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321.
Sepiolite and biochar can immobilize heavy metals and organic pollutants in soil effectively, but their impact on the soil microbial community and diversity is still unclear. High-throughput Illumina MiSeq method was used to study the effects of sepiolite and biochar on the diversity of microbial communities in acid red soil amended with cadmium and atrazine. A total of 47,472 microbiological Operational Taxonomic Units (OTUs) were found in all the treated soil samples. Sepiolite and biochar enriched the diversity of soil microbes at different classification levels and OTUs, but the effect of biochar was stronger than that of sepiolite. A Venn diagram showed that compared with other treatments, adding 2% biochar could promote the growth of specific microbes, which is better than the case for 5% biochar. The heat map of species abundance cluster showed that the dominant microbes in soil were different for different treatment doses of sepiolite and biochar. Among all the soil treatments, the top ten dominant bacterial phyla (from high to low dominance) were: Actinobacteria, Proteobacteria, Firmicutes, Bacteroidetes, Acidobacteria, Gemmatimonadetes, Chloroflexi, Planctomycetes, Cyanobacteria­, and Verrucomicrobia. The addition of sepiolite and biochar promoted the restoration of the microbial community diversity in contaminated soil.  相似文献   
322.
Large quantities of herbicides are used on agricultural soils, but the effects of herbicides on the structure of the soil microbial community have not been well investigated. In this study, soil from three soybean fields was investigated. The herbicide imazethapyr was applied in one year to soil 1 and in two sequential years to soil 2. Control soil received no imazethapyr. Microbial biomass and community structure were characterised using chloroform fumigation–extraction and phospholipid fatty acid (PLFA) determination. The imazethapyr residue was 1.62 μ g·kg?1 in soil 1 and 1.79 μ g·kg?1 in soil 2. The microbial biomass carbon and total PLFAs for soil 2 were much higher than for the other soils. PLFA profiles showed that fatty acids for Gram-negative and Gram-positive bacteria, as well as total bacteria and total fungi in soil 2 were higher than in other samples. Principal component analysis of the PLFAs showed that the structure of the microbial community differed substantially among the three different soybean field soils. Application of the herbicide imazethapyr to soybean fields clearly changed the soil microbial biomass and shifted the structure of the microbial community.  相似文献   
323.
SUMMARY

This paper focuses on efforts to promote environmental education and community mobilization around environmental issues in Hong Kong. It is primarily concerned with efforts directed at the broader community (i.e. the population as a whole) rather than with environmental education through formal school and college curricula. The paper draws on a recently completed study commissioned by the Environmental Campaign Committee, the principal source of financial support for such efforts undertaken by environmental NGOs, community groups and educational institutions in Hong Kong. The study examined how and to what effect the Committee had used its financial resources between 1994–1999. It also examined international experience with a view to recommending changes in the overall approach to environmental education and community mobilization initiatives and their funding in Hong Kong.

The paper suggests that the existing approach to community-wide environmental education and its funding in Hong Kong have suffered from various weaknesses, most notably the absence of an integrated and goal-oriented strategy, an over-reliance on a ‘top-down’ campaign-based approach, a failure to establish explicit linkages with the concept of sustainable development and to ground initiatives at the local neighbourhood and community levels, and a preoccupation with the financial inputs provided to support this work at the expense of effective monitoring and auditing of project outputs and benefits.  相似文献   
324.
SUMMARY

In recent years, indigenous tenure over forest lands has emerged as a means to conserve forests while recognizing indigenous rights. There is concern, however, that indigenous reserves may not be an appropriate policy tool for sustained forest conservation. Our research examined how recognition of indigenous common-property rights has controlled agricultural expansion and conserved forests in Bosawas Biosphere Reserve, Nicaragua. We used satellite imagery with empirical data gathered in the field on land-use institutions, population pressures, and land-use practices to compare whether indigenous communities under territorial management or public management are better able to (1) control the ‘fast threat’ of frontier expansion and (2) address the long-term ecological threats posed by indigenous land-use practices and institutional changes in the region. Our findings are that indigenous residents who share common-property rights over their territories are better able to control agricultural expansion than are indigenous residents living on public lands. With respect to the long-term threats to the region, a series of simulations of possible land-use pressures demonstrate that the enforcement of territorial boundaries and further development of indigenous forest management rules will prove crucial in determining land-use capacity and deforestation over the next 50 years.  相似文献   
325.
ABSTRACT

