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1
Bormans, Myriam, Phillip W. Ford, Larelle Fabbro, and Gary Hancock. "Onset and persistence of cyanobacterial blooms in a large impounded tropical river, Australia." Marine and Freshwater Research 55, no. 1 (2004): 1. http://dx.doi.org/10.1071/mf03045.
Анотація:
The dynamic interplay between physical, chemical and biological factors in the development and persistence of cyanobacterial blooms in impounded rivers is an important topic. Over a 3-year study period, variable climatic conditions were recorded in the Fitzroy River, Queensland, Australia, which is a typical, impounded lowland tropical river. Post-flood turbidity reduced the available light in the well-mixed water column to levels insufficient for cyanobacterial growth. Only when the water column stratified and the slowly sinking particles dropped from the surface layer did the ratio of surface mixed layer depth to euphotic depth approach 1, allowing cyanobacterial growth. By the time the light climate became favorable, most of the dissolved nutrients had been scavenged from the water column by settling particles or sequestered by fringing macrophytes and other biogeochemical processes. Cyanobacterial blooms dominated by Cylindrospermopsis raciborskii persisted for several months until the next flood flushed the system. The cyanobacterial species dominating that environment were very small and had high specific phosphorus uptake rates. Their nutrient requirement was met by transfer across the oxycline driven by regular high wind mixing events, entraining nutrient-rich bottom waters. Nutrient fluxes from the sediments into the anoxic bottom layer were sufficient to replace the bottom nutrients lost to the surface layer.
2
Lee, Cindy. "Passing the Baton to the Next Generation: A Few Problems That Need Solving." Annual Review of Marine Science 11, no. 1 (January 3, 2019): 1–13. http://dx.doi.org/10.1146/annurev-marine-010318-095342.
Анотація:
This is a personal account of some of the people and factors that were important in my career in chemical oceanography. I also discuss two areas of oceanographic research and training that I think need more attention. The first is how the difficulty in getting appropriate samples hampers our ability to fully understand biogeochemical processes in the sea. I have worked on dissolved materials, suspended and sinking particles, and sediments in lakes, oceans, rivers, and aerosols. Sample collection problems affect all those areas, although to different degrees. Second, I discuss a few of the issues that I most worry about with regard to graduate education in oceanography, among them an apparent decrease over the past several decades in the ability of many beginning students to write clearly and think logically.
3
Toro-Escobar, Carlos, Richard Voigt, Bruce Melville, Meng Chiew, and Gary Parker. "Riprap Performance at Bridge Piers Under Mobile-Bed Conditions." Transportation Research Record: Journal of the Transportation Research Board 1647, no. 1 (January 1998): 27–33. http://dx.doi.org/10.3141/1647-04.
Анотація:
Design criteria for riprap at bridge piers in rivers is based on the specification of a size, gradation, and cover that does not fail under an appropriately chosen flood flow. Experimental tests of riprap performance at bridge piers to date have relied on a configuration for which the ambient bed is not mobilized, that is, clear-water conditions. In the field, however, riprap is, as a rule, subjected to mobile-bed conditions during floods. Recent experiments by three cooperating research groups (University of Auckland, Nanyang University, and St. Anthony Falls Laboratory) indicate a heretofore unrecognized mechanism for riprap failure under mobile-bed conditions. When the flow is in the dune regime, the passage of successive dunes causes riprap that is never directly entrained by the flow to sink and disperse. Pier scour is realized as a consequence of these processes. In some cases, the depth of scour realized is not significantly less than that which would occur without riprap. When the riprap is fully underlain by a geotextile, edge effects can cause local removal of riprap, upturning of the geotextile, and general failure. When the riprap is underlain by a partial geotextile (i.e., one that covers an area less than the riprap), edge scour causes local sinking that anchors the geotextile. The sinking and dispersion of the rest of the riprap are greatly limited, and the riprap fails only when flow velocities are sufficient for direct entrainment. The experiments suggest improved design criteria for the installation of riprap in the field.
4
Gaye, B., M. G. Wiesner, and N. Lahajnar. "Nitrogen sources in the South China Sea, as discerned from stable nitrogen isotopic ratios in rivers, sinking particles, and sediments." Marine Chemistry 114, no. 3-4 (May 2009): 72–85. http://dx.doi.org/10.1016/j.marchem.2009.04.003.
5
Adel, Miah M. "The background state leading to arsenic contamination of Bengal Basin groundwater." Journal of Water and Health 3, no. 4 (December 1, 2005): 435–52. http://dx.doi.org/10.2166/wh.2005.053.
Анотація:
The Bengal basin has the world's densest water diversion constructions on the natural courses of rivers. The most damaging water diversion construction is the Farakka Barrage upon the international River Ganges. The diversion of water through this barrage and other constructions upstream of it has reduced the Ganges flow rate by 2.5 times. The resulting downstream effects are the depletion of surface water resources, more withdrawal than recharge of groundwater, sinking groundwater table, spread in depth and extension of the vadose zone, changes in surface features, climatic changes, etc. An investigation was carried out to find the contributions of water diversion to the arsenic contamination of groundwater in the Bengal basin. The reasonable scenario for arsenic contamination is the oxygen deficiency in groundwater and aeration of arsenopyrites buried in the sediment that would remain under water prior to 1975. The mineral forms water-soluble compounds of arsenic when react with atmospheric oxygen. These soluble arsenic compounds infiltrates to the groundwater. This article summarizes the short-time and incomplete study-based quick conclusions reached by investigators that have totally avoided the vital issue of water diversion. It then shows the depleting condition of the water resources under continuing diversions, the generation of favorable condition for arsenic release, the reasons for low sulfur concentration, the reason for first contamination in the Hugly basin, and the hindrance to water's self-purification. The articles advocates that the restoration of the virgin wetland ecosystems in the Bengal basin following the stoppage of the inordinate amount of unilateral upstream water withdrawals can remove the catastrophe.
6
Kumar, S., R. Ramesh, N. B. Bhosle, S. Sardesai, and M. S. Sheshshayee. "Natural isotopic composition of nitrogen in suspended particulate matter in the Bay of Bengal." Biogeosciences 1, no. 1 (October 14, 2004): 63–70. http://dx.doi.org/10.5194/bg-1-63-2004.
Анотація:
Abstract. We present the first measurement of nitrogen isotopic composition (δ15N) in suspended particulate matter (SPM) of the surface Bay of Bengal (BOB) at 24 different locations during pre- (April–May 2003) and post- (September–October 2002) monsoon seasons. The δ15N of particulate organic nitrogen (PON) in surface suspended matter of coastal as well as northern open BOB shows signatures of a two end-member mixing between continental inputs and marine sources. Dilution by the organic and detrital continental material brought in by rivers leads to consistently lower δ15N, evident from the relationship between surface salinity and δ15N. δ15N of surface PON of open ocean locations during both seasons, and also at coastal locations during pre-monsoon suggest the nitrate from deeper waters as a predominant source of nutrient for planktons. The depth profiles of δ15N of SPM during pre-monsoon season at nine different locations are also presented. These indicate an increase in δ15N by a maximum of 2.8‰ between euphotic depth and 300 m, which is lower than that observed in the eastern Indian Ocean, indicating the role of higher sinking rates of particles ballasted by aggregates of organic and mineral matter in BOB.
7
Kumar, S., R. Ramesh, N. B. Bhosle, S. Sardesai, and M. S. Sheshshayee. "Natural isotopic composition of nitrogen in suspended particulate matter in the Bay of Bengal." Biogeosciences Discussions 1, no. 1 (June 4, 2004): 87–105. http://dx.doi.org/10.5194/bgd-1-87-2004.
Анотація:
Abstract. We present the first measurement of nitrogen isotopic composition (δ15N) in suspended particulate matter (SPM) of the surface Bay of Bengal (BOB) at 24 different locations during pre- (April–May 2003) and post- (September–October 2002) monsoon seasons. The δ15N of particulate organic nitrogen (PON) in surface suspended matter of coastal as well as northern open BOB shows signatures of a two end-member mixing between continental inputs and marine sources. Dilution by the organic and detrital continental material brought in by rivers leads to consistently lower δ15N, evident from the relationship between surface salinity and δ15N. δ15N of surface PON of open ocean locations during both seasons, and also at coastal locations during pre-monsoon suggest the nitrate from deeper waters as a predominant source of nutrient for planktons. The depth profiles of δ15N of SPM during pre-monsoon season at nine different locations are also presented. These indicate an increase in δ15N by a maximum of 2.8‰ between euphotic depth and 300 m, which is lower than that observed in the eastern Indian Ocean, indicating the role of higher sinking rates of particles ballasted by aggregates of organic and mineral matter in BOB.
8
Hubbitdinova, Nerkes. "Artistic and Aesthetic Representation of the Mythological Image of the Water Damosel in the Bashkir Folk Epic (on the Material of the Epics “Akbuzatˮ and “Zayatulyak and Khyuhyluˮ)". Philology & Human, № 2 (21 липня 2021): 134–42. http://dx.doi.org/10.14258/filichel(2021)2-12.
