Impacts of multi-scenario land use change on ecosystem services and ecological security pattern: A case study of the Yellow River Delta

The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes(LUCC), impacting ecosystem services(ES) and ecological security patterns(ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development(NDS), economic development(EDS), and ecological protection scenarios(EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate:(1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies.(2) From 2010 to 2020, improvements were observed in carbon storage,water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES.(3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources,corridors, and pinchpoints, totaling 582.89 km^(2), 645.03 km^(2),and 64.43 km^(2), respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development.

Dynamics of Saline-alkali Land and Its Ecological Regionalization in Western Songnen Plain, China

As the important reserve land resources for food production,saline-alkali land should play a significant role to ensure the national food security in the context of global food crisis. The western Songnen Plain is one of main distribution regions of saline-alkali land in China,with great potential in agricultural development. In this study,the extent,transformation,spatial distribution and temporal change of saline-alkali land in the western Songnen Plain during 1954–2005 were investigated by using remote sensing and GIS spatial analysis methods. Saline-alkali land change was detected from a temporal series of topographic maps in 1954,satellite images of Landsat MSS in 1976,Landsat TM/ETM in 1988,2000 and 2005 through artificial visual interpretation. The results indicated a significant expansion in saline-alkali land area and aggravation in salinization. The area of saline-alkali land had increased from 401.48×103 ha in 1954 to 1 097.45×103 ha in 2005. While the ratio of light,moderate and serious salinized land areas changed from 6.72︰2.92︰1.00 to 1.25︰1.06︰1.00 in the study period. Grassland,cropland,swampland and water body were the major land use and land cover types from which saline-alkali land transformed. And the secondary salinization occured mainly in Da′an City,Tongyu County,Changling County,Daqing City,Dorbod Mongolian Autonomous County and Zhaoyuan County. Finally,seven large ecoregions and 14 corresponding sub-ecoregions were delineated out based on spatio-temopral dynamic characteristics of saline-alkali land and geo-relational environmental attributes. According to the results,measures of amelioration and ways of development of saline-alkali land in the western Songnen Plain were put forward.

Strategies for Safe Land Use of the Three Gorges Reservoir Area (Chongqing Section)——With the Restoration of Degraded Forest Landscapes as a Study Case

As a key for constructing ecologically safe scenery, forest landscape pattern in Chongqing Section of the Three Gorges has shown degradation, fragmentation and revision of varying degrees. To ensure normal and safe operation of the Three Gorges, and meet requirements of integrated development strategies for ecological and economic effects in Chongqing City on the ecological security of land use in Chongqing section of the Three Gorges, the following points should be attached more importance in making future strategies for an ecologically safe land use pattern with the restoration of degraded forest landscape as its starting point:a. Ecological effects and economic functions that can be supplied by forest landscape elements in different restoration patterns should be understood to obtain background effect of the ecological security pattern scenario of land use in the reservoir region; b. Relationship between restoration of degraded forest landscapes and serious ecological interference factors such as degradation background, artificial disturbance and engineering stress, should be simulated to figure out the influence of natural or artificial driving factors on landscape pattern, determine the future restoration mode for the degraded forest landscapes in the reservoir region, so as to facilitate the construction of great ecological-economic security pattern of the Three Gorges. The findings will provide scientific basis for the decision-making in building an ecologically safe land use pattern in the Three Gorges reservoir area (Chongqing), when using the degradation of forest landscape restoration as a carrier at present or in the future. Further, they will help realize the development goals of "Livable Chongqing, Expedite Chongqing, Forestry Chongqing, Safe Chongqing and Healthy Chongqing".

Geographical Information System-Based Assessment of Ecological Security in Changbai Mountain Region

Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional security and social stability.In recent years,land use patterns in the Changbai Mountain region have changed significantly with intensive human activities,and consequently led to increasing problems in regional ecological security.Based on the Pressure-State-Impact-Response(PSIR) model and the mathematical method of catastrophe progression supported by geographical information system(GIS),the ecological security situation of the study area under land use and cover change(LUCC) was evaluated.The results indicated that the ecological security in Changbai Mountain region varied nonlinearly,which got better from 1990 to 2000 but became worse from 2000 to 2007,the ecological security levels in Changbai Mountain region were mainly medium and medium to low during the past 17 years,with higher values of Ecological Security Index(ESI) in the central region and lower values in the east and west,the ecological security situation was more serious in the settlements and river valleys,where the LUCC was most remarkable.

