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Advances in Climate Change research 2015年第3期6卷 159-170页

作者： ZHANG Peng Deliang CHEN Hans W.LINDERHOLM ZHANG Qiong regional Climate group Department of Earth Sciences University of Gothenburg Bert Bolin Centre for Climate research Department of Physical Geography and Quaternary Geology Stockholm University

Tree-ring based temperature reconstructions have successfully inferred the past inter-annual to millennium scales summer temperature variability. A clear relationship between annual and summer temperatures can provide insights into tile variability of past annual mean tem- perature from the reconstructed summer temperature. However, how similar are summer and annual temperatures is to a large extent still unknown. This study aims at investigating the relationship between annual and summer temperatures at different timescales in central Sweden during the last millennium. The temperature variability in central Sweden can represent large parts of Scandinavia which has been a key region for dendroclimatological research. The observed annual and summer temperatures during 1901-2005 were firstly decomposed into different frequency bands using ensemble empirical mode decomposition （EEMD） method, and then the scale-dependent relationship was quantified using Pearson correlation coefficients. The relationship between the observed annual and summer temperatures determined by the instrumental data was subsequently used to evaluate 7 climate models. The model with the best performance was used to infer the relationship for the last millennium. The results show that the relationship between the observed annual and summer temperatures becomes stronger as the timescale increases, except for the 4--16 years timescales at which it does not show any relationship. The summer temperature variability at short timescales （2--4 years） shows much higher variance than the annual variability, while the annual temperature variability at long timescales （〉32 years） has a much higher variance than the summer one. During the last millennium, the simulated summer temperature also shows higher variance at the short timescales （2-4 years） and lower variance at the long timescales （〉1024 years） than those of the annual temperature. The relationship between the two temperatures is generally close at

关键词： Annual temperature Summer temperature Central Sweden Climate model simulation Scale-dependent similarity

Sediment generation and soil mound denudation in areas of high-density tree throw along a river valley in the Jura Mountains, Switzerland

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Journal of Mountain Science 2021年第2期18卷 377-391页

作者： Philip GREENWOOD Jan BAUER Nikolaus J KUHN physical geography&Environmental Change research group Department of Environmental SciencesUniversity of BaselKlingelbergstrasse 27Basel-4056Switzerland

A preliminary field-based investigation was undertaken in a small(<10 km^(2))river valley located in the mountainous Jura region of northwest *** aims of the work were to assess sediment generation and annual sediment transport rates by tree throw on forested hillslopes,and to document surface hydrology characteristics on four fresh soil mounds associated with recent tree throws over a 24-day monitoring *** the soil mounds,average sediment recovery ranged from 7.7-28.2 g(dry weight),equivalent to a suspended sediment concentration of 145.2-327.8 g L^(-1),and runoff coefficients ranged from 1.0%-4.2%.Based on a soil bulk density value of 1,044 kg m^(-3),upslope runoff generation areas were denuded by an average 0.14 mm by the end of the 24-day monitoring period,representing an erosion rate equivalent to 2.1 mm yr^(-1).A ca.50 cm high soil mound could therefore feasibly persist for around 200-250 *** tree throw work,the dimensions of 215 individual tree throws were measured and their locations mapped in 12 separate locations along the river valley representing a cumulative area equivalent to 5.3 ha(***,43 per ha).Tree throws generated a total of 20.1 m^(3) of fine-sediment(<2 mm diameter),or the equivalent of 3.8×10^(-4) m^(3) m^(-2).The process of tree throw was originally attributed to two extreme weather events that occurred in west and central Europe in late December *** the 18-year period since both storms,this represents an annual sediment transport rate of 2.7×10^(-5) m^(3) m^(-1) yr^(-1).Exploring the relationship with wind on fall direction,65.5%of tree throws(143)generally fell in a downslope direction irrespective of hillslope aspect on which they were *** infers that individual storms may not have been responsible for the majority of tree throws,but instead,could be associated with root *** the high density of tree throws and their relative maturity(average age 41 years),we hypothesise that once tr

