Abstract Background: Peasant agroecosystems in Kenya are considered to be a continuum of integrated traditional farming systems and natural ecosystem conservancy programs. Hyphaene compressa (doum palm) exists in arid and semi-arid lands (ASAL) of Kenya. While research in these areas is focusing on new plants to be brought to the areas, there is no focus on doum palm, which is already adapted to these areas. Scanty ethnobotanical knowledge exists in the form of unpublished material. The stud...
Abstract/Overview Over 6% of agricultural land is affected by salinity. It is becoming obligatory to use saline soils, so growing salt-tolerant plants is a priority. To gain an understanding of the genetic basis of upland cotton tolerance to salinity at seedling stage, an intra-specific cross was developed from CCRI35, tolerant to salinity, as female with Nan Dan (NH), sensitive to salinity, as the male. A genetic map of 5178 SNP markers was developed from 277 F2:3 populations. The map sp...
Abstract Integrated soil fertility management and soil water conservation practices are possible solutions to persistent soil quality decline and low availability of soil moisture which are affecting agricultural productivity in the dry lands of Tharaka-Nithi County. Nonetheless, the rate of uptake of these technologies and practices by smallholder farmers has stagnated over the years despite recommendations for their use. Lack of effective communication between the extension agents and rese...
Abstract Degraded landscapes and soil water stress are long-standing problems to smallholder agriculture in the drylands. Despite the important roles of soil and water conservation in restoring degraded landscapes and improving agricultural productivity, the technologies are yet to be adopted to their fullest extent. This can be attributed to gender-linked disparities in agricultural technology utilization. This study, therefore, sought to evaluate gender-specific choice and use-intensity de...
Abstract Majority of the Kenyan population resides in rural areas and are characterised by high levels of poverty due to low income and food insecurity. Poultry production and in particular indigenous chicken has been recognised as an avenue to improve livelihoods among rural households through provision of income. Besides, the enterprise contributes to socioeconomic and nutritional requirements of rural and peri-urban populations. Despite this potential, chicken production continues to enco...
Abstract Mango (Mangifera indicia L.) is one of the most suitable fruit crops in arid and semi-arid areas of Kenya. Its production in Machakos County has generally been fluctuating over the past few years, such that there is no consensus whether the production is increasing or decreasing. In addition, there is a paucity of knowledge about the quantity of mangoes supplied by small-scale farmers. Upon harvest, the mango fruit is highly perishable, therefore farmers have taken up farm-level val...
Abstract Named after Hermann L. F. von Helmholtz (1821-1894), Helmholtz equation has obtained application in many elds: investigation of acaustic phenomena in aeronautics, electromagnetic application, migration in 3-D geophysical application, among many other areas. As shown in [2], Helmholtz equation is used in weather prediction at the Met O ce in UK. Ine ciency, that is the bottleneck in Numerical Weather Prediction, arise partly from solving of the Helmholtz equation. This study investig...
Abstract/Overview Cotton is a moderately salt-tolerant crop, but its salt tolerance threshold is not more than 7.7 ds•m−1. The seedling stage of cotton is the highly sensitive to salinity and the effects can be quantified by measuring morphological and physiological traits. The purpose of this study was to identify QTLs related with salinity tolerance at seedling stage. Meanwhile where they were localized in the genome, investigate the relationships between the traits at seedling stag...
Abstract/Overview CO2 fluxes were measured continuously for twelve months (2003) using eddy covariance technique at canopy layer in a dominant subtropical forest in South China. Our results showed that daytime maximum CO2 fluxes of the whole ecosystem varied from −15 to −20 µmol m−2 s −1 5 . The peaks of CO2 fluxes appeared earlier than the peaks of solar radiation. Contribution of CO2 fluxes in a subtropical forest in the dry season was 53% of the annual total from the whole for...
Abstract/Overview Strong seasonal variability in African carbon source/sink relationship is considered the continent’s most significant contribution to the global carbon cycle. Alternating dry and wet periods dictate ecosystem carbon exchange and productivity of tropical African savannah. We examined the seasonal and daily trends in ecosystem CO2 exchange in the herbaceous layer of a humid Kenyan savannah devoid of grazing. Microclimate, soil moisture, soil and tissue nitrogen, abovegro...
Abstract/Overview Functional convergence in water use of trees across species from diverse geographic locations was examined using data on tree water use parameters, with the intention of gaining an understanding on the capacity for water transport for trees with varying structural and functional traits. Wood density (ρw), which is reported to have a negative exponential relation with sap flow density (SFD), showed a bell-shaped curve when the daily SFD data from 101 tree species belongi...
Abstract/Overview Experiments were conducted between 2003 and 2008 to examine how N additions influence soil organic C (SOC) and its fractions in forests at different succession stages in the subtropical China. The succession stages included pine forest, pine and broadleaf mixed forest, and old‐growth monsoon evergreen broadleaf forest. Three levels of N (NH4NO3)‐addition treatments comprising control, low‐N (50 kg N ha–1 y–1), and medium‐N (100 kg N ha–1 y–1) were est...
Abstract/Overview Data collected on a free ranging group of Tana River mangabeys (Cercocebus galeritus) indicates that this endangered primate species, which has previously been regarded as a seed predator, plays an important role in seed dispersal and do contribute to the regeneration of a highly fragmented gallery forest. We observed fruit handling behavior and the post-dispersal fate of seeds ingested by the mangabeys. The two main fruit handling behaviors observed, fruit swallowing an...
Abstract/Overview Agricultural intensification is a leading cause of global biodiversity loss, which can reduce the provisioning of ecosystem services in managed ecosystems. Organic farming and plant diversification are farm management schemes that may mitigate potential ecological harm by increasing species richness and boosting related ecosystem services to agroecosystems. What remains unclear is the extent to which farm management schemes affect biodiversity components other than speci...
Abstract Four proximal soil sensors were tested at four smallholder farms in Embu County, Kenya: a portable X-ray fluorescence sensor (PXRF), a mobile phone application for soil color determination by photography, a dual-depth electromagnetic induction (EMI) sensor, and a LED-based soil optical reflectance sensor. Measurements were made at 32–43 locations at each site. Topsoil samples were analyzed for plant-available nutrients (N, P, K, Mg, Ca, S, B, Mn, Zn, Cu, and Fe), pH, total nitroge...