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1.
秀山岛位于东海舟山渔场海域,岛上有大片的湿地资源分布,其滨海部分与舟山渔场的生物资源特别是渔业生物资源密切联系,具有罕见的海岛特色。海岛的特殊地理位置为秀山岛湿地赋予了独特的生态特征。秀山岛湿地内动植物资源丰富,生物多样性高,共有植物种类300余种,栖息的鸟类共有26个科108种,包括国家一级保护动物东方自鹳(Ixobrychus minutus)。还有国家二级保护动物獐(Hydropotes inermis)等珍贵动物自然栖息。秀山岛湿地包括潮下带湿地(浅海湾)、潮间带湿地(泥滩、芦苇丛)、潮上带湿地(咸水沼泽、半咸水沼泽)、异化湿地(盐田、养殖池、稻田)等几个紧密联系的部分。具有多方面的生态功能。由于对湿地的生态功能重视不够,湿地生态系统破碎化严重。目前在秀山岛湿地已经建立了湿地自然保护区,湿地生态系统得到了较好的发展。 相似文献
2.
鸟类是湿地生态系统重要的一类环境指示生物,研究其群落特征对湿地退化的响应,有助于揭示湿地生态系统结构和功能的变化、探讨对湿地状况进行有效监测和评价的方法。以若尔盖湿地国家级自然保护区花湖、兰州大学高寒草甸与湿地生态系统定位研究站(阿孜站)为研究区域,2018年5、2019年5月采用样线法对区域中4种高原湿地退化梯度,即典型湿地(Ⅰ型)、季节性湿地(Ⅱ型)、中度退化湿地(Ⅲ型)和重度退化湿地(Ⅳ型)的繁殖鸟类群落进行调查研究。研究时段共记录到繁殖鸟类8目14科41种,其中花湖繁殖鸟类39种,阿孜站繁殖鸟类21种。数据分析显示,随着高原湿地退化演替序列,两地的鸟类群落物种数和多样性指数均逐步减小,群落优势度不断增大;Ⅲ型和Ⅳ型群落相似性系数最高,Ⅰ型和Ⅳ型间群落相似性最低,表明鸟类群落随湿地退化发生明显改变,仅与毗邻的退化梯度群落组成相似。研究区域Ⅰ型生境中,水禽类占绝对优势,以红脚鹬( Tringa totanus)为优势种;Ⅱ型中长嘴百灵( Melanocorypha maxima)为群落中优势种;小云雀( Alauda gulgula)和角百灵( Eremophila alpestris)为Ⅲ型群落中的优势种;群落中优势种团为雪雀( Montifringilla spp.)和地山雀( Pseudopodoces humilis)时,标志着湿地已经重度退化(Ⅳ型)。鸟类群落优势种的转变是鸟类营巢环境要求与湿地退化中环境的改变相适应的结果。本研究尝试性的提出如何利用鸟类对高原湿地退化状态进行监测和评价。 相似文献
3.
磷是湿地和农业生态系统中的重要元素之一,其中土壤磷形态的迁移转化广受关注。以哈尼梯田湿地为例,分别在哈尼梯田湿地的水稻生长期、收获期和休闲期,采集湿地不同海拔(梯田区上部、中部和下部)和不同深度的土壤(0-20 cm,20-40 cm,40-60 cm,60-80 cm)进行磷形态分析,研究了哈尼梯田湿地土壤中不同形态磷的时空分布规律和影响因素。结果表明:(1)哈尼梯田湿地土壤中总磷(TP)含量均值为318.74 mg/kg,在水稻收获期含量最高,无机磷(IP)含量均值在水稻休闲期最高(85.95 mg/kg),湿地土壤磷总体呈缺乏状态。(2)受外源磷输入影响,铁铝结合态磷(NaOH-P)占无机磷比重最大,且季节差异性显著( P<0.05);而钙结合态磷(HCl-P)在各季节无显著差异( P>0.05),这与湿地生态环境和地质背景有关。(3)哈尼梯田湿地对磷的迁移有截留作用,表现为各形态磷含量总体呈现在上部梯田湿地较高,并随海拔的降低而降低;不同形态磷含量在20-40 cm土层富集。(4)除HCl-P外,其余形态磷与土壤粒径在不同土层表现为负相关;不同土层TP和有机磷(OP)与pH值呈正相关;土壤总有机碳(TOC)与不同形态磷在收获期呈显著负相关( P<0.05)。研究表明了哈尼梯田湿地立体空间结构和人为活动能影响湿地生态系统中磷的分布与迁移循环,该结论可为梯田湿地的可持续发展提供参考。 相似文献
4.
