Progressive fragmentation of a traditional Mediterranean landscape by hazelnut plantations: The impact of CAP over time in the Langhe region (NW Italy)

Land use change is strongly modifying the traditional landscape of hilly productive Mediterranean sites. An example of these circumstances is the Langhe region (Piemonte, NW Italy), where woody plantations such as vineyards and orchards have been cultivated on hillslopes for centuries. In this paper we assess landscape changes occurred in the Diano study area (2651 ha) in the 1954–2000 period and we ascertain land use transition paths and rates of this rural ecosystem. Land use mapping obtained from object-oriented analysis of aerial photographs was used to quantify land use changes between 1954 and 2000. To examine the spatio-temporal patterns of land use change over time, a set of spatial statistics capturing different dimensions of landscape change was identified. An increase of landscape heterogeneity from 1954 to the present was observed due to the expansion of orchards and the fragmentation of field crops. A significant portion (55%) of current orchards surface is represented by former field crops, 24% by vineyards and 15% by forests. The strong expansion of hazelnut orchards concurred to the fragmentation of traditional rural landscape was dominated by vineyards, field crops and forests. Hazelnut orchards expansion was mainly located in places where grapes cultivation was less remunerative. A further expansion of hazelnut in the area should be planned, discussed and carefully monitored through change detection studies in order to avoid potential unsustainable use of the land.     

Owned or rented—does it matter? Agricultural land use change within farm properties,case studies from Norway

In Norway and many other countries agriculture has moved toward less, but bigger farms. Total agricultural area has not been much affected mainly due to land tenancy. In this study we used aerial photographs to map land use and land cover in agricultural areas at present and in the mid-sixties. Three study sites were chosen, representing areas of differences with respect to drivers of change and possible differences in their landscape outcome. Maps from the two periods were used to produce transition matrices for the three areas as well as within each farm property. Our main finding on acreage change is that fully cultivated land increases and pastures decreases. A novel feature in our study is that we also include land use changes within single properties. In all three places a large share of the fully cultivated land in the sixties remains fully cultivated land irrespectively of whether the land is in use by its owner or is rented. When we looked at increases of fully cultivated land, the results are mixed. In the less favorable region, ownership to land versus rented land helps explain the variation in gain of fully cultivated land as well as maintained total agricultural area. However, in the case study from the grain region, whether a farm property today is in use as own land or rented, do not help explain the variation in changes within the data sample of farm properties larger than one hectare.     

Designating tree crops as forest: Land competition and livelihood effects mediate tree crops impact on natural forest cover in south China

The Chinese government applies the term ‘tree crops’ (jingjilin) to a bundle of tree species with uses other than timber production, defining this category as a component of national forest statistics. Tree crops may displace either farmland or forestland, and can be a promising livelihood option for smallholders. The overall impact of this particular policy on natural forest growth remained unanswered. In the general expansion trend of tree cover in southern China, tree crops could compete for land with natural forests, their cultivation may pose environmental trade-offs with natural forest cover. However, in a context of large labor flows from countryside to cities, tree crops could provide promising opportunities for dealing with on-farm labor shortages and generating income for disadvantaged populations remaining in rural communities, then promoting remaining natural forest quality through alternative livelihoods process. There is a knowledge gap to thoroughly investigate tree crops’ impact on natural forest change both conceptually and empirically, especially a mechanism verification of the alternative livelihood hypothesis. Thus, we construct a framework assessing land use competition and alternative livelihood effects together to assess overall impacts of tree crop cultivation on natural forests. Our dataset combines forest resource inventory data and provincial social-economic factors for a panel analysis of contributions to change in natural forest cover, density, and stock in China’s biodiversity-rich southern provinces. Results show tree crop cover is negatively associated with natural forest extent, but positive associated with change in natural forest density, while the relationship with change in natural forest stock is insignificant. Further tests of mechanisms support the hypothesis that tree crops benefit disadvantaged rural populations, providing an alternative livelihood. Defining tree crops as forest in China obscures important patterns, particularly a trade-off between tree crops and natural forest cover and a possible synergy with natural forest density mediated by alternative livelihood processes. Policy makers should enact specific policies to incentivize natural forest recovery in the southern collective forest zone and reconsider the appropriateness of defining tree crops as forest. Concentration and intensification of tree crop production on suitable lands may have the potential to benefit both forests and impoverished populations.     

