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71.
旅游环境舒适度评价及其时空分异——以杭州西湖为例   总被引:1,自引:0,他引:1  
旅游环境舒适度是影响旅游者出行决策和消费行为的重要因素,进一步影响到目的地适游期长短和旅游设施利用率。影响旅游舒适度的因素主要包括气候与环境两方面。以杭州西湖景区为研究对象,尝试将影响舒适度的空气质量、噪音等环境因素与气候因素共同纳入评价体系,选取温度、相对湿度、二氧化碳、一氧化碳、噪音5项指标和6个代表性检测点,进行为期1a定时定点检测,在排除二氧化碳与一氧化碳影响的基础上,构建了旅游环境舒适度评价模型,研究景区尺度存在的旅游环境舒适度时空分异特征。研究发现:不舒适时段主要集中在1月上旬到2月下旬,舒适和较舒适时段主要集中于2月下旬到7月中旬、8月下旬到11月下旬;山区与湖区各项环境指标要优于近城区、游客集聚区及交通繁忙区,平均舒适度山区(1.30)湖心区(1.66)城区(1.82)近城区(2.02)游人集聚区(2.47)交通繁忙区(2.48)。6个观测点在不同时段表现的舒适度差异也不同,差异最大的时段出现在4月中旬到5月中旬,差异最小时段出现在1月上旬到2月下旬。温湿度与噪音存在反向协同作用,引起环境舒适度变化。温湿度舒适时段往往旅游活动频繁,导致噪音升高降低了旅游环境舒适度。温湿度不舒适期旅游活动减少使得声环境相对舒适。  相似文献   
72.
张翼然  周德民  刘苗 《生态学报》2015,35(13):4279-4286
湿地生态系统为人类生存和发展提供了多种服务功能,不仅包括水资源、水产品等直接输出功能,还包括调蓄洪水、净化水质、调节大气成分等调节服务功能和文化服务功能。通过对已经发表湿地生态系统服务功能价值评价相关的文献进行搜集和整理,得到全国71个湿地案例点的价值评价数据,在此基础上对湿地生态系统各项服务功能在全国各区域的生态系统价值量进行对比分析。全国湿地价值评价结果显示,按照各项服务功能按照价值量高低排序依次为调节气候调蓄洪水涵养水源净化水质保持土壤产品输出固碳释氧生物栖息地旅游休闲科研教育。在对全国湿地进行分区分析得知,东北平原及山区、东部地区和青藏高原地区在各项调节、供给服务功能方面发挥着显著的积极作用,这3个区域同时也是我国湿地的密集分布区。结合不同地理分区下的湿地生态系统服务功能价值量特点,可以实现区域发展与湿地生态环境研究的协同发展,并能够为湿地的保护和建设起到科学、合理的参考方案。  相似文献   
73.
鄱阳湖溶解态重金属空间分布格局及风险评估   总被引:3,自引:0,他引:3  
张大文  张莉  何俊海  罗林广  魏益华 《生态学报》2015,35(24):8028-8035
采用ICP-MS定量研究了鄱阳湖溶解态重金属As、Cd、Cr、Cu、Pb和Zn空间分布特征,并对其引起的健康风险进行了评价。结果表明,鄱阳湖溶解态As、Cd、Cr、Cu、Pb和Zn的水平均符合国家Ⅰ、Ⅱ类饮用水质标准;鄱阳湖溶解态重金属的空间分布格局为As和Cr在整体上呈现北部大于南部,Cu为北部和南部高,中部低,Pb和Zn均呈现南部大于北部,而Cd的空间分布规律不明显。风险评估结果显示,鄱阳湖As、Cd、Cu、Pb和Zn的风险水平小于国际辐射防护委员会(International Commission on Radiation Protection;ICRP)的推荐值(5×10~(-5)a~(-1)),但是Cr的风险水平(4.74×10~(-5)a~(-1))接近了ICRP推荐值,且由As、Cd、Cr、Cu、Pb和Zn引起的健康总风险达到了5.88×10~(-5)a~(-1),超过了ICRP推荐值。鄱阳湖由Cr和As引起的健康风险之和占总风险比例达到99.72%,是主要的健康污染物,需引起风险决策部门的重视。  相似文献   
74.
