Assessing the Impacts of Land Use and Land Cover Changes on Hydrology of the Mbarali River Sub-Catchment. The Case of Upper Great Ruaha Sub-Basin, Tanzania

Intensification of agricultural land use and population growth from 1990-2017 has caused changes in land cover and land use of the Mbarali River sub-catchment which is located in the Upper Great Ruaha Sub basin, Tanzania. This has affected the magnitude of the surface runoff, total water yield and the groundwater flow. This study assesses the impacts of the land cover and land use changes on the stream flows and hydrological water balance components (surface runoff, water yield, percolation and actual evapotranspiration). The land use and land cover (LULC) maps for three window period snapshots, 1990, 2006 and 2017 were created from Landsat TM and OLI_TIRS with the help of QGIS version 2.6. Supervised classification was used to generate LULC maps using the Maximum Likelihood Algorithm and Kappa statistics for assessment of accuracy. SWAT was set up and run to simulate stream flows and hydrological water balance components. The assessment of the impacts of land use and land cover changes on stream flows and hydrological water balance component was performed by comparing hydrological parameters simulated by SWAT using land use scenarios of 2006 and 2017 against the baseline land use scenario of 1990. Accuracy of LULC classification was good with Kappa statistics ranging between 0.9 and 0.99. There was a drastic increase in areal coverage of cultivated land, for periods 1990-2006 (5.84%) and 2006-2017 (12.05%) compared to other LULC. During 2006 and 2017 surface runoff increased by 4% and 9% respectively;however, water yield increased by only 0.5% compared to 1990 baseline period. This was attributed to increased proportion of cultivated land in the sub-catchment which has a high curve number (59.60) that indicates a higher runoff response and low infiltration rate.

Assessing the Effect of Natural Controls and Land Use Change on Sediment Yield in a Major Andean River:The Magdalena Drainage Basin,Colombia

马格达莱纳河是哥伦比亚安第斯山区的一个世界级的河流网络，该河流年产沙量约为150Mt，是全世界10大主要产沙河流之一。在本研究中，我们探讨主要自然因子和人类活动对马格达莱纳河流域产沙模式的影响，重建该区森林砍伐和农业活动时空模式，探讨土地利用变化与产沙趋势的关系。我们的研究结果表明，整个马格达莱纳河流域的产沙量可以用自然变量（包括径流量和最大河水流量）来解释。这两个因子解释了产沙量58％的变化。含沙率和土地利用的时间分析表明，在过去10～20年里流域侵蚀呈现增加的趋势。许多人类活动的影响，包括森林覆被在20年里减小了近40％．农业和牧场增加了65％、土壤保持差、开矿活动，以及城市化的加速，都促进了该地区域尺度上产沙量的增加。

Assessment of degraded mattoral land using remote sensing im-agery in Guadalteba Area,Spain

Natural land cover information is important for analysing and understanding of the current terrestrial situation, especially in the study area that is facing the environmental deteriorating increasingly. The study combined the remote sensing Aster data and ground truth to improve 2001 land cover map of Guadalteba area in Spain, and increased the accuracy from 47% to 70%. The general land cover map produced about the Guadalteba study area outlines the distribution of the vegetation type and the current natural land cover in the area. Based on this improved general land cover map, the natural cover map gave an indication of the present location of nature and agriculture areas. The shrub land degradation map identified location of various shrub/matorral areas and different levels of degradation. The further analysis and discussion were done. The output maps indicated that much of the natural cover mostly dominated by formations of shrubs has been changed to agriculture and other land uses. It is observed that shrubland covers a small percentage, approximately 9% of the study area, due to land degradation in most parts caused by human interfere. Keywords Accuracy assessment - Aster - Land cover map - Matorral degradation map - Remote Sensing CLC number S757.3 Document code A Foundation item: This paper was partly sponsored by NFP (Netherlands Feliowship Program) and National Strategic Project “Environmentally Sound Forest Management Techniques and Models in Natural Forest in Northeast China” (2001BA510B0702) respectively.Biography: XING Yan-qiu (1970-), female, Lecturer, in College of Engi neering and technology Northeast Forestry University. Harbin 150040. P. R. ChinaResponsible editor: Song Funan

