Conceptualization of runoff processes using a geographical information system and tracers in a nested mesoscale catchment

Tracer investigations were combined with a geographical information system (GIS) analysis of the 31 km² Girnock catchment (Cairngorm Mountains, Scotland) in order to understand hydrological functioning by identifying dominant runoff sources and estimating mean residence times. The catchment has a complex geology, soil cover and topography. Gran alkalinity was used to demonstrate that catchment geology has a dominant influence on baseflow chemistry, but flow paths originating in acidic horizons in the upper soil profiles controlled stormflow alkalinity. Chemically based hydrograph separations at the catchment scale indicated that ～30% of annual runoff was derived from groundwater sources. Similar contributions (23–36%) were estimated for virtually all major sub‐basins. δ¹⁸O of precipitation (mean: ? 9·4‰; range: ? 16·1 to ? 5·0‰) and stream waters (mean: ? 9·1‰; range: ? 11·6 to ? 7·4‰) were used to assess mean catchment and sub‐basin residence times, which were in the order ～4–6 months. GIS analysis showed that these tracer‐based diagnostic features of catchment functioning were consistent with the landscape organization of the catchment. Soil and HOST (Hydrology of Soil Type) maps indicated that the catchment and individual sub‐basins were dominated by hydrologically responsive soils, such as peats (Histosol), peaty gleys (Histic Gleysols) and rankers (Umbric Leptosols and Histosols). Soil cover (in combination with a topographic index) predicted extensive areas of saturation that probably expand during hydrological events, thus providing a high degree of hydrological connectivity between catchment hillslopes and stream channel network. This was validated by aerial photographic interpretation and groundtruthing. These characteristics of hydrological functioning (i.e. dominance of responsive hydrological pathways and short residence times) dictate that the catchment is sensitive to land use change impacts on the quality and quantity of streamflows. It is suggested that such conceptualization of hydrological functioning using tracer‐validated GIS analysis can play an important role in the sustainable management of river basins. Copyright © 2006 John Wiley & Sons, Ltd.     

马粪沟流域不同景观带水文过程

目前高寒水源区完整水文过程规律研究还非常薄弱。应用同位素技术与水化学分析模拟方法来甄别高寒区马粪沟流域不同景观带冰川、积雪、冻土、地表水、地下水和降雨等水体对出山径流的贡献组合与路径,旨在揭示各景观带的水文过程。据端元混合模型计算,在湿季出山径流52%来自地下水补给,其地下水主要是由冻土融水、冰雪融水和降雨下渗转化形成;冰雪带融水占11%;高山寒漠带和灌丛带地表径流占20%;高山草原带约占9%;降雨直接补给占8%。整个流域降雨很少直接产生地表径流,而是在各个景观带转化成壤中流或地下径流,然后汇入河道。     

汾河太原城区段生态建设研究

城市滨水区是城市中最具生命力的景观形态,是城市理想的生态走廊.但是社会经济的发展在给滨水区带来空前繁荣的同时,也带来了建设失控、环境污染、生态失衡等诸多新的问题.阐述城市滨水区的生态特征,并分析了目前城市滨水区建设中存在的生态危机,试图探索一些新的观察与解决问题的措施.同时,通过滨河区治理创造出山西省城市良好的自然景观...     

山东省南四湖湿地植被及其生物量初步研究

通过对南四湖湿地野外实地调查并结合已有资料,对南四湖湿地范围进行了重新界定,分析了湿地的植被状况。并对2006年6月的SPOT 5影像进行解译,绘制了湿地景观格局图并统计各种景观类型的面积。使用湿地植被生物量密度数据计算出整个南四湖湿地植被的生物量为623.37×10^3t,并与1983年资料对比发现南四湖湿地植被生物量已减少了4/5,表明南四湖湿地植被的初级生产能力已经明显减退。     

旅游活动对黄龙景区磷酸盐浓度和水藻生长的影响

由于其独特的钙华景观,黄龙风景区从1992年被联合国教科文组织列入世界自然遗产名录以来,每年吸引数以十万甚至百万计的国内外游客前来游览;然而,可能由于旅游活动的影响,近年来黄龙钙华景观出现了诸多形式的退化,水藻加速生长钙华黑化即是其表现形式之一。为了阐明这一退化现象是否与旅游活动有关,从2010年5月底到11月初的丰水时段,采用野外自动监测和室内分析相结合的方法,对溪流水藻叶绿素含量和水中的磷酸盐浓度变化进行了研究。结果发现,随着景区游客人数的增减,水中磷酸盐浓度呈现出与之一致的变动趋势;同时,叶绿素与磷酸盐间也呈现出明显一致的变动趋势。因此,我们认为,旅游活动增加了黄龙景区的磷酸盐浓度,并促进了水藻的生长,这很可能是黄龙水藻近年来加速生长的重要原因,值得引起有关方面的高度关注。     

若尔盖高原湿地景观与环境要素的DCCA多元相关分析

以9个指标反映若尔盖高原湿地生境的环境特征,在ArcGIS 9.2平台下进行随机样方布设,采用DCCA排序方法定量分析湿地景观与环境要素之间的关系。结果表明：(1)排序前2轴累计解释了湿地景观与环境要素关系的79.4％,表明其具有有效的目标研究显示度;(2)沿地形指数所近似表达的水分状况梯度,研究区各景观类型具有明显的...     

Responses of spatial-temporal variation of Karst ecosystem service values to landscape pattern in northwest of Guangxi,China

The responses of spatiotemporal variation of ecosystem service values (ESVs) to landscape pattern from 1985 to 2005 in a typical Karst area of the northwest Guangxi Zhuang Autonomous Region,China,were examined us-ing remote sensing and geographic information system techniques in this paper.The total ecosystem service values de-clined significantly from 1985 to 1990,and then increased slowly from 1990 to 2005,almost equaled to the 1985 level.The ecosystem service values tended to decline from the west to the...     

Changes of residential land density and spatial pattern from 1989 to 2004 in Jinan City,China

Urban sprawl is driven by a myriad of factors, the predominant one of which is the development of residential land. Selecting part of Jinan City for a case study, we use the landscape metric of percent of landscape (PLAND) to capture residential land growth and density changes in 1989, 1996 and 2004 to illuminate the dynamic process of residential land development. The results indicate that the moving window method and the landscape metrics method are efficient ways to describe residential land density. The residential land showed the greatest change among the built-up land with 1995.68 ha from 1989 to 2004, which is mainly transformed from agriculture land and green space. The urban center area of study area is primarily covered with medium density residential land, and surrounded by high density residential land. The development pattern of residential land exhibited both fill-in (new growth occurs through infilling the free spaces within the developed area) and sprawl processes, influenced by a series of factors, such as urban development policy, conservation of springs, recreational and aesthetic amenities. The findings of the study will help to guide urban planning with a focus on the management and protection of the environment and resources.     

基于景观破碎度分析的传统地域文化景观保护模式——以浙江诸暨市直埠镇为例

传统地域文化景观空间的破碎度研究是在借鉴自然生态空间破碎度研究的基础上,吸收破碎度研究的经验、理论、观点和方法,以整体人文生态系统为对象,将传统地域文化景观看做是人类生存与发展的地方性生境,研究传统地域文化景观的时空过程与景观格局,目的在于探讨传统地域文化景观连续性和整体性保护的模式.以浙江省诸暨市直埠镇作为典型案例,...