The article discusses the development of a simplified and robust biomonitoring framework for assessing ecological health in ecosystems, particularly focusing on aquatic and linked terrestrial environments within the Upper Tana River (UTR) watershed in Kenya. The authors argue that the current frameworks, like the Biological Condition Gradient (BCG) developed by the US EPA, can be effectively adapted for use by the public to monitor ecological conditions and support sustainable management efforts.
Historically, biological indicators have evolved from early monitoring systems that utilized benthic macroinvertebrates to modern Indices of Biotic Integrity (IBIs) and multivariate approaches. The BCG, built upon empirical observations of biological responses to stressors, provides a heuristic model to express habitat condition changes. This study aims to implement the BCG by linking biological data from seven taxonomic groups (e.g., fish, macroinvertebrates, diatoms, herpetofauna, vegetation, macrofungi, and birds) to assess ecological conditions across varying disturbance gradients in the UTR watershed.
The research involved categorizing sampling sites into BCG tiers based on biological data, water, and soil quality metrics. Results indicated that ecological conditions deteriorated with increased disturbances, generally tracking from undisturbed headwater sites to severely degraded downstream areas impacted by agricultural practices and land use changes.
The findings imply that multiple indicator taxa across aquatic and terrestrial ecosystems can provide a more comprehensive assessment of environmental health, thus enhancing community engagement in monitoring efforts. The authors call for national bioassessment frameworks to improve ecological data collection and support river rehabilitation initiatives, critical for ensuring sustainable water resources and ecosystem integrity in future efforts.