Анотація:
Using the Bashkir epics “Akbuzatˮ and “Zayatulyk and Khyukhyluˮ, the article examines the mythical image of the water damosel – khaukhylu, which has significant artistic and aesthetic functions. This image takes a special place in the mythology of all peoples and in ancient sacred beliefs. Due to the fact that after the adoption of Christianity / Islam among the peoples, all the once sacred, pagan deities – the keepers of rivers and lakes, mountains and natural boundaries, forests and fields, as well as the ones connected with home, were endowed with a negative characteristic and began to be represented as an evil spirit. Such a fate was waiting for, for example, the traditional hero Baba Yaga – Yashchura, raised to the rank of a positive character, deified by the canon of the ancient Slavs, she was the keeper of the clan, its traditions and customs. Accordingly, after the adoption of Christianity, Yashchura took on that negative, pernicious character known to us from Slavic folk tales and folkloric accounts. As E.V. Pomerantsev correctly states, in the artistic and aesthetic sense in mythological legends and folkloric accounts there are always similar motives of “sudden meetingˮ, “sinking into the underwater kingdomˮ, “awards of the water kingˮ, “... the marriage of a hero in the underwater kingdomˮ, etc. In the Bashkir epic monuments observed in the article, these motives are strictly traced and successfully actualized.
9
Gilfillan, Dennis, Timothy A. Joyner, and Phillip Scheuerman. "Maxent estimation of aquaticEscherichia colistream impairment." PeerJ 6 (September 13, 2018): e5610. http://dx.doi.org/10.7717/peerj.5610.
Анотація:
BackgroundThe leading cause of surface water impairment in United States’ rivers and streams is pathogen contamination. Although use of fecal indicators has reduced human health risk, current approaches to identify and reduce exposure can be improved. One important knowledge gap within exposure assessment is characterization of complex fate and transport processes of fecal pollution. Novel modeling processes can inform watershed decision-making to improve exposure assessment.MethodsWe used the ecological model, Maxent, and the fecal indicator bacteriumEscherichia colito identify environmental factors associated with surface water impairment.Samples were collected August, November, February, and May for 8 years on Sinking Creek in Northeast Tennessee and analyzed for 10 water quality parameters andE. coliconcentrations. Univariate and multivariate models estimated probability of impairment given the water quality parameters. Model performance was assessed using area under the receiving operating characteristic (AUC) and prediction accuracy, defined as the model’s ability to predict both true positives (impairment) and true negatives (compliance). Univariate models generated action values, or environmental thresholds, to indicate potentialE. coliimpairment based on a single parameter. Multivariate models predicted probability of impairment given a suite of environmental variables, and jack-knife sensitivity analysis removed unresponsive variables to elicit a set of the most responsive parameters.ResultsWater temperature univariate models performed best as indicated by AUC, but alkalinity models were the most accurate at correctly classifying impairment. Sensitivity analysis revealed that models were most sensitive to removal of specific conductance. Other sensitive variables included water temperature, dissolved oxygen, discharge, and NO3. The removal of dissolved oxygen improved model performance based on testing AUC, justifying development of two optimized multivariate models; a 5-variable model including all sensitive parameters, and a 4-variable model that excluded dissolved oxygen.DiscussionResults suggest thatE. coliimpairment in Sinking Creek is influenced by seasonality and agricultural run-off, stressing the need for multi-month sampling along a stream continuum. Although discharge was not predictive ofE. coliimpairment alone, its interactive effect stresses the importance of both flow dependent and independent processes associated withE. coliimpairment.This research also highlights the interactions between nutrient and fecal pollution, a key consideration for watersheds with multiple synergistic impairments. Although one indicator cannot mimic theplethora of existing pathogens in water, incorporating modeling can fine tune an indicator’s utility, providing information concerning fate, transport, and source of fecal pollution while prioritizing resources and increasing confidence in decision making.
10
Kausarian, Husnul, Batara Batara, and Dewandra Bagus Eka Putra. "The Phenomena of Flood Caused by the Seawater Tidal and its Solution for the Rapid-growth City: A case study in Dumai City, Riau Province, Indonesia." Journal of Geoscience, Engineering, Environment, and Technology 3, no. 1 (March 1, 2018): 39. http://dx.doi.org/10.24273/jgeet.2018.3.01.1221.
Анотація:
A strategic city located on the northern coast of Sumatera Island known as Dumai City. This city is a growth and industrial city that always increase everyday economically. This city faces the flood problem that not only from the excess water from the rain, but also from the phenomena of seawater tidal. The tidal should not reach the mainland for the ideal situation, but the urbanization and development problem made it happen. Field observation and satellite data analysis shows the problem that happened in this city, also find out the solution how to make the seawater tidal will not being the flood when it occurs. The flood caused by the inadequate drainage condition is exacerbated by the low awareness of people who still do not maintain cleanliness, a lot of garbage that accumulates in the drainage causing the process of water flow to be inhibited. Geologically, the base rock of Dumai City consists of sand and peat which logically is a good system to absorb water because sand and peat are materials that have high porosity. Topographically, the city of Dumai is at an average height of three meters above sea level, so in fact, this city could be spared from the flood caused by the tide when it occurs. The solutions that can be proposed for this city are making the rivers being clean with normalization, well-designed drainage, Watergate and making an artificial lake for sinking the tidal seawater.
11
Baković, Najla, Ferry J. Siemensma, Robert Baković, and Josip Rubinić. "Testate Amoebae in Karst Caves of the Dinaric Arc (South-Eastern Europe) with a Description of Centropyxis bipilata sp. nov." Acta Protozoologica 58, no. 4 (2019): 201–15. http://dx.doi.org/10.4467/16890027ap.19.018.12020.
Анотація:
Karst freshwater caves are subterranean habitats characterized by the constant absence of light and relatively small variations of temperature and air humidity. They are mostly food deprived environments, with the exception if large bat colonies are present or if they are intensively supplied with organic matter by sinking rivers. Even though these habitats are often described as harsh, they have enabled the evolution of highly specialized and often endemic animals. The cave eukaryotic micro-organisms, on the other hand, are scarcely researched. The results of research of testate amoebae in the caves of the Dinaric arc detected 23 species, 12 of which were first found in caves. Also, a description of Centropyxis bipilata sp. nov. is presented. This species is clearly distinguished from other described species based on shell size, the presence of two struts and the usually dark ring around the aperture. Testate amoebae were registered on aquatic and terrestrial cave sediments and transitional habitats (like hygropetric and wet walls). The most frequent species within the samples were: Trinema lineare, Cryptodifflugia oviformis and Centropyxis bipilata sp. nov. Maximum diversity of testate amoebae was registered in Ponor Kovači with twenty species. In 24.4 % of the investigated samples microphototrophs were found, implying good surface-subsurface connectivity that could also affect testate amoebae diversity. This research showed that caves are underestimated habitats that can provide us with new data about the testate amoebae biogeography and diversity.
12
Benischke, Ralf. "Review: Advances in the methodology and application of tracing in karst aquifers." Hydrogeology Journal 29, no. 1 (January 20, 2021): 67–88. http://dx.doi.org/10.1007/s10040-020-02278-9.
Анотація:
AbstractTracer methods have been widely used in many fields of environmental and natural sciences, and also in human health sciences. In particular, tracers are used in the study of karst hydrogeology, typically focusing on phenomena such as sinkholes, sinking rivers and large karst springs. It is known that tracers have been used since antiquity. The aim of tracer tests has been to investigate underground flow paths, transport processes and water–rock interactions, and to get an insight into the functioning of a karst aquifer. In karst hydrogeology, tracer methods are the most important investigation tools beside conventional hydrological methods. In early times, tracer methods were applied only to investigate underground flow-paths. Later they were also used to elucidate transport processes associated with water flow, and today they are often the basis, together with detailed hydrological information, of groundwater protection investigations and aquifer modelling. Many substances (spores, microspheres, bacteriophages, salt tracers, fluorescent dyes, radioactive substances) have been investigated for their properties and potential usage in environmental investigations, in particular the often unknown and inaccessible underground systems of karst areas. A great number of analytical techniques is available. This includes instrumentation for laboratory applications and direct online, on-site or in-situ field measurements. Modern instruments have a high capability for data acquisition, storage and transmission in short intervals, as a basis for quantitative evaluation and modelling. This enables research on the hydrological and hydrochemical dynamics of aquifers and their response to different natural or anthropogenic impacts.
13
Triwurjani, Rr, and Shinatria Adhityatama. "ARKEOLOGI BAWAH AIR: TEMUAN TEMBIKAR SITUS TERENDAM DI DANAU MATANO, SULAWESI SELATAN." KALPATARU 28, no. 1 (November 19, 2019): 13. http://dx.doi.org/10.24832/kpt.v28i1.533.
