Impacts of Human Water Use on the Large-scale Terrestrial Water Cycle

Along with the increase of population and extraordinary economic and social development, human appropriation of freshwater supply increases rapidly. Anthropogenic activities have become an important driving factor of the large-scale terrestrial water cycle. The hydrological effects of human water use have attracted growing attention. In this paper, we briefly reviewed the recent studies addressing the anthropogenic disturbance of the large-scale terrestrial water cycle. The review focused on the direct alteration of the water cycle for human needs, with special coverage for the primary aspects of human water use such as irrigation, domestic and industrial water use, reservoir regulation and groundwater mining. The state-of-the-art parameterization schemes of human water use for macroscale land surface hydrological modeling were introduced and the limitations of the schemes were discussed. Considering the impacts of human water use on the terrestrial water cycle is currently a challenge for macroscale land surface hydrological modeling, which hinders the use of the models in assessing water resources under changing environment. Further studies are needed to understand the interactions between human and water systems, to develop integrated assessment model of coupled human-water systems, and to assess regional and global water security.     

大型灌区陆地水循环模式的参数化方案:LWCMPS_ID

地表水系统、地下水系统和土壤植物大气连续体的强烈耦合作用是大型灌区水文过程的基本特点,这导致对大型灌区的陆地水循环和水资源进行评价必须采取综合的方法,然而目前还缺少适用的模拟工具。农业灌区的水文特征与天然流域存在显著差别,常规流域水文模型和陆面过程参数化方案用于大型灌区陆地水循环的分析还存在较大的困难。LWCMPS_ID是本文提出的一个适用于大型灌区陆地水循环模式的参数化方案,采用分块集中参数模型简明地实现了地表水、地下水和土壤水的动力学耦合分析,并且包含了一个土壤水冻结融化的简化模型。对处在黄河流域的内蒙古河套灌区,用LWCMPS_ID进行20 年水文动态的模拟,取得了较好的效果。     

干旱区内陆河流域生态水文综合集成研究

针对干旱区内陆河流域生态环境问题,面对国家重大需求及地球系统科学发展方向,指出内陆河流域生态水文综合集成研究的必要性,旨在为精细管理水资源,提高单方水产出效益（经济效益和生态效益）提供思路。以黑河流域为例,追踪流域研究历程,目前从野外调查试验观测,模型模拟到研究平台建设,黑河流域的数据知识的积累已基本具备开展流域生态水文综合集成的条件,但仍然存在着巨大的挑战。根据存在的问题,提出未来进行集成研究应加强的3个方面：①加强综合观测;②强调人文因素的定量研究和人文过程的研究;③重视模型、模拟方法在描述和反演地理真实中的应用。     

青藏高原水文模拟的现状及未来

介绍了青藏高原水文模拟的研究现状和发展趋势。水文模拟是研究水文过程的主要手段,可为流域水资源管理及防灾减灾提供理论和决策支持。国际上第一代水文模型为"集总式",第二代水文模型为"分布式",但它们大都以描述降水—产流的水分输移为主("水圈"),未仔细考虑陆—气水热交换中植被的调节作用("生物圈—大气圈")。近10年来,在气候变化的背景下,随着大气科学以及生态学的蓬勃发展,分布式水文模型开始描述生物圈—大气圈相互作用;通过改进陆—气间的水热交换过程以及植被的生理过程,实现了对流域水圈—生物圈—大气圈的综合模拟。然而,针对显著受冰冻圈过程影响的青藏高原,需要深入研究冰冻圈与其他圈层(水圈/生物圈/大气圈)的相互作用机理,并实现其在水文模拟中的参数化,以提升区域水资源和水灾害的预测能力。     

数字黑河的思考与实践3:模型集成

介绍了"数字黑河"模型集成研究的进展.①流域科学研究中的模型集成由发展流域集成模型和建模环境这2个主题所构成,前者可概括为"水-土-气-生-人"集成模型,后者是支持集成模型的高效开发的软件工具,注重于应用先进的信息技术为建模提供支撑.②将模型集成分为知识途径和技术途径,讨论了建模环境在模型集成中的作用,以及科学模型和流域管理模型的关系.③回顾了黑河流域模型集成的总体目标是发展两种类型的集成模型,其中第一种回应科学目标,是地球系统模型在流域尺度上的具体体现,以建成能够综合反映流域水文-生态-经济相互作用的模型为标志;第二种集成模型回应管理目标,以建成空间显式的流域水资源决策支持系统为目标.④对黑河流域已有的水文、地下水、水资源、陆面过程、土地利用、生态、社会经济与生态经济建模工作做了系统的综述.⑤分析了黑河流域集成模型研究中存在的问题和所面临的挑战.     