关键词： Tree throw Hillslope processes Sediment generation mechanism Sediment transport rate Soil mound Ibach river valley

Contrasted Impact of Land Abandonment on Soil Erosion in Mediterranean Agriculture Fields

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Pedosphere 2018年第4期28卷 617-631页

作者： Jesus RODRIGO-COMINO Carlos MARTINEZ-HERNANDEZ Thomas ISERLOH Artemi CERDA Instituto de Geomorfología y Suelos Department of Geography University of Málaga Mdlaga 29071 (Spain) Department of physical geography Trier University Trier 54286 (Germany) Department of geography University of Murcia Murcia 30001 (Spain) Soil Erosion and Degradation research group Department of Geography University of Valencia Valencia 46010 (Spain)

Abandonment of agricultural land results in on- and off-site consequences for the ecosystem. In this study, 105 rainfall simulations were carried out in agriculture lands of the Mediterranean belt in Spain （vineyards in Malaga, almond orchards in Murcia, and orange and olive orchards in Valencia） and in paired abandoned lands to assess the impact of land abandonment on soil and water losses. After abandonment, soil detachment decreased drastically in the olive and orange orchards, while vineyards did not show any difference and almond orchards registered higher erosion rates after the abandonment. Terraced orchards of oranges and olives recovered a dense vegetation cover after the abandonment, while the sloping terrain of almond orchards and vineyards enhanced the development of crusts and rills and a negligible vegetation cover resulted in high erosion rates. The contrasted responses to land abandonment in Mediterranean agricultural lands suggest that land abandonment should be programmed and managed with soil erosion control strategies for some years to avoid land degradation.

关键词： erosion rate Mediterranean crop rainfall simulation terrace vegetation cover

Debris Flows Risk Analysis and Direct Loss Estimation:the Case Study of Valtellina di Tirano,Italy

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Journal of Mountain Science 2014年第2期11卷 288-307页

作者： Jan BLAHUT Thomas GLADE Simone STERLACCHINI Department of Engineering Geology Institute of Rock Structure and Mechanics Academy of Sciences of the Czech Republic Geomorphic Systems and Risk research group Department of Geography and Regional Research University of Vienna Institute for the Dynamic of Environmental Processes National Research CouncilCNR-IDPA

andslide risk analysis is one of the primary studies providing essential instructions to the subsequent risk management process. The quantification of tangible and intangible potential losses is a critical step because it provides essential data upon which judgments can be made and policy can be formulated. This study aims at quantifying direct economic losses from debris flows at a medium scale in the study area in Italian Central Alps. Available hazard maps were the main inputs of this study. These maps were overlaid with information concerning elements at risk and their economic value. Then, a combination of both market and construction values was used to obtain estimates of future economic losses. As a result, two direct economic risk maps were prepared together with risk curves, useful to summarize expected monetary damage against the respective hazard probability. Afterwards, a qualitative risk map derived using a risk matrix officially provided by the set of laws issued by the regional government, was prepared. The results delimit areas of high economic as well as strategic importance which might be affected by debris flows in the future. Aside from limitations and inaccuracies inherently included in risk analysis process, identification of high risk areas allows local authorities to focus their attention on the “hot-spots”, where important consequences may arise and local （large） scale analysis needs to be performed with more precise cost-effectiveness ratio. The risk maps can be also used by the local authorities to increase population’s adaptive capacity in the disaster prevention process.