Анотація:
Abstract. Underwater archaeological research usually talks about archaeological remains under the sea like a sinking ship. The issue of sinking ships concerns the cargo, the type of ship, shipping lines, trade routes, and the origin and technology of shipbuilding. The problem is that archeological findings are not only in the sea, but also in lakes, swamps, or rivers. Therefore underwater archeology not only studies archeological findings in the sea but also on the lake. Archaeological findings originating from within the Matano lake include in the form of pottery both intact and fractions mixed with metal objects. Lake Matano located in Luwu Regency in South Sulawesi is an ancient lake and is the deepest lake in Southeast Asia. How and why these pottery findings arrived inside the lake, are the problems that will be answered in this study. The aim is to find out the function and role of pottery in the sites of Lake Matano and what factors influence it. With the method of inductive reasoning and underwater exploration and land and an analogy with the findings of similar pottery in the terrestrial area of the lake, we can find a connection between the findings of pottery and the same activities related to the manufacture of metal objects, and strong suspicion of tectonic activity that affects the site's existence.Keywords: Pottery, Underwater, Terrestrial, Metal, Lake MatanoAbstrak. Penelitian arkeologi bawah air biasanya berbicara tentang tinggalan arkeologi di bawah laut seperti kapal tenggelam. Isu kapal tenggelam ini menyangkut tentang muatan, jenis kapal, jalur pelayaran, jalur perdagangan, dan asal muasal dan teknologi pembuatan kapal. Permasalahannya, temuan arkeologi tidak saja berada di dalam laut, tetapi juga terdapat di perairan danau, rawa, ataupun sungai. Oleh karena itu, arkeologi bawah air tidak saja mempelajari temuan arkeologi di dalam laut, tetapi juga di danau. Temuan arkeologi yang berasal dari dalam Danau Matano antara lain berupa tembikar, baik utuh maupun pecahan yang bercampur dengan benda logam. Danau Matano yang terletak di Kabupaten Luwu di Sulawesi Selatan adalah danau purba dan merupakan danau terdalam di Asia Tenggara. Bagaimana dan mengapa temuan tembikar ini sampai berada di dalam danau adalah permasalahan yang hendak dijawab dalam penelitian ini. Tujuannya adalah untuk mengetahui fungsi dan peran keberadaan tembikar di situs-situs Danau Matano dan faktor-faktor apa yang mempengaruhinya. Dengan metode penalaran induktif dan ekplorasi bawah air dan daratan serta analogi dengan temuan tembikar serupa di area terrestrial danau dapat diketahui adanya hubungan antara temuan tembikar dengan aktivitas yang sama berkaitan dengan pembuatan benda logam, dan dugaan kuat adanya aktivitas tektonik yang mempengaruhi keberadaan situs.Kata kunci: Tembikar, Bawah air, Terrestrial, logam, Danau Matano
14
Triwurjani, Rr, and Shinatria Adhityatama. "ARKEOLOGI BAWAH AIR: TEMUAN TEMBIKAR SITUS TERENDAM DI DANAU MATANO, SULAWESI SELATAN." KALPATARU 28, no. 1 (July 22, 2019): 13. http://dx.doi.org/10.24832/kpt.v28i1.572.
Анотація:
Underwater archaeological research usually talks about archaeological remains under the sea like a sinking ship. The issue of sinking ships concerns the cargo, the type of ship, shipping lines, trade routes, and the origin and technology of shipbuilding. The problem is that archeological findings are not only in the sea, but also in lakes, swamps, or rivers. Therefore underwater archeology not only studies archeological findings in the sea but also on the lake. Archaeological findings originating from within the Matano lake include in the form of pottery both intact and fractions mixed with metal objects. Lake Matano located in Luwu Regency in South Sulawesi is an ancient lake and is the deepest lake in Southeast Asia. How and why these pottery findings arrived inside the lake, are the problems that will be answered in this study. The aim is to find out the function and role of pottery in the sites of Lake Matano and what factors influence it. With the method of inductive reasoning and underwater exploration and land and an analogy with the findings of similar pottery in the terrestrial area of the lake, we can find a connection between the findings of pottery and the same activities related to the manufacture of metal objects, and strong suspicion of tectonic activity that affects the site's existence. Keywords: Pottery, Underwater, Terrestrial, Metal, Lake MatanoPenelitian arkeologi bawah air biasanya berbicara tentang tinggalan arkeologi di bawah laut seperti kapal tenggelam. Isu kapal tenggelam ini menyangkut tentang muatan, jenis kapal, jalur pelayaran, jalur perdagangan, dan asal muasal dan teknologi pembuatan kapal. Permasalahannya, temuan arkeologi tidak saja berada di dalam laut, tetapi juga terdapat di perairan danau, rawa, ataupun sungai. Oleh karena itu, arkeologi bawah air tidak saja mempelajari temuan arkeologi di dalam laut, tetapi juga di danau. Temuan arkeologi yang berasal dari dalam Danau Matano antara lain berupa tembikar, baik utuh maupun pecahan yang bercampur dengan benda logam. Danau Matano yang terletak di Kabupaten Luwu di Sulawesi Selatan adalah danau purba dan merupakan danau terdalam di Asia Tenggara. Bagaimana dan mengapa temuan tembikar ini sampai berada di dalam danau adalah permasalahan yang hendak dijawab dalam penelitian ini. Tujuannya adalah untuk mengetahui fungsi dan peran keberadaan tembikar di situs-situs Danau Matano dan faktor-faktor apa yang mempengaruhinya. Dengan metode penalaran induktif dan ekplorasi bawah air dan daratan serta analogi dengan temuan tembikar serupa di area terrestrial danau dapat diketahui adanya hubungan antara temuan tembikar dengan aktivitas yang sama berkaitan dengan pembuatan benda logam, dan dugaan kuat adanya aktivitas tektonik yang mempengaruhi keberadaan situs.Kata Kunci: Tembikar, Bawah air, Terrestrial, logam, Danau Matano
15
Menzel Barraqueta, Jan-Lukas, Christian Schlosser, Hélène Planquette, Arthur Gourain, Marie Cheize, Julia Boutorh, Rachel Shelley, et al. "Aluminium in the North Atlantic Ocean and the Labrador Sea (GEOTRACES GA01 section): roles of continental inputs and biogenic particle removal." Biogeosciences 15, no. 16 (August 30, 2018): 5271–86. http://dx.doi.org/10.5194/bg-15-5271-2018.
Анотація:
Abstract. The distribution of dissolved aluminium (dAl) in the water column of the North Atlantic and Labrador Sea was studied along GEOTRACES section GA01 to unravel the sources and sinks of this element. Surface water dAl concentrations were low (median of 2.5 nM) due to low aerosol deposition and removal by biogenic particles (i.e. phytoplankton cells). However, surface water dAl concentrations were enhanced on the Iberian and Greenland shelves (up to 30.9 nM) due to continental inputs (rivers, glacial flour, and ice melt). Dissolved Al in surface waters scaled negatively with chlorophyll a and biogenic silica (opal) concentrations. The abundance of diatoms exerted a significant (p<0.01) control on the surface particulate Al (pAl) to dAl ratios by decreasing dAl levels and increasing pAl levels. Dissolved Al concentrations generally increased with depth and correlated strongly with silicic acid (R2>0.76) west of the Iberian Basin, suggesting net release of dAl at depth during remineralization of sinking opal-containing particles. Enrichment of dAl at near-bottom depths was observed due to the resuspension of sediments. The highest dAl concentrations (up to 38.7 nM) were observed in Mediterranean Outflow Waters, which act as a major source of dAl to mid-depth waters of the eastern North Atlantic. This study clearly shows that the vertical and lateral distributions of dAl in the North Atlantic differ when compared to other regions of the Atlantic and global oceans. Responsible for these large inter- and intra-basin differences are the large spatial variabilities in the main Al source, atmospheric deposition, and the main Al sink, particle scavenging by biogenic particles.
16
D'Angelo, Alessandra, Federico Giglio, Stefano Miserocchi, Anna Sanchez-Vidal, Stefano Aliani, Tommaso Tesi, Angelo Viola, Mauro Mazzola, and Leonardo Langone. "Multi-year particle fluxes in Kongsfjorden, Svalbard." Biogeosciences 15, no. 17 (September 4, 2018): 5343–63. http://dx.doi.org/10.5194/bg-15-5343-2018.
Анотація:
Abstract. High-latitude regions are warming faster than other areas due to reduction of snow cover and sea ice loss and changes in atmospheric and ocean circulation. The combination of these processes, collectively known as polar amplification, provides an extraordinary opportunity to document the ongoing thermal destabilisation of the terrestrial cryosphere and the release of land-derived material into the aquatic environment. This study presents a 6-year time series (2010–2016) of physical parameters and particle fluxes collected by an oceanographic mooring in Kongsfjorden (Spitsbergen, Svalbard). In recent decades, Kongsfjorden has been experiencing rapid loss of sea ice coverage and retreat of local glaciers as a result of the progressive increase in ocean and air temperatures. The overarching goal of this study was to continuously monitor the inner fjord particle sinking and to understand to what extent the temporal evolution of particulate fluxes was linked to the progressive changes in both Atlantic and freshwater input. Our data show high peaks of settling particles during warm seasons, in terms of both organic and inorganic matter. The different sources of suspended particles were described as a mixing of glacier carbonate, glacier siliciclastic and autochthonous marine input. The glacier releasing sediments into the fjord was the predominant source, while the sediment input by rivers was reduced at the mooring site. Our time series showed that the seasonal sunlight exerted first-order control on the particulate fluxes in the inner fjord. The marine fraction peaked when the solar radiation was at a maximum in May–June while the land-derived fluxes exhibited a 1–2-month lag consistent with the maximum air temperature and glacier melting. The inter-annual time-weighted total mass fluxes varied by 2 orders of magnitude over time, with relatively higher values in 2011, 2013, and 2015. Our results suggest that the land-derived input will remarkably increase over time in a warming scenario. Further studies are therefore needed to understand the future response of the Kongsfjorden ecosystem alterations with respect to the enhanced release of glacier-derived material.
17
Ternon, E., C. Guieu, M. D. Loÿe-Pilot, N. Leblond, E. Bosc, B. Gasser, J. C. Miquel, and J. Martín. "The impact of Saharan dust on the particulate export in the water column of the North Western Mediterranean Sea." Biogeosciences 7, no. 3 (March 2, 2010): 809–26. http://dx.doi.org/10.5194/bg-7-809-2010.
