assessments. The present study reports PFC levels in human liver and breast milk from a general population living in Catalonia, Spain. Liver and milk levels are compared to previously reported levels in blood from the same geographic area as well as to other existing reports on human liver and milk levels in other countries.  相似文献   
998.

Background, aim and scope  

Weathering patinas in rocks are the result of interaction processes between rock surfaces and atmosphere, biosphere and soil. Therefore, their textural and mineral composition is strongly related to environmental and bioactivity conditions. Whereas the development of weathering patinas in atmospheric conditions is well documented (e.g. typical Mediterranean patina), only very few studies focus on their formation in a burial environment. Our study of patinas developed on the tumular structure of Reguers de Seró deals with the knowledge of burial patinas from a textural and mineralogical point of view. The aims of this study include: (1) the characterisation of the rock used in this megalithic monument as well as inferences regarding the origin of the raw material; (2) the evaluation of the patinas developed on the surface of the carved steles; and (3) the discussion of the environmental conditions (atmospheric or burial) that favoured the development of the patinas.  相似文献   
999.

Background, aim and scope  

European legislation stipulates that genetically modified organisms (GMO) have to be monitored to identify potential adverse environmental effects. A wealth of different types of monitoring data from various sources including existing environmental monitoring programmes is expected to accumulate. This requires an information system to efficiently structure, process and evaluate the monitoring data.  相似文献   
1000.
Environmental attitudes (EA), a crucial construct in environmental psychology, are a psychological tendency expressed by evaluating the natural environment with some degree of favour or disfavour. There are hundreds of EA measures available based on different conceptual and theoretical frameworks, and most researchers prefer to generate new measures rather than organize those already available. The present research provides a cumulative and theoretical approach to the measurement of EA, in which the multidimensional and hierarchical nature of EA is considered. Reported are findings from three studies on the development of a psychometrically sound, multidimensional inventory to assess EA cross-culturally, the Environmental Attitudes Inventory (EAI). The EAI has twelve specific scales that capture the main facets measured by previous research. The twelve factors were established through confirmatory factor analyses, and the EAI scales are shown to be unidimensional scales with high internal consistency, homogeneity and high test-retest reliability, and also to be largely free from social desirability.  相似文献   
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