Age and growth characteristics of the thin-lipped Grey Mullet (Liza ramada) were investigated in three North African wetland lakes: Merja Zerga (Morocco), Garâat Ichkeul (Tunisia) and Edku Lake (Egypt). Age structure of the mullet populations was very similar in all three study lakes. Small differences in growth were indicated, especially for the Moroccan population, where growth tended to be slower than for the other two populations. The fastest growth was observed in the Edku population while the best condition was observed in the Ichkeul population. Compared with some European populations, the sampled North African populations have faster growth and better condition factors.  相似文献   
75.
王瑾杰  丁建丽  张喆 《生态学报》2019,39(5):1784-1794
传统的土壤水分模拟研究难以从土壤水分变化的时空双向出发表达其连续演变的过程,存在时空尺度效应问题。借助SWAT模型模拟的长时间序列优势,结合高分辨率卫星影像和遥感技术,力图在时空尺度效应问题上取得突破。并利用长时间序列的模拟结果分析流域土壤水分的空间格局和不同维度时空异质性。结果表明:(1)2008-2014年间艾比湖流域土壤水分主要受气温、降水及人类活动影响,呈波动变化,总体偏低且具有逐年减小趋势。(2)受降水、地形及土地覆被影响,土壤水分分布呈现出由山区向两侧平原减少的特点,且林地 > 农用地 > 草地 > 稀疏植被。(3)近10年间土壤水分低值区由原来的北部山区及平原向东部、东南部平原区及南部山区迁移,东部减少最为明显。(4)流域四季土壤水分变化差异显著。其中,春季主要受融雪影响;夏季、秋季主要受降雨量和气温影响;冬季主要受固态降雪和气温影响;且不同年份、相同季节、相同子流域土壤水分变化趋势表现一致。  相似文献   
76.
Few comparisons exist between vertical accretion (VA) and carbon accumulation rates (CARs) in restored versus historic (i.e. reference) marshes. Here, we compare these processes in a formerly diked, sparsely vegetated, restored salt marsh (Six Gill Slough, SG), whose surface is subsided relative to the tidal frame, to an adjacent, relatively pristine, historic salt marsh (Animal Slough, AS). Six sediment cores were collected at both AS and SG approximately 6 years after restoration. Cores were analyzed for bulk density (BD), % loss of ignition, % organic carbon, and 210Pb. We found that sharp changes in BD in surface layers of SG cores were highly reliable markers for the onset of restoration. The mean VA since restoration at SG (0.79 [SD = 0.29] cm/year) was approximately twice that of AS (0.41 [SD = 0.16] cm/year). In comparison, the VA at AS over 50 years was 0.30 (SD = 0.09) cm/year. VA consisted almost entirely of inorganic sediment at SG whereas at AS it was approximately 55%. Mean CARs at SG were somewhat greater than at AS, but the difference was not significant due to high variability (SG: 81–210 g C m?2 year?1; AS: 115–168 g C m?2 year?1). The mean CAR at AS over the past 50 years was 118 (SD = 23) g C m?2 year?1. This study demonstrates that a sparsely vegetated, restored salt marsh can quickly begin to accumulate carbon and that historic and restored marshes can have similar CARs despite highly divergent formation processes.  相似文献   
77.
After alteration in the pattern of drainage of run-off from the surrounding swamps and changes in the colour and transparency of the Lake Glubokoe water, the previously epilimnial Trichocerca similis, Conochilus unicornis and Keratella cochlearis showed a shift of their maximum numbers to deeper layers. Pompholyx sp. and Trichocerca capucina, which are regarded as indicators of eutrophic waters, have disappeared from the pelagic zone of the lake and Conochilus hippocrepis, Synchaeta pectinata, Gastropus stylifer, Asplanchna herricki, Ascomorpha ecaudis, Ascomorpha saltans, Euchlanis dilatata and Trichocerca porcellus have made their appearance. Most of the new species are considered to be indicators of oligotrophic conditions. However the total density of pelagic rotifers remained at the same level. Apparently the establishment of the new species of rotifers was possible due to some ‘rarefaction’ of the epilimnion, the disappearance of predaceous Mesocyclops leuckarti and the invasion of the pelagic zone by Peridinium cinctum.  相似文献   
78.
