62 resultados para Zoige wetland

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若尔盖高原湿地位于青藏高原东北部地区,平均海拔3,400-3,600m,是长江和黄河的自然分水区,区内发育了大面积的草本沼泽以及高寒沼泽化草甸、高寒湖泊。由于它所处的位置海拔高、气候波动较大,并处于我国三大自然区的交错过渡带,因而被认为是我国最为典型的脆弱湿地生态系统之一。由于地处偏远、自然环境条件恶劣等多方面的原因,针对若尔盖湿地的科学研究资料一直以来还非常缺乏。本文对国内外近年来在湿地生态系统甲烷排放过程、研究方法,以及关于湿地生态系统甲烷排放的影响因素进行了综述,并采用静态箱-气相色谱法,从湿地环境格局、湿地甲烷排放等方面,对若尔盖高原典型高寒湖泊湖滨不同类型湿地甲烷排放特征进行了研究,并进一步探讨了影响若尔盖高原高寒湖泊湖滨带甲烷排放的因素。得到如下结果:1.若尔盖高原花湖湖滨湿地在植物生长季(6 至8 月),甲烷排放平均速率为0.315 mg·m-2·h-1;不同月份间甲烷排放速率存在差异,分别为:-0.054、0.471、0.493 mg·m-2·h-1。不同类型湿地甲烷排放速率亦表现出差异,两栖蓼(Polygonum amphibium)湿地、滩涂和藏嵩草(Kobresia tibetica)草甸甲烷排放速率分别为:0.464、0.477、0.005mg·m-2·h-1。2.若尔盖高原花湖湖滨湿地甲烷排放速率与土壤10cm 温度显著相关。土壤温度是影响若尔盖高原花湖湖滨不同类型湿地甲烷排放的重要因素之一。随着土壤温度的升高,土壤微生物活性增强,使土壤中的氧消耗加快,氧化还原电位下降,有利于产甲烷菌的生长,从而增加土壤的甲烷产生量。3.地表水位与若尔盖高原花湖湖滨湿地甲烷排放速率相关性不显著。地表水覆盖,使得湿地土壤缺氧状况得到加强,增强了土壤中产甲烷菌的活性,促进甲烷形成,再通过植物、气泡或扩散的形式释放出土壤。但水层的加深,也使土壤中已产生的甲烷在通过气泡或扩散形式穿越水层时,被氧化的量增加,从而减少了甲烷向大气中的排放。4.植被高度以及植被地上生物量与若尔盖高原花湖湖滨带甲烷排放速率的相关性不显著。植物主要通过凋落物以及根系分泌物的输入为产甲烷菌提供基质,并作为土壤与大气之间的甲烷气体交换的传输途径;与其他环境因素共同影响湿地生态系统甲烷排放。The Zoige wetland on the eastern fringe of Qinghai-Tibetan Plateau, with averagealtitude between 3,400 and 3,600m, is the watershed of Yangtze River and YellowRiver. There are large area of peatland, subalpine meadow and lakes in this region.Due to its high elevation, transitional topology and high fluctuation of climate, theZoige wetlands represent one of the most fragile wetland ecosystems in China. And asa result of remote location and harsh environment conditions, the researches on theZoige wetland are relatively rare, especially the researches on the methane emissionfrom littoral zone of alpine lakes. Variations of methane emission rates as measuredby the method of static chamber – gas chromatography (GC) were detected fromlittoral zone of alpine lake on the Zoige Plateau. Relationships between methaneemission rates and environmental factors were analyzed. It is concluded that:1.The average methane emission rate in the littoral zone of Huahu Lake, ZoigePlateau is 0.315 mg·m-2·h-1, with evident spatial and temporal variations. The littoralzone has different methane effluxes with -0.054, 0.471, and 0.493 mg·CH4·m-2·h-1in June, July and August respectively. Different types of wetland have differentmethane emission rates, with value of 0.464, 0.477, and 0.005 mg·CH4·m-2·h-1 forPolygonum amphibium wetland ( PA ), Shoal ( S ) and Kobresi tibetica meadow ( KT ), respectively.2. The soil temperature at 10cm is significantly correlated with the methane effluxesin littoral zone of Huahu Lake, Zoige Plateau, and which is one of the most important factors influencing the methane emission from this region. The activities of soilmicroorganisms rise under higher soil temperature and increases oxygen consumptionand decreases Eh, which is in favor of the methanogensis, and enhances theproduction of methane in soil.3. The correlation between the standing water and methane effluxes from littoralzone of Huahu Lake is not significant. Because of the standing water, the anaerobicconditions of wetland soil have been enhanced, and are favor to the decomposition oforganic matter. And the anaerobic conditions strengthen the methanogensis’ activities,thus the methane production, which release to the atmosphere by diffusion, ebullitionand aerenchymal plants. With the water level’s increase, more methane produced insoil which is transferred by ebullitions or diffusion are oxidated, thus reduce themethane release to the atmosphere.4. The height and aboveground biomass of vegetation are not significant related tothe methane effluxes from littoral zone of Huahu Lake, Zoige Plateau. The vegetationprovides substrates for methanogensis by litter and root exudates; act as thetransportation way of methane between soil and atmosphere; influence the methaneemission of wetland ecosystems with other environment factors.

