海岸带地类统计模型中DEM空间尺度优选方法

精确翔实、三维立体、尺度适宜的地类统计数据对于海岸带自然资源监测监管和生态保护具有重要意义,地类统计模型需要数字高程模型(digital elevation model,DEM)的支撑,然而当前鲜有DEM空间尺度与统计模型的适配性方面的研究。针对于此,该文提出了一种海岸带地类统计模型中DEM空间尺度优选方法,系统探讨了DEM空间尺度对地类统计模型的影响,从统计准确性、概括性、信息量和计算效率4个角度选取指标并构建评价模型,基于熵权法确定指标权重并加权计算得到DEM最优空间尺度。研究结果表明:①DEM采样间隔越大,对统计准确性和信息量的负向影响越明显,对信息概括性正向影响越显著;②准确性因子对DEM精细度要求高,为满足统计精度DEM分辨率不应超过30 m,而地貌概括则要求空间分辨率不能低于10 m;③空间操作计算时间与DEM格网数量呈线性正相关;④基于熵权法计算权重后综合评价,最优DEM空间尺度为10 m。该文形成的DEM空间尺度优选方法在海岸带自然资源及其他调查监测地类统计中具有通用性和可扩展性。

ARCGIS在珠海市土地利用总体规划图地类统计工作中的应用

土地利用总体规划是指根据土地资源的特点和社会经济发展的要求,在各级行政区域内对下一时期(通常为15年)的土地利用进行的总体安排。其实质是国民经济各部门之间有限土地资源的合理配置,即部门之间土地资源的时空配置(数量、质量和位置),这是通过土地利用结构来实现的。论文介绍了ARCGIS软件在珠海市土地利用总体规划图地类统计工作中的应用方法。

地类统计分析在土地利用动态监测中的应用——以南平市延平区为例

近几年,地理国情监测已经成了基础地理信息数据获取的重要手段,文中以福建省南平市延平区2016年和2020年的地理国情监测成果为数据基础,分析了4年中此地区的10个地物大类地表覆盖数据变化情况,以及城市的发展对自然资源造成的变化,从而反映出各种资源环境、生态和经济因素的空间分布和变化的规律,为此区域以后的发展方向提供了精准的数据支持。

基于模型构建器的永久基本农田地类分析统计方法

本文利用ArcGIS模型构建器,建立了永久基本农田地类分析统计工具箱,并在辽宁省100个县和1个公共水域进行了应用,完成了永久基本农田内2021年地类情况统计表。实践证明,使用模型构建器进行数据处理和统计,可以简化数据处理流程,提高工作效率,避免分析统计错漏与人为误差。

基于ArcGIS的地类面积统计工具研发与应用

地类面积统计是土地开发整理项目中一项至关重要的工作。目前,传统的地类面积统计方法需要大量的人工操作,速度慢,效率低,且容易出现问题。本文参照传统的统计方法,以ArcGIS 10.2为平台,运用Python语言进行脚本编写,并组建地类面积统计工具箱。最后以定边县白泥井镇北畔村土地开发项目和靖边县宁条梁镇黄蒿塘三期土地开发项目为对象进行地类面积统计实验,验证了该工具箱的运行精度与效率。

ARCGIS在地类面积统计中的应用

地类面积统计是很棘手,很辛苦的一项工作,本文介绍的方法可以实现快速准确的统计出地类面积,供大家参考学习。

Rocky Desertification Risk Zone Delineation in Karst Plateau Area:A Case Study in Puding County,Guizhou Province

Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management and prevention. We chose the middle and lower reaches of the Houzhai underground basin on the karst plateau in Puding County, Guizhou Province, China as the study area and selected land use type, elevation, slope, aspect, lithology and settlement buffer as the main driving factors of the rocky desertification. The potential risk of rocky desertification was quantifed with the factor-weights union method and statistical analysis method. Five grades of rocky desertification risk were delineated based on Geographic Information System. The extremely low, low, moderate, high and extremely high rocky desertification risk zones accounted for 5.01%, 44.17%, 33.92%, 15.59% and 1.30%, respectively. As a whole, the rocky desertification risk level was moderate because the area of low and moderate rocky desertification risk zones occupied 78.09% of the study area. However, more than half of the area （about 50.81%） was predicted to have moderate rocky desertification risk and above, indicating that the study area was subject to rocky desertification. Rocky desertification risk was higher in the southeast and lower in the northwest of the study area. Distinct differences in the distribution of rocky desertification risk zones corresponding to different factors have been found.

