辽河口翅碱蓬湿地退化及恢复机制研究

Research aboutdegradation and recovery of typical vegetation can reveal the interaction mechanism between biology and environment,balance the relationship between ecological protection and production development, and play an important role to maintain ecological civilization. LiaoheEstuarySuaedasalsa wetland is the frontvegetation system to the Bohaisea which is also the habitats of a variety of endangered species and the international famous red beach landscape. It is significant to maintain the sustainable development of the wetland.Recently, the wetland is broken and the area reduced rapidly all of which means the wetland has degraded. While few theory was established about that. This research will conduct at the positioning station. Geographic information system technology and investigation method are used to analyze the space-time rule of wetland degradation.Different degradation types are partitioned by rough set model. The main driving ones of human factors and natural factors are determined by set pair analysis method. Response of plants-water-soilwetland components is studied via set pairdegree of associationand dynamic analysis. Then degradation mechanism can be revealed from micro and macro perspective.Hydrological and salty experiments are conducted in different degradation areas to explore ecological restoration mechanism depending on the restored factor threshold proven by Gaussian Model. Finally dynamical wetland restoration will be modeled by analyzing the whole results via hydrodynamics and other models. The research will explore degradation mechanism of LiaoheEstuarySuaedasalsa wetland which will perfect the theory of vegetation degradation and conservation and provide the scientific basis for wetland management of sustainable utilization.

典型植被退化及其恢复研究可揭示生物与环境相互作用机制，平衡生态保护和生产发展关系，对生态文明意义深远。辽河口翅碱蓬湿地位于海陆交汇处，是多种濒危物种的栖息地和全球著名红海滩景观，对区域生态意义重大。近年来湿地面积锐减，斑块破碎，退化加剧，但是湿地退化及恢复的机制不清，严重影响湿地可持续利用。本研究依托湿地定位站，利用地理信息系统技术与调查方法分析翅碱蓬湿地近30年退化时空规律，以粗糙集模型划分退化类型区；以集对分析方法确定人为因素和自然因素作用下湿地退化的主要驱动因子，以集对关联度与动态度分析湿地植物-水-土各组分对退化的响应，从宏观和微观角度探明湿地退化机制；以高斯模型确定退化因子恢复阈值，在各退化区设置水文调控和水盐调控实验，以区域水动力学等模型建立湿地恢复动力学模型，探讨湿地恢复机制。研究结果将明确辽河口翅碱蓬湿地退化及恢复机制，完善植被退化及保育理论，为湿地管理经营提供科学依据。

辽河口翅碱蓬湿地是珍稀物种黑嘴鸥全球最大、最北栖息地，辽河口湿地向海的最后一道生物屏障，对维系湿地稳定及功能保障至关重要。近年来湿地面积锐减，景观破碎，功能退化，可持续利用受到制约。本项目严格按照任务书内容，采用地理信息系统、野外实验和控制试验等多种方法结合，明晰了该湿地退化的时空规律及分区，从宏观和微观角度揭示了退化机理，阐明了退化湿地生态修复机制。主要发现：（1）1985-2020年间辽河口翅碱蓬湿地面积存在阶段性波动但长时间序列上处于减小状态，2003年退化最严重，面积减少了87.42%；湿地景观空间分布结构持续破碎化、形状复杂化；湿地退化程度为Ⅲ级中度退化；基于粗糙集模型确定生境适宜性指数，高适宜和中适应性区域面积分别占16.94%和31.24%，表明退化湿地具有很高生态恢复潜力。（2）湿地退化人为驱动因素为农田开发、道路修建和水产养殖，关联度分别为0.460、0.340和0.329；自然驱动因素为平均气温和年均降水量，关联度分别为0.854、0.913；耐盐微生物Halomonas属、耐盐化能异养菌和嗜盐微生物Marinobacter Pelagibius类群受土壤间歇性曝露和水盐条件影响，微生物类群Gillisia和Cryobacterium受冻融和温度影响，二类微生物从微观角度影响翅碱蓬群落分布。（3）在不同退化区由翅碱蓬生长和生理指标确定，水深0cm～6cm和盐度0～600mmol·L-1为翅碱蓬生长环境条件阈值，水深3cm和盐度300mmol·L-1为最适；基质施入尿素、硫酸钾、过磷酸钙和复合肥改良后，土壤理化性质改善，盐分降低，4种酶活性增高；优化种质资源可有效提高翅碱蓬萌发率。实施水文调控、水盐调控、基质调控和种质资源优化可促进湿地生态修复。实施了以翅碱蓬恢复为核心的退养还滩技术33.35km2，翅碱蓬人工辅助种植生态修复面积6.67km2。