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441.
Watershed land use in suburban areas can affect stream biota through degradation of instream habitat, water quality, and riparian vegetation. By monitoring stream biotic communities in various geographic regions, we can better understand and conserve our watershed ecosystems. The objective of this study was to examine the relationship between watershed land use and the integrity of benthic invertebrate communities in eight streams that were assessed over a 3-year period (2001-2003). Sites were selected from coastal Rhode Island watersheds along a residential land-use gradient (4-59%). Using the rapid bioassessment protocol, we collected biological, physicochemical, habitat, and nutrient data from wadeable stream reaches and compared metrics of structure and integrity. Principal component analyses showed significant negative correlation of indicators for stream physicochemical, habitat, and instream biodiversity with increasing residential land use (RLU) in the watershed. The physicochemical variables that were most responsive to percent RLU were conductivity, instream habitat, nitrate, and dissolved inorganic nitrogen (DIN). The positive correlation of DIN with percent RLU indicated an anthropogenic source of pollution affecting the streams. The biotic composition of the streams shifted from sensitive to insensitive taxa as percent RLU increased; the most responsive biological variables were percent Ephemeroptera, percent Scrapers, percent Insects, and the Hilsenhoff biotic index. These data show the importance of land management and conservation at the watershed scale to sustaining the biotic integrity of coastal stream ecosystems.  相似文献   
442.
Policies on economic use of natural resources require considerations to social and cultural values. In order to make those concrete in a planning context, this paper aims to interpret social and cultural criteria, identify indicators, match these with verifier variables and visualize them on maps. Indicators were selected from a review of scholarly work and natural resource policies, and then matched with verifier variables available for Sweden’s 290 municipalities. Maps of the spatial distribution of four social and four cultural verifier variables were then produced. Consideration of social and cultural values in the studied natural resource use sectors was limited. The spatial distribution of the verifier variables exhibited a general divide between northwest and south Sweden, and regional rural and urban areas. We conclude that it is possible to identify indicators and match them with verifier variables to support inclusion of social and cultural values in planning.  相似文献   
443.
Organic agriculture, with its restrictions on the use of synthetic chemical inputs, seems to offer a low-residue alternative to conventional methods. In Europe, the Council Regulation n. 2092/91/EEC regulates the production and trade of organic products and foodstuffs; national and regional legislation in Italy gives specific guidance on the surveillance of organic agriculture. However, monitoring of specific chemical residues in organic foodstuffs is part of the regular controls on food, aiming to safeguard consumer's health. Monitoring programs are coordinated at the national level by the Ministry of Health and at local level by Regional authorities. In Lombardy, in accordance with the provisions of the General Directorate of Health of the Region and under the supervision of the 15 Local Health Units, a monitoring program of pesticide residues in food of plant origin is undertaken every year. The International Centre for Pesticides and Health Risk Prevention (ICPS), on behalf of the General Directorate of Health of the Region of Lombardy, has been collecting and elaborating the data resulting from the analysis of food samples, carried out by the local laboratories. During the period 2002–2005, a total of 3508 samples food of plant origin were analyzed for pesticide residues, among which were 266 samples of organic farming products. Commodities were classified into groups (citrus fruits, legumes, vegetables, potatoes, processed products, cereals, and fruit other than citrus) and the outcomes of the analyses were reported by year, origin of the sample and presence/absence of pesticide residues. Results showed that the vast majority of organic farming products were in conformity with the relevant legislation and did not contain detectable pesticide residues. A limited amount of samples had residues at concentration below the Maximum Residue Limit (MRL). Only in one sample the residue level was above the MRL, however it did not pose a concern for public health, as demonstrated by the outcomes of dietary risk assessment. Organic fruits and vegetables can be expected to contain fewer agrochemical residues than conventionally grown alternatives. There is a widespread belief that organic agriculture products are safer and healthier than conventional foods. It is difficult to come to conclusions, but what should be made clear to the consumer is that “organic” does not automatically equal “safe”. In the absence of adequate comparative data, additional studies in this area of research are required.  相似文献   
444.
Biochar addition to soil is currently being investigated as a novel technology to remediate polluted sites. A critical consideration is the impact of biochar on the intrinsic microbial pollutant degradation, in particular at sites polluted with a mixture of readily biodegradable and more persistent organic pollutants. We therefore studied the impact of biochar (2% on dry weight basis) on the fate of volatile petroleum hydrocarbons in an aerobic sandy soil with batch and column studies. The soil-water partitioning coefficient, K(d), was enhanced in the biochar-amended soil up to a factor 36, and petroleum hydrocarbon vapor migration was retarded accordingly. Despite increased sorption, in particular of monoaromatic hydrocarbons, the overall microbial respiration was comparable in the biochar-amended and unamended soil. This was due to more rapid biodegradation of linear, cyclic and branched alkanes in the biochar amended soil. We concluded that the total petroleum hydrocarbon degradation rate was controlled by a factor other than substrate availability and the reduced availability of monoaromatic hydrocarbons in the biochar amended soil led to greater biodegradation of the other petroleum compounds.  相似文献   
445.
446.
To facilitate the choice of more sustainable animal-based products in the diet, a Swedish meat guide providing complex, multi-layered environmental information to non-experts has been developed. This study evaluated reception of this guide by consumers. In five focus groups, participants (“interested consumers”) carried out a joint environmental and animal welfare ranking assignment to test understanding and use of the guide. The type and detail of indicators (e.g. carbon footprint) in the meat guide suited the audience. The guide stimulated discussion on ethical issues and quality aspects of meat, revealed perceived obstacles to reducing meat consumption and provided an understanding that any food product chosen comes with trade-offs.  相似文献   
447.

Objective

To evaluate fetal brain development using MRI (magnetic resonance imaging) in CDH (congenital diaphragmatic hernia).

Methods

52 isolated left CDH and 104 control fetuses were imaged using MRI. Brain morphometry (Biparietal diameter—BPD, brain fronto-occipital diameter—BFOD, third ventricle, posterior ventricles, transcerebellar diameter—TCD, anteroposterior and craniocaudal cerebellar vermis diameter—AP and CC) and cortical structures (bilateral cingulate fissure—CF, insular fissure—IF, insular depth - ID) were compared with controls using Mann–Whitney test.

Results

Median gestational age at MRI (p = 0.95)and the median biparietal diameter (p = 0.737) were comparable. Among morphometric parameters, only the brain fronto-occipital diameter was significantly smaller in CDH (p = 0.001) and the third ventricle was significantly greater in CDH (<0.0001). Among cortical structures, the cingulate and insular fissures were significantly deeper in CDH fetuses (p < 0.0001) as the insular depth ID was smaller in CDH (p < 0.03).

Conclusions

CDH fetuses have a smaller fronto-occipital diameter, reduced insular depth, deeper cingulate and insular fissure, and greater third ventricle width as compared to controls. These findings suggest that left CDH may have an impact on fetal brain development with an overall reduction in brain volume.  相似文献   
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