Typhoon and weathering processes on particles export to the ocean from a small river on the oceanic island of Taiwan

2020 ◽  
Author(s):  
Wei-rong Chen ◽  
IJy Hsieh ◽  
Kelly Lien ◽  
Saulwood Lin
Keyword(s):  
Chemical Weathering ◽  
Extreme Event ◽  
Weather Condition ◽  
Oceanic Island ◽  
Small River ◽  
Small Rivers ◽  
Chemical Analyses ◽  
Discharge Data ◽  
Physical Weathering ◽  
Dissolved Components

<p>Huge quantity of terrigenous particles was exported from oceanic island small rivers in delivering to the ocean (Dadson et al., 2003; Milliman and Syvitsky, 1992).  Quantity of river particles entering the ocean could be related to river basin area, elevation, erosion rate, and seismic activity.  However, limited data are available regarding differences between physical and chemical weathering on erosion and their effects on particles export from oceanic type of small rivers nor data on extreme event, the typhoon, and its effect on weathering at this setting. Here we report and quantify particles as well as dissolved materials export from an oceanic small river, the Lanyang River at the northeastern Taiwan, during typhoon period and those under normal weather condition.  Our objectives are to quantify river particles and dissolved components export during normal and typhoon period; to understand factors controlling their variations; to compare efficiency of chemical and physical weathering under extreme weather condition and those at normal condition.  River particles and dissolved components were sampled monthly and during typhoons at every four hours frequency and filtered, weighted for particle concentrations as well as chemical analyses of particle and dissolved compositions in lab.  Chemical analyses include solid and dissolve silica, aluminum, iron, sodium, calcium, magnesium, and potassium as well as dissolved chloride, sulfate, and alkalinity. River discharge data were from Taiwan Water Resources Agency and precipitation data from Taiwan Central Weather Bureau.</p><p> </p><p>Our results demonstrated that typhoon is the primary mechanism in driving concentration variations of both dissolved phases and solid components in the study river.  Huge amount of precipitation flushed into river during typhoon, resulting in rapid dilution of dissolved components as well as rapid increase of suspended particles concentration in reaching hyperpycnal level.  During the period of rapid increase of particles in the river, shift of types of particles as well as dissolve components were observed.  TDS (total dissolved solid) represent a small portion of the materials export to the ocean.  TSM (total suspended matter) flushed out of river during typhoon represent a major fraction (85%) of the annual total particles, however, the amount of particles for each typhoon varied significantly (from ~10 to ~45%). </p>

scholarly journals Assessment of medium and small river health based on macroinvertebrates habitat suitability curves: a case study in a tributary of Yangtze River, China

Water Policy ◽  
2020 ◽  
Vol 22 (4) ◽  
pp. 602-621
Author(s):  
Yifan Su ◽  
Weiming Li ◽  
Liu Liu ◽  
Jinjing Li ◽  
Xuyang Sun ◽  
...  
Keyword(s):  
Health Status ◽  
Habitat Suitability ◽  
Yangtze River ◽  
Evaluation Method ◽  
Pearson Correlation ◽  
Small River ◽  
Low Flow ◽  
Small Rivers ◽  
Physical Parameters ◽  
River Health

Abstract The health of medium and small river ecosystems is threatened by increasing hydropower development and human activities. How to properly diagnose rivers has become a global concern. As a well-accepted theory, the aquatic organism density can be an indicator of river health. A new river health assessment method based on macroinvertebrates habitat suitability curves (M-HSC) was proposed. In this study, the health of Qiaobian River (QBR), a tributary of Yangtze River, China was evaluated by investigating the distribution of macroinvertebrates, chemical and physical parameters during winter 2018 (low flow season) and summer 2019 (high flow season). Based on habitat suitability of dominant macroinvertebrates, the key habitat factors were screened by canonical correspondence analysis (CCA) and Pearson correlation analysis. Suitability curves were determined by Generalized Additive Model (GAM). Ecosystem health comprehensive index method was used to evaluate the health status. The results show most suitable conditions for Corbicula fluminea containing chemical oxygen demand (CODMn) of 1.48 mg L−1, total nitrogen (TN) of 0.27 mg L−1, dissolved oxygen (DO) of 11.17 mg L−1, pH of 8.42, turbidity of 1.76 NTU, and water depth (Dep) of 0.35 m. The health status of QBR is spatially heterogeneous with the apparently better upstream than the downstream. In general, 25, 12.5, 12.5% of the samples were classified as nature, health and sub-health status, respectively and the rest 50% were lower than sub-health. The results are consistent with the environmental quality standards for surface water in China (GB3838-2002), suggesting the applicability of macroinvertebrates habitat suitability for evaluating river health. By minimizing the temporal and spatial limitations of comprehensive evaluation method and indicator species method, this study, for the first time, used macroinvertebrates habitat suitability curves to assess the health of medium and small rivers. The study will provide new insights for future river health assessments.