Анотація:
Abstract. Simultaneous measurements of atmospheric deposition and of sinking particles at 200 and 1000 m depth, were performed in the Ligurian Sea (North-Western Mediterranean) between 2003 and 2007, along with phytoplanktonic activity derived from satellite images. Atmospheric deposition of Saharan dust particles was very irregular and confirmed the importance of sporadic high magnitude events over the annual average (11.4 g m−2 yr−1 for the 4 years). The average marine total mass flux was 31 g m−2 yr−1, the larger fraction being the lithogenic one (~37%). The marine total mass flux displayed a seasonal pattern with a maximum in winter, occurring before the onset of the spring bloom. The highest POC fluxes did not occur during the spring bloom nor could they be directly related to any noticeable increase in the surface phytoplanktonic biomass. Over the 4 years of the study, the strongest POC fluxes were concomitant with large increases of the lithogenic marine flux, which had originated from either recent Saharan fallout events (February 2004 and August 2005), from "old" Saharan dust "stored" in the upper water column layer (March 2003 and February 2005), or alternatively from lithogenic material originating from Ligurian riverine flooding (December 2003, Arno, Roya and Var rivers). Those associated export fluxes defined as "lithogenic events", are believed to result from a combination of forcing (winter mixing or Saharan events, in particular extreme ones), biological (zooplankton) activity, and also organic-mineral aggregation inducing a ballast effect. By fertilising the surface layer, mixed Saharan dust events were shown to be able to induce "lithogenic events" during the stratification period. These events would be more efficient in transferring POC to the deeper layers than the spring bloom itself. The extreme Saharan event of February 2004 exported ~45% of the total annual POC, compared to an average of ~25% for the bloom period. This emphasises the role played by these "lithogenic events", and in particular those that are induced by the more extreme Saharan events, in the carbon export efficiency in the North-western Mediterranean Sea.
18
Ternon, E., C. Guieu, M. D. Loÿe-Pilot, N. Leblond, E. Bosc, B. Gasser, and J. C. Miquel. "The impact of Saharan dust on the particulate export in the water column of the North Western Mediterranean Sea." Biogeosciences Discussions 6, no. 6 (November 17, 2009): 10737–73. http://dx.doi.org/10.5194/bgd-6-10737-2009.
Анотація:
Abstract. Simultaneous measurements of atmospheric deposition and of sinking particles at 200 m depth, were performed in the Ligurian Sea (North-Western Mediterranean) between 2003 and 2007 along with the historical time records of phytoplanktonic activity from satellite images. Atmospheric deposition of Saharan dust particles was very irregular and confirmed the importance of sporadic high magnitude events over the annual average (11.4 g m−2 yr−1 for the 4 yr). The average marine total mass flux was 31 g m−2 yr−1, the larger fraction being the lithogenic one (~37%). The marine total mass flux displayed a seasonal pattern with a maximum in winter occurring before the onset of the spring bloom. The highest POC fluxes did not occur during the spring bloom nor could they be related to any noticeable increase in the surface phytoplanktonic activity. Over the 4 yr of the study, the strongest POC fluxes were concomitant with large increases of the lithogenic marine flux, which had originated from either recent Saharan fallout events (February 2004, August 2005), or from ''old'' Saharan dust ''stored'' in the upper water column layer (March 2003, February 2005), or alternatively from lithogenic material originating from Ligurian riverine flooding (December 2003, Arno, Roya and Var rivers). These ''lithogenic events'' are believed to result from a combination of physical processes (winter mixing), the aggregation of faecal pellets resulting from zooplankton activity, and also organic-mineral aggregation inducing a ballast effect. However, such an event also occurred in August 2005 without any physical mixing, and was attributed to Saharan dust-induced biological enhancement. POC export provoked by the simultaneous occurrence of winter mixing and an extreme dust event (February 2004, 22 g m−2 deposition) was shown to represent 50% of the total annual POC export at 200 m in the water column that year, as compared to only ~25% for the bloom period. This indicates the importance of atmospheric deposition for POC fluxes in the Mediterranean Sea, which is an area strongly influenced by Saharan dust inputs.
19
Tosic, Radislav, and Cedomir Crnogorac. "The morphological and hydrological evolution of the sinking creek Puljica potok." Glasnik Srpskog geografskog drustva 85, no. 2 (2005): 17–22. http://dx.doi.org/10.2298/gsgd0502017t.
Анотація:
The karst morphology of the river basin of Mala Ukrina is characterized apart from superficial and ground karst forms, by karst hydrography, which gives to this area a specific hydrological mark. In this part of the basin as a hydrological peculiarity of limestone plain, we can single out the lost river Puljica potok, which is the water most lost river in the south rim of the Panonion basin of the Republic of Srpska that has been discovered so far.
20
Djeric, Gordana. "Sinking river: On inconstant status of mentality and mental mapping phenomena." Bulletin de l'Institut etnographique 63, no. 2 (2015): 369–82. http://dx.doi.org/10.2298/gei1502369d.
21
Perkins, Sid. "O river deltas, where art thou?: Coastal sinking stalls sediment accumulation." Science News 172, no. 8 (September 30, 2009): 118. http://dx.doi.org/10.1002/scin.2007.5591720808.
22
Hao, Yan Guang, Xiang Liang Liu, and Jian Bo Liu. "GPS RTK Techniques for Construction Monitoring of Super Deep-Water Open-Caisson." Applied Mechanics and Materials 580-583 (July 2014): 2865–71. http://dx.doi.org/10.4028/www.scientific.net/amm.580-583.2865.
Анотація:
The super open-caisson foundation of Taizhou Yangtze River Bridge was used by positioning system of anchor piers. GPS RTK Techniques was used to real-time monitor the open-caisson and by software compute current geometric posture of open-caisson timely. This could provide guarantee for sinking of caisson, and shorten construction period and save cost.
23
Yuan, Yu Qing, Wei Li, Tian Wen Yang, and Tao Guo. "Impact Compaction Technology of Filling Subgrade with Yellow River Sandy Soil." Applied Mechanics and Materials 193-194 (August 2012): 717–20. http://dx.doi.org/10.4028/www.scientific.net/amm.193-194.717.
Анотація:
In order to reduce sinking after subgrade construction, impact compaction technology was put forward. The engineering characteristics of Yellow River sandy soil located in Kaifeng, and impact compaction technologies were analyzed. The contrast tests were also carried through, including vibration compaction and impact one. The results show that the subgrade can obtain higher compaction degree with impact compaction technology than the other method, with 2%-5% increasing.
24
Hoson, T., S. Hayashi, and K. Hattori. "The contribution of sedimentation of algal cell to the downstream levels of musty odor." Water Science and Technology 31, no. 11 (June 1, 1995): 139–44. http://dx.doi.org/10.2166/wst.1995.0423.
Анотація:
In Lake Biwa, there are two peaks of 2-methylisoborneol (MIB) production, each of which is due to the different MIB producing algae, Phormidium and Oscillatoria. The former grows in early summer, whereas the latter grows in late summer. Levels of MIB were determined for water samples collected from Lake Biwa and the lower sampling site of Murano Water Treatment Plant's intake on Yodo River. MIB concentrations detected at the lower site differed between the two odor seasons. In the first episode due to growth of Phormidium, MIB level at the lower site was almost the same as that in the lake, whereas it was clearly lower than that of the lake in the second episode caused by Oscillatoria. No differences in flow ratio of the lake effluent to that of Yodo River were detected between the two odor seasons. Thus, the difference in MIB concentration between the lake and the lower site in the second episode may be caused by a decrease in cell-associated MIB due to the high sinking rate of Oscillatoria. The sinking rate ofOscillatoria trichome was twenty times higher than that of Phormidium.
25
Sousa, J. J., and L. Bastos. "Multi-temporal SAR interferometry reveals acceleration of bridge sinking before collapse." Natural Hazards and Earth System Sciences 13, no. 3 (March 18, 2013): 659–67. http://dx.doi.org/10.5194/nhess-13-659-2013.
Анотація:
Abstract. On the night of 4 March 2001, at Entre-os-Rios (Northern Portugal), the Hintze Ribeiro centennial bridge collapsed killing 59 people traveling in a bus and three cars that were crossing the Douro River. According to the national authorities, the collapse was due to two decades of uncontrolled sand extraction which compromised the stability of the bridge's pillars, together with underestimating the warnings from divers and technicians. In this work we do not intend to corroborate or contradict the official version of the accident's causes, but only demonstrate the potential of Multi-Temporal Interferometric techniques for detection and monitoring of deformations in structures such as bridges, and consequently the usefulness of the derived information in some type of early warning system to help prevent new catastrophic events. Based on the analysis of 52 ERS-1/2 covering the period from May 1995 to the fatal occurrence, we were able to detect significant movements, reaching rates of 20 mm yr−1, in the section of the bridge that fell into the Douro River, which are obvious signs of the bridge's instability. These promising results demonstrate that with the new high-resolution synthetic aperture radar satellite scenes it is possible to develop interferometric based methodologies for structural health monitoring.
26
Rixen, Tim, Birgit Gaye, Kay-Christian Emeis, and Venkitasubramani Ramaswamy. "The ballast effect of lithogenic matter and its influences on the carbon fluxes in the Indian Ocean." Biogeosciences 16, no. 2 (January 29, 2019): 485–503. http://dx.doi.org/10.5194/bg-16-485-2019.
