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Avian and Habitat Diversity in the Semi-Arid Lands of Baringo South, Kenya

Open Journal of Ecology 2020年第8期10卷 518-536页

作者： George Morara Ogendi Rhoda N. Ondieki Department of Environmental Science Egerton University Egerton Kenya dryland research training & ecotourism centre Chemeron Egerton Kenya

Semi-arid wooded-shrublands are important and critical habitats that provide breeding and feeding grounds for a variety of bird species, some of which are endangered, vulnerable or threatened with extinction. Habitat type and size influence abundance and diversity of birds globally and particularly in developing countries that are characterized by rapid human population growth and haphazard urban, agricultural and industrial development. The objective of this study was to assess avian and habitat diversity at Chemeron, a semi-arid land in the northern rangelands of Kenya. The study was guided by four questions: What kind of Habitat types are present at Chemeron study area? What kind of birds are found at Chemeron area? What is the conservation status of birds found at Chemeron area? What are the functional feeding guilds of birds that are found in the study area? How does the habitat type influence bird species abundance and diversity at Chemeron? Four 2-km long transects radiating from a central point within the study area were selected for a ground survey of birds that was conducted on foot. The surveys were conducted between 06:30 and 09:30 and 16:00 and 18:00 from October 2019 to April 2020. Bird species were observed and identified to the species level using high-resolution binoculars, field guidebooks and available taxonomic keys. Our surveys documented two main habitat types: Acacia-Balanites-Boscia woodlands dominated by Acacia senegal, Acacia mellifera, Acacia nilotica, Boscia angustifolia, and Balanites aegyptica. The second kind of habitat consisted of the invasive Acalypha fruticosa and Indigofera arrecta with Acacia reficiens-Acacia brevispica overstorey. A total of 53 bird species were sighted and identified the vulnerable Yellow necked spurfowl (Francolinus leucoscepus). Seventy-nine percent of the birds were sighted as singles or in pairs except for the gregario

关键词： Habitat Avian Diversity Extinction Acacia Woodlands Rangelands

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Impact of Removal of Copper Leaf (<i>Acalypha fruticosa</i>Forssk.) on Plant Species Diversity and Abundance at Chemeron, Baringo County, Kenya

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Open Journal of Ecology 2020年第6期10卷 341-355页

作者： George Morara Ogendi Rhoda N. Ondieki Tabitha W. Njoroge Department of Environmental Science Egerton University Njoro Kenya dryland research training & ecotourism centre Chemeron Egerton University Njoro Kenya

Invasive plant species may significantly alter plant species community composition and structure thereby negatively impacting on ecosystem services. Their impacts on plant communities may be both direct and indirect. The direct effects may include a reduction in the abundance and diversity of palatable plant species that constitute important forage for livestock, wildlife, and medicines for the local communities. Declines in ecosystem resilience are of the notable indirect effects of invasive species. The aim of this study was to assess the impacts of a plant species, copper leaf (Acalypha fruticosa) on floral diversity and abundance at Chemeron, Baringo County in Kenya. The study was guided by three questions: What is the plant composition in terms of grasses, herbs, shrubs, and trees in the study area? Are there any variations in plant abundance between the two sites (sites with and without Acalypha fruticosa)? Are there variations in plant species diversity between the two study sites? Two sites (one with A. fruticosa and another two without this invasive species) were selected within the Chemeron research centre. Two belt transects measuring 100 m × 20 m on each site were laid parallel to each other. Plant samples were collected from five 1 m × 1 m quadrats that were laid at intervals of 20 m. The plant species or specimens were identified to the species level using available taxonomic keys. Various indices including Shannon-Wiener (H’), Evenness Index, Richness Index and Simpson’s Index of Diversity Index (SDI) were calculated. All the diversity, richness and evenness indices were considerably higher in the site without A. fruticosa compared to that where this invasive species was present. Higher H’ (3.14 to 3.21) and SDI (0.93 to 0.94) values were noted in sites without the invasive species compared to H’ (2.11 to 2.20) and SDI (0.77 to 0.85) in sites with A. fruticosa present. Out of the

关键词： Baringo Copper Leaf Diversity Indices Invasive Species Plant Diversity

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Land Tenure and Its Influence on Agriculture in Artisanal Gold-Mining Zones of Sikasso Region, Mali

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Open Journal of Ecology 2021年第2期11卷 95-104页

作者： Mahamadou Moussa Keita George Morara Ogendi Rural Polytechnic Institute for training and Applied research Katibougou Koulikoro Mali Department of Environmental Science Egerton University Njoro Campus Nakuru Kenya dryland research training and ecotourism centre Chemeron Baringo Kenya

