Accounting for carbon stocks in models of land-use change: an application to Southern Yucatan

To assess the impact of land-use change on carbon stocks, we apply a new methodology, linking ecological and economic modeling, to southern Yucatan, Mexico. A spatial econometric multinomial logit model of ten land-cover classes is estimated (four primary forest categories, three secondary growth categories, an invasive species, and two agricultural land-cover categories), using satellite data on land cover, linked with census socioeconomic data and other biophysical spatial data from 2000. The analysis is novel in that it is the first attempt to link detailed satellite data on land use, with on-the-ground estimates of carbon stocks in a spatial econometric model of land use. The estimated multinomial logit model is then used with two scenarios of future economic growth (“low growth” and “high growth” changes in population, agricultural land use, market access, and education levels) in the region to predict land-cover changes resulting from the economic growth. The per hectare carbon (C) stocks in each land-cover class are derived from previously published estimates of biomass from field sampling across the study region. We consider aboveground-only, aboveground plus soil, transient and non-transient pools of carbon. These estimates are scaled up to the total area in each class according to the predictions of the model baseline and the two development scenarios. Subsequently, the changes in carbon stocks resulting from the predicted land-cover changes are calculated. Under the low growth scenario, carbon stocks declined by 5%; under the high growth scenario, losses were 12%. Including soil C, the proportional losses were lower, but the absolute amount lost was more than double (to 6 Tg C under the low and almost 15 Tg C under the high-growth scenario). This methodology could be further developed for applications in global change policy, such as payments for environmental services (PES) or reduction in emissions from deforestation and degradation (REDD).     

基于邻接关系的土地利用变化空间关联规则研究

空间关联规则可在海量空间数据中挖掘出空间对象之间相互作用、空间依赖、因果或共生的模式。将空间关联规则方法引入土地利用变化时空特征分析中,以浙江省桐庐县2004~2009年的两种典型地类变化(城镇用地的转入、耕地的转出)为例,结合GIS的空间统计和空间分析功能,首先通过土地利用转移矩阵分析土地利用面积变化的整体情况,再采用经典Apriori算法挖掘这两种典型地类变化与其周边邻接的地类变化间的关联性规律。研究表明:(1)桐庐县土地利用呈现明显的非农化趋势,这主要归因于城镇化进程以及其作为特色发展的生态建设;(2)城镇用地的发展主要依靠耕地和农村居民点的转型,表现为集中连片的扩展方式,且城镇用地与交通水利建设用地的发展具有明显的共生现象;(3)耕地的同种转变类型在空间上呈现连片集聚分布,且耕地发展易受相邻地类的驱动或制约,尤其是林地和农村居民点。空间关联规则挖掘能够定量分析在空间邻接的情况下地类间的转变倾向以及变化的关联规律,为土地利用变化时空分析提供有用信息。     

A landscape approach for quantifying land-use and land-cover change (1976–2006) in middle Himalaya

With the growth of socio-economic activities, natural land cover is being modified for various development purposes. This has increased the rate of land-use and land-cover changes (LULCC), and thus, affecting the overall ecosystem health. LULCC mapping is an important tool for land management and monitoring. This paper presents LULCC analysis using remotely sensed data integrated into a Geographic Information System (GIS). LULCC was quantified using Markov analysis, and the associated probability of change for each class was predicted. Landscape metrics were also used to quantify the spatial and temporal changes in the area. The unique combination of these techniques support the conclusion that with increasing human activities, (1) the deforestation rate has increased, (2) forested areas have become increasingly fragmented, and (3) the forested areas have the highest probability of getting converted to some other land-use and land-cover (LULC) class.     

Sprawl matters: the evolution of fringe land,natural amenities and disposable income in a Mediterranean urban area

We investigate the relationship between land-use changes (1987–2007) and the spatial distribution of the average declared income of resident population in a southern European metropolitan region (Athens, Greece) as a contribution to the analysis of suburbanization processes in the Mediterranean region. To demonstrate that urban expansion is accompanied with multiple modifications in the use of the surrounding non-urban land, we developed a computational approach based on spatial indexes of landscape configuration and proximity as a result of changes in the local socio-spatial structure. Diversity in the use of land surrounding built-up parcels in the Athens’ metropolitan region increased significantly between 1987 and 2007, reflecting a progressive fragmentation of the exurban landscape. The percentage of forests and (high-quality) natural land surrounding built-up parcels increased from 8.1 to 9.4 % between 1987 and 2007. The reverse pattern was observed for (low-quality) sparsely vegetated areas, declining from 65 to 47 %. Large built-up parcels were surrounded by a higher percentage of natural land than small parcels. The largest increase over time in forest and natural land surrounding built-up parcels was observed in municipalities with high per capita declared income, and the reverse pattern was observed for sparse vegetation. Our results demonstrate that scattered urban expansion determines a polarization in suburban areas with high-quality and low-quality natural amenities. Sprawl increases economic inequality and socio-spatial disparities contributing to a spatially unbalanced distribution of natural amenities with higher consumption of high-quality land.     

