River ecosystems of the Central Highland ecoregion: Spatial distribution of benthic flora and fauna in the Plateau rivers (tributaries of the Yamuna and Ganga) in Central India

Abstract

This study reveals the relationship of biotic assemblages to their environments in the Central Highland Ecoregion rivers (Ken, Paisuni and Tons). Such knowledge will enhance our predictive abilities in the ecological studies and resource management in the concerned region. Rivers of an ecoregion are expected to harbour similar flora, fauna, and communities. This hypothesis was examined by tracking the spatial variation in richness, density, and taxonomic composition of benthic diatom and macroinvertebrate assemblages in three Plateau rivers whose course lay within 3°N latitude. Taxonomic richness and density decreased with the reduction of substrate size from the headwaters to the lowlands. Cluster and ordination analyses indicate prevalence of intrabasin rather than interbasin gradients of abundance. In both assemblages, the most abundant taxon is rarely similar longitudinally or across the river sections in the ecoregion. Hence, proximate factors govern the assemblages rather than ecoregional properties (latitude, altitude). This, and the high richness of diatom flora, points to diverse assemblages from the headwater to the lowland section in each river and among the rivers of the ecoregion.

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“…El intervalo de los valores del índice de diversidad es similar a los de otros estudios con macroinvertebrados que se hicieron tanto en el Cupatitzio en los sitios pertenecientes a la cabecera del río (2.7-3.4, Pérez et al, 2006) como en otros ríos considerando todo el cauce (0.38-3.48, Barton & Metcalfe-Smith, 1992;Ginebreda et al, 2010). Algunos estudios han encontrado que, debido a los procesos de contaminación de la calidad del agua (descargas de aguas negras y fuentes difusas) y la degradación del hábitat (reducción del tamaño de substrato), la riqueza y diversidad disminuyen a manera de gradiente de donde inicia el río hacia su desembocadura y que organismos oportunistas aumentan su población (Ruaro et al, 2016;Nautiyal et al, 2017). Al analizar los resultados del presente estudio, la diversidad solo es mayor en tiempo de lluvias en los primeros sitios comparado con el resto.…”

The distributional pattern of benthic macroinvertebrates in a spring-fed foothill tributary of the Ganga River, western Himalaya, India

“…Community species distributions vary with water characteristics (Pereira & De Luca 2003;Silveira et al 2006). Benthic organisms are sensitive to the habitat characteristics and substratum (Buss et al 2004;Mishra & Nautiyal 2016), water temperature (Camargo & Voelz 1998;Mishra & Nautiyal 2011), pH (Sandin & Johnson 2004), electrical conductivity (Buss et al 2002), riparian vegetation (Silveira et al 2006), sedimentation (Smith & Lamp 2008), and land-use (Collier et al 2000;Kratzer et al 2006;Nautiyal et al 2017). Thus they can be used as indicators of the functional status of rivers (Jiang et al 2011;Mishra & Nautiyal 2013a).…”

Drivers of Benthic Macroinvertebrate Assemblages in Equatorial Alpine Rivers of the Rwenzoris (Uganda)

“…The macroinvertebrate families present in a community depend on the physical characteristics, disturbance levels, and biotic factors of the ecosystem. Global studies have further revealed that physicochemical variables (temperature and channel stability) and geographical variables (altitude and longitude) influence macroinvertebrate community patterns in both tropical and temperate aquatic systems [53][54][55][56][57][58]. These studies revealed that temperature influences macroinvertebrate diversity along an altitudinal gradient.…”