Importance and Countermeasures of Curbing the Conversion of Agricultural Land to Non-agricultural Land under the Background of the Rural Revitalization Strategy

Farmland is the most basic element for farmers’survival and development,and has a social security function.The conversion of agricultural land to non-agricultural land has gradually become the primary factor in the reduction of agricultural land in various regions of China,seriously endangering China’s food security.Under the background of the rural revitalization strategy,the emergence of the conversion of agricultural land to non-agricultural land and the inevitability of its development were analyzed from both the acceleration of urbanization and the increase in land demand by using the literature research method.The importance of curbing the conversion of agricultural land to non-agricultural land to achieve the grand goal of strong agriculture,beautiful rural areas,and rich farmers was clarified,and then countermeasures and suggestions to curb the conversion of agricultural land to non-agricultural land were put forward,which is of great significance to promoting the effective implementation of China’s rural revitalization strategy.

Carbon Sink Effects in Conversion of Farmland to Forest Project in Karst Drainage Basin——A Case of Hongfenghu Drainage Basin in Guizhou Province

[Objective]Study on carbon sink effects in Conversion of Farmland to Forest Project in Hongfenghu drainage basin in order to provide evidences for assessing carbon sink potential of conversion of farmland to forest in Guizhou Province.[Method]By investigating the implement of Conversion of Farmland to Forest Project in Hongfenghu drainage basin from 2000 to 2006,the carbon sink amount and effect of seven main tree species in the foreat region like Cunninghamia lanceolata,Cryptomeria fortunei,Amygdalus persica,Prunus salicina,Armeniaca vulgaris,Camptotheca acuminate and Catalpa bungei were calculated,based on which the amount of forest carbon sinks in Hongfenghu drainage basin in 2015 was estimated.[Result]Biomass storage and carbon sink amount in middle and young aged forests were increasing over time from 2000 to 2006,which reached 1.05×107 kg by 2006 and would engage more and more potential.Cunninghamia lanceolata has the superior carbon sink capacity in the seven tree species in the research region,of which the amount of carbon sink per unit area will be 106.51 t/hm2 by 2015,followed by Cryptomeria fortunei with the amount of carbon sink per unit area by 99.42 t/hm2.Armeniaca vulgaris has the weakest carbon sink capacity of all the seven species with the amount of 13.03 t/hm2.The total amount of carbon sink in seven tree species was 2.35×107 kg,while the average amount of carbon sink per unit area was 26.17 t/hm2,which could produced economic benefit of 7.17×106 yuan calculated on the price of 305.0 yuan/t or 5.91×106 yuan calculated on the price of 254.1 yuan/t.[Conclusion]Economic benefits of carbon sink effects of Conversion of Farmland to Forest Project in Hongfenghu drainage basin were great with huge appreciation potential.

Farmers′ Perception to Farmland Conversion: A Questionnaire Survey in Xining City, Qinghai Province, China

China is experiencing a fast process of farmland conversion which is conducted mainly by local governments to fuel economic development.Social tension is aroused and policy makers take great concerns on coordinating interests among different stakeholders,especially for increasing farmers′ interest.The purpose of this study is to get some insights related to land acquisition institution by exploring farmers′ perception to farmland conversion.Participatory Rural Appraisal(PRA) was applied for the investigation in peri-urban area,of Xining City,Qinghai Province,China.The total of 519 householders from 15 villages completed valid questionnaire survey from July to November,2012.The results indicate that farmland conversion has several impacts on farmers′ life.Most farmers are gradually adapting to city life.Higher living expenses and more income are perceived by farmers with average score of 4.21 and 2.69,respectively.The average scores of 2.38 and 2.46 are for improvement of life security and more job opportunities.Farmers expect to get some stable ways of compensation in addition to lump-sum compensation in cash.Stable subsidies every year and obtaining same number of land received strong proposal.And these two options are cited by 49.6% and 43.9% of respondents.Farmland conversion brings about cleaner living condition and more amenities,but lower air visibility and drier air.Results reflect landless farmers′ economic and life pressures and various demands.Local government should pay more attention to increase farmers′ income and improve rural security system.

