New Rural Community Construction or Retention Development:A Comparative Analysis of Rural Settlement Transition Mechanism in Plain Agriculture Area of China Based on Actor Network Theory

It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical framework for the study of RST.Taking two typical villages with different transition paths in rural areas of North China Plain as examples,this paper reveals the mechanism of RST and makes a comparative analysis.The results show that:1)after identifying problems and obligatory passage point,key actors recruit heterogeneous actors into the actor network by entrusting them with common interests,and realize RST under the system operation.2)Rural settlements under different transition paths have similarities in the problems to be solved,collective actions and policy factors,but there are differences in the transition process,mechanism and effect.The actor network and mechanism of RST through the path of new rural community construction are more complex and the transition effect is more thorough.In contrast,the degree of RST of retention development path is limited if there is no resource and location advantage.3)Based on the applicable conditions of different paths,this paper designs a logical framework of‘Situation-Structure-Behavior-Result’to scientifically guide the identification of RST paths under the background of rural revitalization.

Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of Crop Residue Burned Areas:A Case Study of Songnen Plain,Northeast China

The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in China.Here we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast China as a case using satellite image of 2020.We employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)MCD64A1 burned area product.The overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TCQ and 51TYM cases,respectively.In comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TCQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 images.The balance of omission error and commission error was also improved.The integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination mechanism.This method exhibits excellent extensibility and flexibility taking the image tile as the operating unit.It is suitable for burned area detection at a regional scale and can also be implemented with other satellite data.

Driving Analysis on Ecological Security in Vulnerable Transition Areas of Mountain and Plain

[Objective] This study aimed to investigate the driving mechanism of eco- logical security in vulnerable areas in mountain and plain. [Method] The ecological security evaluation index system of Lincheng County was established using PSR model. Driving mechanism was analyzed in total system and subsystems respectively by the principal components. The ecological safety driving factor was calculated through the total system and subsystem respectively. And the intersection was adopt- ed as dominant driving factor. [Result] A total of 10 indices including density index of rivers, land degradation index, farmland drought and flood insurance yield, human in- terference index, population density, the natural population growth rate, per capita GDP, the R＆D funds spending accounts for the proportion of GDP, laborer by edu- cation degree and three industry accounted for the proportion of GDP, are the domi- nant driving factors of the regional ecological security. [Conclusion] This study will pro- vide reasonable and feasible advice for the benign development of the area.

Assessment of Groundwater Source of Piedmont Plain Area of China Northwest Arid Region Based On Numerical Modeling

After the middle of 1960s,along with the appearance and extensive utilization of computer featured in large capacity and rapid speed,numerical method(mainly include finite difference method and finite element

Numerical simulation of groundwater and early warnings from the simulated dynamic evolution trend in the plain area of Shenyang,Liaoning Province(P.R. China)

Groundwater level is the most direct factor reflecting whether groundwater is in a virtuous cycle. It is the most important benchmark for deciding whether a balance can be struck between groundwater discharge and recharge and whether groundwater exploitation will trigger problems pertinent to environment, ecology and environmental geology. According to the borehole and long-term monitoring wells data in the plain area of Shenyang, a numerical groundwater model is established and used to identify and verify the hydrogeological parameters and balanced items of groundwater. Then the concept of red line levels, the control levels of groundwater is proposed, the dynamic evolution trend of groundwater under different scenarios is analyzed and predicted and groundwater alerts are given when groundwater tables are not between the lower limit and the upper limit. Results indicated:(1) The results of identification and verification period fitted well, and the calculation accuracy of balanced items was high;(2) with the implementation of shutting wells, groundwater levels in urban areas of Shenyang would exceed the upper limit water level after 2020 and incur some secondary disasters;(3) under the recommended scenario of water resources allocation, early-warnings for groundwater tables outside the range would occur in the year of 2020, 2023, 2025 respectively for successive wet, normal and dry years. It was imperative to reopen some groundwater sources and enhance real-time supervision and early-warning to prevent the occurrence of potential problems.

