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1.
This paper studied the winter habitat selection of red-crowned cranes (Grus japonensis) in Yancheng National Natural Reserve, Jiangsu Province. There were six types of habitat used by red-crowned cranes, i.e.
salt-works, aquiculture ponds, reed lands, grassy tidal lands, salting wormwood lands and wheat fields. The wheat field was
a new type of habitat used by red-crowned cranes. More than 70 percent of red-crowned cranes chose grassy tidal lands, salting
wormwood lands, and reed lands as their most important habitats. In recent years, the distribution of red-crowned cranes moved
southward gradually. Red-crowned cranes prefer artificial or semiartificial wetlands rather than original wetlands, successive
distribution was broken into fragments.
The project is supported by Jiangsu Province
Zhang Honghai, male, born in July 1967, associate professor, Department of Biology, Qufu Normal University, Qufu 273165, P.
R. China.
Responsible: Zhu Hong 相似文献
2.
Nest-site selection patterns of Red-crowned cranes(Grus japonensis) and the effects of environmental variables were studied during the years of 2002-2008 in Zhalong Nature Reserve,Qiqihar city,northeast China.The nest-site selection pattern of Red-crowned cranes included two orders and three choices:the choice of nest-site habitat type within the macro-habitat order,nest zone selection and nest-site micro-habitat selection within the micro-habitat order.Various habitats(such as Carex swamps and reed fire districts) can be selected as the nest sites for Red-crowned cranes,of which reed swamps(93.15%) are given a preference.Factor Analysis reveals that the micro-habitat selection are affected by four main factors:fire,security(concealment /disturbance),incubation(conditions,nest-material),and food.Further analysis reveals that Red-crowned cranes have certain adaptability to the changes of nesting habitat quality in the Zhalong wetlands.In conclusion,fire,reeds,and water were the most important variables for nest-site habitat selection of Red-crowned Cranes in Zhalong Nature Reserve. 相似文献
3.
雅鲁藏布江中游河谷黑颈鹤自然保护区功能区调整及其生态影响 总被引：2，自引：0，他引：2
黑颈鹤为我国濒危珍稀鸟类,西藏雅鲁藏布江中游河谷黑颈鹤自然保护区是黑颈鹤最主要的越冬栖息地。分析原有保护区在区划范围和功能分区方面存在的问题,提出保护区的保护范围和功能区的调整方案。调整结果：将非保护区黑颈鹤越冬栖息地的湖泊湿地和河谷农田湿地划入保护区实验区,将保护区范围内的山地、干线公路两侧和人口密集区等无黑颈鹤活动的区域划为非保护区。分析保护区范围调整后的生态影响,并就如何促进保护区的建设和发展提出建议。 相似文献
4.
【目的】研究兴凯湖不同栖息地水鸟特别是濒危鸟类如鹤鹳类群落组成差异,为兴凯湖水鸟保护管理提供科学依据。【方法】于2014年5月至2015年4月、 2017年12月采用直接计数法对湖岗、龙王庙、东北泡子以及青山水库4个区域6类栖息地水鸟群落进行系统调查,并对水鸟群落特征参数进行分析。【结果】兴凯湖湿地内共记录水鸟7目11科85种364 063只。湿地内水域面积最大,物种数最多,多样性指数最高,以雁形目和鸻形目鸟类最多;林地与灌丛面积最少,物种数最少;灌丛多样性指数最低,以鹭科鸟类为主。在4个区域,湖岗水鸟多样性最高,其次是龙王庙和东北泡子,青山水库多样性最低。由于不同区域的栖息地组成不同,水鸟数量存在着显著性差异。【结论】随着兴凯湖栖息地类型的改变与人类活动的加剧,特别是作为鹤鹳类主要的繁殖地龙王庙与东北泡子,农田耕地面积增多,而沼泽湿地与草甸面积减少,使得鸭类与鹤类数量大幅减少。建议需根据不同水鸟对栖息环境的适宜性需求,制定科学合理保护方案,进行有效保护。 相似文献
5.