Establishment of Monitoring and Assessment Index System of Land Degradation of Farmland Ecosystems at Small-scale

The research established land degradation monitoring and assessment in- dex system of farmland ecosystem under influence of human activities, including farming system, measures, mulch residuals, fertilizer pollutions, pesticide pollution, irrigation method, salt content of soils, engineering measures of discharging alkali, agricultural protection forests and poverty. The indices of the system are accessible, and convenient for operation, which is suitable for land managers self-monitoring, re- ducing irrational farming activities, improving farmland productivity and preventing farmland degradation.

Accuracy Assessment of Land Use/Land Cover Classification Using Remote Sensing and GIS

Remote sensing is one of the tool which is very important for the production of Land use and land cover maps through a process called image classification. For the image classification process to be successfully, several factors should be considered including availability of quality Landsat imagery and secondary data, a precise classification process and user’s experiences and expertise of the procedures. The objective of this research was to classify and map land-use/land-cover of the study area using remote sensing and Geospatial Information System (GIS) techniques. This research includes two sections (1) Landuse/Landcover (LULC) classification and (2) accuracy assessment. In this study supervised classification was performed using Non Parametric Rule. The major LULC classified were agriculture (65.0%), water body (4.0%), and built up areas (18.3%), mixed forest (5.2%), shrubs (7.0%), and Barren/bare land (0.5%). The study had an overall classification accuracy of 81.7% and kappa coefficient (K) of 0.722. The kappa coefficient is rated as substantial and hence the classified image found to be fit for further research. This study present essential source of information whereby planners and decision makers can use to sustainably plan the environment.

Assessment of the cropland classifications in four global land cover datasets： A case study of Shaanxi Province, China

Accurate and reliable cropland surface information is of vital importance for agricultural planning and food security monitoring. As several global land cover datasets have been independently released, an inter-comparison of these data products on the classification of cropland is highly needed. This paper presents an assessment of cropland classifications in four global land cover datasets, i.e., moderate resolution imaging spectrometer （MODIS） land cover product, global land cover map of 2009 （GlobCover2009）, finer resolution observation and monitoring of global cropland （FROM-GC） and 30-m global land cover dataset （GlobeLand30）. The temporal coverage of these four datasets are circa 2010. One of the typical agricultur- al regions of China, Shaanxi Province, was selected as the study area. The assessment proceeded from three aspects： accuracy, spatial agreement and absolute area. In accuracy assessment, 506 validation samples, which consist of 168 cropland samples and 338 non-cropland ones, were automatically and systematically selected, and manually interpreted by referencing high-resolution images dated from 2009 to 2011 on Google Earth. The results show that the overall accuracy （OA） of four datasets ranges from 61.26 to 80.63%. GlobeLand30 dataset, with the highest accuracy, is the most accurate dataset for cropland classification. The cropland spatial agreement （mainly located in the plain ecotope of Shaanxi） and the non-cropland spatial agreement （sparsely distributed in the south and middle of Shaanxi） of the four datasets only makes up 33.96% of the whole province. FIROM-GC and GlobeLand30, obtaining the highest spatial agreement index of 62.40%, have the highest degree of spatial consistency. In terms of the absolute area, MODIS underestimates the cropland area, while GlobCover2009 significantly overestimates it. These findings are of value in revealing to which extent and on which aspect that these global land cover datasets may agree with each other at small scale on each ecotope region. The approaches taken in this study could be used to derive a fused cropland classification dataset.

