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131.
Carbon sequestration,biological diversity,and sustainable development: Integrated forest management 总被引:2,自引:0,他引:2
Tropical deforestation provides a significant contribution to anthropogenic increases in atmospheric CO2 concentration that may lead to global warming. Forestation and other forest management options to sequester CO2 in the tropical latitudes may fail unless they address local economic, social, environmental, and political needs of people
in the developing world. Forest management is discussed in terms of three objectives: carbon sequestration, sustainable development,
and biodiversity conservation. An integrated forest management strategy of land-use planning is proposed to achieve these
objectives and is centered around: preservation of primary forest, intensified use of nontimber resources, agroforestry, and
selective use of plantation forestry.
The information in this document has been wholly funded by the US Environmental Protection Agency. It has been subjected to
the agency's peer and administrative review and approved for publication of an EPA document. Mention of trade names or commercial
products does not constitute endorsement or recommendation for use. 相似文献
132.
Mark Appiah Dominic Blay Lawrence Damnyag Francis K. Dwomoh Ari Pappinen Olavi Luukkanen 《Environment, Development and Sustainability》2009,11(3):471-487
In Ghana, forests provide many products on which the local population subsists. However, these resources are depleting due
to a variety of factors including agricultural expansion and over-exploitation of forest resources. This paper presents an
analysis of the level of local dependence on forest resources and its implications for forest management in Ghana. The paper
also outlines the causes of continuing deforestation in the studied region from the perspective of the local residents and
discusses what role they could play in addressing the problem. The aim is to share more light on the current causes of deforestation
and make suggestions for improved community-based forest management practices that could help to reduce deforestation. Primary
data was collected through personal interviews and focus group discussions with 431 household heads randomly selected from
three Forest Districts in Ghana. The survey showed that income from agriculture constituted 60% of the average total rural
household income. Forest income provided 38% of total household income, and off-farm income 2%. The four most highly ranked
causes of deforestation are poverty-driven agriculture, lack of alternative rural wage employment other than farming, household
population levels, and conflict in traditional land practices. This shows a shift in the view of local people who in the past
were quick to blame logging companies and government policies for deforestation. The majority of the respondents depended
on wild animals like snail, bush meat, wild honey and wild and cultivated vegetables. Given the reasons for deforestation,
much thought needs to go into agroforestry practices (e.g. snail farming, bee keeping, fish farming, and vegetable production)
in efforts to reduce deforestation, which are currently less promoted.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
133.
ABSTRACT Cold chain industry has a vast potential for waste heat recovery. It is a matter of importance for energy efficiency point of view, as global energy demand is increasing day by day. Ample amount of low-grade energy is either unutilized or underutilized. The heat rejected by a Heat pump or refrigeration system emerged as a promising solution for dehydration by utilizing low-grade waste heat despite higher investment. As compared to solar drying technology, heat pump drying evolved as a reliable method regarding better process control, energy efficiency, and quality of the product to be dried. Energy utilized through the refrigeration system’s waste/exhaust heat recovery in combination with or without renewable energy source enhances the overall efficiency of the system and also reduces the cost. This useful review investigated and compared the research findings of waste heat utilization through heat pump and from condenser of refrigeration system on laboratory, pilot as well as industrial scale for drying of various fruits, vegetables, and agro products. Various drying parameters like drying rate, moisture content, Specific Moisture Extraction Rate (SMER), Coefficient of Performance (COP), Exergy efficiency, and temperature as well as humidity conditions inside the drying chamber were also reviewed to promote the technological advancement of energy utilization by commercial cold storage waste heat recovery. 相似文献
134.
