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Zhang S, Chai R, Hu Y, Joka FR, Wu X, Wang H, Wang X. Unveiling the spatial distribution and transboundary pathways of FMD serotype O in Western China and its bordering countries. PLoS One 2024; 19:e0306746. [PMID: 39150924 PMCID: PMC11329131 DOI: 10.1371/journal.pone.0306746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 06/21/2024] [Indexed: 08/18/2024] Open
Abstract
Foot-and-mouth disease (FMD) is a severe, highly contagious viral disease of livestock that has a significant economic impact on domestic animals and threatens wildlife survival in China and border countries. However, effective surveillance and prevention of this disease is often incomplete and unattainable due to the cost, the great diversity of wildlife hosts, the changing range and dynamics, and the diversity of FMDV. In this study, we used predictive models to reveal the spread and risk of FMD in anticipation of identifying key nodes to control its spread. For the first time, the spatial distribution of FMD serotype O was predicted in western China and border countries using a niche model, which is a combination of eco-geographic, human, topographic, and vegetation variables. The transboundary least-cost pathways (LCPs) model for ungulates in the study area were also calculated. Our study indicates that FMD serotype O survival is seasonal at low altitudes (March and June) and more sensitive to temperature differences at high altitudes. FMD serotype O risk was higher in Central Asian countries and both were highly correlated with the population variables. Ten LCPs were obtained representing Pakistan, Kazakhstan, Kyrgyzstan, and China.
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Affiliation(s)
- Shuang Zhang
- Center of Conservation Medicine & Ecological Safety, Northeast Forestry University, Harbin, Heilongjiang Province, P. R. China
- The Key Laboratory of Wildlife Diseases and Biosecurity Management, Harbin, Heilongjiang Province, P. R. China
| | - Rong Chai
- Center of Conservation Medicine & Ecological Safety, Northeast Forestry University, Harbin, Heilongjiang Province, P. R. China
- The Key Laboratory of Wildlife Diseases and Biosecurity Management, Harbin, Heilongjiang Province, P. R. China
| | - Yezhi Hu
- Center of Conservation Medicine & Ecological Safety, Northeast Forestry University, Harbin, Heilongjiang Province, P. R. China
- The Key Laboratory of Wildlife Diseases and Biosecurity Management, Harbin, Heilongjiang Province, P. R. China
| | | | - Xiaodong Wu
- China Animal Health and Epidemiology Center, Qingdao, Shandong Province, P. R. China
| | - Haoning Wang
- School of Geography and Tourism, Harbin University, Harbin, Heilongjiang Province, P. R. China
- Heilongjiang Cold Region Wetland Ecology and Environment Research Key Laboratory, Harbin University, Harbin, Heilongjiang Province, P. R. China
| | - Xiaolong Wang
- Center of Conservation Medicine & Ecological Safety, Northeast Forestry University, Harbin, Heilongjiang Province, P. R. China
- The Key Laboratory of Wildlife Diseases and Biosecurity Management, Harbin, Heilongjiang Province, P. R. China
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Density Pattern of Flare-Horned Markhor (Capra falconeri) in Northern Pakistan. SUSTAINABILITY 2022. [DOI: 10.3390/su14159567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Wild ungulates play vital roles in maintaining a balanced ecosystem through herbivory and are also an important determinant of carnivores’ density. The flare-horned markhor (Capra falconeri) is a threatened wild goat distributed across the mountain ranges of Pakistan, India, Afghanistan, Russia, Turkmenistan, Uzbekistan, and Tajikistan. The remote terrain and fragmented population limit our understanding of the population ecology of markhor, though knowledge of the target species population is vital for making informed management decisions. Therefore, the current study was designed to determine the markhor population across their range in Northern Pakistan and to evaluate the efforts made by the government and non-government organizations for the conservation of markhor. Double-observer surveys were conducted during 2019–2021 in nine major watersheds of Khyber Pakhtunkhwa and Gilgit-Baltistan covering an area of 4664 km2. Secondary data were collected for unassessed areas to gain a holistic overview of the markhor population and density in the region. Results revealed a markhor population of 7579, with a density of 0.30 animals per km2 in Northern Pakistan. Our analysis of the double-observer data through the Bayesian behavioral capture–recapture model estimated a population of 5993 individuals (95% CI) of markhor across nine study sites, with a density of 1.28 animals per km2. A review of secondary data revealed that a population of about 1586 was present in the un-surveyed area (20,033.33 km2), with a density of 0.08 per km2. A total of 146 groups of markhor were counted, with a mean group size of 23 (3–58) individuals. There were 109 males and 108 young per 100 females in the population. Among 1936 recorded males, Class I males accounted for 27.74%, followed by Class II (26.45%), Class IV (trophy-size) (23.40%), and Class III (22.42%). The overall detection probability was recorded as 0.87 and 0.68 for the first observer and second observer, respectively. Compared with the past reports, the population of markhor in Northern Pakistan appears to be increasing, particularly in protected areas (PAs) such as national parks and community-controlled hunting areas (CCHAs). Conservation programs, notably trophy hunting and PA networks, appear to be vital in sustaining markhor populations in parts of the species range. We recommend expansion in such programs in the markhor range in order to maintain a viable population of this majestic wild goat in the region.
