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Li-li Ouyang Yang-dong Pan Cheng-min Huang Ya Tang Jie Du Wei-yang Xiao 《山地科学学报》2016,13(9):1632-1644
Jiuzhaigou, characterized by its magnificent waterscapes and subalpine karstic features, is both a World Heritage Site and a World Biosphere Reserve in southwestern China. In recent years, this unique ecosystem has shown signs of stress due to increasing tourism activities within the reserve. The various routine methods, which monitor physical and chemical properties, do not fully reflect water quality in the subalpine and alpine lakes, while the indicators using aquatic organisms to evaluate the water quality or status of the subalpine lakes are poorly reported. Thus, in this study, benthic diatoms from multiple habitats in Jiuzhaigou were sampled and assessed for water quality monitoring. Canonical Correspondence Analysis (CCA) showed that the canonical coefficients for elevation, water temperature and total nitrogen on the first Canonical Correspondence Analysis axis were -0.84, 0.78 and -0.53, respectively, environmental variables associated with the distribution patterns of benthic diatoms. The dominance of diatom taxa indicative of nutrient enrichment indicates a clear trend toward eutrophication in the Pearl Shoal and Colorful Lake, two of the sites mostly visited by tourists. It was observed that the effect of the type of substratum on diatom community composition is not significant in subalpine lakes. The most dominant species in Jiuzhaigou lakes are the genera Achnanthes, Fragilaria, Cymbella, Cocconeis, Diatoma and Denticula. In combination with dominant and sensitive species in the benthic diatom communities, CCA and CA methods can be used to evaluate the impact of human activities on subalpine karstic lakes. The dominance of diatom taxa is indicative of nutrient enrichment and the results of CCA and CA indicate a clear trend toward eutrophication in the Pearl Shoal and Colorful Lake, two of the sites mostly visited by tourists. 相似文献
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野鸭湖湿地自然保护区是北京最大的湿地自然保护区,也是唯一的湿地鸟类自然保护区,因此,选择野鸭湖研究城市湿地景观格局演变特征具有典型意义。以野鸭湖自然保护区为研究对象,分析了1999年、2004年、2009年和2014年4个时期野鸭湖湿地系统景观格局演变过程,并根据景观指数分析其动态变化趋势。研究结果表明:①野鸭湖湿地面积在1999~2004年间逐渐减少,之后逐年恢复,至2014年湿地面积总数已恢复到1999年的水平,但水体的面积仍缩减一半,主要恢复的是草甸湿地和疏林湿地。②野鸭湖湿地景观格局的变化特征主要表现为:景观破碎度增加,景观形状更加复杂,景观多样性和异质性增加而优势度降低。③野鸭湖湿地斑块类型呈现如下特征:耕地连片分布,耕地开垦力度减缓;草甸湿地成片增长且优势度逐渐明显,形状复杂;水体分布聚集,2014年出现恢复现象;疏林湿地面积不断增长,呈现破碎化现象;建筑用地面积也略微增长,但分布分散;滩涂湿地面积最小,形状简单。 相似文献
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近30年天津滨海新区湿地景观格局遥感监测分析 总被引：6，自引：0，他引：6
在GIS和FRAGSTATS软件支持下,结合景观格局数量分析方法,利用1979-2008年间共6期TM遥感影像与非遥感数据,对天津滨海新区近30年的湿地景观空间格局进行了动态分析。结果表明,滨海新区湿地(以人工湿地为主),1979-2004年滨海新区湿地总面积变化不大,但各类型间转换较大,主要是自然湿地转变为人工湿地,沼泽湿地几近消失。2006-2008年,由于城市建设大量滨海滩涂湿地被围填占用,到2009年5月自然海岸线的90%以上被占用。景观破碎度增加,湿地斑块数量从137个增加到704个,同时造成平均斑块面积下降。驱动力分析表明,降雨量减少的同时,年平均气温上升是主要的自然驱动因素。和自然因素相比,人类干扰为主要人文驱动因素,表现在水产养殖为主的农业经济活动、城市建设用地占用和围海造地等方面。目前,滨海新区几乎没有自然湿地生态系统,破碎化和人工化是该区域湿地的主要特征。 相似文献
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《中国地理科学(英文版)》2019,(3)
Deyeuxia angustifolia wetlands were widely distributed in the Sanjiang Plain in Northeast China. Due to strong demand for food production, large-area wetlands were reclaimed to farmlands, which threatened regional ecological security greatly. Since the 21 th century, returning farmlands to wetlands was widely adopted for natural restoration in the Sangjiang Plain. As the first reflection of wetland restoration, vegetation succession of restored D. angustifolia wetlands should be fully assessed. In this study, vegetation investigation was carried out in three restored D. angustifolia wetlands with 5, 8 and 12 yr restoration, respectively. Meanwhile, a natural D. angustifolia wetland was selected as reference wetland. Results showed that community composition changed greatly and there was visible community succession. Community dominant species changed from composite to gramineae as restoration time increasing.At first, weeds community appeared in the restored