Soil Heavy Metal Pollution and Health Risk Assessment of Abandoned Land in Coal Mining Areas in Xingren County

Total contents of heavy metals （ Pb, Cr, Cd, Hg, As, Cu, Zn, and Ni） in 68 soil samples were determined to evaluate the contamination level of soil from five coal mine areas in Xingren County, Guizhou province. The pollution levels of heavy metals were characterized by anthro- pogenic influence multiple, and the pollution of heavy metal in soil was evaluated using geo-accumulation index. Based on the health risk models recommended by the U.S. Environmental Protection Agency （ US EPA）, the health risks of heavy metals in the soils were assessed. The results showed that the abandoned land in the five coal mining areas were contaminated by heavy metals, and the order of pollution levels of eight heavy metals was As 〉 Pb 〉 Cu 〉 Hg 〉 Ni 〉 Cr 〉 Cd 〉 Zn. The soils suffered moderate-heavy pollution from As and Pb, and the contents of As and Pb in the soils were 13.16 and 4.76 times higher than the background values of Guizhou Province, followed by Cu, Hg and Ni , while soil pollution from Cr, Cd and Zn was mild. The order of non-caminogenic risks of the heavy metals in the soils was As 〉 Pb 〉 Cr 〉 Ni 〉 Cu 〉 Hg 〉 Cd 〉 Zn, and the non-carcinogenic dsk value of As was higher than that its threshold value 1, which indicated that As had a high potential health risk to adults and children. The order of carcinogen risks of the four heavy metals was As 〉 Cd 〉 Cr 〉 Ni, and the carcinogenic risk value of As was higher than its threshold value, indicating that As had a high carcinogenic risk to adults and children. The carcinogenic risk values of other three heavy metals （ Cd, Cr and Ni） were lower than the threshold value, so they had no carcinogenic risk to human health. Moreover, children were more sensitively affect- ed by heavy metals from the abandoned land. Therefore, the health of children in such areas should be paid more attention to. The HI value of the eight heavy metals to children was seven times higher than that to adults. The contribution rate of HQAs to HI was about 88%, and the contribution rate of CRA, to TCR was about 98%, so As was the most crucial factor influencing non-carcinogenic and carcinogenic dsk in the abandoned soils.

GIS-based Effect Assessment of Soil Erosion Before and After Gully Land Consolidation: A Case Study of Wangjiagou Project Region, Loess Plateau

The Loess Plateau is one typical area of serious soil erosion in the world. China has implemented ′Grain for Green′(GFG) project to restore the eco-environment of the Loess Plateau since 1999. With the GFG project subsidy approaching the end, it is concerned that farmers of fewer subsidies may reclaim land again. Thus, ′Gully Land Consolidation Project′(GLCP) was initiated in 2010. The core of the GLCP was to create more land suitable for farming in gullies so as to reduce land reclamation on the slopes which are ecological vulnerable areas. This paper aims to assess the effect of the GLCP on soil erosion problems by studying Wangjiagou project region located in the central part of Anzi valley in the middle of the Loess Plateau, mainly using the revised universal soil loss equation(RUSLE) based on GIS. The findings show that the GLCP can help to reduce soil shipment by 9.87% and it creates more terraces and river-nearby land suitable for farming which account for 27.41% of the whole study area. Thus, it is feasible to implement the GLCP in places below gradient 15°, though the GLCP also intensifies soil erosion in certain places such as field ridge, village land, floodplain, natural grassland, and shrub land. In short, the GLCP develops new generation dam land and balances the short-term and long-term interests to ease the conflicts between economic development and environmental protection. Furthermore, the GLCP and the GFG could also be combined preferably. On the one hand, the GFG improves the ecological environment, which could offer certain safety to the GLCP, on the other hand, the GLCP creates more farmland favorable for farming in gullies instead of land reclamation on the slopes, which could indirectly protect the GFG project.

