BC-School of Environmental Studies

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Using patterns of distribution and diversity of Kenyan birds to select and prioritize areas for conservation.
(Springer, 1996-01-14) Muriuki, J. N.; De Klerk, Helen. M.; Williams, P. H.; Bennun, L. A.; Crowe, T. M.; Berge, E. V.
Patterns and environmental correlates of species distributions and richness are identi®ed for Kenyan birds at a quarter degree-square scale. This information is used together with iterative complementarity analyses, which employ species richness, taxonomic dispersion and range-restrictedness, to identify priority areas for possible conservation attention. Bird species apparently not conserved by existing protected areas in Kenya are identited. Six avifaunal zones (and one transitional zone) are distinguished based on distributions of suites of bird species. Variation in biotope diversity (the number of forest and aquatic systems) accounts for 79% of the observed variation in Kenyan bird species richness. Although both rainfall and altitudinal range are signi®cantly correlated with species richness, they only explain an additional 3% of the observed variation. The priority areas identi®ed are situated mainly within highlands and coastal lowlands. Although few priority areas are identi®ed in northern Kenya, this region also constitutes a priority, as it contains a suite of xeric species with habitats that are not represented elsewhere in Kenya. The papyrus yellow warbler, Chloropeta gracilirostris, William's bush lark, Mirafra williamsi, white-winged dove, Streptopelia reichenowi, and Jubaland weaver, Ploceus dichrocephalus, are identited as endemics or near-endemics that are probably not adequately conserved in Kenya at present.
Soil Fertility Improvement Strategies for Increased Food Production in the Central Highlands of Kenya
(Soil Science Society of East Africa, 2000-01) Otor, S.C.J.; Mucheru-Muna, M.
Continuous decline in soil productivity is a major constraint to the improvement of livelihoods of smallholder farmers of Kenya. In highlands, levels of soil nitrogen, phosphorus and sometimes potassium are low and the situation is worsened by the methods of cultivation that results in nutrient mining rather than nutrient build up. Low soil fertility contributes to one of the greatest challenges currently facing Kenya; inadequate food production for the rapidly growing population. There is a need to seek for environmentally friendly and economically viable technologies to assist in soil fertility improvement and hence high and sustainable crop yields. To this end, a multidisciplinary research team of scientist and farmers implemented a participatory trial in Meru South district, one of the main maize growing areas of central Kenya. The trial was farmer-researcher managed with a general objective of offering small scale resource poor farmers with feasible soil nutrient management techniques for combating soil nutrient depletion caused by continuous cropping without adequate additions of external soil fertility inputs. Preliminary results indicate that maize performance may be improved by combining fast decomposing plant biomass (e.g. Tithonia diversifolia) with half the recommended rate of nitrogen fertilizer.
Adoption and adaptation of nutrient replenishment technologies by farmers in Kirege sub-location of Central Kenya
(African Crop Science Society, 2003) Mucheru-Muna, M.; Muriu, F.; Kung'u, J.B.; Karega, R.; Njuki, J.
Soil erosion, continuous cultivation, reduced land productivity, population pressure on land, low income, inappropriate and inadequate use of farm inputs such as fertilizers are some of the interrelated problems experienced by smallholder farmers in central Kenya highlands. These problems have been manifested in increased food insecurity in the area over the years. In an effort to address these problems research on soil nutrient replenishment technologies has been widely carried out in the area. Positive results(soil fertility improvement) have been reported from the use of tithonia, calliandra, leucaena, mucuna and crotalaria biomass. These technologies have been introduced to farmers in this area through participatory demonstration trial and on-farm trials to ensure that farmers benefit from knowledge generated through research. By the end 2003 short rains, two hundred and six (206) trained farmers had tested the soil nutrient replenishment technologies. A research was conducted to establish the criteria used by trained farmers of varying age and gender in their decision to adopt soil nutrient replenishment technologies. The study found out that farmers had adopted and adapted the soil replenishment technologies that were initially introduced to them. Use of calliandra and leucaena asincorporation materials had increased by 11% from the testing stage while 16% of the farmers preferred using the two tree species asfodder supplements. Preference of using calliandra had increased from 7% at the testing stage to 17%. Increased crop yield and otherfarmers’ experiences on improved soil fertility significantly influenced the farmers’ overall rating of the soil nutrient replenishmenttechnologies
Improved food production by use of soil fertility amendment strategies in the central highlands of Kenya
(Academy Science Publishers, 2003) Mugwe, J. N.; Mugendi, D.N.; Micheni, A.; Mugwe, J. N.; Kung'u, J.B.; Otor, S.C.J.; Gitari, J.; Mucheru-Muna, M.
