鸟类群落对若尔盖高原湿地退化梯度的响应

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。     

排水疏干胁迫下若尔盖高原沼泽退化评价指标体系

沼泽退化评价指标体系研究是国际湿地科学研究前沿领域的关键科学问题之一.在长期野外考察的基础上,根据2009年3个排水疏干沼泽退化研究样带20个沼泽的植物群落生态观测和土壤分析数据,基于沼泽植物群落物种重要值的双向指示种分析(TWINSPAN),将沼泽样地划分为未受干扰(A型)、受长期低强度排水干扰(B～D型)和受短期高强度排水干扰(E～G型)3类,其中又可分为7个植物群落类型.采用主成分分析法(PCA)对沼泽退化进行分级,建立了若尔盖高原沼泽评价的植被指标体系(SVEI)和土壤指标体系(SSEI).基于SVEI,将沼泽划分为原始沼泽、轻度退化沼泽、中度退化沼泽和重度退化沼泽.基于SSEI,将红原县沼泽划分为原始沼泽、轻度退化沼泽和重度退化沼泽3个等级,将若尔盖县沼泽划分为轻度退化沼泽、中度退化沼泽和重度退化沼泽3个等级.SVEI或SSEI评价结果与TWINSPAN分类结果相似度均在70%以上,说明SVEI或SSEI对沼泽退化分级均具有较好的效果,可采用不同方法相结合的方式对高原沼泽进行综合评价.     

放牧胁迫下若尔盖高原沼泽退化特征及其影响因子

根据原生和退化沼泽水体、植被与土壤信息,将放牧胁迫下若尔盖高原沼泽划分为5个等级,即原始沼泽、轻度退化、中度退化、重度退化和极度退化沼泽,系统地研究了若尔盖高原沼泽的退化特征及其影响因子。沼泽退化特征表现为:退化沼泽水体总氮含量较高,硝态氮、总磷含量以及碱度、矿化度随沼泽退化程度加剧而上升。退化沼泽物种丰富度增加,群落组成和结构趋于多样化;群落水分生态型结构变化明显,中生植物逐渐取代沼生植物优势地位;沿沼泽退化梯度,植被演替速率降低。沼泽退化序列上,土壤含水率、毛管孔隙度、全氮含量降低,土壤容重、全磷和全钾含量上升;土壤垂直剖面上,退化沼泽较原始沼泽和轻度退化沼泽全量养分含量变化大,并且,全氮和全磷含量具有表聚性。退化沼泽环境指标PCA分析显示,沼泽退化受土壤养分和水分含量的影响较大。     

近40年来若尔盖高原高寒湿地景观格局变化

基于Apack软件,通过选取景观面积指数、景观多样性指数和景观破碎化指数等景观格局指数,从景观水平上研究了近40a来若尔盖高原高寒湿地景观空间分布格局特征的动态变化过程.结果表明:(1)高寒湿地景观空间格局以自然湿地景观为主要特征,自然湿地景观的斑块数和平均斑块面积均明显高于人工湿地景观.沼泽湿地景观斑块数最多,面积最大,所占比例高于95%;(2)高寒湿地景观具有高度的空间异质性.若尔盖县湿地景观的面积最大,占该区湿地景观总面积的近50%,湿地率也居五县之首;红原县和玛曲县次之;阿坝县和碌曲县最小;(3)高寒湿地景观面积呈先减少后增加的变化趋势.但与20世纪60年代相比,2000年湿地景观面积仍呈萎缩状态,总面积减少59857.83 hm2;(4)近40a来,若尔盖高原湿地景观呈集中连片分布,聚集度均高于0.95;优势度水平较高,但多样性指数水平较低.湿地景观的斑块数呈先下降后持平的变化趋势,而平均斑块面积则表现为增加的变化趋势;湿地景观分布质心也发生了明显的空间位移,经历了先向西北方向偏移12.54km;再向东南方向偏移了11.33km;最后又向北偏移了1.1km.     

