Browsing by Author "Kutuny, G.K"

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ASSESSMENT OF BENTHIC MACROINVERTEBRATES AS BIOINDICATORS OF WATER QUALITY IN RIVER NAKA, CHUKA, THARAKA-NITHI, KENYA
(chuka university, 2022) Chuka, University; Chamia, L.K; Kutuny, G.K
Freshwater ecosystems worldwide have been progressively deteriorating leading to a decrease in aquatic biodiversity. Conventionally, evaluation of water quality uses single physical-chemical parameters which may be insufficient to fully assess the quality of freshwaters. This study used bio-indicators to assess water quality of River Naka in Tharaka-Nithi County, Kenya. Fluvial ecosystems support rich and diverse assemblages, making them vulnerable to possible alterations in the habitat. The study assessed the diversity and abundance of benthic macroinvertebrate communities and their use as bioindicators of water quality. Grab sampling was used to collect water samples, a kick sampler and D-frame aquatic net was used to collect 121 benthic macroinvertebrates from three selected sites and determined using EPT Index (Ephemeroptera, Plecoptera and Trichoptera group). The data obtained was used to determine the index of the sampling sites. Physico-chemical factors were analyzed in-situ (temperature, turbidity and pH) and in the laboratory(nitrates and phosphates). The highest EPT index values (28) at the upstream corresponded to good water quality, while the slightly low values (21) at the midstream indicated moderate water quality and the lowest values (15) recorded at the downstream showed fair water quality. The downstream water quality parameters exceeded World Health Organization limits, posing a health risk to water consumers. Continuous bio-assessment of rivers based on EPT biotic indicators should be conducted on a regular basis to establish a long-term profile of water quality state and ecological integrity of rivers.
INFLUENCE OF VARIATION IN BIOPHYSICAL FACTORS ON TREE SPECIES STRUCTURE AND COMPOSITION IN KAPSERET FOREST, UASIN GISHU COUNTY, KENYA
(chuka university, 2022) Kutuny, G.K; Njeru, J.R; Mutuma, E
Forests are important for survival and development of human and other fauna. However, they are under degradation due to changes in biophysical factors which affects tree species structure and composition. Understanding these variations and their influence on tree species structure and composition guides conservation of forest. This study aimed at assessing the influence of variation in biophysical factors on tree species structure and composition. Ecological survey was used whereby, tree species and soil samples were studied from 12 sample plots identified through stratified sampling techniques within Kapseret forest. Tree species were enumerated and recorded by species name and Diameter at Breast Height (DBH), those with ≥3m height and DBH > 9.5 cm were classified as trees, while those with ≤3m height and less than DBH ≤ 9.5cm were recorded as saplings. Tree species attributes assessed included: tree DBH and diversity, while biophysical variables measured were: soil organic carbon (SOC), soil texture, phosphorous and potassium. A total of 148 tree species were identified with 62.16% being saplings while 35.14% were mature trees. The CCA results indicated positive correlation between tree species diversity with variation in biophysical factors, the presence of gaps with high P levels were associated with majority of the saplings, however, the DBH class distribution did not indicate an inverse J-shape portraying high degradation. The tree species-biophysical factors should therefore be utilized with other environmental factors such as topography,light intensity,temperature and wind when planning and choosing species for rehabilitation and restoration of degraded landscapes.