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1.

Explorations of future land use change are important to understand potential conflicts between competing land uses, trade-offs associated with particular land change trajectories, and the effectiveness of policies to steer land systems into desirable states. Most model-based explorations and scenario studies focused on conversions in broad land use classes, but disregarded changes in land management or focused on individual sectors only. Using the European Union (EU) as a case study, we developed an approach to identifying typical combinations of land cover and management changes by combining the results of multimodel simulations in the agriculture and forest sectors for four scenarios from 2000 to 2040. We visualized land change trajectories by mapping regional hotspots of change. Land change trajectories differed in extent and spatial pattern across the EU and among scenarios, indicating trajectory-specific option spaces for alternative land system outcomes. In spite of the large variation in the area of change, similar hotspots of land change were observed among the scenarios. All scenarios indicate a stronger polarization of land use in Europe, with a loss of multifunctional landscapes. We analyzed locations subject to change by comparing location characteristics associated with certain land change trajectories. Results indicate differences in the location conditions of different land change trajectories, with diverging impacts on ecosystem service provisioning. Policy and planning for future land use needs to account for the spatial variation of land change trajectories to achieve both overarching and location-specific targets.

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2.
The drastic socio-economic and political changes that occurred after the breakdown of socialism in Eastern Europe triggered widespread land use change, including cropland abandonment and forest cover changes. Yet the rates and spatial patterns of post-socialist land use change remain largely unclear. We used Landsat TM/ETM+ images to classify land cover maps and assess landscape pattern changes from 1990 to 2005 in Argeş County, Southern Romania. Cropland abandonment was the most widespread change (21.1% abandonment rate), likely due to declining returns from farming, tenure insecurity, and demographic developments during transition. Forest cover and forest fragmentation remained remarkably stable during transition, despite widespread ownership transfers. Cropland abandonment provides opportunities for increased carbon sequestration, but threatens cultural landscapes and biodiversity. Continued monitoring is important for assessing whether abandoned croplands will eventually reforest or be put back into production and to better understand the consequences of post-socialist land use change for ecosystems and biodiversity.  相似文献   

3.
基于CLUE-S模型的重庆市主城区土地利用情景模拟   总被引:3,自引:0,他引:3  
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。  相似文献   

4.
This paper assesses the relative importance of socioeconomic factors linked to fire occurrence through the simulation of future land use/land cover (LULC) change scenarios in the Madrid region (Spain). This region is a clear example of the socioeconomic changes that have been occurring over recent decades in the European Mediterranean as well as their impact on LULC and fire occurrence. Using the LULC changes observed between 1990 and 2006 as a reference, future scenarios were run up to 2025 with the conversion of land use and its effects model. Simultaneously, the relationship between LULC arrangement (interfaces) and historical fire occurrence was calculated using logistic regression analysis and used to quantify changes in future fire occurrence due to projected changes in LULC interfaces. The results revealed that it is possible to explain the probability of fire occurrence using only variables obtained from LULC maps, although the explanatory power of the model is low. In this context, border areas between some LULC types are of particular interest (i.e., urban/forest, grassland/forest and agricultural/forest interfaces). Results indicated that expected LULC changes in Euro-Mediterranean regions, particularly given the foreseeable increase in the wildland–urban interface, will substantially increase fire occurrence (up to 155 %). This underlines the importance of future LULC scenarios when planning fire prevention measures.  相似文献   

5.
China is a key vulnerable region of climate change in the world. Climate warming and general increase in precipitation with strong temporal and spatial variations have happened in China during the past century. Such changes in climate associated with the human disturbances have influenced natural ecosystems of China, leading to the advanced plant phenology in spring, lengthened growing season of vegetation, modified composition and geographical pattern of vegetation, especially in ecotone and tree-lines, and the increases in vegetation cover, vegetation activity and net primary productivity. Increases in temperature, changes in precipitation regime and CO2 concentration enrichment will happen in the future in China according to climate model simulations. The projected climate scenarios (associated with land use changes again) will significantly influence Chinese ecosystems, resulting in a northward shift of all forests, disappearance of boreal forest from northeastern China, new tropical forests and woodlands move into the tropics, an eastward shift of grasslands (expansion) and deserts (shrinkage), a reduction in alpine vegetation and an increase in net primary productivity of most vegetation types. Ecosystems in northern and western parts of China are more vulnerable to climate changes than those in eastern China, while ecosystems in the east are more vulnerable to land use changes other than climate changes. Such assessment could be helpful to address the ultimate objective of the United Nations Framework Convention on Climate Change (UNFCCC Article 2).  相似文献   

