Impact of Land Use Land Cover (LULC) Change on Surface Runoff in an Increasingly Urbanized Tropical Watershed

Water Resources Management - Upper-Brantas watershed in East Java, Indonesia, is a tropical watershed experiencing rapid landscape change, a phenomenon typical to developing countries. This study...     

基于LCM模型的黄河三角洲土地利用变化预测

为探讨黄河三角洲地区土地利用演变规律及驱动机制,以东营市为例,采用1989年、1999年和2009年遥感影像解译土地利用类型,结合土地利用变化影响因子分析,构建土地利用变化预测模型(LCM)。以1989—1999年土地利用变化为基础,采用LCM模型模拟2009年土地利用变化,Kappa系数为0.877,验证了LCM模型具有较强的预测能力和可靠性。在此基础上,预测2019年土地利用变化,结果显示耕地、草地、未利用土地将持续减少,建筑用地、水域面积将有所增加。     

基于马尔柯夫模型的沙厂水库流域土地利用变化分析

基于沙厂水库流域1990年、1995年、2005年的TM遥感资料和2000年SPORT遥感数据,在GIS技术支持下,建立了沙厂水库流域土地利用数据库;运用马尔柯夫模型,对研究区域内土地利用动态变化进行分析研究。通过对流域2005年的土地利用变化进行验证,对该流域2010年的土地利用情况进行预测。结果表明：①阔叶林、针叶林、灌木林和农田面积呈上升态势,混交林、其他土地和水域面积呈下降趋势;②3期土地利用流向基本一致,林地之间存在互动变化,其他土地,水域和农田向林地方向转移;③阔叶林、针叶林、灌木林、混交林和其他土地是本流域土地利用变化的主导类型和主要方向,整个演变趋势使林草面积显著增加,林地类型以阔叶林和针叶林为主。     

不同干密度下土水特征曲线模型参数确定简化方法

为避免获得土水特征曲线模型参数的复杂测试过程,提出了一种确定模型参数的简化方法。通过使用Gardner,Van Genuchten,Fredlund & Xing 3种模型对土水特征曲线数据拟合,发现3种模型相关系数除干密度为1.50,1.60,1.71 g/cm³时Gardner模型的决定系数R²为0.940,0.949,0.953,其他相关系数均超过了0.96,拟合效果较好。对Gardner模型和Van Genuchten模型中各参数进行分析,发现它们与干密度之间有良好的相关性,干密度和各模型参数之间成线性、二次函数和幂函数关系,并据此提出了由干密度确定模型参数的简化方法,具有一定的实用性,期望能为工程提供参考。     

SCS-CN模型中CN值的空间移用效果研究

SCS-CN模型因其曲线数CN值可以根据下垫面(土壤和植被)确定,近年来在分布式水文模拟和无/缺资料地区得到较为广泛的应用。美国土壤保持局提供的CN查算表在中国地区并不完全适用,如果直接采用,可能会带来较大的径流计算误差。选择资料数据较好的北京柏崖厂站作为假定的无实测径流资料的目标站,通过相似流域特性分析确定北山下站为参证站,利用参证站资料计算出CN值校正系数,并将该系数引用到目标站,利用校正前后的CN值分别模拟多场次洪水。结果表明,SCS-CN模型的参数CN值修正后,在空间上具备一定的外推能力;无论在确定性系数、径流总量精度和洪峰流量精度上,CN值修正后的洪水预报精度都要比修正前要高。     

基于Logistic的土地利用格局模拟案例研究

土地利用/覆盖变化是当前研究全球环境变化的重要内容,而区域土地利用格局模拟是其核心内容之一。以甘肃省高台县宣化镇为研究区,将土地利用类型分为耕地、林地、草地、城镇用地、农村居民点用地、未利用地、其他用地,运用Logistic回归方法,选择7个驱动因子,建立Logistic回归模型,模拟土地利用变化。结果表明:研究结果拟合度较好,定量地揭示了距渠系、道路和居民点的远近是该地区土地利用类型演变的主要因素,各土地利用类型呈集聚方向演化。     