Road Impacts on Spatial Patterns of Land Use and Landscape Fragmentation in Three Parallel Rivers Region,Yunnan Province,China

The structure and function of network is a central issue in landscape ecology.Road networks with hierarchical structure are crucial for understanding landscape dynamics.In this study,we compared the distribution of national road,provincial road,county road and rural road in the Three Parallel Rivers Region(TPRR)in Yunnan Province of China,and estimated the effect of roads(and other factors)on the spatial patterns of land use and land cover with logistic regression.In addition,we analyzed the land use and land cover change(LUCC)and landscape fragmentation in 1989–2005 along a buffer zone of the primary traffic corridor,national road G214.The results showed that,county and rural roads had much higher percentage of length extending into more natural habitats at higher elevation and steeper slope,compared with the higher level roads in this region.While the distributions of natural land cover types were dominated by environmental factors,human land use types i.e.,building land and farmland types were significantly related with roads,linking more closely with lower level roads.The LUCC dynamics(1989–2005)of the G214 buffer zone showed a general trend of land transformation from conifer forests and valley arid shrubs to building land and farmland,and from ice and snow to alpine shrubs and forests.With the length of G214 unchanged during the time,the overall landscape pattern changed little in the buffer zone,but habitat fragmentation and area decrease had occurred for the natural vegetation types,in contrast to patch mergence and expansion of human land use types,and landscape fragmentation was intensified above 2500 m a.s.l.but declined below the elevation.The results indicated the dynamics of landscape composition and patch type level distribution in spite of the stability of the overall landscape pattern,and implied the potential role of roads,especially the low level roads on landscape changes.

Land Use Change During 1960～2000 Period and itsEco-environmental Effects in the Middle and UpperReaches of the Yangtze River:a Case Study in YiliangCounty,Yunnan,China

Land use/land cover change (LUCC) is a focus of the research of global environmental changes. The middle and upper reaches of the Yangtze River, which are the most ecologically fragile mountainous area in China as well as one of the areas in China with most notable LUCC, have been on the Chinese Government's list of priority areas for ecological restoration. This paper is to reveal the trend of LUCC and the ecological degradation arising from it, and to provide a basis for the future sustainable use of land resources in the region based on a detailed analysis of Yiliang County. Based on the county's land use/cover maps in 1960, 1980 and 2000 drawn with the aid of aerial photograph interpretation, field investigation and GIS based spatial-temporal data analysis, LUCC during 1960~2000 period and the ecological degradation arising from it were analyzed. Using the Markv model, the paper brings out a forecast of what the county's LUCC would be like if the county's current land use continues, as well as the reasons and countermeasures for restoring degraded ecosystems.

Ecological security pattern-based simulation for land use structure change:a case study in Ezhou City,China

The ecological environment quality is an important constraint and an optimization objective for land resource allocation.Integrating ecological service value(ESV)accounting and ecological security pattern(ESP)delineation,and combining with the land use structure of 2004/2010/2016 in Ezhou City,this research laid out the urban ESP based on ESV with Net Primary Productivity(NPP),and made it as the main influence factor to simulate land use structure in 2022.The results indicated that:1)The water body has the biggest contribution to ESV,while the construction land has the minimum;2)91 ecological corridors are extracted,of which 28 were important ecological corridors;there were 36 ecological nodes extracted,including 17 important nodes;3)According to ESV,Ezhou City was divided into four security zones.The area of ecological restoration zone was the largest,and human activity core zone area was the smallest;4)In the no ESP protection scenarios and ESP protection scenarios separately,the net increase area of construction land is from 868.5 hm^(2) to 52.74 hm^(2) in the ecological core protection area;the construction land in the human activity core area has been increased by 2342.31 hm^(2) in protected scene,766.23 hm^(2) more than that of the unprotected scene.The results show that the division of security zones promoted the relocation of construction land from ecological protection core zone to human activity core zone,which can protect the ecological environment effectively,and the ESP-based simulation can provide the decision-making reference to coordinate the relationship of regional land resource allocation and the ecological environment protection.