wetlands, especially the xerophytes developed to the pioneer species rapidly. And then, mesophytes and wetland species became the dominant species in the restored wetlands. Finally, wetland species, especially D. angustifolia, occupied the dominant position of restored community. Shannon-wiener index(H) and Simpson index(D) both decreased to close to natural D. angustifolia wetlands. Compared with natural D. angustifolia wetland, species composition and diversity in restored wetlands were more complex and higher. As restoration time increasing, there were not significant differences between community characteristics of restored wetlands and natural wetland. All these suggested that vegetation in reclaimed D. angustifolia wetland could be restored naturally, but its restored period is 10 yr at least. From another angle, it is important to protect current natural wetlands. 相似文献
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塔里木河下游地区是我国西部干旱区生态环境问题比较突出的区域。本文主要从地表水(湖泊、河流和湿地)、地下水、地表植被覆盖的角度,基于多源遥感和长时间序列数据,监测和分析生态输水前后区域环境变化和生态响应。首先,采用基于知识迁移的专题图斑更新技术,实现了1990、1995、2000、2005、2010和2015年区域湿地遥感制图和植被覆盖度等生态因子指标提取;然后,以2000年为基准（生态输水起始年）,结合地下水位观测数据,对比分析了人工生态输水前后区域生态环境动态变化过程。结果显示：① 生态输水前（1990-2000年）,塔河下游的生态环境持续恶化,流域范围内一半以上的沼泽湿地消失、河道干涸,地下水位下降,区域植被覆盖大幅度下降;② 生态输水后（2000-2017年）,区域生态环境明显好转,改变了下游河道长期断流状态,区域地下水位明显抬升,地表水域（湖泊和沼泽）面积呈现“V”型逆转增加,区域植被覆盖区和覆盖度均呈现显著增加趋势,曾经一度干涸的塔河尾闾台特玛湖水域面积2017年8月达到147.87 km2。以上研究结果综合表明人工生态输水工程对塔河下游生态环境拯救和治理发挥了重要作用,遏制了生态输水前塔河下游生态环境继续恶化局面,流域生态环境正在逐步恢复。 相似文献
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Diatoms are widely used to study past and present changes in the marine environment. Unimodal models are appropriate for exploring the relationship between environmental properties in Chinese inshore waters and fossil diatom species derived from modem surface sediments. The best-fit relationships between two multivariate datasets （diatom species and environmental variables） were identified using canonical correspondence analysis （CCA）, which is a constrained ordination technique. The absolute abundance of diatoms in the Chinese inshore waters ranged from 500 to 48 000 valves/g, and the average absolute abundance of all the 29 sites was l l 300 valves/g. 153 species and varieties of diatoms belonging to 42 genera in all were identified in the Chinese inshore waters. There were 28 dominant diatom species in all. According to the absolute abundance of the dominant species and the spatial distribution of the currents from the Chinese inshore waters, 12 diatom assemblages were distinguished from north to south, which reflected the different oceanographic conditions at the regional scale. Of the eight environmental variables considered, the most important environmental variable is winter sea surface salinity （WSS）, which was also the only environmental variable with statistical significance. Therefore, it may be used to establish a transfer functions for the Chinese inshore waters in future paleoclimate studies. 相似文献
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The individual or combined ef fect of water temperature and silicate on seasonal shift of dominant diatom species in a drinking water reservoir in China was studied in this paper. These ef fects were analyzed based on the field investigation of temporal dynamics in species composition and abundance of phytoplankton and environmental factors from September 2015 to August 2016. We firstly found that six dominant diatom species( Fragilaria nanana, Achnanthidium catenatum, Aulacoseira ambigua, Ulnaria ulna, Cyclotella meneghiniana and Asterionella formosa(Class Bacillariophyceae)), which accounted for98.7% of the total abundance of diatoms and 46.8% of the total abundance of phytoplankton, showed an obvious seasonal succession. Then significant driving factors for seasonal shift of the dominant diatom species were selected by Redundancy Analysis. The result showed that water temperature and silicate were the main environmental factors af fecting the growth of diatoms on temporal scales. Next, the regressions of water temperature