Projecting land use changes in the Neotropics: The geography of pasture expansion into forest

In tropical Latin America, pasture land for extensive grazing continues to expand, mostly at the expense of forest cover. Until now, scientists and policy makers tackling this issue had no geographically exhaustive information at the continental level about the spatial dynamics of this process. On the basis of a land use change-modeling framework we made a projection of potential land use changes for the year 2010.The chosen modeling framework incorporates a number of essential aspects of the complexity of land use change, such as the interrelation of spatial and temporal dynamics, land use history and scale dependence. The model was provided with up-to-date, continent wide, detailed information on present land use and its location factors, selected on the basis of literature. Model inputs were established in collaboration with experts from the region.Significant statistical relations were obtained that describe land use patterns in sub-regions, giving insights into the deforestation process and its location factors. Combined with decision rules and quantitative estimates of land use change, “hot spots” of forest to pasture and crop land conversion were projected. The results envisage a predominant replacement of forest by pasture. Substantially different trends among countries are predicted, both concerning the spatial patterns of deforestation and the substitution trends between land uses. The hot spot maps also show sensitive biological areas that may be at risk.The resulting continent wide map of projected change shall help to target policy attention and measures. It also provides a context to the numerous undergoing deforestation case studies. Finally, it is proposed that the study's results be considered in the priority setting of future research on the causes of deforestation.     

江淮地区强降水分型及其环流演变

使用新建的强降水历史个例数据集、1981-2016年我国逐日降水量观测资料、2016年T639与ECMWF模式1~10 d的逐日降水量预报,采用经验正交函数展开（EOF）提炼出江淮地区强降水的典型模态,并运用场相似法对江淮地区强降水进行客观分型,分析强降水的环流演变;定量诊断型环流相似所得与实测环流和降水的对应关系。结果表明:江淮地区强降水可分为Q_Ⅰ,Q_Ⅱ和Q_Ⅲ 3种类型,其中,Q_Ⅰ型降水中心位于江淮中部,Q_Ⅱ型表现为降水北多南少,Q_Ⅲ型表现为降水中间少南北多的分布。强降水对应的前期至当日,各型降水对应在亚洲的中高纬度地区均有显著的环流异常,且环流演变存在明显不同;但各类型降水对应的系统移动速度缓慢,且到强降水发生日江淮地区处于西太平洋副热带高压西北侧低值系统的控制,有利于该地区强降水的发生。按环流相似依不同时效得到的强降水发生日环流与实际环流存在很好的相关。独立试验中,该文方法对25 mm降水的TS评分在各时效均高于模式预报,50 mm降水的TS评分在3 d以上时效的评分也均高于模式预报。     

长江三角洲地区水和热通量的时空变化特征及影响因子

文中利用改进的K B模式和牛顿扩散方法及 196 1年以来的长江三角洲 (2 8～ 33°N ,118～ 12 3°E)地区的 4 8个测站的常规气象资料 ,估计了该地区近 4 0a来的蒸散量和感热通量。结合该地区的气温、太阳辐射等气候资料和 196 0年以来该区域土地资源利用变化等有关信息对该地区的潜热通量和感热通量的时 空间变化特征及其可能成因进行了综合分析。结果认为该地区自 2 0世纪 70年代开始平均蒸散量有逐渐减小的趋势 ,与 1980年相比 ,1998年区域年平均蒸散量减小了 2 4mm。区域平均感热通量与蒸散量相比在此期间变化并不明显。通过对该地区的云量、太阳辐射及土地利用变化资料分析认为 ,造成该地区平均蒸散量减少趋势的的原因之一是用于蒸发的能量即太阳辐射的减少 ,而造成太阳辐射减少的可能原因为云量及大气透明度的变化所至 ;原因之二是该地区地表覆盖条件的改变。近 2 0a来 ,该地区的水田、旱地及水域面积占总面积的比率分别减少 1.35 3% ,4 .4 4 2 %和2 .5 97% ,而城镇建设、工矿及其它建设用地面积则增加 3.345 %。耕地及水面的减小和城镇及建设用地面积的增加从整体上使区域平均蒸发量减少。     

