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Journal of Integrative Plant Biology 2008年第5期50卷 536-546页

作者： Janneke Westermann Stefan Zerbe Dieter Eckstein Technical University of Berlin Institute of EcologyRothenburgstraβe 12D-12165 BerlinGermany University of Greifswald Institute of Botany and Landscape EcologyGrimmer Straβe 88D-17487 GreifswaldGermany University of Hamburg Department of Wood ScienceDivision of Wood BiologyLeuschnerstraβe 91D-21031 HamburgGermany

The Populus euphratica floodplain forests along the lower reaches of the Tarim River in continental-arid Xinjiang （northwest China） have been declining in recent decades as a result of dam constructions and the withdrawal of water from the river. Since 2000, controlled flooding has been carried out to counteract this process of degradation. However, the consequences of a changing water regime for the floodplain ecosystem are not yet sufficiently investigated. In 2004 we sampled a total of 150 P. euphratica trees along two transects at the middle and lower reaches of the Tarim River to compare the age structure and growth of these two tree populations. The anthropogenic drawdown of the groundwater table had no effect on the average growth of the trees at the lower reaches. However, tree growth abruptly increased after controlled flooding, thus showing distinct signs of recovery.

关键词： arid land controlled flooding Euphrates poplar human impact Populus euphratica tree rings.

Identification and Evolution of Groundwater Chemistry in the Ejin Sub-Basin of the Heihe River, Northwest China

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Pedosphere 2007年第3期17卷 331-342页

作者： SU Yong-Hong FENG Qi ZHU Gao-Feng SI Jian-Hua ZHANG Yan-Wu Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou730000 （China） School of Mathematics and Statistics Lanzhou University Lanzhou 730000 （China）

Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, China, to understand the groundwater evolution, to identify the predominant geochemical processes taking place along the horizontal groundwater flow path, and to characterize anthropogenic factors affecting the groundwater environment based on previous data. The concentrations of major ions and total dissolved solids （TDS） in the groundwater showed a great variation, with 62.5% of the samples being brackish （TDS ≥ 1 000 mg L^-l）. The groundwater system showed a gradual hydro-chemical zonation composed of Na^＋ -HCO3^-, Na^＋ -Mg^2＋ -SO4 ^2 -Cl^-, and Na^＋ -Cl^-. The relationships among the dissolved species allowed identification of the origin of solutes and the processes that generated the observed water compositions. The dissolution of halite, dolomite, and 2- gypsum explained, in part, the presence of Na^＋, K^＋, Cl^-, SO^4 , and Ca^2＋, but other processes, such as mixing, Na^＋ exchange for Ca^2＋ and Mg^2＋, and calcite precipitation also contributed to the composition of water. human activity, in particular large-scale water resources development associated with dramatic population growth in the last 50 years, has led to tremendous changes in the groundwater regime, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Solving these largely anthropogenic problems requires concerted, massive and long-term efforts.

关键词： Ejin Sub-Basin groundwater quality Heihe River human impact water resources development

human’s digital footprints on the Qinghai-Tibet Plateau:Variations during festivals and impacts on nature reserves

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Journal of Geographical Sciences 2021年第2期31卷 179-194页

作者： DU Yunyan TU Wenna LIANG Fuyuan YI Jiawei State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Earth Atmosphericand Geographic Information SciencesWestern Illinois UniversityMacombIL61455USA

Mobile internet and wireless communication technologies have produced unprecedented location-aware *** big geospatial data can be used as a proxy measure of the‘digital footprints’left by us on the planet and provide a valuable opportunity to understand the dynamic and short-term human disturbance on the nature at fine *** study investigated the spatiotemporal variations of human’s digital footprints on the Qinghai-Tibet Plateau using smartphone-users-generated Tencent’s location request *** results showed that human’s digital footprints cover less than 5%of Qinghai and Tibet,exhibiting either a U-shaped or an N-shaped temporal change pattern during the major *** changes of the digital footprints manifested a transition process from dispersion to concentration in Xining and *** disturbance assessment of seven large nature reserves on the plateau showed that the Qinghai Lake is the most disturbed one as shown by 14.6%of its area is stained with human digital footprints and the areal average of footprint intensity is 1.59,and the disturbance was significantly escalated during the National Day *** contrast,the Qangtang and Hoh Xil are the least affected nature reserves with the two indices less than 1%and 0.1,respectively.