用碱解离、酸性品红染色法对昆明、澄江、建水、通海、石屏、东川和禄劝等地的15个科32种湿地植物的丛枝菌根状况进行了调查,共发现有11种植物形成丛枝菌根,占34%。从湿地植物根际土壤中分离、鉴定出分属于4个属的丛枝菌根真菌共16种,无梗囊霉属(Acaulospora)和球囊霉属(Glomus)是湿地土壤中的优势类群(94%)。摩西球囊霉(G.mosseae)占孢子总数的88%,是湿地土壤中的优势种。 相似文献
5.
在ELISA对特异性Uu抗体测定的基础上,以90例Uu培养阳性者检测出抗Uu抗体82例(91.1%),其中Ig阳性60例(66,7%),Ig阳性49例(54.4%);与30例Uu多养阴性者比较,抗Uu抗体阳性4例(13.3%),其中IgM阳性1例(3.3%),IgG阳性3例(10.0%),差异显著(P<0.01)。ELISA测定血清抗Uu抗体的特异度为87%,灵敏度96%。该法是临床诊断Uu感染的又一有力手段,且对分析Uu感染的病程有重要参考价值。 相似文献
6.
目的 了解中山市性传播疾病(STD)高危人群中淋球菌(NG)、沙眼衣原体(CT)及解脲支原体(UU)的感染状况,采用聚合酶链反应(PCR)检测1452例STD患者的尿道(宫颈)拭子标本。结果3种病原体的总检出率为25.92,其中NG13.70%、CT31.34%、UU32.71%,混合感染率以CT最高(82.81%),UU次之(75.78%),NG为49.22%。非淋病性尿道炎(NGU)、淋病性尿 相似文献
7.
恢复受损湿地生态功能是国家湿地公园建设中的重要内容,修复措施的选用会对恢复效果产生重要影响。滇池是国内重要候鸟越冬区,受长期围垦以及城市扩张的影响,湖滨区域破坏严重,近年来湿地公园建设为滇池湖滨带恢复带来了契机,但各种恢复措施的效果仍有待明确。2017年冬季以昆明南滇池国家湿地公园及临近湿地为研究区域,设置了人工重建湿地、人工恢复湿地、自然恢复湿地以及自然湖泊湿地4个对照样区,基于冬季水禽多样性进行了湿地恢复效果评价,并从景观生态学角度对结果进行了分析。结果表明:自然湖泊湿地具有最高物种丰富度,其次为自然恢复湿地、人工恢复湿地和人工重建湿地。以Simpson多样性指数评价,自然恢复湿地的水禽多样性最高(0.60±0.03),其次为自然湖泊湿地(0.46±0.04)和人工恢复湿地(0.34±0.04),人工重建湿地水禽多样性最低(0.17±0.03),由此可见自然恢复措施效果优于人工恢复和人工重建。从景观格局上分析,水禽多样性与道路面积( r=-0.735, P<0.01)、景观形状指数( r=-0.461, P<0.01)和景观分离度指数( r=-0.661, P<0.01)负相关,这也表明人为干扰程度、景观形状以及破碎化程度均会对水禽造成重要影响。建议在国家湿地公园规划和建设中,降低非湿地类景观尤其是道路对整体湿地景观的分割作用,提高湿地斑块的连接性和完整性以满足水禽的空间需求,对于湖泊型的湿地公园应加强对湖滨带沼泽生境的营造,以满足涉禽的生存需求,从而增加区域的鸟类多样性。 相似文献
8.