沙尘暴天气的归类判别分析预报模式

在大量分析了历史上 4 0年发生在内蒙古中西部地区的 37场沙尘暴天气过程的基础上 ,总结归纳了其大气环流特征 ,将他们划分成 4个环流类型。参考SaatyT .L .,提出的综合选优的方法[1] ,建立判别矩阵 ,然后计算归类判别预报 ,根据判别函数值判断实时待判样本的归属。参照归属类历史沙尘暴的天气形势和实况出现的范围以及强度作出沙尘暴天气预报 ,并设计了一个沙尘暴天气的归类判别分析预报模式。该模式已较成功地应用于 2 0 0 0年春季内蒙古地区的沙尘暴天气预报业务中 ,取得了较好的预报效果。实践证明 ,它是一个客观化、定量化和计算自动化的实用的预报模式 ,是我们目前作沙尘暴预报的重要技术手段之一。     

A Method for Estimating the Cost of CO2 Mitigation through Afforestation

The Kyoto Protocol allows Annex I countries to use afforestation (theconversion of non-forest landto forest) to meet emissions reduction targets. We present a new method forestimating the cost of CO₂mitigation through afforestation based on econometric models of land use. Landuse models are developed from dataon observed land allocation decisions and quantify the relationship betweenthe share of land in forest and the netreturns to forestry, among other land use determinants. The econometricapproach measures the actual responsesby landowners to observed changes in net returns, in contrast to earlierstudies in which landowner responses aredictated by the researcher. Models are estimated for Maine, South Carolina,and Wisconsin. The estimated modelsare used to simulate subsidies for afforestation, which imply increases inforest area and net reductions inatmospheric CO₂ concentrations. Average cost measures – totalsubsidies divided by total carbon sequestered –are derived for afforestation programs with and without timber harvesting. Theuse of econometric land use modelsin integrated assessments of climate change is explored. We model the effectson land use patterns and the costsof CO₂ mitigation of changes in the net returns to agricultureinduced by climate change.     

Land use change under conditions of high population pressure: the case of Java

A long history of increases in population pressure in Java has caused agricultural land use to expand and intensify. More recent land use changes caused the conversion of prime agricultural land into residential and industrial area. Results of a dynamic, regional-scale, land use change model are presented, defining the spatial distribution of these land use changes. The model is based on multi-scale modelling of the relations between land use and socio-economic and biophysical determinants. Historical validation showed that the model can adequately simulate the pattern of land use change. Future patterns of land use change between 1994 and 2010 are simulated assuming further urbanization. The results suggest that most intensive land use changes will occur in Java's lowland areas.     

The land cover and carbon cycle consequences of large-scale utilizations of biomass as an energy source

The use of modern biomass for energy generation has been considered in many studies as a possible measure for reducing or stabilizing global carbon dioxide (CO₂) emissions. In this paper we assess the impacts of large-scale global utilization of biomass on regional and grid scale land cover, greenhouse gas emissions, and carbon cycle. We have implemented in the global environmental change model IMAGE the LESS biomass intensive scenario, which was developed for the Second Assessment Report of IPCC. This scenario illustrates the potential for reducing energy related emission by different sets of fuel mixes and a higher energy efficiency. Our analysis especially covers different consequences involved with such modern biomass scenarios. We emphasize influences of CO₂ concentrations and climate change on biomass crop yield, land use, competition between food and biomass crops, and the different interregional trade patterns for modern biomass based energy. Our simulations show that the original LESS scenario is rather optimistic on the land requirements for large-scale biomass plantations. Our simulations show that 797 Mha is required while the original LESS scenario is based on 550 Mha. Such expansion of agricultural land will influence deforestation patterns and have significant consequenses for environmental issues, such as biodiversity. Altering modern biomass requirements and the locations where they are grown in the scenario shows that the outcome is sensitive for regional emissions and feedbacks in the C cycle and that competition between food and modern biomass can be significant. We conclude that the cultivation of large quantities of modern biomass is feasible, but that its effectiveness to reduce emissions of greenhouse gases has to be evaluated in combination with many other environmental land use and socio-economic factors.     