Drivers of land change: Human-environment interactions and the Atlantic forest transition in the Paraíba Valley,Brazil

Human societies constantly interact with the environment through mutual feedbacks and adaptations. The aim of this research was to analyze human and environmental dimensions so as to understand how the dynamic processes of land use and land cover change are contributing to the increase of forest cover observed between 1985 and 2011 in the Paraíba Valley, Brazil. The forestry sector, based on eucalyptus plantations, is given particular attention due to its role in these change processes. Multi-layer perception neural network (MPNN) models were adopted to evaluate the influence of independent variables in the process of the forest transition. Based on the model's results, we conclude that the process is conditioned by a set of biophysical and socioeconomic variables that operate during different historical periods and in different landscape settings. The proximity of Atlantic forest remnants was influential in the forest transition for the three periods analyzed: 1985–1995, 1995–2005, and 2005–2011. In the first period of change (1985–1995), topography was most influential. Between the periods of 1995–2005 and 2005–2011, the proximity to eucalyptus plantations was an important factor, indicating a high probability of native forest recovery occurring in the vicinity of these monocultural areas. The forest transition tends to occur in areas less suitable for agriculture at the outset, but as these areas are replaced by forest cover, socioeconomic drivers such as farm credit and economic development play important roles in forest recovery.     

Land-use dynamics in a Brazilian agricultural frontier region, 1985-2017

Increasing demands for essential human needs (e.g. water, food, and energy) put pressure on natural resources, intensifies land use competition, and create challenges regarding environmental conservation. Understanding such dynamics is instrumental for the implementation of public policies in a more rational and planned manner, ensuring a better balance between uses and the maintenance of natural habitats, as well as fulfilling the demands of a rapidly growing society. Within this scope, in this study we applied statistical sampling techniques to remote sensing data (Landsat images from 1985 to 2017) in order to retrieve information on the dynamics of land use in one of the most prominent agricultural frontier regions in the world. Specifically, we chose the Brazilian state of Goiás, located in the Cerrado biome, which is a biodiversity hotspot for its natural value and high endangerment level. Our results yielded estimates showing, in a first moment (1986 - 1996), the suppression of native vegetation concomitant with the expansion of pasture areas. From 1997 onward, this dynamic coexisted with the advance of annual crops and sugarcane over pasture areas (which serve as important land reserves). Our study corroborates the potential of using image-based statistical sampling to understand, in an efficient, agile, unbiased, and accurate manner, the dynamics and history of land uses in any region of interest. Likewise, the synergy between such low cost approach and other datasets (e.g. agricultural surveys) can increase the precision of land-cover and land-use assessments, complementing missing information and refining the identification of occupation patterns and trends. In particular, area estimates, as those generated in this study, can serve to quickly assess the outcomes of public policies focused on reducing deforestation rates and improving the use efficiency of areas already converted.     

Does demographic change affect land use patterns?: A case study from Germany

Recent demographic change, mainly characterised by a decreasing and ageing population, is seen as one of the main factors for future land use development in Europe. However, there is still insufficient evidence about the relationship between demographic changes and land use changes since quantitative studies dealing with these interactions are still rare. We aim to fill that gap by presenting the first comprehensive study that investigates statistical relationships and spatial differentiations between demographic and land use change for the whole of Germany. Our study is based on data for the period from 1995/1996 to 2003/2004. The results clearly show that in most growing regions in the West of Germany a correlation was found between land use, natural population growth and net-migration, whereas for land use change in the shrinking regions in the East of Germany economic variables are of noticeable importance. A cluster analysis reveals “gaining” and “shrinking” regions concerning both urbanisation and demographic change. Neither a decreasing nor an ageing population imply reduced land consumption for housing and transportation. Furthermore we found a decreasing settlement population density for almost all German districts regardless of population growth or shrinkage.     

