土壤水文属性及其对水文过程影响研究的进展、挑战与机遇

土壤水文属性对水文过程、能量过程、碳氮循环过程及各过程间相互作用有重要影响.首先简要回顾近30年来土壤水文属性的研究进展,包括土壤水文属性的监测分析、土壤水文属性对水文过程的影响机理,以及不同尺度土壤水文属性对水文过程的影响差异及联系.其次,论述土壤水文属性研究的挑战与机遇.最后介绍祁连山区土壤水文属性对水文过程的影响及多尺度特征研究.力求加深对土壤水文属性变异规律及其对水文过程影响机理的认知,发展土壤水文学和山区水文学,支持水资源科学管理和区域可持续发展.     

我国工程水文分析计算的新进展

通过对我国在工程水文分析计算的回顾,总结了近年来我国在洪水频率分析、洪水不确定性研究、人类活动及气候变化对径流的影响等方面的最新进展,提出了今后水文计算的研究方向。     

人类活动的水文效应及研究方法

一、人类活动的水文效应人类活动对水文情势的影响,从其影响途径可分为直接与间接两大类。直接影响是指人类活动使水文要素的量、质和时空分布直接发生变化,如修建水库、跨流域调水、农作物灌溉、城镇供水及污废水处理等,都直接使水资源系统不断发生变化;间接影响则指人类经济活动通过改变下垫面状况及局地气候,     

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。     

生态水文科学研究的现状与展望

生态水文科学研究是区域生态系统研究和区域水文科学研究的交叉领域 ,其核心内容是揭示不同环境条件下植物与水的相互关系机理 ,探索各种植被的生态水文作用过程。近年来 ,生态与水文相互作用过程的数学模拟和专门模型研制日益成为重要的发展领域 ,同时 ,生态水文学的研究十分注重尺度效应 ,把在一定尺度上获得的水文与生态原理或模型向其它不同尺度转换已成为最具挑战性的问题。山地生态系统成为全球变化研究最为重要的研究场所 ,开展与全球变化相关的生态系统物质与能量循环、生态过程的梯度效应及其与水文过程的耦合关系、生态系统结构与功能及其变化等方面的研究 ,是生态水文学研究最具活力的方向 ,其中建立包含区域气候变化因素的多元生态过程动态模拟模型 ,并使该模型具有不同时空尺度、不同地貌和生态带的广泛适应性是目前广泛关注的热点问题。     

全球尺度水文模型： 机遇、 挑战与展望

水循环发生在全球尺度, 局地和流域水问题的解决也往往需要全球视角, 因此全球尺度水文模型应运而生。从科学意义和国家需求等多个视角, 论述了全球水文学研究的意义和巨大的发展潜力, 系统总结了现有全球尺度水文模型发展现状, 剖析了十余个主流全球尺度水文模型的结构和功能, 以及全球水文-气象-地理信息等全球模型所需数据集。进而分析了现有全球尺度水文模型存在的主要问题和挑战, 为进一步完善模型提供参考。最终分别从模型机理、 大数据、 新技术、 多部门模型耦合等几个方面, 探讨了全球尺度水文模型未来发展的重要方向。     

流域水文模型的发展

本文列出了当今世界上比较流行的15个流域水文模型。对现行概念性集总式流域水文模型的结构和参数的特点进行了评论,指出了这类流域水文模型存在的主要缺陷。对新一代流域水文模型, 即分布式流域水文模型,尤其是其中具有物理基础的分布式流域水文模型,进行了较为深入的分析,指出其之所以优于集总式流域水文模型的主要原因。最后对流域水文模型进一步发展所必须具备的理论和技术条件做了初步讨论。     

都市化对小流域水文影响的研究

综述了受都市化影响的小流域水文特征和研究途径.通过实际观测和概化模型试验,提出了反映都市化水文效应的指标,即当不透水面积比超过20%时,都市化影响表现明显.最后介绍了都市化影响的小流域雨洪计算方法.     

水文山流域土壤水δ~(18)O空间分布异质性研究

流域非饱和带和土壤层的空间异质性是构成水文过程非线性的主要根源,也是水文实验研究中的薄弱环节,特别是其空间分布,传统研究集中于等值线类型的定性描述。研究通过实验流域土壤水δ~(18)O这一非饱和带的主要空间变量,结合传统统计和地统计方法分析不同深度土层δ~(18)O的变化机制和分布空间的分布变异情况,为地统计学方法对水文参数空间变异定量的应用提供数据基础。研究结果显示:15 cm土层土壤水δ~(18)O半方差函数空间模型从纯金模型到高斯和指数模型,再回到纯块金模型,变化剧烈。通过蒸发分馏估算其蒸发强度,得到45cm土层最强(11%),且有关离散性质的极差、标准差和偏度差绝对值也都以45cm土层为最大。说明了在这非饱和带过程中,起关键作用的不是所想象的表面土层,而是中部土层,在水文山实验流域则是地面下的45cm土层;45cm土层的δ~(18)O符合高斯模型和指数模型,且高斯模型中块金与基台值之比C_0/(C_0+C_1)接近于零,说明在下渗、蒸发、迁移以及和土壤中原有δ~(18)O融合后,形成更强的空间自相关性。80cm深度参与"混合"机制的是46d前降雨的"老水",其δ~(18)O的空间自相关性变化则呈现明显滞后性,48 h后才呈现出空间的相关性。可见,经典统计学点参数变量和地统计学区域化变量方法在流域水文参数空间定量方面的有效性,同时在流域水文机制方面出现有意外的、特别是与传统概念相悖的现象。     