Changing land use/cover patterns and implications for sustainable environmental management in the Irangi Hills,central Tanzania

This article examines the changes in land-use/cover types in the Irangi Hills, central Tanzania during the last 45 years and how such changes have influenced environmental and agricultural sustainability in the area. The spatial and temporal changes of land-use/cover were analysed through aerial photographs interpretation. Local perceptions and experiences of changes were addressed through household interviews and field observations. Results from this study show that during the last 45 years open and wooded grasslands, and other tree-cover types covered about 40% of the land area, ranging from 29% in 1960 to 43–45% between 1977 and 1992. Also, during the same period both the total area and spatial distribution of cultivated fields varied greatly. The cultivated area increased from 31% in 1977 to 35% in 1992, mainly due to agricultural expansion into areas formerly used for grazing and in sandy watercourses that shrunk by 55% between 1977 and 1992. The spatial distribution of the different land-use/cover types is influenced by variations in the scale of soil erosion and soil-conservation initiatives implemented in the Irangi Hills since the early 1970s. However, with increasing pressure on the land, and the declining capacity of the soil conservation authority, sustaining agricultural production in the area remains a major challenge.     

Land-use change and its socio-environmental impact in Eastern Ethiopia’s highland

The Alemaya district (Eastern Ethiopian highlands) is characterized by undulating physiographic features with arid, semi-arid, and humid climatic conditions. This study evaluated socio-environmental changes in land use and land cover during 1985–2011. Screen digitization on remotely sensed data (i.e., Landsat images from 1985 to 2011) was performed to produce 10 classes of land use and land cover. Then, final land-use maps were prepared using a geographic information system following field verification and accuracy assessment. The drying of water bodies, including the prominent lakes Alemaya, Adele, and Tinike, had been the most important environmental change observed. Degraded land, marsh, perennial cropland, and residential areas increased by 37, 438, 42, and 190 %, respectively, whereas grassland, plantation, shrubland, and temporal cropland decreased by 64, 11, 63, and 29 %, respectively. The increase in land degradation (+37 %), the other major observed problem, has made large areas unsuitable for agriculture and has reduced crop productivity. These land-use and land-cover changes have affected both the environment and the livelihoods of local residents; especially the issue related to land degradation requires urgent attention.     

湖北省近期土地利用变化的遥感分析

土地利用，覆盖变化研究是全球变化研究的前沿和热点之一。采用遥感、GIS一体化技术．利用1989～1990年和1999～2000年获取的陆地资源卫星图像，建立了湖北省近10年来两个不同时期的同比例尺土地利用动态变化数据库，并对变化的时空特征进行了分析。结果表明，耕地减少了0．68％，林地减少了0．18％，各类建设用地总计增加了。7．92％．水域面积增加的幅度为3．01％。土地利用与土地覆盖变化的转型主要发生于上述4类之中．尤其是耕地与水域相互之间的转变比较频繁。动态度计算表明，土地利用变化最快的区域均处于大中城市及其周边地区；江汉平原、鄂东的大部分地区及鄂西的宜昌．土地利用变化较快；鄂西山区绝大部分、大别山区部分县及鄂东南幕阜山区的通山县，土地利用变化不大。     

Livelihoods and landscapes at the threshold of change: disaster and resilience in a Chiapas coffee community

In 2005, torrential rains associated with Hurricane Stan devastated farm systems in southern Mexico. We present a case study on the impacts of and responses to Hurricane Stan by coffee households in three communities in the highlands of Chiapas, Mexico, with the objective of illuminating the linkages between household vulnerability and resilience. We analyze data from 64 household surveys in a cluster analysis to link household impacts experienced to post-Stan adaptive responses and relate these results with landscape-level land-cover changes. The degree of livelihood change was most significant for land-constrained households whose specialization in coffee led to high exposure and sensitivity to Stan and little adaptive capacity. Across the sample, the role of coffee in livelihood strategies declined, as households sought land to secure subsistence needs and diversified economically after Stan. Nevertheless, livelihoods and landscape outcomes were not closely coupled, at least at the temporal and spatial scale of our analysis: We found no evidence of land-use change associated with farmers’ coping strategies. While households held strong attitudes regarding effective resource management for risk reduction, this knowledge does not necessarily translate into capacities to manage resilience at broader scales. We argue that policy interventions are needed to help materialize local strategies and knowledge on risk management, not only to allow individual survival but also to enhance resilience at local, community and landscape scales.     

