Integrating socio‐economic and biophysical models: revision of a land‐use allocation model

Integration of large‐area, economically driven macro‐models and small‐area, biophysically based models in the Canadian agricultural sector was described recently in the development of a land‐use allocation model (LUAM). We have since developed and integrated an improved methodology for allocating crop area changes generated for large areas by the Canadian Regional Agricultural Model (CRAM) to much smaller Soil Landscapes of Canada (SLC) polygons. Validation of outputs showed considerable improvement. The new coefficients of determination (R²) between simulated and actual data, with previous values in brackets, were 0.69 for fodder corn (0.54), 0.88 for wheat (0.62), 0.77 for hay (0.26), 0.54 for alfalfa (not previously reported), 0.88 for soya bean (0.26) and 0.86 for grain corn (0.22). The best result was obtained for soya bean, with a normalized root mean square error (NRMSE) of 0.31%, and the poorest for alfalfa, with NRMSE = 17.34%.     

Integration of biophysical and socio‐economic factors to assess soil erosion hazard in the Upper Kaligarang Watershed,Indonesia

Soil erosion is one form of land degradation, which is caused by the interacting effects of numerous factors such as biophysical characteristics and socio‐economic condition of a particular watershed. Previous erosion studies focused on the use of soil erosion models (e.g. USLE, EUROSEM, SLEMSA etc.), which have been developed under local conditions (e.g. United States, Europe, Africa, etc) and mostly use only biophysical factors as inputs to the models. In this study, a methodology that integrates both biophysical and socio‐economic aspects into a framework for soil erosion hazard assessment using principal component analysis (PCA) is described. The analysis is done at the land unit level. With the particular conditions of the study area that is characterized by Inceptisols and Alfisols soil types, nine different land uses with mixed vegetation and forest area dominant in the steep slope, high annual rainfall (>2500 mm), high population with mostly low income and low education, were considered. These were used in formulating a soil erosion hazard index (EHI) equation which relates a number of key factors consisting of biophysical and socio‐economic variables, namely soil texture, slope steepness, land cover, soil conservation practices, income and farmers' knowledge. Weighting and scoring of these key factors were used to develop the EHI equation and to calculate an index value of erosion hazard for every land unit. Results indicate that more than 60% of the area has erosion hazard ranging from moderate to very severe, and most of the land units with high erosion hazard were found at the mountain areas. It was also found that erosion hazard was severe in areas with high silt content, followed by high rainfall and steep slope, low crop cover without any soil conservation practices coupled with lack of awareness on soil erosion and low income. The key factors identified and level of erosion hazard obtained can be used to formulate conservation measures in critical areas which are prone to soil erosion. Copyright © 2007 John Wiley & Sons, Ltd.     

Integrating socio‐economic and biophysical assessments using a land use allocation model

This work is devoted to bridging the gap between large‐area, economically driven macromodels such as the Canadian Regional Agriculture Model (CRAM) and small‐area biophysically based process models used in environmental assessments through the development of a Land Use Allocation Model (LUAM). LUAM is designed to enable environmental assessments of economic scenarios to be conducted by allocating crop area changes predicted for large areas by CRAM to much smaller Soil Landscapes of Canada (SLC) polygons through an optimization method based on land capability, relative crop productivity and current land use. To develop the procedures, we used linear programming to optimize crop production for large areas under current commodity prices and land productivity ratings and then allocated the results to much smaller soil‐landscape polygons based on land capability. To assess the validity of our prototype LUAM, we compared the predicted crop areas with actual crop data from the Census of Agriculture using the method of cumulative residuals (MCR). We concluded that this version of the LUAM model can predict the location of land use to some extent, but requires further refinement. The potential for further development of LUAM using the Land Suitability Rating System (LSRS) is discussed.     

