Watershed land use types as drivers of freshwater phytoplankton structure

Abstract Background The impact of watershed land-use on surface water quality is one of the under researched areas in mega cities of the developing countries like Addis Ababa. The study examined the impact of watershed land uses on the Kebena river water quality within its seasonal and spatial variation and assessed the relationship between river water pollution and dominant land-use types in the sub-watersheds. Method The main land use types in the sub-watersheds were digitized from aerial photograph of 2016, and quantified for water quality impact analysis. Water samples were collected from the main Kebena river and the three sub-watersheds source and outlet points. A total of 128 samples were collected during the dry and wet seasons of 2016 and 2017 and analyzed for various water quality parameters. The study employed ANOVA, independent t-tests and multiple regression analysis to examine variations in water quality and assess the influence of the different land uses on water quality. Results Forest, built-up area and cultivated lands are the three major land use types in the Kebena watershed accounting for 39.14, 32.51 and 27.25% of the total area, respectively. Kebena catchment is drained by three sub-watersheds namely, Denkaka (44.9% cultivated land), Little-Kebena (60.87% forested) and Ginfle (90.44% urban land). The concentration of pollutants in the Kebena river was significantly higher (P < 0.001) in the dry season than in the wet season. However, when compared to surface water quality standards, both the dry and wet season water quality records are exceptionally high. The urban and forest dominated sub-watersheds contribute significantly high amount of (P < 0.001) pollutant loads to the river which is associated with high runoff from impervious surfaces and sewerage discharge to the river from nearby urban settlements. Conclusion Integrating watershed planning with land use planning is of paramount importance to address water quality problems in urban areas. Thus, in the urban dominated sub-catchment, land-use planning should aim to relocating river front communities, providing sufficient river buffer-zones and forwarding appropriate storm water management schemes. In the forested sub-catchment, planning should protect, retain and enhance the existing natural green spaces through open space planning, and management schemes while providing wide river-buffer with natural vegetation cover to minimize pollution load to urban rivers from agriculture dominated sub-watershed.

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Effects of Urbanization on Stream Ecosystems

Effects of Urbanization on Stream Ecosystems ◽

10.47886/9781888569735.ch14 ◽

2005 ◽

Keyword(s):

Land Use ◽

Alien Species ◽

Fish Assemblage ◽

Southern California ◽

Fish Assemblages ◽

Fish Abundance ◽

Watershed Land Use ◽

Land Use Types ◽

Coastal Streams ◽

Assemblage Metrics

Abstract.—Data collected as part of two studies to examine the influences of landscape modification on the ecology of three coastal Southern California river systems—the Calleguas Creek, Malibu Creek, and Santa Clara River watersheds—provided the opportunity to examine relations between urbanization and fish assemblages in Southern California coastal streams. Fish were collected at 63 sites from 1999 to 2001. Watershed land use was determined and classified into three land use types: agriculture, developed, and open space. Seven fish assemblage metrics were examined, including species richness, number of native and alien species, total fish abundance, percent abundance of native and alien species, and percent abundance of arroyo chub Gila orcuttii. Ten fish species were collected, and arroyo chub was the only species collected in all three watersheds. Native species included arroyo chub, threespine stickleback Gasterosteus aculeatus, steelhead Oncorhynchus mykiss, and Pacific staghorn sculpin Leptocottus armatus. There were no significant differences in fish assemblage metrics among the three land-use types. Both wetted stream width and depth were significantly related to native fish abundance. Results from this study suggest that the relatively species poor fish assemblages of Southern California may not be sensitive to watershed land use disturbance, but may be sensitive to local hydrologic conditions.

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the Impact of Watershed Land Use on River Water Quality: Implication for Planning in the Case of Kebena River Watershed, Addis Ababa, Ethiopia

10.21203/rs.3.rs-87208/v1 ◽

2020 ◽

Author(s):

Kalkidan Asnake ◽

Hailu Worku ◽

Mekuria Argaw

Keyword(s):

Water Quality ◽

Land Use ◽

Surface Water Quality ◽

Quality Parameters ◽

Cultivated Land ◽

Water Quality Indicators ◽

Watershed Land Use ◽

Land Use Types ◽

Management Schemes ◽

The Impact

Abstract Background: The impact of watershed land-use on surface water quality, especially in urbanized areas, has been investigated in numerous studies in developed countries, however, the issue is one of the under researched areas in developing cities of Africa. To study the impact of watershed land-use on surface water quality, we used the main land use types of the Kebena watershed from aerial photograph and collected river water samples during the dry and wet seasons for two consecutive years at different points from the river course. We calculated the share of each land use using ArcGIS and tested the water quality during each season. The variations in water quality parameters relating to the different land use types of the sub-watersheds were analyzed using ANOVA. Results: Kebena watershed is mainly covered by 39.14% forest, 32.51% built-up area and 27.25% cultivated land. At sub-catchment level, Denkaka, (agriculture dominated) sub-catchment with 44.90 % cultivated land, Little Kebena, (forest dominated) sub-catchment, with 60.87% forest cover and Ginfle (urban dominated) sub-catchment with 90.44% built-up area were identified. The variations in water quality parameters relating to the different land use types of Kebena watershed revealed the significantly high seasonal relationship between the concentration of the water quality indicators during the dry season at (P<0.001, P<0.05). Furthermore, there is a strong positive relationship between the urban and forest dominated sub-catchments and water quality indicators during both the wet and dry seasons than agriculture dominated sub-catchment.Conclusion: Integrating watershed planning with land use planning, therefore, becomes one of the vital tools to address water quality problems in a holistic manner to further prioritize restoration and protection strategies for specific sub-catchments. Thus, in the urban dominated sub-catchment, relocating riverfront communities, providing a well-designed sewage system, applying appropriate storm water management schemes, are some of the important measures while providing wide river buffers with various vegetation cover are necessary to minimize pollutants influx to the river from the agriculture dominated sub-catchment. Furthermore, in the forested sub-catchment, applying preventive measures to retain and enhance connectivity of the existing natural green spaces through open space planning, development and management schemes is crucial.