Prioritizing Structural Management by Quantifying the Effect of Land Use and Land Cover on Watershed Runoff and Sediment Yield

Hydrological processes in a mixed land use watershed are significantly influenced by land use (LU) and land cover (LC). In order to quantify the effect of LU/LC, topography, and morphology, runoff and sediment yield of a small multivegetated watershed in a sub-humid subtropical region in India were simulated by the Soil and Water Assessment Tool (SWAT) model and were compared with measured values. The mixed land use watershed displayed a synchronized runoff response to monsoon rains. Measured runoff and sediment yield varied one sub-watershed to another and ranged, respectively, from 256.33 to 367.83 mm and from 0.27 to 11.65 t/ha for 734.90 mm of rainfall in 2000 and from 310.36 to 393.49 mm and from 0.84 to 10.71 t/ha for 765.50 mm of rainfall in 2001. The correlation coefficient between rainfall and runoff was 0.86, that between runoff and sediment yield was 0.56, and that between rainfall and sediment yield was 0.55. The sub-watersheds with relatively high forest cover (SWS1 and SWS2) showed significantly less runoff and sediment yield (310.36 mm and 0.84 t/ha), whereas a sub-watershed with more area under cultivation produced higher runoff (393.5 mm) and higher sediment yield (11.65 t/ha). Measured and model simulated estimates of runoff and sediment yield from different sub-watersheds were employed to prioritize control measures in the watershed comprising areas under cultivation, waste, fallow and eroded land, and forest and bushes. The average estimates of sediment yield from different sub-watersheds were used to prioritize the checkdam construction as an effective measure to control sediment transport to downstream water resources.     

黑龙江省水土保持耕作方法保水增产效应研究

通过对深松耕法、保水剂、地膜覆盖及增施有机肥4种耕作方法多年定位观测,结果表明:4种耕作方法明显优于传统耕作方法,土壤含水率高4%~10%,产量高3%~30%。是黑龙江省干旱地区可以选择的保墒蓄水增产耕作栽培形式。     

基于FLUS模型的流域土地利用变化预测及水文响应评估

模拟未来不同发展情景下流域土地利用变化,评估其对流域水文的影响,对流域的土地利用优化和水安全起着重要的指导作用.通过分析2000—2018年汨罗江流域土地利用变化趋势,基于流域土地利用变化特点,运用FLUS模型从不划定发展控制区域的基准情景和划定限制发展区域的限制情景2个方面出发,进行2035年汨罗江流域土地利用预测,...     

旱地农业高效用水技术的应用研究

旱地农业面积约占全国耕地面积的59％，对国民经济具有举足轻重的作用。旱地农业没有灌溉条件，必须在提高降水利用率上做文章。旱地农业高效用水技术主要包括：适水种植、选育抗旱节水高产品种、搞好农田基本建设、耕作保墒、化学调控节水和抗旱灌溉。     

Experimental Verification of the Effect of Slope and Land Use on SCS Runoff Curve Number

The present study investigates experimentally the effect of watershed (i.e. field plot of 22 m?×?5 m) slope on rainfall-generated runoff and, in turn, the runoff curve numbers (CN) resulting from field plots (with land use of maize and sugarcane on the soil falling in Hydrologic Soil Group C) located in Roorkee, (India). The results indicated that the plot of 5 % slope yielded the largest runoff and, in turn, CN compared to those due to the plots of 3 and 1 % grades, for the same rainfall, soil, and land use. The CN derived from the present study were quite close to the NEH-4 CN-values, indicating satisfactory match between the two. The use of slope adjusted CN-values in the standard CN method significantly (at 5 % level) improved the otherwise underestimated large runoff events, i.e. model efficiency E improved from 0.47 to 0.78, and R² from 0.71 to 0.83.     