Terrestrial water storage variation in Hebei plain area of China,based on ground surface gravimetry

Variation of terrestrial water storage in the Hebei plain area from March 2010 to June 2014 was studied using ground gravimetry combined with vertical displacement data from the Global Navigation Satellite System.Results show that observed gravity variation in this area increased continuously,basically reflecting a trend toward land subsidence.With the effect of this subsidence removed,a dominantnegative change in gravity variation was evident,reflecting an average rate of decrease in terrestrial water in this area of 0.10±0.053 m/y,and this is equivalent to a volume of 81.5±43.2×108 m^(3)and is consistent with the spatial distribution of groundwater change from measured hydrologic data.These results can be an essential reference and supplement for the study of terrestrial water variation in the Hebei plain area,and indicate that ground surface gravimetry can be used as an important mean for studying changes in terrestrial water.

Eco-environment contribution of agroforestry to agriculture development in the plain area of China—Huai'an Prefecture, Jiangsu Province as the case study area

For improving the environmental quality and ensuring supply of wood and non-timber forest products, many forests have been planted in plain areas of China. Scientists have studied their benefits, almost all of the approaches were based on fixed-point data, and few was considered on the non-efficient factors and temporal scale effects. This paper studies the positive and negative benefits at a large temporal scale, and the effects of plain afforestation on stockbreeding and rural economy. The benefits of plain afforestation, correlation coefficiency of agroforestry and production factors are analyzed via stochastic frontier modeling in Huanghuaihai Plain Area of China; elastic coefficient of agroforestry, husbandry, farming, and total output of agricultural sector are calculated through adopting partial differential equation. Some conclusions can be drawn that, plain forests have an important effect on the development of plain agriculture. But shelterbelts and small-scale forests have different effect on the development of agricultural economy. Shelterbelts have negative effect on the industries, but small-scale forest has positive effect. On the whole, contribution of forest resource to value of animal husbandry and gross production value of agriculture is positive, and to the value of farming is negative.

Hydrocarbon Accumulation Process in the Marine Strata in Jianghan Plain Area, Middle China

Marine strata in the Jianghan Plain area are widely distributed with a total depth of more than 8,000 m from the Upper Sinian to the Middle Triassic. Six reservoir caprock units, named Z-C2, C2-O, S, D--C, P and T1, can be identified with each epoch. The geology, stratigraphy, drilling, oil testing and other basic data as well as the measured inclusion and strontium isotope data in the study area are used in the analysis of the formation and evolution process of marine petroliferous reservoirs in the Jianghan Plain area. This study aims to provide a scientific basis for the further exploration of hydrocarbons in the Jianghan Plain and reduce the risks by analyzing the key factors for hydrocarbon accumulation in the marine strata. Our findings show that in the Lower Palaeozoic hydrocarbon reservoir, oil/gas migration and accumulation chiefly occurred in the early period of the Early Yanshanian, and the hydrocarbon reservoir was destroyed in the middle-late period of the Early Yanshanian. In the Lower Triassic-Carboniferous hydrocarbon reservoir, oil/gas migration and accumulation chiefly occurred in the Early Yanshanian, and the hydrocarbon reservoir suffered destruction from the Late Yanshanian to the Early Himalayanian. The preservation conditions of the marine strata in the Jianghan Plain area have been improved since the Late Himalayanian. However, because all source beds have missed the oil/gas generation fastigium and lost the capacity to generate secondary hydrocarbon, no reaccumulation of hydrocarbons can be detected in the study area＇s marine strata. No industrially exploitable oil/gas reservoir has been discovered in the marine strata of Jianghan Plain area since exploration began in 1958. This study confirms that petroliferous reservoirs in the marine strata have been completely destroyed, and that poor preservation conditions are the primary factor leading to unsuccessful hydrocarbon exploration. It is safely concluded that hydrocarbon exploration in the marine strata of the study area is quite risky.

