三峡库区典型流域生境质量时空演变特征与情景模拟

经济社会快速发展推动区域土地利用格局发生了深刻转变,对生境质量和生物多样性产生了巨大影响。准确评估和预测土地利用变化背景下生境质量的时空演变特征和未来发展趋势,对区域生物多样性保护和可持续发展具有重要意义。以三峡库区典型流域大宁河流域为研究区,基于2000年、2010年和2018年3期土地利用数据,分析了土地利用及生境质量的时空演变特征,并结合土地利用预测模型模拟了2034年自然发展、经济优先、生态保护3种情景下土地利用和生境质量的格局特征。结果表明：2000—2018年水田、旱地、草地面积呈总体下降的趋势,而林地、城镇用地、农村居民点、其他城镇用地呈整体增加趋势,揭示了城镇化建设和生态保护修复并存的土地利用变化格局;2000—2018年大宁河流域生境质量呈先降低后增加的趋势,整体格局相对稳定,但局部地区生境质量仍逐渐恶化,且两极化趋势明显;在未来情境中,2034年大宁河流域生境质量表现为生态保护情景>自然发展情景>经济优先情景,生态保护情境下流域局部和整体生境质量均得到显著提升,未来大宁河流域生物多样性保护和区域可持续发展规划中应更加注重统筹经济发展和生态保护之间的关系。     

基于土地利用格局变化的北京市生境质量时空演变研究

城市生境质量对生物多样性保护有至关重要的作用,以北京市为例分析2000—2015年北京市不同土地利用类型的空间分布特征和不同区域之间的差异,并借助In VEST-Habitat Quality模型评估了北京市4个时期(2000年、2005年、2010年和2015年)、4个区域(首都功能核心区、城市发展新区、城市功能拓展区、生态涵养发展区)的生境退化程度和生境质量变化情况。结果表明:(1)从2000年到2015年,建设用地增加了近40%,耕地、湿地是其快速扩张的主要来源,城市发展新区的建设用地增加了60%;(2)主要的生态用地(林地、草地、湿地)所占比例总体增加了5.71%,但是总体景观结构异质性减弱,斑块破碎化程度加大;(3)生境质量总体下降了2%,表现出明显的区域差异,首都功能核心区和生态涵养发展区的生境质量总值逐渐升高;生境退化度逐渐增加,最严重的区域在城市功能拓展区以及平原-山区交界地带。对区域生态服务价值评估的有益探索,为今后进一步城市景观格局的构建和优化提供依据和参考。     

闽江流域生境质量时空演变特征与预测研究

流域生境是生物生存和可持续发展的物质基础与环境保障,土地利用变化是影响生境质量的重要因素,分析土地利用与区域生境质量时空演变特征,对区域生物多样性保护与土地可持续利用具有重要意义。以闽江流域为研究区,基于2000-2015年的土地利用空间数据,构建CA-Markov模型模拟2025-2040年现有发展与生态保护情景下土地利用空间数据,利用InVEST模型分析2000-2040年生境质量空间格局。结果表明：（1）闽江流域森林覆盖率较高,现状条件下水田、旱地、针阔混交林、灌木林、草地与湿地面积呈下降趋势,其中草地减幅最大,达44.64%,针叶林、阔叶林、水域、建设用地、交通用地、采矿场与裸地面积呈上升趋势,其中交通用地涨幅最大,达到227.27%;模拟的土地利用Kappa系数达89.09%,模拟结果较好,生态保护情景在未来土地利用格局优化上优势明显。（2）研究期内闽江流域总体呈现较高的生境质量,基本维持在0.82的水平,城乡建设用地区域是生境质量低值的主要分布区,福州与长乐分布有最大的生境质量低值聚集区;生境质量分布与地形条件存在一定相关性,低值区多为海拔较低的区域。（3）2000-2015年闽江流域生境质量总体呈现衰退趋势,且降幅逐期升高,最高达0.24%;现有发展情景下降的趋势未得到有效缓解,生态保护情景下降趋势逐步有效缓解,同时生境质量为优等的栅格数量占比最大,最高达87.42%。（4）闽江流域上中游区域生境水平较下游高,现有发展情景下这种差距出现扩张趋势,生态保护情景下各区域则基本维持住2015年的生境质量水平。研究结果可为闽江流域土地资源可持续利用与生物多样性保护提供科学依据和决策参考,促进区域可持续发展。     