湿地是一种特殊的土地资源和生态环境,具有调节水分循环、维持湿地特有动植物(尤其是作为水禽栖息地)等基本生态功能.天津北大港湿地自然保护区位于天津市东南部,是目前天津市最大的湿地自然保护区.湿地资源丰富,是亚太地区鸟类迁徙路线的一个重要环节,也是白枕鹤、丹顶鹤等濒危鸟类迁徙过程中的一个重要的停歇地.为了研究清楚北大港自然保护区灯下蛾类的种类及其动态规律,筛选出能反映湿地状况和动态的指示性昆虫,为湿地的研究和保护利用服务,于2001年6月12日到10月14日和2002年4月12日到10月30日采用灯诱法系统调查研究了天津北大港湿地自然保护区的蛾类,以微软系统的Excel列表、作图,进行蛾类群落的种-多度曲线作图及群落多样性(H′)、均匀度(J′)、物种丰富度(S)和个体数(N)的时间和空间分布.并利用蛾类群落的种-多度曲线、多样性指数、均匀度与多样性指数的关系等对其作了分析.结果表明,北大港湿地蛾类已知17科105 属 132种,以夜蛾科和草螟科的种类为多.蛾类群落种-多度关系符合生态位优先占领模型.多样性指数与均匀度不相一致(r=0.21),而与物种丰富度一致(r=0.90).这是由于北大港湿地蛾类种-多度关系表现为生态位优先占领假说的缘故.研究认为北大港湿地自然保护区的蛾类种类较少,群落不稳定,即北大港湿地蛾类赖以生存的生态环境不稳定.有待于进一步保护和改善. 相似文献
9.
由于滨海湿地的萎缩和退化对全球鸟类迁徙构成了严重威胁,开展自然湿地或人工构建湿地生态恢复已经成为滨海湿地保护与研究的重要内容。以天津临港二期湿地为例,研究北方滨海人工湿地生物群落快速重建目标及适宜物种清单的确定方法。临港二期湿地2019年共检出浮游植物110种、浮游动物28种,而大型底栖动物仅1种,鱼类未检出,水体生物种类结构单一,难以为迁徙侯鸟提供充足食源。选择与临港二期湿地相同(近)区域、同盐度水平的北大港湿地自然保护区以及临港一期湿地作为备选参照湿地(参考湿地)进行同步生物多样性调查分析,结果表明,北大港水库东区、北大港水库西区、临港一期湿地具有较好的浮游动植物、底栖动物多样性及鱼类资源,可以作为临港二期湿地修复的参照湿地。与参照湿地相比,临港二期湿地具有较好的浮游植物生物多样性,应重点恢复底栖动物与鱼类群落,考虑到后期鱼类恢复后的食物需求,可同步进行浮游动物的增殖放流。以参照湿地生物多样性调查结果与文献资料数据为依据,确定临港二期湿地底栖动物生态恢复目标为:Shannon-Wiener生物多样性指数远期(10年)达到3.00,近期(5年)达到1.58;生物密度远期(10年)恢复至600个/m 2,近期(5年)恢复至300个/m 2;同时确定了临港湿地生物群落快速重建的底栖动物清单(15种)与鱼类清单(14种),并提出了临港二期湿地生态系统恢复的食物网构建路线图。研究结果表明,选择同区域、类似的天然湿地作为参考湿地,通过生物调查与生物多样性比选,确定具体参照湿地,并依据参照湿地生态特征确定待修复湿地的生物群落快速重建目标与适宜物种清单,是合理可行的。 相似文献
10.
从绒毛石耳(Umbilicaria vellea(L)Ach.)提取的水溶性粗多糖,经乙醇分级沉淀和DEAE一纤维素柱层析得到两个组分(UV-2和UV-3),经sepharose6B柱层析和超速离心沉降鉴定为均一组分。通过糖组成分析、高碘酸盐氧化、Smith降解和甲基化分析证明,它们是带有部分乙酰基团的多分枝结构的杂多糖,UV-2的主链是由β(1→3)连接的葡萄糖和甘露糖残基构成,UV-3的主链是由β(1→3)(1→4)连接的葡萄糖残基构成。药理试验结果表明,UV-2具有增强免疫作用,能够明显促进小鼠腹腔巨噬细胞的吞噬功能,提高淋巴细胞的转化率。 相似文献
11.