内蒙古高原典型草原区河漫滩湿地植物群落退化表征

草原区河流河漫滩草甸是生物多样性表现最充分和生物生产力最高的地段, 但由于过度放牧利用, 绝大部分草甸处于退化状态。该文以锡林河流域中游的河漫滩草甸为研究对象, 比较分析了围封保育湿地与放牧退化湿地的群落组成、地上生物量, 以及共有植物种的植株高度、节间长、叶长、叶宽, 土壤含水量、容重, 群落地下根量及根的分布, 土壤微生物生物量碳、氮的变化。结果表明: 1)放牧使得湿地植物群落优势种发生变化, 原有湿生植物逐渐向旱生化转变, 同时地上及地下生物量明显降低。2)退化湿地的植物呈现显著小型化现象。3)放牧退化湿地的土壤含水量较围封保育湿地低, 其垂直分布及地下根的垂直分布也发生变化。在低河漫滩, 土壤水分随土层的增加而增加, 根量也趋于深层化。但在高河漫滩湿地, 土壤含水量接近典型草原, 根未出现深层化分布趋势。4)放牧践踏引起土壤容重和土壤紧实度增加。5)放牧使得低河漫滩湿地土壤微生物生物量增加, 而在过渡区及高河漫滩湿地, 放牧使得土壤微生物生物量碳、氮含量显著降低。     

若尔盖县湿地稳态转换的水文地貌生态阈值

以若尔盖县湿地为研究对象,在Google Earth影像和野外调查基础上获取若尔盖县人工沟渠的空间分布数据,并计算结构特征指数。从地形地貌和水文条件两个方面选择6项指标,利用熵值法筛选出对湿地稳态转换影响最大的指标并厘定生态阈值,包括理想值和临界值,通过1980-2015年土地利用数据识别若尔盖县湿地稳态转换区,最终基于乡镇尺度确定生态阈值调控范围,划分各乡镇湿地恢复优先性。结果表明：（1）若尔盖县存在四类湿地稳态转换区,其中稳态平衡区面积最大,占全县湿地面积的47.56%,退化转化区次之,占全县湿地面积的35.88%。（2）对若尔盖县湿地稳态转换影响最大的两项水文地貌生态指标为网络联通度和沟渠密度,权重分别为0.162和0.161。若尔盖县网络联通度的理想值为0.033、临界值为0.054;沟渠密度的理想值为0.011 km/km²、临界值为0.360 km/km²。（3）在若尔盖县需要进行湿地恢复的10个乡镇中,按湿地恢复优先性划分出3个三级恢复区、4个二级恢复区、3个一级恢复区,其中一级恢复区应优先恢复。     

若尔盖草甸退化对土壤碳、氮和碳稳定同位素的影响

为了解不同退化阶段高寒草甸土壤碳、氮和碳稳定同位素的差异,对若尔盖湿地内沼泽草甸、草原化草甸、退化草甸3个阶段土壤的碳、氮和碳稳定同位素进行了分析.结果表明:若尔盖湿地草甸土壤δ¹³C 值介于-26.21‰～-24.72‰之间,土壤δ¹³C 值随土层加深而增大.土壤δ¹³C 值与有机碳含量对数值呈线性负相关.表层土壤(0～10 cm)δ¹³C值大小顺序为草原化草甸>退化草甸>沼泽草甸,β值大小顺序为草原化草甸>沼泽草甸>退化草甸.沼泽草甸、草原化草甸、退化草甸0～30 cm 土壤碳含量分别为105.32、42.11和31.12 g·kg^-1,氮含量分别为8.74、3.41和2.81 g·kg^-1,C/N分别为11.26、11.23和10.89.随着草甸的退化,土壤碳、氮呈降低趋势,退化草甸C/N值低于沼泽草甸和草原化草甸.随着土层深度加深,碳、氮含量呈现降低趋势.草甸退化导致的土壤δ¹³C 值差异主要发生在表层0～10 cm.3个退化阶段中,退化草甸土壤的β值和C/N最低,表明退化草甸土壤矿化作用较强.     

