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New Approach for Estimation of Natural and Anthropogenic Components in the Recent Tendencies of Erosion Intensity and Suspended Sediment Yield Changes in River Basins
A.V. Gusarov
Iranian Journal of Earth Sciences , 2010,
Abstract: The offered approach is based on the establishment of the functional dependence between river water discharge (Q) and suspended ms ,in a number of observations, which noticeably differs from the mean value (R) of subsequent allocated period(s). The earliest period anthropogenic component during the subsequent period(s) is the difference between an actual suspended sediment yield and its hypothetical value, which is connected only with changes of natural (mainly, hydro-climatical) factors without any anthropogenic changes of geographical (erosive) conditions in a river basin. This hydro-climatical component is calculated by extrapolation of an me for subsequent period(s). Approbation of the offered approach is made on the examples of some rivers (Zapadny Bug (Ukraine), Magdalena (Colombia), Bei-Nan (Taiwan, China), Sanchuanhe (China) and Indus (India, Pakistan, China).
Changes of the intensity of Ljig river basin erosion: Influence of anthropogenic factor  [PDF]
Dragi?evi? Slavoljub,Stepi? Milomir
Glasnik Srpskog Geografskog Dru?tva , 2006, DOI: 10.2298/gsgd0602037d
Abstract: According to new field investigations as well as mapping of erosion in Ljig river basin we have found out that its intensity has changed in regard to period of 40 years ago. The most expressive changes were noticed in Ljig river basin. As we have not noticed changes in physical-geographical factors the cause of the intensity decrease might be only influenced by indirect anthropogenic factor. Processes of growing old and decrease of rural population, migration village-town, marginalization of agriculture and decrease of cattle reserves caused the changes of land utilization. Agriculture areas were becoming overgrown with growing wild vegetation which restrained gradually considerable expressed processes of erosion in the past.
ANTHROPOGENIC INFLUENCE ON FLOW AND SEDIMENT REGIME OF A RIVER BASIN  [PDF]
BALESHWAR SINGH,R. K. GOSWAMI
International Journal of Engineering Science and Technology , 2012,
Abstract: The Brahmaputra river basin in India is at present undergoing rapid agricultural, industrial and economic development with more than 30 million people living within this part of the major basin. The presentstudy examines impacts of some of the anthropogenic activities that are responsible for the disturbances to the flow and sediment regime as well as to the biogeochemical flux of nutrients through the river. The study also throws light on some aspects of the climatic change of the north-eastern region of India in particular, because of the considerable effect of the monsoon over the flow regime of the river.
Proposed Relief Map of the Suitability of the Maranh?o River Basin, Brazil, for Anthropogenic Use  [PDF]
Valdir A. Steinke, Ercilia Torres Steinke, Mario Diniz Araujo Neto, Maria Ligia Cassol Pinto
Journal of Geographic Information System (JGIS) , 2016, DOI: 10.4236/jgis.2016.83030
Abstract: In this paper, we proposed a method for mapping the suitability of land for intensive anthropogenic use in the Maranhao River Basin, in the state of Goiás, Brazil. We analyzed existing 1:250,000 maps of the local geology, drainage system topography and geomorphological features. We generated new information based on our analysis, including a compilation of basic morphometric data and a map of the slopes in the basin, which we used to construct the geomorphological suitability map of the watershed. Our results indicate that 40% of the study area can support intensive anthropogenic use; the remaining 60% of the basin area is categorized as “fragile” regarding the expansion of intensive land use.
Geomorphological Effects of River Valleys Anthropogenic Transformations in the Perznica Catchment During the Last 200 Years (Drawsko Lakeland, Pars ta River Basin)
Józef Szpikowski
Quaestiones Geographicae , 2011, DOI: 10.2478/v10117-011-0010-4
Abstract: The studies on geomorphological aspects of environmental changes in the river valleys were part of the work carried out under the diagnosis of anthropogenic transformation of the relief of the Perznica basin (West Pomerania, Drawsko Lakeland). Human interference in the river valleys and anthropogenic changes in the natural hydrological systems in the Perznica catchment influenced the transformation of the relief and the intensity of morphogenetic processes. Numerous anthropogenic landforms were formed, including embankments, dams, dykes along the canals, ditches and canals, reservoirs basins, and peat excavations. The drainage resulted in an intensification of the river erosion, straightening, shortening and increase of the river gradient, as well as the increase of quantity of the suspended matter leaving the catchments. An increase of anthropogenic denudation on agricultural lands, due to the entering of the crops grown on drained depressions and valleys, led to the masking of the original relief with deluvial sediments and the formation and expansion of agricultural terraces on the edge of the fields.
Anthropogenic Pollution of Inland Waters: the Case of the Aboabo River in Kumasi, Ghana  [cached]
Leslie Danquah,Kabila Abass,Aristotle Afutu Nikoi
Journal of Sustainable Development , 2011, DOI: 10.5539/jsd.v4n6p103
Abstract: This study assessed the quality of the Aboabo River and examined the anthropogenic factors that lead to river pollution. Physico-chemical and bacteriological assessment of water samples showed that water from the Aboabo river was polluted and therefore not suitable for domestic consumption. Observation, in-depth interviews, informal conversation and a cross-sectional survey of 396 households in the river basin were employed to elicit qualitative and quantitative data. Direct anthropogenic factors identified were indiscriminate dumping of refuse, channelling of raw sewage, open defecation and indiscriminate dumping of industrial waste into the Aboabo River. Remote factors identified were population growth and institutional challenges. Recommendations made include enforcement of by-laws, provision of adequate sanitation facilities and the encouragement of opinion leaders to play an active role in promoting the inculcation of environmentally friendly practices amongst residents.
