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231.
微塑料广泛分布在土壤环境中,威胁着土壤生态环境系统,改变了土壤理化性质和微生物特征.生物炭因其特殊的孔隙结构具有良好的土壤养分保持能力,常被作为改善土壤质量的土壤改良剂.然而,目前关于生物炭施用对微塑料污染土壤理化性质和细菌群落的影响及其机制研究还非常有限.因此,进行为期21 d微观土壤培养实验,利用16S rRNA高通量测序技术分析生物炭的施用对不同浓度微塑料污染土壤理化性质和细菌群落变化的影响.结果表明,生物炭的施用减缓了微塑料污染土壤硝态氮和速效磷含量的降低,增加了全磷含量.生物炭的添加增加了微塑料污染石灰性土壤酸杆菌门(Acidobacteriota)、放线菌门(Actinobacteriota)和拟杆菌门(Bacteroidota)等微塑料耐受菌门相对丰度.在第7 d和第21 d各处理的优势细菌为变形菌门(Proteobacteria)、酸杆菌门和放线菌门.与第7 d相比,第21 d各处理土壤变形菌门和厚壁菌门(Firmicutes)的相对丰度显著降低,酸杆菌门、放线菌门、拟杆菌门、绿弯菌门(Chloroflexi)和粘菌门(Myxococcota)的相对丰度增加.施用生物炭...  相似文献   
232.
The various indigenous uses and structure of chir pine forests were studied in Uttaranchal state of the Indian Republic. A questionnaire survey was conducted in 50 villages of Uttaranchal to gather information on the indigenous uses of chir pine. For the study of community composition and structure of chir pine forest, at least 15 quadrats of 10 x 10 m were selected randomly across various localities, and the number of individuals, along with other dominant tree and shrub species, were enumerated in each quadrat. About 10 indigenous uses of chir pine were prominent in Uttaranchal. Besides resin, an important non-wood product, different parts of chir pine, such as cones, trunk, stems, wood, leaves and bark, were used by the local people. Chir pine is a subject of the folklore and mythology of indigenous cultures in Uttaranchal. Chir pine forest formed three major communities in Uttaranchal viz., sal-pine (Shorea robusta-Pinus roxburghii), pine pure stands and oak-pine (Quercus leucho-trichophora-Pinus roxburghii). These communities sustained various multiple-use trees and shrubs along with various edible mushrooms (eg. Agaricus campestris, Morchella esculenta and Sparassis crispa). The results of this study are discussed in the light of chir pine conservation and management policies.  相似文献   
233.
ABSTRACT

Rural communities worldwide face a decrease of critical ecosystem services caused by replacement of native forests by commercial plantations. Replacement of native forest by commercial plantations decreases water provisioning, with possible negative impacts over well-being. We tested this hypothesis in Central Chile. We assessed subjective well-being (SWB) and local perceptions of changes in forest cover and water provision among 78 rural families. We also assessed if the Shifting Baseline Syndrome (SBS) affects the perceptions of environmental changes and their implications in SWB. Individuals perceived less forest cover than 20 years ago, and this is seen as a factor of decreased livelihood, availability of forest products, and water provisioning for households. People also reported less water available than 20 years ago. The main drivers associated with decreased water provision were the establishment of pine plantations (44% of individuals) and drought (44%). A better-off SWB was associated with perception of lower rate of deforestation. The perceptions of forest degradation and its association to SWB are affected by SBS. Paradoxically, a better-off SWB was also associated with an improvement of water quality, although the quantity and quality of water have decreased according to biophysical data, which ought to decrease the SWB. Impacts of environmental degradation in SWB are masked by factors such as more infrastructure for drinking water, assisted by governments. This masking of environmental degradation reduces the opportunity to avoid negative impacts over well-being among rural communities that are dependent on assistance around the world.  相似文献   
234.
《Environmental Hazards》2013,12(2):197-214
Tropical Cyclone Monica is one of the most intense Australian cyclones in recorded history, and threatened several Indigenous communities in April 2006. It prompted the evacuation of the remote island community of Warruwi, and caused considerable damage to the mainland township of Maningrida. The evacuation of Warruwi went smoothly as emergency services personnel, the community and the airline cooperated to airlift some 350 people to designated safe areas on the mainland. We show that local institutions culturally embedded in Indigenous ways of understanding and responding to the world were important in providing essential but ‘unofficial’ services during the emergency. Recognizing and respecting the resilience of the local process involved in everyday Indigenous life is revealed as central to ensuring local cooperation and effective involvement of state and national institutions in delivering effective measures during emergencies. Ensuring that local, state and national authorities offer recognition and understanding of these Indigenous institutions, and develop strong relationships with them, should be a priority in developing approaches that limit conflict and trauma where emergency services risk overriding local protocol.  相似文献   
235.
The benefits of indigenous knowledge within disaster risk reduction are gradually being acknowledged and identified. However, despite this acknowledgement there continues to be a gap in reaching the right people with the correct strategies for disaster risk reduction.

This paper identifies the need for a specific framework identifying how indigenous and western knowledge may be combined to mitigate against the intrinsic effects of environmental processes and therefore reduce the vulnerability of rural indigenous communities in small island developing states (SIDS) to environmental hazards. This involves a review of the impacts of environmental processes and their intrinsic effects upon rural indigenous communities in SIDS and how indigenous knowledge has contributed to their coping capacity. The paper concludes that the vulnerability of indigenous communities in SIDS to environmental hazards can only be addressed through the utilisation of both indigenous and Western knowledge in a culturally compatible and sustainable manner.  相似文献   
236.