Spacial organization on the rural settlements in plain areas—taking Pinghu city in Zhejiang of China as an example

This paper analyses the spacial distribution, quantity-scale, function-structure and facilities from the angle of spacial organizational optimizing theory and sustainable development thought. The authors point out the distributional principles of rural settlements in plain areas, and put forward planning and distribution of various levels of rural settlements (central villages, basic villages and natural villages).

Optimizing groundwater recharge plan in North China Plain to repair shallow groundwater depression zone, China

The North China Plain is one of the main grain producing areas in China. However, overexploitation has long been unsustainable since the water supply is mainly from groundwater. Since 2014,the South-to-North Water Diversion Project's central route has been charted to the integrated management of water supply and over-exploitation, which has alleviated the problem to a certain extent. Although the Ministry of Water Resources has made many efforts on groundwater recharge since 2018 most of which have been successful, the recharge has not yet been sufficiently focused on the repair of shallow groundwater depression zones. It still needs further optimization. This paper discusses this particular issue,proposes optimized recharge plan and provides the following recommendations:(1) Seven priority target areas are selected for groundwater recharge in alluvial and proluvial fans in the piedmont plain, and the storage capacity is estimated to be 181.00×10~8 m~3;(2) A recharge of 31.18×10~8 m~3/a is required by 2035 to achieve the repair target;(3) It is proposed to increase the recharge of Hutuo River, Dasha River and Tanghe River to 19.00×10~8 m~3/a and to rehabilitate Gaoliqing-Ningbailong Depression Zone;increase the recharge of Fuyang River, Zhanghe River and Anyang River to 7.05×10~8 m~3/a and rehabilitate Handan Feixiang-Guangping Depression Zone;increase the recharge of Luanhe River by 0.56×10~8 m~3/a and restore Tanghai Depression Zone and Luanan-Leting Depression Zone;moderately reduce the amount of water recharged to North Canal and Yongding River to prevent excessive rebound of groundwater;(4) Recharge through well is implemented on a pilot basis in areas of severe urban ground subsidence and coastal saltwater intrusion;(5) An early warning mechanism for groundwater quality risks in recharge areas is established to ensure the safety. The numerical groundwater flow model also proves reasonable groundwater level restoration in the depression zones by 2035.

Study on Farmers' Cognition and Willingness to Plant Trees during Collective Forest Right Reform Based on Data from Plain Areas of Henan Province

On the basis of the survey data from plain areas of Henan Province,farmers' cognition and willingness to plant trees in collective forest right reform are studied. According to statistical analysis and regression equation of binary logistic regress analysis,it is generally believed that different participants have various attitudes to the reform,with regard to if planting trees or more,reform variables have a distinct effect,as well as income variable and loaning or lending variable. At last,some advices are put forward,that is,the government should strengthen collective forest right reform,accelerate matching reform and increase policy and financial support to forestry farmers.

Analysis on Change Tendency of the Precipitation Resource during Growth Period of the Conventional Crops in Plain Area before Taihang Mountains

[Objective] The aim was to study change tendency of the precipitation resource during growth period of the conventional crops in plain area before Taihang Mountains. [ Method] Based on daily precipitation data at Shijiazhuang meteorological station in recent 51 years, average rainfall dudng growth periods of the 9 kinds of conventional crops was obtained. Precipitation tendency dudng growth periods of the 9 kinds of conventional crops in plain area before Taihang Mountains was analyzed by Mann-Kendall nonparametric test. [ Result] Seen from rainfall during growth pedods of the different crops, rainfall was the least during the growth period of winter wheat, followed by summer corn. Rainfall during growth peri- ods of the cotton, oil plant, vegetable, fruit tree, potato, rice and legumes was more. Under different guaranteed rates, precipitation change also had difference. Rainfall change during growth periods of the wheat and corn was bigger, and rainfall change during growth period of the rice was smaller. Change degree of the precipitation during growth periods of the cotton, oil plant, vegetable, fruit tree and legumes was equivalent, while precipitation change during growth period of the potato was the biggest. Seen from change tendency of the precipitation during growth periods of the different crops, precipitation in the growth period of winter wheat was increasing at a speed of 0.62 mm/a. However, precipitation in growth periods of the other crops had a decreasing tendency. Precipitation in the growth periods of summer corn and legumes decreased at the same speed which was 2.11 mm/a, while precipitation in growth periods of the cotton, oil plant, vegetable, fruit tree, potato and rice decreased insignificantly. [ Con dusion] The study laid foundation for determination of the agricultural irrigation water and provided theoretical reference for regional agricultural water-saving.