Summary Wetland fish stocks can usually be sustained as long as the natural flood regime is maintained, but unnatural disruption of the flooding pattern can interfere with fish spawning and feeding. The dynamics of the Phongolo floodplain fish community are determined by periodically changing abiotic factors, especially water level and water temperature, and biotic factors, especially food availability. Water level fluctuations have several important functions and result in pulses of nutrient input and fish abundance. This paper examines the implications of the timing, magnitude and duration of simulated flood releases from the Pongolapoort Dam on the downstream fish and fishery. 相似文献
12.
Due to the fact that the flood data series of small drainage basins is relatively short, available data are often not sufficient for flood risk analysis. This presents the problem of risk analysis using very small data samples. One method that can be applied is to regard the available small samples as fuzzy information and optimize them using information diffusion technology to yield analytical results with greater reliability. In this article a risk analysis method based on information diffusion theory is applied to create a new flood risk analysis model. Application of the model is illustrated taking the Jinhuajiang and Qujiang drainage basins as examples. This is a new attempt at applying information diffusion theory in flood risk analysis. Computations based on this analytical flood risk model can yield an estimated flood damage value that is relatively accurate. This study indicates that the aforementioned model exhibits fairly stable analytical results, even when using a small set of sample data. The results also indicate that information diffusion technology is highly capable of extracting useful information and therefore improves system recognition accuracy. This method can be easily applied and the analytical results produced are easy to understand. Results are accurate enough to act as a guide in disaster situations. 相似文献
13.
The hydrologic regime of the Illinois River has been substantially altered by locks and dams, floodplain levees, water diversion, and development of the watershed over the past 100 years. The natural flood pulse, a fundamental rhythm to which the plants and animals of both the river and its floodplain had adapted, has been disrupted. State, federal, and non‐governmental organizations are currently trying to naturalize the Illinois floodplain‐river system. Little, however, is known about how to recover those elements of the flood pulse essential to the native biota. In this study we propose moist‐soil plants, whose life history is dependent upon flood pulsing, as ecohydrologic indicators of the flood pulse. We explain how moist‐soil plants are supported by the natural flood pulse and present a conceptual framework that links the flooding regimes of the river and the reproductive success of the plants. Successful germination and full growth of moist‐soil plants can be a useful indicator for optimum naturalization of flood regimes. The framework also shows how the interdisciplinary linkages between hydrology, ecology, and spatial analysis assist in predicting, measuring, and comparing consequences of alternative naturalization scenarios. A new ecohydrologic parameter, lowest elevation for successful moist‐soil plant production, is presented. 相似文献
14.
气候变迁,特别是洪水问题给地处三角洲的城市带来了与日俱增的风险。作为应对手段,提出一种整合性的洪水风险管理方法,该方法确保了洪水风险沟通在洪水风险管理战略中的重要地位。洪水的可视化作为洪水风险沟通的一种工具,在改变人们对洪水风险的观念方面有着强大的作用。它可以通过互动的方式,使当地的利益相关者了解洪水的剩余风险和未来风险。其中增强现实技术作为一种可视化手段,它的快速发展与应用为风景园林设计、规划与教育等领域提供了崭新的交互方式。首先,探讨增强现实技术(AR)在洪水风险沟通中的应用现状,并重点关注增强现实技术的2 个关键应用领域:对现场决策的支持和针对高层次设计的可视化与对景观干预的评估。随后,展示一种基于增强现实技术所开发的应用,该款创新性的应用为洪水风险沟通提供了一种轻量化的可视化手段。 相似文献
15.
