Changes In Spatial Structure Research Articles

华北农牧交错带农田-草地景观镶嵌体土壤水分空间异质性

PDF HTML阅读 XML下载 导出引用 引用提醒 华北农牧交错带农田-草地景观镶嵌体土壤水分空间异质性 DOI: 10.5846/stxb201306091519 作者: 作者单位: 宁夏大学 农学院,宁夏大学 农学院,中国农业大学 动物科技学院 北京,宁夏大学 农学院,宁夏大学 农学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然基金资助项目(31060325) Spatial heterogeneity of soil moisture across a cropland-grassland mosaic：a case study for agro-pastural transition in north of China Author: Affiliation: NingXia University,,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为揭示草地景观破碎化过程中产生的农田-草地镶嵌体内部土壤水分空间异质性、分布格局以及生态界面特征,本研究利用经典统计与地统计学方法对华北农牧交错带农田-草地镶嵌体不同采样粒度(0.5 m×0.5 m,1 m×1 m,2 m×2 m)土壤水分空间异质性进行分析。结果表明:农田-草地镶嵌体内部土壤水分含量差异显著表现为农田>农田-草地边界>草地 (P < 0.05);土壤水分变异系数(CV Coefficent of variation)差异显著表现为农田-草地边界>草地>农田(P < 0.05),均属中等程度变异。在农田-草地镶嵌体尺度下,农田-草地边界土壤水分在3个采样粒度下均拟合为球状模型,空间异质性大小(MSH Magnitude of spatial heterogeneity)分别为0.814、0.763和0.883,变程为15.44、27.24和19.09 m,属强空间自相关;草地土壤水分空间异质性在3个采样粒度下拟合呈指数和球状模型,空间异质性大小分别为0.537、0.837和0.650,变程分别为6.009、12.74和30.99 m,属中到强空间自相关;农田土壤水分在采样粒度2 m×2 m下拟合成球状模型,空间异质性大小为0.706,变程27.28m,属中等空间自相关,而在较小采样粒度下均为纯金块效应(Nugget)呈完全随机分布,即不同采样粒度(0.5 m×0.5 m,1 m×1 m,2 m×2 m)的农田、农田-草地边界、草地的土壤水分空间异质性大小存在显著差异且表现为农田-草地边界>草地>农田(P < 0.05),同时每种类型不同采样粒度间的空间异质性大小存在差异但无线性关系(P > 0.05);农田-草地镶嵌体内部的农田-草地边界土壤水分分布格局异质程度高,呈明显斑块状,而农田内部土壤水分较草地更加破碎匀质化,同时土壤水分在农田-草地边界处表现为伴有突然升高随即降低剧烈变化的界面效应。 Abstract:As a direct consequence of greater landscape fragmentation worldwide, it is becoming increasingly common for agricultural landscapes to be dissected by boundaries between crop types. However, our understanding of processes associated with these boundaries remains comparatively undeveloped. Cropland-grassland mosaics resulting from intensification of farming activity on extensive grassland are now common in north of China. These land use changes not only influence the original ecosystem processes but also generate new ecological processes that impact on the regional environment at a larger scale. Recently the topic of spatial heterogeneity of soil moisture has received more attention from ecologists because it plays an important role in the hydrological cycle through effects on the interaction between land and atmosphere, thus climate and plant growth in different ecological scales. Despite this emerging focus few studies have examined the spatial heterogeneity of soil moisture in cropland-grassland mosaics in north of China. Here we report data investigating the spatial pattern for soil moisture variation in cropland (C), the cropland-grassland boundary (B) and grassland (G) of a cropland-grassland mosaic. The scale of heterogeneity for soil moisture was assessed by evaluating sampling units of differing sizes (0.5 m×0.5 m, 1 m×1 m, 2 m×2 m) using classical statistical and geostatistical methodologies. Soil water content of C was significantly higher than that of G (P < 0.05). Soil water content of B was intermediate between C and G and differed significantly from both C and G (P < 0.05). The B zone displayed a higher coefficient of variation (CV) for soil moisture than the adjacent systems (P < 0.05), The geostatistical analysis determined that values of the magnitude of spatial heterogeneity (MSH) for soil moisture for B were 0.814, 0.763 and 0.883, respectively, in the three sampling grain sizes (0.5 m×0.5 m, 1 m×1 m, 2 m×2 m). There was also a strong autocorrelation with the ranges A0 15.44, 27.24 and 19.09 m, respectively. The MSH values of soil moisture for G were 0.537, 0.837 and 0.650, and there was a moderate to strong autocorrelation with the ranges A0 6.009, 12.74 and 30.99 m, respectively, in the three different sampling grain sizes. The MSH of soil moisture for C was 0.706, which had a moderate autocorrelation with range 27.28 m in grain size 2 m×2 m, whereas there were nugget effects at the other finer sampling grain sizes. The MSH of the cropland-grassland mosaic displayed a nonlinear relationship across different sampling scales in the field. We found soil moisture for B displayed the highest spatial heterogeneity (i.e. significant patchiness), whereas the soil moisture for C was more homogeneous in comparison with soils under grassland. With respect to the characteristics of the B transition zone, there was an abrupt change of increase then rapidly decreases for soil moisture from cropland to grassland in the cropland-grassland mosaic. The data therefore support the ‘ecological boundary effects’ hypothesis that the ecological boundary is more heterogeneous than that of the adjacent systems and also show that abrupt ecological boundary effects occur. Our results suggest that the historical shift from perennial herb to monocrop culture in grasslands ecosystem led to changes in the small-scale spatial structure of soil moisture and related processes. These changes in land utilization may therefore alter ecosystem function and further impact the regional climate. 参考文献 相似文献 引证文献