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Gao S, Xu G, Zeng Z, Lv J, Huang L, Wang H, Wang X. Transboundary spread of peste des petits ruminants virus in western China: A prediction model. PLoS One 2021; 16:e0257898. [PMID: 34555121 PMCID: PMC8459964 DOI: 10.1371/journal.pone.0257898] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 09/13/2021] [Indexed: 11/23/2022] Open
Abstract
In pan Pamir Plateau countries, Peste des petits ruminants (PPR) has brought huge losses to the livestock industry and threaten the endangered wildlife. In unknown regions, revealing PPRV transmission among countries is the premise of effective prevention and control, therefore calls for quantified monitoring on disease communication among countries. In this paper, a MaxEnt model was built for the first time to predict the PPR risk within the research area. The least cost path (LCP) for PPR transboundary communication were calculated and referred to as the maximum available paths (MAP). The results show that there are many places with high-risk in the research area, and the domestic risk in China is lower than that in foreign countries and is mainly determined by human activities. Five LCPs representing corridors among Kazakhstan, Tajikistan, Pakistan, India and China were obtained. This study proves for the first time that there is the possibility of cross-border transmission of diseases by wild and domestic animals. In the future, it will play an important role in monitoring the PPR epidemic and blocking-up its cross-border transmission.
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Affiliation(s)
- Shan Gao
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin, Heilongjiang province, P. R. China
- Key Laboratory of Wildlife diseases and Biosecurity Management of Heilongjiang Province, Harbin, Heilongjiang province, The People’s Republic of China
| | - GuoYong Xu
- The Second Geomatics Cartography Institute of National Administration of Ministry of Natural Resources, Harbin, Heilongjiang province, P. R. China
| | - Zan Zeng
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin, Heilongjiang province, P. R. China
- Key Laboratory of Wildlife diseases and Biosecurity Management of Heilongjiang Province, Harbin, Heilongjiang province, The People’s Republic of China
| | - JiaNing Lv
- Key Laboratory of Wildlife diseases and Biosecurity Management of Heilongjiang Province, Harbin, Heilongjiang province, The People’s Republic of China
| | - LiYa Huang
- Changbai Mountain Academy of Sciences, Antu, Jilin province, P. R. China
| | - HaoNing Wang
- School of Geography and Tourism, Harbin University, Harbin, Heilongjiang province, The People’s Republic of China
| | - XiaoLong Wang
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin, Heilongjiang province, P. R. China
- Key Laboratory of Wildlife diseases and Biosecurity Management of Heilongjiang Province, Harbin, Heilongjiang province, The People’s Republic of China
- * E-mail:
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Leal-Sáenz A, Waring KM, Álvarez-Zagoya R, Hernández-Díaz JC, López-Sánchez CA, Martínez-Guerrero JH, Wehenkel C. Assessment and Models of Insect Damage to Cones and Seeds of Pinus strobiformis in the Sierra Madre Occidental, Mexico. FRONTIERS IN PLANT SCIENCE 2021; 12:628795. [PMID: 33995433 PMCID: PMC8116514 DOI: 10.3389/fpls.2021.628795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 03/30/2021] [Indexed: 05/31/2023]
Abstract
Insect damage to cones and seeds has a strong impact on the regeneration of conifer forest ecosystems, with broader implications for ecological and economic services. Lack of control of insect populations can lead to important economic and environmental losses. Pinus strobiformis is the most widespread of the white pines in Mexico and is widely distributed throughout the mountains of northern Mexico. Relatively few studies have examined insect damage to the cones and seeds of these pines, especially in Mexico. In this study, we therefore analyzed insect damage to cones and seeds of P. strobiformis in Mexico by using X-ray and stereomicroscopic analysis. The specific objectives of the study were (a) to characterize insect damage by measuring external and internal cone traits, (b) to assess the health of seeds and cones of P. strobiformis in the Sierra Madre Occidental, Mexico, and (c) to estimate the relative importance of the effects of different environmental variables on cone and seed damage caused by insects. We found that 80% of P. strobiformis seeds and 100% of the tree populations studied had damage caused by insects. Most seeds were affected by