基于计算流体力学的寒区土壤水热耦合模型研究

土壤水文过程（水分运移和传热）及其对气候变化的响应是寒区水文学的前沿问题。然而,冻土的存在使得寒区土壤水文过程变得极其复杂。此外,寒区自然环境恶劣,较难获取长时间序列和高分辨率的野外观测资料。近年来,充分利用已有的观测数据,构建寒区土壤水热耦合模型,并开展相应的数值模拟研究,已成为理解寒区土壤水文物理过程,揭示其动力学机制的重要途径。基于寒区土壤水文物理过程和计算流体力学方法,构建了高分辨率、适用于完全饱和状态下的寒区土壤水热耦合模型,且自主研发了相应的数值求解器和软件包。随后,通过一系列完全饱和状态下的验证算例,如经典的一维传热方程解析解、被广泛应用的二维基准测试算例和室内土柱冻结实验等,对已构建的模型进行了系统的检验。模型模拟结果与解析解、基准算例的结果以及实验数据相比,均有较好的一致性,表明该模型较为准确且高效地模拟了寒区土壤在完全饱和状态下的水分运移和传热过程,尤其能够精细刻画冻土水-冰相态变化等关键过程,有望成为研究寒区土壤水文过程的有力工具。     

祁连山黑河干流山区水文模拟研究进展

流域水文模拟是在认识水文规律的基础上, 对流域水文过程的一种数学描述.黑河流域作为典型的内陆河流域历来是研究寒区、 旱区水文过程的热点区域.祁连山黑河干流山区的水文模拟研究也备受学者们的关注, 经验模型、 概念模型和分布式水文模型在该区域均有应用, 虽然都对出山径流做出了准确的模拟, 但是引进的模型对高寒山区水文过程的刻画不够详细.内陆河高寒山区流域的水文模拟要充分考虑冰川、 积雪、 冻土等因素所引起的特殊寒区水文过程, 准确刻画这些水文过程是高寒山区流域水文模拟成功的关键.今后应该继续加强野外观测, 深入开展冻土水文过程、 冰雪水文过程的模拟研究, 发展真正适合于高寒山区流域水文过程的分布式水文模型.     

Integrated Water Systems Model for Terrestrial Water Cycle Simulation

The terrestrial water cycle is influenced by a wide range of climatic variables and human disturbances. In the era of the Anthropocene, when humans drive the changes in atmospheric and hydrological processes in river basins, there is an urgent need to include human impacts in the study of the terrestrial water cycle. This paper focused on the large-scale hydrological modeling which takes account of human impacts, reviewed the research progress of the natural and human-induced changes in the terrestrial water cycle and the development of comprehensive terrestrial hydrological models in recent years, and proposed that an integrated water system model with human-related processes such as crop water demand model, engineering regulation and social water demand, be the key to large-scale water cycle simulations under changing environment. Based on the existing large-scale land surface hydrological model, there is a need to put forward the integration of the human-related processes. A comprehensive integrated water system model that considers multi-processes can help us to understand the key mechanisms of how climate change and human activity influence the regional water cycle. It also provides a theoretical and practical basis for investigating the causes and effects of changes in terrestrial water cycle under a changing environment, and thus offers scientific support for climate change adaptation in the water sector.     