Modeled Surface Observations for Spatial Analysis of Landscape Dynamics

Landscape dynamics is a geoecological characteristic that defines changes in a landscape spatial structure and function during an established time scale. In this kind of analysis, geoprocessing is an essential tool, because it combines several technologies that help in this work. However, the majority of landscape dynamic investigations do not consider the dimensionality of the data and the information to be used, which is projected not measured from modeled (real) surface observations, and presents underestimated results, mainly in irregular relief landscapes. Considering that, this paper intends to assess the difference between observations on modeled and planimetric surfaces on the interpretation of landscape dynamics. The study was conducted in the massif of Tijuca, Rio de Janeiro (Brazil) using land use and soil cover maps of different times and a digital elevation models (DEM) generated based on a triangular irregular. The results show an increase of dynamic areas values when observations were carried out on modeled surface, as well as the deforestation rate (17.57% or 0.13 km2/year). This survey showed higher values in comparison with observations on planimetric surface, characterizing more realistic interpretations of how the structural elements and analyses made from these are structured in the landscape.

Atomic-force microscopy in studyng hard tissues of orofacial area

Aim. To study the use of atomic-force microscopy for morphological diagnosis of a bone tissue and hard tooth tissue pathology. Methods. Dental occlusion, enamel crowns and bony tooth sockets shape and size, as well as embrasures’ size and their depth, and crown height were estimated by the means of atomic-force microscopy. 30 teeth and bony fragments removed due to blunt maxillofacial trauma with signs of connective tissue hypermobility and 27 removed teeth and bony fragments from the control group were analyzed. Results. Abnormal collagen structure in hypermobility syndrome was associated with the increase of inter-fiber space to 98 nm and decrease of mineral matrix content in the bone. Enamel crowns shape and size alterations [(5.5±0.3)×(5.4±0.1) μm] as well as inter-crown space increase to 1.5±0.1 μm were found out. At the bone tissue analysis, the main distinctive feature between the control group and the patients with hypermobility syndrome was the presence of cystic lesions in the hypermobility syndrome group, accompanied by change of bone mineral structures disposition, trabeculae formation and changes of bone mineral density. In patients with hypermobility syndrome low mineralization of hydroxyapatite crystal structure, changes in spatial crystal structure as well as organic matrix disposition, all leading to enamel structure malformation due to change of interrelation between enamel organic and mineral components which is not typical for that certain period of teeth ontogenesis were found at enamel examination. Thus, in patients with connective tissue hypermobility signs of bone and enamel mineralization and structure change were found. Conclusion. The use of atomic-force microscopy allows to study the native cell cultures, including bone and hard tooth tissues, that can be used as a basis to diagnose connective tissue hypermobility as well as for identification of personality.

A Study on the Capital Area's Urban Type Analysis and Real Estate Characteristics

In recent times, multi-centralization and decentralization as well as large Capital area and suburbanization in the spatial structure of capital area. With rapid growth, urbanization and industrialization are unsystematic, and growth inequality between regions caused negative effects such as discordant centralization and decentralization, fluctuating land value, and gap between living conditions. Accordingly, this study analyzed urban spatial indexes by the self-governed body in the capital area such as Seoul, Incheon, and Gyeonggi province for the analysis of the regional inequality phenomenon. We examined the characteristics of temporal and spatial changes in urban spatial structure in the capital area by utilizing the distribution pattern and density of city indexes such as population, employment, etc, and then drew the commonality of those factors through factor analysis. We evaluated the drawn results through the city standard index by each city, conducted factor score analysis, and identified the interaction between each factor and Housing Purchase Price Composite Indices index, housing rent price index(Housing Jeonse Price Composite Indices), land price fluctuation rate, diffusion ratio of house, and financial independence.

