Land use and cover change and influencing factor analysis in the Shiyang River Basin,China

Land use and cover change(LUCC)is the most direct manifestation of the interaction between anthropological activities and the natural environment on Earth's surface,with significant impacts on the environment and social economy.Rapid economic development and climate change have resulted in significant changes in land use and cover.The Shiyang River Basin,located in the eastern part of the Hexi Corridor in China,has undergone significant climate change and LUCC over the past few decades.In this study,we used the random forest classification to obtain the land use and cover datasets of the Shiyang River Basin in 1991,1995,2000,2005,2010,2015,and 2020 based on Landsat images.We validated the land use and cover data in 2015 from the random forest classification results(this study),the high-resolution dataset of annual global land cover from 2000 to 2015(AGLC-2000-2015),the global 30 m land cover classification with a fine classification system(GLC_FCS30),and the first Landsat-derived annual China Land Cover Dataset(CLCD)against ground-truth classification results to evaluate the accuracy of the classification results in this study.Furthermore,we explored and compared the spatiotemporal patterns of LUCC in the upper,middle,and lower reaches of the Shiyang River Basin over the past 30 years,and employed the random forest importance ranking method to analyze the influencing factors of LUCC based on natural(evapotranspiration,precipitation,temperature,and surface soil moisture)and anthropogenic(nighttime light,gross domestic product(GDP),and population)factors.The results indicated that the random forest classification results for land use and cover in the Shiyang River Basin in 2015 outperformed the AGLC-2000-2015,GLC_FCS30,and CLCD datasets in both overall and partial validations.Moreover,the classification results in this study exhibited a high level of agreement with the ground truth features.From 1991 to 2020,the area of bare land exhibited a decreasing trend,with changes primarily occurring in the middle and lower reaches of the basin.The area of grassland initially decreased and then increased,with changes occurring mainly in the upper and middle reaches of the basin.In contrast,the area of cropland initially increased and then decreased,with changes occurring in the middle and lower reaches.The LUCC was influenced by both natural and anthropogenic factors.Climatic factors and population contributed significantly to LUCC,and the importance values of evapotranspiration,precipitation,temperature,and population were 22.12%,32.41%,21.89%,and 19.65%,respectively.Moreover,policy interventions also played an important role.Land use and cover in the Shiyang River Basin exhibited fluctuating changes over the past 30 years,with the ecological environment improving in the last 10 years.This suggests that governance efforts in the study area have had some effects,and the government can continue to move in this direction in the future.The findings can provide crucial insights for related research and regional sustainable development in the Shiyang River Basin and other similar arid and semi-arid areas.

Spatiotemporal Evolution of Ecosystem Service Value in Caohai National Nature Reserve

Wetland ecosystems are important regulators of global climate change.Studying the spatiotemporal changes and driving mechanisms of their ecosystem service values(ESV)is beneficial for the sustainable development of wetlands.This paper uses the equivalent factor method,based on land use changes,to reveal the spatiotemporal evolution of the ecosystem service value in the Caohai National Nature Reserve(CNNR).The results show the following:①from 2000 to 2020,there was a significant decrease in the core zone s arable land area,with an increase in forest and water areas.Construction land mainly increased in the experimental area,and the grassland area showed a fluctuating change of first increasing and then decreasing;②in 2000,2010,and 2020,the ecosystem service value of the study area was 302 million,296 million,and 325 million yuan,respectively,showing a trend of fluctuating growth,with the value of wetland ecosystems playing a dominant role;③regulatory services are the main contributors to the ecosystem service value in the study area,with a contribution rate of 60%.Hydrological regulation is the ecosystem function with the highest value in wetland ecosystem services,contributing more than 35%to the ESV in all three periods;④in terms of spatial distribution,the core zone s ecosystem service value is dominant.Looking at the total ecosystem service value of the region,the core zone>the experimental area>the buffer zone.In terms of ESV per unit area,the core zone(89000 yuan/hm^(2))is significantly higher than the buffer zone(39100 yuan/hm^(2))and the experimental area(15800 yuan/hm^(2)).The study can provide a basis for research and spatial management of ecosystem services in wetland ecosystems and nature reserves.

