城市用地抗震适宜性分区研究

针对我国现行《城市抗震防灾规划标准》有关城市用地抗震适宜性评价的规定,建立了城市用地抗震适宜性评价指标体系;采用层次分析法确定了各评价指标的权重值;根据抗震适宜性综合指数的概念,得到了研究区实测钻孔资料的抗震适宜性综合指数,在GIS技术的支持下,生成了城市用地抗震适宜性综合指数等值线图,并据此进行了城市用地抗震适宜性分区;可为城市的总体规划提供依据。     

Breeding skylarks (Alauda arvensis) on organic and conventional arable farms in The Netherlands

The aim of this study was to analyse the effects of differences in cropping pattern between organic and conventional arable farms on the breeding activity of skylarks and to assess the effects of arable crop management on skylark nest survival. Skylark nest density was seven times higher on organic farms than on conventional farms (0.63 vs. 0.09 nest per 10 ha). Skylarks showed a strong preference for spring cereals, lucerne and grass leys, all of which were mainly or exclusively grown on organic farms. On organic farms nests were initiated during the entire breeding season, but on conventional farms no nesting activity was found during the peak of the season (early May to early June). On organic farms 27% of all nests was successful. Increasing the availability of suitable breeding habitat during the peak of the breeding season on conventional farms might provide one means of enhancing breeding skylark populations. On organic farms, crop management should focus on reducing nest loss due to farming operations.     

北京市畜禽粪便土地利用适宜性分析

以北京市为研究区域,基于GIS下采用权重线性加和模型(WLC),综合自然、环境、社会和经济等多因子.对北京市畜禽粪便土地利用的适宜性进行了定量分析.结果表明,北京市10个郊区县适合施用畜禽粪便的耕地面积为1605.3 km2,占耕地总面积的35.3%,主要分布在北京市的南部、东南部和中部地区.聚类分析将全市郊区划分为东南部、北部、西南部和中部4个区域.东南部和中部远郊平原区比较适合发展畜禽养殖业,目前的养殖量与最大承载量之间尚存在一定空间;但是由于城镇化的加快,可施用粪便的农田与居民区的安全距离成为影响粪便施用的主要因素,需要结合有效的管理措施以避免畜禽粪便土地利用的污染风险.北部和西南部远郊低山丘陵区应适度控制畜禽养殖业的发展,由于北部区县(延庆、怀柔、密云和平谷)河流密集,并分布有北京市的主要地表水源,故与水体的安全距离对该地区的耕地施用粪便有重要影响;应控制和减少土壤沙化及水土流失,同时建立滨岸缓冲带来控制畜禽粪便土地利用对水体的进一步污染,以达到经济发展和环境保护的双重目的.     

Patterns of plant trait-environment relationships along a forest succession chronosequence

Land-use change due to socioeconomic factors leads to the abandonment of traditional intensive coppice management in large areas of the mountainous landscapes of the Apennines (Italy). In this study we explored the multivariate relationship between plant species traits, stage of forest succession and environmental gradients. We focused on community-level patterns in plant traits of the vegetation of beech forest understory along the regeneration chronosequence initiated after cessation of coppicing. We hypothesized that the correlations between the traits and environmental factors should increase with succession age due to the decreasing role of chance.Landscape-level heterogeneity, i.e. changing elevation, slope, exposition, bedrock and forest stand age was assessed using a stratified random sampling design. Sixty sites were sampled for stand structure and species composition. We focused on 14 plant traits related to persistence, growth and dispersal. The recently developed data-analytical method, Model-Based Recursive Partitioning, was used to disentangle the relationships between patterns of plant traits and environmental gradients.About half (seven) of the studied plant traits showed significant correlations with succession stand age, elevation, inclination, heat index and bedrock. Contrary to the low number of trait-environment correlations in early succession, eight traits showed significant relationships with one or more abiotic factors in older stages of the post-coppice development. Stand age had the highest independent explanatory power, explaining 40% of variance of SLA, more than 17% of variance of short-distance seed dispersal and more than 15% of variance of both long-term connection and extensive perennial root. Among the other abiotic factors, elevation explained 27% of variance of SLA, inclination explained 6-8% of variance of long-term connection, extensive perennial root, thickening and large bud bank.The observed trait-environmental relationship is assumed to be driven by various environmental factors operating at various levels of complexity. While forest succession in relatively homogeneous landscapes might be driven mainly by environmental factors related to forest succession itself and associated abiotic changes (such as changes in light and soil moisture patterns), in heterogeneous landscapes the succession pathways may be structured by landscape-level environmental factors such as inclination. However, in the present study, forest stand age had the highest explanatory power for most of the investigated traits, supporting the assumption of the overall strong impact of succession-driven environmental factors in trait-environment relationships.     

