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.

Evaluation of the Land Production Potential in the Context of Returning Farmland to Forest in Karst Region:A Case Study of Guizhou Province

In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test on the actual production capacity of land and the forecasted production capacity of land in 2007 and 2008, and then conduct comprehensive forecast of the land production potential in Guizhou Province in 2020. On this basis, considering the nutritional standards needed by three kinds of life type (dressing warmly and eating one's fill, well-off life, relatively affluent life), we evaluate the land production potential in Guizhou Province under the project of returning farmland to forest. Based on the evaluation results, we put forth the relevant recommendations for achieving sustainable land use in the context of returning farmland to forest in Guizhou Province.

THE STRUCTURE AND DYNAMICS OF THE LAND RESOURCES SYSTEM IN THE FARMLAND SHELTER FOREST REGION IN THE NORTHEAST PLAIN

The structure and dynamics of land resources system in the shelter forest region in the Northeast Plain is discussed according to the remote sensing and statistical information from the typical profiles and spots. For agricultural utilization, the land resources system is made up of five components, i.e. man, land resources, water resources,climatic resources and barren land. The local economy depends heavily upon its land resources, especially farm land. Having been exploited for 50-60 years from the 1930s to 1980s, it has already changed from the reclaiming period into the declining period.There is no waste land to be reclaimed. Facing the increase of population and requirements and the decrease of farmland fertility, proper management of land resources is indispensable if local economic and living level is maintained. It is imperative to make artificial regeneration (highest input) for the land resources and to keep fine circle of thesystem. If only natural regeneration if relied, the system will be changed to vicious circle.

Conversion of Andean montane forest to exotic forest plantation modifies soil physicochemical properties in the buffer zone of Ecuador's Podocarpus National Park

Background:Andean montane forests(AMF)are biodiversity hotspots that provide fundamental hydrological services as well as carbon storage and sequestration.In recent decades,southern Ecuador AMFs have been seriously threatened by increased logging and conversion to forest plantations with exotic species.In this context,our main objective was to evaluate the effects of AMF conversion to forest plantations on soil physicochemical properties in the buffer zone(Bz)of the Podocarpus National Park(PNP),in southern Ecuador.For this purpose,random samples were taken at a depth of 0-10 cm in four plots in each contrast zone and analyzed for bulk density,porosity,textural class,leaf litter depth,soil pH,as well as the contents of organic matter(SOM),soil organic carbon(SOC),total nitrogen,and available phosphorus and potassium.Results:The results indicate that the conversion of AMFs produces an increase in bulk density and a decrease in SOM,SOC,and total nitrogen contents,thus modifying soil properties,which could result in a decrease in water regulation capacity and produce an increased risk of soil erosion.This accelerates degradation processes,as well as threatens shortages of the drinking water supply.Conclusions:This study can help decision-makers to implement soil management plans in the Bz of the PNP,based on the implementation of new regulations,where the conservation of AMF is promoted.In addition,it is recommended to apply environmental restoration strategies in the anthropized areas of the AMF,as well as in the areas with exotic eucalyptus and pine plantations.

Application of the Modified Neighborhood Interference Model to the Cultivation of Forest and Herbaceous Ecosystem

This paper is an extension of the application of neighborhood interference model--being modified--to the study of the interference between forest plants and herbaceous plants. The exploration of the neighborhood interference between triploid Populus tomentosa and Lolium multiflorum shows that the interference of Lolium multiflorum on triploid populus tomentosa is positive, with the primary interference factor living weight, and secondary factor cover degree; the growth of an individual tree is affected by the number, height, and coverage of the Lolium multiflorum; the more dense the coverage of the Lolium multiflorum in a certain area, the taller, faster and more trees will grow as a result of a greater positive neighborhood interference. The modified neighborhood interference model well serves as an effective approach to extend the application of neighborhood interference researches.

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.

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.

