Physical Geography最新文献_第9页

Critical transition of incising gravel channel to evacuate alluvial lateral supply 切入砾石通道以排出冲积物侧向供应的临界过渡

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-05-11 DOI: 10.1080/02723646.2021.1923368

Santiago Cataño-Álvarez

{"title":"Critical transition of incising gravel channel to evacuate alluvial lateral supply","authors":"Santiago Cataño-Álvarez","doi":"10.1080/02723646.2021.1923368","DOIUrl":"https://doi.org/10.1080/02723646.2021.1923368","url":null,"abstract":"ABSTRACT Incising gravel channels respond with a robust critical transition to the lateral alluvial supply. Previous experiments have studied how supply affects bedload transport, but I studied a setup with converging banks, where the supply–transport relation implies feedback. While increasing flows, a short range of transitional flows showed sharp increase of bedload, accompanied by channel response via longitudinal homogenization (connectivity) and maximum sediment storage. To slightly vary initial bed mixing (channel history), I repeated the experiments three times, which validated the robustness of the transition. This transition synchronized hydraulics and transport along the channel, leading to a wetted width consistent with downstream hydraulic geometry that allowed a critical sediment evacuation with minimum energy and bed alteration. For flows higher than the transitional, longitudinal connectivity persisted, as most of the landslide material was redistributed by fluvial action. Finally, the largest flows dissipated energy excess via coarsening and channel migration, akin to non-incising rivers with floodplain. A conceptual model of the geomorphic cycle of gravel river reaches might contain the proposed critical transition, but only if this transition proves to be robust to bank cohesion and to spatial and temporal size of the experimental setup.","PeriodicalId":54618,"journal":{"name":"Physical Geography","volume":"44 1","pages":"1 - 30"},"PeriodicalIF":1.6,"publicationDate":"2021-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/02723646.2021.1923368","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43222193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessing biological soil crusts as agents of Ca–Mg silicate dissolution and CO2 sequestration 评价生物土壤结皮对钙镁硅酸盐溶解和二氧化碳固存的作用

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-05-04 DOI: 10.1080/02723646.2021.1919379

R. Dorn

引用次数: 1

Morpho-tectonic assessment of Central Northern escarpment of Peninsular India, based on tectonically sensitive geomorphic indices 基于构造敏感地貌指数的印度半岛中北部断崖形态-构造评价

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-04-14 DOI: 10.1080/02723646.2021.1899478

S. Yadav, Sudhir Kumar Singh

{"title":"Morpho-tectonic assessment of Central Northern escarpment of Peninsular India, based on tectonically sensitive geomorphic indices","authors":"S. Yadav, Sudhir Kumar Singh","doi":"10.1080/02723646.2021.1899478","DOIUrl":"https://doi.org/10.1080/02723646.2021.1899478","url":null,"abstract":"ABSTRACT The morpho-tectonic characteristics of the study area were evaluated due to paleo-tectonic significance. The Upper Tons Basin is associated with the Ganga river system, originated over the fracture zones produced after the collision of Indian and Eurasian plates; hence, the study region has its tectonic importance with small-scale tectonic deformation. The relief, drainage and tectonic characteristics are analyzed by using digital elevation model and topographical maps, geomorphic indices, lineaments and transverse profiles. Result reveals that two-third areas are in declining from mature stage (H I < 0.50) or monadnock phase (H I < 0.40). The value of basin asymmetry factor is suggesting right-side tilting of the trunk stream due to the tributaries of the Tons river originating over the Bhander uplands being longer. Further, the comparison of the stream length gradient with normalized stream length gradient shows delineating tectonically anomalous regions, and the anomalous points are addressed in the longitudinal profiles. The scarps fronts of the plateau are more sinuous and highly eroded, while the straight Kaimur fronts indicate relatively sensitive fronts. The relative tectonic activity index helps to evaluate the potential tectonic activity of a drainage basin and drainage network developed over the tectonically pre-designed valley.","PeriodicalId":54618,"journal":{"name":"Physical Geography","volume":"43 1","pages":"753 - 783"},"PeriodicalIF":1.6,"publicationDate":"2021-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/02723646.2021.1899478","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49005433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Assessment and simulation of water transfer for the megacity Istanbul 特大城市伊斯坦布尔的调水评估与模拟

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-04-02 DOI: 10.1080/02723646.2021.1904698

S. Burak, A. Bilge, Duygu Ülker

引用次数: 6

Interactions among hydro-aeolian processes and micro-geomorphology stimulate hot spots of sediment carbon source and sink within a coppice dune system 水文风成过程与微地貌的相互作用刺激了森林沙丘系统中沉积物碳源和碳汇的热点

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-03-31 DOI: 10.1080/02723646.2021.1905594

