Identifying riparian vegetation as indicator of stream water quality in the Gilgel Gibe catchment, southwestern Ethiopia

Abstract

Riparian land use has substantial effects on aquatic habitats and biological communities resulting in a dramatic loss of natural riparian vegetation and affecting the physicochemical properties of streams. The study investigates the relationships among indigenous riparian plants and water quality in the upper Gilgel Gibe catchment in southwestern Ethiopia. The floristic composition of the riparian vegetation and the water quality of streams were studied at selected sites, ranging from first‐ to third‐order streams. We quantified relationships between disturbance level and both physicochemical characters and traits of riparian plant species during two sampling periods (December 2013 and April 2014). Data were collected from a priori designated three land use types (forest, plantation, and agriculture) and ranked along nine streams. Ranks were based on surrounding land use characteristics and deforestation categories. We used analysis of variance and the Tukey's post‐hoc test to conduct pair‐wise comparisons among different land use types. Both species richness and diversity values of forest sites were significantly (p < 0.001) higher than agricultural sites. Whereas, stream water quality deterioration indicator gradient such as total suspended solid, water turbidity, and orthophosphate was significantly (p < 0.001) higher in agricultural sites than forest sites. We identified species such as Croton macrostachyus, Ficus sur, Maytenus arbutifolia, and Millettia ferruginea as indicator species of water quality (p < 0.05). Our study is the first assessment of the role of indigenous plant species as indicator of highland stream water quality in the tropical area. The study contributes to the ongoing discussion on the assessment and monitoring of stream ecosystems and for following stream restoration projects in tropical regions around the globe.

Vegetation and water of lowland spring-wells in Po Plain (Northern Italy): ecological features and management proposals

“…A multidisciplinary approach for wetlands characterization would be opportune also if difficult to realize for the elevated number of wetlands and of the parameters to consider. Chemical-physical and ecological parameters could be however reduced identifying good environmental indicators, one of which could be the vegetation itself, as suggested by other authors (Clayton and Edwards 2006;Serteser et al 2008;Giupponi et al 2013;Alemu et al 2017).…”

Impact of adjacent land use on the ecological condition of riparian habitats: The relation between condition and vegetation properties

“…Also, some common agricultural practices, linked to intensive production, remove partially or totally the riparian vegetation bordering the cultivated lands. The loss of vegetation cover has been associated with a reduction in ecological services and highly important functions associated with the native vegetation, such as temperature and water quality regulation (Marsh et al, 2005; Alemu et al, 2017b). For instance, a difference of up to 11ºC in the daily maximum stream temperatures in the summer has been shown between vegetated and non‐vegetated streams (Marsh et al, 2005).…”

“…Available information from different parts of the world (e.g., South Africa, Australia, Puerto Rico and Mexico) shows how land use influences riparian vegetation properties (Heartsill‐Scalley and Aide, 2003; Marsh et al, 2005; Meek et al, 2010; Méndez‐Toribio et al, 2014). Some other studies have individually evaluated the impact of cattle ranching activities or agriculture on the ecological condition of riparian habitats (Jansen and Robertson, 2001; Alemu et al, 2017b), and, to the best of our knowledge, only one recent study specifically addresses how urbanization affects the ecological condition of riparian zones in Mexico (Díaz‐Pascacio et al, 2018). To understand the specific responses of riparian condition and vegetation properties to adjacent land uses, approaches assessing the variation in riparian habitats at the catchment scale are necessary.…”

Study of Light Intensity in Riparian Zone of Teak Production Forest in KHDTK Cemoro Modang

“…Vegetasi tebing sungai dapat meredam kecepatan aliran air sungai dan memindahkan distribusi kecepatan ke tengah sungai (Maryono, 2015). Vegetasi asli di sempadan sungai dapat menjadi indikator kualitas air sungai dan mendeteksi dampak kegiatan antropogenik di sepanjang aliran sungai (Alemu et al, 2017). Efektivitas vegetasi dalam menangkap kontaminan (nitrogen dan fosfor) dipengaruhi oleh lebar sempadan dan jenis vegetasi (Junior et al, 2015).…”