6.
Farming communities are increasingly expected to manage their agricultural activities in ways that ensure sustainable flows of a wide range of ecosystem services for society. The land use and management choices that farmers make are dependent upon their socio-economic characteristics and background, and in turn have important implications for the landscape and associated ecosystem services. Thus, a better understanding about the linkages between the characteristics of farmers, farm management and land use is important for managing multifunctional agro-ecosystems. In this paper, we first develop a typology of farmers for Torrealvilla catchment in Murcia, Spain, according to the characteristics of their households and farm management (e.g. the farmer’s age, household income, water access, land tenure and farm labour). This analysis distinguishes six types of farmers. Secondly, we analyse the link between farmer typology and the farmers’ responses to a number of scenarios. The scenarios describe different likely changes to agriculture in the catchment in terms of environmental constraints (irrigation water availability and rainfall pattern) and environmental policy regulation (water taxation and subsidies). This exercise enables us to explore the range of future land use changes that are likely to occur in the study area. The results indicate that: rain-fed agriculture is expected to experience gradual but extensive abandonment; vegetable/fruit farming and pig/animal rearing are likely to stagnate or even decline; and growing of grapes is likely to expand. Thirdly, we qualitatively evaluate how future land use changes are likely to affect key ecosystem services in the study area including future agricultural production and associated local income generation, erosion control, maintenance of the groundwater table and various cultural services associated with a heterogeneous agro-ecosystem. Particular changes such as expansion of grape production will increase food production and local income at the cost of further depletion of the aquifer and increased risk of salinisation. The outcomes of the study highlight that, to be effective, the design of agri-environmental schemes and other government interventions (e.g. specific compulsory regulations on farming practices and associated water use) should carefully take into account the characteristics of the farmers within the area of interest, their land uses and the possible diversity of responses to policy and environmental drivers. Opportunities exist for future studies quantifying the extent of the impacts of ecosystem service provision through formal models combining farmers’ land use decision-making and spatially explicit modelling of landscape processes.  相似文献   

7.
Understanding the importance of cross-sectoral implications of climate and socio-economic change in Scotland is essential for adaptation policy. This study explored the direct and indirect sectoral impacts of future change using the CLIMSAVE Integrated Assessment Platform. There is great spatial diversity in projected impacts across Scotland, and increasing uncertainty in the direction of change of impacts from the national to regional scale associated with climate uncertainty. Further uncertainty associated with socio-economic change results in 6 out of 13 indicators (artificial surfaces, biodiversity vulnerability, forest area, land-use intensity, irrigation usage and land-use diversity) with robust directions of change at the national scale and only three (artificial surfaces, forest area and irrigation usage) that are robust across all regions of Scotland. Complex interactions between socio-economic scenario assumptions (e.g. food imports, population and GDP), climatic suitability and agricultural productivity and profitability lead to significant national and regional changes in the distribution and extent of land cover types, with resultant cross-sectoral interactions with water, forestry and biodiversity. Consequently, stakeholders characterised robust adaptation policy options, within the CLIMSAVE participatory process, as those beneficial to society (and the country) in all scenarios, irrespective of the direction of change of the impacts. The integration in CLIMSAVE of a participatory scenario development process and an integrated participatory modelling framework has allowed the exploration of future uncertainty in a structured approach and better represented the importance of qualitative information and the social and institutional contexts within adaptation research.  相似文献   

8.
The present study used temporal remote sensing data for 1990, 2001 and 2006 to assess spatio-temporal patterns of forest cover changes in Shiwalik range of the Himalaya, Dehradun forest division. Forests are innately associated to human well-being. However, with the increasing anthropogenic activities, deforestation has increased. Quantitative change analysis of the forest cover for the past two decades provides valuable insight into the forest conservation vis-à-vis anthropogenic activities in the region. Spatio-temporal datasets along with biotic and abiotic variables provide opportunities to model the forest cover change further. The present study investigates forest cover change and predicts status of forest cover in the Dehradun forest division. Land Change Modeller (LCM) was used to predict status of forest cover for 2010 and 2015 using current disturbance scenarios. Comparing actual LULC of 2006 with the predicted LULC of 2006 validated change prediction model and agreement was 61.03%. The forested areas are getting degraded due to anthropogenic activities, but deforestation/degradation does not contribute much in expanding urban area. Agricultural areas and fallow lands are the main contributors to increased urban area. The study demonstrates the potential of geospatial tools to understand spatio-temporal forest cover change and generate the future scenarios.  相似文献   