中国旱灾风险定量评估

全球变暖及经济社会快速发展导致区域及全球性灾害风险增大,中国更是几乎每年都会遭受旱灾,因此,开展旱灾风险评估及影响因素研究对于区域经济社会可持续发展和灾害风险管理具有重要意义。以前的旱灾风险评估在评估方法以及评估指标选取方面都具有很强的主观性,导致风险评估结果具有强烈的不确定性,这在划定我国的高旱灾风险区域时可能会造成问题。基于旱灾风险的定义,合理假设"历史上旱灾损失高的地区遭受高旱灾损失的概率越大",引入历史旱灾损失资料对旱灾风险进行校正,构建了新的旱灾风险评估模型,揭示了中国旱灾风险的区域分异规律,并量化了各个影响因子的贡献水平。分析结果表明,我国存在5个显著的旱灾高风险区：东北地区、华北地区、西北地区东部、西南地区东部以及西北地区西部的小部分区域。影响因子分析进一步表明,高暴露度和高脆弱性是导致地区出现高旱灾风险的主要原因。     

放牧对若尔盖高原湿地CH4排放的影响

湿地是大气甲烷(CH_4)的主要排放源,而有关放牧对湿地CH_4排放的影响特征仍未得到足够的报道。因此,通过静态箱法,研究了放牧对四川省若尔盖高原湿地CH_4排放的影响,CH_4气体通过快速温室气体分析仪测量。结果表明:放牧样地和围栏内样地生长季CH_4排放量为(31.32±19.57)g/m~2和(30.31±23.46)g/m~2,它们之间无差异显著;但是集中放牧期间(7—9月),放牧样地(21.01±12.35)g/m~2较围栏内样地显著增加了CH_4排放量为54.3%。2014年生长季期间通过刈割植物模拟放牧表明两种刈割强度CH_4排放量为(5.01±5.37)g/m~2和(4.69±5.99)g/m~2,较未刈割样地(1.15±1.89)g/m~2增加了335.9%和308.0%,其原因可能是放牧或者刈割减少地表植物生物量,降低植物高度,缩短了CH_4排放的路径距离。该结果可为我国高原湿地保护与管理决策提供基础数据支撑。     

Ranking birdstrike risk: A case study at Huanghua International Airport, Changsha, China

Bird-aircraft collisions (birdstrikes) pose a major threat to aviation safety worldwide. The bird distribution at the airfield of Huanghua International Airport in Changsha, Hunan Province, China, was investigated between December of 2006 and December of 2008, to study birdstrike avoidance and aviation safety. A total of 60 bird species was found and their risks were assessed by a birdstrike ranking assessment system. The highest-risk species were Barn swallow (Hirundo rustica), Red-rumped swallow (H. daurica), Grey-headed lapwing (Vanellus cinereus), Pintail snipe (Gallinago stenura), Oriental skylark (Alauda gulgula), Little egret (Egretta garzetta), and Eurasian woodcock (Scolopax rusticola), whereas the lowest-risk species were Black-capped kingfisher (Halcyon pileata) and White-throated kingfisher (H. smyrnensis). Through a hierarchical cluster analysis, all species were classified as four groups: (1) the extremely high-risk group with a risk level between 84% and 100%, which includes bird species ranked from the 1st to the 16th, and is the priori group in birdstrike prevention; (2) the high-risk group with a risk level between 71% and 81%, which includes bird species ranked from the 17th to the 28th, and is the sub-prior group in birdstrikes; (3) the sub-high-risk group with a risk level between 60% and 69%, which includes bird species ranked from the 29th to the 43rd, and is the concern group in birdstrike prevention; (4) the low-risk group with a risk level between 60% and 69%, which includes bird species ranked from the 44th to the 60th, and is the negligible group in birdstrike prevention. Finally, the first 16 bird species with high-risk values, which are the main focus of birdstrike prevention, were categorized as six prevention groups by a hierarchical cluster analysis. Therefore, this study provides targeted implementations for birdstrike prevention at Huanghua International Airport, Changsha.     

