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Comprehensive analysis of glacier recession(2000-2020)in the Nun-Kun Group of Glaciers,Northwestern Himalaya

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Journal of Mountain Science 2024年第3期21卷 768-785页

作者： Shakil Ahmad ROMSHOO Ummer AMEEN Mustafa Hameed BHAT Tariq ABDULLAH Department of geoinformatics University of KashmirSrinagarKashmir 190006India Islamic University of Science and Technology AwantiporaKashmir 192122India centre of Excellence for Glacier studies in the Western Himalaya University of KashmirSrinagarKashmir 190006India

Himalayan glaciers are shrinking rapidly,especially after *** shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger *** this study,changes of 48 glaciers situated around the twin peaks of the Nun and Kun mountains in the northwestern Himalaya,hereafter referred to as Nun-Kun Group of Glaciers(NKGG),were investigated using Landsat satellite data during *** in glacier area,snout position,Equilibrium Line Altitude(ELA),surface thickness and glacier velocity were assessed using remote sensing data supplemented by field *** study revealed that the NKGG glaciers have experienced a recession of 4.5%±3.4%and their snouts have retreated at the rate of 6.4±1.6 m·a^(-1).Additionally,there was a 41%increase observed in the debris cover area during the observation *** the geodetic approach,an average glacier elevation change of-1.4±0.4 m·a^(-1)was observed between 2000 and *** observed mass loss of the NKGG has resulted in the deceleration of glacier velocity from 27.0±3.7 m·a^(-1)in 2000 to 21.2±2.2 m·a^(-1)in *** ELA has shifted upwards by 83.0±22 m during the *** morphological and topographic factors showed a strong influence on glacier ***,a higher recession of 12.9%±3.2%was observed in small glaciers,compared to 2.7%±3.1%in larger *** debris-covered glaciers showed lower shrinkage(2.8%±1.1%)compared to the clean glaciers(9.3%±5%).The glacier depletion recorded in the NKGG during the last two decades,if continued,would severely diminish glacial volume and capacity to store water,thus jeopardizing the sustainability of water resources in the basin.

关键词： Nun-Kun range Glacier recession Glacier snout Remote Sensing Himalaya Glacier velocity

Spatio-temporal patterns and changes in environmental attitudes and place attachment in Gauteng, South Africa

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Geo-Spatial Information Science 2021年第4期24卷 666-677页

作者： Simangele Dlamini Solomon G.Tesfamichael Gregory D.Breetzke Tholang Mokhele Department of Geography Environmental Management and Energy StudiesUniversity of JohannesburgJohannesburgSouth Africa Geospatial Analytics eResearch Knowledge CentreHuman Sciences Research CouncilPretoriaSouth Africa Department of Geography Geoinformatics and MeteorologyUniversity of PretoriaPretoriaSouth Africa

In this study,we employed a number of geospatial techniques to examine the spatiotemporal patterns and changes of environmental attitudes and place attachment values in the Gauteng province of South *** data were obtained from the Gauteng City Region Observatory’s Quality of Life Survey collected at three separate points in time,namely 2013,2015,and *** indicated that wards(smallest administrative and analysis units)located on the urban periphery of Gauteng,which are generally less affluent,largely held more negative environmental attitudes and place attachment values during the three time *** contrast,centrally located wards,which are generally more affluent,expressed more positive environmental attitudes but less place attachment values,especially in *** findings of this research not only highlight the complex spatio-temporal distribution of environmental attitudes and place attachment values throughout Gauteng but also empha-size the need for spatially targeted state interventions for future environmental planning within the province.

关键词： Spatio-temporal changes environmental attitudes place attachment Gauteng spatial patterns

Upstream-downstream linkages of hydrological processes in the Himalayan region

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Ecological Processes 2014年第1期3卷 51-66页

作者： Santosh Nepal Wolfgang-Albert Flugel Arun Bhakta Shrestha International centre for Integrated Mountain Development(ICIMOD) KathmanduNepal Department of geoinformatics Hydrology and ModellingFriedrich Schiller UniversityJena(FSU-Jena)Germany

