Surface water quality and deforestation of the Purus river basin, Brazilian Amazon

Ríos‐Villamizar, Eduardo Antonio; Piedade, Maria Teresa Fernandez; Junk, Wolfgang J.; Waichman, Andréa Viviana

doi:10.1007/s40071-016-0150-1

Cited by 27 publications

(10 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…More so, the pH values were all within the range of 6.5 to 8.5, as recommended in the World Health Organization guidelines [41]. Similar trends were also reported in the Senqu-Orange River [42], Silva et al [43], Ros-Villamizar et al [44], and Machado et al [45] in streams of the Piracicaba River basin, Brazil. Phiri et al [46] also showed that such slightly lower pH values in effluents from beverage factories as in the current study are due to the nature of the raw materials such as enzymes, lactic acid, benzoic acid, and yeasts that are commonly used in such industries.…”

Section: Resultssupporting

confidence: 75%

See 1 more Smart Citation

Downstream Effects of Industrial Effluents Discharge on Some Physicochemical Parameters and Water Quality Index of River Rido, Kaduna State, Nigeria

Butu¹,

Emeribe

Muoka

et al. 2022

Trop. Aqua. Soil Pollut.

View full text Add to dashboard Cite

The effects of industrial effluent discharge on the water quality of River Rido in Kaduna South, Kaduna State, were examined. These include the Northern Noodles discharge point, the Kaduna Refinery discharge point, and points downstream of the River Rido. An interval of 100m between sampling points was established to achieve an even representation of sampling points. The physico-chemical parameters investigated include pH, free dissolved carbon dioxide, alkalinity, hardness, sodium, electrical conductivity, Turbidity, total suspended solids, total phosphate, nitrate, sulfate, and dissolved oxygen. Mean levels of turbidity Total suspended solids and total phosphate at effluent discharge points, as well as in most areas downstream of the study area, were generally above permissible limits for drinking water. Statistical differences were observed in the concentration levels of investigated parameters between the control point and effluent discharge points, as well as between the control point and areas downstream of the study area. However, concentration levels were observed to be similar between discharge points and areas downstream of the study area, an indication of contamination downstream by effluent discharge upstream. Notwithstanding, the water quality index of physico-chemical parameters at both effluent discharge points and areas downstream of River Rido shows that the quality of the river ranged from good to excellent at effluent discharge points and areas downstream of River Rido, respectively. This might be attributed to the effect of dilution from rainfall. It is therefore recommended that wastewater effluent from the refinery and northern noodles be properly treated before discharged into the study area.

show abstract

Section: Resultssupporting

confidence: 75%

“…The WQI model as adopted by [44] was utilised. The approach makes use of just nine parameters for the computation of the water quality index of a sample of water.…”

Section: Water Quality Index Computation Wqimentioning

confidence: 99%

Downstream Effects of Industrial Effluents Discharge on Some Physicochemical Parameters and Water Quality Index of River Rido, Kaduna State, Nigeria

Butu¹,

Emeribe

Muoka

et al. 2022

Trop. Aqua. Soil Pollut.

View full text Add to dashboard Cite

show abstract

“…River water pH can also be altered due to terrestrial inputs because most soils in the humid tropics are acidic (e.g., pH = 4.5−6.4; Grip et al 2005). This acidity has both biological and chemical causes: microbial processes (e.g., aerobic oxidation, methanogenesis, sulfate reduction, nitrification) enrich the soil pore water with H + and various forms of oxidized C and N (e.g., CO 2 , CH 4 , NO 3 − ) (Melling et al 2005;Ríos-Villamizar et al 2017), and weathering of parent material may also directly acidify adjacent aquatic systems by reacting with precipitation or moisture. For example, acid sulfate soil (ASS) is widely distributed in tropical regions and is stable under anoxic conditions.…”

Section: Loggingmentioning

confidence: 99%

The impact of tropical land-use change on downstream riverine and estuarine water properties and biogeochemical cycles: a review