Land tenure is a major determinant of the types of land use in a region or area and, by extension, affects its conservation. Most of the land that falls under public or communal land-tenure systems in developing countries such as Mali faces numerous challenges among them being natural resource overexploitation. This is mainly because the land is openly accessible to all people around it, and thus the tendency to overexploit the land resources leading to degradation, and food and environmental insecurity. In Mali, land ownership falls under three categories: Public or Government, Communal and Private. This study was undertaken to assess the land ownership types in Yanfolia District, Mali, a gold-mining area that lies some 170 km southern east of capital district of Bamako and upstream of Selingué dam on Sankarini River. A social survey of 200 households was done using a structured questionnaire. Additional research instruments were focus group discussion, key informant interviews and observation check-lists. The data was analyzed using both descriptive and inferential statistics. The study findings indicated that most of the land under gold-mining was owned by the government followed by community and finally private. There were significant associations between size of land under gold-mining and land tenure types: communal land (χ2 = 30.52;p = 0.000);private land (χ2 = 65.09;p = 0.000) and public or government land (χ2 = 177;p = 0.000). Gold-mining takes place mostly on lands classified under public/government and communal compared to that which takes place on lands classified as private. It is recommended that the relevant Malian governmental regulatory and enforcement agencies implement and enforce existing environmental laws with respect to land and environment. These agencies should adopt participatory and sustainable approaches to land and natural resources management for improved food and environmental

关键词： Land Gold-Mining Environment Agriculture Food-Security

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Application of Traditional Ecological Knowledge in Food and Water Security in the Semi-Arid Turkana County, Kenya

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Open Journal of Ecology 2020年第6期10卷 321-340页

作者： Cecilia Mwango Ratemo George Morara Ogendi Guangwei Huang Rhoda N. Ondieki Graduate School of Global Environmental Studies Sophia University Tokyo Japan Department of Environmental Science Egerton University Njoro Kenya dryland research training and ecotourism centre Chemeron Kenya

Weather extremes negatively affect socioeconomic developments in arid and semi-arid areas (ASALs) and increase vulnerability of residents to food and water insecurity. Thus, communities adapt to such extremes of weather using Traditional Ecological Knowledge (TEK) and/or Modern Technologies. Modern farming technologies and land resource developments in ASALs have in past ignored TEK, and in most cases led to undesired outcomes. It’s against this backdrop that this study was conceived to assess TEK among the Turkana people, its application and contribution to food and water security. The research adopted a cross-sectional social survey in collecting data from Central Turkana Sub-County residents. The study revealed that the Turkana people possess vast knowledge related to their environment;that this TEK plays a significant role in food production, preservation and in natural resource management. For instance, in 82% of the respondents use TEK in enhancing livestock production through the selection of livestock species that are suitable and drought tolerant;over 70% of them use TEK in reducing risk associated with livestock losses due to prolonged droughts. Further, TEK influenced the development and conservation of the water resources (r = 0.631;p < 0.01) including siting boreholes and wells. There was a strong correlation (r = 0.755;p < 0.01) between TEK and food security. TEK should be incorporated into the decision-making processes involving development projects within the ASALs.

关键词： Arid and Semi-Arid Lands Climate Variability Droughts Food Security Traditional Ecological Knowledge Water Security

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Effects of Land Use on the Riparian Vegetation along the Njoro and Kamweti Rivers, Kenya

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Open Journal of Ecology 2021年第11期11卷 807-827页

作者： Judith C. Koskey Charles M. M’Erimba George M. Ogendi Department of Environmental Science Egerton University Egerton Kenya Department of Biological Sciences Egerton University Egerton Kenya dryland research training and ecotourism centre Chemeron Egerton University Egerton Kenya