Understanding the upstream-downstream linkages in hydrological processes is essential for water resources planning in river *** there are many studies of individual aspects of these processes in the Himalayan region,studies along the length of the basins are *** study summarizes the present state of knowledge about linkages in hydrological processes between upstream and downstream areas of river basins in the Himalayan region based on a literature *** paper studies the linkages between the changes in the physical environment of upstream areas(land use,snow storage,and soil erosion)and of climate change on the downstream water availability,flood and dry season flow,and erosion and *** is argued that these linkages are complex due to the extreme altitudinal range associated with the young and fragile geology,extreme seasonal and spatial variation in rainfall,and diversity of anthropogenic *** on the findings,the paper concludes that integrated systems analysis is required to understand the holistic complexity of upstream-downstream linkages of hydrological processes in the river basin *** integrated land and water resources management(ILWRM)approach can be instrumental in developing adaptive solutions to problems and can also enable stakeholders of upstream and downstream areas with various interests and needs to work together for the better utilization and management of land and water *** a part of this,the specific circumstances of the upstream communities,who live in fragile and inaccessible mountain areas with limited resource opportunities,should be taken into account so that incentive mechanisms can be established to encourage and acknowledge their contribution.

关键词： Integrated land and water resources management Himalayan region Integrated systems analysis geoinformatics Physical linkages Value of environmental services

Cretaceous volcanic-intrusive magmatism in western Guangdong and its geological significance

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Science China Earth Sciences 2006年第7期49卷 696-713页

作者： S. Y. O’Reilly GEMOC ARC National Key centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Systematic zircon LA-ICPMS U-Pb dating reveals that Cretaceous volcanic-intrusive activities developed in western Guangdong. Representative volcanic rocks, i.e. Maanshan and Zhougongding rhyodacites, have zircon U-Pb isotopic ages of 100±1 Ma, and the intrusive ones in-cluding the Deqing monzonitic granite body and the Xinghua granodiorite body in the Shidong com-plex, as well as the Tiaocun granodiorite body in the Guangping complex yield ages of 99±2 Ma, ca. 100 Ma, and 104±3 Ma respectively. The biotite-granites of the Shidong complex main body (461±35 Ma) and that of the Guangping complex (444±6 Ma) are Caledonian. In spite of the big time interval between Cretaceous volcanic-intrusive magmatisms and Caledonian intrusive ones, both of them are characterized by enrichment in Rb, Th, Ce, Zr, Hf, Sm, depletion in Ba, Nb, Ta, P, Ti, Eu, and weakly REE tetrad effect. Eu negative anomalies are: Cretaceous volcanic rocks (Eu/Eu*=0.74), Cretaceous intrusive rocks (Eu/Eu*=0.35―0.58), Caledonian biotite granites (Eu/Eu*=0.31―0.34). studies of Sr-Nd isotope data show that all these igneous rocks have high initial 87Sr/86Sr ratios (0.7105―0.7518), and low εNd(t) values (?7.23―?11.39) with their Nd two-stage model ages ranging from 1.6―2.0 Ga, which suggest that they all derived from the Proterozoic crustal basement of southeast China. The occurrence of Cretaceous volcanic-intrusive magmatisms in western Guangdong is related with the important lithospheric extension event in southeast China (including Nanling region) at ca. 100 Ma. The “volcanic line” defined by the large scale Mesozoic intermediate-acidic volcanic magmatisms in southeast China may further extend to the southwest margin of Nanling region.

关键词： Cretaceous, volcanic-intrusive rocks, zircon U-Pb dating, Sr-Nd isotope, western Guangdong.

Morphometric Analysis of Kakoi River Watershed for Study of Neotectonic Activity Using Geospatial Technology

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International Journal of Geosciences 2017年第11期8卷 1384-1403页

作者： Francis Sangma Guru Balamurugan centre for geoinformatics Jamsetji Tata School of Disaster Studies (JTSDS) Tata Institute of Social Sciences Mumbai India

Morphometric analysis is defined as the quantitative measurement of landscape shape. Morphometric studies of a watershed helps the researcher to compare different landform and calculate the geomorphic indices that may be useful for identifying a particular characteristic such as the level of neotectonic activity in a watershed. The present study has been carried out in Kakoi River Watershed which is a part of Lower Subansiri River Basin in Assam. The study area is geo-dynamically unstable region characterized by active faults, continuing crustal movements and complicated structural region which fall under the seismic zone V of India. In recent century, the Lower Suabsiri River Basin has gone tremendous morphological changes due to active tectonics activities. After the Assam Earthquake of 1950, some of the rivers like Subansiri and its tributaries Dirgha, Kadam and Kakoi suddenly changed their channels giving birth to new channels. The present study is to examine the neotectonic domains and the changes of river course. The geomorphic indices such as Hypsometric Integral (HI), Elongation ratio (Re), Asymmetry Factor (AF), Stream-length Gradient Index (SI), Mountain Front Sinuosity (Mfs), Basin shape index (Bs), Ratio of Valley floor width to Valley Height (Vf) and Channel sinuosity (S) etc. have been studied from remote sensing data. The results shows that the study area is under active tectonic area based on Vf (0.301), Rl (0.461), Bs (3.6), Sl (165.73) and other parameters such as S (1.38) and Mfs (2.02) indicated as moderate active tectonic region. Utilization of geospatial technology and remote sensing data in the present study becomes more reliable and helpful in analyzing, monitoring and understanding the landform changes in a watershed.