Анотація:
Abstract. Data obtained from long-term sediment trap experiments in the Indian Ocean in conjunction with satellite observations illustrate the influence of primary production and the ballast effect on organic carbon flux into the deep sea. They suggest that primary production is the main control on the spatial variability of organic carbon fluxes at most of our study sites in the Indian Ocean, except at sites influenced by river discharges. At these sites the spatial variability of organic carbon flux is influenced by lithogenic matter content. To quantify the impact of lithogenic matter on the organic carbon flux, the densities of the main ballast minerals, their flux rates and seawater properties were used to calculate sinking speeds of material intercepted by sediment traps. Sinking speeds in combination with satellite-derived export production rates allowed us to compute organic carbon fluxes. Flux calculations imply that lithogenic matter ballast increases organic carbon fluxes at all sampling sites in the Indian Ocean by enhancing sinking speeds and reducing the time of organic matter respiration in the water column. We calculated that lithogenic matter content in aggregates and pellets enhances organic carbon flux rates on average by 45 % and by up to 62 % at trap locations in the river-influenced regions of the Indian Ocean. Such a strong lithogenic matter ballast effect explains the fact that organic carbon fluxes are higher in the low-productive southern Java Sea compared to the high-productive western Arabian Sea. It also implies that land use changes and the associated enhanced transport of lithogenic matter from land into the ocean may significantly affect the CO2 uptake of the organic carbon pump in the receiving ocean areas.
27
Hooper, Jennifer J., Tim Foecke, Lori Graham, and Timothy P. Weihs. "Metallurgical Analysis of Wrought Iron From the RMS Titanic." Marine Technology and SNAME News 40, no. 02 (April 1, 2003): 73–81. http://dx.doi.org/10.5957/mt1.2003.40.2.73.
Анотація:
The discovery of the RMS Titanic has led to a number of scientific studies, one of which addresses the role that structural materials played in the sinking of the ship. Early studies focused on the quality of the hull steel as a contributing factor in the ship's rapid sinking, but experimental results showed that the material was "state-of-the-art" for 1911. Instead, it was suggested that the quality of the wrought iron rivets may have been an important factor in the opening of the steel plates during flooding. Here the quality of RMS Titanic wrought iron is examined and compared with contemporary wrought iron obtained from additional late 19th-/early 20th-century buildings, bridges, and ships. Traditional metallurgical analysis as well as compositional analysis, mechanical testing, and computer modeling are used to understand the variation in the mechanical properties of wrought iron as a function of its microstructure.
28
Sket, Boris. "HIGH BIODIVERSITY IN HYPOGEAN WATERS AND ITS ENDANGERMENT – THE SITUATION IN SLOVENIA, THE DINARIC KARST, AND EUROPE." Crustaceana 72, no. 8 (1999): 767–79. http://dx.doi.org/10.1163/156854099503951.
Анотація:
AbstractOf approximately 12,600 aquatic animal species, registered in 1978 in Europe, more than 200 were facultative cave dwellers, approximately 1,000 species (in 1998 already 2,000 taxa) or 8%, were specialized stygobionts. More than half are Crustacea. The relatively high number of crustacean hypogean species is rendered possible mainly by (1) the absence of their insect competitors as well as (2) spatial partition due to the small distribution areas of most stygobionts. Slovenia, with approximately 200 taxa in its 20,000 km2, has the highest density, and the Dinaric area with nearly 400 taxa in its only 153,400 km2 has the highest absolute number of stygobiont taxa known in the world. The situation is similar for terrestrial cave faunas. The crustacean diversity is mostly a result of ecological and morphological diversification within a few genera (e.g., Niphargus, Proasellus, Monolistra). However, higher taxa (families, orders) are well represented. Besides some non-specialized newcomers to hypogean habitats, some ubiquitous species (e.g., Asellus aquaticus, Synurella ambulans) possess a number of isolated hypogean populations that are troglomorphic to varying degrees. Hypogean species are endangered by urbanization and other uses of the sensitive karst landscape. Although a slight organic pollution of the energy poor cave waters is favourable to their inhabitants, it may enable invaders from the surface to outcompete troglomorphic specialists in sinking rivers. Conservation of cave species is very demanding, since it requires protection of the whole drainage areas on the surface. Von ungefahr 12.600 im Jahre 1978 registrierten aquatischen Tierarten in Europa, waren mindestens 200 fakultative Hohlenbewohner und etwa 1.000 Arten (1998 schon 2.000 Taxa), also 8%, waren spezialisierte Stygobionten. Mehr als die Halfte davon sind Krebsarten (Crustacea). Zwei Hauptfaktoren ermoglichen vermutlich die relativ hohe Zahl der unterirdischen Krebsarten: (1) die Abwesenheit der kompetierenden Insekten und (2) eine kleinraumliche Einteilung der Verbreitungsareale (wass eine allgemeine Folge des hohen Endemismus der Stygobionten Arten, nicht nur der Krebse, ist). Slovenien hat mit etwa 200 Stygobionten Taxa auf einer Flache von 20.000 km2 die hochste bekannte Arten-Dichte und das Dinarische Gebiet hat mit fast 400 Taxa auf einer Flache von 153.400 km2 die artenreichste Stygofauna der Welt. Diese Verhaltnisse sind auch bei den terrestrischen Hohlenfaunen ahnlich. Der Artenreichtum der Crustacea ist vor allem eine Folge der okologischen und morphologischen Differenzierung innerhalb einiger Gattungen (z.B. Niphargus, Proasellus, Monolistra). Weiterhin sind aber auch hohere Taxa (Familien, Ordnungen) zahlreich vertreten. Nebst einiger nicht spezialisierten (Neu-)Einwanderer in unterirdische Habitate gibt es auch isolierte Populationen einiger ubiquistischen Arten (z.B. Asellus aquaticus, Synurella ambulans), die schon teilweise troglomorph sind. Unterirdische Arten sind bedroht durch Urbanisierung und andere Nutzungsformen der empfindlichen Karst-Landschaft. Obwohl eine leichte organische Verunreinigung der nahrstoffarmen Hohlengewasser fur ihre Einwohner gunstig ist, erleichtert sie in Sickerflussen das eindringen epigaischer Arten, die troglomorphe Spezialisten verdrangen konnen. Der Schutz von Hohlenarten ist ein anspruchsvolles Vorhaben, dass den Schutz ganzer Gewassersysteme an der Oberflache erfordert.
29
Chadwick, Austin J., Michael P. Lamb, and Vamsi Ganti. "Accelerated river avulsion frequency on lowland deltas due to sea-level rise." Proceedings of the National Academy of Sciences 117, no. 30 (July 13, 2020): 17584–90. http://dx.doi.org/10.1073/pnas.1912351117.
Анотація:
Sea-level rise, subsidence, and reduced fluvial sediment supply are causing river deltas to drown worldwide, affecting ecosystems and billions of people. Abrupt changes in river course, called avulsions, naturally nourish sinking land with sediment; however, they also create catastrophic flood hazards. Existing observations and models conflict on whether the occurrence of avulsions will change due to relative sea-level rise, hampering the ability to forecast delta response to global climate change. Here, we combined theory, numerical modeling, and field observations to develop a mechanistic framework to predict avulsion frequency on deltas with multiple self-formed lobes that scale with backwater hydrodynamics. Results show that avulsion frequency is controlled by the competition between relative sea-level rise and sediment supply that drives lobe progradation. We find that most large deltas are experiencing sufficiently low progradation rates such that relative sea-level rise enhances aggradation rates—accelerating avulsion frequency and associated hazards compared to preindustrial conditions. Some deltas may face even greater risk; if relative sea-level rise significantly outpaces sediment supply, then avulsion frequency is maximized, delta plains drown, and avulsion locations shift inland, posing new hazards to upstream communities. Results indicate that managed deltas can support more frequent engineered avulsions to recover sinking land; however, there is a threshold beyond which coastal land will be lost, and mitigation efforts should shift upstream.
30
Parker, Albert. "Anthropogenic Drivers of Relative Sea-Level Rise in the Mekong Delta – A Review." Quaestiones Geographicae 39, no. 1 (March 31, 2020): 109–24. http://dx.doi.org/10.2478/quageo-2020-0009.
Анотація:
AbstractThe Mekong Delta is sinking and shrinking. This is because of the absolute sea-level rise, and because of the subsidence of the land. The absolute sea-level rise originates from the thermal expansion of the ocean waters and the melting of ice on land, plus other factors including changes in winds and ocean circulation patterns. The subsidence originates from the construction of dams in the river basin upstream of the Delta, that has dramatically reduced the flow of water and sediments, and excessive groundwater withdrawal, plus other factors including riverbed mining, infrastructural extension, and urbanization. The origin of alluvial delta created by a continuous supply of water and sediments and the natural subsidence of uncompacted soils is relevant background information to understand the current trends. Another factor affecting the sinking and shrinking include the degradation of the coastal mangrove belt. It is concluded that the subsidence due to the reduced flow of sediments and water, and the withdrawal of groundwater more than the replenishment of aquifers is more than one order of magnitude larger than the absolute sea-level rise estimated by satellite and climate models, or the value estimated from tide gauges, that is much less. The current sinking and shrinking trends are not sustainable, as the low-lying Delta may disappear before the end of this century.
31
Khalil, Syed, and Richard Raynie. "CHALLENGES AND STRATEGIES FOR ECOSYSTEM RESTORATION OF A SINKING DELTA PLAIN." Coastal Engineering Proceedings, no. 36 (December 30, 2018): 26. http://dx.doi.org/10.9753/icce.v36.risk.26.
Анотація:
Coastal erosion is a major global problem and is most acutely felt along developed coastal areas where coastal communities and infrastructures are threatened by storm surge flooding. This situation gets compounded to a bigger challenge around most of delta plains which are rapidly subsiding. The degree and magnitude of challenges associated with erosion and submergence along muddy deltaic coasts is intricately related to population density. It is estimated that about 500 million people in the world live on river deltas (Syvitski et al., 2009). Coastal populations and their associated industries/economies (oil & gas, fisheries, port and commerce etc.) are thus threatened by rapid degradation of the deltaic landscapes. This situation is further complicated by sea level rise and high-energy events such as hurricanes (cyclones, typhoons).