水—岩相互作用研究的机遇与挑战

简要回顾水—岩相互作用研究的历史, 它基本经历了一个从水—岩相互作用, 到水—岩—有机物相互作用, 最后到水—岩—气—有机物—微生物相互作用研究的发展历程.近年来, 除基础地质及与矿产资源有关的课题继续深入外, 地下水环境演化与全球变化、含水系统中微量变价元素的迁移、转化与富集、地下水环境污染治理与修复、废物地质处置与CO₂封存等, 已经成为水—岩相互作用领域的研究热点.随着物理、化学、生物等领域中各种新理论和新方法的不断应用, 水—岩相互作用研究面临着新的机遇和挑战, 主要包括: 地下水系统中生物地球化学过程研究、水—岩相互作用中微观机理与宏观地球化学过程的耦合, 以及水—岩相互作用中的同位素分馏及应用等.      

中国土壤学学科发展战略研究报告

土壤是固态地球表面具有生命活动、处于生物与环境间进行物质循环和能量交换的疏松表层。它既是独立的历史自然体，也是最易受人类活动影响、为人类提供食物的自然资源。科学地开发和利用土壤在国民经济建设，特别是在农业生产和改善环境中具有重要作用。土壤学作为主要研究土壤中的物质运动规律及其与环境间相互关系的科学，是农业科学和资源环境科学的基础学科之一。随着自然科学的发展，土壤学的研究不断有新的推进。特别是当前世界进入以经济、科技为主体的竞争年代，人类面临人口－资源－环境间的尖锐矛盾，使土壤学面临着十分严峻的挑战。本报告分析了土壤学的发展趋向及我国土壤学发展中的主要问题，提出了我国土壤学近期研究的重点领域、发展的措施和展望。     

Surface hydrology and soil movement in an arid karst: the Nullarbor Plain,Australia

The Nullarbor Plain is the largest karst area in Australia (220,000 km²) and one of the largest in the world. Its climate is arid (Köppen BWk and BWh), and the surface relief is less than 10m. The landscape is divided into extensive closed karstic depressions separated by low rocky ridges, and the dominant vegetation is chenopod shrubland. The extent and severity of soil degradation has been assessed using remote sensing. GPS rectified images from 1972–1973, 1979, 1983, 1988, and 1991 have been compared for two sites on the Nullarbor. Over the 19 years the total extent of bare soil has reduced significantly, but some areas around water points have degraded and there is some disturbance due to fossorial wombats. Sheet-flow processes occur during intense rainfall events, which happen two or three times per decade. Runoff only occurs after the 10– or 50– year return frequency events, and at these times turbid water ponds in depressions and enters caves. Surface soil sorptivity and hydraulic conductivity differ markedly between ridges and depressions; the ridges are clearly zones of groundwater recharge, while ponding is evident in most depressions. Sorptivity is influenced by the extent and nature of ground cover and cryptogam crusts on the soil. The landscape has been divided into classes on the basis of vegetation type and percentage of foliage cover. In each class the activities of fallout radionuclides will be determined by high resolution spectroscopy. Preliminary results suggest that in undisturbed sites little sediment movement has occurred over the time scale of cesium-137 (the last 35 years) but that the landscape has been well sorted over a much longer time scale. Future work will investigate disturbed sites to estimate relative soil loss during the pastoral period.     

Formative pre-Hispanic agricultural soils in northwest Argentina

Our study area is from an early agricultural archaeological site named “El Tolar” (1st to 9th century AD), located in Tafí Valley (Tucumán, northwest Argentina). The objective was to identify geochemical signatures generated by the sustained agrarian use of soils. Chemical and pedological studies were made in different archaeological contexts. Physical and chemical features, such as bulk density, pH, organic and inorganic phosphorus, and available copper, manganese and iron, were taken into account. The results suggested that a buried paleosol identified was contemporary with the occupation of the site. It also showed characteristics clearly related to pre-Hispanic agrarian production. The concentrations of organic phosphorus and iron in agricultural soils probably reflect the use of fertilizers. The application of geoscience techniques allowed us to obtain important information on their behaviour and socio-economic development. This paper constitutes the first pedogeochemical approach to the study of Argentinean pre-Hispanic agricultural soils.     