关键词： Debris flows Risk analysis Economic losses Central Alps Italy

Population Growth and Sustainability of Common Property Resource Management Systems in the Eastern Hindu Kush:The Use of Communal Fodder Resources in Mehlp Valley,North Pakistan

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Journal of Mountain Science 2009年第4期6卷 380-393页

作者： Fazlur-Rahman Department of geography Urban & regional Planning University of PeshawarUniversity Town

In common property studies,increasing number of users has been considered as a major threat for the long-term sustainability of natural resources. This perception has been true in a few cases. However,the 40-years empirical research conducted in a variety of environmental settings,reveals that population pressure is not the only factor responsible for the degradation of natural resources. In remote areas,where the local inhabitants highly depend on available natural resources for subsistence livelihood,the economically important resources are kept under different ownership regimes. The local inhabitants have established autochthonous insti-tutions,and formulated rules and regulations for proper management of these resources. In this paper an attempt has been made to explore the response of a small fodder user community to the increasing population. For this purpose a micro-level study has been conducted in a remote mountain environment in the eastern Hindu Kush. For this research,data has been collected through fieldwork and focus group discussion. The results of this study reveal that fodder user communities have responded very well to the problem of population pressure. To maintain equity and long-term sustainability they have adopted a number of strategies including changing the ownership,and a resource kept under private ownership at the time of low population has been changed to a common property with increase in population. Based on this study it can be concluded that in mountainous areas and fragile environment the local inhabitant have both the capacity and capability to change their behaviour with regard to changing resource productivity as well as increasing number of users,and this situation does not always lead to the tragedy of commons.

关键词： Mixed mountain agriculture Tragedy of the commons Livelihood strategies Population growth

Catchment soils as a factor of trace metal accumulation in sediments of the reservoir Klingenberg(eastern Ore Mountains, Germany)

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Journal of Environmental Sciences 2019年第12期31卷 1-14页

作者： Jens Hahn Christian Opp Raphael Ganzenmuller Anntke Ewert Birgit Schneider Nina Zitzer Gabriela Laufenberg Philipps-University of Marburg Working Group for Hydro-and Soil GeographyDeutschhausstr.1035037 MarburgGermany University of Leipzig Institute of GeographyPhysical GeographyJohannisallee 19a04103 LeipzigGermany Philipps-Uniuersity o/Marbitrg Mass SpectrometryMarbacher Weg 6-1035037 MarburgGermany

The release and accumulation dynamics of trace metals in soils and aquatic sediments were exemplarily investigated in the catchment area of the Reservoir Klingenberg(Germany).Catchment soils were examined for mobilizable and total concentrations of arsenic(As),cadmium(Cd),chrome(Cr),iron(Fe),manganese(Mn),nickel(Ni),lead(Pb),and zinc(Zn)and compared with trace metal quantities accumulated in riverbed and reservoir *** comparison of all samples showed relatively small variations of Cr(7.96–46.0 mg/kg),Fe(7.79–40.4 g/kg),and Ni(6.06–56.5 mg/kg),while stronger differences were found for As(11.2–164 mg/kg),Cd(0.14–30.5 mg/kg),Mn(0.08–1.84 g/kg),Pb(20.7–183 mg/kg),and Zn(69.1–916 mg/kg).The catchment soils were slightly enriched by Cd,Pb,and *** Cd and Zn were characterized by large mobilizable *** mean trace metal concentrations in riverbed sediments were higher than in catchment soils,while reservoir sediments accumulated the highest amounts of the analyzed *** enrichment of trace metals in reservoir sediments was generally determined by the sedimentation of fine particles,while the distribution of As,Fe,and Mn was additionally impacted by redox *** Cd and Zn,which in comparison were most enriched in riverbed and reservoir sediments,a significant release from soils by leaching processes was *** accumulation of As and Pb in reservoir sediments was influenced to a greater extent by soil erosion and by anthropogenic or chalcogen sources in the catchment.

关键词： Trace metals Exchangeable forms Soil Sediment Catchment Sources

Geographical distribution of Aralia elata characteristics correlated with topography and forest structure in Heilongjiang and Jilin Provinces,Northeast China

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Journal of Forestry research 2021年第3期32卷 1115-1125页

作者： Hongxu Wei Guoshuang Chen Xin Chen Hengtian Zhao research group of Urban Forests and Urban Wetlands Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102People’s Republic of China research group of Understory Plants Resources Northeast Institute of Geography and Agroecology(Harbin)Chinese Academy of SciencesHarbin 150081People’s Republic of China