关键词： Morphometric Geomorphic Indices Neotectonics Geospatial Technology

People’s perception and socioeconomic determinants of soil erosion:A case study of Samanalawewa watershed, Sri Lanka

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International Journal of Sediment Research 2010年第4期25卷 323-339页

作者： E.P.N. UDAYAKUMARA R.P.SHRESTHA L.SAMARAKOON D.SCHMIDT-VOGT Natural Resource Management Field of Study School of Environment Resources and Development Asian Institute of Technology Natural Resources Management Field of Study School of Environment Resources and Development Asian Institute of Technology geoinformatics centre Asian Institute of Technology centre of Mountain Ecosystem studies Kunming Institute of Botany Chinese Academy of Sciences 3/F Library Building Heilongtan

Though soil erosion is an important concern in Sri Lanka, there is a dearth of baseline information on soil erosion in many ofits watersheds, which obstructs monitoring of soil erosion and mitigating its effects. In order to assess soil erosion in a critical watershed and to identify its determinants, the Samanalawewa watershed, which contains one of the main hydropower generating reservoirs in Sri Lanka, was selected for this study. Remote-sensing (RS) and geographic information system (GIS) based modeling as well as field experiments were employed to assess and map soil erosion rates. Results indicated that the current rate of soil erosion ranges from 0 to 289 t/ha/yr, and that the average rate of soil erosion has been declining from 20 to 4 t/ha/yr over a period from 1986 to 2008. The current rate of soil erosion is, however, still about 14 to 33 times greater than the natural soil generation rate. Socioeconomic factors and peoples’ perception of soil erosion and soil conservation measures were examined using data collected through a household survey. Multiple regression analysis with eighteen covariates of socioeconomic characteristics yielded eleven socioeconomic variables, viz. household size, farm labor, education, land tenure, conservation cost, training, committee membership, professional competencies, income, distance, and financial capital as the predictor variables of soil erosion. Farmers identified improper soil and crop management practices as the major causes of erosion. The adoption of conservation measures, their effectiveness, and their impact on ecosystem services were also examined.

关键词： Soil erosion People perception Determinants of soil erosion Conservation measures Sri Lanka

Snow and regolith albedo variations using CRISM data at McMurdo crater,Mars

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Earth and planetary Physics 2024年第2期8卷 338-355页

作者： Sehajpal Singh Deepak Singh centre of studies in Resources Engineering Indian Institute of Technology BombayMumbaiIndia

The cryosphere component provides the most reliable and insightful indications of any planet’s climate *** data from the Compact Reconnaissance Imaging Spectrometer for Mars(CRISM),we develop a novel approach to determining the broadband Visible and Near Infrared(VNIR)albedo of the Martian *** study focuses on albedo changes in the McMurdo crater,part of Mars’s south polar layer *** compare seasonal and interannual variations of the McMurdo surface albedo before,during,and after the Global Dust Storm(GDS)of Martian Year(MY)*** the seasons progressed from spring to summer,the mean albedo in MY 32 and 34 plunged by over 40%,by about 35%in MY 33,and by slightly more than 30%in MY *** interannually,however,mean albedo values within both seasons(spring and summer)exhibited no significant differences in those same ***,interannual albedo difference maps reveal albedo variation of more than±0.3 in certain regions of the *** only snow-covered pixels,interannual albedo differences suggest that Mars dust had a pervasive impact on Mars’s *** in maximum and minimum albedo values as high as 0.5 were observed,depending upon differences in the dust levels in Martian snow/*** maximum and the minimum snow albedo values were lowest in MY 34,indicating the effect of the intense dust storm event that *** average snow albedo decreased from 0.45 in MY 32 to 0.40 in MY 33 and to 0.33 in MY 34,and then rose back to 0.40 in MY *** trajectory suggests a temporary deposition of dust,partially reversed after the GDS by self-cleaning mechanisms(local aeolian process and CO_(2)sublimation/deposition cycle).