Simulating the impacts of future land use change on soil erosion in the Kasilian watershed,Iran

Predicting soil erosion potential is important in watershed management. A rapidly growing Iranian population and climate change are expected to influence land use and soil sustainability. In recent years, northern Iran has experienced significant land use changes due to internal migration along the Caspian coast and conversion of forests and rangelands. Considering the effect of these changes in the future, the purpose of this study is to forecast land use patterns and investigate soil erosion scenarios using the Revised Universal Loss Equation and Markov Cellular Automata. Data from 1981 to 2011 were used as a baseline to estimate changes that might occur in 2030. The results reveal that the mean erosion potential will increase 45% from the estimated 104.52 t ha⁻¹ year⁻¹ in the baseline period. Moreover, the results indicate that land use change from forest area to settlements will be the most significant factor in erosion induced by land use change, showing the highest correlation among erosional factors. Projecting land use change and its effect on soil erosion indicate that conversion may be unsustainable if change occurs on land that is not suited to the use. The method predicts soil erosion under different scenarios and provides policymakers a basis for altering programs related to land use optimization and urban growth. Those results indicated the necessity of appropriate policies and regulations particularly for limiting land use changes and urban sprawl in areas of unfavorable soil erosion risk factors.     

基于生态足迹理论的湖北省耕地可持续利用分析

运用生态足迹模型分析了湖北省2005年各类土地的生态足迹及生态承载力,重点分析了1995～2005年全省及17个市(州)耕地生态足迹的动态变化过程;对湖北省耕地可持续利用状况进行了分析与评价;研究结果表明,湖北省人均耕地生态足迹和生态承载力都呈下降趋势,耕地的生态赤字出现小幅度波动,全省属于耕地不可持续类型;以2005年数据为依据,17个市(州)中,只有神农架林区表现为生态赢余,属于可持续类型,其他均属于不可持续类型.     

近10年崇州市土地利用变化基本特征与空间格局

[目的]土地利用变化研究是揭示土地利用对人类活动响应程度的重要途径,通过对其变化特征及空间格局的研究讨论人地关系在不同地域空间上的强度与作用模式。[方法]基于2002年、2014年TM/ETM+影像,在RS和GIS技术的支持下,采用人机交互图像处理方法提取了崇州市土地利用信息,应用土地利用动态度、土地利用程度、空间转移图谱、城市扩展指数、缓冲分析模型和方法对崇州市近10年来土地利用变化时空特征进行了研究。[结果](1)土地利用类型以林地、耕地、建设用地为主,建设用地动态度最大达到5.72;整体土地利用程度由254.25增长到260.93,各乡镇变动值差异较大。(2)土地空间转换面积达1.850 85万hm~2,占研究区总面积的16.94%;增长面积最大的图谱单元依次是新增建设用地、新增耕地和新增林地;建设用地、耕地、水体与高程、坡度之间负相关性显著,坡度0°~6°是人类活动最频繁的区域。(3)中心城区建设用地面积大幅增长,缓冲范围内建设用地面积增加了2 120.76hm~2,城市中心自河流向东、东南、东北3个方向扩展。[结论]崇州市土地利用整体处于快速发展时期,地域差异明显,受人类活动影响显著。     

The demise of swidden-fallow agriculture in an Atlantic Rainforest region: Implications for farmers’ livelihood and conservation