Declining soil and crop productivity is a major problem facing smallholder farmers in eastern and central highlands of Kenya. This is caused by continuous cropping without addition of adequate external soil fertility inputs. A multidisciplinary and farmers participatory trial is being implemented in the main maize growing areas of the central highlands of Kenya to address the above problem. The trial is farmer-researcher managed with a general expected output of offering small-scale resource poor farmers feasible soil management techniques for combating soil nutrient depletion. Results for the two seasons reported here indicate that the general maize performance may be improved by combining fast decomposing plant biomass (e.g. Tithonia diversifolia) and half the recommended rate of nitrogen fertilizer.
The African Network for Soil Biology and Fertility: New Challenges and Opportunities
(Academy Science Publishers, 2004) Mugendi, D.N.; Bationo, A.; Kimetu, J.; Ikerra, S.; Kimani, S.; Odendo, M.; Silver, M.; Swift, M.J.; Sanginga, N.
Soil fertility degradation has been described as the single most important constraint to food security in sub-Saharan Africa (SSA). Soil fertility decline is not just a problem of nutrient deficiency but also of 1)Inappropriate germplasm and cropping system design. 2) Interactions with pests and diseases. 3) The linkage between poverty and land degradation. 4) Often perverse national and global policies with respect to incentives, and 5) Institutional failures. Tackling soil fertility issues thus requires a long-term perspective and a holistic approach. The African Network for Soil Biology and Fertility (AfNet)of Tropical Soil Biology and Fertility institute of CIATwhose ultimate goal is to strengthen and sustain stakeholder capacity to generate, share and apply soil fertility management knowledge and skills to contribute to the welfare of farming communities is devoted to overcoming this challenge. This African-wide network has over 200 members from National Agricultural Research and Extension Services (NARES) and universities from vanous disciplines mainly soil science. social science and technology exchange. This paper is an highlight of AfNet's main activities which include: Network field research activities. information and documentation. training and capacity building.
Soil Conservation and Fertility Improvement Using Leguminous Shrubs in Central Highlands of Kenya: NARFP Case Study
(CIAT,, 2004) Mugendi, D.N.; Mugwe, J. N.; Okoba, B.; Tuwei, P.; O’Neill, M.
Declining land productivity with reduced crop yields has been a major problem facing smallholder farmers in the central highlands of Kenya. The major factors contributing to the reduced land productivity is soil impoverishment caused by continuos cropping without addition of adequate fertilizer and manure, and soil erosion on steep slopes. The National Agroforestry Research Project (NAFRP) initiated research work in 1992 to try and address these problems. The research work investigated the potential of using two leguminous shrubs (Leucaena leucocephala and Calliandra calothyrsus) for improving soil fertility and soil conservation on steep slopes. The studies were carried out both at onstation and on-farm. Treatments where leafy prunings of calliandra and leucaena were incorporated yielded higher than the control treatments without prunings incorporation. Leucaena alley cropping system was beneficial and maintained crop yields at 4 t ha-1 in most seasons. Calliandra hedgerow intercropping system on the other hand depressed crop yields. However calliandra was effective in controlling soil erosion when planted as a contour-hedgerow system. The contour hedgerows in addition to conserving soil produced additional benefits in terms of high quality animal fodder. Ê This study concluded that in the central highlands of Kenya where land is slopy, and similar areas, it is advisable for the smallholder farmers to plant leguminous fodder trees on terraces as contour hedgerows for both soil conservation and biomass production. The resulting biomass could be incorporated into the soil to improve soil fertility for farmers without livestock, or fed to livestock for farmers who own livestock. If the biomass is fed to livestock, possibilities of recycling nutrient through animal manure should be explored to ensure soil nutrient replenishment.