N. Mohseni, S. Hosseinzadeh

{"title":"Interactions among hydro-aeolian processes and micro-geomorphology stimulate hot spots of sediment carbon source and sink within a coppice dune system","authors":"N. Mohseni, S. Hosseinzadeh","doi":"10.1080/02723646.2021.1905594","DOIUrl":"https://doi.org/10.1080/02723646.2021.1905594","url":null,"abstract":"ABSTRACT We evaluated the impacts of the interactions among hydro-aeolian processes and micro-geomorphology on mechanisms controlling the sediment carbon source and sink within a coppice dune. The sediment sampling process was performed within different positions of each dune. Sediment grain size distribution, geometric mean diameter, mean weight diameter, labile SOC, CO2 flux, and C mineralization ratio were measured. The finest sediments were observed on the dune edge. The labile SOC and CO2 flux rate showed an increasing trend in the edge, windward, and top positions. However, the C mineralization ratio decreased only in the dune edge. A significant increase of clay fractions at the dune edge can result from the horizontal sediment transport by runoff from the interdune area to the dune. The SOC could bond with clay fractions to contribute toward the formation of soil aggregation, causing less vulnerability of SOC to microbial respiration. A significant increase of sand fractions, transported by the aeolian process, on the top and windward positions could not protect SOC against decomposition. The interactions among hydro-aeolian processes and micro-geomorphology could encourage the hot spots of sediment carbon reservoirs within the dryland landforms that have a significant proportion in the exchange of carbon to the atmosphere.","PeriodicalId":54618,"journal":{"name":"Physical Geography","volume":"43 1","pages":"487 - 502"},"PeriodicalIF":1.6,"publicationDate":"2021-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/02723646.2021.1905594","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42688932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Alluvial fans of Trans-Himalayan cold desert (Pin valley, India): quantitative morphology and controlling factors 跨喜马拉雅寒冷沙漠冲积扇（印度平谷）：数量形态和控制因素

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-03-31 DOI: 10.1080/02723646.2021.1907883

Amit Shoshta, B. S. Marh

{"title":"Alluvial fans of Trans-Himalayan cold desert (Pin valley, India): quantitative morphology and controlling factors","authors":"Amit Shoshta, B. S. Marh","doi":"10.1080/02723646.2021.1907883","DOIUrl":"https://doi.org/10.1080/02723646.2021.1907883","url":null,"abstract":"ABSTRACT Pin valley is an ideal area for alluvial fans’ development. Being least disturbed and devoid of vegetation, fans of this area provide exquisite information and extraordinary opportunity to understand different factors that affect their morphology. Despite aforesaid advantages these fans are hitherto not studied. Thus, the present study is an attempt to understand the morphology of these fans and explore factors affecting fan morphology, primarily through morphometry. Data were derived from various satellite imageries, topographical sheets, DEM and field observations. Various parameters of 51 fans and of their basins were measured and relationships among different parameters were examined. The results of the study are generally comparable to literature though these fans are much steeper than their counterparts in similar environmental settings. Multi-proxy approach was used to explore controlling factors. Fan Conicality Index (FCI) and sweep angle of fan (SA ) suggest confinement imposed by surrounding environment has considerably reduced the size of these fans. Further, valley-floor width to height ratio (Vf ), feeder channel and geological group-wise analyses reveal that active tectonic attitude, order of feeder channel, lithology and characteristics of contributing basin along with associated depositional processes exercise significant control on morphology of these fans.","PeriodicalId":54618,"journal":{"name":"Physical Geography","volume":"44 1","pages":"136 - 161"},"PeriodicalIF":1.6,"publicationDate":"2021-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/02723646.2021.1907883","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43625190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Depression morphology of Bayan Lake, Zavkhan province, Western Mongolia: implications for the origin of lake depression in Mongolia 蒙古西部扎夫汗省巴彦湖凹陷形态：对蒙古湖凹陷成因的启示

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-03-23 DOI: 10.1080/02723646.2021.1899477

Altanbold Enkhbold, U. Khukhuudei, T. Kusky, B. Tsermaa, Dash Doljin

引用次数: 5

Landslide susceptibility analysis based on a semiquantitative method in the sierra-costa region, michoacán, mexico 基于半定量方法的墨西哥塞拉-科斯塔地区滑坡易感性分析michoacán

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-03-23 DOI: 10.1080/02723646.2021.1899476

Karla Aurora De La Peña Guillen, M. Mendoza, J. L. Macías, Berenice Solís‐Castillo

