Identifying and classifying macroinvertebrate indicator signature traits and ecological preferences along urban pollution gradient in the Niger Delta. (15th July 2021)

• Record Type: Journal Article
• Authors: Edegbene, Augustine O.; Odume, Oghenekaro N.; Arimoro, Francis O.; Keke, Unique N.
• Is Part Of: Environmental pollution. Volume 281(2021)
• Publication Date: 2021-07-15
• Subjects: Urban pollution -- Pollution impact categories -- Signature traits -- RLQ and Fourth-corner analyses; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2021.117076
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Urbanisation of riverine landscape is an increasing threat to the functionality of river ecosystems. In this study, we identify and classify macroinvertebrates indicator signature traits and ecological preferences.We hypothesised that urban pollution would differentially influence the distribution of macroinvertebrate traits and ecological preferences along a gradient of water quality deterioration. Hence, we identified and classified potential biological indicators traits and ecological preferences that were deemed tolerant of or sensitive to urban pollution gradient in the Niger Delta region of Nigeria. Physico-chemical variables (water temperature, depth, flow velocity, dissolved oxygen, biochemical oxygen demand, electrical conductivity (EC), nitrate, phosphate), and macroinvertebrates were collected from 2008 to 2012 seasonally during the wet and dry seasons once in a month in 11 stations in eight river systems. The results based on RLQ, fourth-corner and Kruskal-Wallis analyses indicate that traits/ecological preferences such as tegumental/cutaneous respiration, cased/tubed body armouring, a preference for silty water, bivoltinism, burrowing and a high tolerance for oxygen depletion, were statistically significantly associated with the heavily impacted stations. These traits were positively correlated with physico-chemical variables such as EC, nitrate and phosphate indicative of urban pollution. On the other hand, traits/ecological preferences such as permanent attachment, crawling, swimming, univoltinism and a moderate sensitivity to oxygen depletion were associated with the least impacted stations and were negatively correlated with physico-chemical variables indicative of urban pollution. Overall, the observed differential responses of traits and ecological preferences to urban pollution along a gradient of water quality impairment suggest that traits and ecological preferences can serve as useful biological indicators and thus supports the growing evidence of the utility of the trait-based approach. Graphical abstract: Image 1 Highlights: River sites were physico-chemically classified into three impact categories. Traits and ecological preferences were either sensitive to or tolerant of urban pollution. Crawling, swimming and univoltinism were sensitive to urban pollution. Traits and ecological preferences responded differentially to urban pollution. Abstract : The study identified univoltinism, permanent attachment, crawling, swimming, moderate sensitivity to oxygen depletion as traits/ecological preferences sensitive to urban pollution. Traits/ecological preferences including tegumental/cutaneous respiration, cased/tubed body armouring, a preference for silty waters, bivoltinism, burrowing and a preference for depleted dissolved oxygen were identified as tolerant of urban pollution. These traits/ecological preferences can thus serve as indicators for biomonitoring of urban river pollution.