Impact of Land Use Change on Vegetation Carbon Storage During Rapid Urbanization:A Case Study of Hangzhou,China

Land use changes have significant impacts on the carbon balance in an urban ecosystem.When there is rapid development in urbanizing regions,land use changes have a dramatic effect on vegetation carbon storage(VCS).This study investigates the impact of land use change on VCS in a period of rapid urbanization in Hangzhou,China.The results show that:1)from 2000 to 2015,land use in Hangzhou underwent huge changes,mainly reflected in decrease in cropland and wetland and the increased settlement.More than 34.58%of the land was transformed,and the land use changes are primarily characterized by a significant decrease in cropland due to the occupation by settlement.2)over the 15 years,changes in land use led to a decrease of 3.93×10^(5) t of VCS in the urban ecosystem.The large-scale transformation of cropland and wetland,which have a comparatively high carbon density,into land for settlement exerted a negative impact on VCS.3)The central city,which with the Circle-E/I/O mode,had the lowest comprehensive land use dynamic degree,leading to moderate land use change and an increase in VCS;Yuhang and Xiaoshan,which with Multicore-E/O/I mode and Fan-E/O/I modes,had a higher comprehensive land use dynamic degree,drastic changes in land use,and a decrease in VCS.This study proposes a reliable method of estimating changes in VCS,clarifies the relationship between land use change and VCS during rapid urbanization,and provides recommendations for sustainable urban development.

THE DRIVING FORCES OF LAND USE/COVER CHANGE INTHE UPSTREAM AREA OF THE NENJIANG RIVER

ABSTRACT: Based on the Landsat 5 and Landsat 7 TM images, the land use/cover change was detected in the upstream area of the Nenjiang River between 1995 and 2000. With the spatial analysis techniques of GIS, the maps of land use degree and its change within this period were produced. To identify the causes of changes, elevation and slope were regarded as the main natural influencing factors and were transformed from coverage format to grid format within GIS. The Thiesson polygon method was used to the spatial allocation of socio-economic factors including human population, livestock numbers, mechanizing power of farming and the nearest distance from the changed pixel to the trunk stream and to main settlements, thereby the spatial relationship between land use degree change and socio-economic factor variation was analyzed. According to results of the spatial correlation, the determinants of changes in land use/cover, i. e. elevation, slope, population density change, livestock increase were extracted quantitatively in this area. At last, the spatial multi-linear regression model of land use degree change was developed as follows: △ La = 11. 037-4. 512 * eleva-tion-0. 298 * slope + 0. 292 *△ population + 2. 596 *△ livestock.

Extraction of LUCC with different methods and threshold value

The research of land use and land cover (LUCC) is an important aspect in the global change research. The goal of this study is to find methods of extraction of LUCC’s change outlined and change type from remotely sensed data. Take the country of Fengxian in Shanghai as an example, it was supposed two steps to finish extraction of LUCC information: the first step was to use different methods, which is used to outline change areas; the second step include methods of false composing of two-temporal and threshold value. Through combining two methods, a model rule is built and the LUCC product is obtained, four kinds of change type within the study area are given, and the results are obvious. Finally, the results support the application of the high resolution image and tasseled cap composition (greenness and wetness) in the specific regional too.