{"title":"Landslide susceptibility analysis based on a semiquantitative method in the sierra-costa region, michoacán, mexico","authors":"Karla Aurora De La Peña Guillen, M. Mendoza, J. L. Macías, Berenice Solís‐Castillo","doi":"10.1080/02723646.2021.1899476","DOIUrl":"https://doi.org/10.1080/02723646.2021.1899476","url":null,"abstract":"ABSTRACT Landslides are one of the most common and destructive natural hazards in the world. The Sierra-Costa region in the southwestern part of the Michoacán state, Mexico, is prone to landslides because of its physiography, geology, and climate. In particular, the area is prone to shallow landslides in the weathered rock that is triggered by heavy rainfall. Here, we present a susceptibility model for this hazard that is based on an analytical hierarchy process (AHP). To assess landslide susceptibility, we designed maps of different parameters (lithology, distance to faults, slope gradient, slope aspect, geoforms, soil type, distance to rivers, and land cover). The landslide susceptibility map includes five classes: nullnull, low, moderate, high, and very high susceptibility. About 5% of the area is categorized as having null landslide susceptibility class; 18% is low susceptibility, 28% moderate susceptibility, 29% high susceptibility, and 20% very high susceptibility. The very high susceptibility areas are dominantly underlain by limestone and weathered granite and are near faults. We evaluated the precision of the model using the receiver operating characteristic (ROC) curve method. The susceptibility model represents the first step in understanding the distribution of landslides in the Sierra-Costa region.","PeriodicalId":54618,"journal":{"name":"Physical Geography","volume":"43 1","pages":"463 - 486"},"PeriodicalIF":1.6,"publicationDate":"2021-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/02723646.2021.1899476","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48358470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Preliminary observations of nivation processes, Cathedral Massif, Northwestern British Columbia, Canada 雪化过程的初步观测，加拿大不列颠哥伦比亚省西北部大教堂地块

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-03-19 DOI: 10.1080/02723646.2021.1893142

Raven J. Mitchell, F. Nelson, K. Nyland

{"title":"Preliminary observations of nivation processes, Cathedral Massif, Northwestern British Columbia, Canada","authors":"Raven J. Mitchell, F. Nelson, K. Nyland","doi":"10.1080/02723646.2021.1893142","DOIUrl":"https://doi.org/10.1080/02723646.2021.1893142","url":null,"abstract":"ABSTRACT Nivation, the suite of weathering and transportation processes attributed to late-lying snowpatches, is linked to the formation of cryoplanation terraces (CTs). CTs resemble giant staircases arranged in repeating sequences of low-gradient treads and steep scarps that extend over hundreds of meters. The nivation hypothesis of CT development has been supported in recent literature examining weathering and erosion trends, but the mechanisms involved in transporting sediment across CT treads remain underinvestigated. Sorted stripes, a type of patterned ground encountered on CT treads, have been linked to efficient snow meltwater flow across low gradients, indicating that these features could be an important component of CT formation. In this study, we use short-term soil thermal and moisture records, particle-size analysis, and apparent thermal diffusivity calculations to examine periglacial processes operating on two incipient CTs. Initial results indicate that: (1) the coarse (boulder and cobble size) portions of sorted stripes function as subsurface channels for sediment transportation across gently sloping CT treads (generally < 12°) by flowing water; (2) hillslope hydrology is an important component of the erosion processes sculpting upland periglacial environments; and (3) late-lying snowbank environments are highly dynamic during warm weather, with large amounts of sediment transported over short periods.","PeriodicalId":54618,"journal":{"name":"Physical Geography","volume":"42 1","pages":"513 - 528"},"PeriodicalIF":1.6,"publicationDate":"2021-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/02723646.2021.1893142","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49563690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Flood variability in the common era: a synthesis of sedimentary records from Europe and North America 共同时代的洪水变化：欧洲和北美沉积记录的综合

IF 1.6 4区地球科学

Physical Geography Pub Date : 2021-02-25 DOI: 10.1080/02723646.2021.1890894

Rachel Lombardi, L. Davis, M. Therrell

{"title":"Flood variability in the common era: a synthesis of sedimentary records from Europe and North America","authors":"Rachel Lombardi, L. Davis, M. Therrell","doi":"10.1080/02723646.2021.1890894","DOIUrl":"https://doi.org/10.1080/02723646.2021.1890894","url":null,"abstract":"ABSTRACT Heavy precipitation events increased over the last century in response to higher atmospheric temperature and associated increases in water vapor content, but little evidence shows that increased heavy precipitation changed flood trends. Short records, containing few extreme flood observations, limit statistical examination of relationships between global temperature, heavy precipitation, and extreme floods. We synthesized European and North American sediment-based paleoflood records extending through at least 900 CE. These records captured flood variability during the warmer Medieval Climate Anomaly (MCA) and cooler Little Ice Age (LIA). Twelve paleoflood chronologies chosen for the analysis suggest an increase in flood frequency since 1000 CE. The largest magnitude floods mostly occurred between 1000 and 1300 CE after peak MCA temperature during a relatively drier overall climate regime. The association found between large magnitude floods during a drier climate may be explained by increased atmospheric water vapor capacity from warmer temperatures that intensified precipitation events. Despite limitations in the number of studies available, extreme flood observations reveal a pattern of large magnitude floods in the late MCA and frequent floods in the LIA. Therefore, temperature–precipitation relationships may influence flood variability, and flood magnitude will likely become more extreme as global temperatures rise.","PeriodicalId":54618,"journal":{"name":"Physical Geography","volume":"44 1","pages":"121 - 135"},"PeriodicalIF":1.6,"publicationDate":"2021-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/02723646.2021.1890894","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43658139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4