Ranking birdstrike risk: A case study at Huanghua International Airport, Changsha, China

Bird-aircraft collisions (birdstrikes) pose a major threat to aviation safety worldwide. The bird distribution at the airfield of Huanghua International Airport in Changsha, Hunan Province, China, was investigated between December of 2006 and December of 2008, to study birdstrike avoidance and aviation safety. A total of 60 bird species was found and their risks were assessed by a birdstrike ranking assessment system. The highest-risk species were Barn swallow (Hirundo rustica), Red-rumped swallow (H. daurica), Grey-headed lapwing (Vanellus cinereus), Pintail snipe (Gallinago stenura), Oriental skylark (Alauda gulgula), Little egret (Egretta garzetta), and Eurasian woodcock (Scolopax rusticola), whereas the lowest-risk species were Black-capped kingfisher (Halcyon pileata) and White-throated kingfisher (H. smyrnensis). Through a hierarchical cluster analysis, all species were classified as four groups: (1) the extremely high-risk group with a risk level between 84% and 100%, which includes bird species ranked from the 1st to the 16th, and is the priori group in birdstrike prevention; (2) the high-risk group with a risk level between 71% and 81%, which includes bird species ranked from the 17th to the 28th, and is the sub-prior group in birdstrikes; (3) the sub-high-risk group with a risk level between 60% and 69%, which includes bird species ranked from the 29th to the 43rd, and is the concern group in birdstrike prevention; (4) the low-risk group with a risk level between 60% and 69%, which includes bird species ranked from the 44th to the 60th, and is the negligible group in birdstrike prevention. Finally, the first 16 bird species with high-risk values, which are the main focus of birdstrike prevention, were categorized as six prevention groups by a hierarchical cluster analysis. Therefore, this study provides targeted implementations for birdstrike prevention at Huanghua International Airport, Changsha.     

A HIVE model for regional integrated environmental risk assessment: A case study in China

Regional environmental risk assessment has been a significant means of environmental management and decision-making. To assess the regional integrated environmental risk at a nationwide scale, a new index system named the Hazard, Intensity, Vulnerability, and Effectiveness (HIVE) model was designed and evolved from previous researches. The HIVE model consisted of a relatively complete framework with accessible indexes related to environment and social economy, and it considered different risk sources, pathways, and receptors as well as the influence of the risk control. As an important segment of the assessment process, a simple gridding information diffusion method was also proposed to assess the diffusion effect of risk factors in nationwide rivers. Taking China as a case study, this study calculated the environmental risk value of every sub-unit. Through the clustering function of Statistical Package for Social Sciences and the visual representation of a geographic information system, the study area was divided into nine zones that were visualized on maps according to their different risk levels and risk characteristics. This study also identified the dominant factors of each zone, which could provide the foundation for regional environmental management. Moreover, the results implied some significant correlations between risk system components and the regional social economy in China.     

不同人为干扰下纳帕海湖滨湿地植被及土壤退化特征

以滇西北高原纳帕海湖滨退化湿地为研究对象,对比分析了人为隔断水源补给、牛羊过度放牧和家猪拱地三种人为干扰下湿地植被和土壤退化特征。结果表明：三种干扰方式下,纳帕海湖滨湿地植物群落类型多样性、物种丰富度、物种数、Shannon-Wiener指数、沼生植物重要值以及土壤有机质、全氮、速效氮、含水率、毛管孔隙度变化规律为：人为隔断水源补给＞牛羊过度放牧＞家猪拱地,而土壤容重和全钾含量变化规律完全相反。Pearson相关性分析表明,不同人为干扰下相同土壤指标之间相关性质和相关强度不同;CCA分析表明植物群落种类组成和分布与土壤含水率和全磷含量显著相关。以原生湿地样点为对照,人为隔断水源补给、牛羊过度放牧和家猪拱地样带土壤退化指数分别为-7.40%、-14.53%、-45.01%。认为纳帕海湖滨湿地退化是三种干扰协同作用结果,但作用程度不同,其顺序为家猪拱地＞牛羊过度放牧＞人为隔断水源补给。     

