Analysis of Dry-Wet Climate Change Characteristics and Main Influencing Factors in Main Grain Producing Area of Tibet from 1980 to 2021

Based on the daily meteorological observation data of seven meteorological stations in southern Tibet from 1980 to 2021 (April-October), the temporal and spatial variation characteristics and influencing factors of aridity index ( AI ) in the growing season of major grain producing areas in Tibet were studied by using climate tendency rate, Mann-Kendal test, Morlet wavelet analysis, GIS hybrid interpolation method, Pearson correlation coefficient, contribution rate analysis and other methods. The results showed that the average AI in the main grain producing areas of Tibet was 1.7, which belonged to the semi-arid area, and the overall trend was decreasing (humidifying) (-0.036/10 a). The linear decreasing trend was different in different regions, and the area around Lhatse County was the most significant (-0.26/10 a). AI had no obvious abrupt change, and had long- and medium-term fluctuation characteristics of 24 years, 6 years. The spatial distribution was uneven, and had the characteristics of ‘shrinking arid area and expanding humid area . The contribution rates of the main climate influencing factors of AI varied in different regions. In general, the contribution rates after quantification was as follows: precipitation (34.9%)>relative humidity (28.4%)>sunshine (19.9%)>maximum temperature (12.4%).

Variation Character of Grain Yield per Unit Area in Main Grain-producing Area of Northeast China

Based on the surveys and the statistic data during 1980-2003, the variation character of grain yield per unit area in Northeast China and its main factors have been discussed by the methods of statistics and grey correlation analysis. The results show that: 1) the grain yield per unit area has been taking on an increasing trend in the recent 20 years. It increased from 2519.80kg/ha in 1980 to 4216.11kg/ha in 2003, with an increasing rate of 67.32%; 2) the variation of grain yield per unit area is considerably prominent and its range is also very great, with the maximal increase rate of 42.59% and maximal decrease rate of 21.13%, respectively, which are far above the whole Chinese average level; 3) the variation of main crops' yield per unit area is remarkable, which takes on the character that the yield of corn is much higher than that of soybean and rice; and 4) the grey correlation analysis shows that the most important factors impacting the variation of grain yield per unit area are the total power of agricultural machinery, the consumption of chemical fertilizer and effective irrigated area. However, the influence of natural disaster and income level should not be ignored. Effective ways to improve grain yield per unit area are to construct farmland improvement groundwork, reclaim the middle- and low-yield farmland, etc.

FUZZY COMPREHENSIVE EVALUATION OF CONTAINER TRANSPORTATION MODES ALONG THE CHANGJIANG RIVER MAIN LINE AND ITS DELTA AREA

The Changjiang River (Yangtze) is one of the fastest growth areas of container transportation in China. Rail, road and water transportation have competed against each other for container transportation in the Chang-jiang River main line and its delta area. It is of significance to assess these different transportation modes scientifically in order to organize container transportation efficiently in this area and make decision for integral plan and construction of transportation system in this area. This paper outlines application of fuzzy comprehensive evaluation to appraise different modes of typical direction of containers. Twelve assessment indexes were decided. Membership functions were formulated. Evaluation results indicated that road transportation was optimal mode in the Changjiang River delta area, however water transportation was the primary way in the Changjiang River main line.

Accumulation and risk assessment of heavy metals in dust in main living areas of Guiyang City, Southwest China

Guiyang is a famous tourist city located in southwestern China. In this study, dust from eleven residential areas, seven city squares, and nine schools was collected to measure the heavy metal levels and evaluate its risk. At each sampling site, 4–5 sub-samples were taken as a bulk sample. All samples were air-dried, ground, passed through a 0.105 mm nylon sieve, digested with HNO3-HClO4 to determine the concentrations of Cd, Cu, Ni, Pb and Zn by ICP-MS, and digested with 1:1 aqua regia to determine As by AFS. The results show that the concentrations of As, Cd, Cu, Ni, Pb and Zn in dust of Guiyang City follow normal distribution with means of 16.1, 1.54, 138, 47.7, 129 and 479 mg/kg, respectively. Levels of As, Cd, Cu, Ni, Pb and Zn exceed the background level of soil in Guizhou Province by 33%, 96%, 100%, 78%, 96%, and 100%, respectively. Cd, Cu, Pb and Zn are heavily accumulated in dust of living areas with accumulation factors of 4.10, 5.12, 4.12 and 5.51, respectively. City square possesses the highest geometric means of As, Cd, Cu, Pb, and Zn. The risks of heavy metal exposure to teenagers are not obvious and in an order of As>Pb>Cu>Ni>Zn(Cd).