New frontiers of land and water commodification: socio‐environmental controversies of large‐scale land acquisitions

A growing number of regions in the developing world are targeted by transnational investors who are acquiring large amounts of land and natural resources. Driven by the increasing global demand for agricultural products, such investments are often considered an opportunity for economic development in the target country. However, there are concerns about the social and environmental impacts on local communities. In this brief review, we discuss some key socio‐environmental controversies surrounding large‐scale land acquisitions (LSLAs). LSLAs often target common property systems and lead to privatization and commodification of land through long‐term land concessions. There is a debate between supporters of foreign land investments as a means to attract modern agricultural technology that would decrease the yield gap in underperforming agricultural land and those who question such a development model because it is seldom coupled with policy instruments that would ensure that the benefits improve food security in local populations. Large‐scale land investments displace a variety of systems of production ranging from small‐scale farming to (arguably) “unused” land such as forests and savannas on which local communities often depend. Moreover, LSLAs entail an appropriation of water resources that may negatively impact local farmers or downstream human and natural systems. In most cases, investors keep the land fallow but, when they put it under productive use, they typically change land cover and land use to start intensified commercial farming, often for nonfood crops. Copyright © 2017 John Wiley & Sons, Ltd.     

Land use and soil erosion in the upper reaches of the Yangtze River: some socio‐economic considerations on China's Grain‐for‐Green Programme

Soil erosion in the upper reaches of the Yangtze River in China is a major concern and the Central Government has initiated the Grain‐for‐Green Programme to convert farmland to forests and grassland to improve the environment. This paper analyses the relationship between land use and soil erosion in Zhongjiang, a typical agricultural county of Sichuan Province located in areas with severe soil erosion in the upper reaches of the Yangtze River. In our analysis, we use the ArcGIS spatial analysis module with detailed land‐use data as well as data on slope conditions and soil erosion. Our research shows that the most serious soil erosion is occurring on agricultural land with a slope of 10∼25 degrees. Both farmland and permanent crops are affected by soil erosion, with almost the same percentage of soil erosion for corresponding slope conditions. Farmland with soil erosion accounts for 86·2 per cent of the total eroded agricultural land. In the farmland with soil erosion, 22·5 per cent have a slope of < 5 degrees, 20·3 per cent have a slope of 5∼10 degrees, and 57·1 per cent have a slope of > 10 degrees. On gentle slopes with less than 5 degrees inclination, some 6 per cent of the farmland had strong (5000∼8000 t km⁻² y⁻¹) or very strong (8000∼15000 t km⁻² y⁻¹) erosion. However, on steep slopes of more than 25 degrees, strong or very strong erosion was reported for more than 42 per cent of the farmland. These numbers explain why the task of soil and water conservation should be focused on the prevention of soil erosion on farmland with steep or very steep slopes. A Feasibility Index is developed and integrated socio‐economic assessment on the feasibility of improving sloping farmland in 56 townships and towns is carried out. Finally, to ensure the success of the Grain‐for‐Green Programme, countermeasures to improve sloping farmland and control soil erosion are proposed according to the values of the Feasibility Index in the townships and towns. These include: (1) to terrace sloping farmland on a large scale and to convert farmland with a slope of over 25 degrees to forests or grassland; (2) to develop ecological agriculture combined with improving the sloping farmland and constructing prime farmland and to pay more attention to improving the technology for irrigation and cultivation techniques; and (3) to carry out soil conservation on steep‐sloping farmland using suggested techniques. In addition, improving ecosystems and the inhabited environment through yard and garden construction for households is also an effective way to prevent soil erosion. Copyright © 2006 John Wiley & Sons, Ltd.     

基于土地整理的耕地经济价值评定及其变化

耕地经济价值评定是土地整理重要技术工作之一,其评价结果是土地整理经济效益评价的重要依据。该文以莱芜市里辛土地整理项目为例,采用GIS技术、实地调查和室内分析相结合,探讨了基于土地整理的耕地经济价值评定指标体系、评价方法及整理前后价值变化。研究结果表明,研究区在土地整理前后,耕地经济价值的级别空间分布、面积和总价值都发生很大改变。整理前耕地主要是旱地,经济价值级别主要为二、三和四级地,占总耕地面积的87.20%,一级地很少;整理后耕地全部为菜地和水浇地,级别基本为一、二级地,占总耕地面积的99.88%。整理后的耕地经济总价值是整理前的1.286倍,土地整理经济效益显著。该研究方法对土地整理耕地经济价值评定有借鉴意义,评价结果可为莱芜市里辛土地整理绩效评价提供科学依据。     

The influence of land use and fallow period on the properties of two calcareous soils in the humid tropics of southern Mexico

