Changing and Developing Trend of the Farmland Requisition-Compensation Balance Policy in China

The importance and necessity of implementing the balance system of farmland requisition and compensation are reasoned.The changing path of the balance system of farmland requisition-compensation is overviewed.In addition,the problems exist in the implementation of the balance system of farmland requisition-compensation are analyzed as well,covering the increasing demands on land in the process of economic development;the serious phenomenon of wasting land in urban construction;part of farmlands should be revoked from the perspective of ecological construction and environmental protection,which lead to the shortage of reserved farmland and it is hard to implement the balance system of farmland requisition-compensation;the problems of "occupying more but compensating less,occupying good land but compensating bad land" are universal;the development and reclamation of farmlands have taken certain threats to ecological environment;the differences of various regions have not been taken into consideration in implementing the balance system of farmland requisition-compensation.Some notes on the developing trend of farmlands requisition-compensation balance system are put forward.The farmlands should be occupied after being compensated first,so as to ensure the dynamic balance of the total amount of farmlands;the government should encourage the improvement of farmland with mediocre and low output,so as to enhance its production capability;the potential of urban and rural construction land use should be fully developed and the occupation of farmland should be reduced as few as possible;various aspects should be cooperated to increase the possibility of requisition-compensation among different regions.

A Distributed Monthly Water Balance Model for Analyzing Impacts of Land Cover Change on Flow Regimes

The Miyun Reservoir is the most important water source for Beijing Municipality, the capital of China with a population of more than 12 million. In recent decades, the inflow to the reservoir has shown a decreasing trend, which has seriously threatened water use in Beijing. In order to analyze the influents of land use and cover change (LUCC) upon inflow to Miyun Reservoir, terrain and land use information from remote sensing were utilized with a revised evapotranspiration estimation formula; a water loss model under conditions of human impacts was introduced; and a distributed monthly water balance model was established and applied to the Chaobai River Basin controlled by the Miyun Reservoir. The model simulation suggested that not only the impact of land cover change on evapotranspiration, but also the extra water loss caused by human activities, such as the water and soil conservation development projects should be considered. Although these development projects were of great benefit to human and ecological protection, they could reallocate water resources in time and space, and in a sense thereby influence the stream flow.

Evapotranspiration Estimation Based on MODIS Products and Surface Energy Balance Algorithms for Land(SEBAL) Model in Sanjiang Plain,Northeast China

In this study,the Surface Energy Balance Algorithms for Land(SEBAL) model and Moderate Resolution Imaging Spectroradiometer(MODIS) products from Terra satellite were combined with meteorological data to estimate evapotranspiration(ET) over the Sanjiang Plain,Northeast China.Land cover/land use was classified by using a recursive partitioning and regression tree with MODIS Normalized Difference Vegetation Index(NDVI) time series data,which were reconstructed based on the Savitzky-Golay filtering approach.The MODIS product Quality Assessment Science Data Sets(QA-SDS) was analyzed and all scenes with valid data covering more than 75% of the Sanjiang Plain were selected for the SEBAL modeling.This provided 12 overpasses during 184-day growing season from May 1st to October 31st,2006.Daily ET estimated by the SEBAL model was misestimaed at the range of-11.29% to 27.57% compared with that measured by Eddy Covariance system(10.52% on average).The validation results show that seasonal ET from the SEBAL model is comparable to that from ground observation within 8.86% of deviation.Our results reveal that the time series daily ET of different land cover/use increases from vegetation on-going until June or July and then decreases as vegetation senesced.Seasonal ET is lower in dry farmland(average(Ave):491 mm) and paddy field(Ave:522 mm) and increases in wetlands to more than 586 mm.As expected,higher seasonal ET values are observed for the Xingkai Lake in the southeastern part of the Sanjiang Plain(Ave:823 mm),broadleaf forest(Ave:666 mm) and mixed wood(Ave:622 mm) in the southern/western Sanjiang Plain.The ET estimation with SEBAL using MODIS products can provide decision support for operational water management issues.

