【作者】 张曼胤；

【导师】 盛连喜； 崔丽娟；

【作者基本信息】 东北师范大学 ， 环境科学， 2008， 博士

【摘要】 本论文利用野外实地调查以及历史数据的整理和分析,解译了1986年、1996年和2006年三期江苏滨海地区的遥感影像,分析了江苏盐城滨海湿地不同时期的景观状况,研究了江苏盐城滨海湿地景观格局变化及其驱动因子,并结合江苏盐城国家级珍禽自然保护区历年丹顶鹤监测记录对滨海湿地景观格局变化下的丹顶鹤适宜生境进行了评价。结果显示:(1)在1986～2006年期间盐城滨海湿地景观变化明显。盐城滨海湿地的景观变化特征表现为以芦苇白茅湿地、碱蓬湿地以及河流等自然湿地的大幅减少和农田、水产养殖塘以及建筑用地等人为活动强度较高的土地利用方式的显著增加。1996～2006年自然湿地丧失的面积大于1986～1996年丧失的面积,自然湿地丧失的速率也明显快于1986～1996年。其中,米草湿地面积在1986～2006年期间米草湿地面积增加了近25倍。碱蓬湿地降幅达到79.65 %,芦苇白茅湿地降幅达到83.25 %,河流湿地降幅达到32.19 %,光滩湿地降幅为44.08 %,由于光滩湿地面积受潮位影响巨大,所以光滩湿地面积的实际降幅应小于44.08 %。而水产养殖塘、盐田等人工湿地和农田面积都呈现出逐渐增加的趋势。盐田湿地的面积变化幅度不大,水产养殖塘和农田是本地区人类对滨海湿地利用的主要方式,分别增幅为169.50 %和106.09 %。另外,建筑用地面积增幅达445.75 %。(2)从三个时期研究区域的景观格局指数来看,单个斑块面积减小,斑块的复杂性有所增加,斑块类型趋于分散,斑块之间的平均距离减小,斑块类型的邻接度变化不大,香农多样性指数增大,景观多样性增加,而香农均匀度指数变化不明显,景观指数的变化说明人为干扰对研究区域的影响在3个时期持续增长,景观破碎化明显。(3)盐城滨海湿地不同区域间景观变化差异显著。沿海5县市自然湿地面积变化的对比结果表明自然湿地呈现出一致的减少趋势,但其变化速率具有差异性。响水和滨海自然湿地面积较小,面积变化也较小。在盐城滨海湿地的主要分布区域射阳、大丰、东台三县市中。由于将辐射沙洲划分在东台县境内,所以东台所占湿地面积最大。大丰自然湿地减少的面积最高,其次是东台和射阳。在江苏盐城国家级珍禽自然保护区的核心区、缓冲区和实验区中,核心区保存最为完好,自然湿地面积减少的最小。核心区湿地景观的自然演替占主导的决定性地位。缓冲区在1986～1996年期间景观变化主要以滨海湿地的自然演替为主,而在1996～2006年期间,对自然湿地的大面积围垦成为了这一时期景观变化的主要影响因素。在1986～1996年期间,实验区的景观变化表现为自然湿地急剧减少,其中第五实验区自然湿地损失最大。在1996～2006年期间,自然湿地的损失进一步加剧,第五实验区的面积损失仍然最大。(4)滨海地区景观变化的原因以人类对自然湿地的围垦利用为主,接下来顺次为湿地的自然演替、土地利用方式的改变以及米草的生物入侵,而人工景观的自然化仅占相当小的比重。景观变化以人为因素为主导的驱动机制,人为因素主要包括国家及地方的湿地围垦政策,技术进步,人口变化及经济发展。自然驱动因子除了包括滨海湿地生态系统自身演替外,还包括海岸的侵蚀与淤长,米草的扩张以及海平面的变化,但与人为驱动相比仅处于次要地位。(5)根据野外调查,丹顶鹤的生境因子主要包括干扰、食物、水情况和植物覆被条件,其变化主要表现为干扰强度加重、面积扩大,食物丰度下降,植物覆被条件适宜性下降,浅积水区和湿润区面积的减少,深积水区和干燥区大面积增加。无干扰、食物丰富、植物覆被条件适宜的丹顶鹤栖息的生境类型总体上呈现减少的趋势,生境类型斑块数量减少率要小于几个生境类型面积的减少率,栖息地呈现破碎化的趋势。栖息地景观指数变化也同样表明,丹顶鹤的栖息地破碎化明显,栖息地的复杂性增加。1996～2006年的变化速度要明显高于1986～1996年,体现了人类干扰强度呈现加剧的趋势。本论文根据生境因子及人为影响建立了生境适宜性评价模型。从生境质量评价结果、实地调查及历年丹顶鹤同步调查记录显示,20年来丹顶鹤的生境类型及分布发生了较大的变化。主要表现为丹顶鹤适宜生境面积大量降低;适宜生境由连续分布转变为岛屿状分布,栖息地破碎化明显;丹顶鹤的分布有向核心区集中的趋势;人工湿地已经成为丹顶鹤的一种重要的生境类型。根据盐城滨海湿地景观变化分析结果和丹顶鹤生境评价结果,论文最后提出了江苏盐城滨海湿地及丹顶鹤栖息地的保护对策。更多还原