Although behaviors may remain highly conserved through evolutionary time, the ecological functions they serve can undergo surprising transformations. We used phylogenetic, correlational, and experimental evidence to show how a >150-million year-old behavior, which originally evolved to facilitate migration, has been co-opted for flash flood escape in two distantly related giant water bug species (Hemiptera: Belostomatidae). Using behavioral experiments with simulated rainfall, we showed that species from flash-flooding as well as non-flash-flooding environments are capable of rainfall response behavior (RRB), the ability to use rainfall as a cue to abandon an aquatic habitat. The results suggest that, in addition to allowing individuals to escape flash floods, RRB is the proximate mechanism generating a well-established ecological pattern: The correlation between rainfall and migration to seasonal breeding habitats that has been documented in 13 species throughout the family. Placing RRB in phylogenetic context reveals that for several taxa the behavior is an exaptation (a trait evolved for one function but later co-opted for another) for escaping flash floods. For Lethocerus medius, rainfall response behavior is an addition exaptation because the behavior is used to initiate migration to seasonal rain pools (ancestral function) as well as for flash flood escape (co-opted function). In the distantly related Abedus herberti, rainfall response behavior is a transfer exaptation because it has been co-opted exclusively for flash flood escape and the ancestral function has been lost. These findings emphasize that a phylogenetic framework is needed to fully understand the origins and ecological significance of behaviors. 相似文献
16.
The experimental Sandhill Wetland is the first permanent reclamation of a composite tailings deposit, and annual water quality monitoring is of specific interest for evaluating and predicting long-term reclamation performance. Here, we present water chemistry monitoring data obtained from Sandhill Wetland (years 2009–2019) and compare results to twelve natural reference wetlands and to environmental quality guidelines for Alberta surface waters. By comparing water quality at Sandhill Wetland and natural sites to established guidelines, we can begin to document the natural background water quality of wetlands in the region and examine if guideline exceedances are seen in natural undisturbed environments, or appear only at active reclamation sites. At Sandhill Wetland the dominant ions in near-surface water were bicarbonate, sulfate, chloride, sodium, calcium, and magnesium. Since the first growing season concentrations for these ions have increased annually, causing concurrent increases in electrical conductivity. In year 2019, water chemistry at Sandhill Wetland was most comparable to regional saline fens, systems that exhibit elevated electrical conductivity and high sodicity. Near-surface water at Sandhill Wetland exceeded water quality guidelines for three substances/properties (dissolved chloride, iron, and total alkalinity) in the most recent year of monitoring. The saline fen natural sites also exceeded water quality guidelines for the same chemical substances/properties, suggesting guideline exceedances are a norm for some natural wetland site types in the region. Of note, in each year of monitoring at Sandhill Wetland, dissolved organic compounds evaluated in sub- and near-surface water were below detection limits. 相似文献
17.
洞庭湖是长江流域的第二大湖 ,它吞吐长江 ,接纳四水 ,总库容 1 .8× 1 0 10 m3,年平均迳流量 3.0 1 8× 1 0 11m3,是鄱阳湖的 3倍 ,黄河的 5倍 ,太湖的 1 0倍。洞庭湖区 ,以它不到湖南全省 1 /6的人口和耕地 ,每年生产出占全省总产量 2 0 %以上的粮食和80 %以上的棉花 ,30 %以上的油料和 40 %以上的水产品 ,每年为国家提供 2 .5× 1 0 9kg以上的商品粮 ,1 .5× 1 0 9kg商品棉 ,2 .5× 1 0 8kg商品油和 1 50 0万头商品猪 ,是全国的重点商品粮、棉和水产基地。在地理位置上 ,该区位于长江产业带主轴线和京广、浙赣、枝柳铁路重点开发的二级轴… 相似文献
18.
贵州草海是中国三大高原淡水湖泊之一,其湿地生态系统能给人类提供产品和服务,为社会可持续发展提供基础,由于其价值没有被量化,人们对其重要性缺乏直观认识,导致了湿地的不合理开发及利用。根据草海湿地的特征,运用市场价值法、影子工程法、问卷调查法等定量评估了2010年草海湿地生态系统最终服务价值,包括供给服务、调节服务和文化服务。结果表明,草海湿地生态系统服务总价值为4.39×108元,其中供给服务价值为0.74×108元,调节服务价值为1.14×108元,文化服务价值为2.51×108元;所计算的10项服务按其价值大小排序为:休闲娱乐生物多样性与景观资源保护水资源供给调蓄洪水气候调节补给地下水大气组分调节原材料生产水质净化食物生产;单位面积服务价值为16.40×104元/hm2,是2010年贵州省威宁县单位面积GDP产值的16.91倍。从研究结果来看,草海湿地生态系统服务价值较大,为草海湿地的管理及保护提供了一定参考依据。 相似文献
19.