The Brazilian Atlantic Forest is widely recognized for its high levels of biodiversity and endemism. Its vast region concentrates also a large number of small farmers, who historically have been practicing swidden-fallow cultivation. Globally, there is contradictory evidence of the current fate of this traditional, integrated agricultural system, and the new land uses may have a strong impact on farmers’ livelihoods and ecosystem conservation. In this study, we assessed the land cover and land use change in a watershed where slash-and-burn cultivation was prevalent, aiming at understanding the drivers of change and discussing past and possible future impacts, including the perception of farmers on the drivers of land use change. We combined information gathered from interviews with 15 key informant farmers and from the analysis of remote sensing images for the years 1957, 1978 and 2011. Swidden-fallow cultivation has declined steadily since the 1950s. Part of the land was abandoned and forest succession was allowed to occur, increasing the total forest area; an apparently positive outcome. However, conversion to pastures and Eucalyptus plantations not only used much of the open land but also converted successional forests through deforestation, based on remote sensing. The willingness of farmers to grow more Eucalyptus and raise more cattle further increases concerns about the prospect for conservation. Our approach, combining remote sensing-based land change quantification and interviews, revealed to be complementary, allowing a better understanding of the past and possible future scenarios for the land use dynamics.     

经济高速发展时期河南省土地利用变化分析研究

以河南省为研究区,对不同年份的土地利用数据进行分类系统整合,在此基础上,对河南省1996~2009年土地利用类型进行了对比分析,分析得出耕地、城镇村及工矿用地、林地、交通运输用地面积在增加,园地、草地、水域及水利设施用地、其它土地面积在减少,在各类土地类型转换中,林地是变化最为激烈的土地利用类型,其次是其它土地,变化最稳定的地类是交通运输用地,其次是耕地。     

Integrating strict protection and sustainable use areas to preserve the Brazilian Pampa biome through conservation planning

Biodiversity conservation planning must be ecosystem-specific and take into account human needs as food production. The Pampa biome is a temperate grassland with high species richness and with an important role in food production in South America. Here we present the first formal Systematic Conservation Planning for the Brazilian part of the Pampa, which is the least protected biome in Brazil. We aimed to build conservation scenarios where at least 17 % of the biome area were protected, following the 11^th Aichi target for terrestrial lands protection according to the Convention on Biological Diversity. Our conservation targets were the vegetation types of this biome. Three scenarios were built varying in their proportions of strict protection (SP) and sustainable use areas (SU): Permissive scenario (5 % SP, 12 % SU); Intermediate scenario (10 % SP, 7 % SU) and Restrictive scenario (15 % SP, 2 % SU). Urban and rural areas, as well as bovine and ovine density, were used as prioritization costs, aiming to minimize possible conservation conflicts. Four main clusters of priority areas to protect the vegetational diversity can be observed in all scenarios and should be considered when implementing future protected areas in this threatened biome. Sustainable use areas are suitable for low-density livestock raising, combining biodiversity protection and food production, but strictly protected areas are still important to species most affected by livestock. The combination of strict protection and sustainable use areas can be effective in similar biomes. It should be considered in future international negotiations, such as the 2020 Conference to be held in Beijing, opening new strategies to achieve the 17 % of land protection. We expect that this Systematic Conservation Planning reinforces the recently started scientific discussion regarding the conservation of non-forest ecosystems in Brazil.     

泰安市土地利用动态变化研究

在RS和GIS技术支持下,以1987年和2006年两期TM遥感影像为数据源,采用土地利用变化幅度和土地利用转移矩阵,研究了泰安市土地利用类型的数量变化和转变特征,分析了其变化的驱动因素.结果表明,1987-2006年间,耕地的变化幅度最大,面积减少31193 hm2;正变化率最大的是建成区为260.3%,主要由耕地和村...     