Dynamic Analysis of Land Cover in Four-Lake Area of Jianghan Plain Based on MODIS-EVI Time Series Data

According to the time series data of Enhanced Vegetation Index (EVI) in Four-Lake Area of Jianghan Plain during the period 2001-2007, we use Harmonic Analysis of Time Series (HANTS) to conduct cloud removing processing, and calculate the sum of square N of time series value of each pixel. The pixels with N>0.25 are classified as vegetation coverage area; the pixels with N<0.25 are classified as non-vegetation coverage area. As to vegetation coverage area, we use the second-order difference method to judge the frequency of peak value of EVI time series data. Within one year, the vegetation coverage area with peak value happening 1 time is woodland and grassland; the vegetation coverage area with peak value happening 2 times is arable land; the vegetation coverage area with peak value happening 3 times or more is vegetable land. Supervised classification method is used to identify cities, towns, water area in non-vegetation coverage area and woodland, grassland in vegetation coverage area. We draw the land cover classification diagram of Four-Lake Area in the period 2001-2007. In comparison with the land cover classification based on multitemporal ETM data in 2001, the difference of area of arable land is within 10%. Using MODIS-EVI data, we can rapidly and efficiently conduct land cover classification with low cost. The dynamic analysis results indicate that the area of arable land is in the process of declining, while the area of other cover types shows an increasing trend.

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.

Evaluation of suitability area by ground source heat pump system in Baotou plain

According to the elements of hydrogeological conditions,lithology,stratigraphic thermal physical parameters,construction technology and economic rational elements,the evaluation system of ground source heat pump( GSHP) were established in Baotou plain. The factor weights were determined by using analytic hierarchy process,and the comprehensive element method was selected to evaluate the region suitability of GSHP system. The results show that the suitable area is 559. 63 km2 for utilizing GSHP in the studied area,accounting for 62. 58% of the total area; while the unsuitable area is 334. 60 km2,accounting for37.42%. The evaluating results can provide not only a scientific basis for development and utilization rationally of shallow geothermal heat in Baotou,but also offer an important reference to the other areas.

鄂尔多斯盆地大牛地气田二叠系山西组砂体叠置模式及油气开发意义

河流相砂体储层构型对致密砂岩中相对优质储层的分布规律和天然气开发具有重要意义。通过野外地质剖面和钻井岩心观察,结合测井、录井和岩心分析测试资料,对鄂尔多斯盆地大牛地气田大12井区二叠系山西组致密砂岩的砂体构型要素、叠置模式及油气开发意义进行了研究。研究结果表明:(1)鄂尔多斯盆地大牛地气田大12井区二叠系山西组发育六级复合辫流带和五级单一辫流带,其中单一辫流带包括河床(分流河道)和河漫共2个四级构型单元,河道内单个心滩沉积包含有三级增生体和落淤层;(2)辫状河三角洲平原五级单一辫流带中的四级泛滥平原沉积较辫状河河漫沉积更加发育,辫状河心滩沉积中落淤层欠发育;(3)山西组上部山2-2亚段辫状河单一辫流带内砂体呈“河道-心滩”连续沉积,泥质不发育,砂体叠置程度高(多呈复合式叠置)、连通性好,优质储层多;(4)山西组中下部山1段和山2-1亚段三角洲平原沉积中,西部河道连片性好,砂体以复合式和侧拼式叠置样式为主,连通性和生产效果均较好,东部砂体多为孤立式和侧接式,砂体钻遇率低,单井产量差。

