A Methodology Framework for Regional Land-use Change Studies based on Landsat TM images: A Case Study in Northeast China

Land-use change is an important aspect of global environment change. It is, in a sense, the direct result of human activities influencing our physical environment. This paper analyzed the land-use change in Northeast China during 1985-2000 based on Landsat TM images. It divides Northeast China into five land-use zones based on the dynamic degree model of land-use: woodland/grassland-arable land conversion zone, dry land-paddy field conversion zone; urban expansion zone, interlocked zone of farming and pasturing and reclamation and abandon zone. The findings include the obvious increase of cropland area, paddy field and dry land increased by 75 and 276 thousand hm2 respectively; urban areas expanded rapidly, areas of town and rural residence increased by 76.8 thousand hm2; areas of forests and grassland decreased sharply with the amounts of 1399 and 1521 thousand hm2 respectively; areas of water body and unused land increased by 148 and 514 thousand hm2 respectively. This paper also discusses the driving     

洞庭湖区不同利用方式下农田土壤有机碳含量特征

土地利用方式是影响土壤有机碳含量和动态的重要因子之一。其利用方式的改变必将引起土壤有机碳含量发生相应的变化。在洞庭湖腹地选取典型样区,通过调查走访和密集取样,分析了不同土地利用方式（旱地、水旱轮作地、一季稻水田和双季稻水田）下623个农田耕层土样有机碳含量。结果表明,研究区内土壤有机碳含量高低顺序为双季稻水田（28.12 g/kg） > 一季稻水田（27.03 g/kg） > 水旱轮作地（24.79 g/kg） > 旱地（17.96 g/kg）,其差异均达到极显著水平（P < 0.01）。土地生产力、秸秆还田量和土壤水文状态是导致不同利用方式下耕层土壤有机碳含量差异的主要原因。进一步分析表明：加强作物秸秆还田（土）、提高土地复种指数、增加地表覆盖是维持和提高洞庭湖区耕作土壤有机碳含量的可行措施,尤其是旱作土壤。     

东北农牧交错生态脆弱区可持续发展研究

生态脆弱区是经济落后、人民生活较为贫困的地区．是可持续发展领域重点研究地区之一。实现生态脆弱区可持续发展管理的重要基础之一是对其发展现状进行综合测度。以我国典型生态脆弱区-东北农牧交错区为例．运用所建立的指标体系对阜新、通辽、赤峰等典型样点地区的可持续发展现状进行评估．对引致区域可持续发展现状的主要原因进行剖析；对1990年和2002年两个不同时段的可持续发展状态进行对比分析。结果表明资源与环境状况是影响区域可持续发展的关键因子．经济发展是提高可持续发展能力的根本保证．社会、人口、科技子系统对区域可持续发展具有重要作用。基于对上述问题的分析．提出东北农牧交错区可持续发展能力建设的几点对策。     

稻虾共作快速发展背景下潜江耕地时空变化特征分析

虾稻共作综合种养模式近年来在长江中下游地区快速发展，探索虾稻共作对农业土地利用的影响，对于科学调控虾稻田发展、确保粮食和生态双安全具有重要意义。该研究以虾稻共作模式发源地——湖北潜江市为研究区域，利用空间分析和破碎度指数方法，分析虾稻共作模式快速推广下潜江市农业土地利用时空格局变化。结果表明：（1）近20年来，耕地时空格局变化过程是以园林办事处（主城区）为中心的建设用地向西至广华镇、南至杨市镇不断扩张，耕地转为新增建设用地达28.64 km2，约18.59 km2耕地转换为水域；（2）耕地格局呈现破碎化，主要由城市发展过程中建设用地扩张占用耕地，以及虾稻田快速发展后造成；（3）虾稻田主要由水田转换而来，部分旱地及水域也转换为虾稻田。虾稻田的不断扩张，特别是旱地和水域转换为虾稻田，一定程度上带来耕地破碎化。因此，在我国农业劳动力不足、农民收入不高和种地积极性不强等因素下，未来虾稻田种植模式对耕地利用具有较好的潜力和空间，但也需要重点关注虾稻共作模式的可持续发展，重点基于水田发展虾稻田种养模式。     

Development of a land-use forecast tool for future water resources assessment: case study for the Mekong River 3S Sub-basins