Balance of Datum Land Prices Among Cities Based on the City Gravitation Model and Stochastic Diffusion Equation

A balance of urban datum land prices is achieved to harmonize regional land prices and make the prices truly reflect different economic development levels and land prices among cities. The current piecewise linear interpolation balance method widely used has two drawbacks that always lead to an unsatisfactory balance among some cities. When the excess of land price in the central city to the surrounding zone reaches a certain degree, land price in the circumjacent city is not only consistent with the local land grade and land use level, but also influenced by the diffusion of land price in the central city. Thus, a new balanced scheme of datum land prices based on the city gravitation model and stochastic diffusion equation is brought forward. Finally, the new method is examined in the practice of datum land price balance in Hubei Province, China.

Analysis of Soil and Water Balance on the Land Arrangement Function

The natural supply of land resources is limited, but the economic supply may change along with social and economic development, and its size is decided bye nature and social and economic body conditions. When the supplying ability of land resources threatens the development of society and the conflict between people and land becomes tense, it forced people to im- prove land utilization and to increase the effective supply of land resources. The paper made an overall consideration on the characteristics of the irrigated farming and the frail ecological environment in Fuhai County, Altay Area, Xinjiang Uigur Autonomous Region and explored land arrangement planning as well as water resource planning and environmental protection. The paper evaluated natural resources, land utilization and water resource of the case study areas and focused on the spatio-temporal balance between the utilization of water and land resources. In the end the paper a feasible plan was made out for the land arrangement project.

EVAPORATION AND WATER BALANCE IN ARID LAND——AN EXAMPIE IN TURPAN,XINJIANG,CHINA

This paper discussed some observation and calculation methods of evaporation and itscharacteristics in arid land taken an example in Turpan, Xinjiang, China by using the dataobtained from July 1, 1991 to June 30, 1992 in the observation station which was settled forthe Japan-China cooperation study in the marginal area of an oasis in Turpan, Xinjiang,China. It is pointed out that due to very low water content in arid land, real evaporation de-

Study on the Balance of Agricultural Water and Land Resources on Ningxia Plain

The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960-2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation,②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level.③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land.

A Study on the Standard Land Price Balance of Urban Commercial Land in Henan Province

The standard land price balance is an important part of urban land price balance. This paper builds different levels of factor layer to carry out a balance study on the urban commercial land in 18 cities of Henan Province,and divides the 18 cities into five categories. Results show that the level of land price is basically consistent with the level of economic development in various cities,and affected by local policies,the land price is too low in some cities.

Balance of Urban Benchmark Land Price in Henan Province:A Case Study of Residential Land

Benchmark land price balance is an important content of urban benchmark land price work.In this paper,by building different levels of factor layers,the balance of urban residential land in 18 cities of Henan Province is studied,and the 18 cities can be divided into five categories.It is found that the urban land price level is basically consistent with the level of economic development,and some urban land price is lower due to local policy.

Research on the Balance of Urban Benchmark Land Price in Henan Province : A Case Study of Commercial Land

The balance of benchmark land price is an important part of the work of urban benchmark land price.By constructing different levels of factor layers,the balance of benchmark land price of urban commercial land in the urban areas of 18 provincial cities in Henan Province was studied.The urban areas were divided into 5 classes.It is found that the land price level in each urban area is basically consistent with the level of economic development,and the land price in some urban areas is low under the influnece of local policy.