Human appropriation of land for food: The role of diet

Human appropriation of land for food production has fundamentally altered the Earth system, with impacts on water, soil, air quality, and the climate system. Changes in population, dietary preferences, technology and crop productivity have all played important roles in shaping today’s land use. In this paper, we explore how past and present developments in diets impact on global agricultural land use. We introduce an index for the Human Appropriation of Land for Food (HALF), and use it to isolate the effects of diets on agricultural land areas, including the potential consequences of shifts in consumer food preferences. We find that if the global population adopted consumption patterns equivalent to particular current national per capita rates, agricultural land use area requirements could vary over a 14-fold range. Within these variations, the types of food commodities consumed are more important than the quantity of per-capita consumption in determining the agricultural land requirement, largely due to the impact of animal products and in particular ruminant species. Exploration of the average diets in the USA and India (which lie towards but not at global consumption extremes) provides a framework for understanding land use impacts arising from different food consumption habits. Hypothetically, if the world were to adopt the average Indian diet, 55% less agricultural land would be needed to satisfy demand, while global consumption of the average USA diet would necessitate 178% more land. Waste and over-eating are also shown to be important. The area associated with food waste, including over-consumption, given global adoption of the consumption patterns of the average person in the USA, was found to be twice that required for all food production given an average Indian per capita consumption. Therefore, measures to influence future diets and reduce food waste could substantially contribute towards global food security, as well as providing climate change mitigation options.     

西北干旱区荒漠水分循环特征及其模拟

利用"中国西北干旱区陆—气相互作用实验"观测的资料,分析了大气湿度、土壤含水量、与土壤含水量相关的陆面参数及其他陆面参数特征。为了验证新的陆面参数及参数化公式,将新陆面参数与参数化公式输入陆面模式进行模拟,将模拟值与观测值进行了比较。结果表明输入新参数及参数化公式的模拟效果更好。     

Responses of urban heat island in Atlanta to different land-use scenarios

The urban heat island (UHI) effect changes heat and water cycles in urban areas, and has been accused of elevating energy consumption, deteriorating living environment, and increasing mortality rates. Understanding various UHI effects necessitates a systematic modeling approach. A major problem in UHI simulations is that urban areas were either considered to have only one category of land use/cover or outdated in land use/cover patterns due to the lack of high resolution data. Therefore, this study aims at integrating up-to-date remotely sensed land use/cover data with the Weather Research and Forecasting (WRF/UCM)/Urban Canopy Model modeling systems to simulate surface temperature patterns in Atlanta, Georgia. In addition, three land-use scenarios, i.e., spontaneous scenario (SS), concentrated scenario (CS), and local policy scenario (LPS), were designed and incorporated into the modeling. Five numerical experiments were conducted by using the Weather Research and Forecasting (WRF) model to explore the impact of urbanization-induced land-cover changes on temperature patterns. Land use and land-cover patterns under all three scenarios suggested that urban growth would continue through in-filling development and outward expansion. Compared to temperature simulations in 2011, temperature maps corresponding to the three urban growth scenarios showed warmer and cooler temperature patterns outside and inside the urban core, respectively. Analysis of the mean diurnal temperature cycle suggested that the highest temperature difference of 3.9 K was observed between 2011 and the LPS, and occurred around 22:00 local time. Overall, the simulations showed different UHI effects respond to the land-use scenarios in the summer. It is recommended for urban managers and policy makers to reflect on the potential impacts of alternative urban growth policies on thermal environment.     