黄河三角洲自然保护区丹顶鹤生境适宜性变化分析 总被引：2，自引：0，他引：2
生境丧失及破碎化是引起物种濒危和生物多样性降低的主要原因.基于地理信息系统和遥感技术,生成保护区丹顶鹤有无人为干扰下生境适宜性图,并选取一系列的景观格局指数,分析1992(2006年内保护区内丹顶鹤生境适宜性变化规律及其原因.结果表明,由于缺乏淡水来源,无论有无人为干扰,1999年丹顶鹤生境适宜性最差,适宜生境面积大量丧失,生境破碎化严重.14年来,保护区内的人为干扰不断加大,以道路干扰最为显著.人为干扰促使丹顶鹤生境质量下降,生境适宜性变得更差,并导致2006年生境适宜性劣于1992年.驱动保护区内丹顶鹤生境适宜性变化的主要影响因素是水源及人为活动. 相似文献
6.
7.
潮间带湿地有极其重要的生态服务功能，但随着全球极端气候的频繁发生和人工干预加剧，潮间带湿地面临着退化甚至消失的威胁。聚焦潮间带湿地再自然化生境恢复策略，尝试从时间维度、潮汐动力空间梯度、雨洪淹没和潮汐消落的动态变化中，分析潮间带湿地生境的动态特征及其景观影响因子。以粤港澳大湾区潮间带湿地为例，立足景观生态学，以基于自然的解决方案为构建原则，提出3种潮间带湿地再自然化的生境动态修复策略：保护和修复潮间带湿地的完整性，恢复潮间带湿地的景观风貌和恢复关键性生物生境。 相似文献
8.
Effects of silane coupling agent level and extraction treatment on the properties of UF-bonded reed and wheat straw particleboards 总被引：2，自引：0，他引：2
Guangping Han Kenji Umemura Ee Ding Wong Min Zhang Shuichi Kawai 《Journal of Wood Science》2001,47(1):18-23
Urea formaldehyde resin bonded reed and wheat particleboards with a density of 0.7g/cm3 were manufactured from two types of particle: fine and coarse particles. The effects of the silane coupling agent (SCA) level and ethanol-benzene (EB) treatment on the board properties were examined. For SCA, epoxide silane (SiEP) and amino silane (SiNH) were used for reed and wheat particles, respectively. The results are summarized as follows. (1) For both reed and wheat boards, the internal bond (IB) strength and thickness swelling (TS) were significantly improved at up to 5% SCA content, but the effectiveness of treatment kept constant at above 5%. (2) The level of SCA had little effect on the bending strength, especially for the boards composed of coarse particles. (3) EB treatment upgraded both the IB and TS of wheat board significantly. (4) SiEP incorporation improved the IB and TS of reed board significantly, whereas EB treatment was more effective for wheat board. (5) The dimensional stability of both reed and wheat boards under varying humidity could be improved by increasing the level of SCA and by EB treatment. EB treatment was more effective than SCA addition. 相似文献
9.
Upgrading of urea formaldehyde-bonded reed and wheat straw particleboards using silane coupling agents 总被引：3，自引：0，他引：3
Guangping Han Changwu Zhang Dongmei Zhang Kenji Umemura Shuichi Kawai 《Journal of Wood Science》1998,44(4):282-286
Reed and wheat straw particleboards bonded with urea formaldehyde (UF) resin were manufactured from two different material configurations (i.e., fine and coarse particles). The board densities were in the range of 0.550–.90g/cm3. The effects of particle size and board density on the board properties were examined. The properties of particleboard produced from fine particles were better than those made from coarse particles. An increase in board density resulted in a corresponding improvement in the board properties. The properties of OF bonded reed and wheat straw particleboards were relatively lower than those of commercial particleboards. Three silane coupling agents were used to improve the bondability between the reed and wheat particles and OF resin. Results of this study indicate that all the board properties were improved by the addition of silane coupling agent. The degree of improvement achieved from each coupling agent was different; epoxide silane was found to be more effective for reed straw particleboard, and amino silane was better for wheat straw particleboard. 相似文献
10.