Although an understanding of the quantity and quality of sedimentary organic matter (SOM) pools is necessary to design sound environmental management strategies for lacustrine systems, the characterization of organic matter sources and the assessment of their relative contributions to eutrophic and inland lake sediments remain insufficient. In this study, the contribution of potential organic matter sources to sediments in shallow and hypereutrophic lake Taihu, China was assessed on the molecular level using source-specific fatty acid biomarkers. The results indicated that SOM was composed mainly of terrestrial plants with a maximal contribution of 45.3 ± 2.4% to the total organic carbon, which accounted for approximately 66% among the determined organic matter sources. Evidence suggests the terrestrial plants remained in a fresh state in surface sediments: the correlation (R2 = 0.62, p < 0.05) between bacterial and terrestrial plant carbon was strong. On the other hand, aquatic plant and bacterial carbon contributed 5–15% to the total organic carbon, which was followed by the faint contribution (<5% of total organic carbon) of algae-derived organic carbon including cyanobacteria, diatoms, and dinoflagellates. The results provided details of the contributions of SOM sources, illustrating the usefulness of fatty acid biomarkers in discriminating organic matter sources within lake environments. Although organic matter sources of sediments varied in spatial and temporal patterns, the strong correlation between terrestrial plant and total organic carbon (R2 = 0.60, p < 0.05) indicates that terrestrial plants were the dominant source in lake sediments.  相似文献   
79.
若尔盖高原是我国泥炭沼泽湿地的主要分布区、青藏高原的主要甲烷(CH4)排放中心。为了研究湿地微地貌环境对高原湿地CH4排放通量的影响, 2014年5-10月, 采用静态箱和快速温室气体分析仪原位测量若尔盖高原湖滨湿地3种泥炭沼泽5种微地貌环境下的CH4排放通量特征。结果表明: (1)常年性淹水泥炭湿地洼地(P-hollow)和草丘(P-hummock)生长季平均CH4排放通量为68.48和40.32 mg·m-2·h-1, 季节性淹水的泥炭湿地洼地(S-hollow)和草丘(S-hummock)平均CH4排放通量为2.38和0.63 mg·m-2·h-1, 而无淹水平坦地(Lawn)平均CH4排放通量为3.68 mg·m-2·h-1; (2)湿地5种微地貌区CH4排放通量为(23.10 ± 30.28) mg·m-2·h-1 (平均值±标准偏差)), 变异系数为131%。分析显示这5种微地貌区CH4排放通量的平均值与其水位深度平均值存在显著的线性正相关关系(R2 = 0.919, p < 0.01), 表明水位深度是控制湿地微地貌区CH4排放通量空间变化的主要因子; (3) P-hummock、P-hollow和S-hummock的CH4排放通量存在显著的季节变化, Lawn和S-hollow无明显的季节性变化, 但5种微地貌区在夏季或秋季均观测到CH4排放通量峰值, 其影响因子可能与水位深度、土壤温度和凋落物输入密切相关; (4) P-hollow可能时常发生冒泡式CH4排放, 这可能导致过去低估了若尔盖高原湿地的CH4排放量。  相似文献   
80.
Lake Malawi is one of the African Great Lakes and is well known for its fish biodiversity which is the greatest in the world for freshwaters. The lake basin is a valuable resource to the riparian countries. Activities associated with the derivation of the values offered by the lake basin, however, result in the generation of wastes and pollutants that also impact on the lake basin. Such anthropogenic activities within the lake basin place considerable strain on the lake system and may lead to the degradation of the lake basin. Proper application of technology can effectively supplement command-and-control measures and economic instruments for better lake basin management. Currently, no comprehensive framework exists to assess the management of the lake basin. Such a framework is necessary to guide managers and policy-makers in the formulation of management plans and strategies for the sustainable management and utilization of the lake basin. We propose an indicator framework for assessing the technology aspect of Integrated Lake Basin Management (ILBM) in the context of the Lake Malawi Basin. We further demonstrate applicability of the proposed framework through a study conducted in the Malawian side of the basin. We applied a five point Likert-type scale in our indicator assessment. Overall, our results show that the technology aspect of the management of the lake basin is weak to moderate. This threatens the sustainability of the lake especially in the areas of solid waste management, sanitation services, pollution control and protection of wetlands and lagoons which performed from very low to moderate. The major challenges are weak institutional capacity, weak regulation enforcement, and insufficient resources.  相似文献   
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