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Comparing the impacts of hiking, skiing and horse riding on trail and vegetation in different types of forest 总被引:1,自引:0,他引:1
Törn A Tolvanen A Norokorpi Y Tervo R Siikamäki P 《Journal of environmental management》2009,90(3):1427-1434
Nature-based tourism in protected areas has increased and diversified dramatically during the last decades. Different recreational activities have a range of impacts on natural environments. This paper reports results from a comparison of the impacts of hiking, cross-country skiing and horse riding on trail characteristics and vegetation in northern Finland. Widths and depths of existing trails, and vegetation on trails and in the neighbouring forests were monitored in two research sites during 2001 and 2002. Trail characteristics and vegetation were clearly related to the recreational activity, research site and forest type. Horse trails were as deep as hiking trails, even though the annual number of users was 150-fold higher on the hiking trails. Simultaneously, cross-country skiing had the least effect on trails due to the protective snow cover during winter. Hiking trail plots had little or no vegetation cover, horse riding trail plots had lower vegetation cover than forest plots, while skiing had no impact on total vegetation cover. On the other hand, on horse riding trails there were more forbs and grasses, many of which did not grow naturally in the forest. These species that were limited to riding trails may change the structure of adjacent plant communities in the long run. Therefore, the type of activities undertaken and the sensitivity of habitats to these activities should be a major consideration in the planning and management of nature-based tourism. Establishment of artificial structures, such as stairs, duckboards and trail cover, or complete closure of the site, may be the only way to protect the most sensitive or deteriorated sites. 相似文献
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本研究在运用三维荧光光谱示踪平水期东平湖DOM荧光特征的基础上,进一步分析其与氢氧同位素指标的相关性,并在此基础上尝试对大气降水的DOC贡献进行估算,以期为东平湖的污染控制及治理提供依据.结果表明,东平湖平水期DOM主要由类蛋白组分(C1和C4)和类腐殖质组分(C2和C3)构成,以类酪氨酸组分C1为主,C1所占比重将近50%.平水期东平湖DOM同时受陆源、内源及大气降水的影响,但以内源输入为主;外源输入中大气降水补给与大汶河输入所占比例相当;大气降水中的溶解性有机碳输入可能会对东平湖DOM产生不可忽视的影响,需进一步系统研究.氢氧稳定同位素与溶解态有机碳以及类腐殖质荧光之间呈显著相关关系,可以在一定程度上指示DOM的变化趋势. 相似文献
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The vegetable wastes and flower stems were co-digested to evaluate the anaerobic hydrolysis performance of difficultly biodegradable organic wastes by introducing readily biodegradable organic wastes. The experiments were carried out in batches. When the vegetable wastes were mixed with the flower stems at the dry weight ratio of 1 to 13, the overall hydrolysis rate increased by 8%, 12%, and 2% according to the carbon, nitrogen, and total solid (TS) conversion rate, respectively. While the dry weight ratio was designed as 1 to 3, there was a respective rise of 5%, 15%, and 4% in the conversion rate of carbon, nitrogen, and TS. The enhancement of anaerobic hydrolysis from the mixed vegetable wastes and flower stems can be attributed to the formation of volatile fatty acids (VFA) and nutrient supplement like nitrogen content. The maximum VFA concentration can achieve 1.7 g/L owing to the rapid acidification of vegetable wastes, loosing the structure of lignocellulose materials. The statistic bivariate analysis revealed that the hydrolysis performance was significantly related to the physical and biochemical compositions of the feeding substrate. Especially, the soluble carbon concentration in the liquid was significantly positively correlated to the concentration of nitrogen and hemicellulose, and negatively correlated to the concentration of carbon and lignocellulose in the feeding substrate, suggesting that the regulation and control of feedstock can have an important influence on the anaerobic hydrolysis of organic wastes. 相似文献
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为了达到低渗储层甲烷抽采过程甲烷采井优化设计和产能准确预测的目的,基于现场测井数据,采用非线性流体数值计算方法,以柳林煤层甲烷试验采区为例,对滑脱流动影响的煤层甲烷采场压力非线性分布和产能预测进行研究。数值计算结果表明:低渗储层甲烷运移采出受气体滑脱流动影响显著,考虑滑脱流动影响时,采场压力衰减区域变大,气体速率变快;对比测井产能历史拟合数据发现,计算所得的滑脱流动影响的产能预测值更加准确。由计算结果验证了单井开采具有采场压力影响范围较小,产能较低等缺点,并得出五采出四压裂的布井方式是既能够准确预测产能又能够更好避免井间干扰效应的最优布井方式。 相似文献
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官厅水库周边土壤重金属空间变异特征及风险分析 总被引:17,自引:3,他引:17
在官厅水库周边2~10 km范围内系统测定了8种重金属元素的含量,利用GIS技术和地统计分析方法,研究了重金属元素的空间变异特征及环境风险.结果表明,Cd是该区域主要的污染物,检测值(0.68±0.17) mg/kg相当于国家1级标准的3.4倍,40%的区域超过国家2级标准.土壤中7种重金属(Ni除外)的空间变异主要缘自于施肥、耕作及种植制度等人为活动引起的随机性因素,空间格局呈现西高东低,并呈洋河至怀来县区段污染最重的趋势.单因子污染指数和单因子生态危害系数Cd均显著高于其他重金属元素,复合污染指数呈库北高于库南,西部高于东部的空间趋势,复合生态风险指数南北向也有类似分布特征,东西向集中在怀来县、延庆县和中部北辛堡镇3个区域,说明高环境污染区将伴随高的生态风险,人口密集、工业化程度较高的城镇区域更容易引起生态危害. 相似文献
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主要探究泥浆系统中Fe2+活化过碳酸钠(SPC)降解三氯乙烯(TCE)的效果。通过批次实验研究土壤对TCE的吸附作用,并考察泥浆系统中SPC和Fe2+投加量对TCE去除效果的影响。结果表明,土壤对TCE具有一定的吸附作用;泥浆系统中,土壤含有的有机质越多,TCE去除效果越低;当SPC/TCE摩尔比为5/1~20/1时,SPC投加量对TCE去除影响不明显,TCE去除效果随Fe2+投加量增大而提高。当水土质量比为30/1,TCE初始浓度为20 mg/L时,SPC/Fe2+/TCE最优摩尔比为10/30/1,此时TCE最终去除率达到97.5%。综上所述,Fe2+活化过碳酸钠降解三氯乙烯快速高效,为应用于实际场地修复提供有效的理论依据。 相似文献
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