Evaluation and Driving Force Analysis of Cultivated Land Quality in Black Soil Region of Northeast China

Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this study,320 counties in the black soil region of Northeast China(BSRNC)represent the research units used to construct the CQE system measuring the soil properties(SP),cultivated land productivity(CLP),ecological environment(EE)and social economy(SE).The total of 19 factors were selected to calculate the integrated fertility index(IFI)and divided into grades.Simultaneously,we used the coupling coordination degree model to comprehensively analyze the spatial pattern of the cultivated land quality(CLQ)in the BSRNC,and use the structural equation model(SEM)to analyze the driving mechanism.The results show the following:1)The CLQ of 262 counties in the BSRNC is in a state of coupling and coordination,and the coupling and coordination degree presents a spatial distribution pattern of‘high in the southwest and northeast,low in the northwest and southeast’.The coordinated development degree of 271 counties is between 0.4 and 0.6,which is in a transitional state between coordination and disorder.2)The CLQ in the BSRNC is generally good,with an average grade of 3.High-quality cultivated land accounts for 58.45%of all counties,middle-and upper-quality cultivated land accounts for 27.05%,and poor-quality cultivated land accounts for 14.49%.3)The SEM analysis shows that the SP,CLP,EE,and SE all influence the CLQ.Among them,the SP has the largest driving force on the CLQ,while the SE has the smallest driving force on it.The results confirm that the main factors affecting the evaluation results are crop productivity level,normalized difference vegetation index,ratio vegetation index,difference vegetation index,and organic carbon content.When implementing protection measures in counties with a low CLQ,considering a balanced coordination of multiple systems and reasonably controlling the quality degradation are important.This study provides the current situation and driving factors of the CLQ in the BSRNC and will play an important role in black soil governance and utilization.

Spatial-temporal Evolution and Driving Force of Cultivated Land Quality in Henan Province

The purpose of this study was to find out the spatial-temporal rules and driving force of cultivated land quality in Henan Province in the last ten years. Agricultural land grading factor evaluation was used to evaluate the cultivated land quality of 2002 and 2012 in Henan Province, and to research the change laws. Method of correlation coefficient was employed to select the driving forces affecting cultivated land quality evolution. The results indicated that the cultivated land quality in Henan Province increased slightly in the last ten years in general, and in spatial there were unchanged regions, increased regions and decreased regions. The cultivated land quality in spatial presented the trend of good becoming better, bad becoming worse, which should be highly valued in cultivated land quality protection and management. Land development and consolidation projects had significant contributions to increasing the cultivated land quality. Driving forces between the sudden change regions and gradual change regions were significantly different. The paper concluded that the research on the spatial-temporal evolution and driving force of cultivated land quality based on cultivated land quality evolution had important academic significance and practical value.

Arrangement of High-standard Basic Farmland Construction Based on Village-region Cultivated Land Quality Uniformity

As an important constitute of land consolidation, high-standard basic farmland construction is an important means to protect the quantity, quality and ecological environment of cultivated land. Its target not only lies in the increase of cultivated land quantity, but also the improvement of cultivated land quality, agricultural production conditions and ecosystem environments. In the present study, the quality evaluation method and construction arrangement of cultivated land were explored to facilitate the process of decision-making and implementation for high-standard basic farmland construction(HSBFC) with administrative village as the unit. Taking the land comprehensive improvement project area in Quzhou County, Handan City, Hebei Province as a case study, the whole process of the study comprised of three steps: 1) establishment of the evaluation model of cultivated land quality uniformity based on regional optimum cultivated land quality, and construction of the uniformity evaluation index system from the aspects of soil fertility quality, engineering quality, spatial quality and eco-environment quality, according to the new concept of cultivated land quality; 2) calculation of cultivated land quality uniformity by grading indicators, assigning scores and weighting sums, exploring the local homogenization characteristics of regional cultivated land quality through spatial autocorrelation analysis, and analyzing the constraints and transformative potential of barrier factors; 3) arrangement of HSBFC according to the principle of concentration, continuity and priority to the easy operation. The results revealed that the value of farmland quality uniformity for the administrative villages in the study area was between 7.76 and 21.96, and there was a difference between various administrative villages. The regional spatial autocorrelation patterns included High-High(HH), Low-Low(LL), High-Low(HL) and Low-High(LH). These indicate that regional cultivated land quality has local homogenization characteristics. The most restrictive factors in the study area were the medium and low transformation difficulty indexes, including soil organic matter content, farmland shelterbelt network density, field regularity and scale of the field. In addition, there were also high transformation difficulty indicators in some areas, such as sectional configuration. The project area was divided into four partitions: major construction area, secondary construction area, general construction area, and conditional construction area. The cultivated land area of each subarea was 1538.85 ha, 1224.27 ha, 555.93 ha, and 1666.63 ha, respectively. This comprised of 30.87%, 24.56%, 11.15% and 33.42% of the total project area, respectively. The evaluation model and index system could satisfy the evaluation of farmland quality and diagnosis of obstacle factors to facilitate the subsequent construction decision. The present study provides reference for the practice of regional HSBFC, and a new feasible idea and method for related studies.