关键词： digital footprint space-time variations human impact nature reserve location request

human　Influences　on　the　Development　of　Acid　Sulphate　Soils　in　the　Pearl　River　（the　Zhujiang）　Delta

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Pedosphere 1996年第1期6卷 1-10页

作者： LIN CHUXIA(chool Of Geography, The University of New South Wales, Sydney, N. S. W. 2052 (Australia)) School of Geography University of New South Wales Sydney NSW 2052 Australia

In the Pearl River Delta with more than 1000 years of intensive land reclamation history, the developmentof acid sulphate soils has been generally limited in terms of their acid potential (pyrite content) and spatialextent. This is attributed to the rapid delta progradation, partially resulted from increasing sediment yieldcaused by deforestation within the catchment and the empolderment in the estuarine embayment. Theempolderment practice accompanied by the clearance of mangroves stopped the upward growth of the pyriticlayer on the one hand and limited the vertical accretion of non-pyritic freshwater sediments over the pyriticestuarine sedimellts on the other. In such a case, the Pyritic layer in the area is frequently thin and ofshallow occurrence. Under forced leaching-recharge conditions for the paddy rice cultivation, the leaching ofacid sulphate materials prevails over its production and this leads to a net loss in pyrite oxidation *** excaVation for fishpond farming accelerates Pyrite oxidation due to the direct exposure of the pyriticsediments to air on the pond bunds. Severe acidification can intensify the environmental degradation ofestuarine ecosystems.

关键词： acid sulphate soil fishpond farming human impact pyrite water management

Are Antarctic Specially Protected Areas safe from plastic pollution? a survey of plastic litter at Byers Peninsula, Livingston Island, Antarctica

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Advances in Polar Science 2020年第4期31卷 284-290页

作者： Pablo ALMELA Sergi GONZALEZ Biology Department Autonomous University of MadridMadridSpain Antarctic Group Spanish Meteorological Service(AEMET)BarcelonaSpain

A number of studies have reported in the last decades the presence of plastics in the Southern Ocean,which are liable to reach the coast and accumulate on the Antarctic *** this,there are few data on the amount of plastic pollution on Antarctic beaches below 60°*** we provide valuable information about the presence of plastic debris in Byers Peninsula,Livingston Island,South Shetland Islands,an Antarctic Specially Protected Area(ASPA)and a hotspot for biodiversity.A total of 129 locations with between 1 and 5 items were recorded among the 3 survey sites on Byers *** of the observed items are likely to derive from fishing and local sources such as tourism and research *** discuss the potential impacts of their presence on local fauna and some of the consequences on the Antarctic *** this survey of plastic accumulation in an ASPA,we propose the implementation of mitigation strategies,such as systematic monitoring of the abundance and distribution of plastic waste,in order to identify trends in marine debris and control the levels of plastic pollution in the Maritime Antarctic region.

关键词： marine debris plastic pollution human impact Antarctic Specially Protected Area(ASPA) management Antarctica

On models for landscape connectivity: a case study of the new-born wetland of the Yellow River Delta

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Journal of Geographical Sciences 2002年第2期12卷 63-72页

作者： Yue Tian-xiang Ye Qing-hua Liu Qing-sheng Gong Zheng-hui Institute of Geographic Sciences and Natural Resources Research CAS Beijing China Gudao Monitoring Station of Shengli Oil Field Administration Dongying China

The models for landscape connectivity are distinguished into models for line connectivity, vertex connectivity, network connectivity and patch connectivity separately. Because the models for line connectivity, for vertex connectivity, and for network connectivity have long been studied and have become ripe, the model for patch connectivity is paid special attention in this paper. The patch connectivity is defined as the average movement efficiency (minimizing movement distance) of animal migrants or plant propagules in patches of a region under consideration. According to this definition, a model for landscape connectivity is mathematically deduced to apply to GIS data. The application of model for patch connectivity in the new-born wetland of the Yellow River Delta shows patch connectivity has a negative interrelation with human impact intensity and landscape diversity.

关键词： landscape connectivity mathematical model human impact landscape diversity

human-driven topographic effects on the distribution of forest in a flat, lowland agricultural region

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Journal of Geographical Sciences 2014年第1期24卷 76-92页

作者： Mette V. ODGAARD Peder K. BOCHER Tommy DALGAARD Jesper E. MOESLUND Jens-Christian SVENNING Department of Agroecology Aarhus University Blichers AIIe 20 DK-8830 Tjele Denmark Ecoinformatics & Biodiversity Group Department of Bioscience Aarhus University Ny Munkegade 114DK-8000 Aarhus C Denmark Department of Computer Science Aarhus University Abogade 34 DK-8200 Aarhus N Denmark

Complex topography buffers forests against deforestation in mountainous regions. However, it is unknown if terrain also shapes forest distribution in lowlands where human impacts are likely to be less constrained by terrain. In such regions, if important at all, to- pographic effects will depend on cultural-historical factors and thus be human-driven （an- thropogenic） rather than natural, except in regions where the general climate or extreme soils limit the occurrence of forests. We used spatial regression modeling to assess the extent to which topographic factors explain forest distribution （presence-absence at a 48x48 m resolu- tion） in a lowland agricultural region （Denmark, 43,075 km2） at regional and landscape scales （whole study area and 10x10 km grid cells, respectively）, how landscape-scale for- est-topography relationships vary geographically, and which potential drivers （topographic heterogeneity, forest cover, clay content, coastal/inland location） determine this geographic heterogeneity. Given a moist temperate climate and non-extreme soils all landscapes in Denmark would naturally be largely forest covered, and any topographic relationships will be totally or primarily human-driven. At regional scale, topographic predictors explained only 5% of the distribution of forest. In contrast, the explanatory power of topography varied from 0%-61% at landscape scale, with clear geographic patterning. Explanatory power of topog- raphy at landscape scale was moderately dependent on the potential drivers, with topog- raphic control being strongest in areas with high topographic heterogeneity and little forest cover. However, these conditioning effects were themselves geographically variable. Our findings show that topography by shaping human land-use can affect forest distribution even in flat, lowland regions, but especially via localized, geographically variable effects.