The Araliaceae family consists of numerous species of medical plants of significant value as non-wood forest *** conserve and culture these plants in natural forest stands is an important undertaking which should be implemented according to the relationship between forest structure and understory *** this study,thirtyfive plots were established in natural A ralia elata *** individual and denser populations were found in the northern and in the eastern regions,*** population densities and individual leaf weight increased along *** contrast,their relationship with elevation and DBH were *** with the altitude gradient,both height and root-collar diameter increased but population density ***-collar diameter and population density decreased with latitude and DBH,***,dominant trees unlikely enforced strong disturbance to the development of understory *** populations unless concerning some specific topographic factors.

关键词： Aralia elata Chinese angelica-tree Stand quality Geographical distribution Undergrowth Nontimber forest species

Efficiency of local minima and GLM techniques in sinkhole extraction from a LiDAR-based terrain model

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International Journal of Digital Earth 2019年第9期12卷 1067-1082页

作者： Péter Enyedi Melinda Pap Zoltán Kovács László Takács-Szilágyi Szilárd Szabó a Department of physical geography and Geoinformatics University of DebrecenDebrecenHungary Internet of Things research Institute Eszterházy Károly University of Applied SciencesEgerHungary

The aim of this paper was to study reliable automated delineationpossibilities of karst sinkholes using a LiDAR-based digital terrain model(DTM) with pixel-based classifications. We applied two approaches toextract sinkholes: (1) general linear modeling (GLM) with morphometricindices derived from DTM;(2) and a local minima-based delineationusing only LiDAR DTM as the input layer. The outcome of the localminima was significantly different from the reference ones but found allthe sinkholes without previous knowledge of the area. The GLM-basedoutcome did not differ statistically from the reference. Results showedthat these approaches were efficient in detecting sinkholes based onLIDAR derivatives, and can be used for risk assessment and hazardpreparedness in karst areas: GLM had an overall accuracy of 89.5% andlocal minima had an accuracy of 92.3%;both methods identifiedsinkholes but also had commission errors, identifying depressions assinkholes.

关键词： Karst mapping sinkhole identification general linear model statistical evaluation sink fill

Can a dam type of an alpine lake be derived from lake geometry?A negative result

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Journal of Mountain Science 2021年第3期18卷 614-621页

作者： Adam EMMER Vojtěch CURIN University of Graz Institute of Geography and Regional ScienceCascade|The Mountain Processes and Mountain Hazards GroupGraz 8010Austria Czech Academy of Sciences Prague 16500Czechia Global Change research Institute Czech University of Life Sciences PragueFaculty of Environmental SciencesBrno 60300Czechia

Glacial lake outburst floods(GLOFs)represent one of the most serious hazard and risk in deglaciating high mountain regions worldwide and the need for GLOF hazard and risk assessment is *** a consequence,numerous region-and nation-wide GLOF assessment studies have been published *** studies cover large areas and consider hundreds to thousands of lakes,prioritizing the hazard posed by ***,certain simplification is required for executing such studies,often resulting in neglecting qualitative characteristics which would need manual *** lake dam types(e.g.,bedrock-dammed,moraine-dammed)are often not distinguished,despite they control GLOF mechanism(dam overtopping/dam breach)and thus GLOF *** this study,we explore the potential of easily measurable quantitative characteristics and four ratios to approximate the lake dam *** dataset of 851 lakes of the Cordillera Blanca suggests that while variances and means of these characteristics of individual lake types differ significantly(F-test,t-test),value distribution of different geometrical properties can’t be used for the originally proposed purpose along the *** only promising results are obtained for extreme values(selected bins)of the *** instance,the low width to length ratio indicates likely morainedammed lake while the high value of ratio indicating round-shape of the lake indicates increased likelihood of bedrock-dammed ***,we report a negative result of our experiment since there are negligible differences of relative frequencies in most of the bins along the spectra.

关键词： Alpine lake High mountain lake GLOFs Glacial lake Moraine-dammed Bedrock-dammed Negative result Cordillera Blanca