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揭示水体中繁殖的两栖动物在异质性景观中的空间扩散特点,探讨景观面积丧失和破碎化对于两栖动物的影响,为两栖动物的保护提供理论依据。本文以四川西北部若尔盖湿地自然保护区的高原林蛙(Rana kukunoris)为研究对象,通过运用地理信息系统及建立景观模型等方法,在分析若尔盖湿地自然保护区范围内现有景观格局的基础上,建立了高原林蛙的景观扩散模型,并模拟了“沼泽→草甸”的湿地逆演化过程下高原林蛙的空间分布与景观连接的变化特点。主要结果是: 1.若尔盖湿地自然保护区呈典型的沼泽—草甸式斑块—基质景观格局。草甸面积占整个景观面积的79.42%,景观蔓延度指数(CONTAG)为79.00远离最小值0而更趋向于最大值100,面积和景观蔓延度指数表明草甸是整个景观中面积占绝对优势且景观连接好的类型,构成了景观的基质,对景观的动态格局演变起主导作用。沼泽面积仅占整个景观面积的18.08%,但却是整个景观中斑块数目最多的单元,占所有斑块数的82.9%。因此沼泽斑块与草甸基质之间的动态结构对高原林蛙的扩散起着决定性的作用。 2.空间扩散模型表明,其它类型的景观不但扩展了高原林蛙的活动范围,而且也为高原林蛙在不同沼泽斑块间的连接提供了通道。高原林蛙的空间扩散区域使得彼此间成斑块化隔离状分布的沼泽形成了潜在景观功能连接,促进了不同斑块间物种的交流。小型沼泽作为垫脚石(stepping-stone),使得整个景观中的相隔距离较远的大型斑块联结为一个功能整体,促进了高原林蛙在整个景观中的相互动态联系。 3.模拟“沼泽→草甸”的湿地逆演化过程表明,大量小型沼泽湿地的消失将会 对在沼泽中繁殖并扩散到其它景观类型中去的高原林蛙造成潜在影响。逆演化过程不仅使沼泽斑块的分布范围,沼泽源斑块的面积和空间扩散面积减少,而且对景观连接也有很大影响。小型沼泽的消失,将使得景观斑块的功能连接变小,使得依靠小型沼泽作为跳板的动物在沼泽斑块之间的移动将变得更加困难。 本文是对生境丧失与破碎化影响下两栖动物的行为反应的一种尝试。影响模型的因素很多,包括动物对各种类型景观的偏好程度,地理数据的精度,及模型的可靠程度都是制约模型准确度的因素。 The spatial diffusion of water—breeding amphibian through heterogeneous landscape and the effects of landscape losing and fragmentation to amphibian were the core theory of the landscape ecology of amphibian. Geographical information system (GIS) and landscape model were used to model the diffused area of Rana kukunoris in Zoige Wetland Natural Reserve. Model was also used to analysis the spatial distribution variation of R. kukunoris and the change of landscape connectivity when simulated the retrogressive succession of landscape. The main results are below: 1. There was peatland—meadow pattern which was typical patch—matrix landscape pattern in Zoige Natural Reserve. The meadow area occupied 79.42% of the entire landscape area, contagion index (CONTAG) was 79.00 which was far away the minimum value (0) but tend to the maximum value (100). Both of these showed that meadow was the largest part and the most continue units. It was shown that meadow was matrix of the landscape, which evolved the leading role to the landscape dynamic pattern. Though their area only occupies 18.08% of entire landscape area, peatlands were according to 82.9% of the total patches. Dynamic of the pattern between peatlands and meadows decided the spatial diffusion of R. kukunoris. 2.The model indicated that the other types of landscape not only expanded diffusion of R. kukunoris, but also have provided the potential channels for frog's connections among different peatlands. The spatial diffusion zone of R. kukunoris forced isolated patch peatlands to be potential landscape functional connectivity. The small peatlands, as stepping-stone, made the large peatlands connect as a functional one and promoted the integrated and dynamic connectivity of R. kukunoris in the whole landscape. 3. The simulation of “peatlands→meadows”retrogressive succession process indicated that the decrease of small peatlands will have potential effect to R. kukunoris because they must bred in peatlands and diffuse to other type of the landscape. Retrogressive succession process not only made the decrease of distribution of peatlands, patches number of peatlands and diffused area of R. kukunoris, but also reduced the connectivity among source patches. As stepping-stone, the disappearance of small peatlands will made the migration of R. kukunoris among patches more difficult. The model was an experiment of the amphibian behavior reaction to habitat losing and fragmentation. There were many factors that could influence the accuracy of model, such as the preference of animals to each type of landscape, the geographical data precision, reliable degree of model.