Update of Cultivated Land Quality Grade Based on GIS—A Case Study of a County in Guangxi

The quality of cultivated land has an important influence on agricultural output, food security, sustainable development and the ability of using cultivated land resources. As the trend of cultivated land quality is getting more and more attention, in order to strengthen the management of cultivated land quality, improve the precision of cultivated land quality and other achievements, and maintain the current situation of cultivated land quality and other achievements. For this paper, taking A county of Guangxi Zhuang Autonomous Region as an example, with the support of GIS, the paper studies the grade and grade renewal of cultivated land by using the superposition method, studies the grade and grade change of regional cultivated land and its spatial distribution, grasps the status quo change of cultivated land and the grade and grade change of cultivated land caused by the quality construction of cultivated land in the year, and then provides scientific data for land use plan, land consolidation and cultivates land protection.

Improvement of Evaluation Methods for Cultivated Land Quality

As the existing cultivated land quality evaluation index system is unable to accurately evaluate the quality of cultivated land after land remediation,a modified land use coefficient method was established in this study to calculate the land use coefficient of cultivated land after land remediation. An evaluation index system was first established for the land utilization level of cultivated land in the remediation areas.After that,the land utilization level index before and after the remediation was evaluated separately. The ratio of the two was used as the correction factor to correct the original land use coefficient. The corrected land use coefficient was used to evaluate the quality of cultivated land. The quality evaluation and verification of the land remediation areas in Yuzhou City were conducted. It was found that the land use coefficient corrected by the modified method was more consistent with that calculated by production method 5 years after the project acceptance. It suggests that the modified land use coefficient method reflects the impact of land remediation on the quality of cultivated land,and it is more suitable compared with the production method for the quality evaluation of cultivation land in remediation areas.

Progress in Researches on Evaluation of Quality of Cultivated Land Consolidated from Coal Mining Subsided Land

The evaluation of consolidated cultivated land quality can provide basic information for how to perfect the program of land consolidation,as well as a reference for the dynamic monitoring of farmland quality in mining area. Based on the consultation and analysis of related literature,we can conclude that: firstly,most scholars focus on soil consolidation,while consider little about land use and economic condition. Secondly,foreign scholars usually use crop yields to judge the success of land consolidation,while domestic scholars have been evaluated the quality of consolidated cultivated land synthetically from several aspects,such as soil fertility,soil environmental quality,and farmland infrastructure conditions. Specifically,most of the evaluations are static,and indicators are different. Besides,the quality of consolidated cultivated land is generally low,and it lacks systematic research on technologies for improving quality of cultivated land consolidated from coal mining subsided land. It is concluded that future researches should focus on establishing scientific and feasible evaluation system to realize comparison of quality change in the dynamic course of " undisturbed-subsided-consolidated" cultivated land in coal mining areas,as well as technologies for improving quality of cultivated land consolidated from coal mining subsided land.

Research on Monitoring Area Division of Quality Grade Changes in County Cultivated Land and Technology of Deploying Monitoring Point

It is an important means in management of improving both the quality and quantity of cultivated land to monitor grade changes in cultivated land quality. How to deploy monitoring network system and its point reasonably and roundly are the key to the technology of monitoring grade changes in cultivated land quality by monitoring grade changes in cultivated land quality dynamically in order to obtain the information to the index of cultivated land quality and its changes based on the existing achievements of farmland classification and grading. Spatial analysis method is used to demarcate monitoring area and deploy monitoring point according to ARCGIS,of which the result can meet the demand for monitoring grade changes in cultivated land.

