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11.
Critical to habitat management is the understanding of not only the location of animal food resources, but also the timing of their availability. Grizzly bear (Ursus arctos) diets, for example, shift seasonally as different vegetation species enter key phenological phases. In this paper, we describe the use of a network of seven ground-based digital camera systems to monitor understorey and overstorey vegetation within species-specific regions of interest. Established across an elevation gradient in western Alberta, Canada, the cameras collected true-colour (RGB) images daily from 13 April 2009 to 27 October 2009. Fourth-order polynomials were fit to an RGB-derived index, which was then compared to field-based observations of phenological phases. Using linear regression to statistically relate the camera and field data, results indicated that 61% (r (2)?= 0.61, df = 1, F?= 14.3, p?= 0.0043) of the variance observed in the field phenological phase data is captured by the cameras for the start of the growing season and 72% (r (2)?= 0.72, df = 1, F?= 23.09, p?= 0.0009) of the variance in length of growing season. Based on the linear regression models, the mean absolute differences in residuals between predicted and observed start of growing season and length of growing season were 4 and 6?days, respectively. This work extends upon previous research by demonstrating that specific understorey and overstorey species can be targeted for phenological monitoring in a forested environment, using readily available digital camera technology and RGB-based vegetation indices.  相似文献   
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Journal of Polymers and the Environment - Adsorptive removal of toxic metals from water using materials with high removal capability and sufficient environmental degradability is of great...  相似文献   
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Environmental Science and Pollution Research - Phosphorus is one of the main nutrients required for all life. Phosphorus as phosphate form plays an important role in different cellular processes....  相似文献   
14.
Climate change phenomenon can be seen as a simple but daunting problem. The lack of equity in emission reduction burden sharing regime, will cause a need for a greater sacrifice for poor or less developed countries. Thus, the evaluation of different aspects of equity at a national scale and presenting a top–down model of equity for allocation of GHGs emission (such as GERA) in line with sustainable development is the main objective of this study. In this study, the five equity principles proposed in the literature namely (1) population distribution, (2) GHGs emissions, (3) GDP, (4) trend of economic growth and (5) per capita of carbon productivity as appropriate criteria of equity estimation. Due to the different decision makers' preferences, different weights are allocated to indicators and analyzed. Iran has been considered as a case study, and these criteria were applied at national level to propose an allowance allocation scheme. The result of applying GERA for Iran, at provincial level and under the five equity criteria, determines which provinces have to shoulder higher reduction burdens, and makes a room for less developed provinces for growth. Based on these results, this model demonstrated to be more sensitive to criteria selection rather than to the weight factors. In addition, shifting to low carbon technologies or renewables, careful evaluation of current emission–income pattern, improving of energy intensity and finally, adjustment of secondary industries (manufacturing) based on ecological and natural resources of each region are suggested as the most efficient approaches toward sustainability and green development for the case study.  相似文献   
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Conservation success is contingent on assessing social and environmental factors so that cost‐effective implementation of strategies and actions can be placed in a broad social–ecological context. Until now, the focus has been on how to include spatially explicit social data in conservation planning, whereas the value of different kinds of social data has received limited attention. In a regional systematic conservation planning case study in Australia, we examined the spatial concurrence of a range of spatially explicit social values and land‐use preferences collected using a public participation geographic information system and biological data. We used Zonation to integrate the social data with the biological data in a series of spatial‐prioritization scenarios to determine the effect of the different types of social data on spatial prioritization compared with biological data alone. The type of social data (i.e., conservation opportunities or constraints) significantly affected spatial prioritization outcomes. The integration of social values and land‐use preferences under different scenarios was highly variable and generated spatial prioritizations 1.2–51% different from those based on biological data alone. The inclusion of conservation‐compatible values and preferences added relatively few new areas to conservation priorities, whereas including noncompatible economic values and development preferences as costs significantly changed conservation priority areas (48.2% and 47.4%, respectively). Based on our results, a multifaceted conservation prioritization approach that combines spatially explicit social data with biological data can help conservation planners identify the type of social data to collect for more effective and feasible conservation actions.  相似文献   
17.