资源型城市土地利用转型及其对生境质量的影响——以乌海市为例

资源型城市前期发展导致了生境丧失或退化,实现高质量转型需要深入理解城市转型与生态环境质量之间的关系,土地利用转型特征及其对生境质量的影响规律研究为此提供依据与支撑。以资源型城市--乌海市为研究区,通过地学信息图谱和InVEST模型探究2005-2018年乌海市土地利用转型特征、生境质量时空变化及土地利用转型对生境质量的影响。结果表明：（1）2005-2018年乌海市土地利用变化趋势发生改变,土地利用转型明显,土地利用变化图谱单元数量逐渐增加78.14%,分布范围逐渐广泛。主要表现为草地与建设用地、采矿用地之间的相互转化,第一阶段（2005-2015年）草地大面积减少,建设用地和采矿用地大面积增加,第二阶段（2015-2018年）趋势相反。（2）乌海市生境质量变化呈现先强退化后弱提升趋势。2005-2015年乌海市18.75%的区域生境质量退化,提升面积较小;2015-2018年生境质量提升面积略大于退化面积。（3）2005-2015年草地向采矿用地、建设用地转化是区域生境质量降低的主要原因,2015-2018年区域生境质量提升的主导因素是采矿用地和建设用地向草地转化。研究结果揭示了资源型城市土地利用转型过程中生境质量的响应规律,可为资源型城市土地利用转型决策提供参考。     

基于InVEST模型的皖西大别山区生境质量时空演化及景观格局分析

新型城镇化及生态文明建设背景下,加强中国重要生态功能区的生境质量研究具有重要意义。以皖西大别山区舒城县为例,基于InVEST模型及地形位等方法进行生境质量时空演变与景观格局互动及梯度效应分析,结果表明:(1)1995—2015年,研究区生境质量指数从1995年的0.6392下降为2015年的0.6356,总体降幅不大;生境退化程度持续上升,由0.0133上升至0.0142。热点分析表明,生境质量较差的冷点区主要分布于东北部的城镇及其周边区域,质量较高的热点区主要位于西南部植被分布区;(2)生境质量及生境退化分布指数具有显著的地形位梯度效应。高生境质量分布指数与林地分布一致并随地形位梯度上升成主导优势,而低生境质量分布与建设用地和农地分布一致,并在低地形位梯度上占主导优势;(3)分区和整体生境质量与景观格局指数相关性显著,但不同区域内的二者之间相关性质各异。生境质量演化受地形和景观格局影响较大。研究结果对于大别山重要生态功能区的生境保护及生态系统功能调控具有一定的理论与实践价值。     

宁夏黄土丘陵区不同生态恢复生境地表甲虫多样性

为了解宁夏黄土丘陵区不同生境地表甲虫群落多样性变化规律及与环境因子的关系, 并探讨不同生态恢复措施对维持地表甲虫群落多样性的影响, 2013年7-8月, 作者利用陷阱法调查了该区6种生境内的地表甲虫群落多样性。结果表明: 灌草混交林地、乔灌混交林地、生态薪炭林地中地表甲虫物种丰富度和个体数量均较高, 天然封育草地、生态经济林地和水平农田中物种丰富度较低, 生态经济林地和水平农田中甲虫个体数量显著高于天然封育草地。不同生境间, 灌草混交林地、乔灌混交林地与生态薪炭林地之间、生态经济林地与水平农田之间甲虫群落组成相似性较高。多元回归分析表明, 草本层生物量、灌木层盖度及土壤含水量是影响甲虫物种丰富度的决定因素, 林冠层盖度和枯落物厚度是决定地表甲虫个体数量的重要因素。CCA分析表明, 枯落物盖度、枯落物厚度、林冠层盖度及草本层盖度是影响地表甲虫群落组成的重要环境因子。研究表明, 灌草混交林地为地表甲虫群落多样性维持较好的生境类型, 是宁夏黄土丘陵区典型生态恢复的最优模式。     