Improvement mechanism of bondability in UF-bonded reed and wheat straw boards by silane coupling agent and extraction treatments 总被引：4，自引：0，他引：4
The effects of silane coupling agents and extractives on the wettability of reed and wheat straws were investigated. The inherent wettability of these materials was low but could be significantly improved by treating with silane coupling agents. The degree of improvement achieved by each silane coupling agent was different: Vinyl silane had almost no effect on wettability, epoxide silane was found to be more effective for reed straw, and amino silane was better for wheat straw. The wettability of these materials could also be improved by ethanol-benzene extraction, which resulted in more improvement in wheat straw than reed straw. The analyses of untreated reed and wheat straws by electron spectroscopy for chemical analysis (ESCA) revealed that there was much silicon on both the outer and inner surfaces of the former but only on the outer surface of the latter. The influence of hot-water extractives and silane coupling agents on the gelation time and pH of urea formaldehyde (UF) resin was also examined. The addition of extractives was found to increase the gelation time. Amino silane greatly retarded the gelation of OF resin, whereas epoxide and vinyl silanes had no influence on resin gelation. This retardation was found to be due to an increase in the pH of the resin. 相似文献
11.
鹤是湿地生态的重要指示物种。黄河三角洲生境多样性资源为鹤类栖息提供了优良的生态环境。但由于黄河三角洲湿地生态系统本身具有脆弱性、不稳定性、易变性的生态特点,在自然因素和人为因素的作用下,鹤类栖息生境常发生剧烈变化。本文从较长的时空尺度阐述了鹤对生境变化的适应性选择,介绍在生境退化、生态恶化区域实施的生境恢复与重建工作。 相似文献
12.
13.
Zhalong National Nature Reserve(Zhalong) is an important stopover for migratory birds.In recent decades,Zhalong has become the focus of researchers and public discussion in relation to irrigation.We studied relationships between birds and habitats at different water levels to guide development of more effective habitat management measures.We used line transects to survey bird numbers and distribution during April-May from 2005-2009 at Zhalong,and used cluster analysis and Chi-Square tests to analyze data.We recorded 139 bird species of 39 families and 13 orders during spring migration,including Anseriformes,Charadriiformes,Ciconiiformes,Columbiformes,Coraciiformes,Cuculiformes,Falconiformes,Galliformes,Gruiformes,Passeriformes,Piciformes,Podicipediformes,Strigiformes.Dominant vegetation and geographic region were the main influence factors of avian distribution.Different ecological groups preferred different water levels(p<0.01) and different habitat types(p<0.01).Grallatores,Natatores and Passeres were the main ecological groups in different wetland habitats,and reed marsh and lake are the main habitats for management.Grallatores preferred reed marsh and lake with water levels >30 cm and 5 15 cm.Natatores preferred lakes with deep water(>30 cm).Passeres preferred open forest and reed marsh with no surface water.Different avian ecological groups occupied specific habitats depending on water level and we recorded some overlaps in bird distribution. 相似文献
14.
Development of high-performance UF-bonded reed and wheat straw medium-density fiberboard 总被引：10，自引：1，他引：10
Guangping Han Shuichi Kawai Kenji Umemura Min Zhang Takahisa Honda 《Journal of Wood Science》2001,47(5):350-355
Urea formaldehyde resin-bonded reed and wheat straw fiberboards were produced from the fibers made under different steam cooking conditions in refining processes at densities of 500 and 700kg/m3. The effect of steam cooking conditions on the board properties was examined. The steam pressure and cooking time for reed and wheat straws were 0.4MPa/10min and 0.4MPa/5min, respectively, and 0.6MPa/3min and 0.6MPa/10min for both straws. The effect of steam cooking treatment before the fiber refining process on the wettability and weight losses of the straws was also investigated. The results indicated that the mechanical properties and linear expansion of the straw medium-density fiberboard (MDF) were improved with increasing steam cooking pressure and time during the refining process, whereas the thickness swelling (TS) did not vary much. The wettability of the straws was improved by cooking treatment. The steam cooking conditions had little effect on the wettability of the straw surfaces. For reed and wheat straws, the weight losses increased with increasing steam pressure and cooking time. In addition, it was found that the properties of MDF were significantly higher than those of particleboard, especially the internal bond (IB), where the IB values of MDF were more than 10 times higher than those of particleboard. All the properties of the straw MDF, except the TS of wheat board, can meet the requirement of JIS fiberboard standard. The high performances of MDF could be due to the improved wettability and the removal of extractives during the refining process. 相似文献
15.