Interactive Effect and Spatial Characteristics of Agricultural Development Level and Transport Superiority Degree in Main Grain-producing Areas of the Central Jilin Province,China

To investigate the spatial synergy between agricultural development level and transport superiority degree in grain-producing areas of the central Jilin Province and the driving mechanism between them,22 counties in the central Jilin Province were used as the research units to calculate agricultural development level and transport superiority degree using the entropy weighting method,weighted travel time and raster cost distance.The spatial econometric model was used to analyze the mechanism of the mutual influence between the two.The main conclusions are as follows.1)Agricultural development level around Changchun,the provincial capital city,and in the areas of Changchun-Jilin and Changchun-Gongzhuling is high,whereas the development level of the counties in the southwest is low.2)Transport superiority degree of each county has improved,the overall connectivity of the road networks has been optimized,and the level of transportation accessibility has shown the development trend of‘centralization’,exhibiting the characteristics of proximity diffusion.3)Locally,there is spatial heterogeneity in the mutual driving effects of the two,with six main patterns.4)The theoretical conditions of von Thunen’s agricultural location have changed under the conditions of market economy due to the improvement of the transport networks,the new model of agricultural development,and the changes of the market system.

Increasing Subsidies to Main Grain Production Area——Necessity of the Rejuvenation of Northeast China

As an old industrial base, Northeast China is one of the most important grain production base. To rejuvenate Northeast China, it is necessary to strengthen farming products processing, lengthen industrial chain and develop sustainable agriculture.

Status Quo of Maker Spaces in Main Urban Area of Chengdu

This paper, based on the literature review and field investigation, studied the status quo of maker spaces in main urban district of Chengdu at a time when the development of the maker spaces has received strong support from national and local governments. In addition to introducing the related concepts and policy support of the maker space, it summarized its distribution characteristics, audience characteristics, and status quo as well as problems and presented the direction for the development of the maker space in main urban area of Chengdu grounded on a survey of the status quo of national maker spaces in main urban area of Chengdu.

Measurement of Grain Production Efficiency in Main Grain-producing Areas and Analysis of Inter-provincial Differences--A Study Based on Super-SBM Model and Malmquist Index

China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-producing areas has become the fundamental way to strengthen the grain production capacity and improve the national food security capability,and to improve the efficiency of grain production in major grain-producing areas requires empirical support.This paper used the Super SBM model and the Malmquist index to measure the grain production efficiency of the main grain-producing areas from 2001 to 2020 from both static and dynamic perspectives,and compared the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas.The results showed that from 2001 to 2020,the grain production in the main grain-producing areas was in a relatively ineffective state,and the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas were obvious.The order of grain production efficiency in different soil types was black soil region>red-yellow soil region>paddy soil region>fluvo-aquic soil region,and the order of grain production efficiency of the provinces(autonomous regions)in the main grain-producing areas was Jilin>Heilongjiang>Inner Mongolia>Jiangxi>Hunan>Sichuan>Hubei>Jiangsu>Liaoning>Henan>Anhui>Shandong>Hebei.From 2001 to 2020,the total factor productivity of grain in the main grain-producing areas increased,but due to the trade-off between the technological progress and the growth of technical efficiency,the increase in the total factor productivity of grain in the main grain-producing areas was small,and the growth mainly came from the increase of input factors in this period.The total factor productivity of grain in Hebei,Heilongjiang,Liaoning,Jilin,Inner Mongolia,Shandong,Jiangsu,Henan and Anhui increased,but the increase was small,while the total factor productivity of grain in Jiangxi,Sichuan,Hunan and Hubei provinces declined.

Reflections on Plain Greening in Coastal Urban Areas： A Case Study of Plain Greening in the Main Urban Area of Taizhou

The current situation,existing problems and characteristics of greening in the main urban area of Taizhou were analyzed,and the construction ideas and safeguard measures of plain greening in urban areas in the new era were put forward.