Evaluating the Ecological Security of Land Resources based on Multi-source Data in the Altay Region of China

As a material carrier contributing to human survival and social sustainable development,the ecological environment is declining in its integrity and overall health.With the rapid development of society and economy,it is currently very necessary to carry out ecological security evaluation research to provide scientific guidance and suggestions for the construction of ecological civilization and the harmonious co-existence between man and nature.Taking Altay region as the research area,this paper collected and integrated regional geological,geographical,cultural,socio-economic,and statistical data,as well as previous research results.Combined with DPSIR and EES framework model,the evaluation index system of land resource ecological security in Altay region was constructed by using the analytic hierarchy process,entropy method and linear weighted summation function method.Using this index system,the evaluation research work was carried out to determine the current state of the security situation and the major threats which should be addressed.(1)The overall ecological security situation of Altay region was relatively safe,while the local ecological security situation was relatively fragile.Among them,the areas with safe and safer ecological environment accounted for 38.72%,while the areas with critically safe status accounted for 30.83%,and the areas with a less safe and unsafe environment accounted for 30.45%.In terms of spatial characteristics,the areas with unsafe ecological environment were mainly distributed in the west and east of the study area,while the areas with good ecological environment were distributed in the north of the study area.(2)Large-scale mining activities,frequent geological disasters,large-scale reclamation and long-term cultivation of arable land,and long-term large-scale grazing activities resulting in the destruction of grassland and vegetation were the main factors leading to the prominent ecological security problems of land resources in the Altay region.Therefore,in the process of the continuous development of the urban economy,we should pay more attention to the harmony between man and nature,and also actively and effectively advocate and implement certain policies and measures,such as returning farmland to forest,returning grazing land to grassland and integrating the mining of mineral resources.

Spatiotemporal analysis of land use/cover changes in Nanchang area, China

Based on remote sensing and Geographic Information System techniques,multi-temporal Landsat data were used to monitor land use/cover changes(LUCC)in the Nanchang area during 1989–2010.Quantitative and spatiotemporal indicators derived from the transition matrix for overall changes,intensity analysis for inter-category transitions,and spatiotemporal analysis of intra-category variations were constructed to analyze the spatiotemporal LUCC evolution.The study results show that urban and industrial land rapidly and continually expanded.The spatial extent of rural settlements shrunk while their distribution density increased.Cultivated land showed a tendency of spatially continuous loss and fragmented distribution,whereas the spatial pattern of forest tended to concentrate.The extents of ponds and reservoirs remained stable,but spatial changes were obvious.Rivers and bottomlands decreased significantly and tended toward fragmentation.The overall LUCC pattern showed that construction land rapidly sprawled while cultivated land decreased substantially,indicating an acceler-ating stage of urbanization and industrialization.Although rigid land requirements for urbanization had to be satisfied,land development and consolidation across forests and water body areas,as well as adjustment of agricultural structure,laid the foundation for a transition toward intensive land use in the Nanchang area.

我国草原修复工程效益评价与区域差异分析

基于全国草原监测数据和相关调研数据,评估了我国草原修复工程生态效益及区域差异。采用对比分析方法,对66个工程县植被盖度、鲜草产量和土壤健康进行了定量评价。结果显示:退牧还草工程显著提高了植被盖度(比非工程区高13.66%)和鲜草产量(提升60.81%)。京津风沙源治理工程成功遏制了沙化,显著增加了植被盖度和草产量。西南岩溶地区草地治理工程在生态、经济和社会效益方面取得了显著进展。研究表明:草原修复工程有效恢复了生态功能,提升了区域生态安全,但需优化管理策略确保其可持续性。