Riparian zones are valuable ecosystems. They act as the ecological engineers that improve river health by delivering a range of ecosystem functions. They play a significant role in river health and provide various ecosystem goods and services for human well-being. Currently, riparian areas are under threat due to intensive human activities such as agriculture and urbanization, which alter riparian ecosystem structure and composition. The main objective of this study was to determine the effect of adjacent land use on the structure and diversity of the riparian vegetation in the Njoro and Kamweti Rivers. Along each river, three sampling sites were selected within the major land use categories which were;forest, agricultural and built-up areas. At each site, three 70 m long transects were established perpendicular to the river. The three plots were systematically established, separated by a 5 m distance along each transect. Forest canopy cover was estimated in percentage. Njoro River riparian vegetation recorded a total of 145 plant species from 40 families where trees and shrubs were dominant in the forest area, and herbs dominated the agricultural and built-up areas. In Kamweti River riparian area, a total of 110 species from 45 families were encountered, in which trees dominated the forest area. A similar trend to the Njoro River was observed, in which herbs were dominant in the agricultural and built-up areas. In Njoro River, the Shannon diversity (H’) values ranged between 2.73 and 3.08 whereas Kamweti River riparian area values ranged from 2.59 to 3.40. At the level of P ≤ 0.05, T-Test revealed that there was no significant difference in plant abundance and diversity between the two rivers, with F = 0.53;P = 0.51 and F = 2.71;P = 0.17. Human-centered disturbances along the Njoro and Kamweti River riparian areas have affected the riparian vegetation as shown by the decrease in plant species diversities, and the change in vegetation composition and distribution ac

关键词： Land Use Riparian Vegetation Composition Distribution Diversity

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Assessment of Plant Commnunity Structure in a Tropical Wetland Affected by Brick Making—The Case of Sironga Wetland, Kenya

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Journal of Environmental Protection 2021年第11期12卷 1001-1008页

作者： Caren N. Atalitsa George M. Ogendi John M. Mironga Nicholas Olekaikai Department of Environmental Science Egerton University Egerton Kenya dryland research training and ecotourism centre Egerton University Egerton Kenya Department of Geography Egerton University Egerton Kenya Department of Natural Resources Egerton University Egerton Kenya

Brick making is one of the major small-scale industries in Sironga which has been expanding due to the growing demand for urban expansion. Due to the increasing population pressure, brick-making is competing for the wetland resources. Sironga wetland is threatened with serious degradation and probable loss of plant diversity. Conversion of this wetland for economic uses such as brick making has resulted in its loss. The objective of the study was to assess the effects of brick making on plant diversity in Sironga wetland. Nyamira County, Kenya. A one metre by one metre quadrat frame was laid down and perpendicularly recorded the percent cover for each species found inside the quadrant plus the percentage area covered by the bare ground litter. From each transect lines “diagonally” detailed vegetation under study was then done. The plant species were recorded and classified into three life-forms;herbs, sedges and grasses. The study revealed that grasses had the highest diversity H = 1.144. Diversity for herbs was H = 0.987 and H = 0.899 for reeds respectively. The study concluded that brick-making activities affected the plant diversity in Sironga wetland. This may be attributed partly to the limited information and awareness campaigns to the surrounding communities on the values and benefits of wetland ecosystem services and the lack of alternative livelihood sources. The study recommends that alternative livelihoods are provided and awareness campaigns on the values and benefits of wetlands to the residents are done by the relevant agencies.

关键词： Diversity Index Vegetation Types Environmental Degradation

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Characteristic Relationships between Phosphorous Accrual, Ecosystem Aspects and Water Level Fluctuations in Tropical Lakes: Naivasha Ramsar Site, Kenya

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Journal of Geoscience and Environment Protection 2021年第1期9卷 53-67页

作者： Beatrice N. Obegi George M. Ogendi Reuben Omondi Boston J. Siriba George N. Morara Nehemiah M. Rindoria Paul Orina Kenya Marine and Fisheries research Institute Naivasha Kenya Department of Aquatic and Fishery Sciences Kisii University Kisii Kenya Department of Environmental Science Egerton University Kenya dryland research training & ecotourism centre Chemeron Egerton University Kenya Department of Biological Sciences Kisii University Kisii Kenya Kenya Marine and Fisheries research Institute Kegati Kenya

Hydrological dynamics affect water levels and thus affecting ecosystem structure and functions. Lake levels in tropical ecosystems affect phosphorous input through runoff from adjacent watersheds. The resultant biological community, water and sediment quality of the lakes due to water level changes is a reflection of the geology of the area and the anthropogenic activities in the watershed. The study conducted between January 2018 and December 2019 was to explore relationships between the phosphorous input and Water Level Fluctuations (WLF) recorded by Water Resource Authority (WRA). Lake water samples were analyzed in the laboratory for phosphorous using molybdenum blue-ascorbic method and recorded using spectrophotometer. Chlorophyll-a was determined by extracting a filtered sample with 15 ml acetone and incubating overnight and thereafter read using a double beam spectrophotometer. Total Suspended Solids (TSS) was determined by filtering 200 ml of a water sample and dried overnight at 105°C. The lowest and highest phosphorous concentrations recorded were 0.2 mg/l and 0.42 mg/l at NST7 and NST2, respectively. Measurements of Chlorophyll-a were 0.32 mg/l and 0.42 mg/l at NST9 and NST2, respectively. Secchi transparency measurements were 32.9 cm at NST3 and 84 cm at NST1. The highest and lowest TSS concentrations were 0.14 mg/l and 0.13 mg/l at NTS1 and NST8, respectively. The hydrodynamic regime in most tropical lakes plays a significant role in the re-reaction of phosphorous that consequently influences productivity. Tropical lakes have extreme lake level fluctuations which accelerate the production process. The influence of water level changes on aquatic productivity is crucial in most tropical lakes and should be taken into consideration when assessing the environmental impacts.