Consequences of correlations between habitat modifications and negative impact of climate change for regional species survival

While several empirical and theoretical studies have clearly shown the negative effects of climate or landscape changes on population and species survival only few of them addressed combined and correlated consequences of these key environmental drivers. This also includes positive landscape changes such as active habitat management and restoration to buffer the negative effects of deteriorating climatic conditions. In this study, we apply a conceptual spatial modelling approach based on functional types to explore the effects of both positive and negative correlations between changes in habitat and climate conditions on the survival of spatially structured populations. We test the effect of different climate and landscape change scenarios on four different functional types that represent a broad spectrum of species characterised by their landscape level carrying capacity, the local population turnover rates at the patch level (K-strategies vs. r-strategies) and dispersal characterstics. As expected, simulation results show that correlated landscape and climatic changes can accelerate (in case of habitat loss or degradation) or slow down (in case of habitat gain or improvement) regional species extinction. However, the strength of the combined changes depends on local turnover at the patch level, the overall landscape capacity of the species, and its specific dispersal characteristics. Under all scenarios of correlated changes in habitat and climate conditions we found the highest sensitivity for functional types representing species with a low landscape capacity but a high population growth rate and a strong density regulation causing a high turnover at the local patch level.The relative importance of habitat loss or habitat degradation, in combination with climate deterioration, differed among the functional types. However, an increase in regional capacity revealed a similar response pattern: For all types, habitat improvement led to higher survival times than habitat gain, i.e. the establishment of new habitat patches. This suggests that improving local habitat quality at a regional scale is a more promising conservation strategy under climate change than implementing new habitat patches. This conceptual modelling study provides a general framework to better understand and support the management of populations prone to complex environmental changes.     

苏州地区地下水资源城市应急利用适宜性研究

随着太湖水体富营养化程度的不断加剧,建立安全、稳定、可靠的应急备用水源日益重要。利用2005~2009年苏州地区地下水水质连续监测和补充监测资料,对第Ⅱ承压含水层进行了应急利用(生活饮用和工业利用)的水质适宜性和安全性评价分析。研究结果表明:第Ⅱ承含水层主要水化学类型为Na-HCO3、Ca-HCO3和Na-CaHCO3型,水质总体稳定,年际差异很小;地下水水质指数(WQI)均值较低(位于49.98~68.75之间),地下水没有受到有机物污染,可作为应急利用水源;WQI的水质指标贡献率表明,As、Fe、pH和Mn指标的贡献率最大,局部区域As、Fe、Mn及氨氮和亚硝酸盐含量较高,应急利用时应进行处理。朗格里尔饱和指数(LSI)和拉森比(LnR)评价结果表明,该水源易结垢,具有轻微腐蚀倾向,作为工业备用水源时应进行适当的处理。为苏州地区地下水应急水源建设和安全利用提供了科学依据和参考。     

我国农地规模经营适宜性评价及分类研究

农地规模经营是农业现代化发展的必经之路,是解决当前“三农”问题的重要途径之一.根据影响农地规模经营的因素建立了农地规模经营适宜性评价指标体系,运用熵值法对我国31个省级行政区的农地规模经营适宜性进行了分析,将我国各地区按照不同的农地规模经营发展条件分为五类,并以评价结果为依据确定各类别的发展条件优劣,为探索农地规模经营发展路径、制定差别化的发展政策等研究和应用提供理论参考.     