This article contributes to efforts to validate a common set of parameters and principles of sustainable agriculture. Comparisons between alternative forms of sustainable agriculture and rural-to-urban community resilience are investigated. Conclusions are drawn between multiple sustainable/alternative agriculture systems and evaluated. A set of common baseline parameters and principles is proposed as a method of evolving a common structural framework for strengthening sustainability of agriculture and rural contexts. Concepts of rural-to-urban community sustainability are proposed, supporting sustainable agriculture contexts as rural and urban. In the twenty-first century, agriculture is becoming more diversified and less typified as a rural occupation. Urban agriculture is expanding as the need for fresh, affordable, accessible agriculture produce increases in urban areas. Evidence supports symbiotic relationships between sustainable agriculture and rural/urban communities, although some claim this relationship has not been clearly defined.

This article investigates sustainable agriculture from two perspectives. We ask ‘what are common parameters and principles of the various forms of sustainable agriculture,’ and ‘why urban-to-rural context.’ Organic agriculture parameters and principles are proposed as a conceptual framework toward establishing baseline parameters and principles for sustainable agriculture. Best management parameters of urban and rural sustainable agriculture in the United States and the United Kingdom are examined for their potential to develop a strengthening framework of parameters and principles of agriculture and rural-to-urban sustainability. These results are compared and evaluated for their effectiveness in redefining current sustainable agriculture practices, and their value in strengthening sustainable agriculture symbiosis with rural-to-urban community systems.  相似文献   
326.
SUMMARY

