Assessment of Urban Sprawl, Land Use and Land Cover Changes in Voi Town, Kenya Using Remote Sensing and Landscape Metrics

Peer reviewe

Habitat suitability modelling to improve conservation status of two critically endangered endemic Afromontane forest bird species in Taita Hills, Kenya

Tropical montane forests are known to support many endemic species with restricted geographic ranges. Many of these species are however, faced with numerous threats, most notably from habitat loss and degradation, invasive alien species, and climate change. Examples include Taita Apalis and Taita Thrush. Taita Apalis (Apalis fuscigularis) and Taita Thrush (Turdus helleri) are species of birds listed as Critically Endangered by the Government of Kenya and the International Union for Conservation of Nature (IUCN). They are endemic to Taita Hills' cloud forests in southeastern Kenya and protected under Wildlife Conservation and Management Act. As they face high risk of extinction, exploring their habitat suitability is imperative for their protection. To determine the current spatial distribution and the key ecogeographical explanatory factors and conditions affecting species distribution and indirect effects on species survival and reproduction, we employed Maximum Entropy (MaxEnt) modelling. This study was conducted in Ngangao and Vuria forests in June and July 2019 and 2020. Ngangao forest is gazetted as forest reserve and managed by the Kenya Forest Service whereas Vuria is nongazetted and thus remains without official protection status. Ecogeographical explanatory variables; climatic, remote sensing-, LIDAR-, topography-and landscape-based variables were used in modelling and separate models were produced. 23 occurrence records of Taita Apalis and 30 of Taita Thrush from Ngangao and 21 of Taita Apalis from Vuria forests were used in the modelling. According to the models, less than 7% of the total area of Ngangao and Vuria forests was predicted as suitable habitat for Taita Apalis and Taita Thrush. This shows that these two species are more vulnerable to extinction from demographic stochasticity. Consequently, managing their habitats is critical for their long-term persistence. LIDAR-based canopy height range and elevation greatly influenced Taita Apalis distribution in Ngangao forest, with areas of high elevation (1620-1750 m a.s.l.) and having open middle-storey preferred. Elevation, slope and topographic wetness index (twi) were the major determinants of Taita Thrush distribution in Ngangao, where gentle sloping areas with moderately dry surfaces within high elevation (1620-1730 m a.s.l.) were favoured. Mean annual temperature, Euclidean distance to the forest edge, slope and land cover type greatly influenced the distribution of Taita Apalis in Vuria, with gentle sloping areas within forest interior made up of indigenous vegetation preferred. This study proposes reforesting open and degraded sites next to areas predicted as highly suitable for the two species; establishment of agroforestry belts based on indigenous trees on the boundaries of the two forests to reduce grazing and firewood collection pressure and enhance resilience to the edge effects; and enhancing forest protection through Participatory Forest Management.Peer reviewe

Species identity and behavior of cave-dwelling tree hyraxes of the Kenyan coast

We surveyed tree hyrax populations living in forests, limestone rocky formations, and caves in coastal Kenya to identify the species and estimate the threat-level populations are in. Tree hyrax vocalizations were recorded in three different habitats with passive acoustic monitoring (PAM) for a total of 84 h in January and February 2022. We also observed tree hyrax behavior with thermal imaging camera and photographed individuals. Tree hyraxes in coastal Kenya are vocally active throughout the night, with most calls emitted between 23.00 and 04.00. We identified four different calls: snort, hac, hac ping-pong, and wheeze. Their calling range is between 220 and 15,000 Hz. Calls of tree hyraxes from the coast of Kenya were compared with calls stored by the Oxford Brookes University's Nocturnal Primate Research Group and identified as eastern tree hyrax, previously recorded from Tanzania. Here, we present what are, to our knowledge, the first photographs of live D. validus from Kenya. These tree hyraxes live in social groups. Due to strong pressure from humans, conservation measures are necessary to prevent the extinction of these isolated D. validus populations in Kenya.Peer reviewe

Behind the fog : Forest degradation despite logging bans in an East African cloud forest