【Abstract】 In this paper, through interpretation, analysis and statistic to the three temporal TM remote sensing images in 1986, 1996 and 2006 with the collation and analysis of the field investigation and historical data, the landscape status of Yancheng costal wetland in Jiangsu Province were analyzed, the landscape pattern changes and their driving factors were researched, and also the habitat quality was assessed, based on the Red-crowned Crane monitoring records in Yancheng Nature Reserve and the changes of Yancheng costal wetland landscape. The results showed that:(1) Yancheng Coastal wetland landscape changed significantly in the period from 1986 to 2006. The characteristic of landscape changes in Yancheng coastal wetlands are shown as the natural wetlands declined substantially, such as the reed(Phragmites autralis) beaches, cogongrass (Imperata cylindrical varnajor) beaches and Suaeda glauca beaches, and the area with high intensive human activities increased significantly, such as the farmlands, aquaculture ponds and building sites. The loss area of natural wetlands from 1996 to 2006 was larger than the size of the loss from 1986 to 1996, and the loss of natural wetlands was significantly faster than the rate from 1986 to 1996. Among them, the area of spartina alterniflora beaches increase nearly 25 times from 1986 to 2006. The area of Suaeda glauca beaches dropped by 79.65 percent, the area of reed and cogongrass beaches dropped by 83.25 percent, the area of river wetlands dropped by 32.19 percent, and the bare flat beaches dropped by 44.08 percent. The area of bare flat beaches should decline less than 44.08 percent, for which was influenced by tide level in huge impact. The area of artificial wetlands, such as the aquaculture ponds, and farmlands increased gradually, and the area of salt fields changed little. The aquaculture ponds and farmlands were the main kinds of utilization mode in coastal area, the increasing rate of which were 169.50 percent and 106.09 percent respectively. In addition, the area of building sites increase by 445.75 percent.(2) According to the landscape pattern index in studying area during the three periods, the area of the single patch decreased, the complexity of it increased a little bit, the mean distance between the patches is reduced, the Interspersion and Juxtaposition Index changed little, the landscape diversity increased, and the evenness changed unnoticeable, which indicated that the disturbances in this area increased continued in the period, and the landscape fragmentation was increased with time.(3) The landscape of Yancheng Coastal wetlands in different regions changed significantly. The area of natural wetlands of the five coastal counties in Yancheng reduced continuously with different changed rate. There are less area of natural Wetlands in Xiangshui County and Binhai County and the area changes smaller also. The coastal wetland is widely distributed in Sheyang County, Dafeng County and Dongtai County. The wetland distributed in Dongtai County is the largest in this area, for the radial sand ridges area in the South Yellow Sea were put under Dongtai County in this study. The natural wetlands in Dafeng County reduced most and next to Dongtai County and Sheyang County. In the core, buffer and experimental zones of Yancheng Nature Reserve, the natural wetlands in core zones are still well preserved with the area of them reduced least, and the nature succession occupy the dominant position in the twenty years. During 1986-1996, the landscape change of buffer zone in Yancheng Nature Reserve relied mainly on the natural succession, and the natural wetlands reclamation of a large area became the main influence factor of landscape change during 1996-2006. The landscape change of experimental zone was shown as the natural wetlands were reduced sharply in the period from 1986 to 1996, and the losses of the natural wetlands were further aggravated during the period from 1996 to 2006. Among them the natural wetlands lost mostly in the 5th experimental zone during the twenty years, and the natural wetlands reclamation was the main influence factor of landscape change in the experimental zone.(4) The main factor of landscape change of Yancheng coastal wetlands was the natural wetlands reclamation, followed in descending order by natural succession of wetlands, land use changes and Spartina alterniflora invasion, and the artificial landscape naturalization only took quite small proportion. The reclamation intensity of natural wetlands in the period from 1996 to 2006 increased a little bit beyond the period from 1986 to 1996. The driving mechanism of landscape changes took human activity as the leading factor, which included reclamation policy of natural wetlands, technological progress, demographic changes and economic development. The landscape changes of natural driving factors included the costal wetland ecosystem succession, also included coastal erosion and siltation, spartina alterniflora invasion, and sea level changes, which held a subordinate position compared with the human activities.(5) Four major habitat factors for Red-Crowned Crane were identified by fieldwork, including disturbance, food, water regime and shelter in the study area,and these four habitat factors have indirect relationship with vegetation types, disturbance degree, food richness, water depth and shelter condition can reflect indirectly by vegetation types. The habitat factor changes were mainly reflected in the following: the increase of disturbance intensity and area, the abundance decline of foods, the appropriation decline of vegetation condition, the shrink of shallow water area and moist area, and the increase of deep water area and drying area. The habitat types with less disturbance, abundant foods and suitable vegetation cover decreased continuously, and the reduction rate of the patch numbers of different habitat types was smaller than it of the area of different habitat types, which showed that the habitat fragmentation degree strengthened gradually. The changes of landscape index showed that the habitat complexity increased and the landscape index change from 1996 to 2006 is faster than it from 1986 to 1996, which indicated that the disturbance is more serious. A habitat suitability index (HSI) model reflecting habitat factors and human impacts in landscape scale were built and five units were considered in the model, which were human disturbance, food richness, water regime in wetlands, vegetation shelter types and distance from road and residential area. According to the result of the habitat assessment, the field investigation and the historical records of the Red-Crown Crane investigation, the habitat types and distribution of the Red-Crowned Crane had changed greatly in the past twenty years: the area of suitable habitat reduced on a large area, the suitable habitat distributed continuously had changed into island-like distribution with significant habitat fragmentation, the distribution of the Red-Crowned Crane concentrated on the core zone of Yancheng Nature Reserve gradually, and the artificial wetlands has become a major habitat types of the Red-Crowned Crane.At last, according to the analysis of the landscape change of coastal wetlands in Yancheng and the result of habitat assessment of the Red-Crowned Crane, the protecting countermeasures of coastal wetlands and the habitats of the Red-Crowned Cranes in Yancheng were put forward.更多还原