scholarly journals The inventory of vegetation cover of small river valleys in the north-east of the Samara Region

2021 ◽  
Vol 10 (1) ◽  
pp. 157-162
Author(s):  
Vera Valentinovna Solovieva
Keyword(s):  
Plant Species ◽  
Vegetation Cover ◽  
Higher Plants ◽  
Small River ◽  
Wild Plants ◽  
Small Rivers ◽  
North East ◽  
The North ◽  
The Right ◽  
River Valleys

The study covered 10 small rivers in the North-Eastern part of the Samara Volga region. The author studied the vegetation cover, which is understood as a set of phytocoenoses and their constituent plant species. On the territory of Pokhvistnevsky District, there are two groups of river valleys that are heterogeneous in geobotanical terms. The first group includes the rivers with forested valleys (Kutlugush, Murakla, Karmalka). Their slopes are more or less symmetrical and steep. The vegetation cover of an undeveloped floodplain is usually uniform, and there is usually no belt. The valleys of the second group are treeless; their slopes are sharply asymmetrical (Amanak, Tergala, Talkish). The right-bank tributary of the Maly Kinel River the Lozovka River with its length of 20 km and the left tributary Kuvayka River with its length of 16 km were studied on the territory of Kinel-Cherkassky District. The Padovka and Zaprudka rivers and the right tributaries of the Bolshoi Kinel River (Kinelsky District) were also studied. The most common associations are (Salix fragilis heteroherbosa, Scirpus sylvaticus purum, Agrostis stolonifera Amoria repens, Elytrigia repens + Poa angustifolia heteroherbosa). In total, 19 types of phytocoenoses were noted, 4 of them are found in half of the studied rivers. In the plant communities of small river valleys there are 232 species of higher wild plants, which belong to 139 genera from 48 families. This is 60% of the total number of higher plants registered in the flora of small river valleys of the Samara Region. Rare protected plant species are registered here: Adonis volgensis Steven ex DC., Cacalia hastata L., Delphinium cuneatum Stev. ex DC., Globularia punctata Lapeyr.

scholarly journals The Effect of Weathering on Salt Release from Coal Mine Spoils

Minerals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 760
Author(s):  
Melinda Hilton ◽  
Mandana Shaygan ◽  
Neil McIntyre ◽  
Thomas Baumgartl ◽  
Mansour Edraki
Keyword(s):  
Particle Size ◽  
Coal Mine ◽  
Chemical Weathering ◽  
Physical Weathering ◽  
Particle Size Fractions ◽  
Mine Spoils ◽  
Weathering Processes ◽  
Three Samples ◽  
Two Samples ◽  
Physical And Chemical

Coal mine spoils have the potential to create environmental impacts, such as salt load to surrounding environments, particularly when exposed to weathering processes. This study was conducted to understand the effect of physical and chemical weathering on the magnitude, rate, and dynamics of salt release from different coal mine spoils. Five spoil samples from three mines in Queensland were sieved to three different particle size fractions (<2 mm, 2–6 mm, and >6 mm). Two samples were dispersive spoils, and three samples were nondispersive spoils. The spoils were subjected to seven wet–dry cycles, where the samples were periodically leached with deionised water. The rate, magnitude, and dynamics of solutes released from spoils were spoil specific. One set of spoils did not show any evidence of weathering, but initially had higher accumulation of salts. In contrast, broad oxidative weathering occurred in another set of spoils; this led to acid generation and resulted in physical weathering, promoting adsorption–desorption and dissolution and, thus, a greater release of salts. This study indicated that the rate and magnitude of salt release decreased with increasing particle size. Nevertheless, when the spoil is dispersive, the degree of weathering manages salt release irrespective of initial particle size. This study revealed that the long-term salt release from spoils is not only governed by geochemistry, weathering degree, and particle size but also controlled by the water/rock ratio and hydrological conditions of spoils.

