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301.
Environmental Management - In the United States, forest governance practices have utilized a variety of public participation mechanisms to improve decision-making and instill public legitimacy.... 相似文献
302.
De Vargas Jocelina Paranhos Rosa Bastos Marília Camotti Al Badany Maha Gonzalez Rolando Wolff Delmira Santos Danilo Rheinheimer Dos Labanowski Jérôme 《Environmental science and pollution research international》2021,28(24):30955-30974
Environmental Science and Pollution Research - The fate of pharmaceuticals during the treatment of effluents is of major concern since they are not completely degraded and because of their... 相似文献
303.
Mary F. Willson Toni L. De Santo Carlos Sabag Juan J. Armesto 《Conservation biology》1994,8(2):508-520
The diversity and relative abundance of south-temperate rainforest birds decreased as the size of the habitat patch decreased. Ecological categories, including endemics, mutualists (pollinators, seed dispersers), understory species, and species dependent on large trees, were not differentially sensitive to patch size. Nevertheless, most of the species with at least marginally significant declines were endemic (6 of 7 species), covered nesters (6 of 7 species), and understory dwellers (5 of 7 species). Some mutualists and big-tree users were also affected. The losses will become more severe as clearing of the forest continues. Possible mitigation measures include leaving small stands of forest and corridors between habitat patches and, in certain circumstances, alternative agricultural practices. 相似文献
304.
Two kinds of regional disparities can be distinguished in Belgium. First there is the internationally well‐known dispute between Flanders and Wallonia. Secondly, there are large disparities within the regions. Three policy levels deal with these disparities: the (Flemish) regional level, the national government level and the EEC level. The purpose of this paper is to sketch the regional problems in Belgium, to analyse the policies that deal with them, to consider the co‐ordination problems between them and to shed some light on the public choice aspects of government interventions. It is concluded that regional policy in Belgium is a highly politicised affair. Furthermore public attention paid to regional policies has outgrown the importance of our regional disparities. Even other forms of micro‐economic policy are jeopardised by regional disparities and the resulting pressure. 相似文献
305.
A. Deluca Luca R. Wagener C. Bough L. H. Melges De Figueiredo R. Carreira K. Wagener 《Chemistry and Ecology》1992,6(1):19-39
A survey was made in an area of 28 km2 around the outlest of Ipanema's submarine outfall in order to evaluate the impact of the raw domestic sewage effluent on coastal waters. Nutrient concentrations, dissolved oxygen, particulate matter and other physico-chemical parameters were measured monthly for 15 months. Copper and lead concentrations were also determined for two of the samplings.
The outfall has been in operation for 18 years, and the parameters measured within the observation area appear to be in steady state. From the observed radial concentration gradients within the survey area, a real extension of the steady state distribution of particulate matter and of sewage-derived nitrogen was estimated. the stationary cloud of particulate organic matter was about 150 km2. From its total inventory and the discharge rate, a mean residence time of the particles in the sea of 56 days is estimated, prior to their being decomposed by bacterial action or settling to the bottom. for sewage derived N (as ammonia or nitrate), the steady state amount (above background) covers an area of about 60 km2 and leads to a mean residence time of 5 ± 1 days in the ocean. Phosphorus is readily absorbed by the phytoplankton.
The presence of temperature gradients established by cold upwelling waters controls the dispersion of the sewage material and the rising of the sewage plume to the surface waters. 相似文献
The outfall has been in operation for 18 years, and the parameters measured within the observation area appear to be in steady state. From the observed radial concentration gradients within the survey area, a real extension of the steady state distribution of particulate matter and of sewage-derived nitrogen was estimated. the stationary cloud of particulate organic matter was about 150 km2. From its total inventory and the discharge rate, a mean residence time of the particles in the sea of 56 days is estimated, prior to their being decomposed by bacterial action or settling to the bottom. for sewage derived N (as ammonia or nitrate), the steady state amount (above background) covers an area of about 60 km2 and leads to a mean residence time of 5 ± 1 days in the ocean. Phosphorus is readily absorbed by the phytoplankton.