兴城市典型海水入侵区水文地球化学特征

为了揭示兴城滨海平原区海水入侵过程中地下水化学成分演化规律和复杂的水文地球化学作用,在兴城河曹庄镇段至烟台河沙后所镇段内采集了44个地下水样本和1个海水样本,测定其水化学成分及氢氧同位素,通过分析其变化特征探讨兴城典型海水入侵区的水文地球化学特征及其形成作用。结果表明:①区内地下水化学场呈明显的水平分带性,水质由内陆到滨海依次为淡水、微咸水-咸水,地下淡水的水化学类型主要为HCO_(3)-Ca、HCO_(3)·Cl-Ca以及SO_(4)-Ca型等,微咸水及咸水的水化学类型主要为Cl-Na型或Cl-Ca型;②区内地下水主要由大气降水补给,地下淡水主要受控于溶滤作用,而微咸水因受到蒸发作用及混合作用影响,造成氧漂移;③微咸水以Cl^(−)组分为代表的海水与淡水混合比例为0.45%~3.46%,咸水的混合比例约为15.85%,微咸水、咸水的形成为混合作用、蒸发浓缩作用以及阳离子交替吸附作用等共同影响所致。

治涝导向的平原河网地区海绵城市实施路径探索——以宿迁市国家海绵城市示范系统化实施方案为例

针对平原河网地区的排涝特征与问题,在梳理构建治涝片区排水格局的基础上分类提出了针对性的治涝策略。对于具有一定坡度。在多数时期可以实现自排的治涝片区,采用“上蓄+中分+下排”模式,分段缓解排涝压力,提高城区排涝标准对于整体地势低洼,在多数时期很难自排的治涝片区,采用“建闸营圩,蓄排并举”模式,将雨水排口分散建设小型雨水泵站的模式调整为片区排涝主干河道末端建设大型排涝泵站的模式,充分利用片区内部河网的输送和调蓄能力,增强城区应对暴雨的韧性。

氢氧同位素组成对丰沛平原区水循环的指示意义

丰沛平原区包括丰县、沛县与铜山区北部,近年来该地区出现地下水超采、地下水氟污染等严重的问题。为调查该地区水循环情况,采集了地表水与地下水样品共28个,分析了氢氧同位素组成的分布规律及其影响因素,并讨论了丰沛平原区浅层地下水与地表水转化关系以及各自的蒸发损失情况。研究结果表明:大气降水的云下二次蒸发程度较小,地下水的蒸发比附近地区更强烈。地下水同位素含量呈现总体沿地下径流方向逐渐富集的趋势,且地下水^(18)O与CO_(2)存在微弱的交换作用导致^(18)O贫化。结合水文地质调查与氢氧同位素特征,推断出河流中上游更倾向于地下水补给地表水,河流下游地表水对地下水大量渗漏。利用两端元法计算得出,总体上地表水受到地下水补给的比例为20%~40%左右,部分地区补给比例达60%以上。河流下游河水对地下水的补给比例大多介于25%~50%不等,部分点位可达90%。采用非平衡分馏条件下的Rayleigh模型计算蒸发比例,河水的蒸发损失约为23%~28%,地下水蒸发损失约为15%~20%。结果可为丰沛平原区及周边相似地区的水资源管理提供科学参考。

基于AHP-熵权法的鄞西平原河网水环境改善效果综合评价

随着城市化的发展,河流间原有的联系被打断,水动力条件变差,继而引发水质污染、水生态功能衰退等问题。以鄞西平原为例,提出一种基于层次分析-熵权法的水环境改善效果评估方法,在水动力、水质参数的基础上,综合考虑经济效益和感官参数,全面评估水环境改善方案的效果。量化比选研究区提升效果,最终确定方案3为研究区改善效果最优方案。研究表明,基于层次分析法和熵权法的综合评价方法相较于传统仅考虑水动力、水质或其他单一因素的评价方法,能够克服定性数据和主观赋权对评价结果的影响,更加全面地评价不同连通方案的提升效果,实现了方案综合评价与优选。