An approach to the rehabilitation of degraded community lands built on people's perceptions and traditional knowledge was developed, implemented on a small scale (6 ha plot), and evaluated in terms of economic and ecological costs and benefits over a period of 5 years in a mid-altitude (1200 m) village of Garhwal Himalaya. Rehabilitation comprised establishment of water harvesting tanks, organic management of soil, agroforestry (native multipurpose trees t traditional crops), and decision making by the whole village community. Costs and benefits under irrigated and unirrigated conditions were compared. The total cost of establishing the irrigated agroforestry system was 1.23 fold that of the unirrigated one, whereas the total benefit was 2.09 fold. The average standing above-ground biomass of the 4-year-old plantation in the irrigated agroforestry system was 11.69 t/ha compared to 8.34 t/ha in the unirrigated system. Improvement in soil properties was more pronounced in the irrigated system than in the unirrigated one. Nutrient input, an input derived largely from forest biomass, in the unirrigated system was nearly 3 times higher than that in the irrigated system. It is concluded that, considering the local and national/regional/global interests in an integrated manner, agroforestry incorporating water management would be a more effective option for rehabilitating degraded community lands than the afforestation currently being attempted by the government in the mid-altitudes of Indian Himalaya.  相似文献   
327.
为探讨不同轮作制度下长期施肥对冬小麦Triticum aestivum L.田间杂草及小麦生长的影响,我们在三个长期田间肥效试验定位点,研究3种轮作制度下(冬小麦-大豆Glycine max (L.) Merr.(WS)、冬小麦-夏玉米Zea Mays L.(WM)、冬小麦-中稻Oryza sativa(WR))长期不同施肥模式对冬小麦田间杂草群落及小麦生长的影响.研究表明,在3种轮作制度下,平衡施加N、P、K肥或者NPK肥配施有机肥均可以显著降低冬小麦田杂草密度、地上生物量和田间光照透过率,促进冬小麦生长,并提高冬小麦产量和地上生物量;而且在冬小麦-大豆轮作和冬小麦-中稻轮作的冬小麦田中平衡施加N、P和K肥可以在控制杂草密度的同时保持一个较均一的杂草群落.3种轮作制度下各指标相对值比较发现,3种轮作制度改变施肥对冬小麦田间光照透过率影响程度的顺序与3种轮作制度改变冬小麦田中施肥对杂草密度和地上生物量影响程度的顺序相同;另外,在冬小麦-大豆轮作和冬小麦-中稻轮作制度下杂草密度与冬小麦田间光照透过率之间的相关系数也很高(R≥0.7906),说明施肥对冬小麦田间光照透过率的改变可能是施肥影响冬小麦田间杂草群落的主要途径之一.轮作制度改变冬小麦田中施肥对优势杂草种类数和杂草生物多样性影响的程度差别不大,这可能是因为轮作改变施肥对田间杂草的影响并没有达到引起田间杂草物种消亡的程度.结果表明,在3种轮作制度中施肥对冬小麦田间杂草群落及小麦生长的影响虽有差异,但都显示出施肥在抑制田间杂草发生、维持杂草生物多样性和提高作物产量上的作用.  相似文献   
328.
《Environmental Hazards》2013,12(2):103-121
If community disaster resilience is to mature into a robust and lasting area of research, methodologically facilitated dialogue between empirical observations and theory is necessary. However, methodological and empirical research has outpaced community disaster resilience theory. To address this gap, a theoretical framework called WISC is presented. WISC is named after four constructs of the framework: well-being, identity, services, and capitals. WISC relates the two concepts of community and infrastructure, broadly defined, to the four constructs it is named after. The 4 constructs are respectively defined by 29 variables. The broadest interpretation of WISC is that infrastructure supports and facilitates components of community within human settlements. Infrastructure is represented as combinations of capitals and services; community is represented by connections of identity and well-being. Ultimately, well-being of a community is dependent on that community's collective capital. But these two constructs are mediated by the intervening constructs of identity and services. WISC goes beyond existing frameworks by addressing essential elements of theory building that have been overlooked in the literature, while synthesizing other frameworks and areas of knowledge. WISC provides a powerful foundation for posing and evaluating hypotheses, improving data collection efforts, and, most importantly, enabling critical theory building.  相似文献   
329.
《Environmental Hazards》2013,12(3):222-232
The coast has always been an area of significant hazards. In situations of community self-sufficiency, consequences of coastal hazards might be isolated to regions directly affected by the hazard. But, in the current global economy, fewer and fewer communities are isolated; damage to one location frequently has consequences around the globe and coastal community resilience can have broad-reaching benefits. Hazard responses for the built coastal environment have typically been resistance: constructing stronger buildings, enhancing natural barriers or creating artificial barriers. These approaches to hazard reduction through coastal engineering and shoreline defence efforts have been crucial to sustained coastal development. However, as coastal forces continue or magnify and resources become scarcer, resistance alone may be less effective or even unsustainable, and interest in resilience has grown. Resilience is a community's ability either to absorb destructive forces without loss of service or function, or to recover quickly from disasters. Community resilience encompasses multiple elements, ranging from governance to structural design, risk knowledge, prevention, warning systems and recovery. This paper focuses on hazards of coastal communities, and provides a review of some recent engineering efforts to improve the resilience elements of risk knowledge and disaster warnings for coastal disaster reduction.  相似文献   
330.
黄余春  田昆  岳海涛  杨扬 《生态环境》2012,21(2):359-363
湿地植物具有净化水质的特殊功能,研究不同湿地植物群落对生活污水净化效果及机理,对退化湿地的恢复与人工湿地的构建具有重要的理论和现实意义。选取小黑三棱+杉叶藻+荇菜(Com.Sparganium simplex+Hippuris vulgaris+Nymphoidespeltatum)、水葱+睡菜+荇菜(Com.Scirpus validus+Menyanthes trifoliate+Nymphoides peltatum)、菰+荸荠+荇菜(Com.Zizaniacaduciflora+Heleocharis yunnanensis+Nymphoides peltatum)和香蒲+睡菜+眼子菜(Com.Typha przewalskii+Menyanthestrifoliate+Potamogeton distinctus)等4种云南高原常见湖滨湿地植物群落作为实验材料进行水质净化模拟研究。结果表明:供试植物都能较好的适应生活污水环境,各植物全株氮质量分数在12.37~19.55 mg.g-1之间,各群落植物氮累积量为229~269 mg.m-2,对生活污水脱氮贡献率为10.11%~11.21%;各群落对生活污水TN的去除率都在75%以上,均显著高于无植物对照组(P〈0.05),其中水葱+睡菜+荇菜(Scirpus validus+Menyanthes trifoliate+Nymphoides peltatum)群落对生活污水TN去除效果显著优于其他3种群落(P〈0.05),去除率高达(93.79±1.27)%;试验期间,各群落污水N03--N与TN浓度之间显著负相关(r=–0.597,P〈0.05),能很好的揭示氮的去除过程;各群落植物净增生物量与群落TN累积量显著正相关(r=0.953,P〈0.05),表明收割植物可充分发挥湿地植物的脱氮潜力;植物群落能有效增强和促进湿地系统对污水中氮的净化能力,各植物群落对污水TN去除贡献率在29.24%~43.57%之间,群落内植物生长特性及其种间关系是各植物群落水质净化效果存在显著差异的主要原因。  相似文献   
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