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1.
Our world is changing at an unprecedented rate in terms of climate and land use, but these changes can affect our water resources. Hence, we need a methodology that can predict both their individual and agglomerative ramifications. Using the Little Miami River (LMR) watershed as a case study, this paper describes a spatial analytical approach integrating mathematical modeling and geographical information sciences to quantitatively examine the relative importance of the separate and combined hydrologic and water quality impacts of climate and land use changes.The Hydrologic Simulation Program - Fortran (HSPF) model was chosen in this study to simulate stream flow and nutrient transport process. Five hypothetical climate change scenarios were used to cover the possible ranges of variability in the year 2050. An enhanced population-coupled Markov-Cellular Automata (CA-Markov) land use model was developed to predict the 2050 land use pattern. When these scenarios were incorporated into the HSPF model, the future conditions in the LMR basin were postulated. The findings demonstrated that: 1) the LMR watershed would experience an increase in flow and nutrients under the 2050 land use projection, 2) stream flow and water quality impacts would be amplified when both climate and land use changes were simultaneously considered, 3) land use change (and in the case of the LMR watershed, urbanization) could help to alleviate water shortage during the dry years, 4) total phosphorus and nitrogen would increase under all future climate and land use scenarios; the highest increase was found under the combined wettest and future land use scenarios, and 5) the described approach is effective in simulating the hydrologic and water quality effects of climate and land use changes in a basin scale. These results are relevant to planners; they can be useful in formulating realistic watershed management policies and mitigation measures.  相似文献   

2.
黄土丘陵区燕沟流域土地利用变化与优化调控   总被引：47，自引：2，他引：47  
徐勇  Roy C.Sidle 《地理学报》2001,56(6):657-666
采用GIS空间分析技术，分析和概括了1966－2000年期间燕沟流域土地利用变化时空过程及其基本特征：解析了土地利用变化的主要成因；总结了1997年以来土地利用结构优化调控的主要特点；评价了土地利用结构优化调控后的生态环境效益、经济效益及其可持续发展性。籍此希望揭示出黄土丘陵区土地利用变化与优化调控所具有的一些共性特点和规律。  相似文献   

3.
流域土地利用/覆被变化对洪河保护区湿地景观的影响   总被引：16，自引：0，他引：16  
刘红玉  李兆富 《地理学报》2007,62(11):1215-1222
从流域尺度, 应用遥感和GIS 技术对1954 年以来6 个时段土地利用/ 覆被变化进行分析, 并采用景观生态学方法对洪河保护区及其所在浓江河流域湿地景观多样性和景观连通度进行计算, 系统研究了流域土地利用变化对保护区湿地景观的影响。结果显示: ① 浓江河流域大规模土地利用发生在20 世纪80 年代之后, 年均耕地面积增长速度为101 km2/a; ② 土地利用/ 覆被变化直接导致流域湿地景观多样性降低, 同时也间接影响了洪河保护区湿地景观多样性; ③ 流域土地利用变化带来的景观连通度降低严重割断了景观之间原有的物质交换和功能维持关系, 是导致保护区湿地景观结构和功能改变的主要因素之一; ④ 恢复保护区周围一定面积的湿地, 维持良好的景观连通度是实现保护区自然保护效益的方法之一。  相似文献   

4.
范泽孟 《地理学报》2022,77(1):228-244
如何实现自然与人文双重驱动下的特大城市群地区土地覆被变化的情景模拟,不仅是当前土地覆被变化研究领域的热点问题,也是城镇化可持续发展研究的核心主题之一。本文在对现有土地覆被变化情景模型缺陷进行分析和修正的基础上,构建了自然要素与人文要素耦合驱动的土地覆被情景曲面建模（SSMLC）方法。结合IPCC 2020年发布的共享社会经济路径（SSPs）与典型浓度路径（RCPs）组合的CMIP6 SSP1-2.6、SSP2-4.5和SSP5-8.5的气候情景数据,以及人口、GDP、交通、政策等人文参数,分别实现了SSP1-2.6、SSP2-4.5和SSP5-8.5情景下的京津冀土地覆被变化的情景模拟。模拟结果表明：SSMLC对京津冀地区土地覆被变化模拟的总体精度为93.52%;京津冀地区的土地覆被在2020—2040时段内的变化强度最高（3.12%/10a）,2040年以后的变化强度将逐渐减缓;在2020—2100年间,建设用地增加速度最快,增加率为5.07%/10a。湿地的减少速度最快,减少率为3.10%/10a。2020—2100时段内的京津冀土地覆被在SSP5-8.5情景下的变化强度整体高于在SSP1-2.6和SSP2-4.5情景下的变化强度;GDP、人口、交通和政策等人文因子对京津冀地区耕地、建设用地、湿地和水体的影响强度高于对其他土地覆被类型的影响强度。研究结果证实了SSMLC模型能够有效模拟和定量刻画京津冀地区土地覆被空间分布格局在未来不同情景的时空变化趋势和强度,模拟结果可为京津冀协同一体化的国土空间优化配置与规划、以及生态环境建设提供辅助依据和数据支撑。  相似文献   