The relative influence of climate and housing development on current and projected future fire patterns and structure loss across three California landscapes

Climate and land use patterns are expected to change dramatically in the coming century, raising concern about their effects on wildfire patterns and subsequent impacts to human communities. The relative influence of climate versus land use on fires and their impacts, however, remains unclear, particularly given the substantial geographical variability in fire-prone places like California. We developed a modeling framework to compare the importance of climatic and human variables for explaining fire patterns and structure loss for three diverse California landscapes, then projected future large fire and structure loss probability under two different climate (hot-dry or warm-wet) and two different land use (rural or urban residential growth) scenarios. The relative importance of climate and housing pattern varied across regions and according to fire size or whether the model was for large fires or structure loss. The differing strengths of these relationships, in addition to differences in the nature and magnitude of projected climate or land use change, dictated the extent to which large fires or structure loss were projected to change in the future. Despite this variability, housing and human infrastructure were consistently more responsible for explaining fire ignitions and structure loss probability, whereas climate, topography, and fuel variables were more important for explaining large fire patterns. For all study areas, most structure loss occurred in areas with low housing density (from 0.08 to 2.01 units/ha), and expansion of rural residential land use increased structure loss probability in the future. Regardless of future climate scenario, large fire probability was only projected to increase in the northern and interior parts of the state, whereas climate change had no projected impact on fire probability in southern California. Given the variation in fire-climate relationships and land use effects, policy and management decision-making should be customized for specific geographical regions.     

土地利用城市化对珠三角炎热天气的影响.

土地利用类型的变化对MM5模拟结果的准确性有着重要的影响。不同的土地利用类型,有着不同的地表粗糙度,反照率,热容量,有效湿度等,从而产生不同的模拟地面热通量及地面水汽通量,并通过垂直方向的湍流输送,影响到高空气象场的模拟结果。利用2001年卫星遥感土地类型等数据,对MM5系统旧的24类全球土地利用数据在珠三角区域进行了更新;通过把珠三角地区的土地利用设为常绿阔叶林和城市两种不同类型的敏感性模拟测试,可以看到土地利用的变化,对温度、风场等气象场的模拟结果影响较大;通过1993年和2001年土地利用情况下的模拟气象场及与观测数据的对比分析可以知道,采用新的土地利用类型可以较好地改进MM5气象场模拟结果的准确性,土地利用的城市化趋势会造成城市密集地区地表温度升高,水汽混合率降低。     

基于Landsat TM/ETM＋数据的北京城市热岛季节特征研究

利用1988—2006年20景LandsatTM和ETM＋数据分析了北京市城市热岛的季节变化特征。通过反演地表温度,建立统一的城市和农村区域,计算了城市热岛强度,并采用多项式拟合获取了城市热岛强度的季节变化曲线;同时,分析了热岛强度季节特征与气候因子的关系。另外利用4景2005—2006年不同季节Landsat TM影像,分析了不同季节城市热岛的空间变化特征,并选择穿越北京城区的两条不同方向剖线（SE-NW和SW-NE）,分析了沿剖线方向城市热岛与地表类型的关系。结果显示,北京城市热岛具有明显的季节变化特征,与总云量的季节变化关系显著。最大热岛强度出现在夏季,呈现片状发散和零星热岛并存的空间分布特征。冬季为冷岛特征,其空间分布与夏季热岛一致。春秋两季热岛强度最小,但春季热岛空间差异较大。在相同季节,城市热岛强度和空间尺度在不同剖线方向具有明显的差异,这与不同地类的空间分布有关。     

Promise and reality of market-based environmental policy in China: Empirical analyses of the ecological restoration program on the Qinghai-Tibetan Plateau