Dere S Dalkiran N Karacaoğlu D Elmaci A Dülger B Sentürk E 《Environmental monitoring and assessment》2006,115(1-3):1-22
The implications of metal contamination of agricultural soils due to long term irrigation with treated industrial wastewater and their subsequent accumulation in the vegetables/crops growing on such soils has been assessed in an area of industrial complex, Jajmau, Kanpur (India). Physico-chemical properties of the soil were also studied. The soil and vegetables/crops were sampled from an area of 2100 acre agricultural land and analyzed for physico-chemical properties and metal accumulation in different parts of the plants. The comparison of the data of physico-chemical properties of control and contaminated soil showed that salinity, electrical conductivity, available phosphorous, sodium and potassium content (both water soluble and exchangeable) were found high in contaminated soil. The analysis of plant available metal content in the soil showed the highest level of Fe, which ranged from 529.02 to 2615 μg g−1 dw and lowest level of Ni (3.12 to 10.51 μg g−1 dw). The analysis of the results revealed that accumulation of toxic metal Cr in leafy vegetables was found more than fruit bearing vegetables/crops. Thus, it is recommended that the leafy vegetables are unsuitable to grow in such contaminated sites. It is important to note that toxic metal, Ni was not detected in all the plants. The edible part of the vegetables (under ground) such as, garlic (19.27 μg g−1 dw), potato (11.81 μg g−1 dw) and turmeric (20.86 μg g−1 dw) has accumulated lowest level of toxic metal, Cr than leafy and fruit bearing vegetables. In some fruit part of vegetables such as, bitter gourd, egg plant, jack tree, maize and okra, the accumulation of Cr was not detected and may be grown in this area. 相似文献
135.
Yu YX Huang NB Zhang XY Li JL Yu ZQ Han SY Lu M Van de Wiele T Wu MH Sheng GY Fu JM 《Chemosphere》2011,83(2):152-160
The concentrations of PBDEs in 299 vegetable and animal-based food samples of 31 species, collected in Shanghai, China, and the bioaccessibility of PBDEs in part of the samples were determined. The PBDE concentrations ranged from 0 to 1245.4 pg g−1 with animal-based food containing more PBDEs than vegetables. The bioaccessibility of PBDEs, determined by a method simulating human gastrointestinal digestion process, were from 2.6% to 39.9% in vegetables, and from 5.2% to 105.3% in animal-based food. For animal-based food, good correlations were observed between the bioaccessibility of PBDEs and the fat content, thus the fat content in animal-based food was able to be used to estimate the bioaccessibility of PBDEs. The total daily intake of PBDEs via ingestion of vegetables and animal-based food for an average Shanghai resident was estimated as 13 235.7 and 13 668.0 pg d−1, respectively, but the amounts available for human absorption were reduced to 2674.4 and 4316.6 pg d−1 after the PBDE bioaccessibility was considered. Finally, the contributions of different food groups to the total daily intake of PBDEs were evaluated. The results revealed that, when not considering the bioaccessibility of PBDEs, vegetables were the leading contributor (49.2%), followed by fish (34.0%). However, the sequence was reversed after the PBDE bioaccessibility was taken into account. The results indicated that human exposure to PBDEs via food ingestion might have been significantly overestimated and the exposure assessment could be misleading if the bioaccessibility of PBDEs was not considered. 相似文献
136.
Earthworm avoidance behaviour test is an important screening tool in soil eco-toxicology. This test has been developed and validated under North American and European conditions. However, little research has been performed on the avoidance test in the tropics. This work demonstrates the potential suitability of the avoidance behaviour test as screening method in the highlands of Colombia using Eisenia fetida as the bio-indicator species on contaminated soils with carbofuran and chlorpyrifos. Though for the two active ingredients 100% avoidance was not reached, a curve with six meaningful concentrations is provided. No significant avoidance behaviour trend was found for mancozeb and methamidophos. Tests were conducted in the field yielded similar results to the tests carried out in the laboratory for chlorpyrifos and mancozeb. However, for the case of carbofuran and methamidophos, differences of more than double in avoidance were obtained. Divergence might be explained by soil and temperature conditions. 相似文献
137.