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从空间、时间、食物3个方面研究了若尔盖湿地3种两栖类的种间竞争,运用生态位理论探讨了3种两栖类利用环境资源的能力以及它们之间的共存模式,研究了3种两栖类年周期食性,并考察了畜牧业对3种两栖类食性及食物竞争格局的影响;此外,还通过实验室研究对2种两栖类幼体的种间竞争策略进行了考察。主要结果如下: 1、两栖类的空间资源利用状况:在3种两栖类成体生态位宽度的比较中,岷山蟾蜍(Bufo minshanicus)成体在牧场性质(0.41)、牛粪数量(0.42)、植被盖度(0.20)、地表温度(0.50)、地表湿度(0.51) 5个维度上的生态位宽度最窄;而倭蛙(Nanorana pleskei)成体在牛粪数量(0.81)、植被高度(0.63)、植被盖度(0.47)、小水体距离(0.68) 4个维度上的生态位宽度最宽。在3种两栖类亚成体生态位宽度的比较中,岷山蟾蜍亚成体在牧场性质(0.66)、牛粪数量(0.58)、植被高度(0.64)、小水体距离(0.51)、地表湿度(0.79) 5个维度的上生态位宽度最宽;倭蛙亚成体在牧场性质(0.39)、牛粪数量(0.30)、地表温度(0.18)、地表湿度(0.33) 4个维度上的生态位宽度最窄。高原林蛙(Rana kukunoris)在地表温度(成体:0.62;亚成体:0.56)、地表湿度(成体:0.84;亚成体:0.60)两个维度上具有较大的生态位宽度值,而在小水体距离维度上(成体:0.27;亚成体:0.14)的生态位宽度值则很小。比较3种无尾两栖类在不同生长阶段(成体、亚成体)的生态位宽度,发现高原林蛙和倭蛙的亚成体对栖息环境的要求更高。3种两栖类空间资源利用的相似程度很高,高原林蛙与倭蛙之间的生态重叠度(0.87)较之它与岷山蟾蜍(0.81)的生态位重叠度更大。 2、两栖类的日活动节律:高原林蛙成体、亚成体、岷山蟾蜍亚成体活动的最低气温为0℃、2℃、8℃;岷山蟾蜍和高原林蛙亚成体出现的数量与气温成极显著的正相关(r=0.797, p<0.001;r=0.794, p<0.001),高原林蛙成体出现的数量与气温有一定相关性(r=0.456, p<0.05);晴天时两栖类的活动性明显高于阴天(p<0.001);多云转晴天气,高原林蛙和岷山蟾蜍亚成体出现两次日活动高峰,分别为中午12:30左右和下午15:30~16:30之间;多云天气,高原林蛙和岷山蟾蜍亚成体出现两次日活动高峰,分别为9:30~10:30之间和15:30~16:30之间。 3、两栖类的食物资源利用状况:春、秋两季,高原林蛙最主要的食物是蜉金龟科(Aphodiidae)昆虫,相对重要性指数(IRI)最高(春季:35.28%,秋季:28.57%),其次为昆虫的幼虫,以及双翅目的毛蚊科(Bibionidae)、蝇科(Muscidae)、丽蝇科(Calliphoridae)昆虫,秋季,蝗虫是高原林蛙食物组成中的重要部分;岷山蟾蜍最主要的食物是蚂蚁(IRI,春季:85.54%,秋季:49.70%),其次为蜉金龟科、象甲科(Curculionidae)、步甲科(Carabidae)、粪金龟科(Geotrupidae) 等鞘翅目昆虫;倭蛙春季的最主要食物也是蜉金龟科昆虫(IRI,春季:13.41%),其次为蚂蚁、毛蚊科昆虫、昆虫的幼虫以及狼蛛科(Lycosidae)。3种两栖类中,倭蛙的食性生态位宽度相对较宽(0.43),而岷山蟾蜍(0.09)和高原林蛙(0.22)的生态位宽度较窄,与春季相比,两栖类在秋季的食谱更宽。以利用食物种类为标准,春季高原林蛙与倭蛙的生态位重叠度(0.40)比它与岷山蟾蜍的生态位重叠度(0.33)更大。 4、畜牧业对两栖类食性及食物竞争格局的影响:以藏牦牛粪为食物或寄居场所的昆虫,如蜉金龟科、粪金龟科、毛蚊科、蝇科、丽蝇科昆虫和某些昆虫幼虫,是3种两栖类食物谱中最主要的组成部分,蜉金龟科昆虫在高原林蛙食谱中的比例更高,高原林蛙可能从畜牧业发展中获得更多的好处,使之在食物竞争方面处于优势地位。与无放牧样地相比,在有放牧样地的中,两栖类食谱中的蜉金龟科昆虫数量更多(有放牧:31.94%;无放牧:21.32%)、出现频率更高(有放牧:76.38%;无放牧:44%)。然而在不同样地上(有放牧/无放牧),两栖类的食物组成无显著性差异(P=0.188),两栖类的数量(P=0.075)、肥满度(P=0.537)均没有显著差别。 5、两栖类幼体的竞争策略:实验室条件下,通过活动性水平,变态时的体重、增长率和完成变态所需时间考察自然条件下常同水塘分布的中华蟾蜍(Bufo gargarizans)和高原林蛙蝌蚪的竞争策略。结果表明:中华蟾蜍蝌蚪在不同食物资源条件下,所选择的生存策略可能不同,即食物资源充足时,增加活动性获取更多食物,食物资源有限时,降低活动性且提前完成变态;与中华蟾蜍蝌蚪相比,在食物资源有限时高原林蛙蝌蚪获取食物能力可能更强。 This paper presented the study of competition of three amphibians (Rana kukunoris, Nanorana pleskei, Bufo minshanicus) based on spatial, temporal and dietary scales in Zoige wetland. We measured coexistence patterns of three amphibians and analyzed their ability of exploiting resource. Effects of grazing on the diet composition and diet competition of amphibians were analyzed by their diet composition during spring and autumn. Furthermore, we examined the competitive ability of larval common frogs (Rana kukunoris)and common toads(Bufo gargarizans) in a laboratory experiment, and analyzed their competitive strategies respectively. The results were as follows: 1 .The status of using spatial resource Niche breadths of B. minshanicus adults on 5 dimensional axes including character of pasture(0.41), number of yaks dung(0.42), vegetation coverage(0.20), temperature (0.50)and humidity(0.51) of ground surface were narrower than adults of R. kukunoris and N. pleskei. Niche breadths of B. minshanicus subadults were broader than R.kukunoris subadults and N.pleskei subadults on 5 dimensional axes including character of pasture (0.66), number of yaks dung (0.58), vegetation height (0.64), distance to small waterbodies (0.51), humidity of ground surface (0.79). Niche breadths of N. pleskei subadults were the narrowest in three anurans subadults on 4 dimensional axes including character of pasture (0.39), number of yaks dung (0.30), temperature (0.18) and humidity (0.33) of ground surface, niche breadths of N. pleskei adults were the broadest in three anurans adults on 4 dimensional axes including number of yaks dung (0.81), vegetation height (0.63) and coverage(0.47), distance to small waterbodies(0.68).Comparatively, niche breadths of R. kukunoris were broader on the two microclimate factors including temperature(adults:0.62;subadults:0.56) and humidity (adults:0.84;subadults:0.60)of ground surface, but was narrow on distance to small waterbodies(adults:0.27;subadults:0.14). Strategies for using habitat resource of adults and subadults of the three species anuran were different. Generally, subadults of R. kukunoris and N. pleskei needs better habitat condition. It was quite similar that three anurans exploited spatial resource, Niche overlap between R. kukunoris and N. pleskei (0.87) was greater than that between R. kukunoris and B.minshanicus(0.81). 