土地勘测定界高效一体化系统设计

通过对勘测定界作业流程和报备文件进行分析,针对传统方法中面积统计、数学要素标注、报备文件制作等过程步骤繁琐、手工编辑易出错、效率低等问题,以ArcGIS Engine为开发平台,结合VSTO文档级的Office定制开发技术,定制了一套适合规范标准的勘测定界系统。通过工作实践测试,该系统可大幅提高勘测定界测绘内业工作的效率和准确率。

STATISTICAL CLASSIFICATION AND CHARACTERISTICS ANALYSIS OF BINARY TROPICAL CYCLONES OVER THE WESTERN NORTH PACIFIC OCEAN

Using the 1949-2007 western North Pacific tropical cyclones (TCs) best-track data archived at the Shanghai Typhoon Institute of China Meteorological Administration for the western North Pacific from 1949 to 2007,both the characteristics of binary and multiple TCs and samples of interactions among TCs and multi-TCs are identified and statistically analyzed.According to the various features of individual TC tracks and interacting tracks,seven distinct types are proposed to describe the binary system of TCs and their interaction samples.The mean trajectories of the west and east component of binary TCs in each type are obtained using a new cluster analysis technique.These types are then analyzed in terms of landfall process,occurrence seasonality,coexistent lifetime,especially the large-scale patterns of atmospheric circulation.Finally,typical steering flows and conceptual models of the binary TCs at different phases are established based on six-hourly flow maps of the binary system and the averages are determined of the mean steering flow of ten representative binary TCs.Then,typical steering flows and conceptual models at the beginning,middle and final phase in each type are established to describe the large-scale circulation patterns of the binary system interaction types.

Spatial Variability of Soil Organic Carbon in a Watershed on the Loess Plateau

Soil organic carbon (SOC) has great impacts on global warming, land degradation and food security. Classic statistical and geostatistical methods were used to characterize and compare the spatial heterogeneity of SOC and related factors, such as topography, soil type and land use, in the Liudaogou watershed on the Loess Plateau of North China. SOC concentrations followed a log-normal distribution with an arithmetic and geometric means of 23.4 and 21.3 g kg-1, respectively, were moderately variable (CV = 75.9%), and demonstrated a moderate spatial dependence according to the nugget ratio (34.7%). The experimental variogram of SOC was best-fitted by a spherical model, after the spatial outliers had been detected and subsequently eliminated. Lower SOC concentrations were associated with higher elevations. Warp soils and farmland had the highest SOC concentrations, while aeolian sand soil and shrublands had the lowest SOC values. The geostatistical characteristics of SOC for the different soil and land use types were different. These patterns were closely related to the spatial structure of topography, and soil and land use types.

Monitoring urban land cover and vegetation change by multi-temporal remote sensing information

In order to analyze changes in human settlement in Xuzhou city during the past 20 years, changes in land cover and vegetation were investigated based on multi-temporal remote sensing Landsat TM images. We developed a hierarchical classifier system that uses different feature inputs for specific classes and conducted a classification post-processing approach to improve its accuracy. From our statistical analysis of changes in urban land cover from 1987 to 2007, we conclude that built-up land areas have obviously increased, while farmland has seen in a continuous loss due to urban growth and human activities. A NDVI difference approach was used to extract information on changes in vegetation. A false change information elimination approach was developed based on prior knowledge and statistical analysis. The areas of vegetation cover have been in continuous decline over the past 20 years, although some measures have been adopted to protect and maintain urban vegetation. Given the stability of underground coal exploitation since 1990s, urban growth has become the major driving force in vegetation loss, which is different from the vegetation change driven by coal exploitation mainly before 1990.

Estimation of Antropogenenic Pressure on Landscapes of Oasises （on Example of Mid and Lower Part of Zarafshan River）

The paper discusses about anthropogenic pressure classification system on landscape oasises. As a result, based on designed criteria rates a thematic map titled ＂Anthropogenic pressure and its consequences on landscapes oasises of mid and lower part of Zarafshan River Basin＂ was developed. The thematic map depicts realthionship between ecological conditions and population diseases along various landscape oasises of the Zarafshan river valley.

Abnormal Phenomena of Volume Strain before Large Earthquakes

This paper studies the imminent anomalies observed by the Sacks volume strainmeter in Erzhangying station and Tiantanghe station before 80 earthquakes with Ms≥ 7. 0 which took place from January 2011 to April 2014 all over the world. Then, preconditions for anomaly identification are put forward for complex earthquake cases. Statistical results show that volume strain observation has a better earthquake reflecting ability for earthquakes with magnitudes larger than 7. 0 and epicentral distance within 8000kin. In addition, these results also reflect that the volume strain observation can better reflect precursory anomalies of such earthquakes. Based on categorization and description of those anomalies, we divide the anomalies into three types, that is, earth tide distortion type, abrupt change type and slow earthquake type. Furthermore, the paper makes a statistical analysis of these types and preliminarily discusses their mechanical properties as well. According to research, volume strain anomaly has an indicative significance to future strong earthquakes in the world.