Relationship between Farmland Use Right Circulation and Non-agricultural Employment——Based on Survey Data from Eastern and Western China

Relationship between Chinese rural non-agricultural employment and farmland use circulation has always been a hot research topic without final conclusions.This paper uses survey data of"China Health and Retirement Longitudinal Study(CHARLS)"covering 1,549 households of 95 villages in Zhejiang and Gansu Province in 2008.According to the data analysis,Zhejiang Province has a higher ratio of rural households leasing out their farmland than Gansu Province has,while the latter has a higher ratio of rural residents going out for earning a living.In both provinces,non-agricultural employment and farmland use circulation show significant positive correlation,but in Gansu,non-agricultural employment of farmers shows no significant positive correlation with rural households leasing out their farmland.The factor shows that for peasants in underdeveloped regions of west China,they rely more on land because of its social security functions,so they are not willing to lease out their land even when they go to cities for earning a living.For local government,it is not appropriate to promote farmland use circulation by depending on the transfer of rural labor forces,fundamental needs of peasants must be taken into consideration.

Research of Mechanism on the Impact of Local Governmental Competition on Farmland Conversion

In the perspective of local governmental competition, the impact of local governmental competition on farmland conversion is analyzed in terms of political competition, factors competition and products competition, and the empirical analysis is conducted according to the provincial data from 2002 to 2007. The results show that the endowment of land resources correlates negatively with the scale of farmland conversion, and the population, the tendency of exceeding capital investment and the competition of research and development input correlate positively with the scale of farmland conversion. According to these research results, corresponding policies and countermeasures are put forward: we should overhaul the system of performance evaluation of local governmental officials; we should normalize the local governmental competitive behavior.

2000—2020年中国耕地旱改水空间格局演变及其适应性管理

灌溉农业对粮食高产稳定至关重要。近20年中国大力推行旱改水型农田整治,但旱改水的空间格局不清、旱改水转换适宜性不明,限制了旱改水适应性管理及耕地科学保护和永续利用。为此,利用2000—2020年5期30 m×30 m遥感数据,揭示中国耕地旱改水空间格局及其转换特征,并构建地形、气候、土壤与耕作4个维度的适宜性评价体系,评估旱改水工程实施的空间匹配效果,探索适应性管理分区与策略。结果表明:1)2000—2020年全国旱改水耕地面积达1297.04万hm^(2),占耕地总面积的7.31%,主要分布于黑龙江东部、河南中部、四川东部和江苏中部;2)2000—2020年全国旱改水耕地中17.70%为勉强匹配,11.54%为不匹配,旱改水工程实施的总体效果不佳;3)未来应划分不同的旱改水适应性管理分区,按适宜性优先级制定针对规划、利用和服务的差异化旱改水整治策略,研究可为耕地保护、国土空间生态保护和修复规划及两区划定等提供科学依据。

“粮改饲”补贴政策对农地租金的影响及作用机制

“粮改饲”补贴政策主要是通过补贴农业企业撬动农户生产方式改变,以达到农业调控的整体目标,目前鲜有文献研究此类补贴模式对农地租金的影响。该研究首先理论分析了“粮改饲”补贴政策从养殖企业传导到农户进而影响农地租金的传输机制,然后利用2020年和2022年中国乡村振兴综合调查10省份50县300村4384户5894个地块数据,采用双向固定效应模型,实证分析了“粮改饲”补贴政策对农地租金的影响及作用机制。研究结果表明:①“粮改饲”补贴政策显著提高了农户收取土地租金的比例和价格。②机制分析发现,“粮改饲”补贴政策主要通过提高饲料粮种植比例、增加农民收入、培育农地流转市场的方式提高农地流转租金。③异质性分析发现,对于养殖企业附近、耕地资源禀赋较好、土地密集型作物种植区的农地,“粮改饲”补贴对农地租金发挥更大的政策效应;对于劳动力资源禀赋差异,该补贴对农地租金的影响没有表现出显著差异。基于以上研究结论提出政策建议:①优化“粮改饲”补贴政策,将“粮改饲”补贴政策与适宜当地青贮玉米等饲料粮生产的自然条件相结合,减少耕地资源与农产品市场错配,有效发挥耕地资源的使用效率。②优化农地流转市场,发挥土地规模效应,引导农户大规模种植青贮玉米。③探索更加灵活的“粮改饲”补贴模式,鼓励农业企业与农业大户直接合作,通过企业引导农户生产出更加符合市场需求的产品,提高整体的社会福利。