2.Daily activity rhythm R. kukunoris audlts were active when air temperatures were as low as 0℃, R. kukunoris subadults were active at 2℃, B.minshanicus subaudlts were active at 8℃. Positive correlation was found between activities of amphibians and air temperature, Subadults of R.kukunoris, (r=0.797, p<0.001), Subadults,of,B.minshanicus, (r=0.794, p<0.001), andbadults,of,R.kukunoris(r=0.456, p<0.05).Amphibians were more active during sunny days than cloudy days. In cloudy turning into sunny, R. kukunoris and B.minshanicus subadults had two active peak: at noon about 12:30 and 15:30~16:30 pm; in cloudy, R. kukunoris and B.minshanicus subadult had two active peak too : 9:30~10:30am,15:30~16:30pm. 3.Diet analysis Aphodiidae was the most commonly consumed food item by R. kukunoris based on index of relative importance (IRI) during spring (35.28%) and autumn (28.57%) in Zogie wetland. Besides Aphodiidae, larval insect, dipterans such as Bibionidae, Muscidae, Calliphoridae also were important food item for R. kukunoris, in autumn, locust was one of important food item for R. kukunoris. The most important food item for B.minshanicus during spring (IRI:85.54%) and autumn (IRI:49.70%) was ants, following, was coleopterans, such as Aphodiidae, dung beetle. Aphodiidae (IRI:13.41%) were the most important consumed food item by N. pleskei during spring too, following, was ants and Bibionidae. Dietary breadth of N. pleskei (0.43) were greater than R. kukunoris (0.22) and B. minshanicus (0.09). As a whole, Dietary breadth of amphibians during aurumn were greater than spring. Based on prey item, dietary overlap between R. kukunoris and N. pleskei (0.40) was greater than that between R. kukunoris and B.minshanicus (0.33) during spring. 4.Effects of grazing on the diet composition and diet competition of amphibians Amphibians are an important part of the pasture ecosystems as prey and predator. In Zogie wetland, major diet of amphibians was closely associated with dung of yaks, for example, Aphodiidae, Bibionidae, Muscidae, dung beetle. Dung of yaks was major diet and habitat of these insects. Proportion of Aphodiidae was higher in diet composition of R. kukunoris than N. pleskei and B.minshanicus, with development of pasturage, R. kukunoris may have a diet competitive advantage over N. pleskei and B.minshanicus. Number of Aphodiidae in diet composition of amphibians was higher in samples with grazing (31.94%) than in those without grazing (21.32%). Occurrence Frequency of Aphodiidae in diet composition of amphibians was higher in samples with grazing (76.38%) than in those without grazing (44%). However, There was not significantly different on diet composition (P=0.188), and number (P=0.075) and the relative fatness (P=0.537) of amphibians between grazing samples and without grazing. 5.Competitive strategies of amphibian larvae I examined the competitive ability of larval toads (Bufo gargarizans) and frogs (Rana kukunoris) which co-occur in the nature pond by activity level, the growth rate and mass at metamorphosis and larval period in a laboratory experiment. The results suggest: In laborary, B.gargarizans adapted himself to different food level by changing activity. At high food level, B. gargarizans increased activity to gain more diet. At low food level, B. gargarizans decreased activity and achieved early metamorphosis. When food resource was limit, R. kukunoris could gain more food than B. gargarizans.