The integrity of the relationship between humanity and nature is fundamental to the health and survival of our species. Humans have always required knowledge and understanding of the planet’s life-supporting systems. Such knowledge and understanding form the basis of ecological literacy which, we suggest, is fundamental to the sustainability of human settlements. An assessment of South Australian adults showed positive correlations between ecological literacy and a number of socio-demographic and psychographic factors. An analysis of the most and least eco-literate individuals within a sample of over 1000 adults revealed significant distinguishing characteristics. Our findings indicate that high ecological literacy is strongly correlated with gender, age, education (and in particular, science-based education), employment status, engagement with nature both as children and adults, growing food, outdoor experiences and lifestyles, growing up in small communities and relational learning. In contrast, low ecological literacy is associated with a different set of socio-demographic and psychographic characteristics such as lower levels of education, growing up in large urban communities, and spending little time outdoors or in natural settings. In addition, perceptions about the major contributors to ecological knowledge and understanding were markedly different within the two groups. These patterns of difference between those with high and low ecological literacy among South Australian adults invite serious consideration for a society that aspires to cultivate an informed citizenry with capacity for making effective environmental decisions.  相似文献   
237.
以入太湖莲花荡水系为研究对象,结合2015年4个季度9个采样点的水质学、生物学共7个指标生态调查数据,采用多指标综合评价法,从生物完整性、化学完整性2个方面评价了莲花荡水系整治工程前后的生态健康状况。结果表明,2015年第1、2季度健康状况较差,健康的样点个数分别为3和1,在2015年6月开展清淤工程及集约化畜禽产业整改后,3、4季度健康状况明显改善,健康样点个数分别达到9和7。影响莲花荡水系化学完整性的主要水质指标是TN、TP,3、4季度TN仍超出地表水Ⅴ类标准,处于严重病态,TP为地表IV类标准,处于病态。影响莲花荡水系生物完整性的主要因子是底栖动物,仅监测到20种耐污能力较高的底栖动物物种,而未发现清洁物种。为了进一步改善莲花荡水系生态健康状况,建议开展沿岸农村生活污水的截污治理、农业面源的生态拦阻等污染源控工程,辅以生态岸带建设及湖滨带生态修复等工程。  相似文献   
238.
以流动人口聚居区为研究对象,构建流动人口聚居区人居环境市民化评价指标体系,评价北京市典型流动人口聚居区的人居环境市民化程度,分析流动人口聚居区人居环境市民化的类型分异特征,并在研究基础上提出不同空间类型流动人口聚居区人居环境市民化的提升路径。结果表明:流动人口聚居区人居环境市民化进程呈“由近及远”的圈层式空间推移过程,并高度依赖于土地城市化水平;流动人口聚居区人居环境市民化存在显著的类型分异。据此,提出近郊城中村型、近郊城市住宅型和远郊城中村型3类流动人口聚居区应分别采取重建提升模式、优化提升模式和存续提升模式,以高效、有针对性地提升流动人口聚居区人居环境,缩小流动人口与本地户籍人口的人居环境差距,实现流动人口市民化的发展目标。  相似文献   
239.
ABSTRACT: Benthic invertebrate faunas were compared to two fifth-order streams, the Atigun River flowing northward and the Dietrich River flowing southward. Sixty-eight taxa were collected, forty-nine from each stream. Aquatic insects comprised 88% of the taxa and 97% of the individuals from the Dietrich River and 73% of the taxa and 97% of the individuals from the Atigun River. Diptera, especially Chironomidae, were most abundant. Plecoptera, Ephemeroptera, Oligochaeta, Acarina, and Collembola were significant. In both streams the headwaters were dominated by the subfamily Diamesinae which was replaced by Orthocladiinae downstream. Diversity seemed to increase with stream order. Cluster analysis showed a high degree of resemblance between the benthic faunas of the rivers. Faunal resemblance decreased with increasing distance between stations, both within and between the streams. Although some taxa may occur in only one stream, the evidence for faunal resemblance is stronger than for faunal differences. Other studies have shown that differences in total radiation associated with valley aspect affect local climate, hydrology, and distribution of terrestrial plants and animals. However, the benthic faunas of Atigun and Dietrich Rivers were remarkably similar. Factors which operate independently of aspect, possibly freezing solid in winter, may control the occurrence of species in these streams.  相似文献   
240.
The interrelationship of society and environment is addressed here through the study of a remote fishing village of 750 people. An interdisciplinary study evaluated demographic, economic, and social aspects of the community, and simulation modeling was used to integrate these societal characteristics with environmental factors.The population of the village had grown gradually until the 1960's, when a decline began. Out-migration correlated with declining fish harvests and with increased communications with urban centers. Fishing had provided the greatest economic opportunity, followed by logging. A survey was conducted to investigate the costs and revenues of village fishermen. Diversification characterized the local fleet, and analysis showed that rates of return on investment in the current year were equal between vessel types.The variable levels and rate parameters of the demographic, economic, and social components of the model were specified through static and time series data. Sensitivity analysis to assess the effects of uncertainty, and validation tests against known historical changes were also conducted. Forecast scenarios identified the development options under several levels of fish abundance and investment. The weight given to ecological versus economic resource management registered disproportionate effects due to the interaction between investment and migration rates and resource stochasticity. This finding argues against a golden mean rule for evaluating policy trade-offs and argues for the importance of using a dynamic, socio-ecological perspective in designing development policies for rural communities.  相似文献   
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