The Design, Experience and Justice of Mobility

The central argument of the ‘mobilities turn’, that sedentarist frameworks have dominated social sciences for a long time, which has limited our understanding of mobilities (e.g. Cresswell 2006, 2010; Hannam et al. 2006; Sheller & Urry 2006; Urry 2007) – also applies to the spatial disciplines, andhumangeography in particular. Ofcourse, themovementandtransport ofgoods and people have always been on the agenda of the spatial sciences. However, these mobilities have mostly been analysed from the position of fixed points. In mainstream transport research, mobility has typically been perceived as ‘merely’ a derived demand, warranting study only as a connector between desired activities. In line with this conceptualisation, movement between places is, either implicitly or explicitly, considered as friction and a loss of time that has to be limited. Equally so, the push-pull models of migration studies presented the mobile part as a static point-to-point movement without any further social meaning or transformative power. From the position of fixed points, mobilities have thus been perceived as ‘residual death time,’ ‘friction’ or ‘empty spaces’ (e.g. Cresswell 2006; Urry 2007). Scholars who engage themselves in the mobilities turn approach spatial interaction and mobility differently. First of all, mobility is seen as a process and a motor of change. Both places of origin and places of destination change through the movement of people, goods, money and information from one place to the other, and thus mobility is seen as a major factor in space- and place-making. This goes beyond the traditional geographical approach, which focuses primarily on changing spatial structures as a resultant of spatial interaction potentials. Second, these mobilities researchers explicitly explore how people, as well as other material and immaterial objects of exchange, change themselves through the process of relocation, something which has largely been ignored in the spatial disciplines, and mainstream transportation research in particular. While this new mobilities’ research is an interdisciplinary debate bringing together, among others, geographers, anthropologists, planners, political scientists and sociologists to re-think the role of mobility in different societies (Hannam et al. 2006, Urry 2007), authors strongly share these basic starting points. The emerging new mobilities literature, we argue, has the potential to substantially enrich mainstream transportation research. However, this requires transcending existing boundaries and bridging the divide between the world of ‘transport mobility’ – perceiving mobility a way to overcome the friction of distance and a functionalist force and (re)structuring the urban landscape – and the world of ‘practice mobility’ – approaching mobility as a transformative power opposing the fixity and boundedness of space and place (Massey 2005; Cresswell 2006; Sheller & Urry 2006). The differences are not only to be found in terms of disciplinary jargon and research topics, but also in terms of methodology and conceptual frameworks. To create a common ground for debate, we have identified three potential bridging concepts that may help evoke a border-crossing debate. These dimensions are: designs, experiences and justice. Before discussing the extent to which the different contributions in this special issue invoke these bridging concepts, we first articulate the ways we think they can bring both sides of the divide closer together.

A temporary decrease in mineral density in perinatal mouse long bones

Fetal and postnatal bone development in humans is traditionally viewed as a process characterized by progressively increasing mineral density. Yet, a temporary decrease in mineral density has been described in the long bones of infants in the immediate postnatal period. The mechanism that underlies this phenomenon, as well as its causes and consequences, remain unclear. Using daily μCT scans of murine femora and tibiae during perinatal development, we show that a temporary decrease in tissue mineral density (TMD) is evident in mice. By monitoring spatial and temporal structural changes during normal growth and in a mouse strain in which osteoclasts are non-functional (Src-null), we show that endosteal bone resorption is the main cause for the perinatal decrease in TMD. Mechanical testing revealed that this temporary decrease is correlated with reduced stiffness of the bones. We also show, by administration of a progestational agent to pregnant mice, that the decrease in TMD is not the result of parturition itself. This study provides a comprehensive view of perinatal long bone development in mice, and describes the process as well as the consequences of density fluctuation during this period.

