Patterns of biodiversity and habitat sensitivity in agricultural landscapes

Design of landscape is the process of the arrangement of spatial features with the objective of sustaining ecosystem services, and maintaining ecological functionality to meet societal needs. Along a gradient of cultivation intensity, the functional quality of agricultural landscape was explored and the relationships between landscape metrics and functional quality were analyzed, in order to make effective recommendations for landscape design aimed at sustainable land use schemes. The functional quality of landscape was calculated using the InVest model for 20 farm landscapes (North-Eastern Italy) where biodiversity (plant taxa) and sensitivity to disturbance (hemeroby) were used as model inputs. Results highlighted the importance of specific habitat types such as meadows and woodlands rather than other habitats for improving the biodiversity of agricultural landscapes. A high proportion of these habitats enhanced the functional quality of the landscape when the habitats were organized in large and not isolated patches in heterogeneous landscapes.     

Landscape as a predictor of wetland condition: an evaluation of the Landscape Development Index (LDI) with a large reference wetland dataset from Ohio

RecentAbstract. Recent approaches to wetland assessment have advocated a multilevel approach which incorporates assessments based on landscape (remote sensing) data, on-site but “rapid” methods, and intensive methods where quantitative data is collected. Brown and Vivas (2004) recently pro- posed an assessment method that uses remote sensing information (Landscape Development Index or LDI) and propose that it may also be usable as a quantified human disturbance gradient. The LDI was evaluated using a large reference wetland data set from Ohio using land use percentages within a 1 km radius circle of the wetlands. The LDI had interpretable and significant relationships with another human disturbance gradient (the Ohio Rapid Assessment Method for Wetlands or ORAM) and with most metrics and scores from the Vegetation Index of Biotic Integrity (VIBI) developed for use in the State of Ohio. Metrics from emergent wetlands had the most significant correlations with the LDI (10 of 10 metrics), followed by forested wetlands (8 of 10 metrics) and shrub wetlands (4 of 10). Poor correlation for VIBI scores and metrics of shrub wetlands was due to differences in attainable LDI scores based on ecoregion and natural buffers shielding the wetland from otherwise intensive land uses. The ORAM and VIBI were developed for use in wetlands in Ohio completely independent of the LDI. It is an important test of the LDI concept that so many interpretable and significant relationships occurred between the VIBI scores, VIBI metric values, and the ORAM scores. For the purposes of VIBI development, the LDI is an independent, quantified disturbance gradient that has provided an additional test of the VIBI. Given its theoretical underpinnings and the fact that it uses quantified land use percentages, the LDI has many advantages over more qualita- tive human disturbance gradients. Using land use percentages from increasingly smaller distances from the wetland edge (100-200 m) may improve the resolution of the LDI to detect on-site dis-turbances to a wetland which degrade its ecological condition. The LDI should be evaluated with other large reference data sets in other regions to evaluate its validity and usefulness as an assessment tool.     

新疆艾比湖流域平原区景观植被属性特征研究

在对新疆艾比湖流域平原区进行景观生态分类的基础上,利用“3S”技术叠置研究区草地资源类型图与景观类型图,对研究区景观植被属性特征进行分析。结果表明,研究区主要为荒漠、草原和草甸,共有33个植物群落类型,小蓬荒漠、梭梭荒漠、刚毛柽柳荒漠等各类荒漠面积合计约占研究区总面积的74．10％,芦苇草甸、含胡杨的芦苇草甸及矮嵩草草甸等各类草甸及草原面积也较大,占研究区总面积的18．34％。     

喀斯特石漠化生态恢复中的生物多样性研究进展

喀斯特生态系统是陆地生态系统的重要组成部分,生态恢复是喀斯特石漠化治理的核心任务,研究石漠化生态恢复机理、优化生态系统功能、提升生态系统服务和实现喀斯特生态环境可持续发展是当前石漠化治理的重要议题.通过对遗传、物种、生态系统和景观四个层次生物多样性退化与恢复的关注,生物多样性作为重要的生态系统特征及表征指标,在石漠化生...     