Calcareous soils are common in the humid tropics of Mexico, but little is known about their productivity and resistance to changes in land use. The influence of land use and duration of fallow on physical and chemical properties were investigated in (a) a loamy Rendzina (at Site A) rich in organic matter and limited in depth by calcareous gravel, and (b) a deeper Calcaric Phaeozem (at Site B) with a more clayey texture throughout. Plots at different successional stages within farmers' shifting cultivation systems were selected on both soils: cropland/young fallow (zero years fallow length), shrub-fallow and tree-fallow at Site A, and cropland/young fallow and forest at Site B. Changes in soil properties suggested a process of recovery with fallow length, in which organic matter, total N and CEC increased with time. The increase in organic matter was remarkably large, on average 0.5–0.6% per year. The Rendzina contained more organic matter than the Calcaric Phaeozem, probably because of its greater carbonate content, which is presumed to protect organic matter against decomposition. The differences in soil properties were mostly greater over time than between treatments.     

Long‐term changes in the floristic composition and soil characteristics of reclaimed sodic land during eco‐restoration

The study was conducted under the “Uttar Pradesh Sodic Lands Reclamation Project” to examine changes that occurred in the reclaimed sodic land in two districts of Uttar Pradesh, India. The study focuses on long‐term seasonal changes in the floral diversity and soil characteristics of the reclaimed sodic land over a period of 10 y. The changes in the floristic composition, plant density, and soil characteristics (microbial biomass carbon [MBC], pH, exchangeable‐sodium percentage (ESP), and electrical conductivity) were compared among the different study plots after different years of sodic‐land reclamation. The study plots comprised reclaimed land with rice–wheat cultivation; semireclaimed land under rice cultivation only and nonreclaimed barren sodic land. There was a significant variation in the floristic composition of the three study plots. Dominance in the floristic composition was shifted from monocotyledonous weeds in the nonreclaimed sodic land to dicotyledonous weeds in the reclaimed land after 10 y of reclamation. Among the soil characteristics, the most remarkable changes were observed in soil MBC and ESP during the course of sodic‐land reclamation. Soil MBC increased up to 480% and ESP values decreased up to 79% in the reclaimed plots with reference to the nonreclaimed plots. The soil amelioration was more pronounced in the upper layer (0–30 cm) as compared to the lower layer (below 30 cm depth). A positive significant correlation was revealed between soil MBC and floristic composition of the reclaimed plots. These changes in floristic composition and soil characteristics could be used as good indicators of the eco‐restoration of the sodic lands. The present study provides useful insights in understanding the temporal progress of eco‐restoration in the reclaimed sodic lands.     

The nature, causes and implications of water erosion on arable land in Scotland

Abstract. Erosion was surveyed in Strath Earn, Scotland, following severe weather conditions during the first 18 days of January, 1993. A rapid field mapping system was devised to record the nature of erosion. A total of 208 fields was surveyed and 76 exhibited erosion. Most fields with erosional features were either ploughed or in autumn cereals. The most common form of erosion was ephemeral gullies along topographic hollows. This erosion was primarily associated with ploughed land whereas sheetwash and rill erosion occurred more on autumn sown land. Land use change and climatic variability, especially increasing rainfall over the last 20 years, account for the incidence of erosion. Individual erosion events rarely cause major problems for farmers, but the increasing frequency of erosion events raises important questions for sustainable land use in the arable areas of Scotland.     

A systems analysis of soil and forest degradation in a mid‐hill watershed of Nepal using a bio‐economic model

Forest degradation, manifested through decline in forest cover, and the resulting soil erosion and organic carbon losses, is a serious problem caused by a complex coupling of bio‐physical, socio‐economic and technological factors in the Himalayan watersheds. Greater understanding of the linkages between these factors requires a systems approach. We have proposed such an approach using a bio‐economic model to explore the system behaviour of forest degradation, soil erosion, and soil C losses in the forest areas. The outcome of the model simulation over a 20‐year period indicates that soil erosion and C loss rates may increase more than four‐fold by the year 2020 under the existing socio‐economic and biophysical regime (the base scenario). Reductions in the population growth rate, introduction of improved agricultural technology and increase in the prices of major agricultural crops can help slow down the rates of forest decline, soil erosion and C loss or even stabilize or reverse them. The results suggest that economic incentives may be highly effective in the reduction of soil loss, as well as C release to the atmosphere. Copyright © 2005 John Wiley & Sons, Ltd.     