Environmental conservation programs in China have increasingly emphasized integration of market-based logic into regulatory programs. But the realization of market logic and the effectiveness of such efforts are widely questioned by scientists and policy analysts. We empirically analyze the design, implementation, and outcomes of the ecological restoration program in the Three-Rivers Headwater Region in China, a large-scale conservation scheme aimed at restoring degraded grasslands and improving local livelihoods. Results indicate that the market mechanisms emphasized in the design of the policy were not realized in practice due to inadequate use of scientific measurements, lack of accountability, and poor monitoring and enforcement. Moreover, because enrollment was not voluntary, as is generally expected in market-based programs, there were negative impacts on herders. A household survey (n = 202) of local herders shows that if conservation incentives were properly designed and implemented, 67% would voluntarily participate in the program. Variance recorded in ecological and socioeconomic conditions points to opportunities to use market-based policy instruments to integrate local information into decision making regarding targeting of land conservation and land retirement. The potential of market-based environmental policies can be expanded through commitments to scientific measurement, voluntary participation, and outcome-based payments.     

Abnormal weather events in 2009, increased precipitation and disastrous impacts in the Philippines

The Philippines has recently experienced distinct changes in the weather patterns with disastrous results. These changes which were distinctly felt in 2009 included: 1. too much precipitation throughout the year; 2. some areas received a lot of rain while other parts of the country went through dry spell and drought conditions; and 3. abnormalities and variance in weather patterns (e.g. multiple entry of a tropical cyclone during an El Niño event; longer duration of tropical cyclone; deviations from the normal tropical cyclone path). The country, with its disaster risk management program in place, has managed to bring down the cost of damage and number of casualties due to weather-related disasters. However, in some instances, disaster risk response was made difficult due to other factors (e.g. degraded ecosystem, ill-managed land use and risk denial by people and communities). In general though, the resiliency and ability to recover by the people devastated by these disasters and the availability of community-based support systems provided the best means of coping with these catastrophic events. This is important as climate change is projected to bring more variations in the country’s weather and climate patterns which, as of now, are already adversely affecting the people.     

Integrating global and regional analyses of the effects of climate change: A case study of land use in England and Wales

The purpose of this paper is to exemplify a means by which an integrated assessment can be made of global and regional effects on land use of climate change. This is achieved by use of data on the effects of climate change on world food prices as inputs to a regional land use allocation model.Data on world prices are drawn from a recent global study of climate change and crop yields. In a case study of England and Wales a land allocation model is used to infer changes of land use that are the product of the integrated effect of climate-induced global price changes and climate-related changes of yield in England and Wales. This combination of changed prices and yield potential is used to calculate the land use providing the highest returns for each of 155,235 1 km² cells of land in England and Wales for a future assumed for the year 2060 (without climate change) and then for that same environment with climate change. The difference between these two is then treated as an estimated effect resulting from climate change.     

Comparative Studies In The Local Circulations Induced By Land-Use And By Topography

A two-dimensional numerical model witha simplified land-use paramaterizationis used to investigate the effects of land usetopography on local circulationsystems. A criterion is presented indicating therelative importance of land use onlocal circulations.Land-use contrast in the numerical model is parameterized by moisture availability and roughness length. Numerical experiments were carried out under various atmospheric stabilities with various dimensions for the mountains.Numerical results show the following: (1) Anabatic winds prevail in high mountains,while the land–land breeze is stronger when the horizontal contrast of the heat fluxfrom each land surface is large. (2) In the early morning, anabatic winds tend to prevailover land–land breezes, but the land–land breeze tends to prevail in the later afternoon.(3) While atmospheric stability has a large influence on the mesoscale circulation, thehorizontal scale of the mountain is not as important for the intensity of the mesoscalecirculation. (4) In strong stable conditions or weak insolation, the anabatic wind tendsto be more active than the land–land breeze; namely, the heat flux from inhomogeneousland use becomes a less important factor for the generation of a mesoscale disturbancethan the orographic forcing in the case of strong atmospheric stability. (5) The predominantmesoscale circulation is predicted by a criterion based upon the horizontal adjustmenttheory of the mixed layer. The criterion proposed in this study is based on the mountainheight, the ratio of the heat flux from the different land use patterns, the atmospheric staticstability, and the time-integrated heat flux. The criterion gives results that generally agreewith the numerical results.     