Influence of environmental variables and anthropogenic perturbations on stream fish assemblages, Upper Paraná River, Central Brazil
Araújo, Nicelly B.;Tejerina-Garro, Francisco L.;
Neotropical Ichthyology , 2009, DOI: 10.1590/S1679-62252009000100005
Abstract: the ouvidor river, a tributary of the upper paraná river, drains areas covered by cerrado vegetation in central brazil. we collected data for environmental variables (water temperature, dissolved oxygen, ph, conductivity, turbidity, water velocity, luminosity, channel substrate and width) and anthropogenic perturbations (industry, reservoirs, urban areas) that may structure the fish assemblage in ten stream sites of the ouvidor river basin. in each stream we delimited one 50 m long site where fish were captured by electrofishing and abiotic data were collected every two month between august 2004 and june 2005. co-inertia analysis indicated that ph, water velocity, channel width and water temperature most strongly structured the fish assemblages. the interactions of water velocity and channel width with the fish assemblage were not directly affected by wet and dry seasons but the opposite was true for ph and water temperature.
IDENTIFICATION OF ANTHROPOGENIC INFLUENCES ON WATER QUALITY OF JAKARA RIVER, NORTHWESTERN NIGERIA  [PDF]
ADAMU MUSTAPHA
Journal of Applied Sciences in Environmental Sanitation , 2012,
Abstract: Jakara River, northwestern, Nigeria has been found to be polluted by various sources of pollution associated with excessive land use. This study attempted to identify the sources of pollution in the Jakara Basin using principal component analysis and factor analysis (PCA/FA). Four different sampling points were designed along Jakara River and surface water samples were collected for sixty days. Fifteen physico-chemical parameters were analyzed which includes: water temperature, turbidity, salinity, conductivity, pH, nitrates (NO3-), ammonia-nitrate (NH3-NL), total solids (TS), suspended solids (SS), dissolved solids (DS), 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), dissolved oxygen (DO), phosphates (PO43-), and chloride (Cl). PCA/FA extracted five principal components (PCs) explaining 70.7% of the total variance of the raw data. PCA/FA showed that Jakara River is influenced mostly by organic and nutrients (anthropogenic) pollution from domestic wastewater and little contribution from geology of the area, erosion and farmland run-off. These results provide fundamental information for the authorities to take sound action for developing better water pollution control and effective management of river water quality in the area.
Reconstruction of Anthropogenic Impact Intensity Changes during Last 300 Years in Lake Engure Using Analysis of Sedimentary Records
Maris Klavins, Ilga Kokorite, Maruta Jankevica, Valerijs Rodinovs, Liga Dreijalte
Scientific Journal of Riga Technical University. Environmental and Climate Technologies , 2011, DOI: 10.2478/v10145-011-0029-8
Abstract: Environmental pollution with trace elements is considered as one of the most important environmental problems. Analysis of trace element accumulation in sedimentary phases of lakes may reflect the overall regional pollution level, but analysis of trace element accumulation patterns in sediment profiles can help to reconstruct the history of anthropogenic impacts. The aim of this study was to analyse trace element concentrations in the sediments of Lake Engure in Latvia and analyze factors influencing their availability. The metal concentrations in sediments of Lake Engure are at background levels, especially in comparison to metal concentrations in West European countries. However, analysis of element concentration changes in sedimentary profiles gives information about trends of recent accumulation (within the last 300 years) and the balance between natural and human induced accumulation processes.
EROSIVE PROCESSES IN URUCUTIUA RIVER BASIN: PA O DO LUMIAR TOWN – MA
Wanderson Barbosa Cirillo,Francicléia Vieira Ribeiro,Márcia Fernanda P. Gon?alves,Antonio Cordeiro Feitosa
Revista Sociedade & Natureza , 2005,
Abstract: The modeling of the terrestrial prominence is the result of the endogenous and exogenous agents, denominated as erosion agents, that constitute a set of forces that contribute to the soil erosion development and the prominence modeling that can be a risk to man according to the modifications of the humanized environment.In Brazil, the problem of erosion is old. The states of Parana, Sao Paolo and Rio Grande do Sul are the states that have the best exponents of control for these processes. In the rest of the country, the lack of interest of the government institutions results in absence of reference materials to detail the studies so that the planner have difficulties to understand the situation to prevent it.This study justifies itself because the area in question has been invaded without a compatible plan where we observe environmental problems in different frequencies and magnitudes whose the final product is the elaboration of the map of vulnerability to the erosive processes in Urucutiua river hydrography basin that will subsidize the redefinition of the process of local occupation that is inserted in area of high susceptibility to erosion according to Cirillo (2003, p. 50).
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