Current Situation of Cultivated Land Quality in Tongnan District of Chongqing City and Suggestions on Countermeasures

In 2015, the area of first and second class land in Tongnan Distdct of Chongqing was 221.646 km2, accounting for 30% of the total cultivated area, and the area of the third, fourth and fifth class land was 517.861 km2, accounting for 70% of the total cultivated area. The quality of cultivated land was at a low level. Comparison with the Second Soil Census in 2015 showed that the soil pH value has been improved; the organic matter content in the tillage layer showed a slight upward trend; the contents of available nitrogen, available phosphorus and available potassium in the topsoil increased. Countermeasures were proposed as follows： vig- orously promote the construction of high-standard farmland; adjust the industrial structure of agriculture and implement farming reform; combine organic and inorgan- ic fertilization to reduce the amount of fertilizers; popularize soil testing and formu- lated fertilization to change farmers＇ traditional fertilization habits; improve pollution control to ensure the sustainable productivity of farmland; strictly promote the quality management of cultivated land and strengthen the construction of quality monitoring system; increase investment and improve the monitoring mechanism; vigorously publicize and enhance the awareness of all citizens in protecting cultivated land; im- prove the law of cultivated land protection and enhance the seriousness of the law on the protection of cultivated land.

Early Warning of Cultivated Land Quality Based on Multiple Indicators

At present,the quality protection and early warning of cultivated land in China are actually based on the increase and decrease of the quantity of cultivated land and the change of its quality.The early warning of cultivated land quality based on this is easy to cause the problem of missing and wrong alarm.Based on the quality and productivity change of regional cultivated land,early warning on the regional cultivated land quality is conducted in this study respectively,and the results of the two early warning are compared.Moreover,a multi-indicator cultivated land quality early warning based on the quality change,productivity change and auxiliary indicators is proposed.The results show that:early warning of cultivated land quality based on quality and productivity change of cultivated land has certain limitations.Based on multi-indicator early warning,the number of counties with heavy,medium and light warnings in Henan Province is 52,8 and 11 respectively.The multi-indicator early warning result of cultivated land quality is more accurate,which can provide a basis for cultivated land protection and management assessment,and has great application value.

Study on Division Method of Quality Monitoring Control Area Based on Comprehensive Cultivated Land Attribute

The quality change of cultivated land resources requires the scientific deployment of monitoring areas.In this study,Yuzhou City is taken as an example to divide the quality monitoring control areas through the study of natural quality,utilization level,income level,and utilization characteristics,etc.Compared with the traditional administrative unit division or cultivated land quality division method,the regional homogeneity of this study is stronger,and there are quality differences between regions.It provides precondition and precision guarantee for the monitoring of cultivated land quality.

Research on Dynamic Change of Regional Cultivated Land Quality and Its Influence Factors

According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quality of cultivated land in Zhengzhou City. The results show that(1) the quality of cultivated land in Zhengzhou City has slightly increased during the study period. Due to the decrease in the amount of cultivated land,the production capacity has declined.(2) The impact of different types of cultivated land change on the quality of regional cultivated land is in the order of gradual change> decrease > increase > land construction project.(3) Zhengzhou City is able to maintain the quality of regional cultivated land through new cultivated land and project construction,but fails to maintain the production capacity. By analyzing the mechanism of regional cultivated land quality change in different types,the relationship between quality changes in various types of areas and overall quality changes could be analyzed,and it could provide policy recommendations for managers to formulate farmland quality and capacity protection,with significant application value.

Analysis on the Application of Quality Classification of Cultivated Land Resources in Municipal Land Space Planning:A Case Study of Chongzuo City

Cultivated land is the most important strategic resource to ensure food security.The newly constructed quality classification system of cultivated land resources considers the cultivated land health index for the first time.How the new classification and grading index system and the quality classification results of cultivated land resources to effectively guide the preparation of municipal land space planning has become a key research direction.This paper expounds the overall design idea for quality classification of cultivated land resources and classification index system.Taking Chongzuo City as an example,through the analysis of the quality classification results of cultivated land resources in the study area,using GIS spatial analysis and factor pairwise comparison method,this paper explores the application ideas and methods of quality classification research results of cultivated land resources in the formulation of cultivated land retention target,the delineation of dominant areas of cultivated land protection,the delineation of three control lines,the comprehensive improvement of land,and ecological restoration zoning in the municipal land space planning.