Biophysical suitability,economic pressure and land-cover change: a global probabilistic approach and insights for REDD+

There has been a concerted effort by the international scientific community to understand the multiple causes and patterns of land-cover change to support sustainable land management. Here, we examined biophysical suitability, and a novel integrated index of “Economic Pressure on Land” (EPL) to explain land cover in the year 2000, and estimated the likelihood of future land-cover change through 2050, including protected area effectiveness. Biophysical suitability and EPL explained almost half of the global pattern of land cover (R ² = 0.45), increasing to almost two-thirds in areas where a long-term equilibrium is likely to have been reached (e.g. R ² = 0.64 in Europe). We identify a high likelihood of future land-cover change in vast areas with relatively lower current and past deforestation (e.g. the Congo Basin). Further, we simulated emissions arising from a “business as usual” and two reducing emissions from deforestation and forest degradation (REDD) scenarios by incorporating data on biomass carbon. As our model incorporates all biome types, it highlights a crucial aspect of the ongoing REDD + debate: if restricted to forests, “cross-biome leakage” would severely reduce REDD + effectiveness for climate change mitigation. If forests were protected from deforestation yet without measures to tackle the drivers of land-cover change, REDD + would only reduce 30 % of total emissions from land-cover change. Fifty-five percent of emissions reductions from forests would be compensated by increased emissions in other biomes. These results suggest that, although REDD + remains a very promising mitigation tool, implementation of complementary measures to reduce land demand is necessary to prevent this leakage.     

人工园林大面积种植区植被净初级生产力时空变化研究

云南西南地区自然资源丰富，近年来，随着社会经济的快速发展，橡胶、茶园和桉树等人工园林大规模种植主要占用了天然林和耕地，土地利用结构和空间布局发生了很大变化。为了探讨土地利用/覆被变化对植被净初级生产力（NPP）的影响，以人工园林大面积种植区西盟县为研究区，运用综合模型、CASA模型和MODIS产品（BIOME-BGC模型），对西盟县2000年、2005年、2010年和2015年各地类NPP的时间变化和空间分布特征进行分析。结果表明：（1）2000~2015年，CASA模型模拟的西盟县NPP呈先减少后增加的趋势，MODIS模型模拟的NPP值变化趋势与CASA模型一致，综合模型则呈现逐年增加的趋势；（2）西盟县NPP的空间分布形态从西至东均呈“低值-高值-低值-高值-低值”（“M”）变化，与西盟县水热资源的分布特征和土地利用/覆被变化有关，西盟县NPP空间变化主要集中于人工园林种植区；（3）3种模型中，CASA模型和MODIS产品（BIOME-BGC模型）比综合模型更适用于地形气候复杂多样的山区NPP的模拟计算，其中CASA模型空间精度更高。     

Combining remote sensing and household level data for regional scale analysis of land cover change in the Brazilian Amazon

Land cover change in the Brazilian Amazon depends on the spatial variability of political, socioeconomic and biophysical factors, as well as on the land use history and its actors. A regional scale analysis was made in Rondônia State to identify possible differences in land cover change connected to spatial policies of land occupation, size and year of establishment of properties, accessibility measures and soil fertility. The analysis was made based on remote sensing data and household level data gathered with a questionnaire. Both types of analyses indicate that the highest level of total deforestation is found inside agrarian projects, especially in those established more than 20 years ago. Even though deforestation rates are similar inside and outside official settlements, inside agrarian projects forest depletion can exceed 50% at the property level within 10–14 years after establishment. The data indicate that both small-scale and medium to large-scale farmers contribute to deforestation processes in Rondônia State encouraged by spatial policies of land occupation, which provide better accessibility to forest fringes where soil fertility and forest resources are important determinants of location choice.     