内蒙古退耕还林工程区林冠覆盖率卫星遥感监测

内蒙古新一轮退耕还林还草工程于2015年启动,是内蒙古生态环境建设恢复的重大举措。本文利用2022年生长季Sentinel-2A影像及地形数据,结合实地测量数据,基于GEE平台采用梯度提升树回归模型(GBRT),对内蒙古新一轮退耕还林工程区林冠覆盖率进行反演分析。结果表明,模型验证决定系数(R^(2))为0.87,均方根误差(RMSE)为0.079,平均绝对误差(MAE)为0.062。内蒙古新一轮退耕还林工程区林冠覆盖率均值为0.147,其分布存在明显的空间差异,受植被配置类型、种植年份和地理环境等因素影响,总体从西向东逐渐递增。利用Sentinel-2A影像和地形数据可以有效地估测退耕还林工程区林冠覆盖率,对低林冠覆盖率区域的反演提供参考。

基于参数最优地理探测器的粤东北耕地非农化特征与影响因素研究

[目的]探究粤东北丘陵山区耕地非农化格局及影响机制,为该地区防治耕地非农化提供理论指导。[方法]以粤东北为例,基于该地区1990,2000,2010和2020年4期土地利用影像提取非农化信息,运用空间自相关分析和参数最优地理探测器等方法探究耕地非农化时空分布特征与影响因素。[结果]①1990-2020年,粤东北耕地非农化呈“平稳发展到骤降”的变化趋势,累计非农化面积2.29×105 hm^(2),非农化率25.31%,林地和建设用地是主要的非农化类型。②垂直方向上,海拔1000 m以上和坡度25°~35°的耕地更容易非农化;水平方向上,与建设用地距离50 m以内和与河流距离1000~1500 m的耕地更容易非农化。③粤东北耕地非农化存在显著的正向集聚,全局莫兰指数由0.371逐渐下降至0.255,“高-高”聚类和“低-低”聚类的变化主导着耕地非农化率空间自相关格局的演变。④农业人口和耕地破碎度始终对耕地非农化空间分布具有较强的解释力,近10 a来社会经济因素对非农化的解释力有所减弱。多因素特别是农业因素和社会经济因素的交互能够进一步增加对耕地非农化的解释力。[结论]近30 a来,粤东北耕地非农化面积和空间集聚呈下降趋势,但农业人口和耕地破碎化对非农化的影响进一步增强。应合理控制城镇扩张速度,整合破碎耕地、引入小型农机改善生产条件,同时通过普及农村电子商务等方式鼓励农民种植,以应对耕地非农化问题。

The Development Process,Current Situation and Prospects of the Conversion of Farmland to Forests and Grasses Project in China

The Conversion of Farmland to Forests and Grasses Project is the most symbolic and globally important ecological engineering effort to build the human and natural life community.After the call and mobilization stage since the founding of the People’s Republic of China,the first round of Conversion of Farmland to Forests and Grasses occurred at the end of the 20 th century.With the second round of Conversion of Farmland to Forests And Grasses launched in 2014,the central government has invested 535.3 billion yuan altogether by 2020,and 34.83 million ha have been returned to forest and grassland in 25 provinces(autonomous regions and municipalities)(2435 counties included).Among them,14.23 million ha were returned from farmland;barren hills and wasteland afforestation accounted for 17.53 million ha;and sealed mountain forest cultivation represented 3.07 million ha,accounting for 40%of the total afforestation area of national key projects in the same period,and 41 million households and 158 million farmers benefited directly.The project construction has made great achievements.The total value of ecological benefits has reached 1.42 trillion yuan,plus economic benefits of 0.26 trillion yuan,and social benefits of 0.73 trillion yuan,for a total amount of 2.41 trillion yuan.This effort has made outstanding contributions toward building an ecological civilization and a beautiful China.Looking forward to the future,the Conversion of Farmland to Forests and Grasses will embark on a new stage of high-quality development,which will strive to achieve high-quality construction,high efficiency and a high level of management.China will promote the third round of conversion of farmland to forest and grassland from 2021 to 2035,and it is expected to return 6.67 million ha to forests and grasses.