and silicate and dominant diatom abundance were fitted in Generalized Additive Model separately, and the smoothers of water temperature and diatom species suggested that the dominant diatom species adapted to dif ferent optimum temperature ranges, which corresponded with the growth of seasonal changes. A positive linear correlation between silicate and diatom abundance was generated by Generalized Additive Model. Finally, the ordinal controls of water temperature and silicate on the growth of diatoms were analyzed on temporal scales specifically. We suggested that water temperature and silicate controlling the growth of diatoms in order. Diatoms grow well only when the two controlling factors simultaneously satisfy the growth conditions; as limiting factors, the two factors played their respective limiting roles in turn on temporal scales. 相似文献
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Nan Li Xue Tian Yu Li Hongchen Fu Xueying Jia Guangze Jin Ming Jiang 《中国地理科学(英文版)》2018,28(6):1027-1037
To investigate the spatio-temporal and compositional variation of selected water quality parameters and understand the purifying effects of wetland in Fujin National Wetland Park(FNWP), China, the trophic level index(TLI), paired samples t-test and correlation analysis were used for the statistical analysis of a set of 10 water quality parameters. The analyses were based on water samples collected from 22 stations in FNWP between 2014 and 2016. Results initially reveal that total nitrogen(TN) concentrations are above class V levels(2 mg/L), total phosphorus(TP) concentrations are below class Ⅲ levels(0.2 mg/L), and that all other parameters fall within standard ranges. Highest values for TN, pH, and Chlorophyll-a were recorded in 2016, while the levels of chemical oxygen demand(COD_(Mn)) and biochemical oxygen demand(BOD5) were lowest during this year. Similarly, TN values were highest between 2014 and 2016 while dissolved oxygen(DO) concentrations were lowest in the summer and TP concentrations were highest in the autumn. Significant variations were also found in Secchi depth(SD), TN, CODMn(P 0.01), TP, and DO levels(P 0.05) between the inlet and outlet of the park. High-to-low levels of TN, TP, and TDS were found in cattails, reeds, and open water(the opposite trend was seen in SD levels). Tested wetland water had a light eutrophication status in most cases and TN and TP removal rates were between 7.54%–84.36% and 37.50%–70.83%, respectively. Data also show no significant annual changes in water quality within this wetland, although obvious affects from surrounding agricultural drainage were nevertheless recorded. Results reveal a high major nutrient removal efficiency(N and P). The upper limits of these phenomena should be addressed in future research alongside a more efficient and scientific agricultural layout for the regions in and around the FNWP. 相似文献
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Shuangtaizi estuarine wetland along the Bohai Sea coast, the biggest bulrush wetland in the world, has been listed in ‘The
Record of Important International Wetland Conservation District’. Taking the year of 2 000 as an example, the minimum, the
most suitable and the maximum ecological water requirement of Shuangtaizi estuarine wetland are calculated in this paper based
on both ecological theory and Geological Information System technology. In addition, the remote sensing technique is adopted
in the data acquisition process. Moreover, the total water requirement and the unit area water requirement for different wetland
types are obtained. The result is very important for water resources planning, ecological conservation and regional agriculture
structure adjustment in Shuangtaizi. Meanwhile, this study can serve as a useful example for calculating the ecological water
requirement in other similar estuarine wetlands. 相似文献
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LI Jie HU Jin-ming DENG Wei HUANG Sheng-li JIA Hai-feng ZHU Chun-ling LUO Huai-xiu 《山地科学学报》2013,10(4):553-563