基于CLUE-S模型的重庆市主城区土地利用情景模拟

以重庆市主城区为研究区,采用120m×120m栅格大小的数据为模拟基准,借助CLUE-S模型、情景分析法、SPSS软件及ArcGIS10.1软件建立了数量变化和空间分布变化相结合的不同情景下土地利用/覆盖变化的动态模拟模型,并对研究区不同情景下的土地利用/覆盖动态变化进行了模拟,模型综合考虑各种宏观驱动因子与土地利用变化之间的关系,较全面地考虑了多种土地利用/覆盖变化驱动因子,并利用SPSS软件进行相关性分析,确定了各因子的回归模型,提高了模拟结果的精度,通过对已有数据的模拟及精度分析,整体模拟精度达86%以上,在一定程度上反映了该模型在研究高分辨率土地利用/覆盖变化方面有很好的适应性,对土地利用/覆盖变化的复杂性研究和相关部门对土地布局、规划方面具有一定的参考价值。模拟结果表明:到2030年湿地、人工用地、林地将增加,耕地和其它用地减少,草地在不同的情景下均有稍微的增加,耕地和人工用地是变化最大的两种类型,随着时间的推移耕地和林地面积不断接近甚至持平,研究区西部及西南部变化比较明显。     

湖北省道路网络中心性与土地利用景观格局关系分析

深入理解道路网络与土地利用之间的关系有助于开展可持续的土地利用与道路网络规划。引入多中心性评价模型,对临近中心性、中介中心性、直线中心性3个指标,运用UNA对湖北省道路网络中心性进行测度;选取景观百分比,香农多样性指数,平均斑块大小,平均形状指数4个景观格局指数计算土地利用景观格局特征,并通过斯皮尔曼相关方法对两者之间的关系进行探讨。结果表明:(1)湖北省道路网络中心性格局和空间特征各异,整体上东高西低,临近中心性呈现条带状分布,中介中心性呈孔隙状分布,直线中心性呈片状分布;(2)景观层面上,土地利用景观破碎化和多样化对直线中心性最为敏感,而临近中心性与中介中心性与景观格局指数关系相对复杂;(3)在类型层面上,道路网络中心性与各类土地利用景观格局相关性各异,其中高中心性区域对林地表现为鲜明的排斥和破碎化效应,而对建设用地表现为强烈的吸引和空间集聚现象。该研究以道路网络中心性视角探讨道路网络与土地利用景观格局之间的关系,为区域空间形态和构成及其相关影响因素提供了新的视角。     

青藏高原东缘典型流域生态系统#br# 服务的地形梯度效应#br# ——以岷江上游为例

山地生态系统受地形因素影响在垂向上呈现出明显的空间分异特征，厘清山地生态系统服务的空间分异特征是区域土地利用和生态系统管理的基础。以青藏高原东缘典型流域岷江上游为研究区，将2000、2005、2010年土地利用数据及DEM数据作为数据源，运用地形位指数、相对变化率和敏感性系数，研究土地利用变化下的生态系统服务价值的地形梯度效应。结果表明：（1）岷江上游土地利用类型以林地和草地为主，约占总面积的60%和30%；2000～2010年，1~4级地形位上除未利用地外的其他土地利用类型分布指数变化较为明显，林地和耕地不断降低，草地、水域和建设用地不断升高。（2 ）研究期内岷江上游生态系统服务价值总量和各类型生态系统服务的价值随地形位的升高均呈倒V形变化；2000～2010年，研究区1~12级地形位上生态系统服务价值呈增加趋势，13~20级地形位上呈减小 趋势。（3）2000～2010年，各地形位上生态系统服务价值变化趋势与研究区一致；除1级地形位上生态系统服务价值变化幅度略高于研究区外，2~20级地形位上的变化幅度与研究区基本一致。（4）研究 区各土地利用类型的单位面积生态系统服务价值敏感性系数均小于1，单位面积生态系统服务价值的变化缺乏弹性，研究结果可信；2000～2010年各地形位上水域、草地和荒漠敏感性系数不断上升，林地 和耕地敏感性系数不断下降。通过对土地利用变化驱动下的生态系统服务价值的地形梯度效应进行定量测度，明晰了生态系统服务价值随地形梯度变化所呈现的空间分异规律及其变化特征，为保护区域 生态系统，合理利用土地资源提供理论依据。 关键词： 土地利用；生态系统服务；地形位指数；地形梯度；岷江上游；青藏高原东缘     

典型流域土地利用/覆被变化及对水质的影响--以太湖上游浙江西苕溪流域为例

利用1985、1995和20D0年的TM数据及水质资料，运用GIS和水质指数法研究西苔溪流域的土地利用／覆被变化及其水环境效应。结果表明：流域内耕地不断减少，建设用地持续扩大，林地前期减少后期缓慢增加；林地和耕地是流域内的主要土地利用类型，二者面积之和占流域面积的比例在三个时段均在92％以上；空间集中性及斑块碎化是土地利用空间格局变化的主要表现，建设用地斑块数量增多且斑块面积明显增大，饼地面积减少但斑块数量增多。研究时段内流域水质在时间上呈逐步恶化趋势，在空间上则表现为自上游至下游逐渐下降，其中，1996-2000年，研究河段内水质指数下降幅度达30％左右；只治理点污染源仅使水质指数增加6．5％左右，表明影响水质的主要因素是土地利用变化导致的面源污染。     