Heavy Metal Pollution and Ecological Risk Assessment of Cultivated Land Soil in the Farming Areas of Coastal China:A Case Study of Donghai County,Jiangsu Province

Classical statistics,Inverse Distance Weighted and Hakasnson potential ecological index were used to study the distribution characteristics of 8 kinds of heavy metals( Cr,Ni,Cu,Zn,As,Cd,Pb and Hg) as well as their potential ecological risks in the topsoil( 0-20 cm) of cultivated land in Donghai County,a typical agricultural area along the Southeast Coast of China.The results showed that the average content of heavy metals in the cultivated soil of Donghai County was not over the risk screening values set in the Environmental Quality Standard for Soils.However,it was worth noting that in some of the sampling points,the content of Cr exceeded the risk screening value,and the standard exceeding points accounted for 24.74% of the total.In addition,the average content of Cr,Ni,As,Cd,Pb and Hg exceeded the soil background values of Jiangsu Province,and values for Cd,Cr and Pb were more than 1.5 times of the soil background value of Jiangsu Province.The heavy metals were at the medium integrated potential ecological risk level,and the potential ecological risk indices were high in the east and low in the west,and distributed in interlaced island shape.The potential ecological risk indices of the plains in the east were higher than those of the central gentle slope area and the western hillock area.The potential ecological risk was at a high level in Niushan Town which was situated the county center and in some regions with high urbanization levels.

Deployment Reliability Test and Assessment for Landing Gear of Chang' E-3 Probe

Chang'E-3 probe incorporates four landing gears to assure the soft-landing,which are stowed while launching and deployed after separated from rocket. Deployment reliability is quite crucial for this mission. The deployment reliability test( DRT) method and assessment method were developed in this paper. Then DRT was conducted and the deployment reliability estimate of Chang'E-3probe was used to verify the proposed methods.

Land Eco-sensitivity Assessment of Ecological Cities Based on LUCC

Land eco-sensitivity assessment is an important method in analyzing regional eco-environmental safety. This article is based on the studies of land use and coverage change (LUCC) with the interpretation result from Landsat images. It analyzes the land use degree of Shangluo City and gives the land eco-sensitivity classification, which includes soil and water conservation, disaster prevention and eco-environmental protection. Then an improved classification model is taken through the gray model and the variation coefficient. By comparing sensitivity in each level of land use degree change, the ecological recovery mode in study area is analyzed. The results show: the land use degree in Shangluo City has been declining from 1990 to 2009, with large area converted form cropland to forest, environment becomes better; the sensitivities of zoning based on the index level shows the medium sensitive area was largest. According to the variation coefficient gives the more reasonable proportion, the zoning was improved based on uncertainties. Because of the least amount of land use degradation area was taken in high sensitive region, it is considered that the ecological construction model in study area was still worth discussing. The healthy ecological development mode is proposed that low sensitive region should be protected while high sensitive region should receive high attention, so as to further improve the regional ecological security and improve the living environment efficiently.

Risk Assessment of Land Subsidence in Kathmandu Valley, Nepal, Using Remote Sensing and GIS

Land subsidence is identified as a global problem and intensive studies are being conducted worldwide to detect and monitor risk of this problem. Risk assessment of land subsidence is simply an evaluation of the probability and frequency of occurrence of land subsidence, exposure of people and property to the subsidence and consequence of that exposure. Remote sensing technology was used to extract information of land subsidence in Kathmandu Valley, Nepal. Also, Disaster Risk Index method and Analytic Hierarchy Process (AHP) along with Geographic Information System (GIS) tools were used to assess risk of land subsidence in Kathmandu Valley, Nepal. Subsidence volume for locations Central Kathmandu, Chauni, Lalitpur, Imadol, Thimi, Madhyaour Thimi, New Baneshwor, Koteshwor and Gothatar was calculated using a simple mathematical formula. The subsidence depth for these locations was found to be in a range of 1 cm to 17 cm and the maximum subsidence velocity was found to be 4.8 cm/yr. This study revealed that the location where maximum subsidence was observed (i.e. Central Kathmandu and Lalitpur) was found to be at high risk of experiencing land subsidence induced damage. Other location where subsidence was observed was found to be at medium risk and the rest of the Kathmandu valley was found to be at low risk with current data situation. This study can be considered as the first step towards other comprehensive study relating to land subsidence risk assessment. The outcome of this research provides a basic understanding of the current situation that can further assist in developing prevention and risk management techniques.