Habitat destruction and deterioration are amongst the main drivers of biodiversity loss. Increasing demand for agricultural products, timber and charcoal has caused the rapid destruction of natural forests, especially in the tropics. The Taita Hills in southern Kenya are part of the Eastern Afromontane Biodiversity Hotspot and represent a highly diverse cloud forest ecosystem. However, the cloud forest suffers extremely from wood and timber exploitation and transformation into exotic tree plantations and agricultural fields. Existing conservation regulations and moratoriums aim to prevent further forest destruction. In this study, we analyzed land cover change and shifts in landscape configuration for a fraction of the Taita Hills, based on satellite imageries for the years 2003, 2011 and 2018. We found that the coverage of natural cloud forest further decreased between 2003 and 2018, despite the effort to conserve the remaining cloud forest patches and to reforest degraded areas by various conservation and management initiatives. In parallel, the proportion of exotic tree plantations and bushland strongly increased. Moreover, mean natural forest patch size decreased and the degree of interspersion with other land cover types increased notably. Logging bans for indigenous trees seem to have resulted in local opposition to the planting of indigenous trees and thereby hindered the recovering of the cloud forest. We suggest to enhance local awareness on the ecological value of the natural forest by community-based Conservation Forest Associations and to encourage the planting of indigenous tree species in farmer-owned woodlots. Besides, bottom-up management systems that allow for local participation in decision-making and benefit-sharing related to forest resources would be a way forward to achieve the sustainable use and conservation of the last remaining natural forest patches in the Taita Hills. (C) 2020 The Authors. Published by Elsevier B.V.Peer reviewe

Habitat preferences, estimated abundance and behavior of tree hyrax (Dendrohyrax sp.) in fragmented montane forests of Taita Hills, Kenya

We studied a previously almost unknown nocturnal mammal, an apparently undescribed species of tree hyrax (Dendrohyrax sp.) in the moist montane forests of Taita Hills, Kenya. We used thermal imaging to locate tree hyraxes, observe their behavior, and to identify woody plants most frequently visited by the selective browsers. We also documented acoustic behavior in forest fragments of different sizes. Data on calling type and frequency were analyzed together with lidar data to estimate population densities and to identify forest stand characteristics associated with large populations. Viable populations were found only in the largest forest fragments (> 90 ha), where tree hyraxes preferred most pristine forest stands with high, multilayered canopies. The estimated population sizes in smaller forest fragments were very limited, and hyraxes were heard to call only during late night and early morning hours, presumably in order to avoid detection. While we frequently recorded tree hyrax songs in the largest forest fragments, we almost never heard songs in the small ones. All remaining subpopulations of the Taita tree hyrax are under threat of human disturbance and further habitat deterioration. Conservation efforts should include protection of all remaining habitat patches, but also reforestation of former habitat is urgently needed.Peer reviewe

Cost-benefit analysis of sustainable land and water management practices in selected highland water catchments of Kenya

Sustainable land management (SLM) strives to maintain and improve the agricultural production capacity of land. To achieve the goals of SLM, communities use various types of agronomic, vegetative, and structural practices. Despite the benefits of SLM practices, some farmers are reluctant to adopt them. An economic cost-benefit analysis of SLM practices is an important approach to demonstrate the benefits of appropriate SLM practices. This study was conducted to determine the effect of adopting of SLM practices, and also the costs and benefits associated with adopting SLM practices in Kinale-Kikuyu, Cherangani, and Wundanyi water catchments in Kenya. A multistage, probability proportional to size sampling method was used to select 388 households for a cross-sectional survey in the year 2015. The study used the World Overview of Conservation Agriculture Technologies survey tools in a mixed-methods research technique. Profitability analysis, return on investment, and sensitivity analyses were conducted. Terraces, infiltration ditches, and trash lines were popular practices adopted by farmers. The cost of establishing terraces on a hectare of land was US$445. The most expensive vegetative SLM practice, woodlot, costed US$ 534 per hectare to establish. Average yields increased by 49.8% in Kinale-Kikuyu, 60.6% in Cherangani, and 107.5% in Wundanyi due to adoption of SLM practices. Yield increases of 8.7% in fodder maize and 108% in tomatoes and potatoes were observed. The percentage increase in mean annual gross margins due to adopting SLM practices was highest in Wundanyi at 242.09%. Cost-benefit analysis showed that Kinale-Kikuyu had the highest Net Present Value of US$ 4083.73 due to adopting SLM. Positive Net Present Values were an indicator of the benefits of SLM in all the catchments. Benefits accruing from the adoption of SLM practices by the farmers exceeded the costs of establishing the SLM structures in the long run. It is recommended that a pilot Payment for Ecosystem Services (PES) project be established on hilly catchments and for linkages to be made between markets for produce and farmers willing to adopt SLM practices as an incentive to adopt them

Allometric models for estimating leaf biomass of sisal in a semi-arid environment in Kenya