Multi‐factorial causes of land‐use change: land‐use dynamics in the agropastoral village of Im Mial,northwestern Syria

Land‐use dynamics in drylands are complex processes. In the context of a typical agropastoral village in northwestern Syria Im Mial, the effects of demographic and social changes, reduced soil productivity, changes in agricultural technologies and historical events on land use and land productivity are examined. Decreasing yields, mainly the result of reduced fallow periods and low investments in the land, and the deterioration of the grazing resources are the two main signs of the loss of land productivity in the area. The growing population forces the villagers to practise continuous rainfed barley cultivation with no or only occasional fallow, and without any application of plant nutrients. Also, technological changes, from the use of donkey ploughs and hand harvesting to less labour‐intensive and time‐consuming cultivation practices with tractors and combine harvesters, and the increased importance of stubble in the livestock diet have contributed to the reduction of the fallow periods. The villagers attribute the yield decreases mainly to the low rainfall in the area. The high rainfall variability discourages the fallowing of fields because continuous cultivation maximizes the chances for good harvests in years with high rainfall. There is also an expansion of cultivation into the less fertile and sloping traditional grazing areas. Population growth, increased numbers of livestock and the expansion of cultivated land into grazing areas has also put pressure on the grazing resources of the village. The possession of livestock is seen as a sign of wealth and the villagers aim to have large flocks of animals. For them, livestock is also an important means for investment of cash earned from off‐farm work, which is the main source of income for most of the households in the village. There is a recent trend of increasing levels of crop‐livestock integration with less free grazing that produces higher return to the land users. This may also have a positive effect on the restoration and conservation of the degraded natural traditional grazing grounds. The stabilization and productive use of the land resources in this dry environment requires the combined and interdisciplinary effort from both the land‐users and the policy‐makers. Copyright © 2001 John Wiley & Sons, Ltd.     

中国耕地差异化休耕模式及技术措施探讨

耕地休耕模式是实行耕地休耕制度的重要组成部分,探索差异化的休耕模式对中国全面实施耕地休耕制度具有重要意义。该研究运用文献研究法、归纳总结法、系统分析法及案例分析法等,结合中国耕地休耕主要试点区实地调研资料及数据,总结、提炼差异化耕地休耕模式。结果表明：中国耕地休耕模式设计应充分考虑制度主体、制度客体及制度环境等因素的影响,从模式内涵、模式适用区域、典型案例区及主要休耕技术措施等进行设计。中国耕地差异化休耕模式主要有地下水漏斗区节水保水型休耕模式、土地污染区清洁去污型休耕模式、生态严重退化区生态修复型休耕模式、耕作过度集约化区耕地地力保护型休耕模式及耕地撂荒严重区的\     

土地整理的资源与经济效益评估方法

研究土地整理资源与经济效益定量评估方法,是分析土地整理经济社会效应的基础,也会对土地整理项目区域的选择和土地整治规划的编制提供指导作用。该文将土地整理的资源效益分为增产和增地效益,将经济效益分为直接经济效益和间接经济效益,采用理论分析与专家咨询相结合的方法,分别选取了评估指标,实现了指标评估的量化。同时选择北京市大兴区进行了实证研究,采用农户调查与统计年鉴数据分析相结合的方法,估算了大兴区土地整理的资源与经济效益。实证研究表明该文所建立的土地整理资源与经济效益的评估指标与方法具有科学性和可操作性,且评估结果说明大兴区土地整理的资源与经济效益数量相当可观。     

Climate‐strategic agriculture and the water‐soil‐waste nexus

Adoption of input‐responsive varieties enhanced food production during the second half of the 20th century. However, even bigger challenges lie ahead because of the growing societal demands. For example, the global population of 7.2 billion in 2013 is projected to reach 9.2 billion by 2050 and stabilize at 10 billion by 2100. The growing and increasingly affluent population, with preference towards more and more meat‐based diet, is likely to jeopardize the finite, fragile, and dwindling soil and water resources which are already under great stress in densely populated countries in Asia and elsewhere. Economic growth and increase in gross domestic product also lead to generation of waste or by‐products, along with contamination and eutrophication of water resources. International trade in food/feed products also involves transfer of virtual water, which is a serious issue when water‐scarce countries export virtual water to water‐endowed countries. The problem is confounded by the present and future climate change driven by the growing energy demands of the carbon civilization. Thus, adaptation to climate change represents both a threat and an opportunity for sustainable development. Adaptive strategies must be sustainable socially and environmentally and advance the Millennium Development Goals, while buffering agroecosystems against extreme climate events (e.g., pedologic, agronomic, and ecologic drought). Thus, recognizing and addressing the water‐soil‐waste nexus is important to achieving climate‐strategic agriculture. Sustainable intensification of agroecosystems, producing more per unit consumption of essential resources, must consider judicious management of hydrological and biogeochemical cycles (C, N, P, S). The soil C pool must be managed and enhanced to offset anthropogenic emissions, and mitigate/adapt to the climate change. The pace of adoption of recommended land use and soil‐/plant‐/animal‐management practices can be kept at par with advances in scientific knowledge through continuous dialogue between scientists on the one hand and policy makers / land managers on the other to translate research data into policy and action plans.     