Stress factors in local water-vole population

The physiologic mechanisms of stress have multiple effects on the adaptive capacity of an individual. Thus, the analysis of factors that determine the level of stress in animals in a changing environment acquires considerable ecologic and evolutionary significance. The results of long-term studies performed at the site of an irrigation canal, which is annually populated by water voles, are described in this paper. A high level of stress in male water voles has been found when the resources (food and mates) are scarce. The activation of adrenocortical function under the conditions of insufficient resources occurs due to the intensification of the intraspecific competition, which takes place after a decrease in both the food supply and the ratio of females in the local population. The effects of these factors are mediated by changes in spatial and ethologic structure of a studied population appearing as an increasing overlap of individual areas. The food supply and insufficient number of females affect the levels of glucocorticoids differently in resident and nonresident males. Our results suggest that social interactions act as actual stress factors in water voles, even if a considerable decrease occurs in water vole populations, which takes place in North Baraba due to the reduction of watering in the area and the decrease in territories suitable for summer habitation.

Spatial arrangement of collagen fibrils in normal and keratoconus human cornea studied by low‐frequency dielectric spectroscopy

AbstractPurpose Spatial structure of collagen lamellae of the human cornea is thought to be an important determinant of corneal rigidity. Analysis of the low‐frequency (1–107 Hz) dielectric spectra of the normal and keratoconus human cornea in the temperature range of 140‐300 K and for different hydration states were examined.Methods For the measurements, the 100 – 200 μm specimens containing the middle layers of corneal stroma were used. The 9 specimens of healthy, control corneas from Eye Bank were obtained with second microkeratom section during Ultra Thin‐DSAEK. The 12 specimens of keratoconus corneas were manually prepared from corneas removed during penetrating keratoplasty.Results Experimental results were interpreted in terms of ionic diffusion and space charge polarization according to the Sawada’s theory. The new presentation of the dielectric spectra, i.e.: (delta eps’/delta ln f)*f, was used. The presented method and the Sawada’s expression were applied to the analysis of the changes in spatial molecular structure of collagen fibril network in human cornea.Conclusion Fitting procedure of the theoretical function to the experimental data allowed us to determine two diffusive relaxation regions with two structural distance parameters ds, describing spatial arrangement of collagen fibrils in cornea.

Variability of local spatial structure in a wave-regenerated Abies forest

Although some studies have demonstrated temporal patterns of changes in spatial structure during forest development, few studies have examined the variability of spatial structure between stands at the same developmental stage. In the present study, we investigated variations of spatial structure between sites at the same developmental stage for three developmental stages (sapling, intermediate, and mature) in a wave-regenerated Abiesveitchii and Abies mariesii forest. The spatial structure of tree heights in each plot was analyzed by using the mark correlation and mark variogram methods, and the pattern of tree locations in each plot was analyzed by using the pair-correlation function. Analysis of the spatial height structure indicated that a size hierarchy between neighboring trees (a local size hierarchy) generally did not develop at the sapling stage. A local size hierarchy developed in most plots during the two later stages. There was no obvious difference among developmental stages in the spatial pattern of tree locations because of the large variation within each stage. Our results demonstrate that large variation in spatial structure existed between sites in the wave-regenerated Abies forest, even at the same developmental stage. The variability in spatial structure confirmed the importance of stochastic factors in forest dynamics.

Spatial structuring of submerged aquatic vegetation in an estuarine habitat of the Gulf of Mexico

Seasonal changes in spatial structure of biomass of submerged aquatic vegetation (SAV) and environmental variables were evaluated in Celestun Lagoon, an estuarine habitat in Mexico. Geostatistical techniques were used to evaluate spatial autocorrelation and to predict the spatial distribution by kriging. The relative contribution of 11 environmental variables in explaining the spatial structure of biomass of SAV was evaluated by canonical correspondence analysis. Spatial partitioning between species of SAV was evident: the seagrasses Halodule wrightii and Ruppia maritima dominated the seaward and central zones of the lagoon, respectively, whereas the green alga Chara fibrosa was constrained to the inner zone. The spatial structure and seasonal variability of SAV biomass were best explained by organic carbon in the sediments, salinity and total suspended solids in the water column. Analysis at different spatial scales allowed identifying the importance of spatial structure in biotic and abiotic variables of this estuarine habitat.

Spatial structure changes inside post-communist capital city of Bucharest

The paper focusses on the analyses of the recent development concerning post-socialist urban transformation of Bucharest, the Romanian country capital. The paper describes the spatial typology of metropolitan landscapes, and underlines the changes occurred inside the residential, commercial, services and industrial areas. The most noticeable occurrence is the urban sprawl and multiplication of the buildings and implicitly the diminishing of the agricultural area. It has been confirmed, at least theoretically, that spatial development of the largest cities determined a continuous decreasing of agriculture in the metropolitan area, landowners preferring selling or seeking to sell their land. The paper is empirically trying to argue the fact that post-socialist development of the land market in Bucharest metropolitan area determined a decline of agriculture in the city's proximity. It is also showing that at increasing distance from the Bucharest city agriculture still has its importance as subsistence activity - in the south-eastern part, or as market oriented - in the south-western part or in the northern border.