Land-use change is one of the major factors that alter local and regional hydrology. For areas experiencing fast expansion of urban and agriculture areas, land-use changes often adversely affect stream flow and water resources at the local and watershed scale. The Sekong, Sesan, and Srepok (3S) Sub-basins are a part of the Lower Mekong River Basin and include land in Cambodia, Lao People’s Democratic Republic (Laos), and Viet Nam. The region is experiencing a dynamic land-use transition because of rapid changes in its economy, society, and environment. Major land-use changes include deforestation of native rain forest, expansion of agricultural and urban areas, and expansion of commercial plantation such as rubber trees. These land-use alterations have affected local and regional hydrologic processes, resulting in stream flow shortages during the dry season and flash flooding due to deforestation. In this research, deforestation in the 3S Sub-basins over the period 1993–1997 was analyzed using multi-logistic regression. The regression analysis indicated that density of agricultural cells within a 5-km radius from each forest cell and slope strongly affected the deforestation process. A land-use forecast model to simulate deforestation and urbanization sites was developed in GIS based on local land-use change trends. The model was applied to 2003 land use to forecast 2033 land use and future water demand, which was further compared with present stream flow measurements during the dry season at various places in the region. The entire approach from the land-use forecast to its impact assessment on stream flow could help local stakeholders understand watershed-wide future water resources risks and develop future water resources plans. With the 3S Sub-basins being used as a case study area, this article presents a land-use forecast tool; simulated 2033 land-use and water demand; and the estimation of the impact of the forecasted future water demand on the local stream flow.     

流域土地利用变化的长周期水文效应及管理策略

长周期水文效应作为不同强度暴雨事件的综合反映，对流域规划和管理决策非常重要。以太湖地区蠡河流域为研究区，通过解译1984年、1995年和2000年3个时段TM/ETM获得土地利用分布地图，分析其土地利用变化的模式，并基于研究区30年的降水序列，应用长周期水文分析模型L-THIA（Long-Term Hydrologic Impact Assessment），计算3个时段土地利用特征对暴雨地表径流的影响，分析不同土地利用类型水文效应的敏感性，在此基础上总结了减少流域水文效应的土地利用管理策略。分析结果显示，该区土地利用有明显变化，主要表现为水田、旱田向建筑用地的转化，从1984年到2002年，城镇及居民地扩展占流域总面积的4.199 4 ％，地表径流量增加了6.170 ％，不同土地利用方式的水文效应有较大差别，林地、湖滩湿地的敏感性最大，其次是水田和旱田。     

升金湖湿地时空演变对越冬鹤类种群动态的影响

升金湖湿地是我国主要的鹤类越冬栖息地之一。研究升金湖湿地时空变化对越冬鹤类种群动态的影响在湿地生态环境改善、鹤类种群恢复等方面具有重要参考价值。对1986～2015年升金湖湿地白头鹤（Grus monacha）、白鹤（Grus leucogeranus）、灰鹤（Grus grus）及白枕鹤（Grus vipio）种群数量的变化趋势分别进行了曲线拟合；结合升金湖湿地1986~2015年间8期遥感影像分析了研究区土地利用/覆盖的时空变化；并探讨了湿地时空变化与越冬鹤类种群数量变化之间的相关性。结果表明：1986~2015年间，研究区的景观格局发生了较大变化，草地、水田、滩涂及其他用地的面积总体呈增加态势，而林地、旱地、水域及芦苇沼泽地面积总体呈减少的态势；4种鹤类的数量总体呈下降趋势，曲线拟合中白鹤和白枕鹤种群数量变化的趋势方程拟合度较高；芦苇沼泽地及水域面积变化与越冬鹤类种群数量呈显著的正相关关系，而草地、滩涂及水田的面积与鹤类种群数量呈较强的负相关关系；其他景观面积变化间接对鹤类种群数量产生影响。 关键词： 时空变化；鹤类；遥感影像；土地利用/覆盖；升金湖     

汉江流域土地利用变化及空间格局分析

土地利用变化是人类活动对自然环境施加影响的显著表现形式,已成为全球环境变化研究的重要内容。基于遥感和地理信息系统技术,利用三期Landsat TM图像的解译成果,分析了安康市1985～2000年土地利用变化的结构特征及其空间差异格局。研究表明,近15年来,安康市土地利用转移量主要发生在耕地、林地、草地和水域之间．建设用地和未利用土地的转移趋势不明显。三个时段内各土地利用类型的净变化量差异比较明显。1985～1995年．耕地变化以转入为主,其中由草地转入的比重最大,占耕地总转入量的96．02％。1995～2000年,耕地以大量转出为主,共有1503．21hm2的耕地转为其它用地,其中转向林地和草地的量占耕地总转移量的比例分别是15．46％和78．77％。在行政区尺度上各种用地类型的净变化量分布比较均衡,而在垂直带空间尺度上耕地、林地和草地的净变化随海拔高度的分异较为明显。大致以1600m为界,耕地随海拔高度升高而递减,林地、草地随海拔高度升高而递增．     