Comprehensive Research on Focal Mechanism Solutions in the Capital Circle Area of China

Comprehensive statistical analysis was performed on the basic features of focal mechanisms of 619 ML≥2. 0 earthquakes which occurred in the capital circle area from January 2002 to June 2010. By dividing the capital area into three studying regions based on regional tectonic characteristics,cluster analysis was conducted on the focal mechanisms of all subregions using the longest distance method in the statistical cluster analysis to study the characteristics of tectonic stress tensors. The result shows that dominant P-axis azimuth distribution is NNE-NEE and that of T-axis is NNW-NWW,most of the focal areas are controlled by a horizontal stress field and rupture is mainly of horizontal strike-slip. The maximum principal compression stress orientation is NE75° in the west,NE62° in the middle,and near EW in the east of the capital area. The regional tectonic stress field is characterized by horizontal compression.

Physical characteristics of Chinese Hakka

Using standard and internationally validated methods,86 anthropologic characteristics were determined in 650 male(305 from urban areas and 345 from rural areas) and 704 female(331 from urban areas,373 from rural areas) Chinese Hakka adults living in Guangdong and Jiangxi.The data were used to calculate 24 anthropologic indices,which were analyzed statistically.The physical characteristics of Hakka subjects were analyzed and compared with reference ethnic data.There were four main findings of this study.First,a small proportion of Hakka adults had an eye fold on the upper eyelid,but a large proportion had a mongoloid fold.The eye slits were narrow in most adults,had a medium nasal root height and straight bridges,and most of the external angles were prominent.The nasal base was upturned in most men.The distributions of the three types of nasal base in women were similar.The proportions of subjects with middle and high alae nasi heights were high and similar.Males with a maximum nostril diameter were mostly classified as transverse and oblique,while many women were classified as transverse and had relatively wide alae nasi.The round lobe type was the most common.Upper lip skin height was mostly classified as medium.Lips were classified as thin.The hair was black,eyes were brown,and the skin was yellowish.Second,the head length was long in male Hakka.The minimum frontal breadth,face breadth,lip height,and interocular breadth were similar to those of North-Asian populations.Meanwhile,head breadth,morphological facial height,nose breadth,mouth breadth,and nose height were similar to those of South-Asian populations.Head length was long in female Hakka.The minimum frontal breadth,face breadth,lip height,and interocular breadth were similar to those of North-Asian populations.Head breadth,nose breadth,and mouth breadth were similar to those of South-Asian populations.Third,the stature of male and female Hakka in urban and rural areas was classified as medium.The proportions of male and female Hakka classified as mesocephaly(length-breadth index of the head),hypsicephalic type,metriocephalic type(breadth-height index of the head) mesorrhiny,long trunk,subbrachyskelic type,broad shoulder breadth,and narrow distance between iliac crests were higher than those of other types.Finally,principal component analyses showed that the physical characteristics of Hakka were between those of South-Asian and North-Asian ethnic populations,but were generally closer to those of North-Asian populations in China.

Spatial Variability of Soil Organic Carbon and Related Factors in Jiangsu Province,China

Soil organic carbon (SOC) plays a key role in the global carbon cycle.In this study,we used statistical and geostatistical methods to characterize and compare the spatial heterogeneity of SOC in soils of Jiangsu Province,China,and investigate the factors that influence it,such as topography,soil type,and land use.Our study was based on 24 186 soil samples obtained from the surface soil layer (0-0.2 m) and covering the entire area of the province.Interpolated values of SOC density in the surface layer,obtained by kriging based on a spherical model,ranged between 3.25 and 32.43 kg m 3.The highest SOC densities tended to occur in the Taihu Plain,Lixia River Plain,along the Yangtze River,and in high-elevation hilly areas such as those in northern and southwest Jiangsu,while the lowest values were found in the coastal plain.Elevation,slope,soil type,and land use type significantly affected SOC densities.Steeper slope tended to result in SOC decline.Correlation between elevation and SOC densities was positive in the hill areas but negative in the low plain areas,probably due to the effect of different land cover types,temperature,and soil fertility.High SOC densities were usually found in limestone and paddy soils and low densities in coastal saline soils and alluvial soils,indicating that high clay and silt contents in the soils could lead to an increase,and high sand content to a decrease in the accumulation of SOC.SOC densities were sensitive to land use and usually increased in towns,woodland,paddy land,and shallow water areas,which were strongly affected by industrial and human activities,covered with highly productive vegetation,or subject to long-term use of organic fertilizers or flooding conditions.