2021

View full text Add to dashboard Cite

Tropical primary forests have been disappearing quickly to make use of the land for commercial purposes. Land-use change has an impact on downstream aquatic processes, but those impacts have mainly been studied in temperate climate regions. The present article reviews the impacts of various tropical land-use changes caused by human activities on downstream riverine and estuarine water properties and biogeochemical cycles, focusing especially on the behaviors of nitrogen (N) and phosphorus (P). Logging of tropical primary forests, subsequent establishment of pasture lands, and occasional wildfire or intentional burning have decreased terrestrial N fixation and increased the discharge of P combined with soils, which has lowered the N:P ratio of dissolved inorganic nutrients in the adjacent stream waters and downstream rivers. Agricultural fertilizers and aquacultural practices basically cause nutrient enrichment in downstream riverine and estuarine waters, changing the N:P ratio depending on the source. Finally, urbanization causes eutrophication in many tropical estuaries, where a halocline forms easily because of a warm temperature throughout the year and the water at the bottom of the estuary tends to become hypoxic or anoxic. Overall, the impact of land-use change on aquatic processes may be more serious in tropical regions than in temperate or cold climate regions because of (1) a higher biomass and nutrient stock in original tropical forests; (2) higher precipitation, more frequent episodic flooding, and warmer temperatures in tropical regions; and (3) certain practices that are rapidly expanding in tropical regions such as land-based aquaculture. Various land-use changes are causing downstream nutrient enrichment or disturbance of the nutrient balance at tropical land-sea interfaces, and the overall N:P ratios in the aquatic ecosystem seem to be declining. Nonetheless, if proper management is conducted and the discharge of nutrients and soils ceases, tropical aquatic systems may have the potential to recover faster than those in other climate regions because of their abundant precipitation and warm temperature. Long-term monitoring and more attention to elemental stoichiometry are important areas for future research.

show abstract

“…This study was conducted in the Piagaçu‐Purus Sustainable Development Reserve (State of Amazonas, Brazil), which is located south of the confluence of the Solimões and Purus rivers (Figure 1). Lake Ayapuá is situated on the floodplain of the lower Purus River, a whitewater river characterized by high turbidity (20–40 NTU), nearly neutral pH (6–7), high productivity, warm waters, and abundant surface vegetation (Junk et al, 2012; Ríos‐Villamizar et al, 2017). The lake is an oblong, shallow, turbid water body bordered by seasonally flooded lowland forest ( várzea ).…”

Section: Methodsmentioning

confidence: 99%

Air‐breathing ecology ofArapaimasp.: Conservation implications for an imperilled fish

Stokes

Castello

Petersen

et al. 2021

Aquatic Conservation

View full text Add to dashboard Cite

Arapaima (Arapaima sp.) are highly overexploited fish endemic to the Amazon basin. Because the fish are obligate air‐breathers, it is possible to use surface‐breathing events to count individuals visually for population censuses important for conservation, yet uncertainties remain about body size and environmental influences on air‐breathing intervals, and thus count accuracy. This study examined relationships between breathing intervals and environmental parameters (e.g. water temperature and transparency) and body size for radio‐tagged arapaima (n = 12) in an upland river‐floodplain (Lake Ayapuá, Amazonas, Brazil). Generalized additive mixed models were used to evaluate environmental, size, and behavioural correlates of breathing intervals. Temperature was the most influential predictor of air‐breathing intervals, followed by body size. The shortest breathing intervals were associated with consecutive ‘aggressive’ breaths while the longest breathing intervals had consecutive ‘calm’ breaths. Type of breath, size, and temperature predictors revealed that breathing intervals ranged from 4 to 46 min and were not significantly different among life stages ( x¯ = 15.9 min for sub‐adults and adults (>1 m); x¯ = 14.8 min for juveniles (<1 m)). Whereas the current population census method uses fish counts in 20‐min intervals, this study found that 15% of observed breaths, and two thirds of fish, took longer than 20 min to breathe. These findings were obtained in relatively cool‐water environments, so it is recommended that future population census methods consider water temperature (e.g. extend intervals used for counts in cooler waters), which may improve the accuracy of census counts and thus further enhance arapaima conservation efforts. This study demonstrated an effective method in which fundamental biological information is used to inform and improve population census methods for an imperilled fish in a region where traditional stock assessment is ineffective. Similar approaches for adaptive stock assessments could be applied to improve conservation of other air‐breathing fishes (e.g. lungfishes) globally.

show abstract

Surface water quality and deforestation of the Purus river basin, Brazilian Amazon

Cited by 27 publications

References 9 publications

Downstream Effects of Industrial Effluents Discharge on Some Physicochemical Parameters and Water Quality Index of River Rido, Kaduna State, Nigeria

Downstream Effects of Industrial Effluents Discharge on Some Physicochemical Parameters and Water Quality Index of River Rido, Kaduna State, Nigeria

The impact of tropical land-use change on downstream riverine and estuarine water properties and biogeochemical cycles: a review

Air‐breathing ecology ofArapaimasp.: Conservation implications for an imperilled fish

Contact Info

Product

Resources

About