关键词： Mars Martian ice albedo dust storm Mars surface Martian climate

Prediction of solar activities:Sunspot numbers and solar magnetic synoptic maps

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Science China Earth Sciences 2024年第8期67卷 2460-2477页

作者： Rui ZHUO Jiansen HE Die DUAN Rong LIN Ziqi WU Limei YAN Yong WEI School of Earth and Space Sciences Peking UniversityBeijing 100091China College of Advanced Interdisciplinary studies National University of Defense TechnologyChangsha 410073China centre for Mathematical Plasma Astrophysics Department of MathematicsKU LeuvenLeuven 3001Belgium Key Laboratory of Earth and planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The evolution of solar magnetic fields is significant for understanding and predicting solar *** our knowledge of solar magnetic fields largely depends on the photospheric magnetic *** this paper,based on the spherical harmonic expansion of the photospheric magnetic field observed by Wilcox Solar Observatory,we analyze the time series of spherical harmonic coefficients and predict Sunspot Number as well as synoptic maps for Solar Cycle *** find that solar maximum years have complex short-period disturbances,and the time series of coefficient g_(7)~0 is nearly in-phase with Sunspot Number,which may be related to solar meridional *** Long Short-Term Memory networks(LSTM),our prediction suggests that the maximum of Solar Cycle 25 is likely to occur in June 2024 with an error of 8 months,the peak sunspot number may be 166.9±22.6,and the next solar minimum may occur around January *** incorporating Empirical Mode Decomposition,we enhance our forecast of synoptic maps truncated to Order 5,validating their relative *** prediction not only addresses a gap in forecasting the global distribution of the solar magnetic field but also holds potential reference value for forthcoming solar observation plans.

关键词： Solar activity prediction Solar magnetic field Spherical harmonic expansion Long-Short Term Memory(LSTM) Empirical Mode Decomposition(EMD)

Paleo-glacial reconstruction of the Thajwas glacier in the Kashmir Himalaya using 10Be cosmogenic radionuclide dating

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Geoscience Frontiers 2022年第6期13卷 30-40页

作者： Omar Jaan Paul Shakil Ahmad Romshoo Reyaz Ahmad Dar Pankaj Kumar Soumya Prakash Dhal Sundeep Chopra Department of Earth Sciences University of KashmirSrinagarIndia Islamic University of Science and Technology(IUST) KashmirIndia Inter-University Accelerator centre(IUAC) New DelhiIndia Department of geoinformatics University of KashmirSrinagarIndia

Quantitative glacial chronologies of past glaciations are sparse in the Himalaya, and mostly absent in the Kashmir Himalaya. We used cosmogenicBe exposure dating, and geomorphological mapping to reconstruct glacial advances of the Thajwas Glacier(TG) in the Great Himalayan Range of the Kashmir Himalaya. FromBe exposure dating of ten moraine boulders, four glacial stages with ages ~20.77 ±2.28 ka, ~11.46 ± 1.69 ka, ~9.12 ± 1.39 ka and ~4.19 ± 0.78 ka, were identified. The reconstructed cosmogenic radionuclide ages confirmed the global Last Glacial Maximum(g LGM), Younger Dryas, Early Holocene, and Neoglaciation episodes. As per area and volume change analyses, the TG has lost 51.1 km~2 of its area and a volume of 2.64 km~3 during the last 20.77 ± 2.28 ka. Overall, the results suggested that the TG has lost 64% of area and 73% of volume from the Last glacial maximum to Neoglaciation and about 85.74% and 87.67% of area and volume, respectively, from Neoglaciation to the present day. The equilibrium line altitude of the TG fluctuated from 4238 m a.s.l present to3365 m a.s.l during the g LGM(20.77 ± 2.28 ka). The significant cooling induced by a drop in mean ambient temperature resulted in a positive mass balance of the TG during the g LGM. Subsequently the melting accelerated due to the continuing rise of the global ambient temperature. Paleo-glacial history reconstruction of the Kashmir Himalaya, with its specific geomorphic and climatic setting, would help close the information gap about the chronology of past regional glacial episodes.

关键词： Glacier reconstruction Cosmogenic 10Be gLGM Kashmir Himalaya Equilibrium Line Altitude