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101.
In this paper, we assess the status of the air quality in the Lake Baikal region which is strongly influenced by the presence of anthropogenic pollution sources. We combined the local data, with global databases, remote sensing imagery and modelling tools. This approach allows to inventorise the air-polluting sources and to quantify the air-quality concentration levels in the Lake Baikal region to a reasonable level, despite the fact that local data are scarcely available. In the simulations, we focus on the month of July 2003, as for this period, validation data are available for a number of ground-based measurement stations within the Lake Baikal region.  相似文献   
102.
Iron electrodes were used for electrocoagulation (EC) treatment of wastewater from a dairy plant. Electrolysis time, pH, current density and distance between electrodes were considered to assess the removal efficiency of chemical oxygen demand (COD), total solids (TS) and their fractions and turbidity. Samples were collected from the effluent of a dairy plant using a sampling methodology proportional to the flow. The treatments were applied according to design factorial of half fraction with two levels of treatments and three repetitions at the central point. The optimization of parameters for treating dairy industry effluent by electrocoagulation using iron electrodes showed that electric current application for 15 minutes, an initial sample pH close to neutral (pH 7.0) and a current density of 50 A . m?2 resulted in a significant reduction in COD by 58 %; removal of turbidity, suspended solids and volatile suspended solids by 95 %; and a final treated effluent pH of approximately 9.5. Negative consequences of the type of electrode used were the emergence of an undesirable color and an increase in the proportion of dissolved solids in the treated effluent.  相似文献   
103.
Iron electrodes were used for electrocoagulation (EC) treatment of wastewater from a dairy plant. Electrolysis time, pH, current density and distance between electrodes were considered to assess the removal efficiency of chemical oxygen demand (COD), total solids (TS) and their fractions and turbidity. Samples were collected from the effluent of a dairy plant using a sampling methodology proportional to the flow. The treatments were applied according to design factorial of half fraction with two levels of treatments and three repetitions at the central point. The optimization of parameters for treating dairy industry effluent by electrocoagulation using iron electrodes showed that electric current application for 15 minutes, an initial sample pH close to neutral (pH 7.0) and a current density of 50 A (.)(m-2) resulted in a significant reduction in COD by 58 %; removal of turbidity, suspended solids and volatile suspended solids by 95 %; and a final treated effluent pH of approximately 9.5. Negative consequences of the type of electrode used were the emergence of an undesirable color and an increase in the proportion of dissolved solids in the treated effluent.  相似文献   
104.
The interdisciplinary concept of landscape multifunctionality provides a suitable platform to combine or disentangle effects of multiple environmental stressors acting on the landscape. The concept allows mapping of trade-offs, synergies, and priority conflicts between individual landscape functions, thus providing easily accessible, hands-on means to communicate findings of environmental research to decision makers and society. This rapid communication provides an overview of current developments and potential future research avenues in landscape multifunctionality.  相似文献   
105.
With the increasing concern about the serious global energy crisis and high energy consumption during high content solid wastes (HCSWs) treatment, microbial fuel cell (MFC) has been recognized as a promising resource utilization approach for HCSW stabilization with simultaneous electrical energy recovery. In contrast to the conventional HCSW stabilization processes, MFC has its unique advantages such as direct bio-energy conversion in a single step and mild reaction conditions (viz., ambient temperature, normal pressure, and neutral pH). This review mainly introduces some important aspects of electricity generation from HCSWand its stabilization in MFC, focusing on: (1) MFCs with different fundamentals and configurations designed and constructed to produce electricity from HCSW; (2) performance of wastes degradation and electricity generation; (3) prospect and deficiency posed by MFCs with HCSWas substrates. To date, the major drawback of MFCs fueled by HCSW is the lower power output than those using simple substrates. HCSW hydrolysis and decomposition would be a major tool to improve the performance of MFCs. The optimization of parameters is needed to push the progress of MFCs with HCSW as fuel.
  相似文献   
106.