Saida Barnat Michel Boisset Francine Casse Michel Catteau Jean-Michel Lecerf Daniel Veschambre 《Journal of environmental science and health. Part. B》2013,48(2):102-107
The increase of fresh vegetable and fruit (FVF) intake could contribute to the prevention of obesity and several major pathologies and thus represents a major public health goal in industrial countries. Nutritional recommendations for increased consumption of FVF could lead to ingestion of unwanted amounts of pesticides. This study was undertaken to evaluate theoretical exposure of French adults to pesticide residues under increasing amounts of FVF intake. Balanced menus with 200 – 400 – 600 – 800 and 1200 g FVF/day were established. Amounts of active substances brought by every FVF vector, at the maximum residue level (MRL) were summed up to determine the intake for each active substance. Values were compared to the Acceptable Daily Intake (ADI) to point out any potential over exposure. A maximalistic approach was adopted and no reducing factor due to processing was taken into account. It was found that under minimal recommended consumption of fruit and vegetables (400 g/d), no active substance reached the ADI, but 18 vs 144 were over 10% of the ADI. Raising FVF to 600 g/d increased the number of active substances over 10 % of the ADI to 24, but again in no case was the ADI exceeded. Doubling the intake to 800 g/d gives values over the ADI for 2 active substances only (cyhexatin and thirame). It was concluded that the increase in fruit and vegetables up to 800 g per day should not expose adults over the ADIs for a majority of authorized pesticides. In this regard, residues levels of ten active substances in fruit and vegetables should deserve particular attention. 相似文献
138.
采用大田试验研究专用叶面营养液对主要叶菜的增产效果;并以芥菜为供试叶菜系统研究了专用叶面营养液对叶菜的增产机理。结果表明;专用叶面营养液可明显促进芥菜对N、P、K养分的吸收,提高叶片硝酸还原酶活性、叶绿素含量及光合速率,增加产量和改善品质。专用叶面营养液分别优于这种营养液中的营养物质和生长调节剂。芥菜喷施专用叶面营养液,与对照相比,叶绿素含量、光合速率、硝酸还原酶活性分别增加20.2%、36%、1.201μg/(g·h);平均增产24.6%;Vc、可溶性糖分别增加87mg/kg和1.7g/kg。 相似文献
139.
Wilfredo Y. Licuanan Maricar S. Samson Samuel S. Mamauag Laura T. David Roselle Borja-del Rosario Miledel Christine C. Quibilan Fernando P. Siringan Ma. Yvainne Y. Sta. Maria Norievill B. España Cesar L. Villanoy Rollan C. Geronimo Olivia C. Cabrera Renmar Jun S. Martinez Porfirio M. Aliño 《Ambio》2015,44(8):718-736
We present a synoptic, participatory vulnerability assessment tool to help identify the likely impacts of climate change and human activity in coastal areas and begin discussions among stakeholders on the coping and adaptation measures necessary to minimize these impacts. Vulnerability assessment tools are most needed in the tropical Indo-Pacific, where burgeoning populations and inequitable economic growth place even greater burdens on natural resources and support ecosystems. The Integrated Coastal Sensitivity, Exposure, and Adaptive Capacity for Climate Change (I-C-SEA Change) tool is built around a series of scoring rubrics to guide non-specialists in assigning scores to the sensitivity and adaptive capacity components of vulnerability, particularly for coral reef, seagrass, and mangrove habitats, along with fisheries and coastal integrity. These scores are then weighed against threat or exposure to climate-related impacts such as marine flooding and erosion. The tool provides opportunities for learning by engaging more stakeholders in participatory planning and group decision-making. It also allows for information to be collated and processed during a “town-hall” meeting, facilitating further discussion, data validation, and even interactive scenario building.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0652-x) contains supplementary material, which is available to authorized users. 相似文献140.
我国野生蔬菜的开发利用 总被引:5,自引:0,他引:5
本文阐述了我国野生蔬菜的特点、利用现状及其存在的问题,提出了进一步开发利用野生蔬菜的建议. 相似文献