32
Yapa, Poojitha D., Hung Tao Shen, and Keerthisri Angammana. "MODELING OIL SPILLS IN RIVER-LAKE SYSTEMS." International Oil Spill Conference Proceedings 1993, no. 1 (March 1, 1993): 611–16. http://dx.doi.org/10.7901/2169-3358-1993-1-611.
Анотація:
ABSTRACT A general model shell, ROSS3, simulates oil spills in complex river systems and has features that have not been available previously in oil spill models. The new approach has several advantages: It uses a time-varying boundary-fitted coordinate system that allows accurate accounting for a complex river/lake boundary as well as river boundary changes as water levels fluctuate; it can confine two-dimensional hydrodynamic computations to a limited region of the river; and, in addition to the traditional data entry and visualization interfaces, it can interactively lay out the channel networks for setting up the model and define extra cross sections to increase accuracy. ROSS3 is a two-layer two-dimensional oil spill model that can simulate the mechanisms of advection, horizontal diffusion, mechanical spreading, shoreline deposition, evaporation, dissolution, vertical mixing, resurfacing, and sinking. Both free surf ace and ice cover conditions can be simulated. In this study, ROSS3 is applied to the environmentally sensitive area of the St. Clair River, where the river branches into multiple channels before entering Lake St. Clair, and to the lake.
33
Cruden, D. M., A. E. Peterson, S. Thomson, and P. Zabeti. "Thirty-five years of activity at the Lesueur landslide, Edmonton, Alberta." Canadian Geotechnical Journal 39, no. 1 (February 1, 2002): 266–78. http://dx.doi.org/10.1139/t01-088.
Анотація:
The Lesueur landslide occurred on 3 September 1963 on the outside of a meander of the North Saskatchewan River in northeast Edmonton. The displaced volume was 0.76 Mm3 of Pleistocene deposits and underlying Upper Cretaceous mudstones. The trigger of the landslide is believed to be accelerated erosion of the slope toe caused by dumping of mine waste on the inside of the meander. Surveys in 1964, 1971, 1992, 1995, 1997, and 1998 have documented continued slope movements. The main scarp grew in height from 7.5 m on 4 September 1963 to 13.9 m in 1995 but retrogressed only 3 m. The displaced material extended up to 24 m into the North Saskatchewan River. When the forward motion of the passive block of the translational slide ceased to be driven by the sinking of the active block, river erosion caused rotational sliding of the displaced material on the surface of separation.Key words: landslide, Edmonton, Cretaceous, mudstone, erosion, North Saskatchewan River.
34
Quinif, Yves, and Richard Maire. "Pleistocene Deposits in Pierre Saint-Martin Cave, French Pyrenees." Quaternary Research 49, no. 1 (January 1998): 37–50. http://dx.doi.org/10.1006/qres.1997.1939.
Анотація:
Pleistocene deposits in alpine Pierre Saint-Martin cave are preserved in an abandoned river gallery. The deposits, 300 m long and 25 m high, are composed of a lower unit of fallen blocks overlain by debris flows, a main unit of laminated clay, and a series of river terraces inset into these units. The lower and main units are each overlain by speleothems. The lower unit represents a cold period, probably isotope stage 10. Corroded speleothems above it have given U/Th ages greater than 300,000–330,000 yr B.P. The main unit, with carbonate-rich varves devoid of pollen, represents a glaciation that occurred before 225,000 yr B.P. and probably correlates with stage 8, even though such a glaciation has not been previously recognized in the Pyrenees. The river terraces, covered by many noncorroded speleothems, probably formed during stage 7 (U/Th ages between 194,000 and 211,000–225,000 yr B.P.). Subsequent sinking of an underground river protected the deposits from erosion.
35
Guo, Shujin, and Jun Sun. "Concentrations and sinking rates of transparent exopolymer particles (TEPs) in a coastal sea: the Changjiang River (Yangtze River) Estuary." Acta Oceanologica Sinica 39, no. 10 (October 2020): 58–69. http://dx.doi.org/10.1007/s13131-020-1660-7.
36
Shi, Zimo, Jianming Zhang, Haijun Wu, Jing Yang, and Maolin Hu. "Taxonomic diversity pattern and composition of fish species in the upper reaches of Ganjiang River, Jiangxi, China." PLOS ONE 15, no. 11 (November 16, 2020): e0241762. http://dx.doi.org/10.1371/journal.pone.0241762.
Анотація:
Maintaining fish diversity is essential for environmental protection. To characterize the fish composition of the tributaries and mainstream in the upper reaches of the Ganjiang River, we identified seventy-five species of 15 families in 14 sampling sites. These data were analyzed using the inclusion index at the taxonomic level (TINCLi), the importance value index (IVI), the taxonomic diversity indices (Δ+ and Λ+), cluster analysis and non-metric multidimensional scaling (nMDS). The results showed that the most common and dominant order was the Cypriniformes, represented most frequently by Hemiculter leucisculus among the sample sites. Most fishes were omnivorous, mountain stream or settled fish that lay sinking or viscid eggs. Most sites showed a trend of more discrete distribution from high latitude to low latitude. According to the taxonomic diversity indices, the fish taxonomic composition in the upper reaches of Ganjiang River is uneven. The Bray-Curtis resemblance matrix and nMDS showed that the habitats of the Ganjiang River were divided into four areas. The results will provide information needed for freshwater fish resource protection in the upper reaches of the Ganjiang River.
37
Zini, L., C. Calligaris, and E. Zavagno. "Classical Karst hydrodynamics: a shared aquifer within Italy and Slovenia." Proceedings of the International Association of Hydrological Sciences 364 (September 16, 2014): 499–504. http://dx.doi.org/10.5194/piahs-364-499-2014.
Анотація:
Abstract. The classical Karst transboundary aquifer is a limestone plateau of 750 km2 that extends from Brkini hills in Slovenia to Isonzo River in Italy. For 20 years, and especially in the last two years, the Mathematic and Geosciences Department of Trieste University has run a monitoring project in order to better understand the groundwater hydrodynamics and the relation between the fracture and conduit systems. A total of 14 water points, including caves, springs and piezometers are monitored and temperature, water level and EC data are recorded. Two sectors are highlighted: the southeastern sector mainly influenced by the sinking of the Reka River, and a northwestern sector connected to the influent character of the Isonzo River. Water table fluctuations are significant, with risings of > 100 m. During floods most of the circuits are under pressure, and only a comparative analysis of water levels, temperature and EC permits a precise evaluation of the water transit times in fractured and/or karstified volumes.
38
Dott, Robert. "Lyell in America—His Lectures, Field Work, and Mutual Influences, 1841-1853." Earth Sciences History 15, no. 2 (January 1, 1996): 101–40. http://dx.doi.org/10.17704/eshi.15.2.b4n1102556ju6736.
Анотація:
Charles Lyell visited North America four times in the twelve years from 1841 to 1853. Except for the last visit, he both lectured and travelled widely to study geology. In 1841 he opened the second season of Lowell Lectures in Boston, and in early 1842 he gave essentially the same lectures again at Philadelphia and New York. In 1845 and 1852, Lyell lectured only at Boston. In 1853, he returned briefly as a British representative at the New York Industrial Fair. The New York lectures were published verbatim, and Lyell's incomplete notes for his lectures, newspaper accounts, and his wife Mary's correspondence from America provide some insight about the others. During 25 months of travel spanning a dozen years, the Lyells saw more of the United States and southeastern Canada—from the Atlantic coast to the lower Mississippi and Ohio Rivers and from the St. Lawrence Valley to the Gulf Coast—than had most citizens of the New World. After the first two visits, Lyell published two travel journals, which contain much material about American geology, geologists, and general natural history, as well as perceptive commentaries upon most aspects of life in the two young nations. The lectures and journals together provide important insights into the development of geology in America and of Lyell's thinking. In spite of the fact that Lyell was a poor speaker, the lectures were great successes with the public. American geologists, however, gave more qualified assessments. Major topics covered by the lectures, which reflected the major current issues of the science, included during an eleven-year span: Crustal movements and the earth's interior; Uniformity of processes through geologic time; Coral reefs; Carboniferous conditions and coal formation, as well as the early appearance of land animals; Origin of the drift and the Sinking and submergence of land; Biogeography; and the Uniformity of an organic plan, including negative commentary about progression and transmutation. Lyell's use of examples from both America and abroad gave the subject a cosmopolitan aspect, and his use of many large diagrams was much acclaimed. Geology was becoming well established in the New World, and Lyell participated in the third annual meeting of the American Association of Geologists and Naturalists in 1842. For field work, he followed his well-honed tactic of seeking experts as guides for efficient learning about local geology and grilling them incessantly. Although initially enthused and open, American geologists soon became apprchensive about Lyell's acquisitiveness for their data. Eventually Lyell's bibliography was enhanced by more than 30 titles on American geology in addition to two travel books, the first of which included a colored geologic map of most of the then United States and adjacent Canada. His other books, Principles of Geology and Elements of Geology, also benefited from countless American examples and from the publication of American editions. Lyell's reputation was enhanced by his American adventures, for, like Darwin and Murchison before, his travels attracted much attention both in the London Geological Society and in the British press. But the visits also enhanced the stature of geology in the New World, and Lyell made several significant original contributions to the understanding of American geology. Moreover, the visits by Charles and Mary Lyell produced a positive impression of America abroad, for they were very captivated by their friendly and industrious hosts and spoke well of them in Britain. On balance, it would seem that the visitors and hosts benefitted about equally.