土地资源管理中县级国土空间总体规划编制问题及对策

针对南华县国土空间总体规划中耕地“非农化”“非粮化”、用地布局缺乏科学性等问题,通过采取工程措施与调出补划相结合的方式,调整规划分区规则以及分类型、分区域布局新增建设用地等措施,使永久基本农田中的“非耕地”面积减少了149.02 hm^(2),农田保护区面积增加了9 607.35 hm^(2),城镇开发边界和村庄建设边界外的新增建设用地规模由6 044.02 hm^(2)下降到417.83 hm^(2)。

Review of Conversion of Farmland to Forests Project:Ranking First in Investment in the World

The Conversion of Farmland to Forests Project (CFF) is one of the six great forest ecological Projects inChina and one of the ten great forest ecological Projects in the world, ranking the third in overall scale and the first ininvestment. CFF was officially initiated in 2002, covering 1897 counties (county-level cities and districts) in 25provinces (autonomous regions or municipalities) of China. The whole investment is more than 40 billion US$ duringabout 20 years (from 1999 to 2017), aiming to form better ecology system in fragile ecology regions and effectivelycontrol the soil and water erosion of the Yangtze and the Yellow River and sandstorm of the Three-north Regions inChina. The experimental Project of CFF began in 1999, including Sichuan, Shanxi and Gansu province, and the scopeof CFF was widened later. About 1.16 million ha of farmlands were converted to forestlands, and one million ha ofplantation in mountains and wasted lands were completed in 3 years, involving 20 provinces (autonomous regions andmunicipalities), 400 counties, 27 thousand villages, 5.7 thousand towns, 4.1 million farm families and 16 millionfarmers.

Farmland to Forest Conversion Suspended

Due to a lack of farmland,a reforestation project in its eighth year has been tem- porarily suspended

农田氮磷生态拦截沟工程对粮食功能区氮磷减排效果

农业生产中的氮、磷等养分流失是农田生态系统、水体与湿地生态系统中养分盈余的主要来源,是造成面源污染的重要原因。生态沟渠对传统农田排水沟渠系统进行升级与改造,通过土壤-微生物-植物形成生态链平衡系统,利用其新陈代谢协同降解农田排水中的有机物、氮、磷等污染物,同时辅助脱氮除磷装置、拦截转化池和底泥污染捕获系统等功能性设备,进一步提高农田排水中污染物的拦截效果。在该沟渠建设实例中,通过对农田氮磷生态沟渠水质中的总氮、总磷、氨氮和高锰酸盐指数进行监测分析并得出有效去除率,观测到农田氮磷生态沟渠能够显著降低农田排水中氨氮、总氮和总磷的浓度,并且沟渠中的拦截设施对污染物的去除效果明显,为萧山区粮食功能区农业面源减排提供技术模板,为进一步推动绿色农业发展创造了有利条件。

中国耕地非农化对经济增长贡献的地区差异分析

现阶段中国耕地非农化对经济增长贡献存在地区差异,掌握差异的主要来源和变化趋势有利于耕地非农化指标的高效调配,促进地区经济增长的协调发展。利用1989～2001年我国东、中、西部建设用地占用耕地面积和国内生产总值的分省数据,测算了以建设用地占用耕地面积和GDP增量为对象的基尼系数、加权变异系数以及泰尔指数等指标,并对泰尔指数进行因素分解得到差异的主要来源和变化趋势。结果表明:三类地区内部省际差异是总体差异的主要来源,其中东部内部差异对总体差异贡献增大、中部减小、西部有先增大后减小趋势。鉴于此,从促进资源的高效利用和保护地区间公平发展环境的角度出发,耕地非农化指标调控的重点在于三类地区各自内部省份之间的调剂。

岷江上游生态补偿的博弈论

为了建立合理的生态补偿机制,制定更为科学的生态补偿政策,以岷江上游退耕还林补偿为例,运用博弈论模型考察了岷江上游现有生态补偿机制,以及在补偿政策实践过程中补偿主体与补偿对象之间的决策和行为过程。结果表明:(1)长期来看,生态补偿政策的实施效果不完全在于补偿金额的大小,仅仅依靠提高对生态建设者(保护者)的补偿标准来保护环境是不明智的;(2)生态补偿年限对岷江上游地区生态补偿政策的实施效果起着重要作用,政府制定生态补偿政策时应该将补偿年限纳入政策制定范畴中,并作为重点考虑的因素;(3)岷江上游地区第三产业的发展水平及生态建设者(保护者)外出务工收入水平的高低直接影响生态建设工程实施的效果;(4)对生态补偿的重要策略是应该通过建立相应的配套措施来增加农民务工的机会。