Exploring differentiated improvement strategies of cultivated land quality in China

Quality is the core feature of cultivated land. In the face of deteriorating cultivated land quality and growing food demand, improving cultivated land quality is a top priority for guaranteeing the sustainable use of resources and national food security. Cultivated land quality in the new era can be considered in four dimensions: suitability, contiguity, resistance and ecological stress. Cultivated land suitability in China shows a decreasing trend from east to west, cultivated land contiguity is high in the north-east and low in the south-west. In terms of cultivated land resistance, the number of strongly and weakly resistant cropping fields is small and spatially clustered. Cultivated land with ecological stress is mainly located in the northern region. Based on the current situation of cultivated land quality and the strategic needs of national high-quality development, China's future goals for improving cultivated land quality include four aspects: promoting the sustainable use of resources,improving the economic benefits of farming, coping with extreme meteorological disasters and meeting the transition of the food system.Against the backdrop of a volatile international environment and high domestic demand for food, China should guarantee a safe supply of staples, a stable supply of animal feed and a moderate supply of high-nutrient food. In the future, China should create three major food production spaces: highstandard, low-to medium-yield, and marginal cultivated land. China urgently needs to construct three paths to implement the goal of improving cultivated land quality, namely the development of high-standard cultivated land with the core of spatial optimization, resilience enhancement and scale coupling,the transformation of low-to medium-yield cultivated land with the core of obstacle elimination, tenure adjustment, ecological sustainable, and the conservation development of marginal cultivated land with a focus on sustainable use.

Design of Trinity Framework for Cultivated Land Protection

Starting with the goals and tasks of quantity,quality and ecological protection in different scales,this paper constructs a"trinity"framework of cultivated land protection system,and puts forward the key points of cultivated land protection in different scales.Finally,a preliminary evaluation is made on the quantity,quality and ecological protection of cultivated land on a macro scale in China.

County scale spatial differential characteristics of cultivated land use grade: A case of Binchuan County

Land resource is the material foundation of human survival and economic development, and the cultivated land is the essence of land resources. This paper takes the county scale, by using the method of GIS spatial analysis and statistical analysis unifies, to explore the quality of cultivated land in Binchuan County using level, and explain the utilization level of county cultivated land quality spatial differentiation characteristics. The results showed that:(1) in the quantity of cultivated land quality and utilization level, the average utilization of paddy land was greater than that of dry land, and the comprehensive utilization of cultivated land and so on. Among them, the paddy land ranged from grade 6 to 15, the average utilization was grade 11.6; dry land ranged from grade 2 to 11, the average utilization was grade 5.9; comprehensive range of cultivated land is grade 2 to 15, the average utilization was grade 8.1;(2) the quality of cultivated land utilization spatial differentiation. Paddy field, dry land and cultivated land and large value distribution in the central and southern, inverted V shape distribution; the smaller the value distribution in the East and West, a dumbbell shaped distribution. Among them, they don't use a larger value of paddy land distributed in the central, South and southwest, the maximum value is 14.3, the smaller the value distribution in the West and East, the minimum value is grade 7; the larger the value distribution by the dry land in the South and West, the maximum value is grade 10.2, the smaller the value distribution in the West and East. The minimum value is grade 2.3; the comprehensive utilization of cultivated land don't distributed larger value in the central, South and south-west, the maximum value is grade 12.7, the smaller the value distribution in the West and East, the minimum value is grade 3.5. This paper can provide scientific basis for the dynamic monitoring of cultivated land quality, the transformation of low yield farmland and the early warning of cultivated land pressure.

Research on Grade Renewing of Cultivated Land at County Level:A Case Study of Daxing District,Beijing

To create a scientific way to renew the grades of cultivated land at county level, monitoring points were set up according to the monitoring control regions and grade types of cultivated land in Daxing District, Beijing, and soil samples were collected to carry out chemical analysis. Afterwards, the input and output data of cultivated land in each village were surveyed to renew the grades of cultivated land. The results indicate that the average natural grade of cultivated land was 8.4, which was equal to that of 2004; the average utilization grade was 8.1, which was slightly higher than that of 2004; the average economic grade was 9.9, which was lower than that of 2004. It is concluded that it is scientific to renew cultivated land grades through scientifically setting monitoring points according to the monitoring control regions and grade types of cultivated land.