莫莫格自然保护区土地利用变化及驱动力分析

基于莫莫格自然保护区1989、2000、2007、2012年4期LandsatTM遥感影像数据,运用遥感、地理信息系统以及景观生态学方法,对研究区土地利用与景观格局动态变化进行定量分析。结果表明:在过去的二十年里,莫莫格自然保护区的土地利用方式发生了显著变化,耕地净增加14403.02hm2,其中林地、草地对耕地的增长贡献最大;而湿地则不是单调变化的,其中1989年~1997年湿地面积减少24359.14hm2,1997年~2007年增加6009.237hm2,2007年~2012年增加2983.47 hm2;此外,在研究时段内研究区域的景观异质性有波动性变化,景观格局变化趋势与土地利用变化规律趋同。     

Geographic disparities in rural land appreciation in a transforming economy: Chile, 1980 to 2007

This paper reports on a research effort to gather and analyze rural land value data during a period of unprecedented growth in Chilean agriculture. This information is important to understand the geographical distribution of gains associated with the transformation of the rural sector during a period of rapid development, trade liberalization and transition toward a predominant emphasis on export earnings in agriculture. A large set of data of rural land transactions for 1980, 1990, 1997 and 2007 were collected from a sample of land registry offices. Results show notable declines in the physical size of transactions, significant average annual rates of increase in real per-hectare values, and a small-parcel premium for rural land associated with non-farm land use. Overall real land values have increased faster than the average annual growth rates in the agricultural sector’s value added, suggesting that land owners have gained proportionately more than other claimants to sectoral income. Tests show significant geographic disparities in annual rates of land appreciation across regions and municipalities. Consistent with differential net gains due to integration into world markets and the geographic heterogeneity of suitability for different land uses, northern areas, with greater emphasis on export-oriented crops, have experienced the highest average rates of annual real per-hectare value growth, in the order of 7 percent, while southern areas, emphasizing traditional crops and pastures/livestock, have experienced growth rates of half that. Geographic disparities are also explained by proximity to urban population and income centers.     

Mapping changes in land use/land cover and prediction of future extension of bowé in Benin,West Africa

Desertification and land degradation are worldwide problems affecting soil, vegetation and the livelihoods of rural populations. Bowal (plural bowé) is a particular form of degraded land that occurs in tropical regions and leads to the exposure of ferricretes, which are unsuitable for farming. Bowé are more common on farmland and degraded savanna. Changes in land use/land cover were used to map a region of 6.7 million ha in northern Benin, West Africa in 1975, 1990 and 2010. The changes observed during these periods (1975–1990, 1990–2010 and 1975–2010) were used to predict the occurrence of bowé in the period up to 2050 using Markovian chain analysis. The results showed a considerable change in land use/land cover during the three periods. The types of land on which bowé occur (farmland and degraded savanna) increased in northern Benin by 5.4% per year during the period 1975–1990 and 9.5% per year during the periods 1990–2010, while the natural vegetation (forest, woodland and tree savanna) decreased by the same amount. The future scenarios also predicted the same trend. In the period 1975–1990, 1.28 million ha (26%) of natural vegetation was converted to degraded savanna and farmland while 2.23 million ha (53%) of natural vegetation was converted to degraded savanna and farmland in the period 1990–2010. Based on the dynamics recorded during the period 1975–1990 and 1990–2010 respectively, a total of 1.28 million ha (26% of the natural vegetation that was present in 1975) and 1.29 million ha (31% of the natural vegetation that was present in 1990) will be converted to farmland and degraded savanna in the study area by 2050.Thus bowalization will persist and increase in the period up to 2050. The natural vegetation could disappear if protection and restoration measures are not taken. It is thus important to take measures to stop the degradation and to implement programs to restore soils on bowé based on the soil and water conservation techniques used on highly degraded West African soils, such as zaï pit and stone rows with grass strips. Some native plants species adapted to bowalization and resistant to climate change in northern Benin (e.g. Asparagus africanus, Andropogon pseudapricus and Combretum nigricans) should be used in association with soil and water conservation techniques on bowé.     

Are forest plantation subsidies affecting land use change and off-farm income? A farm-level analysis of Chilean small forest landowners

Forest plantations have increased rapidly in the last three decades, to a large extent due to direct and indirect financial incentives. At the farm level, forestry incentives can affect the investment decisions of small forest landowners and bring socioeconomic externalities or unintended effects associated with farm management. The purpose of this study is to assess the ex post impacts of a forestry subsidy on land use changes and off-farm income experienced by Chilean small forest landowners. A structural equation mediation model (SEM) was estimated using a time frame of 15 years (1998–2013). To reduce the selection bias, propensity score matching (PSM) was performed prior to the estimation of the SEM. Results indicate that the subsidy had a significant effect on land use changes, as it increases forest plantations and replaces pastures primarily, but also crops and native forest to a lesser extent. In addition, beneficiaries of the subsidy had a marginal increase in off-farm income not explained by the increase in forest plantation.     