Evolution of the Martian Crust

2017 ◽  
Author(s):  
John C. Bridges
Keyword(s):  
Plate Tectonics ◽  
Chemical Weathering ◽  
Compositional Data ◽  
Crustal Contamination ◽  
Planetary Science ◽  
Mantle Metasomatism ◽  
Igneous Rocks ◽  
Forthcoming Article ◽  
Physical Weathering ◽  
Igneous Activity

This is an advance summary of a forthcoming article in the Oxford Encyclopedia of Planetary Science. Please check back later for the full article.Mars, which has a tenth of the mass of Earth, has cooled as a single lithospheric plate. Current topography gravity maps and magnetic maps do not show signs of the plate tectonics processes that have shaped the Earth’s surface. Instead, Mars has been shaped by the effects of meteorite bombardment, igneous activity, and sedimentary—including aqueous—processes. Mars also contains enormous igneous centers—Tharsis and Elysium, with other shield volcanoes in the ancient highlands. In fact, the planet has been volcanically active for nearly all of its 4.5 Gyr history, and crater counts in the Northern Lowlands suggest that may have extended to within the last tens of millions of years. Our knowledge of the composition of the igneous rocks on Mars is informed by over 100 Martian meteorites and the results from landers and orbiters. These show dominantly tholeiitic basaltic compositions derived by melting of a relatively K, Fe-rich mantle compared to that of the Earth. However, recent meteorite and lander results reveal considerable diversity, including more silica-rich and alkaline igneous activity. These show the importance of a range of processes including crystal fractionation, partial melting, and possibly mantle metasomatism and crustal contamination of magmas. The figures and plots of compositional data from meteorites and landers show the range of compositions with comparisons to other planetary basalts (Earth, Moon, Venus). A notable feature of Martian igneous rocks is the apparent absence of amphibole. This is one of the clues that the Martian mantle had a very low water content when compared to that of Earth.The Martian crust, however, has undergone hydrothermal alteration, with impact as an important heat source. This is shown by SNC analyses of secondary minerals and Near Infra-Red analyses from orbit. The associated water may be endogenous.Our view of the Martian crust has changed since Viking landers touched down on the planet in 1976: from one almost entirely dominated by basaltic flows to one where much of the ancient highlands, particularly in ancient craters, is covered by km deep sedimentary deposits that record changing environmental conditions from ancient to recent Mars. The composition of these sediments—including, notably, the MSL Curiosity Rover results—reveal an ancient Mars where physical weathering of basaltic and fractionated igneous source material has dominated over extensive chemical weathering.

An unusual weathered profile from Orange, N.S.W., Australia

Clay Minerals ◽  
1976 ◽  
Vol 11 (1) ◽  
pp. 65-71
Author(s):  
Peter Bayliss
Keyword(s):  
Mixed Layer ◽  
Chemical Weathering ◽  
Metamorphic Rock ◽  
Chemical Analyses ◽  
Thermogravimetric Analyses

AbstractSamples were collected from a 11·4 m deep weathered profile of a metamorphic rock. The mineralogy was determined from XRD powder patterns, differential thermal and thermogravimetric analyses with CEC determinations and chemical analyses.Four stages in a weathering sequence from the profile base towards the surface are as follows : (i) a partially regular trioctahedral chlorite-chlorite mixed layer ; (ii) a random chlorite-vermiculite mixed layer; (iii) a random chlorite-smectite mixed layer, and finally (iv) a smectite. Some chloritic layers are therefore more resistant to chemical weathering than other chloritic layers. This profile indicates that the order of decreasing resistance to chemical weathering is talc > smectite > tremolite.

scholarly journals Arctic–alpine blockfields in the northern Swedish Scandes: late Quaternary – not Neogene

2014 ◽  
Vol 2 (2) ◽  
pp. 383-401 ◽  
Author(s):  
B. W. Goodfellow ◽  
A. P. Stroeven ◽  
D. Fabel ◽  
O. Fredin ◽  
M.-H. Derron ◽  
...  
Keyword(s):  
Chemical Weathering ◽  
Late Quaternary ◽  
Time Frame ◽  
Temporal Variations ◽  
Early Pleistocene ◽  
Slope Position ◽  
Physical Weathering ◽  
Weathering Processes ◽  
Erosion Rates ◽  
Surrounding Landscape

