Temporal variations in water quality of farm dams: impacts of land use and water sources

Brainwood, Meredith A; Burgin, Shelley; Maheshwari, Basant

doi:10.1016/j.agwat.2004.03.006

Cited by 73 publications

(57 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, there is little agricultural activity in the Tyume catchment. In this case, nutrient loadings typically arise from non-point source run-off from flash storms, particularly in urban areas (Brainwood et al 2004). In summer and spring when there was less rainfall, and hence low flow, the effects of sewage discharge into the river were evident from the higher nutrient concentrations observed at Alice and Drayini sampling points.…”

Section: Resultsmentioning

confidence: 98%

“…A quick glance at the mean values for EC in Table 2a shows that the mean values become progressively bigger from Hala to Manqulweni (upstream to downstream), contrary to the most commonly held notion that pollute concentration becomes progressively lower as we go downstream due to the effect of dilution and self-purification capacity of the river (Osode and Okoh 2009). A combination of factors can be used to explain the observed trend and these include dispersed (non-point) pollution sources, the water's increased contact with soil with time and distance of flow and also the cumulative effect of ions, as more and more tributaries/rivulets discharge their loads into the main stream (Brainwood et al 2004). Sewage disposal and urban surface run-off in the downstream stretch of the river may also have contributed to the observed pattern.…”

Section: Resultsmentioning

confidence: 99%

“…Nitrate and nitrite compounds are very soluble in water and quite mobile in the environment (Blanchard and Lerch 2000). They have a high potential for entering surface water during rainfall events, as nitrates in applied fertilisers can dissolve in runoff that flows into streams (Brainwood et al 2004). Nitrates themselves are relatively non-toxic and normal individuals have low levels (0.5-2 %) of methemoglobin in their blood (EPA 2007).…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Characterisation of the physicochemical qualities of a typical rural-based river: ecological and public health implications

Sibanda

Chigor

Koba

et al. 2013

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

The physicochemical qualities of a typical rural-based river were assessed over a 12-month period from August 2010 to July 2011 spanning the spring, summer, autumn and winter seasons. Water samples were collected from six sampling sites along Tyume River and analysed for total nitrogen, orthophosphate, biochemical oxygen demand (BOD), temperature, pH, dissolved oxygen (DO), electrical conductivity (EC), total dissolved solids (TDS) and turbidity. BOD regimes did not differ significantly between seasons and between sampling points and ranged from 0.78 to 2.76 mg/L across seasons and sampling points, while temperature ranged significantly (P \ 0.05) between 6 and 28°C. Turbidity varied significantly (P \ 0.05) from 6 to 281 nephelometric turbidity units while TDS (range 24-209 ppm) and conductivity (range 47.6-408 mg/L) also varied significantly (P \ 0.05) across sampling points with a remarkable similarity in their trends. Orthophosphate concentrations varied from 0.06 to 2.72 mg/L across seasons and sampling points. Negative correlations were noted between temperature and the nutrients, DO and temperature (r = -0.56), and TDS and DO (r = -0.33). Positive correlations were noted between TDS and temperature (r = 0.41), EC and temperature (r = 0.15), and DO and pH (r = 0.55). All nutrients were positively correlated to each other. Most measured parameters were within prescribed safety guidelines. However, the general trend was that water quality tended to deteriorate as the river flows through settlements, moreso in rainy seasons.

show abstract

Section: Resultsmentioning

confidence: 98%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Characterisation of the physicochemical qualities of a typical rural-based river: ecological and public health implications

Sibanda

Chigor

Koba

et al. 2013

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…The water quality of Ds showed that it was controlled by hydrology and land use. According to Brainwood et al (2004) direct precipitation generally comprise less than one-tenth of total water input, while surface waters as runoff can comprise nearly all the water in the farm dam. Likewise, low NO 3 -N levels which were recorded in many Ds could be due to low NO 3 -N concentration recorded from adjacent F and PF land use type that provided runoff catchment to observed Ds.…”