Summary Large overbank flood events play an important role in maintaining large‐scale ecological processes and connectivity along and across the floodplains and between the rivers and their floodplains in the southern Murray‐Darling Basin. However, the regulation of rivers means that extensive overbank flooding can only occur in the rare circumstance of extreme flood events. Recent environmental water allocations have focussed on the largest floodplain blocks (‘icon’ sites) and a small set of specific values (e.g. colonial nesting waterbirds), as well as on trialling fine‐scale manipulation of infrastructure (e.g. pumping) to water relatively small areas. There has been no comprehensive systematic assessment of the entire floodplain and its wider set of flood‐dependent natural assets (such as ecosystems and species; herein referred to as ‘natural values’) to maximise the effectiveness of environmental water use and to catalogue values likely to be lost. This paper describes an assessment of some 220 000 ha found to support flood‐dependent natural values in Victoria. We mapped the geographic distribution and estimated components of the flooding requirements (natural flooding frequency, and maximum period without flooding and minimum duration of each flooding event before significant deterioration) for each natural value. Using an example of one stretch of the River Murray, we show how the resultant spatial data can be used with floodplain inundation modelling to compare the outcomes of real or planned environmental watering events; potentially providing tools for management agencies to conserve a wider range of floodplain values than is currently the case. That is, water managers and the public can see what ecosystems and threatened species are intended to be maintained by environmental watering and what values are intended to be abandoned across the whole floodplain, rather than just seeing the small subset of values and ‘icon’ sites that are intended to be maintained. Examples are provided to illustrate how information about the location, water requirements and extent covered by potential floods for specific values can be used to build adaptive watering strategies for areas as large as the whole floodplain. 相似文献
20.
Human activities are affecting the environment at continental and global scales. An example of this is the Mississippi basin where there has been a large scale loss of wetlands and water quality deterioration over the past century. Wetland and riparian ecosystems have been isolated from rivers and streams. Wetland loss is due both to drainage and reclamation, mainly for agriculture, and to isolation from the river by levees, as in the Mississippi delta. There has been a decline in water quality due to increasing use of fertilizers, enhanced drainage and the loss of wetlands for cleaning water. Water quality has deteriorated throughout the basin and high nitrogen in the Mississippi river is causing a large area of hypoxia in the Gulf of Mexico adjacent to the Mississippi delta. Since the causes of these problems are distributed over the basin, the solution also needs to be distributed over the basin. Ecotechnology and ecological engineering offer the only ecologically sound and cost-effective method of solving these problems. Wetlands to promote nitrogen removal, mainly through denitrification but also through burial and plant uptake, offer a sound ecotechnological solution. At the level of the Mississippi basin, changes in farming practices and use of wetlands for nitrogen assimilation can reduce nitrogen levels in the River. There are additional benefits of restoration of wetland and riverine ecosystems, flood control, reduction in public health threats, and enhanced wildlife and fisheries. At the local drainage basin level, the use of river diversions in the Mississippi delta can address both problems of coastal land loss and water quality deterioration. Nitrate levels in diverted river water are rapidly reduced as water flows through coastal watersheds. At the local level, wetlands are being used to treat municipal wastewater. This is a cost-effective method, which results in improved water quality, enhanced wetland productivity and increased accretion. The problems in the Mississippi basin serves as an example for other watersheds in the Gulf of Mexico. This is especially important in Mexico, where there is a strong need for economical solutions to ecological problems. The Usumacinta delta-Laguna de Terminos regional ecosystem is an example where ecotechnological approaches offer realistic solutions to environmental problems. 相似文献
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