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651.
Deming's well known Plan‐Do‐Check‐Act cycle offers a systematic method for solving environmental problems. But the process is an iterative one: You may need to repeat some steps of the cycle several times before you achieve the desired goal. © 2000 John Wiley & Sons, Inc. 相似文献
652.
Globally soil quality and food security continue to decrease indicating that agriculture and the food system need to adapt. Improving connection to the soil by knowledge exchange can help achieve this. We propose a framework of three types of connections that allow the targeting of appropriate messages to different groups of people. Direct connection by, for example, handling soil develops soil awareness for management that can be fostered by farmers joining groups on soil-focused farming such as organic farming or no-till. Indirect connections between soil, food and ecosystem services can inform food choices and environmental awareness in the public and can be promoted by, for example, gardening, education and art. Temporal connection revealed from past usage of soil helps to bring awareness to policy workers of the need for the long-term preservation of soil quality for environmental conservation. The understanding of indirect and temporal connections can be helped by comparing them with the operations of the networks of soil organisms and porosity that sustain soil fertility and soil functions. 相似文献
653.
Anne D. Bjorkman Mariana Garca Criado Isla H. Myers-Smith Virve Ravolainen Ingibjrg Svala Jnsdttir Kristine Bakke Westergaard James P. Lawler Mora Aronsson Bruce Bennett Hans Gardfjell Starri Heimarsson Laerke Stewart Signe Normand 《Ambio》2020,49(3):678-692
Changes in Arctic vegetation can have important implications for trophic interactions and ecosystem functioning leading to climate feedbacks. Plot-based vegetation surveys provide detailed insight into vegetation changes at sites around the Arctic and improve our ability to predict the impacts of environmental change on tundra ecosystems. Here, we review studies of changes in plant community composition and phenology from both long-term monitoring and warming experiments in Arctic environments. We find that Arctic plant communities and species are generally sensitive to warming, but trends over a period of time are heterogeneous and complex and do not always mirror expectations based on responses to experimental manipulations. Our findings highlight the need for more geographically widespread, integrated, and comprehensive monitoring efforts that can better resolve the interacting effects of warming and other local and regional ecological factors. 相似文献
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656.
Inverse geochemical modeling from PHREEQC, and multivariate statistical methods were jointly used to define the genetic origin of chemical parameters of groundwater from the Voltaian aquifers in the Afram Plains area. The study finds, from hierarchical cluster analysis that there are two main hydrochemical facies namely the calcium-sodium-chloride-bicarbonate waters and the magnesium-potassium-sulfate-nitrate waters in the northern and southern sections, respectively, of the Afram Plains area. This facies differentiation is confirmed by the distribution of the SO(4)(2-)/Cl(-) ratio, which associates groundwater from the northern and southern sections to areas influenced by contact with evaporites and seawater, respectively. Principal component analysis (PCA) with varimax rotation using the Kaiser criterion identifies four principal sources of variation in the hydrochemistry. Mineral saturation indices calculated from both major ions and trace elements, indicate saturation-supersaturation with respect to calcite, aragonite, k-mica, chlorite, rhodochrosite, kaolinite, sepiolite, and talc, and undersaturation with respect to albite, anorthite, and gypsum in the area. Inverse geochemical modeling along groundwater flowpaths indicates the dissolution of albite, anorthite and gypsum and the precipitation of kaolinite, k-mica, talc, and quartz. Both the PCA and inverse geochemical modeling identify the incongruent weathering of feldspars as the principal factors controlling the hydrochemistry in the Afram Plains area. General phase transfer equations have been developed to characterize the geochemical evolution of groundwater in the area. A very good relationship has been established between calcite and aragonite saturation indices in the Afram Plains area, with R(2)=1.00. 相似文献
657.
We consider the extent to which the Mackenzie Valley Resource Management Act (MVRMA) provides an opportunity for deliberative democracy to emerge within the context of resource management in Canada's North. The focus is on the extent to which the tenets of deliberative democracy are exercised in the environmental assessment (EA) of the Snap Lake diamonds project. Data collection included semi-structured interviews with assessment participants, and a review of documentation surrounding the EA process, and the case study. Results combined four principles of deliberative democracy: generality, autonomy, power neutrality, and ideal role taking. The EA conducted under the MVRMA can serve as a deliberative process, as illustrated by opportunities for dialogue, access to different perspectives, and learning outcomes. However, many of these positive results occurred through nonmandated technical sessions. The absence of participant funding also limits the deliberative potential of the MVRMA. 相似文献
658.
Human activities have impacted the environment since the first toolmakers learned to make fire. As the human population has grown and changed, so has our impact on the environment. Currently the world's population is estimated at 6–7 billion, and that number of people, along with the billions of domesticated animals, and their activities, are large enough to have major global and regional impacts. Climate change, declining fish populations in the oceans, and ever decreasing ranges for “wild” ecosystems are the most obvious impacts. Other impacts may be surprising to many people, especially those impacts that are regional and not raised to the level of international concern.This paper will take a very high level look at a number of global, regional and local human interactions with the environment, and how mitigating those impacts requires a very broad and multi-disciplinary response. Examples will focus on water, carbon and energy, all of which are needed for life, as we know it, to exist. Stewardship will be shown to involve determination and monitoring of many key indicators and environmental processes, followed by the tough decisions on how to steward those processes to maintain a healthy environment for all the planet's inhabitants. Stewardship is not easy, and there are few cases where solutions can be neatly divided into good or bad, positive or negative. 相似文献
659.
This research tested whether limnological conditions, biological characteristics of fish and anthropogenic impacts influenced the assimilation of methylmercury into the muscle of a sedentary piscivorous fish, Cichla spp., from three rivers (Negro, Madeira, Tapajós) and two hydroelectric reservoirs (Balbina, Tucuruí) within the Brazilian Amazon. Methylmercury in this fish ranged from 0.04 to 1.43microgg(-1) w.w. across sites. No significant differences were observed in the methylmercury concentrations between males and females, or for different morphotypes of this species. Positive correlations were found between methylmercury and fish body weight. No differences were found between the weight normalized methylmercury (MeHg) concentrations or its percent of total mercury in fish from the three rivers; weight normalized MeHg was highest in one of the two reservoirs. In Rio Tapajós, where gold mining and deforestation cause high water turbidity, fish showed the highest MeHg and concentrations were different across the four sites examined. In all sampling areas, the %MeHg was found to be higher than 70. 相似文献
660.
Quintin L. Williams Jr. Author Vitae Bruce H. Alexander Author Vitae Author Vitae Timothy R. Church 《Journal of Safety Research》2010,41(1):31-37