Heavy metal contamination of soil resulting from anthropogenic sources poses a significant challenge in many industrialized societies. The current technologies employed for removal of heavy metals often involve expensive ex-situ processes requiring sophisticated equipment and removal, transportation, and purification of the soil. Generally, in-situ remedial technologies are favored to ex-situ methods for detoxification, neutralization, degradation, or immobilization of contaminants. In-situ bioremediation is increasingly favored because of its effectiveness and low cost. A new type of bioremediation, known as vegetative remediation or “phytoremediation,” uses metal-tolerant hyperaccumulator plants to take up metal ions from soils and store them in their aboveground parts. To select the appropriate phytoremediation technology, one must understand the technical feasibility, cost effectiveness, and availability of the suitable plant species. Equally important is determining whether the site's soil conditions are optimal to enhance or restore the soil biological activity. Before phytoremediation can be exploited on a contaminated site, greenhouse-scale confirmatory testing is necessary to measure plant uptake and correlate shoot metal concentrations to available soil metals. These tests also validate that the harvesting and subsequent disposal of metal-containing plant tissues are environmentally safe and manageable.  相似文献   
18.
Groundwater is a basic source of drinking water supply for urban and rural areas. This is especially the case for communities located in arid and semi-arid regions that rely on groundwater for drinking purposes. The present study set out to assess the potential health impacts of water impurities and to investigate the qualitative status of drinking water in Robat Karim rural areas, located in southwest Tehran, Iran. A total of 66 samples were collected from the water distribution network of 11 villages (33 sampling points, on two occasions) during September 2020 and were tested in terms of the most common quality parameters such as pH, mercury (Hg), lead (Pb), copper (Cu), zinc (Zn), chloride (Cl), chlorate (ClO3), nitrite (NO2), nitrate (NO3), and flouride (F). Multiple methods and indexes including water quality index (WQI), hazard quotient (HQ), and hazard index (HI), were worked out to assess the quality of water and health risk assessment of NO3 Pb2+ and Hg2+. The results revealed that 33% and 90% of sampling sites have significantly high nitrate and total hardness (TH) concentrations, exceeding the maximum permissible limits set by World Health Organization (WHO; 50 and 200 mg/L, respectively). Furthermore, five sampling points exhibited poor WQIs mainly related to NO3 and TH. HQ values higher than 1 for nitrate were noticed in most sampling locations. Except for one sampling point, the HQ obtained for Pb2+ and Hg2+ were below 1 indicating no obvious health hazard. This study represents that children and infants are at higher risk of chronic toxicity by excess NO3 intake. The health hazard that is yet imposed on the community by NO3 necessitates regular monitoring of drinking water, the use of advanced technologies to purify water or otherwise alternative resources should be proposed.  相似文献   
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20.
This study examined the biodegradation of phenol by Ralstonia eutropha in a Kissiris-immobilized cell bioreactor (ICB), operated in a repeated batch recycling mode. The steady biodegradation rate of 23.7 mg/g/h, over a wide range of the initial phenol concentrations up to 1400 mg/L in the ICB, indicated an increased tolerance limit of the Kissiris-immobilized cells towards phenol. Both Haldane and Luong substrate inhibition models were used to describe biodegradation kinetic of free cells system. The Haldane equation gave the following values for the biokinetic parameters: micro(max) = 0.36 h(-1), Ks = 40.48 mg/L, and Ki = 181.9 mg/L. However, according to the Luong model, these parameters were micromax) = 0.23 h(-1), Ks = 24.8 mg/L, Sm = 1018 mg/L, and n = 1.3. By following appropriate operational conditions and use of the ICB, it was found to be possible to extend the efficiency of the highly porous structure of the siliceous mineral Kissiris in cell immobilization. This holds significant promise for pollutant biodegradation issues.  相似文献   
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