青藏高原高寒沼泽湿地在退化梯度上植物群落组成的改变对湿地水分状况的影响

对青藏高原东缘玛曲高寒沼泽湿地分属于15科的47种主要植物进行光合测定, 结合对不同退化类型植物群落的样方调查, 分析了各种植物之间以及不同功能群之间的净光合速率、气孔导度、蒸腾速率和水分利用效率等光合参数的差异。结果表明: 1)玛曲高寒湿地的主要物种在净光合速率、气孔导度、蒸腾速率和水分利用效率4个光合特性参数上的差异显著, 表明各植物种以各自独特的方式适应高寒湿地环境; 在功能群水平上, 各功能群之间的差异亦显著。光合速率从大到小依次为禾草>莎草>豆科和其他双子叶类杂草, 水分利用效率则是莎草>禾草>豆科和其他双子叶类杂草; 2)湿地退化导致其群落组成发生明显改变, 其中最明显的特点是双子叶类杂草的比例大大增加; 而双子叶类杂草普遍较低的水分利用效率将会增大土壤水分通过光合作用的蒸腾散失, 在大气降水对水分补充变化不大的条件下, 这将会进一步加剧群落生境的干旱化, 不利于退化湿地的恢复和附近湿地的保护。研究结果表明, 在湿地保护和退化湿地恢复过程中, 典型湿地土著物种的保存和补充具有重要意义。     

滇西北高原纳帕海湖滨湿地退化特征、规律与过程

采用双向指示种分析(TWINSPAN)和典范对应分析(CCA)方法,研究了滇西北高原纳帕海湖滨湿地退化特征、规律与过程.结果表明: 纳帕海湖滨湿地植物群落可以划分为4个群丛,群落演替规律为水生植物群落→沼泽植物群落→沼泽化草甸植物群落→草甸植物群落.随植物群落演替,群落盖度、密度、多样性指数、物种丰富度和地上生物量均增大,群落高度减小;植物水分生态型演替规律为水生植物→沼生植物→湿生植物→中生植物.随群落演替,湿地水体矿化度、硬度和碱度均降低,氨氮和总磷含量升高,总氮和硝态氮含量变化不明显;土壤pH、有机质和全氮含量逐渐降低,全磷和全钾含量逐渐升高,速效氮和速效磷含量先增大后减小.CCA分析表明,群落结构和物种组成主要受水分梯度影响,土壤pH、全磷和湿地水的总氮、氨氮对湿地植物物种分布和群落演替影响显著.     

生态保护红线区干扰退化风险评价——以安徽省为例

评估生态保护红线斑块受人类干扰的潜在退化风险,可为差异化、精细化的红线监管方案拟定提供科学依据。以安徽省域为例,基于InVEST模型,定量分析了2017年农田、城镇、矿区、交通干线等风险源对红线内各生境受体的干扰退化风险度。结论如下:全省和红线内受人类干扰退化风险由高到低的生境类型依次是农田、草地、湿地和林地。生态保护红线内人类干扰退化风险较全省平均水平更低。全省整体干扰退化风险指数呈现"北高南低"的格局。高风险区集中在合肥城区、芜马城区、淮蚌城区周边,两淮矿区及周边,低风险区则主要分布在皖西和皖南山区、巢湖湖区、沿江沿淮湖区等。干扰退化风险较高的红线斑块主要为合肥北部淠河——滁河干渠和董大水库水源地红线,铜陵市郊区棋盘山红线,长江干流芜马段自然岸线红线,淮河干流淮蚌段水体及岸线红线,阜阳城区颍河及周边湿地红线,皇藏峪西部宿淮交界处山体红线,宿州市砀山县城区东南部红线等,建议重点监管,防控人类干扰导致的生态风险。     

鄂尔多斯桃力庙-阿拉善湾海子湿地鸟类群落研究与湿地生境评估

近年来的野外工作结果表明,桃力庙 － 阿拉善湾海子(以下简称桃 － 阿海子)对于遗鸥鄂尔多斯种群的生存具有特别重要的意义,出现于那里的湿地鸟类集中地反映了鄂尔多斯荒漠型湿地鸟类群落的特点;鉴于我国于1992年7月已成为《具国际重要意义特别是作为水禽栖息地的湿地公约》(简称《拉姆萨公约》)的缔约国,本项研究比照《公约》所推荐的评判标准对桃 阿海子作了评估,提出该地点依据《公约》标准应被列入《国际重要湿地名录》。     