基于土地利用及植被覆盖变化的黄河源区生境质量时空变化特征

位于青藏高原腹地的黄河源地区生态环境脆弱,面临生物多样性锐减、生态系统退化等问题,黄河源区生态系统保护及其高质量发展已成为国家的重点战略之一。土地利用与植被覆盖是影响生境质量的重要因素,定量化土地利用方式、强度及格局和植被覆盖格局对生态质量影响的研究越来越受到关注,但其对黄河源区生态质量的耦合效应尚不明确。基于2000年和2015年黄河源区土地利用类型及生长季归一化植被指数（NDVI）,采用InVEST模型探究了不同时期黄河源区生境质量时空变化,并采用地理加权回归（GWR）模型揭示了生境质量对土地利用和植被覆盖变化的空间响应特征。结果表明,2000年与2015年土地利用类型变化主要为未利用土地向草地的转移。植被覆盖变化方面,源区生长季NDVI整体上升。从生境质量的空间分布来看,黄河源区生境质量总体呈现南高北低的空间格局,高值分布在南部及中部地区,低值分布在北部布青山、东北部高海拔区及黄河乡的黄河沿岸。相较于2000年,2015年黄河源区生境质量平均提高11.47%。草地面积和NDVI与生境质量均呈显著正相关关系,其中NDVI是提高黄河源区生境质量的重要驱动因子。研究结果突出了NDVI对提高黄河源区生境质量的主导作用,可为未来源区生态保护提供借鉴。     

小兴安岭——三江平原区生态问题辨析及山水林田湖草保护修复策略

为探讨山水林田湖草系统治理策略,实现生态系统服务价值的综合提升,以黑龙江省小兴安岭—三江平原区为研究对象,在分析研究区不同土地利用类型变化的基础上,基于不同土地利用类型的生态服务价值的变化,识别其面临的主要生态环境问题,提出研究区开展生态保护修复的策略。研究结果表明:(1)2005—2015年,小兴安岭—三江平原区耕地面积持续增加,林地、草地和湿地的面积持续下降,土地利用结构失衡。耕地面积主要由林地和草地转入,且主要分布在三江平原东部;(2)研究区生态系统服务价值从2005年的519.47亿元下降至2015年的495.71亿元。其中生物多样性以及土壤保持功能下降最为严重。土地利用类型的急剧变化,导致区域生态系统出现供给服务失衡、土壤保持和生物多样性功能下降及黑土退化等生态环境问题;(3)研究区山水林田湖草保护修复需突破行政边界的限制,合理规划工程布局,建立科学的评价体系和完善的监管制度;同时,需关注区域农田土壤质量变化,突出黑土地作为珍稀自然资源在山水林田湖草生态系统中的重要性。     

全国重要生态功能区生物多样性保护成效区域对比评估

国家重要生态功能区是国家主体功能区战略实施和生态保护红线划定的基础,关系到全国乃至全球范围的生态安全。开展大尺度生物多样性保护成效区域对比评估对促进物种栖息地科学管理、提升国家生物多样性保护水平具有较为重要的意义。本研究以2015年《全国生态功能区划》修编版划定的24个生物多样性保护生态功能区为研究对象,选取生态功能区内或邻近生态功能区的国家级自然保护区核心区作为参照区,利用InVEST模型计算多年参照区生境质量指数,并从中筛选出最大值,构建全国尺度的生境质量指数参照基准,在此基础上,采用空间叠加分析方法建立保护成效指数,定量分析了24个重要生态功能区生物多样性保护成效空间对比差异。研究结果表明:(1)基于参照基准的生物多样性保护成效区域对比评估方法可以较好地应用于全国尺度,全国重要生态功能区生境质量指数参照基准呈现明显的"西北低,东南高"的分布格局,而重要生态功能区生物多样性保护成效则表现出"西北高,东南低"的空间差异;(2)位于华东和华南地区的重要生态功能区生态环境本底状况较好,东北和华中地区的重要生态功能区居中,而西北和西南地区的重要生态功能区生态环境本底状况较差;(3)2015年西北和西南地区的重要生态功能区生境质量指数基本与参照基准持平,表现为生物多样性保护成效较好,华中和华南地区的重要生态功能区生境质量指数小幅度低于参照基准,体现保护效果居中,保护效果较差的重要生态功能区则位于东北与华东地区,其生境质量指数大幅度低于参照基准。通过对全国尺度重要生态功能区生物多样性保护成效区域对比评估,为进一步完善国家生物多样性保护成效的绩效考评机制和转移支付提供科学依据。     