Method of Non Destructive Geophysical Mapping of the Environment

Problem statement: The method of non-destructive testing is needed in different aspects of geology, geomechanics and archeology, for instance: by testing the state of rock massifs in sault, kimberlites or rock shock mines, ancient archeological objects, or mapping for locating the wells drilling. The best method for solution these problems is based on using induction multi frequency electromagnetic field with use control sources on 3D planshet system of observation. Applied methods and design: Such method was developed at the Institute of Geophysics, Ural Branch of the Russian Academy of Sciences that allows its use to solve complex geological problems for mapping and monitoring the state of the environment. Its use allows the observation system to be used in such way that, on the one hand, it achieves flexible tunable detail of observations, and on the other hand, it organizes an input database that is close to the domain of definition of the inverse problem operator in the class of layered-block models with local hierarchical inclusions. This allows using regularization methods to obtain solutions that are in the class of equivalent, close to true. The specific possibilities of its use are determined by the technical side: the power of the excitation source, the sensitivity of the receiving system. Typical results: It had been developed a new method of mapping, processing and interpretation, realized in a set of programs that allow seeing the result of the searching structure of the environment in real time (that is after receiving some results during one day, we can see the results of the geoelectrical features of the structure and the state of that part of the environment). It had been suggested a three staged conception of interpretation that can be used not only for interpretation electromagnetic induction data and dynamic seismic data. Concluding note (Practical value/implications): In the considered case, this method contributed to the study of altered forms of kimberlitic bodies. The method underwent geological verification in various geological conditions where it had been used for mapping the geoelectrical structure. This allows us to offer a method for the development of innovative technology in the search for hydrocarbons in complex geological structures. The method was used in Egypt for research ancient archeological objects, located in Alexandria.

Temporal and spatial pattern of land use change in Ji’nan since the late 1980s

Taking Ji’nan as a case study area,this paper aims to analyze the land use changes from late 1980s to 2010 by using remote sensing data.The geographic information systems(GIS)method and land use transfer matrix methods were used to calculate the temporal and spatial differences of land use change.From the analysis of the land use transfer matrix,the most significant change is the cultivated land being transferred to construction land.From late 1980s to 2010,a total of 20615 hectares of cultivated land had been converted to construction land,accounting for 11.04%of the cultivated land in all.Through the analysis of the factors of land use transition,the human dimensions that had influenced the land use changes were population factor and economy factor.

1960-2010年黑河流域冰川变化的遥感监测

利用1960年地形图、1990年、2000年和2010年TM影像,采用基于冰雪指数(NDSII)和原始波段的面向对象解译方法,提取黑河流域4个时期的冰川分布,结合30m分辨率的DEM数据,利用遥感、地理信息系统技术对冰川的时空分布变化及原因和不确定性进行分析.结果表明:从1960-2010年50a间黑河流域上游冰川持续退缩,面积共减少138.90km2,减少率为35.6%,平均每年减少2.78km2,祁连山中段冰川属于强烈退缩型.祁连山中段黑河流域冰川主要分布在海拔4 200～5 300m之间,冰川分布下限为海拔4 000m;冰川退缩主要发生在低海拔地区,冰川的退缩上限为海拔4 600m.气温的显著上升是研究区冰川退缩的关键因素,气候持续变暖将会导致冰川退缩加剧.

中国当代文学史研究中的几个问题

自1959年至新世纪初,中国当代文学史研究可分为四个阶段。1980年代中后期以来,中国当代文学史研究主体已明显分化为"史性研究"与"当下批评"两部分;中国当代文学史经典的指认与重释活动,不仅贯穿于中国当代文学史研究的四个阶段之中,而且各个时期对经典指认的主导思维与其时的文化思潮、学术思潮的启迪和制约密不可分;中国当代文学史研究方法的更移,具体体现为从"主题本位论"到"审美本位论",再到"价值多元性体认"等方面的梯次置换。

气候变化背景下荒漠草原牧民退牧意愿及其影响因素分析——以张掖市平山湖乡为例

近年来,气候变化对自然生态环境造成了极大破坏,特别是对原本生态环境脆弱,自然灾害频发的荒漠草原更是雪上加霜,严重影响了牧民的生产生活。只有鼓励更多牧民参与退牧还草项目,才能促使当地经济快速发展。基于此,本文利用甘肃省张掖市平山湖乡全乡牧民的调查数据,首先采用Logistic回归模型分析牧民退牧意愿的影响因素,然后运用解释结构模型分析各影响因素之间的关系。研究表明:牧民受教育程度、家庭拥有的饲草地面积、牧民对气候变化的认知、牧民对草原荒漠化的认知、牧民对退牧补贴政策的认知,对牧民退牧意愿呈现出正向影响,而家庭拥有的羊只数量对牧民退牧意愿呈现出负向影响,牧民年龄和外出务工率对牧民退牧意愿影响不显著。其中,文化程度、羊只数量、饲草地面积是深层原因;对退牧补贴政策的认知和对草原荒漠化的认知是间接原因;对气候变化的认知是直接原因。