Leptoglossus occidentalis, Tetyra bipunctata, Megastigmus albifrons, and the Lepidoptera complex (which includes Apolychrosis synchysis, Cydia latisigna, Eucosma bobana, and Dioryctria abietivorella). The cones of all tree populations were affected by some type of insect damage, with Lepidoptera causing most of the damage (72%), followed by Conophthorus ponderosae (15%), the hemipteran L. occidentalis (7%), and the wasp M. albifrons (6%). The proportion of incomplete seeds in P. strobiformis at the tree level, cone damage by M. albifrons and seed damage in L. occidentalis were associated with various climate and soil variables and with crown dieback. Thus, cone and seed insect damage can be severe and potentially impact seed production in P. strobiformis and the reforestation potential of the species. The study findings will enable managers to better identify insects that cause damage to cone and seeds. In addition, identification of factors associated with damage may be useful for predicting the levels of insect predation on seeds and cones.
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Affiliation(s)
- Alejandro Leal-Sáenz
- Programa Institucional de Doctorado en Ciencias Agropecuarias y Forestales, Universidad Juárez del Estado de Durango, Durango, Mexico
| | - Kristen M. Waring
- School of Forestry, Northern Arizona University, Flagstaff, AZ, United States
| | | | - José Ciro Hernández-Díaz
- Instituto de Silvicultura e Industria de la Madera, Universidad Juárez del Estado de Durango, Durango, Mexico
| | - Carlos A. López-Sánchez
- SMartForest Group, Department of Biology of Organisms and Systems, Mieres Polytechnic School, University of Oviedo, Mieres, Spain
| | | | - Christian Wehenkel
- Instituto de Silvicultura e Industria de la Madera, Universidad Juárez del Estado de Durango, Durango, Mexico
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Leal-Sáenz A, Waring KM, Menon M, Cushman SA, Eckert A, Flores-Rentería L, Hernández-Díaz JC, López-Sánchez CA, Martínez-Guerrero JH, Wehenkel C. Morphological Differences in Pinus strobiformis Across Latitudinal and Elevational Gradients. FRONTIERS IN PLANT SCIENCE 2020; 11:559697. [PMID: 33193485 PMCID: PMC7642095 DOI: 10.3389/fpls.2020.559697] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 09/28/2020] [Indexed: 06/02/2023]
Abstract
The phenotype of trees is determined by the relationships and interactions among genetic and environmental influences. Understanding the patterns and processes that are responsible for phenotypic variation is facilitated by studying the relationships between phenotype and the environment among many individuals across broad ecological and climatic gradients. We used Pinus strobiformis, which has a wide latitudinal distribution, as a model species to: (a) estimate the relative importance of different environmental factors in predicting these morphological traits and (b) characterize the spatial patterns of standing phenotypic variation of cone and seed traits across the species' range. A large portion of the total variation in morphological characteristics was explained by ecological, climatic and geographical variables (54.7% collectively). The three climate, vegetation and geographical variable groups, each had similar total ability to explain morphological variation (43.4%, 43.8%, 51.5%, respectively), while the topographical variable group had somewhat lower total explanatory power (36.9%). The largest component of explained variance (33.6%) was the four-way interaction of all variable sets, suggesting that there is strong covariation in environmental, climate and geographical variables in their relationship to morphological traits of southwest white pine across its range. The regression results showed that populations in more humid and warmer climates expressed greater cone length and seed size. This may in part facilitate populations of P. strobiformis in warmer and wetter portions of its range growing in dense, shady forest stands, because larger seeds provide greater resources to germinants at the time of germination. Our models provide accurate predictions of morphological traits and important insights regarding the factors that contribute to their expression. Our results indicate that managers should be conservative during reforestation efforts to ensure match between ecotypic variation in seed source populations. However, we also note that given projected large range shift due to climate change, managers will have to balance the match between current ecotypic variation and expected range shift and changes in local adaptive optima under future climate conditions.