Section: Water Quality Characteristicsmentioning

confidence: 99%

Robust optimal model for sustainable joint production of green tea and paddy rice in Japanese agricultural watersheds

Mabaya

Unami

Takeuchi

et al. 2017

IJISD

View full text Add to dashboard Cite

Abstract:In Japanese hilly agricultural watersheds, green tea is a profitable crop, whereas paddy rice cannot endure without subsidies. Environmentally, green tea plantations are the highest nitrate pollutant emitters to water bodies, whereas paddy fields are the most significant nitrogen sinks. This study investigates the effectiveness of diverting nitrate-contaminated drainage water from upland tea fields to the lowland paddy fields, in terms of reduction of downstream pollution and rice production cost, using the robust optimal model. The model optimally maximises diversions to reduce nitrate pollution to the adjacent rivers, and is environment risk averse to possible malfunctioning denitrification processes in the respective paddy fields. The application shows increased diversions to paddy fields during the rice growing season, thereby facilitating rice plants to have optimal access to substantial amounts of nitrogen nutrients and water. Thus, the robust optimal model has the potential to support sustainable joint production of the two crops.Keywords: robust optimisation; sustainable production; green tea; paddy rice; agricultural drainage water; nitrogen pollutants.Reference to this paper should be made as follows: Mabaya, G., Unami, K., Takeuchi, J., Fujihara, M. and Yoshioka, H. (2017) 'Robust optimal model for sustainable joint production of green tea and paddy rice in Japanese agricultural watersheds ', Int. J. Innovation and Sustainable Development, Vol. 11, No. 1, 70 G. Mabaya et al.Biographical notes: Goden Mabaya, MSc (Water Science and Engineering) 2012 UNESCO-IHE, Netherlands, is a PhD student in Water Resources Engineering at the Graduate School of Agriculture, Kyoto University, Japan. He has an extensive technical experience in planning, designing, construction and water management of multiuser irrigation and drainage systems in Africa. His research interests are robust optimisation of integrated agricultural watershed management with an emphasis on environmental sustainability, environmental water quality management, and post-modernisation of irrigation and drainage systems.Koichi Unami, PhD (Agriculture) 1998, Kyoto University, is an Associate Professor at Graduate School of Agriculture, Kyoto University, Japan. His research topics include theories and practices of water resources and environment management in rural areas, with specific emphasis on robustness in decision-making under uncertainty. For example, he determines operation rules for irrigation dams with irregular occurrence of recharge events in the framework of stochastic control. He is also an expert in field studies with different agro-ecological climates in Asia and Africa, such as Lake Biwa Basin of Japan and Volta Basin of West Africa.Junichiro Takeuchi, PhD (Agriculture) 2010, Kyoto University, is an Assistant Professor of Water Resources Engineering at Graduate School of Agriculture, Kyoto University, Japan. His main research interests include fluid flow and solute/energy transport through porous media and environmentally so...

show abstract

“…Using paired t-test, the results show significant seasonal variation (P=0.001, T=-9.506). Potassium concentrations increase in water bodies due to salts and nutrients leached to the water table during rainy season [36].…”

Section: Chemical Parametersmentioning

confidence: 99%

Assessment of Yatta Canal Water Quality for Irrigation, Machakos County, Kenya

Manohar¹,

Mang'oka²,

Ndunda³

et al. 2017

J Environ Anal Toxicol

View full text Add to dashboard Cite

Temporal variations in water quality of farm dams: impacts of land use and water sources

Cited by 73 publications

References 29 publications

Characterisation of the physicochemical qualities of a typical rural-based river: ecological and public health implications

Characterisation of the physicochemical qualities of a typical rural-based river: ecological and public health implications

Robust optimal model for sustainable joint production of green tea and paddy rice in Japanese agricultural watersheds

Assessment of Yatta Canal Water Quality for Irrigation, Machakos County, Kenya

Contact Info

Product

Resources

About