Large‐scale soil maps and a supplementary database for land use planning in Estonia

A soil map at the scale 1:10,000 serves as a major important document for land owners and local governments, which allows them to use soil information in their daily activity. The intensity of exploitation of soil maps will increase when the very map and its legend are supplemented, within colored and indexed polygons, with information about soil texture and reaction by layers, but also about the thickness and characterization of the epipedon, quality indices for soil assessment, classes of stoniness, and prevalent fractions of stones, erosion risk, etc. Special maps of agronomical status, with a list of proper measures for improvement of soils and their associations, should form a regular component of large‐scale mapping. As decrease in arable land and increase in the forest area are common trends in land use, these maps and general soil data should serve as the fundamental source of information for decision making concerning land use. Data indicating the suitability of any soil for any crop should be entered in a database. Application of GIS on any level of national economy, digitization of a large‐scale soil database and making it accessible to land users would allow to expand the amount of available information for each soil map polygon.     

土地整理项目空间分异及其与经济发展的耦合关系

该文在对重庆市土地整理项目实施概况及其空间分异进行系统分析的基础上,探讨了经济发展与土地整理项目耦合关系,并以重庆市为例进行实证研究。结果表明：根据不同的新增耕地率,可把重庆市区县级投资土地整理项目划分为4个类型：整理型、整理开发型、开发整理型、开发型;按照新增耕地单位面积投资额的高低可划分为4个类型：高投资型、中等投资型、投资偏低型以及低投资型;实施规模单位面积投资额与GDP年均增长率、人均GDP年均增长率的耦合曲线类型为复合曲线;新增耕地单位面积投资额与GDP年均增长率、人均GDP年均增长率的耦合关系呈“S”型变化趋势。区县级投资土地整理项目工程建设标准与区县经济发展关系并不明显且新增耕地单位面积投资额增长速度呈减缓趋势,出现了农用地以及基本农田整理力度和项目实施规模加大而实施规模单位面积投资额降低的“表象”。通过对重庆市经济发展与土地整理的耦合规律研究,为重庆市土地整理事业健康发展提供理论参考。     

资源环境硬约束下中国耕地休耕优先区识别

为厘清全国耕地资源环境本底并识别中国休耕优先区,该研究从生态保护红线、土壤污染状况、地下水超采和耕地质量等级等4个维度,运用生态保护红线划定、内梅罗综合污染指数、地下水水位变幅等方法系统分析中国耕地资源环境胁迫因子空间格局及分异特征,并构建多准则休耕规则识别不同情景下中国休耕规模及优先区的空间分布。结果表明：1）中国北方划入生态保护红线范围内耕地面积远高于南方,划入一级生态保护红线范围内耕地占3.57%;2）中国耕地重、中度污染面积分别占1.23%和2.31%,南方整体污染高于北方且南方呈局部分散、北方呈点状集聚格局;3）地下水超采区集中于河北、河南、吉林和江苏,重度超采区仅占0.68%;4）耕地质量总体一般,劣等、低等耕地面积分别占3.69%和14.0%,北方明显高于南方且大范围分散分布。依据多准则休耕规则综合评判,划入休耕优先区占全部耕地的23.70%,比食品安全优先、产能损失最小和生态保护优先3种情景分别高8.40%、4.18%和3.12%,其中禁植必休区、限植休耕区和重点轮休区分别为1.95%、4.71%和6.18%。因此,必须从源头治理视角厘清耕地资源环境本底,权衡休耕的迫切性,为国家层面上休耕规划有效落地、污染休耕治理和耕地保护创新提供技术支撑。     

Assessing the Biophysical Impact and Financial Viability of Soil Management Technologies Under Variable Climate in Cabo Verde Drylands: The PESERA‐DESMICE Approach