国际水文科学研究的新进展

在介绍第七届国际水文科学大会关注热点问题的基础上,总结了近4年来国际水文科学研究的新进展,主要包括：无资料流域水文预测,不确定性、非线性和尺度问题,生态水文学,水文模型及资料获取与参数识别,气候变化的水文响应,水资源可持续利用,城市水文水资源,同位素技术和遥感技术在水文学中应用;提出未来水文学研究的展望。     

Geological and hydrological investigation of a water collection system in arid Jordanian lands

With the increase in population of developing and under developed countries, and with the availability of water resources strained and in many areas deficient, it is quite evident that water conservation and distribution programs need to be adopted on a scale far greater than any yet in use. This requires a more detailed evaluation and development of any water resource. In this study, the geology and geomorphology of the Safawi area northeast of Jordan and the climatic conditions were evaluated as an aid in determining the potential for the collection of surface water. The runoff coefficient, flood frequency, and runoff volumes from some selected valleys were determined through the use of the Soil Conservation Service (SCS) method and other known techniques. The results of this study indicated that the collection of surface water in this arid region is feasible. Estimates were made for the runoff coefficient and annual runoff volumes through the application of the accepted hydraulic engineering methods.     

城市固体废弃物填埋场表层土壤的降雨入渗规律研究

考虑到黄土地区气候特征和地下水的埋藏深度,城市固体废弃物填埋后,其淋洗液主要是以雨水入渗而产生,则上覆土层的厚度应该根据降雨入渗的深度而确定;根据土壤物理学和饱和-非饱和渗流理论,利用土体颗粒分析试验,求得土水特征曲线以及渗透曲线;通过有限元数值模拟,可得各种降雨条件下的水分入渗规律,为填埋场的顶层设计与淋洗液的溶质运移提供参考与依据。     

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)。     

Multicriterial analysis in the investigation of favorable areas for edifications with shallow and deep foundations in the Municipality of Campos dos Goytacazes — Rio de Janeiro, Brazil

The Municipality of Campos dos Goytacazes is located on the northern coast of Rio de Janeiro, Brazil. The city developed on a floodplain and as a consequence of this occupation it has experienced problems with the water table level, drainage system, soil carrying capacity and aquifers' contamination. The purpose of this paper was to accomplish a geological and environmental study, producing interpretive and derived geotechnical maps to analyze the degree of aptitudes or restrictions of the physical environment for urban expansion. In order to do this, the methodology of multicriterial analysis was used, combined with pedological indicators resulting in the elaboration of the Favorability Maps for Buildings (Shallow and Deep Foundations). The remote sensing tools, GIS and GPS, sped up the elaboration of the Information Plans. The maps generated in this work allow us to indicate problems in the physical environment serving as a guide to urbanization. It was verified that the city expands into unsuitable areas and it is recommended as areas for expansion those considered favorable in the outcomes of this research.     

Disciplinary System and Development Strategy for Eco-hydrology

Eco-hydrology is a new discipline developed in recent decades. It is of great significance to accelerate and promote the development of eco-hydrology subject by constructing a perfect discipline system and formulating future development strategies. By reviewing a large number of literatures, this paper systematically combed and expounded the development and evolution of the eco-hydrology, which can be divided into five stages, the embryonic period of eco-hydrology (1970-1986), formulation terminology and the initial exploration period of eco-hydrology (1987-1991), discipline establishment and the initial development period of eco-hydrology (1992-1995), the rapid development period of eco-hydrology (1996-2007) and the improvement period of eco-hydrology (2008-present). Based on the analysis of the development of eco-hydrology, the disciplinary system of eco-hydrology was proposed as a framework of “theory-method-practice-branch discipline”. Finally, combined with the authors’ understanding, this paper put forward the development strategy system of the eco-hydrology, including the disciplinary research plan, the key research project, the country’s major demand, the discipline construction and the international cooperation, which will provide support for the promotion and establishment of a sound disciplinary system of eco-hydrology.     

Yearly changes in the seasonal frequency and duration of short-term acid pulses in some Nova Scotia, Canada streams

 The seasonal frequency and duration of low pH events at three sites located in southwestern Nova Scotia were analyzed using measured and synthetic daily pH data. The basins varied in size from 0.3 to 300 km² and were subject to frequent snowmelt events in winter and spring, as well as occasional runoff events during summer and fall. Results showed that, in order to fill in missing data from periods where collection was interrupted, statistical approximations using discharge were not totally acceptable, as generated data consistently missed the extreme values measured. Despite a lack of totally accurate event pH estimates for periods where daily data were missing, analysis showed that in this region, low pH episodes can occur year-round including summer. The highest probabilities of low pH episodes nevertheless occurred in the winter and spring when snowmelts were frequent. Received: 12 November 1999 · Accepted: 18 July 2000