Mountains and plateaus in Southwest China contain many subalpine and alpine wetlands, with significant hydroecological functions. But ungauged or poorly gauged conditions limit the study and understanding of hydrological regimes of these wetland types. This study selects an ungauged subalpine wetland-Napahai in Northwest Yunnan, China-as a case for developing a practical approach to revealing its storage-area relationship of open water. A Trimble R8 GNSS (Global Navigation Satellites Systems) RTK (Real-time Kinematic system) and sonar fathometer were used to survey fine-resolution elevation data and generate a digital elevation model of the Napahai Wetland. Forty-four Landsat images from 1987 to 2011 were collected, and the Normalized Difference Water Index was used to classify open water features in the area. The area of open water in Napahai was calculated for each phase. With these data and a developed conceptual model, the storage of open water for each phase was estimated using ArcGIS tools. Both storage and area of open water showed significant intra-annual and inter-annual variations. In the rainy season, the monthly change of average storage of open water in Napahai showed about 1-2 months lag behind mean monthly rainfall. The storage-area relationship of open water was well fit by a power function equation (R 2 ≈0.91, n=44). This study indicates that if detailedelevations are available for similarly ungauged subalpine wetlands in Southwest China, researchers can use this practical approach to estimate multi- temporal areas and storages and reveal the storage-area relationship of open water in the wetlands. The study provided valuable information of this case wetland for optimizing its hydro-ecological managements and a new method to wetland researchers and managers for the hydrological study of similarly ungauged wetland complex. 相似文献
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Assessment on the commonweal values of wetlands 总被引：2，自引：1，他引：1
1THECOMPOSITIONOFWETLANDS'COMMONWEALVALUESThematterflow,energyflowandinformationflowgeneratedfromnaturalcapitalofwetlandsformecosystemcommonwealvalues.Theflowsaswellasartificialcapitalandlaborcapitalcommonlygeneratehumanitywelfare(COSTANZAetal.,1997).Generallyspeaking,thevaluesofwetlandsmaybedividedintothreetypes:directproductionvalues,valuesbroughtwithbiologicalfunctionsofwetlandsecosystem,andattributivevaluesaspartofsocialmakeup(BARBIER,1997).Thesevaluescannotallbeembod… 相似文献
13.
Shuangtaizi estuarine wetland along the Bohai Sea coast,the biggest bulrush wetland in the world,has been listed in ‘The Record of Important International Wetland Conservation District’. Taking the year of 2 000 as an example,the minimum,the most suitable and the maximum ecological water requirement of Shuangtaizi estuarine wetland are calculated in this paper based on both ecological theory and Geological Information System technology. In addition,the remote sensing technique is adopted in the data acquisi... 相似文献
14.
河道湿地是流域生态系统中,位于水陆交错地带,关联陆地生态系统和水生生态系统的桥梁和纽带,对蓄水滞洪、净化水质和水土保持,以下维持生物多样性和生态平衡起重要的作用。本文采用1986、1996、2000、2006和2015年5期Landsat遥感影像数据对刘家峡以下黄河上游湿地进行湿地解译提取,并利用空间统计分析法、转移矩阵法和质心位置变化法对刘家峡以下黄河上游河段河道湿地演变规律以及驱动力因素进行研究。结果表明,1986-2015年,黄河上游河道湿地面积从17.3万hm2逐渐减少到12.2万hm2,减少了29.0%。研究区土地利用类型的转移主要发生在河流、裸滩、草本湿地与耕地的相互转化上。过去30年嫩滩湿地的变化幅度远大于老滩湿地,嫩滩湿地面积从1986年的15.46万hm2减少到2015年的10.41万hm2,减少了32.7%,嫩滩湿地演变规律为天生湿地型之间的相互演变,即河流-裸滩-沼泽湿地。而老滩湿地面积基本处在稳定状态,面积范围在1.84~2.28万hm2之间,具有天然湿地-人工湿地与天然湿地-农业用地的演变规律特征。水渠湿地、坑塘湿地和森林湿地质心位置变化较为突出,由单一类型动态度分析可知,研究区自然湿地萎缩、城镇化加速、河流水面面积减少加快。以上分析结果与研究区气温、水利水电工程、灌溉用水、凌汛期冰情以及城镇化程度均有关,与降雨量无明确关系。 相似文献