Integrative assessment of hydrological, ecological, and economic systems for water resources management at river basin scale

This study presents a basin-scale integrative hydrological, ecological, and economic (HEE) modeling system, aimed at evaluating the impact of resources management, especially agricultural water resources management, on the sustainability of regional water resources. The hydrological model in the modeling system was adapted from SWAT, the Soil and Water Assessment Tool, to simulate the water balance in terms of soil moisture, evapotranspiration, and streamflow. An ecological model was integrated into the hydrological model to compute the ecosystem production of biomass production and yield for different land use types. The economic model estimated the monetary values of crop production and water productivity over irrigated areas. The modeling system was primarily integrated and run on a Windows platform and was able to produce simulation results at daily time steps with a spatial resolution of hydrological response unit (HRU). The modeling system was then calibrated over the period from 1983 to 1991 for the upper and middle parts of the Yellow River basin, China. Calibration results showed that the efficiencies of the modeling system in simulating monthly streamflow over 5 hydrological stations were from 0.54 to 0.68 with an average of 0.64, indicating an acceptable calibration. Preliminary simulation results from 1986 to 1995 revealed that water use in the study region has largely reduced the streamflow in many parts of the area except for that in the riverhead. Spatial distribution of biomass production, and crop yield showed a strong impact of irrigation on agricultural production. Water productivity over irrigated cropland ranged from 1 to 1640 USD/(ha·mm⁻¹), indicating a wide variation of the production conditions within the study region and a great potential in promoting water use efficiency in low water productivity areas. Generally, simulation results from this study indicated that the modeling system was capable of tracking the temporal and spatial variability of pertinent water balance variables, ecosystem dynamics, and regional economy, and provided a useful simulation tool in evaluating long-term water resources management strategies in a basin scale.     

陆地水循环过程的综合集成与模拟

在气候变化与人类活动的影响下,陆地水循环过程发生了明显改变,并导致了一系列资源环境问题。深入认识陆地水循环过程的变化机理,发展陆地水循环过程综合集成模拟技术,预估未来陆地水循环的变化趋势,是当前水循环研究面临的重要任务。主要关注人类活动影响下的大尺度(大河流域或大陆尺度)陆地表层系统水循环模拟,梳理了近年来陆地水循环过程综合集成与模拟相关的研究进展,指出当前大尺度陆地表层系统水循环模拟模型的主要问题是对自然过程与人类活动过程间相互作用描述不足,以及人类活动参数化方案的不完善。因此,完善人类活动参数化方案,构建陆地水循环过程的综合集成模型,是模拟研究的重要发展方向之一。同时,考虑多要素过程的综合集成模型有助于解释气候变化与人类用水活动影响水循环变化的关键机制,为探索变化环境下陆地水循环变化成因及其效应提供理论与实践基础,其结果将为区域水资源配置及应对全球变化的战略决策提供科学依据。     

内陆河流域山区水文与生态研究

以河西走廊黑河干流山区流域为例,从山区水文循环、水文与生态系统以及径流形成和预测等方面讨论山区流域水文和生态相互作用研究的有关问题。山区降水的空间和时间分布规律和固态、液态降水组成变化主要受制于海拔和地形的影响,而不同海拔和地形条件下的下垫面不同土地覆被和复杂的空间异质性则主要影响蒸散发量。对内陆河山区流域的水文小循环的研究,有助于进一步研究和认识内陆河流域上、中、下游水文和生态系统的相互联系问题。至今,对山区水文过程与生态系统的相互作用问题的研究还非常薄弱,需要研究山区森林草地生态系统在山区水文循环中的作用以及在维持和保护山区生态和环境中的作用和意义。内陆河流域山区水文过程复杂而综合性强,须加强对山区径流形成机理的多学科交叉研究,不断改善出山径流对气候变化和人类活动响应过程的模拟和预测水平。     

变化环境下城市水文学的发展与挑战——I.城市水文效应

全球气候变化和快速城市化导致的城市水循环过程变化是当前城市水文学研究的热点问题。为综合理解城市水循环演变过程,结合城市水文学的发展历程,剖析水循环过程对快速城市化进程的响应机制。总结了国内外城市化水文效应的主要成果,包括城市化对水循环过程、洪涝灾害、水生态系统以及水资源的影响。系统归纳了城市化水文效应的评估方法和技术手段。针对现有研究中的不足,指出变化环境下城市化水文效应研究面临的主要挑战及关键技术难题,提出未来研究的重点方向,如城市化降水效应的机理、不透水面的分布及有效性评估、城市化与水生态系统的响应关系与综合城市水资源管理及需水预测等。     