闽三角城市群生态安全格局构建及城镇扩展模拟

在快速城镇化背景下,构建生态安全格局并探讨城镇用地扩展格局已成为保障区域生态安全和缓解生态保护与土地开发矛盾的重要手段。以闽三角城市群为例,基于景观安全格局原理和ArcGIS空间分析法,从综合水安全、生物保护安全、地质灾害安全以及游憩安全四个方面叠加构建"底线安全格局-缓冲安全格局-最优安全格局"三种不同安全水平的综合生态安全格局;然后结合SLEUTH模型,将不同生态安全格局情景作为约束条件融入其排除图层,对研究区2015—2030年的城镇用地空间扩展进行多情景模拟。研究表明:(1)底线安全格局、缓冲安全格局以及最优安全格局的面积为9305.51、7576.28、3482.73 km²,分别占闽三角城市群总面积的36.89%、30.03%、13.81%;(2)三种生态安全格局情景模拟下城镇用地均呈增长趋势,但增长速度均小于历史用地的增长速度,高安全格局约束下的新增城镇用地面积和增长速度均最小,表明将生态安全格局作为城镇发展的约束条件,在城镇土地开发中能够增强对生态空间的保护力度,维护区域生态安全,控制城镇蔓延。相关研究成果可为城镇开发边界管控与国土空间规划的编制提...     

基于土地覆盖和NDVI变化的拉萨河流域生境质量评估

气候变化和人类活动导致的土地覆盖和植被变化都会对生境质量产生影响。青藏高原是众多珍稀高原动植物的栖息地,具有重要的生物多样性维持价值。拉萨河流域是青藏高原经济最发达、人口最密集的核心地区,人类活动对生境质量带来的胁迫和压力持续增加。为揭示近些年来土地覆盖和植被变化对拉萨河流域生境质量的影响,选择生长季NDVI作为植被变化的指示因子,通过对不同植被类型各年份的生境适宜度进行修正,利用In VEST模型评估了拉萨河流域1990—2015年的生境质量时空变化。研究结果表明,1990—2015年拉萨河流域土地覆盖变化整体相对较小,其中人工表面和湿地面积增幅相对较大,分别为82.65%和32.40%;土地覆盖变化的转移方向主要为稀疏草地转化为草原和草甸、耕地转化为人工表面以及冰川/积雪转化为荒地。植被变化方面,1990—2000年,除流域中上游的裸岩、裸土地区和念青唐古拉山地区外,流域NDVI整体有较显著上升;而2000年以后略有下降。从生境质量的空间分布来看,高质量生境主要分布在流域下游、念青唐古拉山南侧河谷地区以及拉萨河源头等地区,低质量生境主要分布在拉萨市市辖区及周边、林周县县城及周边,以及流域中上游的荒地等地区。从时间变化上来看,1990—2000年,拉萨河流域整体生境质量指数从0.51上升到0.57; 2010年和2015年整体生境质量指数分别为0.56和0.55,较2000年略有下降。相比于土地覆盖变化,NDVI对生境质量变化的影响更为显著。     

基于MaxEnt模型的渤海湾沿岸鸻鹬类栖息地适宜性评价

渤海湾沿岸是鸻鹬类迁徙路线的重要栖息地。由于自然和人为原因,栖息地面积减少,质量恶化。因此,开展渤海湾沿岸鸻鹬类栖息地适宜性评价,对湿地生物多样性保护有重要意义。基于鸻鹬类点位信息和环境因子数据,利用MaxEnt模型对渤海湾沿岸2000年和2015年鸻鹬类栖息地适宜性进行评价。结果表明:土地利用/覆被、NDVI、年均气温、坡向是影响鸻鹬类分布的主要因子;鸻鹬类适宜栖息地主要分布在河北唐山南部和天津滨海地区。研究时段内渤海湾沿岸适宜栖息地面积总体有所下降,河北适宜栖息地面积下降,天津和山东增加;栖息地适宜性增加地区主要集中于天津南部、山东东南部,下降地区主要分布在河北丰南、黄骅及天津宁河县。该研究可识别渤海湾沿岸鸻鹬类适宜栖息地的分布范围及变化趋势,对该区域鸻鹬类保护及栖息地管理具有重要参考意义。     