基于MODIS/NDVI的陕北地区植被动态监测与评价

陕北地区从1999年退耕还林试点工程实施以来,区域植被发生很大变化,退耕前后植被动态变化监测成为退耕还林工程评价任务之一,而当前植被恢复监测评价的难点在于如何确定哪些是由于退耕而引起的植被变化。针对此问题,选取适合陕北地区植被变化监测的MOD IS/NDVI数据,利用均值变化及趋势分析方法,从不同土地利用/覆被类型和不同坡度植被指数动态变化两方面分析退耕还林对植被动态变化的影响。结论如下:(1)陕北地区平均NDVI从2000—2008年呈现较明显的增长趋势,坡耕地和草地NDVI增长速度相对较快;(2)趋势分析结果显示,陕北绝大部分地区植被恢复良好,植被指数呈明显改善的面积占整个地区面积的64.96%,中度改善占18.58%,其中又以坡耕地、草地植被明显改善面积分别占陕北地区明显改善面积的45.43%和17.10%,坡耕地对陕北地区植被明显改善面积贡献最大;(3)7-15°、15-25°及25-35°坡度植被明显改善面积分别占总改善面积的39.91%、25.81%、2.28%,其中7-25°坡度植被明显改善面积占总面积的65.72%;(4)基于陕北地区近年气候呈暖干化发展趋势,同期降雨并未呈现显著变化,说明非气候因子中退耕还林等人为因素是引起NDVI增长的主要因素,退耕还林对于陕北地区植被恢复有明显促进作用。

不同退耕模式下土壤水稳性团聚体及其有机碳分布特征

采用野外调查和室内分析相结合的方法,对退耕还茶地和退耕还林地土壤水稳性团聚体及其有机碳分布特征进行研究。结果表明:(1)不同土层退耕还茶地土壤各粒径水稳性团聚体占总团聚体的比例均以<0.25mm的含量最大,且与其他粒径间存在极显著差异;除2～1mm粒径外,退耕还茶地土壤与退耕还林地同粒级水稳性团聚体含量差异不显著。(2)0-20cm土层,团聚体的平均重量直径和平均几何直径表现为退耕还林较退耕还茶大,虽退耕还茶地破坏率与退耕还林的差异不显著,但退耕还茶地土壤团聚体破坏率高于退耕还林地的;20-40cm土层结果与之相反。(3)0-20cm土层,退耕还茶地随着水稳性团聚体粒径的减小土壤有机碳含量呈先减少,再增加,然后减少,最后增加的变化,且退耕还茶地土壤有机碳含量较退耕还林的高;20-40cm土层,退耕还茶地随着水稳性团聚体粒径的减小土壤有机碳含量呈先减少,再增加,最后减少的变化,除0.5～0.25mm和>5mm这2个粒级外,退耕还茶地土壤有机碳含量较退耕还林的低。

农户农地城市流转意愿及其影响因素分析——以武汉市城乡交错区农户为例

研究农户农地城市流转意愿对实现合理的农地城市流转、促进城乡协调发展具有现实意义。依据武汉市远城区和近城区33村143户农户实地随机抽样样本,采用Logistic模型对影响农户农地城市流转意愿的因子进行定量分析,结果表明基础设施与服务的改善、社会保障制度的建立是影响远、近城区农户农地意愿的主要影响因素,近城区农户的意愿还受农地补偿收益的影响。针对影响力最大的因子采取措施,可以最大程度符合农户意愿,保障农户利益,在满足建设用地需求与农户保有农地之间寻找均衡。

粮食安全:西北地区退耕对粮食生产的可能影响

据西北五省区制定的规划或计划,到2010年将累计退耕400×104hm2,约占现有耕地面积的1/4。按照目前的单产水平和粮食作物比例,西北地区将减少粮食产量近400×104t,相当于1996年西北地区粮食总产量的1/8。同时,退耕对当地的粮食生产存在正面影响,主要表现在:①退耕节省下来的生产要素的转移可以带来未退耕耕地粮食产量提高;②西北地区生态环境以及局地小生境的改善可以促进粮食生产、降低灾害风险。此外,农业科技进步和工程设施建设的加强,会对保留耕地上的粮食生产起到极大的推动作用。通过对西北五省区粮食单产的预测并结合人口预测可知,2010年西北地区粮食总产量可达4516.9×104t,在人均400kg、425kg和450kg水平下粮食需求分别为3936.1×104t、4182.1×104t和4428.1×104t。因此,从长远的角度来看,就西北地区整体而言将不会出现粮食短缺,但粮食盈余水平较低;而就具体省区而言,陕西、甘肃和青海三省区必须通过粮食调入才能满足本省区需求,而新疆和宁夏粮食则有一定盈余。