Models of natural and human dynamics in forest landscapes: Cross-site and cross-cultural synthesis

We synthesize the study of coupled natural and human systems across sites and cultures through a process of simplification and abstraction based on multiple dimensions of human-nature connectedness: satisfaction of basic needs, psycho-cultural connectedness and regulation of use of natural resources. We thus provide both a place-based and general understanding of value-driven anthropogenic environmental change and response. Two questions guide this research: what are the crucial stakeholder values that drive land use decisions and thus land cover change? And how can knowledge of these values be used to make decisions and policies that sustain both the human and natural systems in a place? To explore these questions we build simulation models of four study sites, two in the State of Texas, United States, and two in Venezuela. All include protected areas, though they differ in the specifics of vegetation and land use. In the Texas sites, relatively affluent individuals are legally converting forests to residential, commercial, and industrial uses, while in Venezuela landless settlers are extra-legally converting forests for purposes of subsistence agriculture. Contemporary modeling techniques now facilitate simulations of stakeholder and ecosystem dynamics revealing emergent patterns. Such coupled human and natural systems are currently recognized as a form of biocomplexity. Our modeling framework is flexible enough to allow adaptation to each of the study sites, capturing the essential features of the respective natural and anthropogenic land use changes and stakeholder reactions. The interactions between human stakeholders are simulated using multi-agent models that act on forest landscape models, and receive feedback of the effects of these actions on ecological habitats and hydrological response. The multi-agent models employ a formal logic-based method for the Venezuelan sites and a decision analysis approach using multi-attribute utility functions for the Texas sites, differing more in style and emphasis than in substance. Our natural-systems models are generic and can be tailored according to site-specific conditions. Similar models of tree growth and patch transitions are used for all the study sites and the differing responses to environmental variables are specified for each local species and terrain conditions.     

黑河流域节水生态农业与流域水资源集成管理研究领域

概述了中国内陆河流域面临的水问题和日益激化的用水矛盾,强调了内陆河地区支柱产业——绿洲农业应该坚持节水和生态的方向,流域集成管理是持续农业的基础。长期从事该方面研究的黑河流域是个较好借鉴,同时也提供了深入开展相关研究的基础,为此提出了以黑河流域为背景的四大研究流域：水文、生物、经济系统水循环与水资源形成演变,节水农业的生物学研究与抗旱品种繁育,农业节水新材料研发与工程节水技术集成,水资源合理配置与流域集成管理;并简述了各领域的主要方向。     

Environmental fragility framework for water supply systems: a case study in the Paulista Macro Metropolis area (SE Brazil)

Water resources availability is increasingly constrained, considering the quality and quantity available for use. There is an urgent need of recovering this availability, focusing on the planning and management process of water supply systems. One of the main threats to water resources is related to erosion effects, namely widespread pollution load and the silting of watercourses and reservoirs useful life reduction. The objective of this study was to evaluate water supply systems environmental fragility within the Paulista Macro Metropolis area and to use the results to develop environmental zone classes to orient territorial planning. The study was conducted in seven superficial water supply systems of the aforementioned region. Environmental fragility evaluation was focused on four environmental variables that represent natural vulnerability to erosion, and 2015 land cover map to delineate human influence on erosive processes. Results indicate that Tietê River water supply systems, namely Piracicaba, Capivari and Jundiaí (PCJ) and Itupararanga systems, can be considered the most fragile water supply systems in the study area. The environmental fragility map was used to derive the environmental zoning map, including conservation and priority areas, suitable regions for agriculture expansion, and areas with high needs for restoration efforts. In addition, environmental fragility framework herein can be viewed as a model with high replication potential for regional planning and management in that land cover can be manipulated to minimize environment natural vulnerability, guiding territorial occupation toward a more sustainable landscape design, which subsidizes water resources multiple uses.     