退耕还林地生态环境损害评估案例分析及应用

近年来,随着我国经济的高速发展,林地生态环境损害事件日益增加。不同类型的生态系统或同一生态系统在不同区域所提供的生态服务功能侧重均不同,鉴定评估林地生态系统的环境损害价值时应选用不同的测算方法。通过阐述理论公式法和实际监测法的原理和适用范围及其在生态环境损害评估中的应用,并对量化过程中参数的选取原则与方法进行说明。结合案例分析非法占用退耕还林地导致的生态环境损害范围和程度,计算出2012年~2019年的生态环境损害价值量为205万元。研究退耕还林地生态环境损害典型案例,并将其推广应用于小规模普通林地,对林地生态环境损害案件的鉴定评估环节具有重要引领作用。

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。

Farmland to Forest Conversion Suspended

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

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)。

2022年广西林草湿地图斑监测底图处理方法

森林、草原、湿地图斑监测底图的完善是2022年森林、草原、湿地图斑监测工作的基础和前提。针对国家下发的监测底图存在的共性问题和广西地方管理的需要,提出监测底图处理思路和手段。根据广西2022年林草湿图斑监测工作操作细则要求,基于ArcEngine二次开发技术开发辅助处理插件,实现不同调查单位监测底图统一处理。

基于退耕还林工程的生态环境质量动态变化研究——以云南兰坪县为例

2014年云南省怒江傈僳族自治州(简称怒江州)正式启动新一轮退耕还林还草工程,为探讨该轮退耕还林工程对怒江州兰坪白族普米族自治县(简称兰坪县)生态环境质量的影响,选择退耕还林工程实施前(2013年)、实施中(2017年)和实施末期(2020年)3个时间,基于遥感生态指数模型,选取绿度、干度、湿度和热度4个指标,运用主成分分析法对兰坪县2013—2020年的生态环境质量动态变化进行研究。结果表明:1)2013—2020年兰坪县生态环境质量处于上升趋势,中排乡、石登乡和河西乡的生态环境质量改善较为明显;2)2013—2020年,75%以上区域的生态环境质量等级保持不变,其他区域的生态环境质量等级呈小幅度变化,生态环境质量变好的区域面积要大于生态环境质量变差的区域面积;3)退耕还林斑块的生态环境质量提升程度要高于退耕还林2 km缓冲区以及整个研究区的生态环境质量提高程度,退耕还林工程对生态环境质量的改善具有显著影响,可通过进一步推进退耕还林工程来改善兰坪县的生态环境质量;4)研究区潜在的退耕区主要分布在中排乡、石登乡、营盘镇和兔峨乡4个乡镇,其可作为进一步退耕还林的重点区域。

新一轮退耕还林还草工程对土地利用效率的影响——基于黄河流域的实证研究

[目的]分析新一轮退耕还林还草工程实施对黄河流域土地利用效率的影响机制与政策效果,为深刻理解土地利用效率与持续推进退耕还林还草工程提供理论参考。[方法]以黄河流域新一轮退耕还林还草工程政策实施作为自然实验,采用包含非期望产出指标的Super-Window-DEA模型测度土地利用效率,采用双重差分模型与中介效应模型分析政策效果与传导途径。[结果](1)2009—2020年黄河流域69个城市的土地利用效率略有下降,上游(0.546 5)和下游(0.419 9)的土地利用效率高于中游(0.279 5);(2)新一轮退耕还林还草工程显著抑制了土地利用效率的提高,且政策的负向影响存在异质性,同时,经济发展和人口密度也分别促进和抑制土地利用效率;(3)耕地所占比例与财政支出是新一轮退耕还林还草工程影响土地利用效率的中介变量,且耕地比例是部分中介。[结论]建议在肥力较差、劳动力投入匮乏的土地上推进退耕还林还草工程,鼓励黄河流域各城市开展未利用土地的开荒复绿工作,后续退耕还林还草工程实施过程中根据流域之间土地利用的不同功能开展黄河流域上中下游之间、流域内城市之间的生态补偿,并充分借助信贷资金,引入生态产业化发展,推动绿色产业升级,探索退耕还林还草工程生态补偿的新模式。

国有林区森工企业土地利用动态变化研究

基于遥感数据和GIS技术,以龙江森工集团和伊春森工集团所属40个国有森工企业为研究对象,剖析不同时期土地利用类型动态变化,结合土地利用转移变化规模和方向的时空差异,探讨国有林区土地利用变化与经济社会发展转型新形势、新问题之间的关系。研究结果表明:⑴2006—2019年间黑龙江省国有林区天然林生态保护修复成效显著,林地面积增加了3.379 185万hm~2,动态度达到29.48%;⑵2014—2018年土地利用类型间转移最为频繁,除林地、水域和未利用地外,所有土地都存在用地竞争;⑶2006—2020年生态用地向建设用地转出面积约是建设用地向生态用地转出面积的2.10倍;⑷伊春森工集团的土地利用转移变化程度比龙江森工集团更稳定;⑸生态用地增加较多的国有森工企业总产值相对更高。