Bush encroachment under three contrasting land-use practices in a mesic South African savanna

This study determined the effects of land-use practice had on the rate and extent of bush encroachment in a mesic savanna in KwaZulu-Natal, South Africa. Changes in woody cover were measured for 1 km² sites in areas under communal, commercial and conservation land-use systems for the period between 1937 and 2000. Land users from each area were interviewed to gain the histories of each area and to determine how the changes in woody cover had impacted them and whether anything was being done to counteract the spread of trees and shrubs on their land. Bush encroachment occurred across all three of the land-use types in the 67-year period between 1937 and 2000. The results showed that land-use practice had enormous impacts on the process of bush encroachment. The communal site showed a decrease in grass (21%) and tree (5%) cover and an increase in shrub cover (13%). At the commercial site, there was a considerable decrease in grass cover (46%) and moderate increase in shrub cover (10%) and a massive increase in tree cover (36%). The area under conservation showed a substantial decrease in grass cover (47%), a slight decrease in shrub cover (19%) and a massive increase in tree cover (66%). The perceived causes of these changes were fairly similar amongst the different land users. The changes were mostly not perceived to be a problem for the communal land users. The main advantages mentioned were increased woody resources for building and firewood and increased browse availability. The commercial and conservation land users perceived the changes to have significant negative connotations including the loss of grazing land and biodiversity and secondary invasion of encroached areas by alien plant species. Despite these perceptions, very little has been done to combat bush encroachment in the commercial and conservation land use systems.     

Low-Intensity Agricultural Landscapes in Transylvania Support High Butterfly Diversity: Implications for Conservation

European farmland biodiversity is declining due to land use changes towards agricultural intensification or abandonment. Some Eastern European farming systems have sustained traditional forms of use, resulting in high levels of biodiversity. However, global markets and international policies now imply rapid and major changes to these systems. To effectively protect farmland biodiversity, understanding landscape features which underpin species diversity is crucial. Focusing on butterflies, we addressed this question for a cultural-historic landscape in Southern Transylvania, Romania. Following a natural experiment, we randomly selected 120 survey sites in farmland, 60 each in grassland and arable land. We surveyed butterfly species richness and abundance by walking transects with four repeats in summer 2012. We analysed species composition using Detrended Correspondence Analysis. We modelled species richness, richness of functional groups, and abundance of selected species in response to topography, woody vegetation cover and heterogeneity at three spatial scales, using generalised linear mixed effects models. Species composition widely overlapped in grassland and arable land. Composition changed along gradients of heterogeneity at local and context scales, and of woody vegetation cover at context and landscape scales. The effect of local heterogeneity on species richness was positive in arable land, but negative in grassland. Plant species richness, and structural and topographic conditions at multiple scales explained species richness, richness of functional groups and species abundances. Our study revealed high conservation value of both grassland and arable land in low-intensity Eastern European farmland. Besides grassland, also heterogeneous arable land provides important habitat for butterflies. While butterfly diversity in arable land benefits from heterogeneity by small-scale structures, grasslands should be protected from fragmentation to provide sufficiently large areas for butterflies. These findings have important implications for EU agricultural and conservation policy. Most importantly, conservation management needs to consider entire landscapes, and implement appropriate measures at multiple spatial scales.     

Impact of land use on plant biodiversity and measures for biodiversity conservation in the Loess Plateau in China – a case study in a hilly-gully region of the Northern Loess Plateau

The Loess Plateau is a special natural–cultural unit in northern China. Intensive land use in the past has had, and forestation and grass planting at present will have inevitable impacts on plant biodiversity in the Loess Plateau. Based on the analysis of floristic features within three sampling sites with different land use practices and analysis of species richness among different land use types, we discuss impacts of land use on species richness and floristic features in the Northern Loess Plateau. The results drawn from this case study are as follows: (1) It appears that forestation and grass planting have had a positive influence on the local species diversity, but they have contributed little to the native vegetation in terms of conserving its floristic features. (2) Caragana intermedia shrubland, Pinus tabulaeformis forestland, and natural grassland have made important contributions to supporting indigenous species and maintaining local plant biodiversity. (3) There is a significant positive correlation between land use diversity and species richness. These results imply that practicing biodiversity conservation in situ is feasible and the suitable choice for the Loess Plateau. Concrete measures for biodiversity conservation in the area can include setting up small nature reserves and diversifying land use patterns to maintain as much habitat as possible for native vegetation. The artificial Hippophae rhamnoides shrubland should not be further promoted, considering its negative influence on biodiversity conservation.     