关键词： Lake Level Fluctuations Total Phosphorous Ecosystem Aspects Lake Naivasha

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A new method for instant correction of numerical weather prediction products in China

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Science China Earth Sciences 2015年第2期58卷 231-244页

作者： ZHANG LanHui WANG ShiGong HE ChanSheng SHANG KeZheng MENG Lei LI Xu Brent M.LOFGREN Center for dryland Water Resources research and Watershed Science Key Laboratory of West China's Environmental System(Ministry of Education) Lanzhou University College of Atmospheric Sciences Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu ProvinceLanzhou University Department of Geography Western Michigan University NOAA/Great Lakes Environmental research Laboratory

This paper presents a new correction method, "instant correction method(ICM)", to improve the accuracy of numerical prediction products(NPP) and provide weather variables at grid cells. The ICM makes use of the continuity in time of the forecast errors at different forecast times to improve the accuracy of large scale NPP. To apply the ICM in China, an ensemble correction scheme is designed to correct the T213 NPP(the most popular NPP in China) through different statistical methods. The corrected T213 NPP(ICM T213 NPP) are evaluated by four popular indices: Correlation coefficient, climate anomalies correlation coefficient, root-mean-square-errors(RMSE), and confidence intervals(CI). The results show that the ICM T213 NPP are more accurate than the original T213 NPP in both the training period(2003–2008) and the validation period(2009–2010). Applications in China over the past three years indicate that the ICM is simple, fast, and reliable. Because of its low computing cost, end users in need of more accurate short-range weather forecasts around China can benefit greatly from the method.

关键词：天气预报产品数值预报产品中国即时 T213 预测时间校正方案相关系数

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Dynamics of forest biomass carbon stocks from 1949 to 2008 in Henan Province,east-central China

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Journal of Forestry research 2018年第2期29卷 434-443页

作者： Yanfang Wang Ling Liu Zhouping Shangguan State Key Laboratory of Soil Erosion and dryland Farming on the Loess Plateau Northwest A&F University College of Agriculture Henan University of Science and Technology

We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,*** to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub *** estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor *** used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub *** the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10;g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 *** stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub *** storageincreased at an average annual rate of 0.8 Tg carbon over the study *** was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory ***-leaved forest was the main contributor to forest carbon *** 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 *** results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program.

关键词： Forest biomass carbon stock Forest resource inventory Henan Province

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Land husbandry:an agro-ecological approach to land use and management Part 2:Consideration of soil conditions

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International Soil and Water Conservation research 2014年第4期2卷 64-80页

作者： T.F.Shaxson A.R.Williams A.H.Kassam Tropical Agriculture Association UK Pendragon dryland Management Services P/L Australia

This paper,complementing the first part(Shaxson et al.,2014),sketches the outlines of an ecologically-based approach to better care of soils,within the overarching context of‘land husbandry’,contributing to more-effective conservation of soil and *** suggests an up-dated paradigm which concentrates more on renewing and conserving the biologically-moderated spaces in the soil in the root-zone rather than on the solid soil-particles *** read in sequence,the two papers offer contributions to better understanding of both the problems and the possibilities for solving the ongoing uncertainties of how best to repair damaged lands,to maintain and improve those areas already in use,and to safeguard the potentials of those as-yet-unopened areas which surely will be brought into production in the future,by the planning and executing of optimum strategies for assuring sustainability of their uses into the *** two papers do not set out to challenge existing knowledge,but rather to suggest additions to,and alternative interpretations of,what may already be *** conclusions suggest some important amplifications to any curriculum for the training and/or up-dating of people involved in those subject-areas which contribute to better land husbandry and more-effective conservation of soil and water,as well as to the buffering of soils’productive capacities against the possible adverse effects of climate change.

关键词： Organic matter Soil porosity Paradigm-shift

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