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International Journal of Digital Earth 2011年第3期4卷 258-270页

作者： R.V.Sheeja Sabu Joseph D.S.Jaya R.S.Baiju kerala state Remote Sensing and Environment Centre VikasbhavanThiruvananthapuram 695033KeralaIndia Department of Environmental sciences University of KeralaKariyavattomThiruvananthapuramKeralaIndia Centre for Earth science Studies(CESS) ThiruvananthapuramKeralaIndia

Land use and land cover change,perhaps the most significant anthropogenic disturbance to the environment,mainly due to rapid urbanization/industrialization and large scale agricultural *** this paper,an attempt has been made to appraise land use/land cover changes over a century(19142007)in the Neyyar River Basin(L56 km;Area483.4 km2)in southern keralaa biodiversity hot spot in Peninsular *** this study,digital remote sensing data of the Indian Remote Sensing satellite series I-D(LISS III,20062007)on 1:50,000 scale,Survey of India(SOI)toposheet of 1914(1:63,360)and 1967(1:50,000)have been utilized to map various land use/land cover *** of different periods have been registered and resampled to similar geographic coordinates using ERDAS Imagine *** most notable changes include decreases in areas of paddy cultivation,mixed crops,scrub lands and evergreen forests,and increases in built-up areas,rubber plantations,dense mixed forests,and water ***,large scale exploitation of flood plain mud and river sand have reached menacing proportions leading to bank caving and cut offs at channel *** of land and water resources forms an important aspect of ecosystem management in the basin.

关键词： remote sensing GIS land use/land cover Neyyar basin kerala

Applicability of SRTM data for landform characterisation and geomorphometry: a comparison with contour-derived parameters

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International Journal of Digital Earth 2011年第5期4卷 387-401页

作者： V.Prasannakumar RShiny NGeetha HVijith Centre for Geoinformation science and Technology University of KeralaKariavattomThiruvananthapuramKerala 695581India

Geomorphologic and hydrologic research heavily depends on digital elevation models(DEM)which are currently being prepared from digital *** present study examines the use and applicability of freely available global elevation data source(3 arc seconds finished Shuttle Radar Topography Mission(SRTM))in landform characterisation,geomorphometry,river basin studies and other allied scientific applications in comparison with contour elevation data derived from the surveyed topographical *** relief data extracted from a conventionally digitised geo-information science dataset of topographic contours(1:50,000)are compared with the SRTM-DEM and the variations are *** automated geomorphometric and landform parameters derived from the contour DEM and the computed statistical properties of those parameters have substantial agreement with the same parameters derived from the *** the same time,localised variations also exist in some spatial *** landscape analysis outputs from the SRTM-DEM suggest the wide acceptability and applicability of the freely available SRTM data source,especially in the regional scale applications related to hydrological modelling,terrain characterisation,disaster management and land degradation studies.

关键词： geomorphometry landform characterisation SRTM wetness index terrain position index

Biomass and carbon stocks in mangrove ecosystems of kerala,southwest coast of India

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Ecological Processes 2020年第1期9卷 355-363页

作者： K.M.Harishma S.Sandeep V.B.Sreekumar Department of Forest Botany Kerala Forest Research InstitutePeechiKerala 680653India Department of Soil science Kerala Forest Research InstitutePeechiKerala 680653India

Background:Mangroves are important tropical carbon sinks,and their role in mitigating climate change is well documented across the ***,the ecosystem carbon stocks in the mangroves of India have not been studied *** from this region is very limited for providing sufficient insights and authentic evaluation of carbon stocks on a regional *** this study,we evaluated the ecosystem carbon stock and its spatial variation in mangroves of kerala,southwest coast of ***:The mean biomass stored in mangrove vegetation of kerala is 117.11±1.02 t/ha(ABG=80.22±0.80,BGB=36.89±0.23 t/ha).Six mangrove species were found distributed in the study *** the different species,Avicennia marina had the highest biomass(162.18 t/ha)and least biomass was observed in Sonneratia alba(0.61 t/ha).The mean ecosystem carbon stock of mangrove systems in kerala was estimated to be 139.82 t/ha,equivalent to 513.13 t CO2 e/ha with the vegetation and soil storing 58.56 t C/ha and 81.26 t C/ha ***:The present study reveals that kerala mangroves store sizable volume of carbon and therefore need to be preserved and managed sustainably,to retain along with the increase in carbon *** features the need of broadening mangrove cover as well as restoring deteriorated land in the past 50 *** mangrove forests in this region are protected by the kerala Forest Department,they have been frequently facing illegal encroachment,prawn cultivation,and coastal erosion.