上海崇明岛前卫村沟渠生态修复示范工程评价

采用生物护坡技术、氧化塘系统和沸石处理系统,修建了上海崇明前卫村沟渠生态修复示范工程,并通过地表径流模拟实验及坡岸土壤参数、生物多样性、沟渠水体总氮和总磷含量等指标对该示范工程进行了评估.结果表明：与对照相比,使用灌丛垫技术修复后的坡岸土壤剪切力、紧实度和土壤湿度显著提高(P<0.05),坡岸植被延缓径流和去除悬浮物效果显著(P<0.05);使用柴笼技术修复后的坡岸土壤剪切力和悬浮物去除率显著提高(P<0.05),但对土壤湿度、紧实度和雨水径流的延滞作用不太明显.示范工程实施后,沟渠内水质得到明显改善,总氮和总磷含量显著下降(P<0.05),沟渠坡岸的生境质量和景观效果得到改善,生物多样性明显增加.采用土壤生物工程方法和其他生态修复技术集成可以稳定坡岸、改善沟渠的栖息地质量以及修复大城市郊区村镇沟渠的生态环境.     

Nest Site Selection by Greater Sage-Grouse in Mono County,California

ABSTRACT Loss of nesting habitat is believed to be a factor in the decline of greater sage-grouse (Centrocercus urophasianus) throughout its range. Few data are available for sage-grouse in Mono County, California, USA, in the most southwestern portion of the species’ range. We studied habitat selection of nesting sage-grouse in Mono County, California, from 2003 to 2005 by capturing and radiotracking females to identify nesting locations. We sampled vegetation at nest sites and randomly selected sites within 200 m of nests and within each of 5 subareas within Mono County. Nest sites were characterized by 42.4 ± 1.3% (x̄ ± SE) shrub canopy cover, 10.5 ± 1.0 cm residual grass height, and 2.7 ± 1.0% residual grass cover. Shrub cover was the only variable found to differentiate nest sites from randomly selected sites. Unlike some other studies, we did not find understory vegetation to be important for selecting nest sites. Mean shrub cover was 38.7 ± 1.5% at random sites within 200 m of nests and 33.6 ± 1.6% at random sites at the approximate scale of home ranges, indicating that nesting females selected nesting areas that contained denser shrubs than their home range, and nest sites that contained greater shrub cover than the vicinity immediately surrounding nests. Our results suggest that managers should consider managing for greater shrub cover in Mono County than what is currently called for in other parts of sage-grouse range and that management for sage-grouse habitat may need to be tied more closely to local conditions.     

The potential of military training areas for bird conservation in a central European landscape

European biodiversity has suffered from serious declines during the past few decades, with alterations of land use practices resulting in a loss of fine-scale habitat heterogeneity being a dominant driver. This heterogeneity was maintained by extensive landscape management, which has gradually been replaced by either intensive exploitation or land abandonment. It has been suggested that military training can generate habitat heterogeneity that may support the existence of species of conservation concern, but studies rigorously testing the real importance of military training areas for biodiversity are lacking. Here we address this issue by analyses of two datasets. First, we compared land cover classes between all large military training areas (MTAs) and surrounding control areas (CAs) of the same size in the Czech Republic using multivariate redundancy analysis. We found that the difference in land cover between MTAs and CAs was significant and represented the strongest gradient in land cover classes: from various farmland and artificial habitats typical for CAs to forest and scrubland-grassland mosaic typical for MTAs. Second, we selected one of these areas and compared bird species richness between the MTA and the nearby CA using generalized linear mixed effects models. We found that the number of species of conservation concern was significantly higher in the MTA than in the CA. With respect to habitats, bird species richness was significantly higher in the MTA than in the CA for open habitats, but not for forest habitats. Our results are thus consistent with the view that military training creates areas that are different from the surrounding landscape in terms of land cover, and that this difference translates to a suitability for species of conservation concern. It is remarkable that the positive influence of military training is confined to open habitats, which are subject to the most intensive military activities and also suffer the highest degree of deterioration in European landscapes.