黄淮海平原风沙化土地利用时空变化研究

利用3S技术,分析了黄淮海平原风沙化土地典型区内的内黄、滑县和延津三县1979—2009年夏季土地利用变化特征。结果表明:该区近30 a的土地利用类型变化显著,变化趋势为耕地、水域和未利用地面积持续减少;林地和建设用地面积不断增加。黄淮海平原以风沙化土地为主的未利用地的利用,对研究区各土地类型之间的平衡起至关重要的作用。研究区土地利用演变规律性较强,社会经济的发展对该区林地、建设用地和耕地变化影响明显。     

环境生态用水基本概念

在我国长期供用水制度中，形成工业、农业、生活传统的供用水制度，唯独环境生态用水没有列入我国的用水制度。环境生态用水是保障人民生活与健康质量的不断提高，维护国家生态安全、水生态安全、环境安全和社会可持续发展的必备用水。本文从环境生态用水的角度来界定国内外研究动态、用水设计及水资源供需中计算调节等，首次提出尽快建立我国的环境生态用水制度。     

Hydrological Response to Agricultural Land Use Heterogeneity Using Variable Infiltration Capacity Model

Hydrological responses corresponding to the agricultural land use alterations are critical for planning crop management strategies, water resources management, and environmental evaluations. However, accurate estimation and evaluation of these hydrological responses are restricted by the limited availability of detailed crop classification in land use and land cover. An innovative approach using state-of-the-art Variable Infiltration Capacity (VIC) model is utilized by setting up the crop-specific vegetation parameterization and analyse the effect of uniform and heterogeneous agricultural land use over the hydrological responses of the basin, in the Kangsabati River Basin (KRB). Thirteen year simulations (1998–2010) based on two different scenarios i.e., single-crop in agricultural land use (SC-ALU) and multi-crop in agricultural land use (MC-ALU) patterns are incorporated in the model and calibrated (1998–2006) and validated (2007–2010) for the streamflow at Reservoir and Mohanpur in the KRB. The results demonstrated that the VIC model improved the estimates of hydrological components, especially surface runoff and evapotranspiration (ET) at daily and monthly timescales corresponding to MC-ALU than SC-ALU (NSC?>?0.7). Grid-scale ET estimates are improved after incorporating heterogeneous agricultural land use (NSC?>?0.55 and R²?>?0.55) throughout the period of 1998–2010. This study improves our understanding on how the change in agricultural land use in the model settings alters the basin hydrological characteristics, and to provide model-based approaches for best management practices in irrigation scheduling, crop water requirement, and management strategies in the absence of flux towers, eddy covariance, and lysimeters in the basin.

     

EasyDHM模型参数识别研究

模型参数取值的准确与否直接影响模拟精度的高低,为了提高乌鲁木齐河流域流量模拟精度,根据LH-OAT分析法筛选出对流域流量模拟精度影响较大的参数,利用SCE-UA方法计算出这些参数的最优值,并用1990—2009年实测日资料进行了参数率定及模型验证。结果表明:1土壤田间持水率、河道长度修正系数、径流曲线系数、土壤深度占总土层厚度的比例对流量模拟的影响最为敏感;2模型在率定期和验证期的模拟值与实测值的日相对误差均低于5%,纳什效率系数均超过0.80,相关系数在0.90以上,表明EasyDHM模型在乌鲁木齐河流域流量模拟的精度较高且适应性良好。     

Hydrological Prediction in a Tropical Watershed Dominated by Oxisols Using a Distributed Hydrological Model