关键词： Mangrove ecosystem Biomass Aboveground carbon Belowground carbon Ecosystem carbon stock

Sensitivity of digital elevation models:The scenario from two tropical mountain river basins of the Western Ghats,India

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Geoscience Frontiers 2014年第6期5卷 893-909页

作者： Jobin Thomas Sabu Joseph K.P.Thrivikramji K.S.Arunkumar Inter University Centre for Geospatial Information science and Technology University of KeralaThiruvananthapuramKeralaIndia Department of Environmental sciences University of KeralaThiruvananthapuramKeralaIndia Department of Geology University of KeralaThiruvananthapuramKeralaIndia Department of Geology MES CollegePonnaniMalappuramKeralaIndia

The paper evaluates sensitivity of various spaceborne digital elevation models （DEMs）, viz., Advanced Spaceborne Thermal Emission and Reflection Radiometer （ASTER）, Shuttle Radar Topography Mapping Mission （SRTM） and Global Multi-resolution Terrain Elevation Data 2010 （GMTED）, in comparison with the DEM （TOPO） derived from contour data of 20 m interval of Survey of India topographic sheets of 1 ： 50,000 scale. Several topographic attributes, such as elevation （above mean sea level）, relative relief, slope, aspect, curvature, slope-length and -steepness （LS） factor, terrain ruggedness index （TRI）, topo- graphic wetness index （TWI）, hypsometric integral （lhyp） and drainage network attributes （stream number and stream length） of two tropical mountain river basins, viz. Muthirapuzha River Basin and Pambar River Basin are compared to evaluate the variations. Though the basins are comparable in extent, they differ in respect of terrain characteristics and climate. The result.,; suggest that ASTER and SRTM provide equally reliable representation of topography portrayed by TOP（） and the topographic attributes extracted from the spaceborne DEMs are in agreement with those derived from TOPO. Despite the coarser resolution, SRTM shows relatively higher vertical accuracy （RMSE -- 23 and 20 m respectively in MRB and PRB） compared to ASTER （RMSE - 33 and 24 m） and GMTED （RMSE - 59 and 48 m）. Vertical accuracy of all the spaceborne DEMs is influenced by relief of the terrain as well as type of vegetation. Further, GMTED shows significant deviation for most of the attributes, indicating its inability for mountain-river-basin-scale studies.

关键词： DEM ASTER SRTM GMTEDTropical mountain river basins Western Ghats

Bamboo resources of Sikkim Himalaya: diversity, distribution and utilization

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Journal of Forestry Research 2014年第4期25卷 929-934页

作者： Deo Kumar Tamang Dinesh Dhakal D. G. Shrestha Sikkim state Remote Sensing Application Centre Sikkim State Council of Science and Technology Development Area Gangtok 737101 Sikkim

We recorded 8 genera and over 30 species of bamboo in Sikkim of the reported 23 genera and 125 species in Indi＆ Thirty percent of bamboo species were recorded in tropical forests （0-900 m）, 40% of species in sub-tropical forests （900-1,800 m）, 17% of species in temper- ate forests （1,800-2,700 m）, 9% of species in sub-alpine forests （2,700-3,500 m） and 4% of species in alpine vegetation （3,500-4,500 m）. Bamboo is used for various purposes and its versatility qualifies it to be a multiple-use alternative to timber, food for villagers and for tribal in particular. Bamboo is also equally important to Red Panda （Ailurusful- gens）, the state animal of Sikkim. We develop a list of bamboos occur- ring in Sikkim with their vernacular names, distributions and uses in the Himalayan state. However, more extensive study is required to fully describe the bamboo diversity of the Himalayan state.