关键词： Europe forest cover geographically weighted regression human impact landscape development topography vegetation distribution.

STAGES OF LATE HOLOCENE GULLY DEVELOPMENT IN THE CENTRAL RUSSIAN PLAIN

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International Journal of Sediment Research 2005年第3期20卷 70-78页

作者： V. R. BELYAEV,E. A. EREMENKO ,A. V. PANIN,Y. R. BELYAEV The Laboratory of Soil Erosion and Fluvial Processes Faculty of Geography Moscow State University GSP-2 Vorob’evy Gory Moscow 119992 Russia.Dr. The Laboratory of Soil Erosion and Fluvial Processes Faculty of Geography Moscow State University GSP-2 Vorob’evy Gory Moscow 119992 Russia.Dr.

Two gullies located in the Protva River basin （central part of European Russia, 100 km southwest of Moscow） were studied to investigate the history of their development during Late Holocene. This case study included detailed topographic and geomorphologic surveys, geological cross-sections, and radiocarbon dating of organic matter in gully sediments. For both gullies, incision of the long profile occurred for most of the Holocene, as indicated by the limited presence of infill sediment. However, interruptions of incisions occurred in both gullies during the last3.5 ka （the Chugunkin gully） or2.0 ka （the Uzkiy gully）, as evident from stratigraphic interpretation of the sediment record. Periods of surface stabilization are represented by buried soil horizons, whereas relatively thick sediment layers suggest periods of predominant aggradation. Similarities and differences in discovered sequences of erosion and accumulation stages for the two gullies point out the importance of distinguishing between local and regional controls. Evidence of the role of internal system behavior and self-development in the gully long-term evolution is clear from asynchronous response of different parts of gullies. In recent times （500 years）, active agricultural development of the study territory resulted in accelerated incisions, followed by deposition of catchment-derived material. The latter was limited to the upper parts of the gullies, while incisions have continued in the middle and lower parts. The impact of human activities （500 years） has been very limited. This suggests that within the forest zone of the Russian Plain many gullies which were earlier attributed to anthropogenic factors are, in reality, due to natural phenomena.

关键词： Gully erosion Incision and infill Environmental change Late Holocene human impact Russian Plain

Edge Effects of Oil Pipeline Canopy Openings on Tree Community Structure and Dynamics in a Montane Atlantic Forest

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Journal of Geoscience and Environment Protection 2016年第7期4卷 132-140页

作者： Pablo J. F. Pena Rodrigues Leticia R. Melo Rodolfo C. R. de Abreu Mariana A. Iguatemy Instituto de Pesquisas Jardim Botanico do Rio de Janeiro Rio de Janeiro-RJ Brazil

The Atlantic forest has historically been severely deforested, and only fragments currently remain that are subject to a wide variety of anthropogenic impacts, including edge effects that can cause structural and functional degradation. The Tinguá Biological Reserve-RJ comprises approximately 26,000 hectares of well-preserved Atlantic Forest, but it is subject to impacts caused by two canopy openings along oil pipelines. Comparisons were made between pipeline edges and forest interiors to evaluate edge effects on the structure and dynamics of those tree communities. Tree densities were higher along forest edges, apparently increasing over time. Tree basal areas, on the other hand, have decreased along edges due to higher mortality rates. Linear canopy opening edges showed higher densities of small trees, while the interior had more very large trees, indicating changes in successional processes and community structural patterns due to edge effects.

关键词： Fragmentation Disturbance human-Modified Habitats Linear Canopy Openings human impact

Gastropods Diversity in Thondaimanaru Lagoon (Class: Gastropoda), Northern Province, Sri Lanka

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Journal of Geoscience and Environment Protection 2021年第3期9卷 21-30页

作者： Amarasinghe Arachchige Tiruni Nilundika Amarasinghe Thampoe Eswaramohan Raji Gnaneswaran Department of Zoology Faculty of Science University of Jaffna Jaffna Sri Lanka

Thondaimanaru lagoon (TL) is one of the three lagoons in the Jaffna Peninsula, Sri Lanka. TL (N-9.819584, E-80.134086), which is 74.5 Km2. Fringing these lagoons are mangroves, large tidal flats and salt marshes. The present study is carried out to assess the diversity of gastropods in the northern part of the TL. The sampling of gastropods was performed by using quadrat method from July 2015 to June 2016. Different sites were selected and rainfall data, water temperature, salinity of the water and GPS values were collected. Collected gastropod shells were classified using standard taxonomic keys and their morphological as well as morphometrical characteristics were analyzed. A total of 23 individual gastropods were identified from the lagoon which belongs to 21 genera of 15 families among them 11 gastropods were identified up to species level.

关键词： Biodiversity Quadrat Sampling Conservation human impact