将银杏木、杉木和麦秸秆、稻草、玉米芯等5种木本和禾草类植物纤维原料在氮气气氛中进行常规热解,采用气相色谱在线分析热解气体产物组分,采用气质联用技术分析冷却收集到的热解液体产物组分,并采用卡尔费休法测定热解液体产物中水分含量。在这些禾草类植物原料和木本植物原料的热解过程中,它们热解固体产物炭的得率都在30%左右;禾草类原料的热解液体产物得率在33%～42%,低于木本类原料的得率(45%～51%),而禾草类原料的热解气体产物得率在30%～39%,高于木本类原料(18%～24%)。在热解液体产物中,有机物组分主要为呋喃型化合物和酚类化合物;其中禾草类原料热解得到的液体产物中,呋喃类化合物的总质量分数在25%～33%高于木本植物原料得到的总含量,而酚类化合物的总质量分数较低为24%～30%。在植物原料热解的主要气体产物组分中,CO2和CO的形成主要与原料组分的热分解有关,而CH4和H2的形成则主要与植物原料热解所产生的焦油的进一步热解以及固体炭结构的转变有关。 相似文献
16.
Tidal freshwater forests in coastal regions of the southeastern United States are undergoing dieback and retreat from increasing tidal inundation and saltwater intrusion attributed to climate variability and sea-level rise. In many areas, tidal saltwater forests (mangroves) contrastingly are expanding landward in subtropical coastal reaches succeeding freshwater marsh and forest zones. Hydrological characteristics of these low-relief coastal forests in intertidal settings are dictated by the influence of tidal and freshwater forcing. In this paper, we describe the application of the Sea Level Over Proportional Elevation (SLOPE) model to predict coastal forest retreat and migration from projected sea-level rise based on a proxy relationship of saltmarsh/mangrove area and tidal range. The SLOPE model assumes that the sum area of saltmarsh/mangrove habitat along any given coastal reach is determined by the slope of the landform and vertical tide forcing. Model results indicated that saltmarsh and mangrove migration from sea-level rise will vary by county and watershed but greater in western Gulf States than in the eastern Gulf States where millions of hectares of coastal forest will be displaced over the next century with a near meter rise in relative sea level alone. Substantial losses of coastal forests will also occur in the eastern Gulf but mangrove forests in subtropical zones of Florida are expected to replace retreating freshwater forest and affect regional biodiversity. Accelerated global eustacy from climate change will compound the degree of predicted retreat and migration of coastal forests with expected implications for ecosystem management of State and Federal lands in the absence of adaptive coastal management. 相似文献
17.
内乡宝天曼自然保护区生物多样性空间特征研究 总被引：7，自引：0，他引：7
在对宝天曼自然保护区全面调查的基础上,采用样线,样地调查法,对保护区的生境多样性和物种多样性的空间分布特性进行了分析。结果表明,海拔,群落类型是影响保护区生物多样性的重要因素。 相似文献
18.
在珠海大面积围海、围湖造地的背景下,通过适应性研究和对场地原有基塘景观要素的提炼和运用,营造满足大门口水道雨洪安全、基塘生境修复、红树林保护、生态科普、市民休闲体验的多目标治理需求的湿地公园.基于需求和低干预下的土方平衡,现状基塘及塘埂的充分利用,基塘生境营造及观景设施构造等策略,完成了沿河道恢复咸淡水潮汐湿地,植物种... 相似文献
19.
Vertical distribution characteristics of soil organic carbon content in Caohai wetland ecosystem of Guizhou plateau,China 总被引：3，自引：0，他引：3
We selected four kinds of land use types from Caohai wetlands of Guizhou plateau (a total number of 32 soil profiles) to study the distribution characteristics of organic carbon content in soil. With different ways of land use, the organic carbon content of soil profiles and organic carbon density show the tendency of decreasing firstly and then increasing from top to bottom. With the increase of depth, the vertical difference becomes smaller first and then starts increasing. Land reclamation reduces the soil organic carbon content and density, changing its distribution structure in topsoil. The average content of organic carbon in Caohai wetlands are as follows: lake bed silt > marsh wetland > farmland > woodland, the average organic carbon content of lake bed silt, marsh wetland, farmland and woodland are 16.40, 2.94, 1.81 and 1.08 %, respectively. Land reclamation reduces the organic carbon content of soil, therefore the conversion of cultivated lands to wetlands and the increase of forest coverage will help to fix the organic carbon in soil and increase its reserves. 相似文献