干旱内陆河流域人居环境适宜性评价——以石羊河流域为例

论文以干旱区内陆河石羊河流域为研究区,选取坡度、 坡向、 地形起伏度、 植被指数、 水文、 气候、 交通等因子作为评价指标,建立了人居环境指数(HEI),利用GIS的叠置分析、 缓冲区分析、 密度分析等空间分析技术对石羊河流域人居环境适宜性进行了定量综合评价分析。评价结果表明,石羊河流域人居环境指数介于17.13~84.32之间,整体分布格局为:从西南方向到东北方向适宜性依次降低,适宜、 较适宜居住区主要分布在中游和中下游地区,不适宜人类居住区占研究区面积的比例很大。石羊河流域人居环境适宜区主要以带状和斑块状分布在石羊河各支流周围,其他区域只有零星分布,与流域内居民点分布的空间格局相吻合。石羊河流域人居环境状况与人口密度呈对数关系,确定系数达到0.851 2,与经济发展水平呈现较明显的正相关性,人居环境评价值与单位面积GDP确定系数达到0.845 4,与道路网密度关系不显著,受道路制约程度较小。一些居民点分布在人居环境恶劣区域,一些村镇分布在靠近沙漠区域内,地形复杂,气候多变,水资源短缺,经济发展滞后,结合新农村建设规划和当地土地利用规划,这部分村落需要异地搬迁以便改善人居环境状况。     

长江三角洲旅游景区布局适宜性评价

论文从影响因素出发,以长江三角洲为例,构建旅游景区布局适宜性评价体系,从城镇依托度、交通优势度、社会支撑度和现有景区影响度四个方面来综合评价长江三角洲旅游景区布局适宜性。分析结果表明,城镇依托度呈现出以市级城市为中心的圈层分布结构;交通优势度呈现出以机场为中心的圈层分布结构;社会支撑分值总体上呈现出以太湖为核心的圈层结构;现有景区影响度数值较高的地区主要分布在长江以北地区,并零星分布在长江南岸,总体上呈现内低外高的格局。高适宜性区域主要分布在两大片区,一个是长江两岸地区,另一个是杭州湾两岸地区。低适宜性区域主要分布在长江三角洲边缘地区,特别是西南和南部边缘地区,以及舟山群岛地区。     

Application of analytical hierarchy process and geographic information systems in land-use suitability evaluation: a case study of Dümrek village (Çanakkale,Turkey)

This study used both analytical hierarchy process (AHP) and geographic information systems (GIS) to make a land-use suitability analysis for the village of Dümrek, NW Turkey. Primarily, alternative land uses for agriculture, meadow–pasture and forest were determined along with criteria for these alternatives and a hierarchical structure was produced and used to determine the weights of the criteria. Spatial data were identified by means of GIS and calculations were made using the suitability values specified and weights obtained from AHP. Suitability maps were then produced for the above land use alternatives. Subsequently, a synthesized suitability map was formed from these maps. According to the weights specified by AHP, the order of land use preferences among the alternatives for rural development of Dümrek was agriculture, forest and meadow. The synthesized suitability map showed that the areas allocated for forest and agriculture were close to the present ratios of use; however, meadow land, which does not exist at present, should be allocated as a land use to constitute 12.5% of the study area. Achieving sustainability in land use is possible by planners and administrators considering results obtained from land suitability mapping studies at the stage of allocating land uses. The method applied in this research is considered useful when taking policy decisions covering the evaluation of rural land use, particularly for subunits of the state administration.