5.
Land use conversion typically implicates deforestation and fragmentation of primary land cover types, which invariably translates into impoverishment of both natural and cultural capital. Understanding where conversion is taking place crucially underpins sound environmental policy instruments to prevent these enormous social and economic costs. This paper examines 30 years of semi‐detailed (1:250 000) land cover mapping in Mexico. Pre‐existing analogue databases describing land cover patterns in the 1970s and 1990s were reviewed, corrected, reorganized and transformed into a digital format. Current land cover patterns were depicted by conducting updated reinterpretation on Landsat ETM+ imagery. Digital cartographic overlaying was performed and the results were used to construct a spatially explicit land use/land cover change (LULCC) database with an additional accuracy assessment procedure. The value of the results of this analysis is also seen in the light of their direct applications for identifying critical watershed trends, for guiding the allocation of financial funds for sound land use planning and for assessing the effectiveness of established protected areas. This effort highlights the importance of new and more effective geographical approaches to depict, understand and contribute to informed measures to mitigate ongoing negative trends in land cover and climatic changes.  相似文献   

6.
Mountaintop removal mining is a dominant driver of land use/land cover changes in the Appalachian Region of the eastern United States and is expected to increase in scale in the coming decades. While several studies quantify land use/land cover changes attributed to traditional surface mining and at regional scales, no studies we are aware of focus specifically on mountaintop removal/valley fill mining practices at the watershed scale. Further, despite its scale and extent, its impact on runoff, particularly at larger spatial scales (103 km2), is poorly understood due to the complex relationships between climate, land use, and hydrology. To explore the impacts of this practice at broader scales, we estimated land use/land cover changes using Landsat 5 TM imagery over five periods between 1994 and 2010; used a simple rainfall–runoff model to estimate hydrologic response time; and conducted non-parametric trend analyses on annual hydrologic metrics (streamflow, Q/P, response time) for the Big Coal River watershed located in the southern West Virginia coalfields. No statistically significant trends were detected in any of the timeseries. The lack of detectable trends and correlations between land use changes and hydrology at the basin scale are not entirely unexpected due to the history and mosaic of land cover changes that span timescales larger than our study period. Further interannual variation likely overwhelms our ability to detect potential changes using monotonic trend analysis at the annual time scale, particularly in light of strong streamflow seasonality. Future studies therefore should include different methods of change detection applied to different timescales to more appropriately account seasonal and interannual variations. Until the significance of this practice on water resources (quality and quality) are understood, efforts to reduce the environmental problems associated with mountaintop mining will be difficult to achieve.  相似文献   

7.
多尺度土地利用与土壤侵蚀   总被引：20，自引：5，他引：15  
土地利用能够通过改变一系列的自然现象和生态过程影响土壤侵蚀,尺度不同,土地利用与土壤侵蚀的作用机制也会发生变化。本文针对坡面尺度、小流域／流域尺度和区域尺度,综述了不同尺度上土地利用对土壤侵蚀的影响研究。其中,在坡面尺度上,土地利用与土壤侵蚀的研究主要包括土地利用方式和土地管理措施对土壤侵蚀的影响,相应尺度上的模型有USLE／RUSLE、WEPP等;在小流域／流域尺度上,土地利用与土壤侵蚀的研究主要涉及土地利用结构和土地利用格局对土壤侵蚀的影响,相关的模型有LISEM、AGNPS、EUROSEM和SEDEM等;在区域尺度上土壤侵蚀评价研究主要是通过尺度上推和宏观因子评价的方法进行。多尺度土地利用与土壤侵蚀研究作为自然地理学研究中的热点问题,在进一步的研究中需要关注多尺度综合与尺度转换、土地利用政策效应、土地利用格局与土壤流失过程等方面的研究内容。  相似文献   

