Development of a Macroinvertebrate - based Index of Biotic Integrity (M-IBI) for Colombo-Sri Jayawardhanapura Canal System (A new approach to assess stream/ wetland health)

Abstract

Macroinvertebrates have been identified as excellent indicators of stream/ wetland health as they respond rapidly to environmental changes and provide short to medium term pollution history records. Current study was aimed to develop a Macroinvertebrate-based Index of Biotic Integrity (M-IBI) which is a new approach to monitor stream/wetland health of Colombo-Sri Jayewardenepura canal system. Sixty eight macroinvertebrate samples were obtained using a D-framed kick net from ten stations namely Kotte, Nawala, OUSL, Kirimandala Mw., Wellawatta, Orugodawatta, St. Sebastian, Beira Lake, Buthgamuwa and Royal Park representing main branches of the system and marshes covering dissimilar environmental conditions of the canal system during the period of Nov. 2008 to June 2009 on monthly basis. Habitat characteristics and some water quality parameters also recorded. For the index development, those ten stations were grouped into two as 'Reference' and 'Degraded' based on their environmental conditions. Then ten candidate metrics were selected out of 41 for M-IBI development after evaluating their sensitivity and appropriateness. Validity of the index was tested with a new independent data set. Scores acquired were positively correlated with DO values (r = 0.578). That concluded the potential of using M-IBI developed for biological monitoring and improving biotic integrity of streams/ wetlands.

Political animals in the Modern World: An Investigation of the National Animal Symbol

“…However, absence of a specified, concrete interpretation also means the constructed image of the nation is fuzzy. As the embedded national identity is vague, the symbol can accommodate competing interpretations from groups with conflicting agendas (Perera, 2005). For instance, the British flag has been used to "connote imperial power, tradition and national pride" by the far-right groups; but it was also adopted by the antiauthoritarian mobs to convey "progressive modishness" in the 1960s (Edensor, 2016, 25-26).…”

Evaluation of the water and sediment quality of a lotic water-body in the western coastal region of Sri Lanka using Rapid Bioassessment Protocol II (RBP II) of benthic macroinvertebrates

“…Studies on the relationships between biotic indices and water quality parameters are not common in the inland waters of Sri Lanka. In a study conducted in the Colombo-Sri Jayewardenepura Canal System, 'Reference' and 'Degraded' sampling sites have been identified based on the environmental conditions and macroinvertebrates and a Macroinvertebrate-based Index of Biotic Integrity (M-IBI) has been developed to monitor stream/wetland health (Perera et al 2012). In this study, H', EPT, FBI and TR have been found to be significantly correlated with water quality parameters such as dissolved oxygen concentration, Cl -concentration, total dissolved solids and conductivity.…”

“…However, diversity indices of benthic macro invertebrate communities have been used in several studies in order to monitor the environmental conditions (Gamlath and Wijeyaratne 1997;Dahanayaka and Wijeyaratne 2006;Perera et al 2012;Idroos and Manage 2012;Madhushanka et al 2014). In addition, many studies have concentrated on assessment of physicochemical parameters in the aquatic systems of Sri Lanka in order to identify the source and sink areas of pollutants (Sangakkara and Wijeyaratne 2015;Wijeyaratne 2016).…”