Abstract. Autochthonous blockfield mantles may indicate alpine surfaces that have not been glacially eroded. These surfaces may therefore serve as markers against which to determine Quaternary erosion volumes in adjacent glacially eroded sectors. To explore these potential utilities, chemical weathering features, erosion rates, and regolith residence durations of mountain blockfields are investigated in the northern Swedish Scandes. This is done, firstly, by assessing the intensity of regolith chemical weathering along altitudinal transects descending from three blockfield-mantled summits. Clay / silt ratios, secondary mineral assemblages, and imaging of chemical etching of primary mineral grains in fine matrix are each used for this purpose. Secondly, erosion rates and regolith residence durations of two of the summits are inferred from concentrations of in situ-produced cosmogenic 10Be and 26Al in quartz at the blockfield surfaces. An interpretative model is adopted that includes temporal variations in nuclide production rates through surface burial by glacial ice and glacial isostasy-induced elevation changes of the blockfield surfaces. Together, our data indicate that these blockfields are not derived from remnants of intensely weathered Neogene weathering profiles, as is commonly considered. Evidence for this interpretation includes minor chemical weathering in each of the three examined blockfields, despite consistent variability according to slope position. In addition, average erosion rates of ~16.2 and ~6.7 mm ka−1, calculated for the two blockfield-mantled summits, are low but of sufficient magnitude to remove present blockfield mantles, of up to a few metres in thickness, within a late Quaternary time frame. Hence, blockfield mantles appear to be replenished by regolith formation through, primarily physical, weathering processes that have operated during the Quaternary. The persistence of autochthonous blockfields over multiple glacial–interglacial cycles confirms their importance as key markers of surfaces that were not glacially eroded through, at least, the late Quaternary. However, presently blockfield-mantled surfaces may potentially be subjected to large spatial variations in erosion rates, and their Neogene regolith mantles may have been comprehensively eroded during the late Pliocene and early Pleistocene. Their role as markers by which to estimate glacial erosion volumes in surrounding landscape elements therefore remains uncertain.

scholarly journals The geological setting of arsenic enrichment in groundwater of the shallow aquifers of the Tista Floodplain, Rangpur, Bangladesh

2020 ◽  
Vol 8 (2) ◽  
pp. 231
Author(s):  
Sudip Saha ◽  
A. H.M. Selim ◽  
Mrinal Kanti Roy
Keyword(s):  
Heavy Metals ◽  
Water Samples ◽  
Chemical Weathering ◽  
Anthropogenic Activities ◽  
Arsenic Concentration ◽  
Permissible Limit ◽  
Arsenic Content ◽  
Coating Materials ◽  
Silicate Minerals ◽  
Physical Weathering

Arsenic is present in water samples within the studied active floodplain areas of the Tista river, Rangpur Division, Bangladesh. All the water samples contain less arsenic than the WHO prescribed limit of 10 μg/L. 93.33% groundwater samples have higher Mn content than the permissible limit of 0.01 mg/L of WHO. The heavy metal concentrations of water can be expressed as Fe>Mn>Zn>As on the basis of their mean content. The heavy metals are negatively correlated with the well depth which is indicative of the influence of the anthropogenic activities on the concentrations of heavy metals. The arsenic concentration in water samples is higher in the central part of the study area. The coarser grain size, dominance of physical weathering, elevated topography and the effective flushing of groundwater resulted low concentration of arsenic in the groundwater. The EDS study reveals that arsenic occurs as coating materials of the silicate minerals. The river waters also have arsenic content lower than WHOs permissible limit. The factor analysis reveals that the iron and arsenic is released by the chemical weathering of arsenic bearing minerals like pyrite and arsenopyrite. The Fe and Mn derived in the groundwater by the chemical weathering of iron and manganese bearing minerals such as iron rich clay, silicate minerals and iron sulfides.  

scholarly journals Localization and Surface Characterization by Zhurong Mars Rover at Utopia Planitia

2021 ◽  
Author(s):  
Liang Ding ◽  
Ruyi Zhou ◽  
Tianyi Yu ◽  
Haibo Gao ◽  
Huaiguang Yang ◽  
...  
Keyword(s):  
Surface Characterization ◽  
Chemical Weathering ◽  
Friction Angle ◽  
Parameter Analysis ◽  
Mars Rover ◽  
Slip Ratio ◽  
Physical Weathering ◽  
Weathering Processes ◽  
Primary Localization

