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551.
Gray PA Duwors E Villeneuve M Boyd S Legg D 《Environmental monitoring and assessment》2003,86(1-2):129-147
In recognition of the many values that people ascribe to nature, federal, provincial, and territorial agencies worked inpartnership to complete the 'Survey on the Importance of Natureto Canadians' (SINC) in 1981, 1987, 1991, and 1996. Between 1981 and 1996, more than 80% of Canadians 15 years of age and older engaged in one or more nature-related activities. This paper describes the evolution of this cooperative monitoring program, defines a classification system as a context for the values examined by the SINC, highlights trends of some nature-related recreational activities measured by the survey, and comments onthe importance of this information to Canadians. 相似文献
552.
Roy E. Rickson Charles E. Ramsey 《Journal of the American Water Resources Association》1985,21(1):89-97
ABSTRACT: Adoption, maintenance, and operation of pollution control technology by manufacturing firms is essential to effective water resource management. In this study of 102 industries, we find that company adoption of pollution control technology and practices is primarily associated with two factors: (1) the overall company capacity for innovation in its production technology; and (2) company relationships with state and federal pollution control agencies, local government officials and professionals. Managerial attitudes about pollution and government regulation are not associated with either pollution control or commercial innovation, but are seen as basic to industry-government relationships. The data suggest an important regulatory dilemma, the problem of regulating a large number of small companies with a low capacity for innovation, but which when taken together account for large volumes of toxic effluent. 相似文献
553.
Mackechnie C Maskell L Norton L Roy D 《Journal of environmental monitoring : JEM》2011,13(10):2687-2691
Environmental monitoring is essential for assessing the current state of the environment, measuring impacts of environmental pressures and providing evidence to government. Recent UK government announcements have indicated an increased role for 'Big Society' in monitoring. In this paper, we review available literature concerning the use of citizen science for monitoring, present examples of successful volunteer monitoring work and highlight important issues surrounding the use of volunteers. We argue that in order to ensure that environmental monitoring continues to be effective it is important to learn from examples where volunteers are currently used, acknowledging constraints and identifying potential approaches which will help to maximise both their engagement and data quality. Effective partnerships between environmental monitoring organisations and volunteers may thus aid the UK in developing robust coordinated monitoring systems that will be less vulnerable to funding variances. 相似文献
554.
This paper has studied the environmental deterioration due to copper mining in Malanjkhand at Central-east India. No data
is available on environmental degradation at the studied site although geological aspects are well studied. Mine drainage
from the mines is definitively toxic. The site is also undergoing various stages of acid mine drainage (AMD) particularly
from the heap leaching sites and the tailing area. AMD impacted water steam and sediment were also analysed. Results show
substantial level of contamination of almost all segments of environment. Presence of elevated level of other heavy metal
viz. Au, Ag, Pb, Cr, Cd, Fe, Cu and base metals like Na, K in AMD impacted water and sediments is due to metal leaching effect
of AMD. Bio monitoring with the help of benthic macro invertebrates and metal accumulation in plants was also carried to know
the impact of the toxic drainage. Results prove a very significant impact on the environmental health. 相似文献
555.
Collection by honey bees of sucrose solutions treated with dimethoate continued uninterrupted until 2.9–3.9 μg/bee had been accumulated. This self-limiting dose was 20–25 times the oral LD50 for honey bees. Therefore a mean of 45 collection trips involving 1 ppm dimethoate or 11 trips involving 5 ppm was possible before foraging ceased. Losses in pollinator effectiveness and adult and larval mortality are likely to result from dimethoate contamination of nectar. 相似文献
556.
Economic effects of CO2 fertilization of crops: transforming changes in yield into changes in supply 总被引:1,自引:0,他引:1
Increasing concentrations of atmospheric carbon dioxide CO2 have a beneficial effect on crop production that would tend to offset some of the economic losses that might be generated in some areas by the climatic effects of atmospheric CO2 and other greenhouse gases. Previous estimates of the economic benefits of CO2 fertilization on world crop production, however, were based on the assumption that percent changes in supply are equal to percent changes in yield. This assumption is not valid, however, because it confounds changes in supply with changes in quantity supplied. This error leads to an overestimation of the real economic benefits of CO2 fertilization by 61–166%. The effects of CO2 fertilization on crop production, therefore, will reduce some of the potential damages caused by the climatic impacts of greenhouse gases, but by significantly less than that indicated in earlier research. 相似文献
557.
In order to investigate the role of the ionic relations in buoyancy of marine phytoplankton, voltage recordings have been made on the planktonic diatom Coscinodiscus radiatus using conventional glass microelectrode techniques. The most negative Nernst equilibrium voltage in C. radiatus is E
K, the potassium equilibrium voltage of around-85 mV. Accordingly, stable voltages of-40 to-80 mV were recorded from C. radiatus which conforms to the general theory of electro-diffusion of ions through membranes (voltage range V
d). In addition, membrane voltages much more negative, e.g. up to-140 mV (voltage range V
p), have been recorded in C. radiatus; these voltages demonstrate the operation of an electrogenic pump. Within the voltage range V
d, light-on and-off (microscope illumination) caused weak hyper- and depolarizations by about 2 mV with a time constant of about 10 s. Also within V
d, spontaneous oscillations could be observed with a frequency of about 0.03 Hz and irregular amplitudes up to 30 mV. These phenomena are simulated by a model for electrocoupling of the major ion transporters in plants, as worked out for guard cells with their subtle osmoregulatory system. Equivalent mechanisms are suggested to operate in planktonic diatoms for adjustment of buoyancy by appropriate uptake and release of ions. 相似文献
558.
The ecological integrity of the Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle and A. Young) alliance is being severely interrupted by post-fire invasion of non-native annual grasses. To curtail this invasion, successful post-fire revegetation of perennial grasses is required. Environmental factors impacting post-fire restoration success vary across space within the Wyoming big sagebrush alliance; however, most restorative management practices are applied uniformly. Our objectives were to define probability of revegetation success over space using relevant soil-related environmental factors, use this information to model cost of successful revegetation and compare the importance of vegetation competition and soil factors to revegetation success. We studied a burned Wyoming big sagebrush landscape in southeast Oregon that was reseeded with perennial grasses. We collected soil and vegetation data at plots spaced at 30?m intervals along a 1.5?km transect in the first two years post-burn. Plots were classified as successful (>5?seedlings/m(2)) or unsuccessful based on density of seeded species. Using logistic regression we found that abundance of competing vegetation correctly predicted revegetation success on 51?% of plots, and soil-related variables correctly predicted revegetation performance on 82.4?% of plots. Revegetation estimates varied from $167.06 to $43,033.94/ha across the 1.5?km transect based on probability of success, but were more homogenous at larger scales. Our experimental protocol provides managers with a technique to identify important environmental drivers of restoration success and this process will be of value for spatially allocating logistical and capital expenditures in a variable restoration environment. 相似文献
559.
Kamaraj Jesuraja Sekar Selvam Roy Priyadarsi D. Senapathi Venkatramanan Chung Sang Yong Perumal Muthukumar Nath Akhila V. 《Environmental science and pollution research international》2021,28(23):29056-29074
Environmental Science and Pollution Research - We assessed groundwater pollution index (GPI) and groundwater quality of coastal aquifers from Tiruchendur in South India for drinking and irrigation... 相似文献