An Agricultural Land Resource Assessment Study Based on GIS-An Example from Guiyang City

This paper assesses the agricultural land resources of Guiyang City by means of GIS, on the basis of the pressure-state-response model in which soil heavy metal contamination is selected as a pressure indicator. The results suggest that most of the agricultural land resources are of good quality. However, there are 17.11 km\+2 dry land and paddy field, which belong to the region of serious heavy metal contamination and are not fit for planting crops. At the same time, the high quality plowland, which is suitable for cultivation, has decreased nearly by 1/3 due to soil heavy metal contamination. These findings may improve our understanding that it is very important to prevent and cure heavy metal contamination of Guiyang City.

Assessment of Ecological Risk to Land Use in Liaoning Province Based on Climate Change

Based on the climatic data and other statistics of climatic data of 54 meteorological stations from 1956 to 2005 in Liangning Province,the annual and seasonal light,heat and water and the like major elements of climatic resources are diagnosed and analyzed by using the method of linear climate trend rate. The results show that warming trend is 0.25 ℃/10 a,the precipitation decrease gradually by 2.2 mm/a and the decreasing trend of solar radiation and hours of sunshine is not dramatic. The overall climate change trend is warming and drying,featuring "significantly increased temperature,the decreased precipitation and sunshine". These features are significant in autumn,thus leading to the trend of moving west and retreating east of the phenology boundaries. The results of scenario analysis on ecological security show that the ecological risk is spreading rapidly from the northwest to the east and to the south and form the southeastern and southern coastal line to the inland;different ecological land-use system have different ecological fragility. Specifically,the bare land and low coverage grassland have highest ecological vulnerability,while the forest and paddy filed have lowest ecological vulnerability. Therefore,suggestions on the ecological land use are put forward in terms of maintaining the overall ecological land use balance,saving water and adapting to climate change.

A Study on the Theory and Approach of Environmental Impact Assessment in General Land Use Planning

In this paper,the theory and approach of environmental impact assessment in general land use planning are studied from different aspects.First,starting from the content and concept of general land use planning,the necessity of environmental impact assessment in general land use planning is illustrated.On the basis of its evaluation theories and methodologies,it attempts to establish index system of environmental impact assessment in general land use planning,and point outs that current general land use planning requires public participation.

An Assessment Tool for Land Reuse with Artificial Intelligence Method

This paper focuses on land resource consumption due to urban sprawl. Special attention is given to shrinking regions, characterized by economic decline, demographic change, and high unemployment rates. In these regions, vast terrain is abandoned and falls derelict. A geographic information system （GIS） based multi-criteria decision tool is introduced to determine the reuse potential of derelict terrain, to investigate the possible reuse options （housing, business and trade, industry, services, tourism and leisure, and re-greening）, and to visualize the best reuse options for groups of sites on a regional scale. Achievement functions for attribute data are presented to assess the best reuse options based on a multi-attribute technique. The assessment tool developed is applied to a model region in Germany. The application of the assessment tool enables communities to become aware of their resources of derelict land and their reuse potential.

Survey and Assessment of Land Ecological Quality in Cixi City

Soil,atmosphere,water and quality of agricultural product constitute the content of land ecological quality.Cixi City,through survey pilot project of basic farmland quality,carried out high precision soil geochemical survey and survey of agricultural products,irrigation water and air quality,and established ecological quality evaluation model of land.Based on the evaluation of soil geochemical quality,we conducted comprehensive quality assessment of atmosphere,water,agricultural products,and assessed the ecological quality of agricultural land in Cixi City.The evaluation results show that the ecological quality of most agricultural land in Cixi City is excellent,and there is ecological risk only in some local areas such as urban periphery.The experimental results provide demonstration and basis for the fine management of basic farmland and ecological protection.