无锡市城镇化进程中土地利用变化及其环境效应

20世纪90年代,城市用地扩展是我国区域土地利用演化的主导过程,城市土地利用所引起的地表景观格局的变化又是引起地表各种地理过程变化的主要原因。基于Landsat TM图像解译的土地利用的动态图斑,分析了20年代90年代无锡市土地利用的变化态势。研究表明,土地利用变化主要体现为耕地向林地、水域、建设用地的转移．林地向耕地、建设用地的转移,以及草地、水域向建设用地的转移;20世纪90年代中后期,国家颁布的一系列基本农田保护和“退耕还林还草”的政策法规,在一定程度上限制了大量耕地被建设占用的趋势。土地利用快速变化也导致明显环境效应．主要表现为水环境的恶化和现代“城市病”等方面。因此,加强土地规划管理、合理利用土地资源、重视能源开发与基础设施建设,应成为今后区域土地资源开发、利用与保护的重点与方向。     

洞庭湖区土地利用变化对地表产流的影响分析

利用20世纪80年代末期和90年代末期获取的陆地资源卫星图像,通过GIS分析方法,对洞庭湖区近10年的土地利用／覆盖变化进行了统计分析。并以1996年7月日降雨资料分别计算了1989年和1999年土地利用状况下区域的产水量。结果表明：洞庭湖区10年间土地利用变化的主要趋势是耕地面积减少和建设用地、水域面积的增加。土地利用的主要转化方式有水田转化为建设用地、水田转化为水域、林地转化为建设用地以及旱地转化为建设用地。同样的降雨条件下,洞庭湖区1999年下垫面状况下的产水量比1989年多206×105 m3,建设用地面积的增加是这一时期产水量增加的主要原因。土地利用的变化影响汛期产水量和汇流速度,加强洪泛区的土地管理,合理控制调整土地利用状况是减轻洪涝灾害威胁的有效手段。     

城乡交错区耕地分区管护及生态补偿模式研究——以上海市浦东新区为例

基于土地评价和立地条件评估(Land Evaluation and Site Assessment, LESA)框架构建以耕地自然质量、生态敏感性、区位条件、耕作条件和土壤环境安全风险组成的指标体系,以决策树归纳法将浦东新区耕地划分为工业污染、生态农业、轮作休耕、农业连片、休闲农业和非农转化6类管护区,根据各区管护重点提出规模经营及绿色生产、休闲观光及农田保育、非农管控及发展限制型耕地生态补偿模式。上海市浦东新区耕地自然质量优良,约50%的耕地可规模经营及连片生产,但仍有10%左右的耕地面临着工业污染和非农占用的风险。建议对以稳产高产和生态协调为目标的农业连片区和生态农业区采取规模经营及绿色生产型生态补偿模式,对发展农业生产新形态的轮作休耕区和休闲农业区采取休闲观光及农田保育型生态补偿模式,对非农化风险较高的工业污染区和非农转化区采取非农管控及发展限制型生态补偿模式。     

荆江分洪区土地利用时空动态变化研究

通过1986、1996 和 2002 年3期 Landsat TM＼ETM 遥感图像,分析得到荆江分洪区 1986～1996年 和 1996～2002 年土地利用变化情况及土地利用转移矩阵。17年来,荆江分洪区土地利用结构和强度发生了重大的变化。主要表现为：城乡居民及建设用地通过吞食大量耕地、林地而得到迅速增加,年均增幅达到9.66％;林地大规模减少,主要向农业用地和建设用地转变;由于研究区域水旱轮作,水田、旱地年际变化很大,主要根据市场行情决定作物种植。水域和滩涂也逐年减少,年均减幅分别为1.85％和3.34％。土地利用变化的主要驱动因素是人口的增长和经济的发展以及政策制度的激励和导向作用。根据荆江分洪区在整个长江防洪工程中的总体地位,根据分洪区应有别于非分洪区的政策和法规,采取国家扶持和引导,制定合理的规划和经济发展政策,调整区内土地利用结构和控制人口增长,实现分洪和经济可持续发展。     

Intensification level of rice farming in Myanmar: implication for its sustainable development