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沙蜥属(Phrynocephalus)的卵胎生类群主要分布在我国青藏高原,包括南疆沙蜥(P. forsythii)、西藏沙蜥(P. theobaldi)、红尾沙蜥(P. erythrurus)、贵德沙蜥(P. putjatia)和青海沙蜥(P. vlangalii)。其卵胎生生殖方式适应了高寒生境,与青藏高原隆升有关。纵观前人的研究,上述几种卵胎生沙蜥的分类、系统发育关系以及生物地理都还存在疑问。本文研究了分布在若尔盖湿地的青海沙蜥红原亚种(P. v hongyuanensis)以及分布在黄河上游其它地区青海沙蜥种组的地理分布格局,并探讨了其形成机制。 青海沙蜥在黄河上游主要分布于若尔盖湿地以及青海湖周边地区。若尔盖湿地青海沙蜥红原亚种的生境由于沼泽的形成被切割成不连续的斑块,通过遗传分析可以推测这种特殊生境对它们遗传结构的影响。其次,贵德沙蜥、青海沙蜥的青海湖周边各居群以及若尔盖湿地居群之间的系统地理格局还未见报道。因此本文以居群为单位,将它们作为一个复合体,通过系统地理研究,可以了解其种群遗传结构,据此分析相关的地质历史事件对其分布的影响。主要结果如下: 1. 若尔盖湿地青海沙蜥红原亚种的种群遗传结构: 共研究了三个地理单元(红原(HY)、辖曼(XM)、玛曲(MQ))的7个采集点的72个个体。所有ND4-tRNALeu序列比对得到785 bp的片断,定义了9种单倍型。结果显示总的核苷酸多样性较低,单倍型多样性较高。分子变异分析(AMOVA)显示3个单元间差异显著(P<0.01),遗传变异主要存在于地理单元间,占62.61%。除MQ单元,XM各居群与HY居群混杂在一起,单倍型网络图没有显示出单倍型和地理位置的对应关系。XM单元单倍型的不配对分布(Mismatch distribution)为明显左移的单峰,且Fu’s Fs test为负值,表明XM单元可能经历了近期种群扩张,有足够的时间积累单倍型的多态性,还不足以大幅提高核苷酸多样性,这是其单倍型多样性较高和核苷酸多样性较低的原因。MQ单元遗传多样性低而与其他单元显著分化,推测这与3万年前黄河在若尔盖玛曲之间贯通有关。近期沼泽的形成对XMb居群的隔离时间短,使得其遗传多样性低但还不足以形成大的遗传差异。无论黄河的贯通还是沼泽的形成其隔离形成的时间都不长,其作用改变了单倍型出现的频率,也出现了一些特有单倍型,但共享单倍型还广泛存在,还不足以使得不同居群之间形成较大的遗传距离。 2. 黄河上游青海沙蜥种组的分布格局与地史过程的关系: 黄河上游青海沙蜥种组包括贵德沙蜥、青海沙蜥指名亚种的青海湖周边各居群、青海沙蜥红原亚种若尔盖湿地居群、以及青海湖以西的部分居群(序列由Genbank下载获得),总计22个居群189个样品。所有ND4-tRNALeu序列比对得到703个位点,定义了39种单倍型。以南疆沙蜥为外群构建的贝叶斯树以及MP法构建的无根树,都分为A、B两大组。其中A包括若尔盖湿地居群以及玛多居群(A1)、青海湖以西的居群和兴海居群(A2)、西藏沙蜥;B包括青海湖以南的居群和天祝居群(B1)、青海湖以东北的居群(B2)。单倍型网络图分别对应了系统发育树上的各支。按照系统发育结果分组进行分子变异分析,得到组间变异占88.63%,各组间差异显著(P=0.000)。种群遗传结构分析得到,A1和B2可能经历了近期的种群扩张,前者扩张时间约为0.105-0.189 Ma B.P.(million years before present),后者为0.057-0.102 Ma B.P.,可能与末次间冰期的气候变暖有关。A2和B1对应的两个地理单元都具有较强的种群遗传结构,较为稳定。 青海沙蜥种组A、B两大支之间遗传距离大,分化明显,分化大约发生在4.29-2.38 Ma B.P.,推测青藏运动的A幕运动后复杂的地形变化可能是它们产生分化的原因。B1和B2分化大约发生在1.73-0.96 Ma B.P.,这与湟水流域构造运动发生的时间相符。在早、中更新世时期,B1支内部各居群可能有交流,中更新世末共和盆地出现的抬升以及河流溯源改道等事件可能是引起这支内部多个单倍型丢失的原因。A1、A2支的分化可能与倒数第三次冰期降临之后气候变冷、阿尼玛卿山的大冰帽有关。 The viviparous group of genus Phrynocephalus is mainly distributed in the Qinghai –Tibetan Plateau, including P. forsythii、P. theobaldi、P. erythrurus、P. putjatia and P. vlangalii. These species are adapted well to the cold clime there, and the origin of this group was the result of a vicariance event associated with the uplifting of the Qinghai -Tibetan Plateau. Although many works have been done, there are still several questions about classification、phylogenetic relationships and the biogeography of this group. The phylogeographic pattern of the P. vlangalii complex on the upper reaches of the Yellow River and the P. v. hongyuanensis in Zoige Wetland were studied in this thesis. On the upper reaches of the Yellow River, P. vlangalii complex are distributed in Zoige Wetland and the southeast and northeast region of Kuku-noor Lake. Because of the forming of the wetland in Zoige, the habitats for sand lizards are divided into many discontinuous ones, and it is necessary to analyze genetic structure in these unique habitats. The phylogeographic patter among P. putjatia、populations of P. vlangalii in the southeast region of Kuku-noor Lake and populations of P. vlangalii in Zoige Wetland hasn’t been studied yet, and the complicated geological events of the Plateau may play an important role in the populations’ diversity and species forming there. So these populations were gathered as a complex, and phylogeographic analysis were used to clarify these doubts. According to the two topics above, this thesis has two parts of results as follows: 1. Three geographic units of P. vlangalii hongyuanensis in Zoige Wetland were defined, and they were Xiaman (XM)、Hongyuan (HY) and Maqu (MQ). 785bp fragments of the mtDNA ND4-tRNAleu were determined from 72 samples and nine haplotypes were identified. As a whole, the nucleotide diversity was low,but the haplotype diversity was high. Analysis of molecular variance (AMOVA) showed that the three units were distinctly different(P<0.01),and 62.61% of the total genetic diversity was attributable to variation among units. There were 3 haplotypes shared among XM and HY,and no geographic clustering was observed except MQ from the TCS network. The results from the mismatch distribution analysis and Fu’s Fs test implied that there might be a recent population expansion in the XM unit, and this may be the reason why XM had a high haplotype diversity but a low nucleotide diversity. We estimate that the MQ and XMb have lower diversities because of some very recent geographic events, such as the formation of the Yellow river’s upriver and the Zoige Wetland. Although they are distinctly different, not enough time has passed for them to have diverged a great genetic distance. 