Photosynthesis and Water Relations of Two Savanna Grasses as Influenced by Shade and Water Stress

Net CO2 assimilation and plant water relations of the African savanna grasses Panicum maximum Jacq. and Tliemeda triandra Porrsk. were measured under controlled conditions. We hypothesised that 1; triandra would be better adapted to higher light and temperature conditions and could withstand greater moisture stress than could P. maximum, as T. tria11dra is commonly found in open areas, whereas P. maximum dominates in the shade of trees. Plants of both species were transplanted into a common soil in large pots and placed under shade (approximately 150 µrnoVm1/s photon flux density (PFD)) or high light (approximately 1200 µmoVm1/s PFD) conditions, with either no imposed drought or periodic drought. Both species responded similarly to stressors of shade and drought. Few significant interactions between species ·and light regime or species and water regime were found, Species responded similarly if grown together or in a monoculture. Therefore, this study did not indicate competitive reactions or ecophysiological reasons why P. maximum should dominate shady habitats, and T. triandra should dominate open grasslands

An Ecosystem Modelling Approach to Rehabilitating Semi-Desert Rangelands of North Horr, Kenya

Decreased rainfall, recurrent droughts and increased anthropogenic activities have led to a dramatic increase in wind erosion on pastoral lands of North Horr resulting in the reactivation of the once-stable sand dunes. This has degraded the vegetation and impoverished the local community. Mobile sand has a severe impact on dry season grazing areas (Omar & Abdal, 1994) and, therefore, affects pastoral livestock production. In North Horr, Suaeda monoica is important in camel production and for stabilising sand dunes but it has been over-utilized over the years. The objective of this study was to use ecosystem modelling approaches to examine the issue of land rehabilitation in North Horr taking cognisance of emerging perspectives on interactions among climate, plants and herbivory in such rangelands

Enhancement of Grassland Production Through Integration of Forage Legumes in Semi-Arid Rangelands of Kenya

Livestock production in semi-arid rangelands of Kenya is limited by the seasonal quantity and quality of fodder. Kirkman & Carvalho (2003) stated that these inter- and intra-seasonal quality and quantity fluctuations result in nutrient deficits that severely limit livestock production potential. The objective of this experiment was to study the effect of three forage legumes on the production of natural pastures in semi-arid rangelands of Kenya

Warburgia ugandensis and Polyscias fulva seedlings

Growth characteristics of two tropical forest specie

Livestock versus Wildlife Ranching in Kenyan Rangelands: A Case Study of Laikipia District Ranches

Past research has shown that livestock ranching per se has failed to sustain economic development in Laikipia district. Exploratory study results of livestock-wildlife mixed ranching in the district over the last two years are discussed. The results reveal a web of interactive factors involving land tenur, livestock development, disease control, marketing and environmental conservation that need to be considered if the newly emerging mixed -livestock ranching system can be feasible. Failure to consider this web of interactions has contributed to constraints in the efforts to develop a viable livestock –wildlife mixed ranching system. Attempts that could lead to amelioration of these constraints are suggested in this paper. The Kenya Veterinarian Vol. 27 2004: pp. 24-3

Phenology of Avicennia marina (Forsk.) Vierh. in a disjunctly zoned mangrove stand in Kenya

info:eu-repo/semantics/publishe

Vegetative phenology of Rhizophora mucronata Lamk. Avicennia marina (Forsk.) Vierh. and Sonneratia alba Sm. in natural and reforested stands at Gazi Bay, Kenya

info:eu-repo/semantics/nonPublishe

Vegetative phenology of Rhizophora mucronata Lamk. Avicennia marina (Forsk.) Vierh. and Sonneratia alba Sm. in natural and reforested stands at Gazi Bay, Kenya

info:eu-repo/semantics/nonPublishe