Field trials have demonstrated the potential of soil conservation technologies but have also shown significant spatial–temporal yield variability. This study considers the Pan‐European Soil Erosion Risk Assessment – Desertification Mitigation Cost‐Effectiveness modelling approach to capture a greater range of climatic conditions to assess the potential effect of an improved agricultural management practice emerged from field trials as a promising strategy for enhancing food security and reducing soil and land degradation. The model considers the biophysical and socio‐economic benefits of the improved soil conservation technique (T3) – residue mulch combined with pigeon pea hedges and an organic amendment, against a local baseline practice (T0). The historic rainfall statistics and 50‐year rainfall realizations provide a unique time series of rainfall and an envelope of the potential crop yield. Envelopes of potential biomass production help express the agricultural risk associated with climate variability and the potential of the conservation measures to absorb the risk, highlighting the uncertainty of a given crop yield being achieved in any particular year. T3 elevates yield under both sub‐humid and semi‐arid climates with greater security for sub‐humid areas even though risk of crop failure still exists. The technology offered good potential to increase yields by 20% in 42% of the dryland area in Santiago Island and reduce erosion by 8·6 Mg ha⁻¹, but in terms of cost‐effectiveness, it might be prohibitively expensive for farmers lacking inputs. The findings can enable the assessment of policy options at larger scale or influence adoption of improved conservation measures under the climatic variability of the Cabo Verde drylands and resilience to future climate change. Copyright © 2016 John Wiley & Sons, Ltd.     

Microbial dynamics and natural remediation patterns of Fusarium‐infested watermelon soil under 3‐yr of continuous fallow condition

Long‐term monoculture of watermelon results in inhibited growth and decreased crop yields, possibly because of imbalance in microbial ecology caused by accumulation of the pathogen in soil. This results in serious problems in the economics of watermelon production. We investigated the build‐up of Fusarium in soil under watermelon cultivation and changes over 3 yr of fallow in a microcosm. We focused on changes in the microbial community of Fusarium‐infected soil, including the diversity of the microfloral species composition, and species abundance. Long‐term monoculture of watermelon leads to changes in microbial diversity and community structure. The microbes most readily cultured from infested soil were suppressed by watermelon wilt pathogen Fusarium oxysporum f. sp. niveum (FON). Of 52 isolated and identified culturable microbes, 83.3% of bacteria, 85.7% of actinomycetes, 31.6% of fungi and 20.0% of Fusarium sp. were inhibited by FON on bioassay plates. Prior to fallowing, infested soil was a transformed ‘fungus‐type’ soil. After 3 yr of fallow, the infested soil had remediated naturally, and soil microbial diversity recovered considerably. Abundance of dominant bacterial populations was increased by 118–177%, actinomycetes, fungi and FON were decreased by 23–32, 33–37 and 50%, respectively. The ratio of bacteria: actnomycetes: fungus: Fusarium sp. in infested soil changed from 24 000:100:4:1 prior to fallow to 57 000:100:3.5:1 after fallowing, nearer to the 560 000:400:8:1 ratio of healthy soil not used for watermelon cultivation. This suggests the ‘fungus‐type’ soil was converting to ‘bacteria‐type’ soil and that disrupted microbial communities in infested soil were restored during fallow.     

2000－2018年广西植被时空变化及其对地形、气候和土地利用的响应

广西是典型的喀斯特地区,其生态系统非常脆弱。为评估广西植被时空变化特征及其影响因素,该研究基于2000－2018年MODIS数据,利用最大值合成和趋势分析等方法,分析广西植被NDVI时空变化特征;基于相关分析等方法,结合地形因子、气候因子和土地利用数据,探讨了植被NDVI对地形、气候变化和土地利用的响应。结果表明：1）2000－2018年广西植被NDVI呈增加趋势,但空间差异显著,表现为北高南低,边缘高中间低。2）随着高程的增加植被NDVI呈现先增加再减少的趋势;随着坡度的增加植被NDVI呈先增加至稳定再减小的趋势;除无坡向以外,坡向的不同对植被NDVI影响不大。3）广西2000－2018年气温和降水对植被NDVI为正影响,平均复相关系数达到0.32。在不同土地利用类型上,植被NDVI对气候的响应是不同的。研究结果揭示了广西植被时空变化特征及其对地形、气候和土地利用的响应,能够为广西可持续发展和生态环境建设提供决策支持。