Study on Ecological Land Demand of Shijiazhuang City Based on Carbon-Oxygen Balance Method

[Objective] The study aimed to analyze ecological land demand of Shijiazhuang City on the basis of carbon-oxygen balance method. [Method] Firstly, the release and absorption of CO2 and O2 in Shijiazhuang City during 2004 -2007 were studied by using carbon-oxygen balance method, and the ecological land area needed for carbon-oxygen balance was calculated, then the ecological land area needed for carbon-oxygen balance in 2015 was predicted. Finally, some measures to reduce the deficit of CO2 and O2 in Shijiazhuang were proposed. [Result] From 2004 to 2007, the unbalance between CO2 and O2 aggravated with the rapid development of Shijiazhuang City＇s economy, and the ecological land needed increased year by year. If the amount of CO2 released and 02 consumed grows constantly, the area of standard ecological land needed will be about doubled in 2015 compared with 2007 （ 1. 575 6 million hm2 ）, namely increasing to 3.566 million hm2. In addition, appropdately improving the area of mixed forest and other vegetation with higher net production, developing some green energy resources like nuclear energy and wind energy and controlling its population could be adopted to reduce the deficit of CO2 and 02 in Shijiazhuang City. ~ ConclusionJ The research could provide theoretical references for the overall plan of land utilization in Shijiazhuang City. Key words Shijiazhuang; Ecological land; Carbon-oxygen balance; Shijiazhuang City; China

Impacts of forestation on the annual and seasonal water balance of a tropical catchment under climate change

Background:This study aims to assess the effects of a forestation program and climate change on the annual and seasonal water balance of the Bogowonto catchment(597 km^(2))in Java,Indonesia.The catchment study is rare example in Indonesia where forestation has been applied at the catchment level.However,since the forestation program has been initiated,evaluations of the program only focus on the planting area targets,while the environmental success e.g.,impacts on the hydrological processes have never been assessed.This study used a calibrated Soil and Water Assessment Tool(SWAT)model to diagnose the isolated and combined effects of forestation and climate change on five water balance components,namely streamflow(Q),evapotranspiration(ET),surface runoff(Q_(s)),lateral flow(Q_(l))and base flow(Q_(b)).Results:The results show that from 2006 to 2019,forest cover has increased from 2.7% to 12.8% of the total area,while in the same period there was an increase in the mean annual and seasonal temperature,rainfall,and streamflow.Results of SWAT simulations show that changes in the mean annual and seasonal water balance under the forestation only scenario were relatively minor,while changes were more pronounced under the climate change only scenario.Based on the combined impacts scenario,it was observed that the effects of a larger forest area on the water balance were smaller than the effects of climate change.Conclusions:Although we found that forestation program has minor impacts compared to that of climate change on the hydrological processes in the Bogowonto catchment,seasonally,forestation activity has decreased the streamflow and surface runoff during the wet season which may reduce the risk of moderate floods.However,much attention should be paid to the way how forestation may result in severe drought events during the dry season.Finally,we urge the importance of accounting for the positive and negative effects in future forestation programs.

Effect on greenhouse gas balance of converting rice paddies to vegetable production

Rice paddies are increasingly being converted to vegetable production due to economic benefits related,in part,to changes in demand during recent decades.Here,we implemented a parallel field experiment to simultaneously measure annual emissions of CH_4and N_2O,and soil organic carbon(SOC)stock changes,in rice paddies(RP),rice paddy–converted conventional vegetable fields(CV),and rice paddy–converted greenhouse vegetable fields(GV).Changing from rice to vegetable production reduced CH_4emissions by nearly 100%,and also triggered substantial N_2O emissions.Furthermore,annual N_2O emissions from GV significantly exceeded those from CV due to lower soil p H and higher soil temperature.Marginal SOC losses occurred after one year of cultivation of RP,CV,and GV,contributing an important share(3.4%,32.2%,and 10.3%,respectively)of the overall global warming potential(GWP)balance.The decline in CH_4emissions outweighed the increased N_2O emissions and SOC losses in CV and GV,leading to a 13%–30%reduction in annual GWP as compared to RP.These results suggest that large-scale expansion of vegetable production at the expense of rice paddies is beneficial for mitigating climate change in terms of the overall GWP.