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Affiliation(s)
- Alejandro Leal-Sáenz
- Programa Institucional de Doctorado en Ciencias Agropecuarias y Forestales, Universidad Juárez del Estado de Durango, Durango, Mexico
| | - Kristen M. Waring
- School of Forestry, Northern Arizona University, Flagstaff, AZ, United States
| | - Mitra Menon
- Department of Evolution and Ecology, University of California, Davis, Davis, CA, United States
| | | | - Andrew Eckert
- Department of Biology, Virginia Commonwealth University, Richmond, VA, United States
| | | | - José Ciro Hernández-Díaz
- Instituto de Silvicultura e Industria de la Madera, Universidad Juárez del Estado de Durango, Durango, Mexico
| | - Carlos Antonio López-Sánchez
- Department of Biology of Organisms and Systems, Mieres Polytechnic School, University of Oviedo, Campus Universitario de Mieres, C/Gonzalo Gutiérrez Quirós S/N, Mieres, Spain
| | | | - Christian Wehenkel
- Instituto de Silvicultura e Industria de la Madera, Universidad Juárez del Estado de Durango, Durango, Mexico
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Watts SM, McCarthy TM, Namgail T. Modelling potential habitat for snow leopards (Panthera uncia) in Ladakh, India. PLoS One 2019; 14:e0211509. [PMID: 30695083 PMCID: PMC6350993 DOI: 10.1371/journal.pone.0211509] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 01/15/2019] [Indexed: 11/22/2022] Open
Abstract
The snow leopard Panthera uncia is an elusive species inhabiting some of the most remote and inaccessible tracts of Central and South Asia. It is difficult to determine its distribution and density pattern, which are crucial for developing conservation strategies. Several techniques for species detection combining camera traps with remote sensing and geographic information systems have been developed to model the habitat of such cryptic and low-density species in challenging terrains. Utilising presence-only data from camera traps and direct observations, alongside six environmental variables (elevation, aspect, ruggedness, distance to water, land cover, and prey habitat suitability), we assessed snow leopard habitat suitability across Ladakh in northern India. This is the first study to model snow leopard distribution both in India and utilising direct observation data. Results suggested that elevation and ruggedness are the two most influential environmental variables for snow leopard habitat suitability, with highly suitable habitat having an elevation range of 2,800 m to 4,600 m and ruggedness of 450 m to 1,800 m. Our habitat suitability map estimated approximately 12% of Ladakh's geographical area (c. 90,000 km2) as highly suitable and 18% as medium suitability. We found that 62.5% of recorded livestock depredation along with over half of all livestock corrals (54%) and homestays (58%) occurred within highly suitable snow leopard habitat. Our habitat suitability model can be used to assist in allocation of conservation resources by targeting construction of livestock corrals to areas of high habitat suitability and promoting ecotourism programs in villages in highly suitable snow leopard habitat.