Nitrogen Fertilizer Equivalency Values for Different Organic Materials Based on Maize Performance at Kabete, Kenya
(Academy Science Publishers, 2004) Mugendi, D.N.; Kung'u, J.B.; Kimetu, J.M.; Palm, C.A.; Mutuo, P.K.; Gachengo, C.N.; Nandwa, S.
Decline in crop yields has been a major problem facing small holder farming in Kenya and the entire sub-Saharan region. This is attributed mainly to the mining of macronutrients due to cropping without external addition of adequate nutrients. Inorganic fertilizers are expensive hence unaffordable by most small holder farmers. Although organic nutrient sources are available. information about the right proportions of application is scanty. An experiment was set up in 1999 at the National Agricultural Research Laboratories (NARL)at Kabete, with the overall objective of determining nitrogen fertilizer equivalencies based on high quality organic inputs. The specific objectives of the study included determination of the nitrogen fertilizer equivalency values of Tithonia diversifolia, Senna spectabilis and Calliandra ca/othyrsus and the investigation of nitrogen use efficiency from combined organic and inorganic inputs. The experiment consisted of maize plots to which freshly collected leaves of Tithonia diversifolia (tithonial, Senna spectabilis (senna) and Calliandra calothyrsus (calliandra) (all with % N >3) obtained from hedgerows grown ex situ (biomass transfer from outside) and urea (inorganic nitrogen source) were applied. Results obtained indicated that a combination ofboth organic and inorganic nutrient sources gave higher maize grain yield than when each is applied separately, except for tithonia whose sole application gave better grain yield than a combination of the same with mineral fertilizer. Maizegrain yield production after organic and inorganic application was in the order of tithonia > tithonta-urea = calliandra+urea > urea> senna-urea > calliandra > senna > control. The percentage N recovery was highest in sole application of urea followed by a combination ofboth urea and tithonia while sole application of tithonia biomass had relatively lower percentage N recoveries. In both seasons, the mineral Ncontent was high in sole application of tithonia than in senna and calliandra treatments. The three organic materials (senna, calliandra and tithonia) gave fertilizer equivalency values of 68%, 72% and 119% respectively.
Farmer participation in enhancing food productivity through agroforestry in the central highlands, Kenya
(African Network for Agroforestry Education (ANAFE, 2004) Mucheru-Muna, M.; Mugendi, D.N.; Kangai, R.; Kung'u, J.B.; Mugwe, J. N.; Otor, S.C.J.