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LAND USE TYPES AND SOIL CHARACTERISTICTS: A CASE STUDY IN HUONG VINH COMMUNE, HUONG TRA TOWN, THUA THIEN HUE PROVINCE

HUE UNIVERSITY JOURNAL OF SCIENCE EARTH SCIENCE AND ENVIRONMENT ◽

10.26459/hujos-ese.v126i4b.4121 ◽

2017 ◽

Vol 126 (4B) ◽

Author(s):

Trần Thanh Đức

Keyword(s):

Land Use ◽

Sweet Potato ◽

Soil Analysis ◽

Soil Characteristics ◽

Low Ph ◽

Clay Loam ◽

Total N ◽

Land Use Types ◽

Total P

This research carried out in Huong Vinh commune, Huong Tra town, Thua Thien Hue province aimed to identify types of land use and soil characteristics. Results showed that five crops are found in Huong Vinh commune including rice, peanut, sweet potato, cassava and vegetable. There are two major soil orders with four soil suborders classified by FAO in Huong Vinh commune including Fluvisols (Dystric Fluvisols, Gleyic Fluvisols and Cambic Fluvisols) and Arenosols (Haplic Arenosols). The results from soil analysis showed that three soil suborders including Dystric Fluvisols, Gleyic Fluvisols and Cambic Fluvisols belonging to Fluvisols were clay loam in texture, low pH, low in OC, total N, total P2O5 and total K2O. Meanwhile, the Haplic Arenosols was loamy sand in texture, poor capacity to hold OC, total N, total P2O5 and total K2O

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Bat Community Responses to Structural Habitat Complexity Resulting from Management Practices Within Different Land Use Types — A Case Study from North-Eastern Germany

Acta Chiropterologica ◽

10.3161/15081109acc2018.20.2.010 ◽

2019 ◽

Vol 20 (2) ◽

pp. 387 ◽

Cited By ~ 4

Author(s):

Nicole Starik ◽

Thomas Göttert ◽

Emanuel Heitlinger ◽

Ulrich Zeller

Keyword(s):

Land Use ◽

Habitat Complexity ◽

Management Practices ◽

Community Responses ◽

Eastern Germany ◽

Land Use Types ◽

North Eastern ◽

Structural Habitat

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THE IMPACT OF DIFFERENT URBAN LAND USE TYPES ON AIR POLLUTION IN THE MEGACITY OF SÃO PAULO

Revista Presença Geográfica ◽

10.36026/rpgeo.v7i1.5366 ◽

2020 ◽

Vol 7 (1) ◽

pp. 91

Author(s):

Júlio Barboza Chiquetto ◽

Maria Elisa Siqueira Silva ◽

Rita Yuri Ynoue ◽

Flávia Noronha Dutra Ribieiro ◽

Débora Souza Alvim ◽

...

Keyword(s):

Land Use ◽

Air Pollution ◽

Urban Land ◽

Sao Paulo ◽

Urban Land Use ◽

São Paulo ◽

Land Use Types ◽

The Impact

A poluição do ar é influenciada por fatores naturais e antropogênicos. Quatro pontos de monitoramento (veicular, comercial, residencial e background urbano (BGU))da poluição do ar em São Paulo foram avaliados durante 16 anos, revelando diferenças significativas devidoao uso do solo em todas as escalas temporais. Na escala diurna, as concentrações de poluentes primários são duas vezes mais altas nos pontos veicular e residencial do que no ponto BGU, onde a concentração de ozonio (O3) é 50% mais alta. Na escala sazonal, as concentrações de monóxido de carbono(CO) variaram em 80% devido ao uso do solo, e 55% pela sazonalidade.As variações sazonais ede uso do solo exercem impactos similares nas concentrações de O3 e monóxido de nitrogênio (NO). Para o material particulado grosso (MP10) e o dióxido de nitrogênio(NO2), as variações sazonais são mais intensas do que as por uso do solo. Na série temporal de 16 anos, o ponto BGU apresentou correlações mais fortes e significativas entre a média mensal de ondas longas (ROL) e o O3 (0,48) e o MP10 (0,37), comparadas ao ponto veicular (0,33 e 0,22, respectivamente). Estes resultados confirmam que o uso do solo urbano tem um papel significativo na concentração de poluentes em todas as escalas de análise, embora a sua influência se torne menos pronunciada em escalas maiores, conforme a qualidade do ar transita de um sistema antropogênico para um sistema natural. Isto poderá auxiliar decisões sobre políticas públicas em megacidades envolvendo a modificação do uso do solo.

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