2. 189 samples in 22 populations of P. vlangalii complex were collected, including P. putjatia、populations of P. vlangalii in the southeast and northeast region of Kuku-noor Lake、 populations of P. vlangalii in Zoige Wetland and the data from Genbank. 703bp ND4-tRNALeu sequences identified 39 haplotypes. P. forsythii was selected as outgroup, and both the Bayesian tree and the MP unrooted tree were divided into two groups(A、B). A included populations in Zoige Wetland and Xinghai(A1)、populations in the west of Kuku-noor Lake(A2)、P. theobaldi, and B included populations in the southeast of Kuku-noor Lake and Tianzhu(B1)、populations in the northeast of Kuku-noor Lake(B2). The haplotype network agreed with these groups. AMOVA showed that these five groups were distinctly different(P<0.01), and 88.63% of the total genetic diversity was attributable to variation among groups. There might be recent population expansion in A1 and A2, which corresponded to the dry climate of the last interglacial period. The expansion times were 0.189-0.105 Ma B.P. and 0.102-0.057 Ma B.P., respectively. A2 and B1 had strong genetic structure. The large genetic distance between A and B showed that they had been separated from each other for a long time(about 4.29-2.38 Ma B.P.), and it corresponded to the A phase of Qingzang Movement. The diversity between B1 and B2 at 1.73-0.96 Ma B.P. may be caused by the geological event in Huangshui valley. In early Pleistocene, populations in B1 may have gene flow because of geographic linkage, and later the uplift of the Plateau and the change of river route there made a few haplotypes lost. A1 and A2 were divided into two parts by A’nyemaqen Mountains at 0.66-0.37 Ma B.P., which maybe corresponded to glaciations at about 0.7 Ma B.P.

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本文考察了若尔盖高寒泥炭湿地公路对高原林蛙(Rana kukunoris)、倭蛙(Narorana pleskei)和岷山蟾蜍(Bufo minshanicus)的生态影响。分析了公路对两栖动物空间分布和栖息地利用的影响,并用IBM模型探讨其可能作用机制,考察了两栖动物公路死亡的季节差异及影响公路死亡空间分布的景观因素。最后通过对若尔盖高寒湿地两栖动物陆地核心栖息地的分析,为若尔盖路域栖息地的管理提供依据。 1. 对公路周边6个沼泽水凼群进行了调查,每个样地设置5条样线(距离公路10m、20m、50m、100m和150m)。调查表明,在繁殖季节(5月),距离公路距离对高原林蛙和倭蛙的相对数量都有显著作用,其效应明显大于其他各项栖息地环境参数。公路导致高原林蛙和倭蛙在公路周边种群密度降低,其相对数量从距离公路100m处到公路边缘一直呈现逐渐降低的趋势。在繁殖季节,若尔盖高寒湿地的公路生态影响域大约在100-150m之间,这一距离远远大于森林栖息地中公路对两栖类的生态影响域(35-40 m)。 在繁殖后期(9月),对公路周边16个草地样点的样线调查表明,公路对周边高原林蛙和倭蛙密度分布并未造成显著影响。 2. 二次模型的拟合表明繁殖季节高原林蛙和倭蛙在公路周边的密度分布符合钟型曲线。前人对森林公路两侧两栖类分布的研究也显示了类似的规律。我们通过基于个体的模型,模拟在了公路边缘100单位距离内的栖息地空间,栖息地环境质量呈梯度变化,动物个体在其中通过随机运动寻找适宜的栖息地。拟合结果表明,动物个体仅仅依照简单的运动规则寻找适宜栖息地,这种活动就可以导致公路周边栖息地中的动物分布曲线出现3个局部峰。公路周边两栖动物的钟型分布曲线可能仅仅是个体寻找适宜栖息地过程中出现的临时性群体分布模式。 3. 在若尔盖高寒湿地,公路交通造成了大量两栖类死亡。但是公路两栖类动物死亡的季节分布很不均匀:5月、8月和9月死亡数量很高,而7月和10月死亡数量却很低。这种季节性差异和两栖类各个生活史阶段的迁移运动有密切的关系。利用景观参数的逻辑斯蒂回归模型显示,距离公路1000-2000m范围内的湿草地比例对三种两栖类公路死亡概率均有很强的贡献。湿草地这一栖息地类型分类中有大量的沼泽水体,是两栖类重要的繁殖点和取食点。两栖类公路死亡概率湿草地的关系从一个侧面表明,要维持一个区域较高的两栖类种群数量,需要1000-2000m半径范围内存在大面积的湿草地。 4. 高原林蛙和岷山蟾蜍不同性别和年龄个体分布点的水体距离存在显著差异。不同种类、年龄的两栖类分布点距离水体距离的差异可能是由于对水体的依赖性造成的。而相同种类、年龄段的个体中,高原林蛙雌性、岷山蟾蜍亚成体和雌性的体重与分布点距水体距离有显著负相关,这可能是因为体重更大的个体对水体的依赖性更弱。考虑到过大的陆地核心栖息地面积在实际保护工作中存在操作上的困难,因此我们认为可以以水体周边90%个体的分布区为低限确定3种两栖类的最小陆地核心栖息地。但是,在同样的水体距离-两栖类密度分布格局下,水体的面积和分形参数对最小陆地核心栖息地半径的确定有一定影响。 Ecological effects of alpine wetland road on Rana kukunoris, Narorana pleskei, Bufo minshanicus was studied in Zoige wetland. The effects of road on distribution of amphibians and its possible underline mechanism was discussed based on empirical data and computer simulation. Road killed amphibians was surveyed in different season and those landscape factor which could have impact on road killing distribution was analyses. Core terrestrial habitat of amphibians in Zoige wetland was discussed in the consideration of conservation management. 