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Wang M, Blank D, Liu W, Wang Y, Yang W. The group pattern of Marco Polo sheep in the Chinese Pamir plateau. EUR J WILDLIFE RES 2018. [DOI: 10.1007/s10344-018-1235-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Salas EAL, Valdez R, Michel S, Boykin KG. Habitat assessment of Marco Polo sheep ( Ovis ammon polii) in Eastern Tajikistan: Modeling the effects of climate change. Ecol Evol 2018; 8:5124-5138. [PMID: 29876087 PMCID: PMC5980363 DOI: 10.1002/ece3.4103] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 03/26/2018] [Indexed: 11/06/2022] Open
Abstract
Identifying the factors predicting the high-elevation suitable habitats of Central Asian argali wild sheep and how these suitable habitats are affected by the changing climate regimes could help address conservation and management efforts and identify future critical habitat for the species in eastern Tajikistan. This study used environmental niche models (ENMs) to map and compare potential present and future distributions of suitable environmental conditions for Marco Polo argali. Argali occurrence points were collected during field surveys conducted from 2009 to 2016. Our models showed that terrain ruggedness and annual mean temperature had strong correlations on argali distribution. We then used two greenhouse gas concentration trajectories (RCP 4.5 and RCP 8.5) for two future time periods (2050 and 2070) to model the impacts of climate change on Marco Polo argali habitat. Results indicated a decline of suitable habitat with majority of losses observed at lower elevations (3,300-4,300 m). Models that considered all variables (climatic and nonclimatic) predicted losses of present suitable areas of 60.6% (6,928 km2) and 63.2% (7,219 km2) by 2050 and 2070, respectively. Results also showed averaged habitat gains of 46.2% (6,106 km2) at much higher elevations (4,500-6,900 m) and that elevational shifts of habitat use could occur in the future. Our results could provide information for conservation planning for this near threatened species in the region.
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Affiliation(s)
- Eric Ariel L. Salas
- Agricultural Research and Development ProgramCollege of Science and EngineeringCentral State UniversityWilberforceOhio
| | - Raul Valdez
- Department of Fish, Wildlife and Conservation EcologyNew Mexico State UniversityLas CrucesNew Mexico
| | - Stefan Michel
- IUCN Species Survival CommissionCaprinae Specialist GroupKannawurfGermany
| | - Kenneth G. Boykin
- Department of Fish, Wildlife and Conservation EcologyNew Mexico State UniversityLas CrucesNew Mexico
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Escobar-Flores JG, Lopez-Sanchez CA, Sandoval S, Marquez-Linares MA, Wehenkel C. Predicting Pinus monophylla forest cover in the Baja California Desert by remote sensing. PeerJ 2018; 6:e4603. [PMID: 29637026 PMCID: PMC5889705 DOI: 10.7717/peerj.4603] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/21/2018] [Indexed: 11/20/2022] Open
Abstract
The Californian single-leaf pinyon (Pinus monophylla var. californiarum), a subspecies of the single-leaf pinyon (the world's only one-needled pine), inhabits semi-arid zones of the Mojave Desert (southern Nevada and southeastern California, US) and also of northern Baja California (Mexico). This tree is distributed as a relict subspecies, at elevations of between 1,010 and 1,631 m in the geographically isolated arid Sierra La Asamblea, an area characterized by mean annual precipitation levels of between 184 and 288 mm. The aim of this research was (i) to estimate the distribution of P. monophylla var. californiarum in Sierra La Asamblea by using Sentinel-2 images, and (ii) to test and describe the relationship between the distribution of P. monophylla and five topographic and 18 climate variables. We hypothesized that (i) Sentinel-2 images can be used to predict the P. monophylla distribution in the study site due to the finer resolution (×3) and greater number of bands (×2) relative to Landsat-8 data, which is publically available free of charge and has been demonstrated to be useful for estimating forest cover, and (ii) the topographical variables aspect, ruggedness and slope are particularly important because they represent important microhabitat factors that can determine the sites where conifers can become established and persist. An atmospherically corrected a 12-bit Sentinel-2A MSI image with 10 spectral bands in the visible, near infrared, and short-wave infrared light region was used in combination with the normalized differential vegetation index (NDVI). Supervised classification of this image was carried out using a backpropagation-type artificial neural network algorithm. Stepwise multiple linear binominal logistical regression and Random Forest classification including cross validation were used to model the associations between presence/absence of P. monophylla and the five topographical and 18 climate variables. Using supervised classification of Sentinel-2 satellite images, we estimated that P. monophylla covers 6,653 ± 319 ha in the isolated Sierra La Asamblea. The NDVI was one of the variables that contributed most to the prediction and clearly separated the forest cover (NDVI > 0.35) from the other vegetation cover (NDVI < 0.20). Ruggedness was the most influential environmental predictor variable, indicating that the probability of occurrence of P. monophylla was greater than 50% when the degree of ruggedness terrain ruggedness index was greater than 17.5 m. The probability of occurrence of the species decreased when the mean temperature in the warmest month increased from 23.5 to 25.2 °C. Ruggedness is known to create microclimates and provides shade that minimizes evapotranspiration from pines in desert environments. Identification of the P. monophylla stands in Sierra La Asamblea as the most southern populations represents an opportunity for research on climatic tolerance and community responses to climate variability and change.