2008—2013年晋北地区土地利用/覆被变化研究

旨在了解人类活动对晋北地区土地利用/覆被变化(LUCC)的影响,为研究区合理利用土地资源、优化土地利用格局以及促进区域经济社会协调发展提供科学依据。利用晋北地区2008—2013年的TM遥感影像数据,在ERDAS、ArcGIS等软件的技术支持下,解译影像处理数据并建立土地利用变化转移矩阵,对研究区域近5年来土地利用/覆被变化进行研究。结果表明:2008—2013年期间,晋北地区耕地面积减少62561.10 hm^2,林地增加55774.23 hm^2,居民工矿建设用地增加22895.49 hm^2,草地减少15395.60 hm^2,水域面积增加1090.24 hm^2,未利用地面积减少1803.29 hm^2。这与研究区域在研究时段内大量退耕还林还草的生态建设、城镇化快速发展、经济持续增长等人类活动相关。综上,2008—2013年期间,晋北地区土地利用与覆被发生了较大变化。

Is the runoff coefficient increasing or decreasing after ecological restoration on China’s Loess Plateau?

The“Grain for Green”project(GGP)was launched in 1999 on China’s Loess Plateau to reduce soil erosion,which had far-reaching impacts on the local eco-hydrological processes.In this study,we use monthly runoff depth and precipitation datasets spanning 1961 to 2015 for 16 primary basins of the plateau to reveal changes in runoff generation capacity before and after the GGP.We use a Budyko-based elasticity method to calculate the runoff depth(R_(1))and runoff coefficient(C_(1))exclusively attributable to land use/cover change.Results indicate that the mean annual runoff coefficients(Co)decline by 26%—76%from the periods 1961—1999 to 2000—2015.The annual observed runoff depth(Ro)and C_(0)for 75%of basins show significant downward trends during 1961—1999;after the implementation of the GGP,both annual Ro and annual Co for over 50%of basins show upward trends.The study further finds that the increase of erosive rainfall during the period 2000-2015,whose mean increasing rate reaches 4.6 mm/year,is the main reason for the upward trends of Ro and Co.After removing the effect of precipitation variation during this period,we find that 11 out of 16 basins show decreased trends for Cj,with the downward rate between 2.4%and 6.0%per year.The reduction rate in semi-arid areas is about four times the rate in semi-humid areas.The results remind us to consider the carrying capacity of local water resources when implementing soil and water conservation measures across the Loess Plateau.

Implicit Shape Reconstruction of Unorganized Points Using PDE-Based Deformable 3D Manifolds

In this work we consider the problem of shape reconstruction from an unorganized data set which has many important applications in medical imaging, scientific computing, reverse engineering and geometric modelling. The reconstructed surface is obtained by continuously deforming an initial surface following the Partial Differential Equation (PDE)-based diffusion model derived by a minimal volume-like variational formulation. The evolution is driven both by the distance from the data set and by the curvature analytically computed by it. The distance function is computed by implicit local interpolants defined in terms of radial basis functions. Space discretization of the PDE model is obtained by finite co-volume schemes and semi-implicit approach is used in time/scale. The use of a level set method for the numerical computation of the surface reconstruction allows us to handle complex geometry and even changing topology,without the need of user-interaction. Numerical examples demonstrate the ability of the proposed method to produce high quality reconstructions. Moreover, we show the effectiveness of the new approach to solve hole filling problems and Boolean operations between different data sets.

2-D Seismic Reflection Method Using Iso Velocity Method of Mianwali Area

A seismic reflection of Line 12-B belonging to Mianwali Re-entrant was acquired and processed for 2-D interpretation. The line orients itself NNE-SSW direction. The sections have the shot points from VP-199 to VP-1044. Eleven Reflectors R1, R2, R3, Base Miocene, Pinchout P1, P2, P3, P4, P5P6 (Pinchout) are marked and a basement has been marked and interpreted. All the reflectors above the basement show a downward bending at the center. The depth of each reflector was calculated by iso velocity contour map method. The depth section obtained by this method shows stratigraphic features like Pinchouts. The reflectors are then correlated with the subsurface structures and stratigraphy of the area.