9.
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.  相似文献   

10.
土地利用/覆被变化(LUCC)对流域水文过程具有重要的长期影响作用。针对土地利用覆被变化对大型流域水文过程的影响程度,利用构建的长江流域分布式水文模型分析了土地利用变化情景下的水文效应特征。结果显示:分布式水文模型综合考虑了下垫面土壤、坡度、植被等特征,可以较好的反映降水发生后水分在不同土壤、植被和地形条组合件下,蒸散、地表和地下径流等组分的运移过程。根据不同土地覆被类型的径流成分差异,以及长江流域实际可供调节的土地利用方式,流域现有土地利用格局中农林地依然具有较大的转换空间。根据典型流域中预设的农林地转换情景下的径流效应看,各种情景虽然对流域径流总量变化影响较小,但对蒸散、地表径流和基流可以产生显著影响。其中,林地增加使基流最高提升超过15%,同时可使地表径流下降近5%,两者对蒸散的改变在1%左右,对径流总量变化幅度则只有0.7%左右。不同情景下的水文响应模式反映了未来土地利用调整的水文效应,因此可以基于不同的径流效应,开展有利于综合发挥流域持水能力的空间规划,提升林地所占比重。  相似文献   

11.
基于CLUE-S模型的重庆市渝北区土地利用变化动态模拟   总被引:3,自引:0,他引:3  
以重庆市渝北区为研究区域,运用CLUE-S模型,结合Logistic回归分析,分别以2007年和2009年为基期,对渝北区2013年土地利用情况进行模拟研究,在此基础上构建了渝北区2013~2020年3种不同情景的土地利用变化模式,模拟了3种情景模式下渝北区在2020年的土地利用空间分布格局。结果表明:(1)两期模拟的正确率分别达到了92.26%和94%,Kappa系数值分别为90.32%和92.5%,均取得了较好的模拟效果,说明CLUE-S模型适用于渝北区的土地利用空间格局变化的模拟研究,具有较好的模拟区域土地利用时空变化的能力;(2)地形、国道、省道、高速公路等主要道路、河流、城镇和村庄是影响渝北区土地利用空间格局变化的重要驱动因素;(3)在3种情景模式中,主要的用地格局变化均发生在两江新区,区内建设用地总体呈现向东北部扩张的趋势,表明区域经济社会发展政策对用地类型的变化具有较大的影响;(4)从促进城乡统筹和谐发展、土地节约集约利用、生态环境显著改善和保护耕地的区域发展目标而言,情景模式2为较为合理的发展模式。研究结果可为决策部门在土地可持续利用和土地管理方面提供参考依据。  相似文献   

12.
长江上游不同地形条件下的土地利用/覆盖变化   总被引:5,自引:1,他引:4  
基于1〖DK〗∶10万的1980、2000和2005年的土地利用/覆盖数据和90 m分辨率的DEM数据,采用转移概率矩阵和地形 面积频度方法,分析了1980~2005年长江上游地区不同地形因子条件下的土地利用/覆盖变化。结果表明:1)1980~2000年,草地、林地和农业用地面积变化趋势与2000~2005年相反。后5 a,可能由于退耕的土地出现反弹现象增多,草地和林地面积出现缩减而农业用地面积增加。两个分析时段主要的土地利用/覆盖类型变化趋势类似,包括农业用地向林地和草地的转化,林地向农业用地的转化以及草地向裸地的转化。2)农业用地和城镇用地主要分布于低海拔区而林地、草地则主要分布于高海拔区。低海拔区主要是退耕还林和城市化过程。高海拔区主要是林地的退化消失和草地退化沙化过程。3)农业用地在坡度段10~25°所占面积比例最大。林地用地面积比例随坡度变陡呈现规则递增,城镇用地分布趋势与之相反。近年裸地趋向分布于缓坡区。坡度0~5°的区域主要是草地退化沙化过程;5~10°坡度段主要是退耕还林过程;大于10°的区域造林工程与森林退化并存。4)各种土地利用/覆盖类型对不同坡向的适宜性相差不大。各种坡向上土地利用/覆盖类型变化类似.  相似文献   

13.
采用基于最大似然法的监督分类方法对四川省马边彝族自治县1988年和2001年两期Landsate5 TM影像进行解译,利用单项土地利用动态指数〖WTBX〗(LUDI)、双向土地利用动态指数(Ki)以及土地利用类型转移矩阵(Cx×y)〖WTBZ〗等定量分析方法分析解译结果,得到马边县13年间土地利用/覆被动态及转移特征,并对可能的生态影响进行了分析预测。结果显示:①次生林面积增加,针叶林面积有所下降,灌草地被农田大量取代;②城镇及居民点和次生林的动态最为活跃,转入面积明显高于转出面积;③中山区和亚高山区林地构成发生变化,高山草甸面积有所萎缩,河谷区的阔叶林带被次生林大量取代,低山河谷区的土地破碎化程度增加。研究表明,13年间马边土地利用/覆被变化具有动态高、转换活跃、空间性强以及人为活动干扰影响明显等特点。其中,低山丘陵区的灌草坡大量被农地替代、中山区和亚高山区次生林面积扩大应该作为生态退化的信号加以重视。另外,气候变化对马边森林植被演替可能产生的影响应在今后进行深入的分析研究  相似文献   