水文模型在估算冰川径流研究中的应用现状

冰川径流估算是气候变化风险评估和水资源可持续管理的重要内容.冰川径流估算方法主要包括:直接观测法、冰川物质平衡法、水量平衡方程法、水化学示踪法和水文模型法.本文首先对五种方法的应用情况进行简要总结,进而重点阐述水文模型法在估算冰川径流研究中的应用现状.水文模型法是冰川径流估算研究中使用最频繁的方法,使用方式主要包括耦合冰川模块和开发新的冰川水文模型.冰川水文模型中的消融算法主要包括温度指数模型(度日因子法)、修正的温度指数模型、能量平衡模型.受当前观测条件限制,修正的温度指数模型兼顾能量平衡模型和温度指数模型的优势而成为冰川水文模型中最流行的方法.随着学科的发展进步,能量平衡模型与水文模型的耦合将会成为未来的研究重点,发展大尺度分布式冰川水文模型是冰川水文学的未来发展方向之一.     

可持续水资源系统管理研究与展望

依据近些年国际水文水资源学术会议及交流等信息,综述近年来社会可持续发展对水资源系统管理提出的新的挑战及国际上可持续水资源系统管理研究的若干特点等问题,提出了几点认识和建议。     

Basin-scale groundwater response to precipitation variation and anthropogenic pumping in Chih-Ben watershed, Taiwan

The sustainable use of groundwater has become increasingly challenging due to extreme hydrological events and anthropogenic activity. In this study, the basin-scale groundwater response to precipitation variation was analyzed using an integrated model that comprises lumped models for land and river recharges and a distributed model for groundwater. The integrated model was applied to the Chih-Ben watershed, Taiwan, using 20?years (1988?C2007) of data. The hydrological data were analyzed for trends using statistical tests. Based on decreasing trends in precipitation and groundwater levels and an increasing trend in stream flow, the oblique-cut method was applied to precipitation and excess infiltration to assess land and streambed recharge. Distributed numerical groundwater modeling was used to simulate the basin-scale groundwater responses to precipitation variation and anthropogenic pumping. The model was calibrated using stable-isotope and groundwater-level data. The safe yields were estimated for the Chih-Ben watershed for dry, wet, and normal precipitation scenarios. The safe yield of groundwater was shown to vary with precipitation, which does not guarantee the sustainable use of groundwater resources. Instead, water resources should be assessed at a basin scale, taking into account the whole ecosystem, rather than only considering water for human consumption in the alluvium.     

内陆河高寒山区流域分布式水热耦合模型（Ⅰ）：模型原理

在全球变暖的背景下，我国多数大江大河源区存在冰川退缩、雪线上升以及多年冻土和季节冻土明显退化等现象，并由此造成河源区产流量减少以及生态环境恶化等诸多问题，这在内陆河山区流域体现的较为明显，但目前分布式水文模型中很少涉及冻土水热耦合问题。文章以黑河干流山区流域为例，构建了一个内陆河高寒山区流域分布式水热耦合模型（DWHC）。模型基于土壤水热连续性方程将流域产流、入渗和蒸散发过程融合起来，在植被截留、入渗、产流和蒸散发计算方面也有所改进和创新，部分模块具有多个可选择方案。模型设计了与中尺度大气模式MM5的嵌套接口，也可以用地面气象资料驱动。模型在1 km×1 km网格基础上，以日为时间步长，将流域土壤分为18类，土壤剖面分为3～5层不等，流域植被概化为9类。模型只需要土壤初始含水量、初始地温和常规气象资料，以及土壤和植被物理参数，就能够连续演算各层土壤的温度、液态含水量、固态含水量、感热传导、潜热变化、水势梯度、导水率以及水分入渗和毛细上升量等水文循环要素。主要介绍了模型的基本原理和构建思路，有关模型的地面资料驱动结果和与MM5嵌套结果部分，参见后续文章(Ⅱ)、(Ⅲ)。     

土地利用变化对水文系统的影响研究

以秦淮河流域为研究区域，利用现代遥感、地理信息系统等多种数字技术，获取流域空间分布的下垫面信息和中间状态信息，细致地刻画了流域内的水文过程，建立了研究区域数字水文模型。利用所建立的数字水文模型，对定义的土地利用变化情景进行了模拟。模拟结果表明，模型可以定性和定量地反映各种土地利用变化对水资源系统尤其是对水量平衡和防洪情势的影响程度。