Shifting cultivation effects on creek water quality around Barkal Upazila in Chittagong Hill Tracts,Bangladesh

Abstract： We report the effects of shifting cultivation on water quality in 16 creeks investigated once in 2007 and twice in 2008 in 16 apparently similar small neighboring watersheds, each of 3 to 5 ha, at four locations around Barkal sub-district under Rangamati District of Chittagong Hill Tracts in Bangladesh. Concentrations of 5042- and K＋, and pH in creek water were lower, and NO3-N and Na＋ concentrations were higher in shifting-cultivation land compared to land with either plantation or natu- ral forest or a combination of these cover types. Shifting cultivation effects on some water quality parameters were not significant due to change in land cover of the watershed between two sampling periods either through introduction of planted tree species or naturally regenerated vegetation. Conductivity and concentrations of HCO3- PO43-, Ca2-- and Mg2＋ in creek water showed no definite trend between shifting cultivation and the other land cover types. At one area near the Forest Range Office of Barkal, creek water pH was 5.8 under land cover with a com- bination of shifting cultivation and plantation. At this area Na~ concentra- tion in shitting-cultivation land ranged from 32.33 to 33.00 mg-L＂ and in vegetated area from 25.00 to 30.50 mg.L-1 in 2007. At another area, Chaliatali Chara, SO42 concentration in a shifting-cultivation watershed ranged from 4.46 to 10.51 mg-L-1, lower than in a vegetated watershed that ranged from 11.69 to 19.98 mg.L-1 in 2007. S042-concentration in this shifting-cultivation area ranged from 1.28 to 1.37 mg.L^-1 and in the vegetated area from 1.37 to 3.50 mg-L^-1 in 2008.

多样化种植对提升耕地质量的作用:进展与展望

多样化种植是现代生态农业的重要举措之一,对提高生物多样性、生态服务功能和土壤质量等具有重要意义。在全球粮食供给紧张和耕地短缺背景下,多样化种植在提升我国耕地质量和保障粮食安全中将会发挥越来越重要的作用。但现有研究对多样化种植的理解多集中在提高生物多样性和发挥生态功能等方面,对其提升耕地质量的作用关注较少,特别是多样化种植如何通过改善土壤物理、化学、生物多样性来提高耕地质量和维持土壤健康方面的理解还较为局限。本文在总结多样化种植的内涵及对促进耕地土壤健康和提高生态服务功能作用的基础上,系统梳理了多样化种植对改善土壤物理、化学、生物多样性等方面的作用研究进展,展望了未来以提升耕地质量为核心发展多样化种植亟需关注的方向和研究重点,以期为多样化种植在我国耕地质量提升策略中发挥更大作用提供参考。

东北黑土区典型县域耕地质量对耕地水田化的空间响应

[目的]耕地水田化过程对耕地质量具有至关重要的影响,明确东北黑土区耕地质量对耕地水田化的空间响应,是提升黑土耕地质量实现耕地可持续利用的重要前提。[方法]构建LESA耕地质量评价体系,采用CRITIC模型、双变量局部空间自相关模型,揭示耕地质量和耕地利用变化之间的空间响应关系。[结果](1)研究区耕地水田化现象剧烈,呈现出东部最强、西部次之、中部最弱的时空分异格局;(2)研究区耕地质量变化显著,耕地质量下降比例低于质量提升比例,表现出中部下降最高、西部下降次高、东部下降最低的时空格局;(3)研究区耕地质量对水田化的响应具有双重效应,负向响应更为敏感,整体呈现出东部耕地质量响应程度高于其他区域的空间格局。[结论]研究区耕地水田化对耕地质量具有正、负两种效应,依据效应方向进行耕地利用结构调整,是保护黑土耕地的重要途径。对于具有正向效应的区域应适度推进旱改水项目,而针对具有负向效应的区域应停止旱改水工程,积极进行水田休耕,并可适当地将其恢复为旱地。

三亚市耕地质量等级年度变更评价及质量提升

开展耕地质量等级评价,可建立健全耕地质量等级调查评价与信息发布制度,并准确掌握区域尺度的耕地质量现状及变化趋势,查清影响耕地生产的主要障碍因素,有针对性提出加强耕地质量保护与提升的对策措施与建议,进而提升耕地质量管理水平。以三亚市耕地为对象,开展耕地质量等级年度变更评价。结果表明,全市耕地质量平均等级为5.23,其中高等级地(一级地至三级地)占全市耕地面积的23.52%,中等级地(四级地至六级地)占49.12%,低等级地(七级地至十级地)占27.36%;三亚市耕地的主要障碍因素为障碍层次和渍潜,分别对其提出了改良措施及建议。