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Affiliation(s)
- Jonathan G Escobar-Flores
- Centro Interdisciplinario De Investigación para el Desarrollo Integral Regional, Unidad Durango, Instituto Politécnico Nacional, Durango, Durango, México
| | - Carlos A Lopez-Sanchez
- Instituto de Silvicultura e Industria de la Madera, Universidad Juárez del Estado de Durango, Durango, Mexico
| | - Sarahi Sandoval
- CONACYT-Instituto Politécnico Nacional, CIIDIR Unidad Durango, Durango, Durango, México
| | - Marco A Marquez-Linares
- Centro Interdisciplinario De Investigación para el Desarrollo Integral Regional, Unidad Durango, Instituto Politécnico Nacional, Durango, Durango, México
| | - Christian Wehenkel
- Instituto de Silvicultura e Industria de la Madera, Universidad Juárez del Estado de Durango, Durango, Mexico
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Abdelaziz R, Abd El-Rahman Y, Wilhelm S. Landsat-8 data for chromite prospecting in the Logar Massif, Afghanistan. Heliyon 2018; 4:e00542. [PMID: 29560456 PMCID: PMC5857628 DOI: 10.1016/j.heliyon.2018.e00542] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Revised: 12/17/2017] [Accepted: 02/08/2018] [Indexed: 11/18/2022] Open
Abstract
Chromite is widely distributed in the east and southeast of Afghanistan, especially in Logar Province. Chromite mineralization is podiform-type and is hosted in the stratigraphically lowest ultramafic rocks of the Logar Ophiolite Complex. This ophiolite complex represents a remnant of an early Cretaceous oceanic crust that was thrusted over a late Permian to Mid-Jurassic platform-type sequence of the Kabul Terrane during the Himalayan Orogeny. The ultramafic rocks are composed mainly of dunite and harzburgite, which are variably serpentinized. Chromite mineralization of the Logar area ranges from massive chromitite pods to disseminated chromite crystals in the ultramafic rocks. Microscopically, the chromite exhibits granular texture and is generally fresh; however, some magnetite and/or ferritchromite are formed along the fractures of some chromite grains. The primary interstitial silicate minerals of the massive chromite and the silicate minerals surrounding the disseminated chromite grains are completely altered to serpentine along with some chlorite. Thus, serpentinite is most likely the host of the chromite in the Logar Province. The main aim of this study is discriminate serpentine using the Landsat 8 Operational Land Imager (OLI). The serpentinite of the Logar Province is separated by the combination of bands, principal components, band ratios, and supervised classification techniques. Using Landsat 8 and supervised classification with maximum likelihood classification as a tool for mineral exploration improve lithological mapping in the Logar Valley area.
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Affiliation(s)
- Ramadan Abdelaziz
- College of Engineering, A'Sharqiyah University, Oman
- TU Bergakademie Freiberg, Freiberg, Germany
- Corresponding author.
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