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Based on multi-source data,this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve,Beijing,China.The ecological services of wetland included gas regulation,water quality im-provement,biodiversity maintenance,erosion control,water supply,recreational opportunity,raw material supply and existence value.Multiple conventional evaluation methods were used to calculate the value of eight wetland services.The results showed that significant values came from biodiversity maintenance and recreational opportunity.The main reasons were as follows.Firstly,Yeyahu Wetland Nature Reserve was the habitat for migrant birds,and government had payed more efforts to protect precious birds.Secondly,the population is large in Beijing.People enjoyed going outside and enjoyed the natural and artificial wetland scenes.At the same time,most people were prepared to pay for wetland conservation.The decline of vegetation cover made the economic value of erosion control the lowest.While the shrink of water resource and the deteriorative water quality caused the economic value of water supply lower.The evaluation results could help decision-makers understand the present status of the Yeyahu Wetland Nature Reserve and provide a scientific basis for strategic decision. 相似文献
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Wetland Is an important landscape existing almost DEFINITIONS OF WETLANDall over the world．In China，wetlands are distributedeverywhe。加mfrlgld－tern。。。ie zone to tropical zone，XU QI et al．dehned wetland as the soil which isfrom lmoral！o Inland from paln to pforeau and moisten by under－ground water or Is permanently ormountains．＞ome ot the wetlands share the sam。char－temno。rllv soak。d by ground。ater（XU，1995）．Thisacterlstlcs of other countries，and some are un… 相似文献
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Xinxiang Cao 《中国地理科学(英文版)》2008,18(2):146-154
It is very significant for urban development and urban wetland protection and utilization to probe into the process and reasons of urban wetland landscape dynamics. Taking the information of remote sensing and detailed land survey data as the basic information sources, with the help of RS and GIS, according to the principles and methods of landscape ecology, this paper analyzed wetland landscape pattern dynamics and its reasons in Kaifeng City, Henan Province of China, from 1987 to 2002. The results show that the total wetland area in Kaifeng City firstly reduced by 20.1% from 1987 to 1990 and then increased from 1990 to 2002, with an average annual growth rate of 3.3%. At the same time, landscape fragment degree and landscape dominance degree increased, respectively from 0.64 to 0.72 and from 0.3754 to 0.5563, but mean patch area, maximum patch area, patch fractal dimension reduced. As far as single landscape element concerned, fi＇om 1987 to 2002, patch area, patch number, patch density, patch shape and patch location changed in varying degrees in all wetland types in Kaifeng City, among which rice field changed most and others relatively less. In the recent 20 years, rice fields, lake wetlands, puddles and ponds had a higher stability, but river and bottomland wetlands were mostly transformed to land use types. The change of wetland landscape pattern was the result of the combined action of the Huanghe （Yellow） River, urban expansion, wide cultivation of rice, and rapid development of fishery. Among them human activities were the main driving factors for wetland landscape changes. 相似文献
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莱州湾南岸滨海湿地作为环渤海滨海湿地的一部分,具有海洋与河口交互性、海陆过渡性和生态脆弱性等特点,湿地面积广阔、资源丰富,是东北亚环西太平洋鸟类迁徙的重要“中转站”及越冬、栖息和繁殖地。湿地总面积为1150．079km^2,湿地维管束植物区系包括维管束植物53科144属217种。近年来,在对滨海湿地的开发中,虾池、盐田等人工湿地面积不断扩大,造成自然湿地面积减小、植被退化、地貌和水文条件改变、生物多样性下降,改变了原始的滨海湿地自然景观,破坏了珍稀鸟类的生存环境。 相似文献
19.
研究了人工湿地循环处理哈氏仿对虾(Parapenaeopsis hardwickii)高盐度(21.1-23.3)养殖废水的净化效果。人工湿地对高盐度养殖废水中各水质指标去除率为:总氨氮66.7%,亚硝酸盐80.0%,化学需氧量12.5%,浊度69.1%,硝酸盐-12.1%,总氮3.5%,总磷0.0%。养殖池水质状况良好。在试验负载范围内,湿地对总氨氮、亚硝酸盐、浊度的去除量随进水污染负载量的增加而增加。研究表明:人工湿地能持续有效降低哈氏仿对虾养殖废水中的主要水质因子浓度。 相似文献
20.
近40年来白洋淀湿地土地覆被变化分析 总被引：4，自引：0，他引：4
白洋淀是华北平原上现存最大的天然湖泊,是典型的内陆湿地。最近40年,白洋淀湿地出现了水面萎缩、生态功能急剧退化、生物多样性减小和水体污染严重等生态环境问题。本文利用1964年CORONA侦察卫星影像、1974年和1983年Landsat MSS影像和2002年ETM+影像,对白洋淀湿地的土地覆被变化及其驱动力做了详细分析。结果表明,湿地面积呈减少趋势:1964年为407.3km2,2002年缩减到274.63km2。湿地水面起伏变化大,1964年水面较宽,为346.75km2;到1974的10年间,减少到94.65km2,1983年和2002年水面继续变窄,水面面积分别为67.27km2和46.86km2。引起湿地土地覆被变化的原因包括降雨量的减少、蒸发量的增大、城市发展用水增大、不合理土地利用开发和上游水库、引水工程修筑等。 相似文献