Model of Universe as Described by Dynamic Universe Model

In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the matter here, we will see in part 1: about the Galaxy life cycle, where the birth and death of Galaxies discussed. Probably Universe gives guidance for the movement of Galaxies. We call this Part 1: Thinking and Reproducing Universe or Mindless Universe? (Galaxy life cycle). We see every day Sun, Stars, Galaxies etc., dissipating enormous energy in the form of radiation by the way of fusion of Hydrogen to helium. So after sometime all the Hydrogen is spent and Universe will die, is it not? … Dynamic Universe Model says that the energy in the form of electromagnetic radiation passing grazingly near any gravitating mass changes in frequency and finally will convert into neutrinos (mass). Hence Dynamic Universe Model proposes another process where energy will be converted back into matter and the cycle energy to mass to energy continues, sustaining the Universe to maintain this present status for ever in this form something like a Steady state model without any expansion. This we will see in Part 2: Energy - Mass - Energy Cycle. After converting energy into mass “how various elements are formed and where they are formed?” will be next logical question. Dynamic Universe Model says that these various particles change into higher massive particles or may get bombarded into stars or planets and various elements are formed. Here we bifurcate the formation of elements into 6 processes. They are for Elementary particles and elements generated in frequency changing process, By Cosmic rays, By Small stars, By Large Stars, By Super Novae and Manmade elements By Neutron Stars. This we will discuss in Part 3: Nucleosynthesis.

姬塬地区长9段致密砂岩储层流体性质解释方法研究与应用

鄂尔多斯盆地姬塬地区长9段为典型的低孔低渗储层,受物性影响,储层非均质性强,油水关系相对复杂,同时普遍发育低阻油层、高阻水层,导致常规测井、录井手段难以对储层流体性质进行有效的识别。利用气测、地化、核磁共振等录井技术,结合试油资料,形成了基于参数谱图形态分析的气测、地化以及核磁共振谱图解释法;通过分析姬塬地区长9段储层不同流体性质各项录井参数的变化特征,优选气测全烃、气测湿度比、地化P_(g)、核磁孔隙度等敏感参数,建立了气测全烃与湿度比、地化P与核磁孔隙度两个交会图板。该套解释方法在姬塬地区长9段致密砂岩储层应用45口井,综合解释符合率达82.3%,为油田的高效开发提供了技术保障。

《易传》解《易》方法析论

本文通过《易传》来研究解《易》方法,共分四个部分:一、认为卦名反映一卦之主旨,《杂卦传》《大象传》为探寻卦名意义作过若干努力。二、认为《大象传》反映《周易》之精髓,它揭示了《周易》以六十四卦为形式探讨在不同的境遇下,君子所应具备的境界。三、《说卦传》揭示了《周易》取象比类的思维方法。四、《彖传》《系辞传》揭示了"当位"说、"得中"说、"正应"说、"贵贱"说等解卦方法。

Experiments and analysis of gold disk targets irradiated by smoothing beams of Xingguang Ⅱ facilities with 350 nm wavelength

Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-Ⅱ) laser facilities with 350 nm wavelength,0.6 ns pulse width and 20-80 Joules energies. Laser absorption,light scattering and X-ray conversion were experimentally investigated. The experimental results showed that laser ab-sorption and scattered light were about 90% and 10%,respectively,under focusing irradiation,but the laser absorption increased 5%-10% and the scattered light about 1% under the condition of beam smoothing. Compared with the case of fo-cusing irradiation,the laser absorption was effectively improved and the scattered light remarkably dropped under uniform irradiation; then due to the decrease in laser intensity,X-ray conversion increased. This is highly advantageous to the in-ertial confinement fusion. However,X-ray conversion mechanism basically did not change and X-ray conversion efficiency under beam smoothing and focusing irra-diation was basically the same.