Use of the area of main influence to fix a relevant boundary for mining damages in Germany

In 2010, the fracking discussion in Germany caused a number of changes in German law, which came into force in 2016.Especially the production of gas had to be regulated.With the legislation amendment, the Subsidence-Area Mining Regulation has been revised, too.The changes expand the compensation of mining damages, especially to the extraction with drilling from the surface and underground storage.Although the Subsidence-Area Mining Regulation has been revised, the area of main influence(subsidence of 10 cm)remains to determine a relevant boundary for mining damages.The determination and prediction of this boundary above caverns are presented in this paper.In addition, further elements of ground movements and their relevance to mine damages are analyzed.The usage of the area of main influence to fix a relevant boundary for mining damages does not correspond to the relevant elements of ground movements.A limit for differences in subsidence(tilt) or horizontal changes in length should be preferred to describe the relevance of mining damages on buildings.Furthermore, this paper outlines the meaning of using the area of main influence to fix a relevant boundary for mining damages.

Industrial Policy Analysis of Restricted Development Zones in Western China——A Study of State-level Main Producing Areas of Agricultural Products and Key Ecological Functional Areas

As one of the important policies of promoting the formation of main functional areas, the industrial policy directly determines the sustainable growth of space control ability of main functional areas. A restricted development zone is a type of main functional area which provides agricultural products and ecological products, assures the supply of national agricultural products and the stability of ecosystems, as well as safeguards the ecological functions and agricultural functions of wider regions by restricting its own development. Therefore scientific, complete and operable industrial policy support is needed. Restricted development zones are distributed widely in western China. With the restriction of their main functions, differential industrial policies should be implemented in the development of the restricted development zones: Dealing well with the relationship between industrial development and ecological protection, developing special industries which are friendly to resources and environment and appropriate for local conditions, guiding and encouraging industries to learn from regions with favorable development conditions, orderly withdrawing industries and enterprises adverse to main functions, facilitating industrial structure upgrading, optimizing industrial organization, improving industrial technological level and rationalizing industrial layout.

Water Consumption and Use Efficiency of Main Crops on Semi-drought Area of Western Liaoning Province

The laws of water consumption in corn,peanuts and millet on the semi-drought area of western Liaoning Province were studied through the FAO-Penman Monteith method and the water balance method.Among three corps,the amount of the day water demand,the whole growth period water demand and the soil water deficit of corn were all the largest.At the same time,its degree of agreement between the water demand and the level of precipitation was the worst,and its average in crop coefficient was larger.The amount of th...

黄芩中国主产区栽培技术差异性调查分析

黄芩是常用的大宗药材,市场需求量大,为了解当前各产区黄芩栽培技术、管理水平、品质和产量的差异,对山西、陕西、甘肃、山东、河北、河南、内蒙古等我国黄芩主产区的生产现状进行调查,发现各主产区的生态环境、栽培方式、施肥技术、病虫害防治、采收加工等方面均存在一定差异。因此,建议当前应进行黄芩生态适宜性区分析及各产区适宜栽培技术研究,以便形成黄芩高产、优质、高效的栽培技术体系,进一步为黄芩栽培提质增效奠定基础。

健全我国粮食主产区利益补偿机制的新思路

粮食安全关乎国运民生,政府在战略上高度重视主产区利益补偿问题。当前,我国粮食产业面临产销区粮食供需矛盾加剧、经济发展差距加大、种粮收益不稳、主产区资源和环境压力激增等诸多压力与挑战,健全粮食主产区利益补偿机制、创新补偿思路是我国保障粮食安全亟待解决的现实难题。因此,在进一步拓展了粮食主产区利益补偿的理论基础上,提出利益补偿的新思路,要以公平、协调和可持续发展实现各区域的共同富裕为导向,形成多维度补偿机制。在纵向上,完善以政府为主导的利益补偿机制,提高补偿资金使用效能,在横向上,制定各区域责任分担机制,积极探索新型产销区协作关系,建立产销区横向利益补偿机制。此外,还要综合考虑主产区发展的显性和隐性损失,通过做好用地文章、提高产业核心竞争力、建立粮食生态补偿机制等途径弥补主产区经济发展的机会成本和粮食生产的资源消耗。