关键词： bamboo Dendrocalamus diversity uses Sikkim

ANovel Light Weight CNN Framework Integrated with Marine Predator Optimization for the Assessment of Tear Film-Lipid Layer Patterns

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Computer Modeling in Engineering & sciences 2023年第7期136卷 87-106页

作者： Bejoy Abraham Jesna Mohan Linu Shine Sivakumar Ramachandran Department of Computer science and Engineering College of Engineering MuttatharaThiruvananthapuramKerala695008India Department of Computer science and Engineering Mar Baselios College of Engineering and TechnologyThiruvananthapuramKerala695015India Department of Electronics and Communication Engineering College of Engineering TrivandrumKerala695016India

Tear film,the outermost layer of the eye,is a complex and dynamic structure responsible for tear *** tear film lipid layer is a vital component of the tear film that provides a smooth optical surface for the cornea and wetting the ocular *** eye syndrome(DES)is a symptomatic disease caused by reduced tear production,poor tear quality,or excessive *** diagnosis is a difficult task due to its multifactorial *** of several clinical tests available,the evaluation of the interference patterns of the tear film lipid layer forms a potential tool for DES *** instrument known as Tearscope Plus allows the rapid assessment of the lipid layer.A grading scale composed of five categories is used to classify lipid layer *** reported work proposes the design of an automatic system employing light weight convolutional neural networks(CNN)and nature inspired optimization techniques to assess the tear film lipid layer patterns by interpreting the images acquired with the Tearscope *** designed framework achieves promising results compared with the existing state-of-the-art techniques.

关键词： Dry-eye syndrome tearscope plus tear film deep neural networks

Next Generation Nutrition: Genomic and Molecular Breeding Innovations for Iron and Zinc Biofortification in Rice

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Rice science 2024年第5期31卷 526-544,I0029,I0030页

作者： Kunhikrishnan Hemalatha DHANYALAKSHMI Reshma MOHAN Sasmita BEHERA Uday Chand JHA Debashis MOHARANA Ahalya BEHERA Sini THOMAS Preman Rejitha SOUMYA Rameswar Prasad SAH Radha BEENA Department of Plant Physiology College of AgriculturePadannakkadKerala Agricultural UniversityKerala 671314India Department of Plant Physiology College of AgricultureVellayaniKerala Agricultural UniversityKerala 695522India Crop Improvement Division India Council of Agricultural Research-National Rice Research InstituteOdisha 7530006India Department of Plant Breeding and Genetics Indian Institute of Pulse ResearchKanpur 208024India Department of Plant Physiology College of AgricultureKumarakomKerala Agricultural UniversityKerala 686563India

Global efforts to address malnutrition and hidden hunger, particularly prevalent in low- and middle-income countries, have intensified, with a focus on enhancing the nutritional content of staple crops like rice. Despite serving as a staple for over half of the world's population, rice falls short in meeting daily nutritional requirements, especially for iron(Fe) and zinc(Zn). Genetic resources, such as wild rice species and specific rice varieties, offer promising avenues for enhancing Fe and Zn content. Additionally, molecular breeding approaches have identified key genes and loci associated with Fe and Zn accumulation in rice grains. This review explores the genetic resources and molecular mechanisms underlying Fe and Zn accumulation in rice grains. The functional genomics involved in Fe uptake, transport, and distribution in rice plants have revealed key genes such as OsFRO1, OsIRT1, and OsNAS3. Similarly, genes associated with Zn uptake and translocation, including OsZIP11 and OsNRAMP1, have been identified. Transgenic approaches, leveraging transporter gene families and genome editing technologies, offer promising avenues for enhancing Fe and Zn content in rice grains. Moreover, strategies for reducing phytic acid(PA) content, a known inhibitor of mineral bioavailability, have been explored, including the identification of low-PA mutants and natural variants. The integration of genomic information, including whole-genome resequencing and pan-genome analyses, provides valuable insights into the genetic basis of micronutrient traits and facilitates targeted breeding efforts. Functional genomics studies have elucidated the molecular mechanisms underlying Fe uptake and translocation in rice. Furthermore, transgenic and genome editing techniques have shown promise in enhancing Fe and Zn content in rice grains through the manipulation of key transporter genes. Overall, the integration of multi-omics approaches holds significant promise for addressing global malnutri

关键词： biofortification grain quality iron phytic acid rice zinc

Morphometric aspects of a small tropical mountain river system,the southern Western Ghats,India

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International Journal of Digital Earth 2010年第2期3卷 135-156页

作者： Jobin Thomas Sabu Joseph K.P.Thrivikramaji Department of Environmental sciences University of KeralaThiruvananthapuram 695581KeralaIndia Department of Geology University of KeralaThiruvananthapuram 695581KeralaIndia