부산광역시 다핵구조의 공간적 변동성 측정

Recently metropolitan cities pursue multi centric urban spatial structure for sustainable development and efficient urban management. Thus, this study calculated population potential using data on population distributed among road nodes for the last 50 years, and based on the results. We measured the spatial variability of the multi centric structure of Busan Metropolitan City. According to the results, the multi centralization process has been continued up to recently in Busan Metropolitan City. As population potential is concentrated on sub centers, Hadan, Gupo and Haeundae areas were playing an increasingly powerful role as the center of the respective district, and Sasang and Dongrae had been losing their role as the center of their respective districts since 2000 and 1990, respectively. Additionally, in all the multi centric districts except Haeundae was observed the increase of oblongity, which is the change of spatial structure in an unbalanced way toward a specific area or direction.

Chiral recognition of metalaxyl enantiomers by human serum albumin: evidence from molecular modeling and photophysical approach

Metalaxyl is an acylamine fungicide, belonging to the most widely known member of the amide group. This task is aimed to scrutinize binding region and spatial structural change of principal vector human serum albumin (HSA) complex with (R)-/(S)-metalaxyl by exploiting molecular modeling, steady-state and time-resolved fluorescence, and circular dichroism (CD) approaches. According to molecular modeling, (R)-metalaxyl is situated within subdomains IIA and IIIA and the affinity of site I with (R)-metalaxyl is greater than site II, whereas (S)-metalaxyl is only located at subdomain IIA and the affinity of (S)-metalaxyl with site I is superior compared with that with (R)-metalaxyl. This coincides with the competitive ligand binding, guanidine hydrochloride-induced unfolding of protein, and hydrophobic 8-anilino-1-naphthalenesulfonic acid experiments; the acting forces between (R)-/(S)-metalaxyl and HSA are hydrophobic, π-π interactions, and hydrogen bonds, as derived from molecular modeling. Fluorescence emission manifested that the complex of (R)-/(S)-metalaxyl to HSA is the formation of adduct with an affinity of 10(4) M(-1), which corroborates the time-resolved fluorescence that the static type was operated. Furthermore, the changes of far-UV CD spectra evidence the polypeptide chain of HSA partially unfolded after conjugation with (R)-/(S)-metalaxyl. Through this work, we envisage that it can offer central clues on the biodistribution, absorption, and bioaccumulation of (R)-/(S)-metalaxyl.

Spatio-temporal patterns of intra-urban land use change in Beijing, China between 1984 and 2008

Urban internal structure is essential information for urban geography researchers and urban planners or managers. This research aims to examine the spatial structure changes of internal urban land use based on the interpreted datasets of 1984 and 2008. Spatio-temporal patterns of internal land use conversion and urban expansion are analyzed, and then dominant driving factors (e.g., social economy, population growth and urban planning) were identified. The results indicate that Beijing’s intra-urban layout has experienced tremendous adjustment from compact to disperse configure, otherwise its function objects have shifted from the major economic and industrial development before the 1990s to the combination with cultural, high-technological and inhabitable city at present. The dominant urban land use transformations include the relocation of industrial lands from core districts to suburban or other provinces, and the accelerating expansion of residential areas and green spaces for supplying the demand of housing and ecological protection. Although Beijing’s urban planning has experienced three major adjustments and improvement since the 1980s, its optimization of urban internal patterns still remains a challenge.

Changes in pupil diameter entrained by cortically initiated changes in attention

The diameter of the pupil is affected by changes in ambient illumination, color, spatial structure, movement, and mental effort. It has now been found that pupil diameter can be affected by cognitive processes. That is, it can be entrained by alternations between broadly spread and narrowly focused attention that are cued exogenously (attention is "summoned" by the cue) or endogenously (attention changes under the perceiver's intentional control). Pupil diameter also is affected by post-eye-blink constrictions that occur most often when attention is narrowed, and possibly by changes evoked by the near reflex, although changes in attention state parsimoniously account for the entirety of the results. Changes in pupil diameter produce differences in spherical aberration that alternately blur (when the pupil dilates) and sharpen the retinal image (when the pupil constricts), affecting the relative sensitivity of large receptive fields that mediate broadly spread attention compared with smaller receptive fields that mediate more narrowly focused attention. Results for endogenously cued, intentional changes in attentional spread provide definitive behavioral evidence for cortical feedback to subcortical nuclei that control pupil diameter, either directly or through pupil-constricting eye blinks. Analyses of convergent and divergent changes in eye position indicate that the near reflex was activated long after the initiation of relatively gradual attentionally cued changes in pupil diameter, and further, that when it occurs, the near reflex facilitates ongoing changes in pupil diameter.