This study aims to estimate the intensification of rice farming in Myanmar particularly due to chemical fertilizer application, using farm-level data obtained from field surveys conducted in the 2000s. Relatively high-input rice farming was found in dry season crop in the delta zone and the double crop in well-irrigated lowlands of the central dry zone. The chemical fertilizer used there was about 88–159 kg NPK (nitrogen, N; phosphate, P₂O₅; and potash, K₂O) ha⁻¹ (76–110 kg nitrogen (N) ha⁻¹), and the average paddy yield ranged from 2.8 to 3.5 ton ha⁻¹. On the other hand, nutrient input in survey sites of rain-fed lowland was between 11 and 53 kg NPK ha⁻¹ (5 and 36 kg N ha⁻¹), and the yield ranged from 1.1 to 2.3 ton ha⁻¹. The national average of paddy yield and nutrient input of fertilizer was roughly estimated to be around 2.4 ton ha⁻¹ and 60 kg NPK ha⁻¹, respectively. A gap was observed between these calculated values and the official statistics. A comparison of fertilizer use efficiency for rice production in Myanmar with that in China and Vietnam has shown that the efficiency in Myanmar has not declined to an inappropriate level even in its intensive ones. Rice production in Myanmar has room for increasing the yield by capital intensification. Nevertheless, considering its sustainability as well as productivity, further intensification in rice farming technology in irrigated lowlands of Myanmar may neither be the best nor the only way.     

不同地貌类型区城镇扩展对土地利用景观格局的影响

基于RS和GIS的支持，以名山县为研究案例，分析与探讨西部经济以农业为主地区城镇扩展的时空特征和不同地貌类型下土地利用景观格局，以期为城镇规划及区域城镇可持续发展提供决策支持。结果显示：1975 ~ 1999 年土地利用类型在不同地貌区的分布格局变化显著。林地面积大幅减少，分布区域向海拔较高地区收缩。居民及建设用地在低丘区增长较快，城镇用地大幅增加，成为影响研究区景观格局的重要要素。农业生产活动向地势较高的区域扩展，中丘区成为农业生产的主要场所，水田和旱地成其主要土地利用方式。高丘区旱地分布面积占首位；园地在低山区分布面积有所增加。1999~2005 年基本维持1999年景观格局，居民及建设用地继续增长，尤其在低丘区表现明显；低丘和中丘区斑块总数减少，各景观要素平均斑块面积增加，形状指数和分维数降低；高丘、低山区水田、旱地减少，园地面积增加.     

论水稻土肥力进化与土壤质量——以太湖地区为例

太湖地区是我国古老农业区之一。在六七千年之前先民已开始种植水稻 ,随着耕作培肥措施不断加强 ,与土壤肥力进化同步伴随着耕作轮作制的不断演进 ,由轮荒———沤田———水旱轮作———三熟制的变化 ,土壤基础肥力稳步提高 ,稻麦单位面积产量逐年上升。该区水稻土历经数千年的耕肥与平田整地等人为活动 ,在起源土壤背景上发育成五类水稻土 ,这五类水稻土经过培肥改良均达到水旱轮作高产稳产阶段 ,尽管地力上还存在不同程度的差异 ,这不能不说是人为定向培育的成果。在一般情况下 ,土壤质量是由土壤肥力决定的 ,基础肥力高低是农业生产优质高产低耗的关键 ,在评价土壤质量时必需首先予以关注。当然 ,随着工业的发展 ,土壤污染所波及的农产品超标问题 ,也应在评价土壤质量时予以关注 ,并作为评价因素在综合评价体系中占有应有的份量     

经济发达区不同土地利用方式下土壤中镉的含量特征——以江苏省昆山市为例

通过对江苏省昆山市高中低产水稻田、菜地、园地和抛荒地等土地利用类型98个土壤样点的检测分析，探讨了不同土地利用方式对土壤镉浓度含量的影响。研究结果表明，高中低产水稻田、菜地、园地土壤镉浓度都超过土壤背景值（0.110 mg/kg）。6种土地利用方式中，低产水稻田土壤的镉浓度最高，其次分别为中产水稻田、园地、菜地、高产水稻田和荒地。与土壤标准值（0.20 mg/kg）相比，中产水稻田有20%样点超标，低产水稻田、园地、菜地分别有18.75%、11.11%、9.09%样点超标，而高产水稻田和荒地没有超标样点。工业废物排放和磷肥的使用可能是影响不同土地利用类型下土壤镉浓度的重要原因，应该引起重视。     

