Heavy metals in surface sediments of Lake Naivasha, Kenya: spatial distribution, source identification and ecological risk assessment

Heavy metals in surface sediments of Lake Naivasha, Kenya: spatial distribution, source identification and ecological risk assessment

Heavy metals retained in sediments pose a threat to aquatic ecosystem and society. Knowledge of the status and sustainability of lake sediment in areas undergoing rapid economic development is scarce, and yet it is required in order to achieve the United Nations Sustainable Development goals. We inv...

Full description

Saved in:
Bibliographic Details
Published in:SN applied sciences Vol. 2; no. 2; p. 279
Main Authors: Olando, Grace, Olaka, Lydia A., Okinda, Philip O., Abuom, Paul
Format: Journal Article
Language:English
Published: Cham Springer International Publishing 01-02-2020
Springer Nature B.V
Subjects:
2. Earth and Environmental Sciences (general)
Agricultural wastes
Anthropogenic factors
Applied and Technical Physics
Aquatic ecosystems
Biodiversity
Chemistry/Food Science
Chromium
Cobalt
Copper
Earth Sciences
Ecological risk assessment
Economic development
Engineering
Environment
Environmental risk
Farming
Fluorescence
Heavy metals
Horticulture
Iron
Laboratories
Lake sediments
Lakes
Lead
Manganese
Materials Science
Metal concentrations
Metals
Multivariate analysis
Particle size
Pollution
Pollution index
Pollution load
Research Article
Risk assessment
Sediment load
Sediment pollution
Sediments
Shorelines
Spatial distribution
Sustainability
Sustainable development
Toxicity
X-ray fluorescence
Zinc
Kenya
Lake Naivasha
GIS
Ecological risk
Pollution
SDGs
Aquatic ecosystem
Africa
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Heavy metals retained in sediments pose a threat to aquatic ecosystem and society. Knowledge of the status and sustainability of lake sediment in areas undergoing rapid economic development is scarce, and yet it is required in order to achieve the United Nations Sustainable Development goals. We investigated heavy metal concentration in Lake Naivasha sediments using enrichment factor, geoaccumulation index, pollution load index (PLI), risk index (RI) and multivariate statistics to determine metal accumulation, distribution and the lake’s pollution status. Sediments sampling followed a grid approach, and seven heavy metals: Co, Cr, Cu, Mn, Pb, Zn and Fe, were analyzed in total; concentrations were determined using portable X-ray fluorescence. The distribution maps were interpolated in a GIS platform, and the toxicity risk of sediments was determined. The concentrations of elements in the sediments are in the following decreasing order: Fe > Mn > Zn > Cu > Cr > Co > Pb. High concentration of heavy metals is found in the southern shoreline and east of the lake due to shoreline discharge and agricultural effluents drained into the lake and shoreline transgression. Pb and Zn are of anthropogenic origin, while Cu and Mn originate from both natural and anthropogenic sources and Fe and Co are from natural sources. In addition, the mean toxicity decreases in the order: Cu > Fe > Co > Pb > Zn > Mn > Cr. The PLI values were above one (> 1), indicating progressive deterioration of the sediment quality. Though the overall ecological risk of the lake is low to moderate (RI 36.73–60.51), hotspots of pollution should be marked for intervention. This assessment also helps to fill the knowledge gap required to formulate the right policies in implementing sustainable development goals in similar lakes.
ISSN:2523-3963
2523-3971
DOI:10.1007/s42452-020-2022-y