Publisher Copyright: © 2021 The AuthorsBiomass is a key variable for crop monitoring and for assessing carbon stocks and bioenergy potential. This study aimed to develop an allometric model for predicting the dry leaf biomass of sisal, an agave plant with crassulacean acid metabolism grown for fibre production in the tropics and subtropics and whose biomass can be utilised as a feedstock to produce biogas through anaerobic digestion. The allometric model was used to estimate leaf biomass and productivity across different stand ages in a sisal plantation in semi-arid region in south-east Kenya (annual rainfall 611 mm and temperature 24.9 °C). Based on a sample of 38 leaves, the best predictor for biomass was leaf maximum width and plant height used as a combined variable in a log-log regression model (cross-validated R2 = 0.96 and root-mean-square error = 7.69 g). The mean productivity in nine 26- to 36-month-old plots was 11.1 Mg ha−1 yr−1, which could potentially yield approximately 3000 m3 CH4 ha−1 yr−1. The leaf biomass in 55 field plots (400 m2 in area) ranged from 2.7 to 42.7 Mg ha−1, with mean at 13.5 Mg ha−1, which equals to 6.3 Mg C ha−1. The yielded allometric equations can be utilised for predicting the leaf biomass of sisal in similar agro-ecological zones. The estimates on plantation biomass can be used in assessing the role of sisal plantations as a regional carbon storage. In addition, the results provide reference on the productivity of agave and crassulacean acid metabolism in semi-arid regions of East Africa, where such reports are few.Peer reviewe

Master of Science in Climate-Smart Agriculture Curriculum

Food production faces interlinked challenges with increasing uncertainties from the increasing impacts of climate change and variability. The underlying philosophy of CSA is the development and promotion of an integrative approach that results in landscape management for productive croplands, livestock, forests, and fisheries. It aims for improved food and nutrition security and equitable livelihoods. The program seeks to support the achievement of three outcomes i.e. increased productivity (producing more food to improve food, nutrition, and income security and livelihood of the world’s resource-poor farmers in rural areas); enhanced resilience (contributing to training for reduced vulnerability to drought, pests, disease, and other shocks); reduced emissions (reducing emissions from production systems to protect the environment while increasing productivity); and improved capacity to adapt (increasing productivity in the face of extreme climatic weather patterns). The program anchors on existing knowledge, technologies, and principles of sustainable agriculture. The need to increase carbon sinks and reduce GHGs emissions is a priority consideration, especially during training for a sustainable agro-ecosystem. Its design explicitly focuses on addressing productivity and climate change mitigation and adaptation with consideration of the interactions and tradeoffs existing between them. Finally, the CSA program aims to support funding opportunities for innovation and technology development for extension through research investment

Bachelor of Science in Rangeland Ecosystem Management Curriculum

The School of Agriculture, Earth and Environmental Sciences strongly believes in supporting advances in various aspects of rangeland science and community development practices in the rangeland ecosystem. There is increasing need to have well trained personnel with expertise in sustainable rangeland management, to provide leadership and stewardship for a sustainable framework for managing rangelands. This paradigm underlies the philosophy of linking the programme delivery with hands-on training, support to applied research and policy support ability to effectively contribute to sustainable rangeland ecosystem development and management. Universities have a key role in providing technical support in theory and practice by being proactive in training, research and innovation for sustainable rangeland resource management. This degree programme will contribute to the goal of improving the rangeland ecosystem health, while supporting sustainable livelihood options of communities and biodiversity in these ecosystems

Master of Science in Rangeland Ecosystem Management Curriculum

The combination of inadequate understanding of the dynamics in rangeland ecosystems and local livelihood systems are to blame for the inappropriate policy actions, unabated rangeland degradation trends, impoverishment of communities living in the rangelands, and their increased vulnerability to various shocks including climate change. The root cause of these problems is mainly linked to lack of inadequate skilled human resources, trained in rangeland ecosystem management at the postgraduate level, to tackle the complex biodiversity interactions in the rangeland ecosystems. The philosophy of this degree programme is, therefore, anchored in the paradigm that rangelands are socio-ecological systems with complex biophysical, socio-cultural and economic interactions, which call for specialized managers and decision makers. This programme therefore, aims to produce a critical mass of rangeland ecosystem management experts equipped with requisite skills, technologies and innovations to further research, apply appropriate practices and influence policies in favour of resilient rangeland ecosystems and livelihoods. Trained skilled manpower is expected to act as a catalyst for enhancing the productivity and sustainability of rangeland ecosystems and livelihoods through practice, policies and research