14.
There is broad consensus that land use/cover has changed in central Europe over millennia. However, few studies have addressed the roles of the anthropogenic (socio-economic) and natural (biophysical) factors driving these changes over shorter periods (e.g., 100 years). In this study, we analyse the determinants of land cover composition at three discrete time periods (c. 1780, 1890, and 2000). We hypothesise that different anthropogenic and natural factors are the determinants of the main land cover types (arable fields, grasslands, and forests) and that the effects of natural and anthropogenic factors on the main land cover types differ among landscapes with highly dynamic and more stable forest-open land distributions. The study was carried out in the Uckermark region located in northeastern Germany. We compiled data on natural and anthropogenic factors (e.g. forest cover and number of inhabitants) of 65 municipalities in four landscape sections of equal size (10 × 10 km). Landscape sections were selected to reflect different dynamics (high/low) in conversion from forest to arable fields or grasslands and vice versa from 1780 to 2000. Averaged linear mixed-effect models explained between 7.5 and 81.2 % of the variance. The unique effect of anthropogenic factors varied from 2.1 to 18.7 % and that of natural factors varied from 0.2 to 43.4 %. In four of six models that included both types of factors, the natural factors were more influential than the anthropogenic factors. Except in three cases, anthropogenic and natural factors showed opposite effects on land cover types in more dynamic and more stable windows. Though the Uckermark region has been influenced by human activity for thousands of years, natural factors were a major determinant of land cover composition during all time periods, whereas anthropogenic factors became more important only during the latest time period under investigation.  相似文献   

15.
基于Dyna-CLUE模型的太湖流域建设用地空间扩张模拟   总被引:1,自引:0,他引:1  
从区域尺度模拟建设用地空间扩张是理解和解释区域土地利用变化过程与趋势的有效途径之一。基于Dyna-CLUE模型,通过1985年以来5个时段太湖流域遥感影像数据及自然与社会经济数据提取先验转换规则,模拟未来太湖流域在耕地保护、生态保护与综合保护3种不同情景模式下建设用地空间增长过程。结果显示:3种模拟情景下Kappa 系数均大于0.75,具有较高的一致性,表明Dyna-CLUE模型在太湖流域建设用地空间扩张模拟中有较强的适用性;3种情景下,综合保护情景下建设用地扩张模拟精度最高;2020与2030年流域建设用地扩张均以大城市周边为主导,其中2010~2020年扩张总量位居前列的城市依次为上海、嘉兴、无锡和湖州等,而2020~2030年依次为嘉兴、苏州、上海和无锡等。2020年、2030年建设用地空间扩张模拟结果基本符合太湖流域建设用地空间扩张的趋势。研究方法及模拟结果相对可靠,以期为未来太湖流域城市化进程中的土地利用规划实施,特别是土地利用宏观需求的空间配置提供一定的借鉴与参考  相似文献   

16.
Loss of forest cover is a likely consequence of climate change in many parts of the world. To test the vulnerability of eucalypt forests in Australia’s island state of Tasmania, we modelled tree canopy cover in the period 2070–2099 under a high-emission scenario using the current climate–canopy cover relationship in conjunction with output from a dynamically downscaled regional climate model. The current climate–canopy cover relationship was quantified using Random Forest modelling, and the future climate projections were provided by three dynamically downscaled general circulation model (GCM) simulations. Three GCMs were used to show a range of projections for the selected scenario. We also explored the sensitivity of key endemic and non-endemic Tasmanian eucalypts to climate change. All GCMs suggested that canopy cover should remain stable (proportional cover change <10 %) across ~70 % of the Tasmanian eucalypt forests. However, there were geographic areas where all models projected a decline in canopy cover due to increased summer temperatures and lower precipitation, and in addition, all models projected an increase in canopy cover in the coldest part of the state. The model projections differed substantially for other areas. Tasmanian endemic species appear vulnerable to climate change, but species that also occur on the mainland are likely to be less affected. Given these changes, restoration and carbon sequestration plantings must consider the species and provenances most suitable for future, rather than present, climates.  相似文献   