近30年来鄱阳湖环湖区土地利用与景观格局变化研究

以1988—2018年7期Landsat遥感卫星影像为数据源,采用土地利用转移矩阵、景观格局指数等方法探究了鄱阳湖环湖区近30年来土地利用与景观格局变化特征.结果表明：(1)近30年来鄱阳湖环湖区建设用地和林地面积显著增加,耕地、草地、水域和未利用地面积减少.(2)建设用地的转入类型以耕地为主,30年间共侵占耕地面积1243.66 km²,占建设用地面积增加量的71.19%.林地的转入类型主要为耕地和草地,其中,耕地转入占比56.95%.耕地的转出类型以建设用地、草地和林地为主,且1999年以后随着城镇化的发展耕地主要转向建设用地.(3)近30年来鄱阳湖环湖区景观总体破碎程度逐渐增大,景观斑块个数共增加63492个,增幅为11.68%.景观连通性降低,各类型土地呈均衡化趋势分布,景观异质性增加.研究结果可为推动鄱阳湖环湖区土地资源保护、生态环境保护和经济协同发展提供参考依据.     

基于本底格局的鸭绿江口滨海湿地景观破碎化评价

在3S技术支持下构建了鸭绿江口滨海湿地景观本底格局,并以本底格局为参照,分别对1989年和2005年鸭绿江口滨海湿地景观破碎化过程进行了监测评价.结果表明:湿地本底格局可作为强度开发环境下湿地景观格局破碎化评价的参照依据.与本底格局相比,鸭绿江口湿地景观格局呈持续破碎化趋势,1989年和2005年湿地景观整体自然度分别为89.373%和86.691%.在不同自然湿地景观类型中,芦苇沼泽、滩涂和潮沟面积萎缩幅度较大,2005年其自然度分别为69.94%、71.49%和78.42%;各湿地类型的斑块密度都出现了不同程度的增大,其中芦苇沼泽和滩涂增大最明显,2005年斑块相对密度分别达18.507和6.879;滩涂斑块形状趋于复杂,2005年斑块相对形状指数为1.085,其他湿地类型斑块形状则持续简化;各时期不同自然湿地类型斑块聚集度指数均较高,反映出鸭绿江口各湿地类型多呈聚集分布的空间格局.     

景观生态学方法在规划环境影响评价中的应用 ——以大连森林公园东区规划环境影响评价为例

在综合考虑各种社会经济影响因素的基础上,从景观格局、景观功能、景观受胁迫性等3方面构建评价指标体系,并据此开展规划实施的景观生态影响综合评价.利用计算机模型模拟各种规划替代方案的景观格局动态,并通过分析景观格局指数的变化实现对规划替代方案的比选,建立起规划环评中景观生态学方法应用的技术框架,进而应用于大连森林公园东区建设规划环境影响评价.研究结果表明,规划的实施有利于区域景观格局和功能的改善,但会导致人类对景观干扰和胁迫加重.采用以旅游经济为主导型方案(替代方案1),景观破碎化趋势明显;以生态优先主导型方案(替代方案2),景观向整合集约化趋势发展.     

关于中国西部“山川秀美”再造的思考——兼论西部生态安全建设中的防灾减灾

再造一个“山川秀美”的大西北 ,展现出一幅理想的人与自然依存的场景。笔者为此给出独特的思考和科学的见解 :要实现这一目标 ,必须研讨“山川秀美”的科学内涵 ,以恢复大西北自然生态安全环境为基础 ,以防灾减灾 ,保护人与自然为手段 ,依靠科技进步 ,坚持可持续发展战略 ,从长远利益并结合地区实际 ,才能真正实现人与自然和谐共存的“山川秀美”     

Statistical detection of multiscale landscape patterns

Detection of discontinuities in landscape patterns is a crucial problem both in ecology and in environmental sciences since they may indicate substantial scale changes in generating and maintaining processes of landscape patches. This paper presents a statistical procedure for detecting distinct scales of pattern for irregular patch mosaics using fractal analysis. The method suggested is based on a piecewise regression model given by fitting different regression lines to different ranges of patches ordered according to patch size (area). Proper shift-points, where discontinuities occur, are then identified by means of an iterative procedure. Further statistical tests are applied in order to verify the statistical significance of the best models selected. Compared to the method proposed by Krummel et al. (1987), the procedure described here is not influenced by subjective choices of initial parameters. The procedure was applied to landscape pattern analysis of irregular patch mosaics (CORINE biotopes) of a watershed within the Map of the Italian Nature Project. Results for three different CORINE patch types are herein presented revealing different scaling properties with special pattern organizations linked to ecological traits of vegetation communities and human disturbance.