1. Six pool groups was investigated in breeding season (May) of R. kukunoris, N. pleskei. Five transects at distance of 10m, 20m, 50m, 100m and 150m from road edge was surveyed in each pool groups. There was a significant effects of distance from road edge on relative counts of R. kukunoris, N. pleskei, which is much important than effects of other environmental factors. Road caused the density of R. kukunoris, N. pleskei decreased from distance of 100m from road to 10m from road. Road ecological effect zone of alpine wetland for amphibians is about 100-150m. It is much wider than those of forest roads, which is about 35-40m. However, studies on 16 grassland near road showed no significant effect of road on amphibians after breeding season (Sep.). 2. Quadratic model fit indicated that the distribution of R. kukunoris and N. Pleskei followed a hump like curve. Previous studies on forest road showed similar results. A 100×100 habitat with gradual environment besides road was simulated with a individual-based model, and animal seek for suitable habitat with stochastic locomotion in it. Simulation results indicated that 3 density peak of animal distribution can emergent followed a simply rules. The hump like density cure could be a temporal swarm pattern during the process of individual seeking for habitat. 3. Road traffic caused mass death of amphibians in Zoige wetland. There was much road killed amphibians in May, Aug and Sep than those in July and Oct. The fluctuation of road kill could be related with migration of amphibians between seasons. Logistic regression of landscape variables indicated that wet grassland in 1000-2000m is essential to predict the probability of road kill. Wet grassland is an important breeding and forage habitat for amphibians. It also indicated that mass wet grassland in 1000-2000m is essential for maintain a big amphibian population. 4. There was significant differences among distance from aquatic site of subadults, female and males of R. kukunoris and B. Minshanicus. Possibly, it was because of their dependence on water. There was a significant negative relationship between distance from aquatic site and individuals body mass. Estimates of core habitat that are too large may make it difficult to establish protective regulations. The smallest suitable terrestrial core habitats were defined as the terrestrial habitats used during migration to and from the wetlands, and for foraging by 90% of any life stage (adults, and subadults) in a season. However, even with the same amphibian distribution pattern along the distance from aquatic sites, the radii of smallest suitable terrestrial core habitats will be varied with the fractal parameters of aquatic site.

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From 5 May 2003 to early June 2005, nest site selection of Black-necked Cranes Grits nigricollis was studied at the Ruoergai Wetland Nature Reserve (RWNR), an important breeding area for the species in China. Results showed that the crane nests only in we

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One of the most endangered populations of Black-necked Cranes (Grus nigricollis), the central population, is declining due to habitat loss and degradation, but little is known about their space use patterns and habitat preferences. We examined the space use and habitat preferences of Black-necked Cranes during the winter of 2007-2008 at the Napahai wetland in northwest Yunnan, China, where approximately 300 Black-necked Cranes (>90% of the total central population) spent the winter. Euclidean distance analysis was employed to determine the habitat preferences of Black-necked Cranes, and a local nearest-neighbor, convex-hull construction method was used to examine space use. Our results indicate that Black-necked Cranes preferred shallow marsh and wet meadow habitats and avoided farmland and dry grassland. Core-use areas (50% isopleths) and total-use areas (100% isopleths) accounted for only 1.2% and 28.2% of the study area, respectively. We recommend that habitat protection efforts focus on shallow marsh and wet meadow habitats to maintain preferred foraging sites. Core-use areas, such as the primary foraging areas of Black-necked Cranes, should be designated as part of the core zone of the nature reserve. Monthly shifts in the core-use areas of the cranes also indicate that the reserve should be large enough to permit changes in space use. In addition to preserving habitat, government officials should also take measures to decrease human activity in areas used by foraging Black-necked Cranes.