Abstract China’s first Mars rover, Zhurong, has successfully touched down on the southern Utopia Planitia of Mars at 109.925° E, 25.066° N, and since performed cooperative multiscale investigations with the Tianwen-1 orbiter. Here we present primary localization and surface characterization results based on complementary data of the first 60 sols. The Zhurong rover has traversed 450.9 m southwards over a flat surface with mild wheel slippage (less than 0.2 in slip ratio). The encountered crescent-shaped sand dune indicates a NE-SW local wind direction, consistent with larger-range remote-sensing observations. Soil parameter analysis based on terramechanics indicates that the topsoil has high bearing strength and cohesion, and its equivalent stiffness and internal friction angle are ~1390-5872 kPa∙m-n and ~21°-34° respectively. Rocks observed strewn with dense pits, or showing layered and flaky structures, are presumed to be involved in physical weathering like severe wind erosion and potential chemical weathering processes. These preliminary observations suggest great potential of in-situ investigations by the scientific payload suite of the Zhurong rover in obtaining new clues of the region’s aeolian and aqueous history. Cooperative investigations using the related payloads on both the rover and the obiter could peek into the habitability evolution of the northern lowlands on Mars.

scholarly journals Basin-centric approach to the sustainable development of agriculture in the context of climate change

2021 ◽  
pp. 5-13
Author(s):  
S.E. Dehodiuk ◽  
Е.G. Degodiyk ◽  
Yu.P. Borko
Keyword(s):  
Climate Change ◽  
Sustainable Development ◽  
Terrestrial Ecosystems ◽  
River Basins ◽  
Ecological Condition ◽  
Scientific Data ◽  
Small River ◽  
Nature Management ◽  
Small Rivers ◽  
Nature Restoration

The aim is to develop conceptual principles of sustainable development of the agrosphere and reproduction of degraded riverbeds of small rivers under climate change. Methods. Methodology and methods of system approach, monitoring, statistical analysis, and synthesis of scientific data. Results. It has been determined the ecological condition in Ukraine and the world has been by the manifestations of degradation processes in terrestrial ecosystems and small river basins on the principle of causation. It has been suggested the conceptual bases of restoration of channels of small rivers and their basins by carrying out engineering, culture-technical works in channels and floodplains of small rivers, the organization of adaptive landscaping of the territory, and also carrying out agro-, chemo-, bio- and phyto-meliorations in their basins without disturbance the basis of erosion and giving impetus to self-renewal of natural fauna and flora. In the processes of nature restoration, the leading role of domestic science in the methodological and methodological support of projects has been identified, and importance is attached to the restoration of natural biodiversity and biologization in agricultural systems. We proposed to create a state mortgage land bank with a concentration in it of land fees of ecological funds with the involvement of domestic and foreign investment. It is recommended to test the idea in several model pools of soil-climatic zones with further replication in Ukraine and the spread of technology beyond its borders. Conclusions. А systematic approach is needed to carry out reclamation works in the basins of small rivers is to implement the basin approach. To implement the program, the Verkhovna Rada of Ukraine must adopt the Law of Ukraine “On Agriculture, Sustainable Development of the Biosphere and Ecological Nature Management”, the project of which was developed at the NSC “Institute of Agriculture of NAAS”. The NSC “Institute of Agriculture of NAAS” with appropriate financial and personnel support on a multifunctional basis can perform the functions of a methodological center for the development of methodology and techniques of land management and reclamation in the process of restoring small river basins.

scholarly journals Effective Monitoring of Small River Basins

2002 ◽  
Vol 2 ◽  
pp. 1017-1021
Author(s):  
W. Symader ◽  
R. Bierl ◽  
A. Krein
Keyword(s):  
Water Quality ◽  
Fine Particles ◽  
River Basins ◽  
Small River ◽  
Chemical Data ◽  
Quality Data ◽  
Monitoring Station ◽  
Small Rivers ◽  
Water Quality Data ◽  
Short Pulses

As the transport of many pollutants occurs during high floods monitoring programs must focus on these intermittent events. In small rivers the pollutants start their travel as short pulses often associated with fine particles, but disperse on their way downstreams. Therefore the chemical data of a flood event are only representative of a small part of the basin adjacent to the monitoring station. This is usually not taken into account by evaluating water quality data.

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