Declining food production is a major concern in Kenya. This decline is brought about by continuous cultivation of soils without adequate external inputs. A multidisciplinary farmers' participatory trial aimed at offering farmers technologies for replenishing soil fertility. was established in the maize growing area of Meru South District of Kenya in 2000. Leafy tree biomass from leucaena, calliandra and tithonia effectively reduced the rate of soil fertility decline and improved maize yields. Attempts to expose farmers to these improved locally available technologies through field days have seen some impact in the study area, where farmers are already aware of their farming constraints and are willing to test and adopt these technologies that may regenerate or improve their farm productivity. During the 2002 long rainy season farmers in the study area were exposed to these technologies during field days, and some have adopted them to improve maize production in their farms. Seventy-six farmers were already working with these technologies and 36 more indicated willingness to try them on their farms during the 2002/2003 short rains
Gender-land degradation-livelihood nexus: lessonsfrom Ndome and Ghazi, Taita Taveta, Kenya
(African Network for Agroforestry Education (ANAFE, 2004) Waswa, F.; Mutheng, Kimanzi; Kutsch, Thomas
As the world continues to grapple with the realities of sustainable development, it is becoming increasingly acceptable that meaningful progress cannot be made without active involvement of women and the youth at critical levels of decision-making. Research and experience from Ndome and Ghazi in Taita Taveta in Kenya showed that marginalisation of women and the youth is still particularly high in household labour distribution, ownership of essential assets and production decision-making, resulting in persistent land degradation and household poverty. Further, gender insensitivity in these areas was ~ot based on ignorance on the part of men but was deliberate and had its foundation in deep-rooted sociocultural beliefs that gave men unfair advantage over women. Institutionalising gender equity is thus a critical requirement in building agricultural and natural resource capacity in Africa. Although simultaneous use of education, incentives and the rule of law are required in this endeavour, rapid positive change in Africa requires a 'needs-driven' and not a 'rights-driven' approach, as is common in developed countries
The place of agroforestry in the rehabilitation and utilisation of semi-desert environments of northern Kenya
(African Network for Agroforestry Education (ANAFE, 2004) Olukoye, Godfrey Alati; Wamicha, W. N.; van Eckert, M.; Kinyamario, I.; Mwanje, J. I.
Increasing destruction and degradation of the natural resource base in the sand-duned landscapes of North Horr, Marsabit District, northern Kenya, are jeopardising efforts towards sustainable economic development. The Gabbra nomads of the area live under severe poverty conditions. Effo~s to assessand apply agroforestry practices towards the rehabilitation and utilisation of the area's vast rangelands are at a formative stage. To this end silvopastoral systems have been formulated designed to ensure continued provision of fodder for livestock, improved soil fertility, provision of fuelwood, conservation of water resources and land rehabilitation. Suitable technologies including semi-desert plants such as Hyphaene coriacea for basketry and thatching of dwellings and Suaeda monoica for dry season browsing by camel are possible candidates for further development. The potential to domesticate wild plants for conservation purposes exists. Unfortunately direct planting of trees on communal lands within the study area is low. This paper examines the dual utilisation of agroforestry practices for land rehabilitation and enhancement of economic production systems in North Horr dry lands. Some of the factors that have hindered the effective application of agroforestry practices in the rehabilitation of the semi-desert environment of North Horr are also discussed. It is concluded that by addressing some of these factors and issues through community education programmes it would be possible to provide an effective framework for increased community participation for sustainable landuse management using suitable agroforestry techniques in semi-desert environments
Impact of soil nutrient management practices on plant parasitic nematodes of maize in central Kenya
(African Network for Agroforestry Education (ANAFE), 2004) Mugendi, D.N.; Waceke, J.W.; Mbaru, N.J.
Maize (Zea mays L.) is the staple food in Kenya. The current average production of 1.5-2 t per ha is far below the germ plasm potential of 3-7 t per ha. Low soil fertility, nematode and insect pests, diseases and poor quality of seed and advisory services are some of the maize production constraints in Kenya. However, there have been major efforts to overcome these production constraints in order to increase maize production. For example, useof animal manure and green manure alone or in combination with sub-optimal levels of inorganic fertilisers and interplanting maize with leguminous trees and shrubs are being recommended to farmers for replenishing soil nutrients. Some of these soil nutrient management strategies have negative or positive effect on plant parasitic nematode populations. The objective of the study was to assessthe impact of some of the soil nutrient management strategies on plant parasitic nematodes of maize, especially lesion nematodes (Pratylenchus spp.), which cause yield losses of up to 50% in maize. The soil nutrient management strategies whose impact on nematodes was assessed were mucuna and crotalaria alone, as intercrops or in combination with half the recommended rate of N fertiliser, and incorporation of cattle manure and green manure (Tithonia diversifolia, Calliandra calothrysus and Leucaena trichandra) singly or in combination with half the recommended rate of N fertiliser. Mucuna and crotalaria intercrops reduced nematode diseaseseverity and population by 20%. Addition of inorganic N fertiliser reduced efficacy of mucuna by 99% but not that of crotalaria against the nematodes. Incorporation of green manure had no effect or increased lesion nematode population and, consequently, diseaseseverity. In most cases addition of N fertiliser did not affect the effects of the green manure on nematodes. Cattle manure in combination with inorganic N reduced lesion nematodes and the associated disease severity by up to 75%.