Feral swine are estimated to annually cost hundreds of millions of dollars in economic loss to property and agriculture in the USA, while their ecological consequences remain largely unmeasured. Using submeter-accurate Global Positioning System technology over a multiyear project, we are quantifying in a novel way the spatial and temporal attributes of swine rooting damage within 587 ha of ecologically sensitive wetland plant communities at Avon Park Air Force Range in south-central Florida. We delineated damage polygons from 0.0023 to 4,335 m2 and were able to document recurrent damage through time at most sites during each assessment. For each polygon, we also estimated the age of damage and assigned to it a severity index, qualities of the rooting in which we detected changes in proportions over time. Spatially explicit damage assessments at fine scales conducted over several years can assist land managers in determining effects of rooting on rare plant populations, and will allow investigators to hypothesize what factors are driving patterns of this disturbance across ecologically sensitive plant communities.  相似文献   
107.
108.
To be effective, climate change adaptation needs to be mainstreamed across multiple sectors and greater policy coherence is essential. Using the cases of Malawi, Tanzania and Zambia, this paper investigates the extent of coherence in national policies across the water and agriculture sectors and to climate change adaptation goals outlined in national development plans. A two-pronged qualitative approach is applied using Qualitative Document Analysis of relevant policies and plans, combined with expert interviews from non-government actors in each country. Findings show that sector policies have differing degrees of coherence on climate change adaptation, currently being strongest in Zambia and weakest in Tanzania. We also identify that sectoral policies remain more coherent in addressing immediate-term disaster management issues of floods and droughts rather than longer-term strategies for climate adaptation. Coherence between sector and climate policies and strategies is strongest when the latter has been more recently developed. However to date, this has largely been achieved by repackaging of existing sectoral policy statements into climate policies drafted by external consultants to meet international reporting needs and not by the establishment of new connections between national sectoral planning processes. For more effective mainstreaming of climate change adaptation, governments need to actively embrace longer-term cross-sectoral planning through cross-Ministerial structures, such as initiated through Zambia’s Interim Climate Change Secretariat, to foster greater policy coherence and integrated adaptation planning.  相似文献   
109.
Today, a variety of different approaches to the recovery of phosphorus from wastewater, sludge, and sludge ash exist. These approaches differ basically by the origin of the used matter (wastewater, sludge liquor, fermented or nonfermented sludge ash) and the process (precipitation, wet-chemical extraction, and thermal treatment). To rate them according to their characteristics, the latter were phrased as hypotheses and subjected to an international expert survey. The survey showed that phosphorus recovery is expected to become an established process over the next 20 years in industrialized countries for economic reasons. A decisive aspect in this regard will be the quality of the produced fertilizer. Simple technologies such as the recovery from sludge liquor seem to be preferred. If sludge is incinerated, phosphorus recycling from ash then becomes more interesting and has to be considered. Phosphorus recovery and source-separating sanitation technologies are more appropriate for industrialized countries than for developing countries. Because the growing awareness of environmental issues will prevent sludge from being used agriculturally in an increasing number of countries in the next decade, the market potential for nutrient recovery technologies will increase in the immediate future.  相似文献   
110.
We examine the advantages and disadvantages of a methodological framework designed to analyze the poorly understood relationships between the ecosystem properties of large portions of land, and their capacities (stocks) to provide goods and services (flows). These capacities (stocks) are referred to as landscape functions. The core of our assessment is a set of expert- and literature-driven binary links, expressing whether specific land uses or other environmental properties have a supportive or neutral role for given landscape functions. The binary links were applied to the environmental properties of 581 administrative units of Europe with widely differing environmental conditions and this resulted in a spatially explicit landscape function assessment. To check under what circumstances the binary links are able to replace complex interrelations, we compared the landscape function maps with independently generated continent-wide assessments (maps of ecosystem services or environmental parameters/indicators). This rigorous testing revealed that for 9 out of 15 functions the straightforward binary links work satisfactorily and generate plausible geographical patterns. This conclusion holds primarily for production functions. The sensitivity of the nine landscape functions to changes in land use was assessed with four land use scenarios (IPCC SRES). It was found that most European regions maintain their capacity to provide the selected services under any of the four scenarios, although in some cases at other locations within the region. At the proposed continental scale, the selected input parameters are thus valid proxies which can be used to assess the mid-term potential of landscapes to provide goods and services.  相似文献   
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