39
Pratt, Anna C., and Jessica Templeman. "Jurisdiction, Sovereignties and Akwesasne: Shiprider and the Re-Crafting of Canada-US Cross-Border Maritime Law Enforcement." Canadian Journal of Law and Society / Revue Canadienne Droit et Société 33, no. 3 (December 2018): 335–57. http://dx.doi.org/10.1017/cls.2018.26.
Анотація:
AbstractAgainst the historical backdrop of the sinking of the Canadian rum-running schooner theI’m Aloneby the US Coast Guard in 1929, this paper examines the re-crafting of maritime jurisdictional practices in the 2000s through the Canada-US Cross-Border Maritime Law Enforcement Program known as Shiprider. Thinking jurisdictionally and taking seriously the materiality of the water, we explore the significance of Shiprider’s patrols in the local context of Kaniatarowano’on:we (St. Lawrence River) which flows through Akwesasne Mohawk Territory, an indigenous border nation cleaved by the Canada-US international border where local communities contend with and continue to refuse imposed colonial settler boundaries.
40
S. Intan, M. Fadhlan. "Geologi Situs Paleolitik Pacitan Bagian Timur Kabupaten Pacitan, Provinsi Jawa Timur." AMERTA 26, no. 1 (February 24, 2020): 1–22. http://dx.doi.org/10.24832/amt.v26i1.1-22.
Анотація:
Abstract. The Geology of the Paleolithic Site of the Eastern Part of Pacitan, Pacitan Regency, East Java Province. The Paleolithic Site of the Eastern Part of Pacitan is located at Km-10 to Km-18 east of the city of Pacitan to the direction of Trenggalek regency. It covers three main rivers, namely Kedunggamping (Padi) River, Ngrendeng-Tulakan River, and Lorog River. The site has lowland, weak wavy, strong wavy, and karst morphological units. It is situated at an elevation of O - 900 m above sea level. The three rivers that flow in this area are old and old-mature stadium ones, with observable trellis and rectangular desiccated patterns. They belong to periodic, consequent, and subsequent types. The rocks that compose the area are volcanic breccia, conglomerate, ingenous rock unit, sand stone, tuff, clay-stone, silt, limestone unit, and alluvial sediment, with ages that range from Oligocene up to Holocene. The geological structures that are found in this place include sincline fold and strike slip. The river terraces belong to the first, which still directly connected to the river surface. Disturbance on geological structure is one of the factors that influence the position and existence of the river terraces. Lithic tools made of chert, andesite, jasper, silicified-limestone, wood fossil, chalcedony, and limestone are found at this site. The raw materials of those tools (granule, pebbles, and boulders) are usually available along the rivers.Abstrak. Lokasi Situs Paleolitik Pacitan bagian Timur terletak di Km-10 hingga Km-18 sebelah timur Kota Pacitan ke arah Kabupaten Trenggalek. Situs Paleolitik ini meliputi wilayah Sungai Kedunggamping (Sungai Padi), Sungai Ngrendeng-Tulakan, dan Sungai Lorog. Bentang alam wilayah situs ini termasuk pada satuan morfologi dataran, satuan morfologi bergelombang lemah, satuan morfologi bergelombang kuat, dan satuan morfologi karst. Ketinggian situs berada pada O - 900 meter di atas permukaan air laut. Ketiga sungai itu termasuk pada sungai berstadia Tua (old river stadium) dan Dewasa-Tua (old-mature), dengan kenampakan pola pengeringan Trellis dan Rectangular. Selain itu, termasuk pada Sungai Periodis, Sungai Konsekuen, dan Sungai Subsekuen. Batuan penyusun wilayah situs adalah breksi vulkanik, konglomerat, satuan batuan beku, batu pasir, tufa, batu lempung, batu lanau, satuan batu gamping, dan endapan aluvial. Kisaran umurnya ialah dari Oligosen hingga Holosen. Struktur geologi yang melewati wilayah situs adalah Lipatan (fold) dari jenis sinklin, dan Patahan (fault) dari jenis sesar geser. Undak-undak sungai yang teramati termasuk pada undak sungai pertama yang masih berhubungan langsung dengan muka air sungai. Gangguan struktur geologi ikut mempengaruhi keletakan dan keberadaan undak-undak sungai itu sendiri. Alat-alat litik terdiri dari batuan chert, andesit, jasper, batugamping kersikan, fosil kayu, kalsedon, dan batugamping. Sumber bahan baku alat-alat litik tersebut umumnya berada di alur-alur sungai dalam bentuk kerikil, kerakal, dan boulder batuan.
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Devy, Shalaho Dina. "Pemodelan airtanah dan Neraca Airtanah Dampak Penambangan Batubara Open Pit pada Lipatan Sinklin di Daerah Muara Lawa, Kabupaten Kutai Barat, Provinsi Kalimantan Timur." SPECTA Journal of Technology 2, no. 2 (November 27, 2019): 69–83. http://dx.doi.org/10.35718/specta.v2i2.108.
Анотація:
Ch a n g e s in land use impacts on groundwater availability both in quality and quantity. Study of geological, hydrogeological conditions, hydrological, hydrogeological boundary conditions contribute to determine the presence of groundwater in the groundwater basin and determine the natural groundwater flow modeling patterns. Location of the study are in Muara Lawa, including the formation Pulaubalang, Pamaluan, and Balikpapan on Lampanan syncline structure. Exploration drilling results indicate, that the hydrogeological study area into the aquifer system of folded sedimentary rocks consisting of seven aquifer layers alternating between akuitar, aquifers, and the base layer in the form of akuiklud. The area bounded by the limits of the model study of surface water in two major rivers, the Lawa River (east) and the Perak River (west), as well as the groundwater divide with the highest head (north and south. The results of the analysis of the type of regional aquifers aquifer models including the category of semi depressed with aquitards dominance in the surface layer. The pattern of groundwater flow and head height can be predicted by modeling using Visual Modflow. There is an increase zone budget is almost five times higher than the natural condition to the active mining conditions, particularly in the green zone, that of the natural conditions of 1,502 m3 day-1 to 12,930 m3 day-1 in the active mining. This is due, in the mining area there is a change in land use and hidrostratigrafi, namely the formation of pits that reach depths of 70 meters.
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Zúñiga, Diana, Celia Santos, María Froján, Emilia Salgueiro, Marta M. Rufino, Francisco De la Granda, Francisco G. Figueiras, Carmen G. Castro, and Fátima Abrantes. "Diatoms as a paleoproductivity proxy in the NW Iberian coastal upwelling system (NE Atlantic)." Biogeosciences 14, no. 5 (March 13, 2017): 1165–79. http://dx.doi.org/10.5194/bg-14-1165-2017.
Анотація:
Abstract. The objective of the current work is to improve our understanding of how water column diatom's abundance and assemblage composition is seasonally transferred from the photic zone to seafloor sediments. To address this, we used a dataset derived from water column, sediment trap and surface sediment samples recovered in the NW Iberian coastal upwelling system. Diatom fluxes (2.2 (±5.6) 106 valves m−2 d−1) represented the majority of the siliceous microorganisms sinking out from the photic zone during all studied years and showed seasonal variability. Contrasting results between water column and sediment trap diatom abundances were found during downwelling periods, as shown by the unexpectedly high diatom export signals when diatom-derived primary production achieved their minimum levels. They were principally related to surface sediment remobilization and intense Minho and Douro river discharge that constitute an additional source of particulate matter to the inner continental shelf. In fact, contributions of allochthonous particles to the sinking material were confirmed by the significant increase of both benthic and freshwater diatoms in the sediment trap assemblage. In contrast, we found that most of the living diatom species blooming during highly productive upwelling periods were dissolved during sinking, and only those resistant to dissolution and the Chaetoceros and Leptocylindrus spp. resting spores were susceptible to being exported and buried. Furthermore, Chaetoceros spp. dominate during spring–early summer, when persistent northerly winds lead to the upwelling of nutrient-rich waters on the shelf, while Leptocylindrus spp. appear associated with late-summer upwelling relaxation, characterized by water column stratification and nutrient depletion. These findings evidence that the contributions of these diatom genera to the sediment's total marine diatom assemblage should allow for the reconstruction of different past upwelling regimes.
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Reckel, Johannes. "Реформы современного ойрат-калмыцкого языка и литературы в XX веке". Монголоведение (Монгол судлал) 12, № 3 (5 листопада 2020): 349–69. http://dx.doi.org/10.22162/2500-1523-2020-3-349-369.