The Analysis on the Spatial Characteristics and Inter-organizational Network Structure Change in the Creative Industry: Focused on Design Industry

The Analysis on the Spatial Characteristics and Inter-organizational Network Structure Change in the Creative Industry: Focused on Design Industry

Radiation stress and mean drift in continental shelf waves

The time- and depth-averaged mean drift induced by barotropic continental shelf waves (CSW’s) is studied theoretically for idealized shelf topography by calculating the mean volume fluxes to second order in wave amplitude. The waves suffer weak spatial damping due to bottom friction, which leads to radiation stress forcing of the mean fluxes. In terms of the total wave energy density E̅̅ over the shelf region, the radiation stress tensor component S̅11 for CSW’s is found to be different from that of shallow water surface waves in a non-rotating ocean. For CSW’s, the ratio S̅11/E̅ depends strongly on the wave number. The mean Lagrangian flow forced by the radiation stress can be subdivided into a Stokes drift and a mean Eulerian drift current. The magnitude of latter depends on ratio between the radiation stress and the bottom stress acting on the mean flow. When the effect of bottom friction acts equally strong on the waves and the mean current, calculations for short CSW’s show that the Stokes drift and the friction-dependent wave-induced mean Eulerian current varies approximately in anti-phase over the shelf, and that the latter is numerically the largest. For long CSW’s they are approximately in phase. In both cases the mean Lagrangian current, which is responsible for the net particle drift, has its largest numerical value at the coast on the shallow part of the shelf. Enhancing the effect of bottom friction on the Eulerian mean flow, results in a general current speed reduction, as well as a change in spatial structure for long waves. Applying realistic physical parameters for the continental shelf west of Norway, calculations yield along-shelf mean drift velocities for short CSW’s that may be important for the transport of biological material, neutral tracers, and underwater plumes of dissolved oil from deepwater drilling accidents.

Территориальная структура производительных сил Северо-Запада России в 2000—2010 годах

Regional disparities in Russia are examined by different sciences from different positions. Individual approaches are characteristic of economic geography, whose key concept is territorial division of labour. This article aims to describe and analyse the changes in spatial structure of economy of the Northwestern federal district over the first decade of the 21st century. The scientific significance of the study lies in that it offers a new methodology for assessing the economic efficiency of regions based on the use of easily available economic indicators. Its practical significance stems from the fact that the article identifies and described new trends in the development of Northwestern regions prevailing over the last years, which have not been comprehensively reflected in scientific literature to date. The main conclusions are as follows: after overcoming the crisis of the 1990s, the spatial development of economy of the North-West returns to the natural spatial principles typical of Russia of the early 20th century, which should be estimated as a positive development.

A Study on the Land Price Characteristicsin Urban Railway Station's Surrounding Zones of Gwangju City, Korea

This study shows that access to urban railway station affects the development of railway station's surrounding zone (RSSZ). For instance, the value of the property in RSSZ is likely to rise on the basis of the before and after the opening of a urban railway. Urban railway system is believed as an important solution to resolve worsening transport problems in metropolitan city. Also, the opening of a urban railway line is expected to affect the change of urban spatial structure, and to have more influence on land price of RSSZ.

Tracking Analysis of Forest Spatial Structure Change after Different Selective Cutting Intensities in a Natural Forest

Based on long-term tracking retest data and three structure parameters(mingling intensity,neighborhood comparison and uniform angle index),we investigated the effects of four different selective cutting intensities(low intensity of 13.0% in volume,medium intensity of 29.1%,high intensity of 45.8%,and over-high intensity of 67.1%) on forest spatial structure change in a natural forest.After low and medium selective cutting forest,plot average mingling and neighborhood comparison increased while high and over-high selective cutting decreased.Selective cutting did not change the forest spatial distribution pattern.However,the variety of forest plot showed aggregated distribution,and medium selective cutting in random distribution state forest number increased considerably.After low and medium selective cutting,forest spatial structure was optimized in general.