The Muthirapuzha watershed(MW)is one among the major tributaries of Periyarthe longest west flowing river in kerala,India.A morphometric analysis was carried out to determine the spatial variations in the drainage characteristics of MW and its 14 fourth order sub-watersheds(SW1SW14)using Survey of India topographic maps and Landsat ETM*** study revealed that the watershed includes a sixth order stream and lower order streams dominate the *** did indicate that rainfall has a significant role in the drainage development whereas structure and relief of rocks dictate the drainage *** asymmetry in the drainage distribution is correlated with the tectonic history of the Munnar plateau in the late Paleocene *** watershed is moderate to well-drained and exhibited a geomorphic maturity in its physiographic *** shape parameters revealed the elongated nature of MW and drainage network development in the ***,the analysis provided significant insight into the terrain *** study strongly brings to light,(a)the tendency of the watershed to soil loss and(b)the hydrological makeup of the subwatersheds,which combined helped to formulate a comprehensive watershed management plan.

关键词： morphometry digital earth Muthirapuzha watershed Western Ghats India

Mercury concentrations in blood and feathers of nestling Bald Eagles in coastal and inland Virginia

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Avian Research 2019年第1期10卷 36-42页

作者： David E.Kramar Bill Carstensen Steve Prisley Jim Campbell Department of Anthropology and Earth science Minnesota State University Moorhead Department of Geography Virginia Tech National council for Air and Stream Improvement

Background:Mercury(Hg) and methylmercury are widely considered significant issues for wildlife,and in particular,piscivorous birds due to their widespread availability and neurotoxic *** a substantial number of studies of Hg contamination of Bald Eagles(Haliaeetus leucocephalus) have been conducted throughout the east coast of the United states,little has been done that directly addresses Hg contamination in Bald Eagles in Virginia,particularly the inland ***:We collected blood and feather samples from nestling Bald Eagles in the coastal plain,piedmont,and western regions of Virginia in an effort to determine which areas of the state were more likely to contain populations showing evidence of Hg *** analyzed the samples for total Hg using a Milestone ***:Samples collected from individuals located in the coastal region exhibited low concentrations of Hg compared to those further inland located on freshwater rivers and *** collected from the inland population exhibited levels in some areas that are approaching what may be considered to be sub-lethal to avian health(blood:mean 0.324 mg/kg,SE = 0.13,range = 0.06-0.97 mg/kg;feather:mean = 8.433 mg/kg,SE = 0.3,range = 3.811-21.14 mg/kg).Conclusions:Even after accounting for known point-sources of Hg,the inland eagle population in Virginia is susceptible to concentrations of Hg that are significantly higher than their coastal ***,several locations besides those currently known to be impacted by point-sources are exhibiting concentrations that are approaching a sub-lethal level.

关键词： Bald Eagle Haliaeetus leucocephalus Mercury Methyl-mercury Virginia

Structural,magnetic and antibacterial properties of manganese-substituted magnetite ferrofluids

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International Journal of Minerals,Metallurgy and Materials 2023年第7期30卷 1417-1426页

作者： Blessy Babukutty Deepalekshmi Ponnamma Swapna S.Nair Jiya Jose Saritha G.Bhat Sabu Thomas Department of Physics Central University of KeralaKasargod 671314India Materials science and Technology Program College of Arts and SciencesQatar UniversityP.O.Box 2713DohaQatar Department of Biotechnology Cochin University of Science and TechnologyKalamasseryKeralaIndia Department of Chemistry Mahatma Gandhi UniversityKottayam 686560KeralaIndia

Manganese-substituted magnetite ferrofluids(FFs)Mnx Fe_(1-x)Fe_(2)O_(4)(x=0–0.8)were prepared in this work through a chemical coprecipitation *** controlled growth of FF nanomaterials for antibacterial activities is challenging,and therefore,very few reports are available on the *** research focuses on stabilizing aqueous FFs with the tetramethylammonium hydroxide surfactant to achieve high *** characterization reveals nanoparticles of 5–11 nm formed by the chemical reaction and nanocrystalline nature,as evident from structural ***-substituted magnetic FFs are analyzed for their structural,functional,and antibacterial performance according to the Mn-substituent *** studies show a high blue shift for Mn^(2+)-substituted Mnx Fe_(1-x)Fe_(2)O_(4)with the theoretical correlation of optical band gaps with the Mn *** superparamagnetic nature of substituted FFs causes zero coercivity and remanence,which consequently influence the particle size,cation distribution,and spin *** structural and functional performance of the FFs is correlated with the antibacterial activity,finally demonstrating the highest inhibition zone formation for Mnx Fe_(1-x)Fe_(2)O_(4)FFs.

关键词： manganese ferrofluids homogeneity antibacterial stability