三峡库区生态敏感区土地生态安全预警测度与时空演变——以重庆市万州区为例

以三峡库区生态敏感区典型区万州区为研究对象,基于压力-状态-响应(P-S-R)框架构建土地生态安全预警指标体系,运用熵值法进行土地生态安全预警分析,并通过空间统计学方法对研究区土地生态安全警度的空间分布特征、变异规律及空间关联格局进行研究分析,旨在为区域土地资源利用的规划、管理及其生态保护提供决策参考。结果表明:(1)研究区2000-2014年土地生态安全警度呈连续上升趋势,土地生态安全警度较高区域由万州区中心城区不断向四周扩散,但2000-2009年期间研究区土地生态安全警度提升幅度比2009-2014年期间更为明显,2000-2009年期间是区域土地生态安全警度变化的关键时段。(2)研究区2000-2014年C_0/(C_0+C)呈不断上升趋势,表明非结构性因素对区域土地生态安全警度的影响程度在不断加大,这与研究区14年来经济高速发展、人类对土地资源利用强度加剧以及区域自然灾害频发的实际情况相符。(3)研究区2000年、2009年、2014年全局Moran's I值分别为0.7823、0.7772、0.775,表明土地生态安全预警指数在空间上存在较强的正相关关系,区域土地生态安全警度在空间上具有较强聚集性。(4)研究区"高-高"、"低-低"值区均呈现出2000-2009年范围逐渐增加,而2009-2014年范围逐渐缩小的趋势;且"高-高"值区主要集中分布在中心城区及其邻近区域,"低-低"值区则主要集中分布在研究区西北部和东南部等土地利用程度相对较弱、植被覆盖相对较好地区;中心城区周边的"低-高"值区将是城市发展中优先被占用的区域,在未来的土地利用中,尤其需加强对区域"低-高"值区的重点保护。

不同政策情景下荒漠化地区土地耕作适宜性评价

针对目前耕地适宜性评价中存在指标缺乏表达农民意愿及生态限制性因子的缺陷,应用基于生态限制性因子指标体系开展了中国荒漠化地区土地耕作适宜性评价。结果表明:在粮食安全政策导向情景下,荒漠化地区土地耕作适宜性较高的地区集中分布在亚湿润干旱区及半干旱区的局部地区,占地37×104km2;在生态环境政策导向下,荒漠化地区土地耕作适宜性较高的地区集中分布在内蒙古南部、西藏南部、新疆北部的局部地区,占地约26.9×104km2;由于政策导向的不同,宜耕减少地区主要集中于内蒙古东部和西藏南部的局部地区。该研究为大空间尺度土地耕作适宜性评价及多指标、尤其是生态限制指标的实用及不同情景的设置进行了积极的探索。

佛山市高明区生态安全格局和建设用地扩展预案

城市生态环境问题已上升到生态安全的层面。以人类生存安全和理想人居环境为目标,基于空间数据和统计资料,利用景观安全格局原理和地理信息系统空间分析方法,构建了包含基本保障格局-缓冲格局-最优格局3个级别的水安全格局、地质灾害安全格局、大气安全格局、生物保护安全格局和农田安全格局,叠加得到高明区综合生态安全格局,在此基础上提出了高明区建设用地扩展最优方案和生态功能分区。结果显示,并非生态安全格局水平越高,城乡发展模式越优,缓冲生态安全格局下的高明区建设用地扩展模式,最可能实现生态安全保护与城镇扩展的和谐发展。综合生态安全格局明确了区域的生态环境敏感区和生态服务功能重要区,为区域生态功能分区提供了新的思路。

黄土丘陵区土地资源生态安全及其动态评价

土地资源生态安全研究是当前区域可持续发展研究的前沿课题，科学评价区域土地资源生态安全状态及变化，是土地利用科学决策及土地利用模式优化的基础和依据。本文界定了土地资源生态安全的概念，针对黄土丘陵区土地资源特点及面临的主要生态问题，基于P．S．R概念模型运用层次分析法建立了黄土丘陵区土地资源生态安全评价指标体系，并对指标安全闽值的确定进行了初步探讨。鉴于土地资源生态安全的动态特性，提出了基于状态评价模型和趋势分析模型相结合的区域土地资源生态安全动态评价方法，弥补了传统静态评价方法的不足，以地处宁南黄土丘陵区的彭阳县为例，进行了实证研究，对彭阳县1986年～2004年土地资源生态安全状态及变化趋势进行了评价和分析，结果表明近20年来该区域土地资源生态安全变化趋势趋于改善，但目前安全状态仍处于较不安全等级，评价结果能较为全面客观地反映该区域土地资源生态安全状况。

区域生态补偿与土地生态安全

研究目的:划定中国土地生态补偿分区方案,并提出相关的政策建议。研究方法:格局空间统计分析与生态地理区划。研究结果:中国土地生态安全表现为下降趋势,西部地区为高生态安全区,东部地区为低生态安全区,是生态服务功能空间传递的受益区,可将中国划分为生态补偿受体区(主要分布于西部)和生态补偿主体区(主要分布于东部)两个一级大区。研究结论:设立全国性的土地生态补偿专门机构,构建土地生态补偿的法律体系,建立科学高效的土地生态补偿监管体系,完善土地生态补偿的政策导引。