17.
In the study of land-use and land-cover change as an important contributor to regional environmental change, linking household level land-use decisions to particular land-cover patterns has been an enduring challenge. The frequent conflation of land use and land cover has been appropriate and fruitful in regions where extractive activities are common, but the decoupling of household characteristics from land-cover choices in exurban landscapes may require that the two be treated separately. This research employs the concept of a land-use portfolio, defined as a unique combination of land use types, and land cover derived from remote sensing to examine the relationship between land use and land cover at the parcel scale. Data on the type and spatial organization of land use were collected for individual parcels through sketch maps constructed by land owners and then described quantitatively using GIS and spatial metrics from landscape ecology. The results of this analysis suggest that in the naturally forested region of south-central Indiana, parcels are frequently managed as multiple types of land use thereby supporting the portfolio approach. Generally, land-management complexity is related to land-cover fragmentation, but the strength of this relationship varies across portfolio types. In addition, substantial amounts of forest land cover occur in non-forest land uses further supporting the need to treat the two separately to accurately link land use intentions and land cover outcomes.  相似文献   

18.
There has been a significant lack of land cover change studies in relation to deforestation in the Democratic People’s Republic of Korea (North Korea). The purpose of this study is to characterize deforestation in North Korea through land cover change trajectory and spatial analysis. We used three 30-m gridded land cover data sets for North Korea representing the conditions of the late 1980s, 1990s, and 2000s, respectively, as well as a digital elevation model. We examined the land cover trajectories during the two decades, i.e., which land cover became which at the pixel level. In addition, we calculated topographic characteristics of deforested pixels. Major findings from the study are summarized as follows: (1) net forest loss in North Korea was negligible in the latter decade compared to the former (>5000 km2), whereas other land cover changes were still active; (2) as a result of deforestation, forest land cover became mostly agricultural, particularly in the latter decade (95 %); (3) expansion of agricultural land cover continued during the time, increasing by >42 %; and (4) elevation and slope of deforested areas decreased slightly in the latter decade. The key contribution of the study is that it has demonstrated which land cover became which at the 30-m pixel level, complementing existing studies that examined overall forest stock in North Korea.  相似文献   

19.
Land use and cover conversions as well as climatic factors drive current and future threats to freshwater systems. Research from the United States and across the globe has focused on already threatened and degraded freshwater systems, whose recovery requires significant investments. Attention must also be directed to monitoring freshwater systems that may appear robust, yet are likely to face enhanced vulnerabilities in the future due to climate and land use and cover changes. Such proactive monitoring can help identify problems early and provide potential solutions. In this study, we consider the case of Sebago Lake and its watershed in southern Maine; a region that has experienced significant population growth and development activity. Land use, socioeconomic change and water quality trends are monitored over a 20-year period using Landsat imagery, census, water quality and precipitation data. Our results indicate that Developed Land within the watershed has increased from 5.4 % of the total land area in 1987 to 8.9 % in 2009 with associated increases in population and housing activity. Sebago Lake’s water quality indicators from 1990 to 2010 show a directional trend concomitant with this change. The increase in Developed Land is likely to place additional pressures on water quality in the future. The analysis also indicates that precipitation trends play an important role in water quality variability for Sebago Lake. Predicted changes to climatic factors including enhanced spring time precipitation or earlier ice-out conditions combined with further land use change may play an influential role in determining water quality. The analysis highlights emerging areas of concern and reiterates the essential role of proactively monitoring vulnerable systems to help mitigate future threats.  相似文献   

20.
基于SLEUTH模型的无锡市区土地利用变化情景模拟   总被引:5,自引:1,他引:4  
以城市化快速发展和生态环境压力突出的无锡市区为研究区,综合集成地形图、交通图以及1980、1995和2000年TM/ETM土地利用遥感解译资料,应用SLEUTH元胞自动机模型对土地利用变化过程进行情景模拟,揭示不同土地保护强度下的土地利用变化趋势。研究结果:SLEUTH模型首先对过去土地利用变化实现了动态模拟,模拟精度较高;在模拟形成的未来土地利用变化情景中,情景Ⅰ是基于维持现状土地利用保护强度基本不变的假设,城镇用地将迅速扩张,并占用大量水田和旱地,城镇扩张形态以边缘增长为主;情景Ⅱ则将水田保护强度提高50%,旱地提高12%,林草地提高50%,则城镇用地迅速扩张及耕地大量被占用的趋势得到有效控制;研究也进一步证明了SLEUTH模型在我国快速城市化背景下土地利用变化模拟和预测中的适用性。  相似文献   

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