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Phthalic acid esters (PAEs) have become widely diffused in the environment via the manufacturing process. Numerous experiments have shown that the bioaccumulation of PAEs occurred in the aquatic and terrestrial food chain; meanwhile, it was found that some of PAEs were considered as potential carcinogens, teratogens and mutagens. In this research, two vertical/reverse-vertical flow constructed wetland systems were set up to study its removal efficiency of dibutyl, phthalate (DBP) pollution. The results showed that the constructed wetland system could remove DBP effectively, and the removal rates reached nearly 100%. Substrate microorganism and enzymatic activities probably played key roles during DBP removal, and the removal of DBP probably mainly took place in the upper layer of chamber A in the constructed wetland systems. (C) 2007 Elsevier GmbH. All rights reserved.

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The effects of single Cd2+ and Pb2+, and combined Cd2+ and Pb2+ on dehydrogenase activity and polysaccharide content of the substrate biofilms in the integrated vertical-flow constructed wetland (IVCW) were studied. Dehydrogenase activities decreased linearly with the increasing concentrations of Cd2+ and Pb2+ at different times (6, 24, 72, and 120 h). The activities at both 6 and 24 h were significantly higher than that at 72 and 120 h in the case of single and combined treatments. The single Cd2+ and Pb2+ treatments significantly inhibited dehydrogenase activities at concentrations in excess of 20 mu mol/L Cd2+ and 80 mu mol/L Pb2+, respectively. The inhibitory effect of Cd2+ was much greater than that of Pb2+. At the same time, the combined treatment of Cd2+ and Pb2+ Significantly inhibited dehydrogenase activities at all five concentrations studied and the lowest combined concentration was 1.25 mu mol/L Cd2+ and 5 mu mol/L Pb2+. A synergistic effect of Cd2+ and Pb2+ was observed. On the other hand, polysaccharide contents varied unpredictably with the increasing concentrations of Cd2+ and Pb2+ and extended experimental time. There were no significant statistical differences within the range of concentration and time studied, whether singly or in combination. These results implied that the effects of heavy metals on biofilms should be a concern for the operation and maintenance of constructed wetlands.

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A L9 orthogonal array design involving 3 factors (C6H12O6, KNO3 and NaH2PO4) and 3 levels for each (C6H12O6: 0.2, 0.4 or 0.8 g/L; KNO3: 0.4, 0.8 or 1.6 g/L, NaH2PO4: 0.05, 0.1 or 0.2 g/L), was used to study the effects of nutrients on dehydrogenase activity and polysaccharide content of substrate biofilms in the integrated vertical-flow constructed wetland (IVCW). Results showed that C6H12O6 and KNO3 were the main factors for dehydrogenase activity and polysaccharide content of biofilms, respectively. The combinations of three nutrients at different concentrations had different effects on dehydrogenase activity and polysaccharide content of biofilms. The optimal combination for dehydrogenase activity was obtained by locating the concentrations Of C6H12O6, KNO3 and NaH2PO4 at 0.2, 0.8 and 0.05 g, and the optimal combination for polysaccharide content was obtained by locating the concentrations Of C6H12O6, KNO3 and NaH2PO4 at 0.2, 0.4 and 0.2 g/L, respectively. The corresponding maximum activity and polysaccharide content were 5.40 mu g TF/g substrate/12 h and 3454.6 mu g/g substrate, respectively. These results would provide the laboratory foundation for optimizing the purification function of the wetland systems.

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A comparative study was conducted to reveal the differentiate effects of eight different filter media including gravel, zeolites, anthracite, shale, vermiculite, ceramic filter media, blast furnace steel slag and round ceramsite. The study mainly related to the eight different filter media's removal performances of organic matter, nitrogen and phosphorus in the vertical flow constructed wetland simulated system, which treating wastewater at hydraulic loading rate of 1000-2500 mm/d. The results indicated that the removal effects were closely related to the physical and chemical properties of medium materials. Anthracite-filled system had the highest removal rate for the total organic carbon (TOC), up to 70%, and the removal rates of other systems ranged from 20% to 30%. As for the five-day biochemical oxygen demand (BOD5), anthracite-filled and steel slag-filled systems had the highest removal rates, also up to 70%, as well as other systems all exceeded 50%. At the same time, for the total nitrogen (TN) and NH4(+)-N, the zeolites-filled and ceramic-filled systems had the best performances with the removal rates of more than 70%, the other way round, the removal rates of other systems were only about 20%. The distinguishable effects were also observed in removal performances of total phosphorus (TP) and total dissoluble phosphorus (TDP). The removal rates of TP and TDP in steel slag-filled systems were more than 90%, a much higher value, followed by that of the anthracite-filled system, more than 60%, but those of other systems being the less. Our study provided a potential mechanism to optimize the filter media design for the vertical flow constructed wetlands.