8.
流域LUCC水文效应研究中的若干问题探讨   总被引：21，自引：2，他引：21  
随着全球变化研究的深入,土地利用/覆被变化(LUCC)的水文效应研究日益成为热点问题。综合国内外研究进展,论文就流域土地利用/覆被变化水文效应研究中的几个问题进行了总结和探讨：子流域和水文响应单元是分布式水文模型对流域基本空间单元的理想划分;对国内外现有的土地利用分类系统进行了适当的调整和归并,建立了基于水文响应研究的土地利用分类系统,将土地利用分为9个Ⅰ级类和21个II级类;土地利用/覆被变化情景分析的常用方法有参照对比法、历史反演法、模型预测法、极端土地利用法、土地利用空间配置法等。  相似文献   

9.
流域土地利用/覆被变化水文效应研究的方法评述   总被引：3，自引：0，他引：3  
将流域土地利用/覆被变化(LUCC)水文效应研究的主要方法归结为3类:流域对比试验法、水文特征参数法和流域水文模型模拟法.流域对比试验法适用于较小流域,试验结果比较容易获得,但不易找到主要影响因子,对比性差,研究周期长;水文特征参数法是一种简洁的分析LUCC水文效应的方法,资料丰富更有助于提高其应用价值,但该法只能判断流域内的水文响应是否发生了变化,无法解释水文变化的机理;水文模型模拟法的种类较多,其中基于物理机制的分布式水文模型更适于研究人类活动造成的水文效应,其参数物理意义明确,且充分考虑了空间异质性,在模拟LUCC的水文效应方面,该方法具有较为明显的优势,特别是在计算机技术、3S技术日趋成熟及数据库建设不断完善的条件下,其优势更明显.针对现阶段国外比较常用的10种流域水文模型,分析了它们的结构及特点,旨在对流域LUCC的水文效应研究提供基础.  相似文献   

10.
利用1976、1989、2005年三期遥感影像,运用GIS和分形理论研究干旱区典型流域——玛纳斯河流域近30年的土地利用/土地覆被变化的复杂性和稳定性。结果表明:玛纳斯河流域各时段的土地利用/土地覆被类型分布具有分形结构,土地利用/土地覆被类型形状复杂性和斑块的稳定性波动变化,1976、1989、2005年三时期的各种土地利用/土地覆被类型总平均分维值分别为1.394 0、1.363 4和1.389 9。总平均稳定性指数分别为0.606 0、0.636 6、0.610 1。三期土地利用/覆被类型平均稳定性排序为:沙地>未利用土地>居民点工矿用地>水域>林地>草地>耕地>盐碱地。耕地、林地、草地、盐碱地稳定性相对较差。通过对流域土地利用/土地覆被类型变化复杂性和稳定性的研究,可以为政府协调水土开发和调整土地利用结构提供支持。  相似文献   

11.
Combined with recent historical climate data and two periods of land use data sets from remote sensing data, we test the net primary productivity (NPP) data sets in North China modelled by the satellite data-driven Global Production Efficiency Model (GLO-PEM) for detecting the widespread spatial and temporal characteristics of the impacts of climate and land use change on the regional NPP. Our results show that over the past 20 years, the mean annual temperature in the study region has remarkably increased by more than 0.064 oC, but over the same period, there has been a 1.49 mm decrease in annual precipitation and decrease in NPP by an annual rate of 6.9 TgC. The NPP changes in the study region were greatly affected by the average temperature and precipitation by ten-day periods as well as the seasonal temperature and precipitation in the study region. The correlation between seasonal NPP and seasonal precipitation and temperature is highly consistent with land cover spatially, and the correlation coefficient changes with the changes of vegetation types. The analysis reveals that the related areas in land use change only take up 5.45% of the whole studied region, so the climate changes dominate the impacts on the NPP in the whole study region (90% of the total). However, land use plays an absolute dominative role in areas with land cover changes, accounting for 97% of the total. From 1981 to 2000, the NPP in the whole study region remarkably reduced due to obvious precipitation decrease and temperature rise. Between two periods of land use (about 10 years), the changes in climate are predicted to promote a decrease in NPP by 78 (±0.6) TgC, and integrated impacts of climate changes and land use to promote a decrease in NPP by 87(±0.8) TgC.  相似文献   