The presence of temperature gradients established by cold upwelling waters controls the dispersion of the sewage material and the rising of the sewage plume to the surface waters. 相似文献
306.
Michiel F. De Vires 《Conservation biology》1995,9(1):25-33
Nature conservation in densely populated areas, as in western Europe, faces the continuous loss and fragmentation of suitable habitats for wild species. Current conservation measures have not been successful in countering this threat to biological diversity, so a new concept for nature conservation is required. I propose using the habitat requirements of large herbivores as a key to the design of large-scale nature reserves. Large herbivores can have a significant influence on vegetation composition and thus act as keystone species. Moreover, they require large tracts of land and can be considered an umbrella species group for the preservation of other plants and animals. I review the present status of nature reserves in the European Union concerning size distribution and the occurrence of large herbivores and their predators. I argue that habitat fragmentation and the increased management costs of maintaining seminatural areas necessitate an enlargement of existing reserves, a process-oriented management approach, and a minimization of human influence for the long-term preservation of biological diversity. 相似文献
307.
This paper presents a test scheme for assessing the biodegradation potential of polymers, starting with aquatic screening systems (aerobic and anaerobic) and continuing to long-term systems. At the end of the scheme the material has to prove its behavior under the relevant disposal conditions. Aerobic screening was performed mainly under aquatic conditions, but also in soil, using BOD-respirometry. Carbon balances were performed to obtain a better evaluation of the biodegradation potential. Under anaerobic conditions, biodegradation in an aquatic medium was followed by measuring CH4 and CO2 production. Polymers not fully degraded in the screening systems were tested in aquarium systems for at least 1 year. Biodegradation was followed by monitoring the DOC released in the water, mass loss, and microbial growth on the samples and in the water as well as via FTIR spectroscopy and SEM pictures. Results are presented for the polymers PHB, PHBV, PCL, Mater-Bi AI05H and ZF03U, and Bioceta. By combining the data from the screening with the aquarium system, a good picture of the degradation behavior of the polymers is obtained.Paper presented at the Bio/Environmentally Degradable Polymer Society—Third National Meeting, June 6–8, 1994, Boston, Massachusetts. 相似文献
308.
309.
B.?H.?J.?De?JongEmail author A.?Hellier M.?A.?Castillo-Santiago R.?Tipper 《Mitigation and Adaptation Strategies for Global Change》2005,10(2):265-278
We present a methodology for testing and applying a regional baseline for carbon (C) emissions from land-use change, using a spatial modelling approach (hereafter called the Climafor approach). The methodology is based on an analysis of causal factors of previous land-use change (Castillo et al. 2005). Carbon risk matrices constructed from the spatial correlation analysis between observed deforestation and driving factors (Castillo et al. 2005), are used to estimate future carbonemissions within acceptable limits for a forest conservation project. The performance of two risk matrices were tested by estimating carbon emissions between 1975 and 1996 from randomly selected sample plots of sizes varying from 1,600 to 10,000 ha and comparing the results of the observed emissions from these sample plots with the model estimations. Expected emissions from continued land-use change was estimated for the community applying the risk matrices to the current land cover. The methodology provides an objective means of constructing baseline scenarios including confidence intervals, using the sum of variances of the various data sources, such as measured carbon densities, classification errors, errors in the risk matrices, and differences between the model prediction and observed emissions of sample plots due to sample size. The procedures applied in this study also give an indication of the impact of the variance in the various data sources on the size of the confidence intervals, which allows project developers to decide what data sources are essential to improve his baseline. The modelling approach to estimate the deforestation pattern is based on readily available cartographic and census data, whereas data on carbon densities are required to assess the potential for forest conservation projects to offset carbon emissions. 相似文献
310.