江苏沿海地区耕地景观生态安全格局变化与驱动机制

沿海地区是土地利用变化剧烈区,同时也是生态系统敏感脆弱区。以江苏省沿海为研究区,基于景观生态安全理论,结合遥感技术与空间分析技术,从景观生态安全角度测算沿海19个县耕地景观生态安全指数,在此基础上,重点讨论1995—2005年江苏沿海地区耕地景观生态安全格局变化特征与驱动机制。研究结果显示:江苏沿海地区15a来耕地景观安全格局变化显著,Ⅰ级区范围呈扩大趋势,Ⅱ级区格局变化较为分散,Ⅲ级区的范围逐渐缩小,呈现由南部地区向中部地区减少,由内陆向沿海推进的格局变化特征;回归模型显示,县级层次耕地景观生态安全主要驱动力为土地整理项目数量、国民经济总产值和人口密度,其回归系数分别为0.253、-0.224和-0.176。

生态安全条件下亚洲沙区土地利用结构研究

基于数字地图与遥感影像资料,通过分析土地利用格局与沙尘传输关系,研究了生态安全条件下土地利用结构优化的模式、方法与技术。研究表明:①亚洲生态安全条件下的土地利用/覆盖宏观三圈格局为:内圈以自然保护为主的沙漠地带;中圈以建设人工草地为主,辅以大面积自然恢复的草原地带;外圈以农、林、牧复合为主的交错地带。中国处在宏观三圈格局的中东部,北方沙区是影响东亚沙尘暴的重要源区。②中国半干旱沙区土地利用呈现微观三圈模式,基于RS数据,依据“大面积搞生态,小面积搞生产”的原则进行的土地利用结构优化,提出了外圈沙丘地恢复天然草地生态用地———中圈草原地带大面积搞生态—小面积搞牧业生产———内圈甸子地高效农业生产用地的生态—生产范式。③典型区科尔沁沙地土地利用结构优化的成套技术,可为类似地区政府土地利用决策与生态补偿机制提供支持。

鄱阳湖区土地生态安全评价

在对鄱阳湖区土地生态安全特征研究的基础上,建立了土地生态安全评价模型。并对湖区11个县的土地生态安全进行评价,划定安全等级,分析了影响区域土地生态安全的主要胁迫因子,为该区土地生态安全建设提供借鉴和指导。

中原经济区核心区土地资源生态安全评价

采用熵权赋权法构建了中原经济区核心区土地资源生态安全评价指标体系,综合评价了2002—2011年中原经济区核心区土地资源生态安全动态。结果表明,2004年中原经济区核心区土地生态安全指数增加到最大值0.675 5,土地安全等级为"Ⅱ"级,较安全,2011年土地安全指数下降到0.310 6,土地安全等级退化为"Ⅳ"级,较不安全。2002—2011年,郑州市、许昌市和焦作市的土地资源生态安全动态呈"单峰"型,开封市和新乡市的土地资源生态安全动态呈"双峰"型,洛阳市的土地资源生态安全动态呈"U"型。中原经济区核心区土地资源生态安全的空间变化呈现出"以郑州为中心,南北恶化、东西好转"的特点。

长株潭地区耕地生态安全评价研究

耕地生态安全关系到可持续发展和粮食安全。以长株潭地区耕地为研究对象,基于改进的PSR模型构建耕地生态安全评价指标体系,运用组合赋权法确定指标权重,并对长株潭地区耕地生态安全进行定量分析和评价。结果表明,在2000—2012年,研究区域耕地生态安全综合指数从37.59增加到55.82,生态安全整体水平呈波动上升趋势。其中,压力指数由23.37下降到4.14,年均减少率为6.86%;状态指数从10.00增加到33.55,年均增长率为19.63%;响应指数从4.22增加到18.12,年均增长率为27.45%。影响耕地生态安全的主要因素是耕地环境质量指数、第一产业产值占GDP比重、单位耕地农业机械化水平、单位耕地粮食产量、环保投资额占GDP比重和当年造林面积。