Correlation between Urban Land Change Process and Socioeconomic Development since the 1980s in Jiangsu Province

Abstract

Studying the process and characteristics of urban land change in different phases of urbanization and different economic development is much important for understanding urban land change and management at a macro level. Taking the example of Jiangsu Province, the present paper studied the correlation between urban land change process and socioeconomic development from 1981 to 2003 on the basis of statistical data. The results showed the following three aspects. First, urban land area has changed periodically and the research duration can be divided into two periods: from 1981 to 1994 and from 1995 to 2003. In each period, the changing trend is the same, i.e. slow at first and then quick. Studying from the comprehensive change status, the characteristic of fluctuant change is significant with three acute change pinnacles in 1988, 1991 and 2002 which were corresponded to turning point years of economic development phases of Jiangsu Province respectively. Second, the synchronization between urban land change and urbanization level change is not strict. With the evolution of urbanization phases, the change pace of urbanization level increased remarkably, but urban land change rate did not increase significantly accordingly. Third, the area of urban land has exponentially increased with the increase of per capita GDP. In different economic development levels classified by per capital GDP, land resource cost for economic development is different, respectively 29.01 hm², 26.34 hm², 26.22 hm², and 11.14 hm² for the increase of 100 million RMB GDP when the per capita GDP is under 1000, 1000–2000, 2000–5000 and over 5000 RMB.     

Migration and reclamation in Northeast China in response to climatic disasters in North China over the past 300?years

Climatic disaster-induced migration and its effects on land exploitation of new settlements is a crucial topic that needs to be researched to better understand the impact of climate change and human adaptation. This paper focuses on the process and mechanism of migrant–reclamation in Northeast China in response to climatic disasters over the past 300 years. The research used comparative analysis of key interlinked factors in this response involving drought/flood events, population, cropland area, farmer revolts, administrations establishment, and land reclamation policies. It draws the following conclusions: (1) seven peaks of migrants–reclamation in Northeast China were evident, most likely when frequent climatic disasters happened in North China, such as the drought–flood in 1851–1859, drought in 1875–1877, and drought 1927–1929; (2) six instances of policy transformation adopted to cope with extreme climatic events, including distinctive examples like changing to a firm policy prohibiting migration in 1740 and a subsequent lifting of that prohibition in 1860; and (3) the fast expansion of the northern agricultural boundary since the middle of the nineteenth century in this area benefited from a climate change trend from a cold period into a warm period. Altogether, over the past 300 years, extreme climatic disasters in North China have deepened the contradiction between the limited land resources and the rapidly increasing population and have resulted in migration and reclamation in Northeast China. Climate, policy, and reclamation constructed an organic chain of response that dominated the land use/cover change process of Northeast China.     

Modeling changes in paddy rice sown areas in Asia

Paddy rice fields in Asia account for over 90% of global total rice cultivation area, and the major rice-producing countries of Asia account for over one-half of the world’s population. Monitoring and understanding the dynamic changes in paddy rice agriculture in Asia are very important for agricultural sustainability, food and water security, and greenhouse gas emissions. This paper presents a crop choice decision model that dynamically simulates future changes in sown areas of paddy rice in Asia. This model was developed under the framework of Action-in-Context (AiC) with the aim of understanding land users’ decisions on crop choices among a set of available alternatives using a crop utility function. Empirical validation for the model conducted after model construction indicated the reliability of the model for addressing the complexity of current agricultural land-use change and its capacity for investigating long-term scenarios in the future. Finally, the model was applied for future scenario analysis over a time frame of 30 years with 5-year increments, beginning from the year 2005. The simulation results provided insights into rates and trajectories of changes in Asian rice areas over the test period, with the resulting implications for future agricultural sustainability in Asia. These outcomes can improve understanding of projected land-use changes and explain their causes, locations and consequences, as well as providing support for land-use planning and policy making.     

Study on Sustainable Development in Vulnerable Eco-areas

Abstract

The vulnerable eco-area is one of the important research targets in the field of sustainable development. It is the requirement of building a well-off society in an all-round way that we should study more on the vulnerable eco-areas, deal with the relationship between environmental protection and economic development, speed up the economic development in these areas and increase the living standard of the local people. This paper puts forward the countermeasures of environment—economy coordination, on the basis of the recognition of eco- environment features and social economic conditions in the vulnerable eco-areas of China, in view of the progress in sustainable development studies of the vulnerable ones, taking the transitional areas of farming and pasturing in northeast China as an example to study the regional environment vulnerability.