城乡建设用地增减挂钩政策与城乡收入差距

在空间均衡视角下,建立理论模型分析城乡建设用地增减挂钩政策对城乡收入差距的影响,并通过实证分析进行政策评估的结果表明:增减挂钩政策能够提高城乡居民人均收入,但是对城市居民人均收入提高幅度更多,从而加大城乡收入差距。如果配套实施农村生产率提升的增减挂钩政策,在提高城乡居民人均收入的同时,这种综合性改革能够促使农村人均收入提高幅度更大,进而缩小城乡收入差距。随后,基于2000—2016年省级面板数据,采用逐期双重差分法与合成控制法分别评估城乡建设用地增减挂钩政策与配套实施农村生产率提升的增减挂钩政策对城乡收入差距影响的实证结果发现:自2006年实施增减挂钩政策后,增减挂钩试点省份的城乡收入差距均值提升0.125,达到2.820;自2008年实施配套农村生产率提升的增减挂钩政策后,重庆市的城乡收入差距均值下降0.261,达到3.043。基于此,在城乡融合背景下,我们应建立健全城乡统一建设用地市场制度。

旱区陆面非降水性水分研究进展和展望

随着全球气候变暖,自然生态系统和水资源压力不断增加,加剧了全球水资源的短缺。旱区非降水性水分(Non-precipitation Water,NPW),作为一种重要的水源,对旱区生态系统和陆面水分平衡具有显著影响。本文基于国内外非降水性水分研究现状,总结其在西北旱区的观测方法、变化特征、形成机制及对陆面水分平衡和作物的影响。在结合非降水性水分研究国际趋势的基础上,指出当前研究的不足和问题,以及未来研究的重点方向:揭示陆面非降水性水分的复杂形成机制,加强对不同气候区和下垫面非降水性水分的认知,建立专门的陆面非降水性水分观测系统,发展其在数值模式中的参数化,以及制定陆面非降水性水分开发利用的技术标准。

价值均衡视角下宅基地使用权继承纠纷的裁判规则构建

现阶段宅基地使用权继承纠纷解决存在司法处理态度不一、缺少统一立法规范的实践困境。根本原因在于宅基地使用权兼具身份价值和财产价值,而现有纠纷处理模式不能达成两种价值取向的均衡。鉴于此,建议适用“身份资格—房地关系”双重标准的限制继承规则作为司法裁判指引,同时明确“三权分置”背景下宅基地使用权的成员权内涵,以填补双重标准裁判规则的理论漏洞,消解新规则的内在矛盾。

黑龙江省奶牛粪污土地承载力时空分布特征分析

为了探究黑龙江省奶牛粪污对土壤造成的潜在污染风险,本研究选取2015—2022年黑龙江省奶牛养殖和农作物产量等数据,量化分析奶牛粪污养分供给量和农作物粪污养分需求量,测算黑龙江省各市(地区)奶牛粪污土地承载力及其指数。结果表明:黑龙江省奶牛粪污氮、磷养分供给量和奶牛粪污土地承载力大体呈下降趋势,农作物粪污氮、磷养分需求量大体呈上升趋势;全省奶牛粪污污染风险主要集中在大庆市,齐齐哈尔市奶牛粪污土地承载力一直处于较高水平,鸡西市、鹤岗市、双鸭山市、佳木斯市、黑河市和大兴安岭地区奶牛粪污氮、磷供给量远低于农作物粪污氮、磷养分需求量。整体上,黑龙江省内土地消纳奶牛粪污量未超过环境容量,奶牛养殖仍具有一定的发展潜力。因此,建议从调整优化奶牛养殖区域布局、搭建有机肥供需平台、提升有机肥使用积极性和技术指导三个层面推动黑龙江省奶牛养殖业高质量发展。