12.
Deforestation and forest degradation are proceeding rapidly in the lowland forests of Indonesian Borneo. Time series analysis of satellite imagery provides an ideal means of quantifying landscape change and identifying the pathways which lead to the changes. This study investigates the forest and land cover changes by classifying Landsat MSS (Multispectral Scanner), TM (Thematic Mapper) and ETM+ (Enhanced Thematic Mapper Plus) images over three time periods (1983–90, 1990–98, and 1998–2000), creating land cover maps for each year and change trajectories for each year-pair. The study area chosen covers an area of 2160 km2 of undulating topography and alluvial plains in the East Kutai District of East Kalimantan Province, which in the 1980s was covered mostly with lowland dipterocarp forest; today the landscape is a patchwork dominated by oil palm and timber plantations and degraded forest. We relate land cover change data to land use allocation and to fire impacts based on fire hotspot distribution and fire damage information. The multidate land cover change trajectories provide an insight into the forest loss and degradation pathways over the 17-year period spanning the first entry of commercial logging concessionaires, followed by a government-sponsored transmigration scheme, government-licensed timber and oil palm plantations and, finally, the devastating fires of 1998. The results show a mean deforestation rate of 42 km2 or 6 per cent per year for 1983–2000, rising to 10 per cent per year for 1990–98; by 2000, 70 per cent of forest initially damaged by fire and drought during the 1982–83 El Niño event was classified as non-forest. Although our study area is perhaps a worst-case scenario in terms of land use planning outcomes, the lessons from this research are directly applicable to scenario prediction for informed forest and land use planning and monitoring.  相似文献   

13.
土地利用和气候变化对区域净初级生产力影响   总被引：4，自引：2，他引：2  
1IntroductionThe global change caused by the continuous increasing concentration of atmospheric greenhouse gases has threatened the existence of human beings, and the importance of carbon dioxide emissions as a major environmental issue of international concern has grown substantially in the world (IPCC, 2000). At the same time, the Kyoto Protocol, the first and only realistic plan for achieving a worldwide reduction in greenhouse gas emissions, has been passed. Since there are many uncertai…  相似文献   

14.
The objective of study was to explore short-term trends of processes that determine land-use change in Sierra Norte of Oaxaca (SNO), Mexico. Land use and land cover changes (LULCC) were estimated in a complex mosaic of vegetation in the SNO from 1980 to 2000, and projected them to 2020 through a Markovian model. SNO is highly vulnerable to climatic change according to a 2050 GCM scenario. However, 3% annual rate of tropical and temperate forest deforestation from agriculture and livestock encroachment, suggest the threat from land-use change is higher than that from climatic change for this study site. Productive land-use strategies are needed to reduce such high deforestation rates for tropical regions. Controlling deforestation would also reduce short-term effects of CO2 emissions to the atmosphere. Because of the necessity to evaluate anthropogenic ecosystem changes, it is imperative to separate short-term influences such as deforestation, from long-term influences such as climatic change.  相似文献   

15.
bnP0ItaIlce0fShIdyolILaIldUsealldLalldC0veI'CIlangef0l'GI0balCIlallgeResealtIlSttldyollland[Iseandlandcoverc1lange(LULCC)isOI1eoftnein1portantareasforullderstandingregionala11dgl0balellvironllleIltalconseqLIences.A1tno[lglllandcoversocQlPyonlyone-thirdoftneeartn'ss[lrface,tneland[lsePatter11andn[ln1analternations0flandcoverllavein1pofta11tin1Pacto11gl0bal-scalecnangnoftneclin1ate,bi0gnocnen1istry,nydrology,andbiodiversityofeaIthSystenl.TneI1eterognneityoftllelandsurfaceinterlnso…  相似文献   