基于Google Earth Engine的三峡库区土地利用与陆表参数变化研究

土地利用/覆盖变化(Land Use and Land Cover Change, LUCC)对全球有着重要影响,其已对植被覆盖、地表温度(Land Surface Temperature, LST)、反照率以及其它陆表参数产生显著影响。三峡工程自建设以来,库区的土地利用变化逐渐受到外界关注。利用欧空局300 m的土地覆盖分类数据分析三峡库区2000～2015年的土地利用变化;依托先进的Google Earth Engine(GEE)平台,获取MODIS(Moderate Resolution Imaging Spectroradiometer, MODIS)NDVI(Normalized Difference Vegetation Index, NDVI)、LST和反照率数据,并分析三者的时空变化趋势;此外,探究季节性归一化植被指数(Seasonally Integrated Normalized Difference Vegetation Index, SINDVI)与LST和反照率的关系;并分析土地利用变化对SINDVI、LST和反照率的影响。结果表明:2000～2015年,三峡库区土地利用变化显著,耕地、草地、灌木地分别减少2.4%,0.05%和0.62%;林地、水域和人造地表分别增加1.98%,0.04%和1.06%。研究期间SINDVI增加2.89,LST下降0.224℃,反照率减少0.002。总体来看,三峡库区SINDVI的空间分布格局与LST和反照率的相反,且库区大部分区域SINDVI与LST和反照率呈负相关。另外,不同土地类型对SINDVI、LST和反照率影响不同。该文系统地研究了LUCC与上述关键陆表参数的定量关系,可为更好地管理该地区自然环境和土地资源提供科学的依据。     

重庆市2000~2015年土地利用变化时空特征分析

研究区域土地利用变化及其时空特征，可以为将来的区域土地利用规划和管理提供基础。基于2000年、2005年、2010年和2015年4期土地利用遥感影像解译数据，结合GIS空间分析方法，从土地利用变化速度、转移方向、利用程度3个方面定量分析了重庆市2000~2015年土地利用变化的时空特征。结果表明：（1）研究期内，耕地、草地和未利用土地持续减少，且耕地减少速度呈增大趋势，主要减少区域分布在主城及周边区县；林地、水域和城乡建设用地面积增加。（2）区县之间各类土地利用变化的相对速率差异较大，其中草地的相对变化率相差最大，其次为水域、耕地和林地。耕地变化最大的区域主要集中在主城区，城乡建设用地在各区县均有较大变化；水域发生较大变化的区县均与大型水利工程的修建有关。（3）重庆市在2000~2005年土地利用变化最剧烈，随后朝着越来越稳定的方向发展；区县间土地利用变化剧烈程度差异明显，但这种差异朝着缩小的方向发展。（4）渝东北、东南区域耕地、林地、草地之间转换活跃，但活跃度随时间后移递减；耕地一直是其他地类最主要的转入来源之一，城乡建设用地越来越成为其他地类的主要转出方向。（5）重庆市土地利用水平总体上处于发展期，土地利用程度的区域分布格局基本上保持不变，但差异明显，越往东北、东南区域，土地利用程度越低；全市土地利用程度变化量的分布格局呈现为以渝中区为核心从内到外依次为“弱变化——剧烈变化——较强变化——较弱变化”的圈层扩展形态。     

An integrative approach to modeling land-use changes: multiple facets of agriculture in the Upper Yangtze basin

Land change science has emerged as a fundamental component of global environmental change and sustainability research. Still, much remains to be learned before scientists can fully assess future roles of land-use/cover changes (LUCC) in the functioning of the Earth system and identifying conditions for sustainable land use. The objective of this paper is to gain a better understanding of the complex interactions of human and natural drivers underlying LUCC. We do so by developing and estimating a novel structural model of land use and using spatially explicit longitudinal observations from the Upper Yangtze basin of China. Our analysis focuses on the multiple dimensions of agriculture—not only cropland use itself, but also grain production, soil erosion, and related technical change—and our data cover 31 counties over four time periods from 1975 to 2000. Our results show that technical change plays an important role in supplying food on a limited cropland; limiting cropland expansion in turn reduces soil erosion, which then benefits grain production in the longer term. It is also found that policies and institutions have significant impacts on land use and the status of soil erosion. Together, these results carry some great implications to sustainable land use and ecosystem management.     

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．     

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。