Hydrological models have been used in many places of the world in order to support practitioners with respect to watershed management actions. The goal of this research was to apply the Lavras Simulation of Hydrology (LASH model) to a Brazilian tropical watershed dominated by Oxisols, to estimate maximum, minimum and mean stream flows for both current land-use (“scenario 1”) and other regional trend land-use scenarios (“scenario 2”—pasture into eucalyptus; and “scenario 3”—eucalyptus into pasture). This model is a continuous, distributed and semi-conceptual model for simulation of different hydrological components on a daily basis. The model had a good performance with respect to the “scenario 1”, resulting in Nash-Sutcliffe coefficients equal to 0.81, 0.82 and 0.98 for minimum, maximum and mean discharges, respectively. When “scenario 2” was simulated, it was found that minimum, mean and maximum stream flows had their values reduced in average by 7.39 %, 13.84 % and 20.38 %, respectively. On the contrary, it was observed in “scenario 3” an increase in average by 0.23 %, 0.44 % and 1.19 % for minimum, mean and maximum stream flows, respectively. With respect to water yield, scenario 2 resulted in a mean reduction of 119 mm, whereas for scenario 3 the difference was not so pronounced in relation to the current land use. Results obtained in scenario 2 are troublesome since this watershed drains into an important regional Hydroelectric Power Plant Reservoir and this approach needs to be considered by the Minas Gerais State electric energy company for its planning strategies for the future.     

紫色土区土地利用类型与降水变化对水土流失的影响

以川中丘陵区鹤鸣观小流域及其3个试验小区2个试验阶段（1983-1986年,1989-2000年）为研究对象,分析了不同土地利用类型水土流失特征、径流侵蚀对降水变化的响应及小流域综合治理后的效益。结果表明:对于第一阶段,不同雨强下的径流深变化依次是荒地＞草地＞坡耕地;侵蚀模数的变化依次为坡耕地＞荒地＞草地。对于第二阶段,其径流深变化依次是梯地＞草地＞林地;侵蚀模数的变化依次为梯地＞草地＞林地。荒地、低覆盖草地、坡耕地径流量、侵蚀量与降水变量相关系数较高,土壤侵蚀主要受降水变化影响。林地、高覆盖草地、梯地径流量、侵蚀与降水变量的相关系数较小且没有显著性,可能是植被覆盖、土壤特性对减缓径流和侵蚀过程具有重要作用,说明土地利用/覆被变化具有明显分异的水土流失效应。由于水土保持综合治理的作用,1990-2004年小流域多年平均径流量比1985-1989年多年平均径流量减少30.67%,多年平均输沙量减少91.29%,多年平均含沙量减少76.05%。     

基于土地利用数据库重建的技术思路

以SPOT5卫星数据为信息采集源,利用GIS与遥感相结合的方法对黑龙江省某县原有的土地利用数据库进行更新.着重阐述了进行更新的方法步骤.在更新过程中,卫星数据和原有土地利用数据库两种数据能够充分发挥各自的优势,做到相互补充和印证.     

Testing a Dynamic Complex Hypothesis in the Analysis of Land Use Impact on Lake Water Quality

In this study, we proposed a dynamic complex hypothesis that the impact of land use on water quality could vary along the expansion of the buffer size, and there should be an effective buffer zone where the strongest linkage occurs between land use and water quality. The hypothesis was tested and supported by a case study carried out in four watersheds in Hanyang District, China. More specific, buffer analysis and regression model were applied for studying the impacts of land use type, area proportion of land use type, and spatial pattern of land use on water quality. We conclude that not only the proportion of land use but also the spatial pattern moderates the impact of land use on water quality. Our study indicates that the identification of the effective buffer zones can provide new information and ideas for planning and management. Moreover, this study could also partially help to explain the conflicting results on the impact of land use on water quality in buffer versus in catchments in the literatures.     

亚塑性模型晶粒间应变参数研究

亚塑性模型是近年来提出的一种新的岩土本构模型,该模型不合屈服准则和破坏准则等概念,仅用一个张量方程来描述土体的耗散特性、塑性流动及剪胀特性等.亚塑性模型存在一个缺点:在小应变时,应力与应变之间出现锯齿现象.为了消除此现象,Niemunis与Herle提出了晶粒间应变概念,从仿真结果可以看出,与晶粒间应变相关的参数对计算...