多源土地利用/覆被产品在黄土高原应用和精度评估

为准确掌握黄土高原土地利用/覆被的时空格局,基于6种不同来源的土地利用/覆盖数据产品,MCD12Q1,ESA-CCI-LC,GlobeLand30,GLASS,CAS-LUCC和ChinaCover,开展了黄土高原地区退耕还林(草)实施以来土地利用/地表覆被时空格局和转类特征的研究,对不同来源数据产品的精度进行了验证分析。结果表明:(1)分类特征和变化趋势上,MCD12Q1和GLASS产品与其他产品的差异最大,其次为ESA-CCI-LC产品,GlobeLand30,CAS-LUCC和ChinaCover产品的差异相对较小。(2)除MCD12Q1产品外,不同来源土地利用/覆被产品各类型面积随时间变化趋势基本一致。(3)空间转类上,GLASS产品与其他产品的差异最大,解译类型明显错误;其次为MCD12Q1产品,转林类和转草类也存在明显错误,退耕还林(草)特征表现不明显;ESA-CCI-LC和GlobeLand30在黄土丘陵沟壑区退耕还林(草)的转类特征表现不足;CAS-LUCC和ChinaCover退耕还林(草)特征明显。(4)抽样精度上,GlobeLand30,CAS-LUCC,ChinaCover产品的总体精度最高,分别为86.61%(K=0.84),91.68%(K=0.90),89.45%(K=0.87);其次为ESA-CCI-LC(73.83%,K=0.69);MCD12Q1,GLASS产品的精度最低,分别为59.43%(K=0.51),36.31%(K=0.24)。(5)土地利用/覆被多源数据产品的融合有利于提高产品的精度,与融合前产品GlobeLand30,CAS-LUCC和ChinaCover相比,融合产品总精度可提高了2.25%~7.30%。综上,CAS-LUCC产品的精度最高,且2000—2010年退耕还林(草)表现与实际较为相符。

宁夏退耕还林还草成果巩固问题探讨

退耕还林还草是中共中央、国务院在20世纪末着眼中华民族长远发展和国家生态安全作出的重大决策。23年来的退耕还林还草工程实践取得了巨大的生态、经济和社会效益,赢得了社会各界赞誉。“十四五”以来,国家基于粮食安全和耕地保护考虑,已将工程重心转移到巩固已有建设成果上来。文中基于宁夏回族自治区退耕还林还草工程现状,总结退耕还林还草成果巩固的经验做法,梳理分析现存问题,并提出今后推动退耕还林还草高质量发展的建议:1)深挖后续产业发展潜力,促进“以林养林”;2)合理优化退耕林地树种组成和植被配置模式,改善退耕林质量;3)提高生态效益补偿标准;4)稳定基层管理队伍。

山东省耕地保护背景下标注耕地属性林地处置及影响探讨

山东省因耕地保护目标压力巨大,“林粮争地”矛盾日渐突出。本文以茌平区、莒县、莱阳市为例,对标注“即可恢复”“工程恢复”耕地属性林地保留或调出范围进行研究划定,统计相关数据,得出结论:不同县市区约有10%~50%的林地属于在农民依法承包经营的耕地上自主种树的,按照“非粮化”要求及耕地保护目标需求,调出林地进行复耕后,3个县市区森林覆盖率随之降低0.64%~9.17%。

退耕还林地栽植山杏红松对土壤理化性质的影响

以龙江县两种主要退耕还林地——樟子松嫁接山杏林地和红松林地为研究对象,以农田地作为对照,采用主成分分析法明确影响土壤状况的主要指标,对各样地进行综合评价,分析土壤理化性质,为该地区植被恢复及土壤修复提供科学依据.结果显示:各样地土壤容重、土壤pH随土层深度增加而增大,土壤有效蓄水量、土壤总孔隙度、土壤毛管孔隙度及土壤有机质含量呈减少趋势;农田地土壤有效蓄水量、土壤总孔隙度、土壤非毛管孔隙度、土壤pH、土壤有机质含量均低于山杏林地及红松林地;试验区域土壤理化性质综合评分由高到低为红松林地>山杏林地>农田地.农田地退耕对改善土壤状况具有一定促进作用.

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。