放牧干扰下若尔盖高原沼泽湿地植被种类组成及演替模式

以若尔盖高原退化沼泽植被为研究对象,应用多重比较、双因素方差分析、物种累积曲线、PCA排序、方差分解等方法分析了不同放牧压力、放牧季节下物种丰富度、多度、生活型组成、群落演替的变化。结果表明:不同放牧季节物种丰富度格局不尽相同,其中6、9、10月在各牧压梯度间无显著差异,7、8月均以极重度和极度阶段(中生草甸)的最高,原生沼泽的最低。在物种累积速率上,沿牧压梯度以极重度和极度阶段的最高,沿放牧季节以7、8月最高;双因素方差分析结果进一步表明物种丰富度与放牧季节无显著关系,但与放牧压力关系显著。放牧压力和放牧季节共解释了物种多度总方差的47.6%,其中放牧压力解释了50.1%,放牧季节以及二者方差交集均为负值;沿牧压梯度,沼泽植被逆向演替模式倾向于沼泽→草甸,沼泽化草甸阶段不明显,但是演替方向未发生变化,建群种替代规律为:乌拉草→木里苔草→栗褐苔草,生活型组成中直立型植物比例较少,莲座型和匍匐型植物增加。总之,放牧季节对物种丰富度无显著影响,但在一定程度上改变了其牧压梯度格局,降低了物种累积速率。放牧压力改变了群落物种丰富度、生活型组成和演替模式,但放牧可能仅为沼泽植物群落物种多样性格局和演替的驱动力之一。     

若尔盖高原沼泽土和草甸风沙土细菌16S rDNA PCR-RFLP和系统发育分析

采用稀释平板法从若尔盖高原沼泽土和草甸风沙土分离获得66株细菌,在16S rDNA PCR-RFLP分析的基础上,测定了22株代表菌株的16S rDNA序列,构建了供试细菌的系统发育关系。16S rDNA PCR-RFLP分析中,在78%相似性水平处,除REG14,REG20,REG22和REG55单独成群外,其余菌株分为8个遗传群,其中,群Ⅰ和群Ⅳ最大,均有15个菌株,其次是群Ⅷ,由11个菌株组成,其余21个菌株分布于5个群内。对22个代表菌株16SrDNA全序列系统发育表明,这些菌株分布于不同的系统发育分支。其中,以芽孢杆菌属(Bacillus)、假单胞菌属(Pseudomonas)和分枝杆菌属(Mycobacterium)为主,其余菌株分布于Lysinibacillus属、中华根瘤菌属(Sinorhizobium)、不动杆菌(Acinetobacter)、固氮菌属(Azotobacter)、红球菌属(Rhodococcus)、微球菌属(Micrococcus)和醋酸杆菌属(Acetobacter)等7个属。     

Rapid risk assessment of wetland degradation and loss in low-lying coastal zone of Shanghai,China

Coastal wetlands are facing an increasingly high risk of degradation and loss due to a wide variety of human activities and natural processes. Human encroachment, including land reclamation, drainage, and introduction of invasive species, has direct negative effects on wetlands, mainly through changes in hydrology and vegetation. Additionally, accelerated sea level rise (SLR) can result in flooding of wetlands in low-lying coastal zones. In this study, we present a rapid risk assessment method for coastal wetland loss and degradation. The main stress factors, i.e., urban sprawl, agriculture, coastal erosion, and SLR, have been examined and quantified through remote sensing and geographic information system spatial analysis. A weighted factor-based linear model has been used to evaluate the spatial risk levels of wetland loss. The proposed methodology is applied to the low-lying coastal wetlands of Hangzhou Bay in Shanghai, China. The results show that the regions closer to the sea have relatively higher risk levels on the landward side of the coastline, but relatively low risk levels on the seaward side of the coastline. This work emphasizes the need to sustainably use and protect wetlands in order to reduce disaster risks and contribute to the improvement of human well-being.