Developing Agroforestry Curricula: A practical Guide for Academic Institutions in Africa and Asia
(World Agroforestry Centre, 2005) Rudebjer, P. G.; Temu, A. B.; Kung'u, J.B.
We promote the view that agroforestry is not only a set of practices, but also about the processes in society that influence, and are influenced by, those practices. Recent advances in participatory approaches are heavily influencing rural development paradigms and, in consequence, must also influence agroforestry teaching. By seeking the participation of farmers and other stakeholders, institutions are able to develop and deliver more relevant education programmes. We endorse and recommend the participatory approach here. Institutions use the terms 'subject', 'module' and 'course' interchangeably to describe the components of an education programme. For the purpose of clarity, we consistently use the term 'subject' in this guide. The term 'curriculum' is here used to describe all the teaching and learning content and processes that lead to a desired competence in learners. Thus we interpret 'curriculum' as a much wider concept than merely course subject matter. While agroforestry is taught in tropical, subtropical and temperate regions, this guide primarily targets users in developing countries, particularly those in Africa and Asia. However, institutions in other regions may also find it useful. The guide is organized into five Chapters. In Chapter 1, our introduction briefly looks back at agroforestry innovations over the past 25 years, and discusses different concepts o£ agroforestry and multifunctional landscape mosaics. We then look at the different scales of agroforestry research and development. Global experiences in agroforestry education are summarized in Chapter 2. After an overview of the history of agroforestry education, we discuss the diverse teaching approaches employed at different technical and professional levels. We then point out some of the common shortcomings of existing curricula. Finally, we briefly explore how the job market for agroforestry graduates has developed. Chapter 3 presents some commonly used methods for curriculum development. The participatory method is then discussed in some detail, because experience suggests that the participation of farmers, employers and other stakeholders helps create more relevant and applicable curricula. Agroforestry curriculum development is then discussed in Chapter 4. Based on the various processes available, we suggest a set of seven requirements for the planning and implementation of a curriculum development project. Methodologies for a simple training needs analysis and a stakeholder analysis are also provided. In Chapter 5, we present a framework for agroforestry curricula. This is intended to guide the content development within an agroforestry education programme, subject or topic. At the centre of the framework are farmers' decisions related to the agroforestry production cycle: overall management, the products and services produced, and the use and marketing of these outputs. We present a model of how these decisions are influenced by biophysical and socioeconomic conditions, and how agroforestry practices may impact on people and landscapes. We also discuss risks and potential challenges, and how policies and governance relate to agroforestry. Finally, we offer some additional resources. Firstly, we present Internet resources related to agroforestry, natural resources management and education. Secondly, Annex 1 presents a quick reference summary of the complete agroforestry curriculum framework.
Urbanisation Challenges in Kenya
(School of Environmental Studies and Human Sciences, Kenyatta University, 2006) Mireri, C.