Changes in land use, land tenure, and landscape fragmentation in the Tijuana River Watershed following reform of the ejido sector

Changes in land use and land tenure can influence both physical fragmentation and ownership fragmentation of landscapes, with implications for biodiversity. In this study, we evaluated changes in land use and land tenure in the Tijuana River Watershed, a region of high biodiversity and endemism, following the implementation of a new Agrarian Law which allowed for privatization and sales of communal land (ejidos) beginning in 1992. In order to understand changes in land use and cover, we constructed maps from aerial photographs and Aster images and measured changes between 1994 and 2005. In order to understand changes in land tenure, we collected data from Mexican government sources on ejido land size, ownership, and sales, and we conducted 55 structured interviews with ejidatarios in the watershed. Our results demonstrate that land-use/cover change between 1994 and 2005 was dominated by an increase in urban area and grasslands, and a decrease in coastal sage scrub, chaparral, and, to a lesser degree, agriculture. In particular, the conversion of coastal sage scrub has left a far more fragmented landscape than existed in 1994. In addition, most of the ejidos in the watershed, as well as individuals interviewed, had participated in some stage of the land certification and titling process allowed by the new Agrarian Law, resulting in substantial changes in land tenure. However, land tenure security appeared to play a larger role than a desire to sell land and, contrary to studies from other regions, full title to the land was obtained in a range of urban and rural settings, rather than primarily on land closest to urban zones. Our results suggest that past predictions regarding future urban growth and fragmentation of native vegetation in the region have proven accurate and highlights regions of change that merit further study.     

基于耕地多功能权衡与协同分析的耕地利用转型研究——以北京市为例

[目的]探究耕地隐性形态变化,丰富耕地利用转型研究的形态视角。[方法]土地系统功能权衡度(LFTD)模型,灰色关联度分析法。[结果](1)2005—2016年北京市耕地多功能性呈现不同变化趋势。生产和社会保障功能为下降态势,生态功能经历U型变化,文化功能为持续上升状态。(2)根据功能层次性将北京市耕地多功能变化分为3个阶段:2005—2008年耕地转型前期,生产和社会保障功能为主导;2008—2014年转型期,多功能间发生复杂作用;2014—2016年转型后期,文化和生态功能为主导。(3)耕地多功能随阶段变化经历了权衡协同关系持平到以权衡关系为主导再到权衡协同关系持平的过程。3阶段主导功能变化及转型期生态、文化功能和生产、社会保障功能间复杂的权衡关系共同佐证了北京市于2014年实现了耕地功能层面转型。(4)3阶段影响因素关联性趋势变化显示第一产业比重、人均固定资产投资、农民人均纯收入和人均GDP是耕地转型期显著影响因素。[结论]耕地隐性形态变化可深层次显化耕地利用转型,为耕地可持续利用提供参考。     

大连旅顺区土地利用及地表温度时空分异研究

伴随着城市空间的快速扩展,土地利用发生巨大转变,城市气候和生态环境问题日益突出。本文以大连旅顺区为例,基于2005年和2016年两期数据,单窗算法进行地表温度反演,并通过GIS空间分析方法,探讨旅顺区土地利用及地表温度时空分异特征。2005-2016年,旅顺区建设用地、水域面积呈增加趋势,面积分别增加了9.51 km2、13.19 km2;耕地、林草地及其他用地呈减少趋势;11年间,旅顺区地表温度整体逐渐升高;各用地的地表温度呈现出“建设用地和其他用地>耕地和园地>林草用地和水域”状态。