16.
土地利用和气候变化对区域净初级生产力的影响   总被引：25，自引：1，他引：24  
应用以遥感观测数据驱动的GLO-PEM模式模拟估计的中国北方20年的NPP数据同其20年气候数据结合,同时利用通过遥感宏观调查所得的两期土地利用数据,分析20年气候和土地利用变化对区域净初级生产力 (Net Primary Productivity,NPP) 的影响的时空特征。分析结果表明,20年来研究区域年均温度显著增加 (年均增温0.064 oC),年降水量明显减少 (年降水减少率为1.49 mm/年),NPP以减少趋势为主 (年减少率6.9 TgC)。研究区域NPP的变化受旬 (月) 均温和旬 (月) 降水量和季节温度和季节降水的变化影响显著。季节NPP同季节降水和温度的相关性在空间上同植被覆盖表现出高度的一致性,其相关系数大小随着不同植被覆盖类型变化而变化。通过分析可见,就整个研究区来说,发生土地利用变化的区域仅占整个研究区域的5.45%, 气候对整个研究区域NPP的影响占主导地位 (占了总影响量的90%);土地利用发生区域土地利用的作用占了绝对地位,土地利用的影响占了约97%。整个研究区域近20年来因为降水明显减少,温度显著升高,导致NPP明显下降,在两期土地利用间隔时间段内 (约10年) 因气候影响NPP减少了78 (±0.6) TgC。因为土地利用的变化导致NPP减少9 (±0.2) TgC。气候和土地利用共同作用是研究区域的NPP减少87 (±0.8) TgC。  相似文献   

17.
 利用1976年、1989年、2005年三期遥感影像,运用GIS和FRAGSTATS景观分析软件对玛纳斯河流域近30 a的土地利用/覆被变化和景观破碎化进行了研究。结果表明：①玛纳斯河流域土地利用/覆被在过去30 a间发生了普遍的变化。耕地、建设用地不断增加,而草地、林地、水域、盐碱地不断减少。耕地主要是在草地上开垦出来的。②绿洲内部的耕地趋于集聚状态,破碎性降低,而绿洲边缘的耕地,破碎性增强。草地面积大减,破碎性增强,退化严重。沙地、水域破碎性也不断增强,林地、未利用土地的破碎化于1989年增强,2005年减缓。③驱动力分析表明,流域变化是自然和人类活动共同作用的结果,其中人口的快速增长、政策环境的变化和自然环境变化如干旱等是最主要的驱动因素。  相似文献   

18.
流域径流量对气候变化的敏感性分析是理解气候变化对流域水资源影响的重要手段。本文利用非更新式人工神经网络(ANN)模型,以年平均降雨、年最低气温和最高气温为输入参数,年平均径流量为输出变量,构建了三江平原挠力河流域的径流量预测ANN模型;并根据IPCC第四次报告的气候变化模式,设定了9种不同的气候变化情景,利用构建的ANN模型分析了流域径流量对气候变化的敏感性。结果表明:构建的人工神经网络模型能够较好的模拟径流量,可用于气候变化的敏感性分析;挠力河流域上游径流量对气候变化的敏感性要大于中游区域的,降水变化对径流量的影响大于气温对其产生的影响。  相似文献   

19.
山区土地利用/覆被变化对土壤侵蚀的影响   总被引：42，自引：6，他引：36  
本文以福建省山区为例,在对福建省水土保持实验站、建瓯市牛坑龙水土保持试验站长期观测、实验资料深入分析对比的基础之上,探讨了土地利用/土地覆被变化对土壤侵蚀的影响规律。分析结果表明,土地利用/土地覆被变化对径流的产生和土壤侵蚀有重要影响,植被的覆盖度的变化直接影响着径流系数和土壤侵蚀模数;植被的覆盖度和径流系数呈负线性关系,随着覆盖度的增加径流系数逐渐减小;植被覆盖度和土壤侵蚀模数为负指数关系,随着植被覆盖度的增大,土壤侵蚀模数急剧下降。  相似文献   

20.
藏北那曲地区草地和未利用土地动态变化及原因   总被引：1，自引：0，他引：1  
张佳华  郑凌云 《山地学报》2005,23(6):672-677
根据1990年和2000年2期那曲土地利用馒盖分类图,运用GIS的空间分析和数理统计功能,分析那曲地区草地退化和未利用土地的增加情况,并结合气象资料和人口资料分析这些变化的原因。结果表明：10a间,那曲地区未利用地增加;草地减少,突出表现为草地向未利用地转化。草地向林地和耕地转化,导致这种结果的主要原因是由于人类的社会经济活动造成的,人类社会经济活动引起这一地区土地利用变化的强度已经超过自然因子所能达到的强度,起到了绝对的主导作用。  相似文献   

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