我国乡村老龄化现状及其对粮食生产的影响与应对

根据2020年最新人口普查数据,我国乡村老龄化率为17.72%,先于城市步入中度老龄化社会。我国乡村老龄化整体呈现出老年抚养比增速快、低龄老人务农比例高等特征,与国际主要发达国家相比我国乡村老龄人口就业占比相对较高。分区域看,粮食主产区乡村老龄化增幅更多、老年抚养比更重、老龄就业比重更高;全国乡村老年抚养比28.13%,但粮食主产省份达31.28%。通过定性梳理乡村老龄化对农户参与粮食种植及其粮食生产行为效率等的影响,提出积极应对乡村老龄化、保障粮食安全的思路与对策建议。

国家文化公园主体功能区识别路径构建——以长江国家文化公园湖北段为例的实证研究

国家文化公园是国家公园建设模式的重要创新,其主体功能区划定是落实总体建设要求、保障基础工程有效实施的重要基础,但目前仍存在识别路径、技术方法模糊不清的问题。尝试在解读主体功能区内涵的基础上,以系统耦合思维构建“文化生态双维度耦合-保护利用双象限评价-空间功能四分区重构”的主体功能区识别路径,对长江国家文化公园的湖北段进行实证研究。结果表明,主体功能区呈现出以提供基础条件的管控保护区为基底、以文化引领的主题展示区为核心、以文旅融合区和传统利用区为外延圈层的空间分布特征,与大运河国家文化公园主体功能区布局模式相符。期望在丰富国家文化公园理论研究的同时,助力长江国家文化公园的科学布局与规划编制。

渤海湾盆地东濮凹陷天然气成因及分布特征

针对东濮凹陷高热演化程度区天然气成因复杂,天然气富集规律及勘探潜力认识不清等问题,文中利用聚类分析、生烃模拟实验等手段,对天然气成因类型及分布特征进行了研究。研究结果表明:东濮凹陷存在油型气、煤成气及混合气3大类天然气。其中:油型气包括低熟油型气(Ro介于0.5%~1.2%)、中熟油型气(Ro介于1.2%~1.6%)和高熟油型气(Ro介于1.6%~2.0%),依次分布于构造顶部、斜坡带、洼陷带;煤成气Ro介于2.0%~3.0%,包括源外高熟煤成气和源内高熟煤成气;而混合气主要分布在高热演化烃源灶的大断裂周围。通过对主力生气区分析发现,油型气和煤成气对应的烃源岩主力生气深度分别介于4000~5000,5000~7000 m,空间上具有接力特征。东濮凹陷天然气富集程度与生烃洼陷的热演化程度关系密切,中、高热演化洼陷(Ro介于1.0%~3.0%)将是渤海湾盆地和东濮凹陷未来天然气勘探的重点领域。

兰州市主城区公共服务设施与居民需求匹配度分析

基于2022年兰州市主城区14类公共服务设施POI数据,采用核密度分析、加权叠加的空间分析方法,依据不同空间尺度的生活圈分析居民对公共服务设施需求度和现状设施完善度的匹配关系,研究结果表明:兰州市主城区公共服务设施呈现出东密西疏的带状分布特征,餐饮美食、购物消费、旅游景点等设施呈现出多中心聚集分布;部分区域居民需求度和设施完善度不匹配,主要是老旧小区修建时间早、人口密度大,存在居民需求度高但设施完善度低的情况;用地功能发生变化,如新建商圈周围设施相对完善,但居住小区较少,存在居民需求度低但设施完善度高的情况;可通过增设完善老旧小区周边设施、构建多中心公共服务设施聚集地等措施,促进各区生活服务水平趋向均等化发展。

优化国土空间发展格局视域下推进城市群一体化发展的空间逻辑

城市群是推动新型城镇化的主体形态和促进发展要素合理流动的空间载体,在支撑国民经济社会发展和提升国际竞争力方面发挥关键作用。优化国土空间发展格局蕴含引导要素优化配置的目标指向、提升空间结构韧性的实质内容、加快构建新发展格局的时代背景,为考察城市群一体化发展的空间逻辑提供有益视角。从宏观顶层设计、中观权力运作、微观主体行动来看,优化国土空间发展格局中的城市群一体化发展,涉及空间规划与发展规划协同引领、空间尺度与权力结构的动态适配、核心城市与重要主体的辐射带动。根据优化国土空间发展格局的价值导向与功能预期,新时期健全城市群一体化发展机制应规范完善空间规划程序、优化升级空间治理体系、渐进实现空间正义,逐步形成优势互补、均衡发展的城市群布局与国土空间体系。