Mapping global land system archetypes

Land use is a key driver of global environmental change. Unless major shifts in consumptive behaviours occur, land-based production will have to increase drastically to meet future demands for food and other commodities. One approach to better understand the drivers and impacts of agricultural intensification is the identification of global, archetypical patterns of land systems. Current approaches focus on broad-scale representations of dominant land cover with limited consideration of land-use intensity. In this study, we derived a new global representation of land systems based on more than 30 high-resolution datasets on land-use intensity, environmental conditions and socioeconomic indicators. Using a self-organizing map algorithm, we identified and mapped twelve archetypes of land systems for the year 2005. Our analysis reveals similarities in land systems across the globe but the diverse pattern at sub-national scales implies that there are no ‘one-size-fits-all’ solutions to sustainable land management. Our results help to identify generic patterns of land pressures and environmental threats and provide means to target regionalized strategies to cope with the challenges of global change. Mapping global archetypes of land systems represents a first step towards better understanding the global patterns of human–environment interactions and the environmental and social outcomes of land system dynamics.     

The integrated socio-perceptual approach: Using ecological mental maps and future imaginaries to understand land use decisions

Rural places are important centers of environmental and social transformation. Landholders are not only affected by socio-environmental changes, but they are influencing futures related to climate change, food security, freshwater, biodiversity, and social and economic development. Much environmental land use work understands individual landholders as rational actors, portrayed through the economic lens of “producer.” These approaches generally focus on present capacities and limitations as the principal factors contributing to land use, and the individual farm as the reference unit for decisions. Our research takes steps to expand conceptualizations of rural landholders as active and knowledgeable in envisioning, managing, and shaping environmental futures. We design and test a new approach using ecological mental maps and future imaginaries to understand land use practices through a case study in the cocoa-producing and Atlantic Forest region of Southern Bahia, Brazil. The integrated socio-perceptual (ISP) approach combines qualitative and quantitative methodologies to honor the depth of landholders’ experiences and perspectives and to allow broader regional relationships and insights to emerge. We demonstrate that the ISP approach—through 49 surveys—has the capacity to capture variation and identify patterns in ecological mental maps and future imaginaries in a population, approximate the relevant spatial scales underlying these factors, and identify relationships between these and land uses. In this context, the types of narratives landholders hold about the region’s future are associated with current forest land use on their properties. We discuss potential applications of the ISP approach for land use study and practice.     

Economic and ecosystem costs and benefits of alternative land use and management scenarios in the Lake Rotorua,New Zealand,catchment

A significant challenge in resource management is addressed: the perceived trade-off between economic growth and ecosystem restoration and conservation. Traditional approaches to management regard restoration as a potential cost to economic productivity. In this study we show that by considering a broader range of economic values, including ecosystem services values, an argument can be made that restoration of lake ecosystems also leads to favourable economic outcomes when commonly disregarded values are considered. Our case study analyses the ecological outcomes of different catchment mitigation and land use scenarios in terms of water quality results in a lake, assessing changes in land use values based on opportunity costs, and ecosystem services values. We show that when considering the value of ecosystem services, intensive agricultural land use is not necessarily the most economically valuable form of land use within a lake catchment. Indeed, a shift towards alternative land uses within a catchment can lead to both ongoing economic benefits and improvements in water quality. In this context, land-use change offers an option for water quality improvement that minimises lake and land mitigation costs, while adding value to catchment land use. An argument is made supporting land use change towards indigenous forest types, which can sustain alternative sources of income such as a range of recreational values, while supporting important ecosystem functions for the region.