共查询到20条相似文献,搜索用时 171 毫秒
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在苇丛坐下,打开随身携带的《诗经》,翻到《秦风·蒹葭》。蒹葭丛中读《蒹葭》,真是亲切,就觉得是回到了诗的故乡,回到那个遥远而古老的年代。一有时候,就觉得,假日行走,若是随身携带一卷《诗经》,也许常常会在不经意间,就撞醒一个沉睡千年的美丽意象,闯进一片久蕴心头的奇妙意境,让你的旅行多一种诗意的愉悦和难以言表的快感。呱呱——唧啾,呱呱一一唧啾,……一串清脆的鸟呜,将您从酣睡中唤醒。睁开眼,窗前已是阳光灿烂。这是一个春天的假日,原计划要读读《诗经》的,何不到室外去读呢?于是操书出门,乘着和风,循着鸟声,不知不觉间,已来到一条河边。河心沙洲上,正有一对美丽的小鸟,相对而鸣。呱 相似文献
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绿色,代表希望,我们生活在美丽的大自然中,我爱绿色,爱那高大的绿色,爱那温柔的绿草,向往广阔无边的绿色草原,有活泼的小鹿与清澈的小溪陪伴。我的思绪渐渐的来到了几万年前的原始丛林中,四周静静的,不时有着绿叶伴随着清风掠"呼啦"的过我的头顶。我慢慢的闭上了眼睛,静静地听,仿佛是一位音乐家演奏着美妙的乐曲。伴随着青草与露珠的芳香,我深深的,深深的陶醉了,醉了……"嘟……!"一阵汽车喇叭声把我从人间仙境拉回了人间"地狱"。我拍了一下脑袋,定了定神,爬起床,眼前的日历:2022年1月17日。"嘟……嘟嘟……!"又是一阵刺耳的喇叭声传入耳朵。我厌恶 相似文献
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中国海滨旅游研究进展 总被引:2,自引:0,他引:2
在阅读大量相关文献资料的基础上,试图从海滨旅游兴起的原因、海滨旅游主体、海滨旅游客体及海滨旅游主客体间关系4个方面对近年来国内有关海滨旅游的研究作一系统综述.在此基础上,对中国海滨旅游以后的研究进行了展望. 相似文献
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Impacts of Camping on Vegetation: Response and Recovery Following Acute and Chronic Disturbance 总被引:3,自引:0,他引:3
Experiments with controlled levels of recreational camping were conducted on previously undisturbed sites in two different plant communities in the subalpine zone of the Wind River Mountains, Wyoming, USA. The plant communities were coniferous forest with understory dominated by the low shrub Vaccinium scoparium and a riparian meadow of intermixed grasses and forbs, of which Deschampsia cespitosa was most abundant. Sites were camped on at intensities of either one or four nights per year, for either one (acute disturbance) or three consecutive years (chronic disturbance). Recovery was followed for three years on sites camped on for one year and for one year on sites camped on for three years. Reductions in vegetation cover and vegetation height were much more pronounced on sites in the forest than on sites in the meadow. In both plant communities, increases in vegetation impact were not proportional to increases in either years of camping or nights per year of camping. Close to the center of campsites, near-maximum levels of impact occurred after the first year of camping on forested sites and after the second year on meadow sites. Meadow sites recovered completely within a year, at the camping intensities employed in the experiments. Forest sites, even those camped on for just one night, did not recover completely within three years. Differences between acute and chronic disturbance were not pronounced. 相似文献
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Nicolas Le Corre Ingrid Peuziat Louis Brigand Guillaume Gélinaud Catherine Meur-Férec 《Environmental management》2013,52(4):780-791
Disturbance to wintering birds by human recreational activities has become a major concern for managers of many natural areas. Few studies have examined how recreationists perceive their effects on birds, although this impacts their behavior on natural areas. We surveyed 312 users on two coastal ornithological sites in Brittany, France, to investigate their perception of the effects of human activities on wintering birds. The results show that the awareness of environmental issues and knowledge of bird disturbance depends on the socioeconomic characteristics of each user group, both between the two sites and within each site. Results also indicate that, whatever the site and the user group, the vast majority of the respondents (77.6 %) believed that their own presence had no adverse effects on the local bird population. Various arguments were put forward to justify the users’ own harmlessness. Objective information on recreationists’ awareness of environmental issues, and particularly on their own impact on birds, is important to guide managers in their choice of the most appropriate visitor educational programs. We recommend developing global but also specific educational information for each type of user to raise awareness of their own impact on birds. 相似文献
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Landscape ecological assessment: a tool for integrating biodiversity issues in strategic environmental assessment and planning 总被引:11,自引:0,他引:11
To achieve a sustainable development, impacts on biodiversity of urbanisation, new infrastructure projects and other land use changes must be considered on landscape and regional scales. This requires that important decisions are made after a systematic evaluation of environmental impacts. Landscape ecology can provide a conceptual framework for the assessment of consequences of long-term development processes like urbanisation on biodiversity components, and for evaluating and visualising the impacts of alternative planning scenarios. The aim of this paper was to develop methods for integrating biodiversity issues in planning and strategic environmental assessment in an urbanising environment, on landscape and regional levels. In order to test developed methods, a case study was conducted in the region of Stockholm, the capital of Sweden, and the study area embraced the city centre, suburbs and peri-urban areas. Focal species were tested as indicators of habitat quality, quantity and connectivity in the landscape. Predictive modelling of habitat distribution in geographic information systems involved the modelling of focal species occurrences based on empirical data, incorporated in a landscape ecological decision support system. When habitat models were retrieved, they were applied on future planning scenarios in order to predict and assess the impacts on focal species. The scenario involving a diffuse exploitation pattern had the greatest negative impacts on the habitat networks of focal species. The scenarios with concentrated exploitation also had negative impacts, although they were possible to mitigate quite easily. The predictions of the impacts on habitats networks of focal species made it possible to quantify, integrate and visualise the effects of urbanisation scenarios on aspects of biodiversity on a landscape level. 相似文献