南昌市土地利用碳收支时空分异及碳平衡分区

本文基于土地利用碳源碳汇核算方法,计算了南昌市2000—2020年碳收支量,利用基尼系数、熵权-TOPSIS、耦合协调度距离模型等方法分析其空间碳平衡贴近度,构建碳平衡分区评价体系,并引用三维魔方单元模型探讨南昌市碳平衡分区。结果表明:(1)2000—2020年,南昌市碳收支量整体呈现上升状态。碳排放高值区环主城呈反“C”型分布,碳汇呈现出以西湖区、东湖区为低值中心,向外逐步增加的外围—核心结构。(2)在分异格局上,碳源、碳汇均呈现西北—东南主导方向,空间分布重心稳定,且存在普遍的碳排放关联关系。(3)2000—2020年南昌市各县区的碳源碳汇处于高度不协调状态,两者耦合协调性较差,存在失衡状况。(4)基于碳平衡分析,将南昌市9个县区分为碳强度控制区、低碳优化区、碳收支平衡区,旨在因地制宜为南昌市各县区制定协同减排的土地利用政策,以及制定更加精准和可行的减碳增效方案提供科学的支撑。

新疆北部城市碳排放时空分异与碳平衡分区

研究城市土地利用碳排放时空格局与碳平衡分区,对实现碳减排和“双碳”目标至关重要。以新疆北部46个县市为研究区,利用土地利用与能源数据,通过碳排放系数法计算2000—2020年土地利用碳排放,分析碳排放量时空演变情况,对各县市进行碳平衡分区。结果表明:(1)碳排放量呈总体上升趋势,2016—2020年呈现指数型上升的趋势,碳吸收量缓慢下降,碳排放强度先下降后上升,碳排放量远大于碳吸收量。(2)碳排放主要来源于建设用地,天山北坡城市为主要碳排放城市,碳吸收主要来源于草地与林地,伊犁河谷地区、阿尔泰山南部等地城市为主要碳吸收城市。(3)碳排放空间相关性逐渐减弱,热点区集中分布在克拉玛依市附近,冷点区集中分布在伊犁州与阿勒泰地区。(4)依据经济承载力系数、生态承载力系数以及碳排放量划分为碳汇功能区、碳汇优化区、低碳经济区、碳源优化区和高碳控制区五个碳平衡分区。

视觉反馈对慢性踝关节不稳者落地过程中生物力学的影响

背景:落地试验可以有效观察慢性踝关节不稳患者的下肢运动生物力学指标,分析影响慢性踝关节不稳姿势稳定性的平衡调节策略,以期为慢性踝关节不稳患者避免再次损伤以及损伤后临床康复提供有价值的参考依据。目的:通过观察落地过程中睁眼和闭眼时慢性踝关节不稳患者的运动学和动力学指标,分析视觉对慢性踝关节不稳姿势稳定性的影响及平衡调节策略的变化。方法:31例慢性踝关节不稳患者健、患侧腿分别在睁眼和闭眼条件下,从40 cm跳台单腿落地,采用三维运动捕捉系统采集落地过程中的动力学和运动学数据,配对t检验比较健、患侧腿在两种条件下落地的差异性。结果与结论:(1)动力学指标:闭眼时患侧踝关节前方、后方以及垂直方向地面反作用力峰值相对值大于睁眼条件下,且垂直方向地面反作用力峰值出现时间晚于睁眼时(P<0.05);(2)运动学指标:在闭眼条件下,健、患侧腿膝触地时屈曲角度均大于睁眼条件下(P<0.05),患侧膝、踝最大屈曲角度及前馈角度变化大于患侧睁眼条件下(P<0.05),落地稳定时间较睁眼时延长(P<0.05);(3)提示在去除视觉输入的条件下,慢性踝关节不稳者在落地过程中地面反作用力峰值增大、落地关节角度增大、维持姿势稳定所需的时间延长,加大了落地损伤的概率,视觉对慢性踝关节不稳患者平衡的维持起到前庭觉和本体感觉不能弥补的作用。