Assessment and Potential Survey of Lands in Khuzestan Province Using the Buckley Geometric Mean Model and Geographic Information System (GIS)

Today environmental assessment is considered and used as the basis and foundation of any kind of human activity. This is the science which gives human the consciousness about abilities and disabilities of his surroundings. This study tried to assess and provide the potential survey of lands in Khuzestan province for agricultural activities by taking into account the climatic elements and displaying different elements in different seasons. To achieve this goal, first produced data were analyzed in GIS software and then the data was tested by professors and experts of department of soil science and was weighted using the Buckley geometric mean model. Finally, the obtained weights were applied in the software and the obtained results are as follow: except some east parts of Khuzestan province which have proper climate for agricultural activities, other regions are not in good conditions and it is necessary to use cultivation with low water requirements and high resistance to heat and sunlight in these areas.

Vulnerability Analysis of Land Instability Using Multi-Criteria Evaluation for Urban Sustainability: Methodological Overview and Case Study Assessment

There were many developed urban areas have been established without well studied from the hazards perspective. However, Mokattam Plateau is one of the most vulnerable areas of frequent landslides and rock-falls disasters (Moustafa et al., 1991). So, an integrated analysis method is highly needed. Spatial analysis of Multi-criteria evaluation (MCE) provided an assessment of the hazards’ factors (i.e. faults, joints, lithology, slope, old wadies/surface drainage, and quarries) at Mokattam area. The data have been analyzed by the MCE, Analytical Hierarchy Process (AHP)/Ordered Weighted Average (OWA)/Weighted Linear Combination (WLC). The research found that the geological factors (faults, joints, and lithology) were the highest contributors by about 65% of the hazardous driving forces, while the geomorphological processes (slope and old wadies/surface drainage) were contributed by about 30%. In addition, the impact of the human activities such as random urbanization, excess use of irrigation water and the transportation are critical hidden drivers that affect the land instability and accelerates the landslides and rock-falls (Amasha, 2009). Therefore, the decision makers and urban planners have to consider the four scenarios of low risk-high tradeoff (MIDAND), and high risk-some tradeoff (MIDOR) in their disaster risk management plans. While the risk-taking (OR) option is highly recommended for the new urban development projects to ensure the sustainability and risk resilience. While the risk-averse (AND) scenario is not recommended.

Assessing Change of Lamto Reserve Area Based on the MODIS Time Series Data and Bioclimatic Factors Using BFAST Algorithms

Lamto Reserve area is a savannah landscape threatened by periodic drought, and anthropogenic activities leading to natural ecological imbalance. The ecological support services of the landscape had been significantly impacted by the grassland ecosystem. The Breaks for Additive Season and Trend Algorithms have been implemented in R to analyze the land cover/land use dynamic in relation to the climatic driver of Lamto forest from 2000 to 2020. We examine the vegetation state breaks using vegetation phenological patterns, and several time series including the Normalized Difference Vegetation Index and the Enhanced Vegetation Index, were studied utilizing Breaks for Additive Season and Trend. The findings indicate that the phenological changes in the vegetation in 2020 resulted from an increased temperature from (27.7°C) to (32.17°C), and a decrease in precipitation (71.75 millimeters). The analysis of variance ANOVA of the non-parametric Mann-Kendall test reveals a strong correlation between Precipitation/Evapotranspiration Grass (p mperature/Evapotranspiration Grass (p < 0.311), and Temperature/Normalized Difference Vegetation Index (p in vegetation detected by the Breaks for Additive Season and Trend Algorithms were caused by temperature extremes and reduced rainfall.