Анотація:
Introduction. The Oirats are Western Mongols, today living between the Altai mountains, the river Volga, the Kukunor Area, the Ili River and Kyrgyzstan. In 1648, Zaya Pandita from the Hoshut (Hoshud) tribe of the Oirats created the ‘Clear Script’ (Oir. Todo Bičig), nowadays also known as Oirat Script. This script was originally meant to be used as a reformed script by all Mongols, but it caught on with the Western Mongols, the Dzungars (Oirats, Kalmyks), only. The 20th century witnessed the introduction of new writing standards for individual groups of Oirats/Kalmyks in the Soviet Union (Russia), China and Mongolia, which led to a weakening of the West Mongolian identity. Three of the most influential Kalmyk scholars, who worked on the reform of the written language and who were active as teachers and researchers in Tashkent, Sinkiang and Western Mongolia in the 1920s and 1930s, were Aksen Suseev, Iǰil Čürüm and Ceren Dorži Nominhanov. Goals. The study aims to investigate the connection between ethnic identity and (written) language against the background of global political upheavals. The work focuses on the change of the Oirat written language in Sinkiang (Xinjiang) in a multi-ethnic region compared to the Kalmyk written language in Russia, as well as the Oirat language in Mongolia over the past 100 years. Materials. The research project, given as an outline in the following article, analyzes schoolbooks, dictionaries, grammars and other printed materials of the 20th and 21st centuries in the West Mongolian Oirat script collected in Sinkiang Kalmykia since 1986. Results. Since the 1940s, the Oirats in Sinkiang have been taking up a development in their reformed written language that was originally initiated in Kalmykia by Kalmyk scholars during the period of 1915–1938, but was not carried on there due to the political conditions which resulted in the deportation of the Kalmyks to Siberia in 1943. After the return of the Kalmyks to Kalmykia since 1957/58 the old traditions were broken, and the development of the written language focused solely on the use of a modified Cyrillic alphabet. The community based on a common script of the Kalmyks and Oirats – in China, Russia (Kalmykia) and Western Mongolia – broke up, and the three or four groups went their separate ways. For example, the orthography and grammar of the Oirat written language in reformed Todo Bičig in Sinkiang is not standardized until today. The Oirats in Mongolia, like the Oirats in Kyrgyzstan, no longer have their own written language in which they can express themselves in writing. Another desideratum is a textbook of modern Kalmyk and modern Sinkiang Oirat for Western students and scholars. Although some institutions and scholars have some Oirat language archives, like the State and University Library Goettingen has good collection of Kalmyk-Oirat and Mongolian literature, there are a lot of aspects to deal with.
44
Juul-Pedersen, Thomas, Christine Michel, and Michel Gosselin. "Influence of the Mackenzie River plume on the sinking export of particulate material on the shelf." Journal of Marine Systems 74, no. 3-4 (December 2008): 810–24. http://dx.doi.org/10.1016/j.jmarsys.2008.02.001.
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Silliman, Benjamin Douglas. "Guidelines to Prepare for Oil Sands Product Spills in Varied Aquatic Environments." International Oil Spill Conference Proceedings 2014, no. 1 (May 1, 2014): 426–33. http://dx.doi.org/10.7901/2169-3358-2014.1.426.
Анотація:
ABSTRACT On July 24, 2007, the Westridge Transfer Line in Burnaby, British Columbia, ruptured spilling 1,400 barrels of oil sands product into the area's storm water systems and eventually into the Burrard Inlet at Vancouver Harbor. The response to this spill was considered successful and there is no record of oil sinking. Several years later, in July of 2010, the Line 6B pipeline operated by Enbridge Energy Partners LLP ruptured spilling 20,082 barrels of oil sands product into the Kalamazoo River. In contrast to the Burnaby spill, this response was extremely difficult due to the sinking of large quantities of oil. The variance in fate and behavior of the oil sands products in these two spills demonstrates how environmental factors can result in different response challenges. Many environmental factors affect the fate of spilled oil sands products in aquatic environments because bitumen, a large component of oil sands products, has a density greater than freshwater. By analyzing specific factors in areas at risk, responders can better prepare for, and expect, submergence in oil sands product spills. Areas identified to have low salinity, rough sedimentation, high turbidity, strong sunlight exposure, high temperatures, and strong currents have a high risk of submergence. Response teams in these areas of high risk should have submerged oil recovery equipment readily available for rapid deployment.
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SOLOVEY, Tatiana, and Rafał JANICA. "ASSESSMENT OF THE IMPACT OF WATER PUMPING FROM DEPRESSION AREAS ON THE WATER CONDITIONS OF NATURA 2000 PEATBOG “UROCZYSKA W LASACH STEPNICKICH” BASED ON HYDRODYNAMIC MODELLING." Biuletyn Państwowego Instytutu Geologicznego 471 (October 1, 2018): 159–70. http://dx.doi.org/10.5604/01.3001.0012.5054.
Анотація:
Both the lack of a continuously functioning drainage system and the neglect of the drainage infrastructure result in restoration of natural sinking processes in depression areas on the eastern side of the Odra River estuary and the Szczecin Lagoon. Persistent restoration of natural habitats can be observed in these areas. The impact of water pumping at depression areas on the dynamics of the first (shallow) aquifer was analysed in the Natura 2000 site called “Uroczyska w Lasach Stepnickich PLH320033”. Simulation of the impact of water pumping on lowering of groundwater levels based on hydrodynamic modelling shows that the minimum groundwater level variations in the depression range occur only in a small southern part of the area, and the impact is of short-term nature. The basic factor affecting shallow groundwater in the analysed area is the water table level in the Odra River. The threat to natural habitats, especially in the “Uroczysko Święta” reserve, is associated with their progressive flooding, which occurs as a result of a systematic decrease in the amount of water being pumped.
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Prat, Narcís, and Carles Ibañez. "Effects of water transfers projected in the Spanish National Hydrological Plan on the ecology of the lower River Ebro (N.E. Spain) and its delta." Water Science and Technology 31, no. 8 (April 1, 1995): 79–86. http://dx.doi.org/10.2166/wst.1995.0268.
Анотація:
This paper refers to the effects of projected water transfers, envisaged in the Spanish National Hydrological Plan, on the ecology of the lower River Ebro and its delta. Present management strategies, have resulted in highly eutrophic river water and a salt wedge which runs for more than 30 km upstream from the river mouth and its presence has been recorded during most of the year. Some parts of the delta coast are in regression as most of the inorganic sediments carried by the river are trapped in the dams. This is also leading to the sinking of the deltaic plain because subsidence and eustatic sea level rise are not compensated by new sediments. The high productivity of two bays and the coastal zone adjacent to the delta is related to influx of freshwater from irrigation channels, used in rice cultivation and the river. In the new National Hydrological Plan, a withdrawal of water upstream from the delta of 2012 hm3/year (15% of the mean annual discharge) is planned as well as the construction of 49 new reservoirs, mainly for irrigation purposes. A minimum river flow of 100 m3/s will be established by the Plan. If the plan is carried through, due to the water abstraction, forecasts based on ecological studies in the area predict: (1) increased presence of the salt wedge in the final 18 km of the river with detrimental effects on river fauna and flora; (2) serious threats to aquaculture and fisheries in the bays; (3) reduction of fish and crayfish production in the platform area; (4) further reductions in sediment and freshwater inputs to delta; (5) salinization of fields under cultivation; and (6) detrimental side effects on deltaic ecosystems.
48
Valente, Ettore, Antonio Santo, Domenico Guida, and Nicoletta Santangelo. "Geotourism in the Cilento, Vallo di Diano and Alburni UNESCO Global Geopark (Southern Italy): The Middle Bussento Karst System." Resources 9, no. 5 (April 26, 2020): 52. http://dx.doi.org/10.3390/resources9050052.
Анотація:
In this paper we want to stress the role of geotourism as a means to promote environmental education and, on occasion, as a way to increase the touristic interest of an area. Geoparks are certainly the territory where geotourism can be best exploited. We propose a geoitinerary to discover the amazing, but poorly known, Middle Bussento Karst System, with the blind valley of the Bussento River, in the southeast of the Cilento, Vallo di Diano and Alburni United Nations Educational, Scientific and Cultural Organization (UNESCO) Global Geopark. This is the only example, in Southern Italy, of a stream sinking underground and it is the second longest subsurface river path in Italy, making this a core area of the Geopark. We combined field surveys and literature data to create a geoitinerary that can be useful in helping to promote this site. This geoitinerary is applicable to both simple generic visitors and geo-tourists and has an educational purpose, especially in explaining the significance and the fragility of karst areas in terms of environmental protection. Moreover, it may represent a sort of stimulus for the growth of touristic activity in this inner area of the Geopark.
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Tang, Xiaowu, Jiaxin Liang, Wei Liu, Yuhang Ye, Penglu Gan, Wenfang Zhao, and Yue Yu. "Modification of Peck Formula to Predict Ground Surface Settlement of Twin Tunnels in Low Permeability Soil." Advances in Civil Engineering 2021 (February 24, 2021): 1–13. http://dx.doi.org/10.1155/2021/6698673.
Анотація:
Accurate prediction of surface settlement induced by tunnel excavation is significant for preventing damage to existing structures under complex geological conditions. The Peck formula is currently considered as an efficient solution for surface settlement prediction. This paper proposes a modified Peck formula considering geological conditions to improve the accuracy of surface settlement prediction of twin tunnels. The asynchronization of the sinking rate and stability of the vault settlement and surface settlement within the river-affected area may attribute to the groundwater drawdown caused by cofferdam construction on the river. A modified Peck formula is put forward with soil permeability and width-controlling parameters involved. There is a small settlement at the center of the twin tunnels, making the settlement trough upward buckling, which is like a “W” shape. This situation can be accurately predicted by the modified formula with a significantly increased adjusted R-square. The modified formula can accurately predict the surface settlement of tunnels excavated in low permeability soil layers with a permeability coefficient between 10−4 cm/s and 10−7 cm/s, especially in the groundwater drawdown environment. The reliability of the modified Peck formula is verified by other cases in Nanjing and Singapore.
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ZHOU, Qiu-Bai, Yu ZHENG, Li ZHOU, and Jian-Fang GUI. "GENETIC DIVERSITY OF CRUCIAN CARP (CARASSIUS AURATUS) FROM YILI RIVER OF SINKIANG DISTRICT." Acta Hydrobiologica Sinica 33, no. 4 (August 5, 2009): 690–95. http://dx.doi.org/10.3724/sp.j.1035.2009.40690.