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State of the environment reporting (SoER) is a well-established and widely applied environmental management tool in the South African context. Despite a wealth of knowledge about conducting and preparing SoERs, there is a paucity of research on the effect SoER has had on decision-making at the local government sphere. This study investigated the effect of SoER on decision-making for a sample of municipalities in the Gauteng Province of South Africa. The methodology relied on interviews with key role players, which include the ‘‘environmental function’' as well as ‘‘other functions’' responsible for infrastructure development and planning within the municipalities. The results show that notwithstanding the extensive time and resources spent on SoER, it appears to have had a limited effect on decision-making, especially beyond the environmental function. Recommendations to improve the influence of SoER on decision-making in developing countries include improved clarity on the purpose and home of SoER within municipalities, adequate budget and capacity, and effective cooperative governance both within the municipalities, and with other spheres of government. 相似文献
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大气氮沉降增加是全球变化的重要现象之一,草原生态系统对氮沉降增加的响应成为草地生态学的研究热点之一。凋落物分解是草原生态系统养分循环和能量流动的主要途径,氮沉降增加引起草原植物群落结构变化,导致凋落物质量、土壤肥力、土壤微生物和土壤动物的变化,最终影响凋落物的分解。本文综述了氮沉降对草原凋落物结构、化学组成和分解环境的影响等方面的国内外最新研究进展,讨论了需进一步加强研究的内容,以期为进一步拓展该领域研究的广度和深度、为全面分析和评估全球变化对草原生态系统的影响提供参考。 相似文献
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M. A. Arthur G. B. Coltharp D. L. Brown 《Journal of the American Water Resources Association》1998,34(3):481-495
ABSTRACT: Forest land managers are concerned about the effects of logging on soil erosion, streamflow, and water quality and are promoting the use of Best Management Practices (BMPs) to control impacts. To compare the effects of BMP implementation on streamwater quality, two of three small watersheds in Kentucky were harvested in 1983 and 1984, one with BMPs, the other without BMPs. There was no effect of clearcutting on stream temperatures. Streamflow increased by 17.8 cm (123 percent) on the BMP watershed during the first 17 months after cutting and by 20.6 cm (138 percent) on the Non-BMP watershed. Water yields remained significantly elevated compared to the uncut watershed 8 years after harvesting. Suspended sediment flux was 14 and 30 times higher on the BMP and Non-BMP Watersheds, respectively, than on the uncut watershed during treatment, and 4 and 6.5 times higher in the 17 months after treatment was complete. Clearcutting resulted in increased concentrations of nitrate, and other nutrients compared to the uncut watershed, and concentrations were highest on the non-BMP watershed. Recovery of biotic control over nutrient losses occurred within three years of clearcutting. The streamside buffer strip was effective in reducing the impact of clearcutting on water yield and sediment flux. 相似文献
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Alfonso Balmori 《The Environmentalist》2010,30(1):90-97
A review on the effects of radiofrequency radiation from wireless telecommunications on living organisms and its possible
impact on wild mammals are presented. Physical and technological characteristics of mobile telephone and phone masts, the
scientific discoveries that are of interest in the study of their effects on the wildlife, action mechanisms on biological
systems and experimental difficulties are described. Keeping in mind that electromagnetic pollution (in the microwave and
radiofrequency range) is a possible source for decline of some mammal populations, it is of great importance to carry out
studies on the effects of this new pollutant to wildlife. Some research types that could be useful to determine adverse health
effects are proposed. 相似文献
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Spatial Targeting of Agri-Environmental Measures: Cost-Effectiveness and Distributional Consequences
Sandra Uthes Bettina Matzdorf Klaus Müller Harald Kaechele 《Environmental management》2010,46(3):494-509
Agri-environmental measures are payments to farmers to reduce environmental risks or to preserve cultivated landscapes. These
measures are codified in European Union regulations. Poor spatial targeting is one of the major causes of low cost-effectiveness
in agri-environmental measures. Existing studies on spatial targeting focus primarily on selected individual measures; hence,
they do not allow for conclusions at the program level, where the planning and implementing of decisions on a number of different
measures has to be made. In this study, we analyzed the impacts of two spatial targeting options (targeting of erosion-reducing
measures on erosion vulnerable areas; targeting of grassland extensification on N-pollution vulnerable areas) on the cost-effectiveness
of the single measures and the entire agri-environmental program of the federal state of Brandenburg in Germany. The methodological
steps included an analysis of empirical data on land use and program participation, an expert-based environmental impact assessment
and a spatial allocation procedure based on linear programming. The environmental impact assessment delivered goal-specific
index values for each measures-land parcel combination expressing the suitability of the measures for contributing to four
regionally relevant program objectives. The cost-effectiveness of the measures and the program were calculated by putting
budgetary costs in relation to the achieved environmental index sum. The calculated cost-effectiveness of the program in 2006
was 89.6% of the simulated optimal cost-effectiveness. The spatial targeting of erosion-reducing measures on erosion vulnerable
areas caused an increase in the cost-effectiveness at the measures level and almost no changes at the program level. The spatial
targeting of grassland extensification on N-pollution vulnerable areas, despite also improving the cost-effectiveness of this
measure, had negative effects on the cost-effectiveness of the program. 相似文献