Kenya has witnessed rapid rate of urbanisation (about 6%) since independence in 1963. The independence guaranteed people freedom of movement, which spurred high rate of rural urban migration. Against the rapid urban growth the country has registered deterioration of institutional and physical infrastructure. As a result, Kenyan urban centres are characterised with expansive informal settlements; poor water and sanitation infrastructure and services. Also, the 1990s ushered in increasing incidences of poverty, a situation that threatens to heighten in future. Currently, over 60% of Kenyans live below the poverty line (SID, 2005). Theurbanisation in Kenya is explained in large measure by the growth pole theory. Further, the urban development policies in the country are founded on the theory. Kenyan urban hierarchy is characterised with one metropole (Nairobi city) together with a limited number of major urban centres (Mombasa, Kisumu, Eldoret, Nakuru and Thika). The various strategies used by the government to catalyse urban development have largely failed. Therefore, there is need to rethink urban development strategies to arrest the inevitable crises that are likely to ensure following policy failures and strategies. This chapter explores the following issues: theoretical and policy perspective; demographic profile; planning, infrastructure and services and institutional framework. _
Potential of Dryland Farming in Kenya and Environmental Implications
(School of Environmental Studies and Human Sciences, Kenyatta University, 2006) Waswa, F.; Mburu, John
With the arid and semi-arid lands (ASALs) accounting for more than 70%of Kenya's total land area, and supporting an increasing population of both humans and animals, investment in water resources development will be a critical research and policy agenda for national development. From 1998 to date, devastating droughts have been persistent in Kenya to the level of being declared national disasters. Drought events translate into severe soil moisture deficits, far below crop and pasture water requirements. Often this is followed by crop failure and hence hunger, famine, livestock deaths and general human suffering. By way of intervention, government has often responded by focusing on short term measures like appealing for food aid, which in essence is a reminder of urgent policy re-orientation that would make ASAL areas self-sufficient when it comes to guaranteeing people's basic needs like food. A look at previous drought incidences in Kenya seems to suggest that although such climatic phenomenon are stochastic, drought should be expected every after about 4 years (Table 5.1). As such planning for lasting solutions should be possible instead of addressing symptoms on a routine basis .. With more than 20 devastating drought events already experienced, yet no viable counter-strategy to date, Kenya seems to either lack the relevant policy framework and or necessary political will to implement workable solutions. This too calls for research into possible causes of inaction to inform future decision-making. Besides scarcity of water, the ASALS also exhibit inherent characteristics that make them fragile ecosystems deserving careful management options in order to maximise on their agricultural potential (Table 5.2). Further, Barron and Rockstrom (2003) observed that contrary to conventional thinking, the dry lands are not absolutely deficit of water especially when it rains, but rather suffer from poor rainfall distribution and poor land and water management. As such, ASALdevelopment is hinged upon an integrated approach that focuses on its inherent limitations.
Understanding and Managing Eco-Conflicts and Environmental Insecurity
(School of Environmental Studies and Human Sciences, Kenyatta University, 2006) Waswa, F.
The word conflict is commonly used in everyday speech to label various human experiences, ranging from indecision, disagreement and stress. A conflict situation thus contains the following four elements; a condition of interdependence between the concerned stakeholders, feeling of anger, a situation where one party views the other as being at fault and actions that cause "business" problems. A Conflict can also be defined as the competition between interdependent parties, who perceive themselves as having incompatible needs, goals, desires or ideas (Robbins and Colter, 1996). It is a situation in which people cannot agree or create harmony with one another. There are different kinds of conflicts: social, economic, industrial, political, and occur at different levels (community, regional, country, continental and international). Understanding their nature (structure) is important in designing appropriate resolutions for them. The focus of this chapter is ecological conflicts also referred to as resource use or eco-conflicts. Ecological conflicts stem from.the need to access, control, own, use and benefit from natural resources (Nature's "free" goods and services), such as land, water, climate, minerals, fauna and flora. In an-ideal situation, all people should have equal access to them. In practice, prevailing economic and political systems have not allowed this to happen. Instead, these resources have been reduced to commodities for generating profits in total disregard of social justice and equity. The result of this scenario particularly in capitalist nations is extremes of those who have and those who have not, and hence conflicts with subsequent negative impacts to the total environment and human well-being. Some common effects of conflicts and security concerns include among others: • Loss of human life in the event of clashes or war • Loss of livelihood when economic and social systems are disrupted • Political instability • Proliferation of refuges and internally displaced persons • Destruction of infrastructure and hence loss of economic opportunities • Increased human trauma and consequent disorders
Opportunities and Challenges for Sustainable Agricultural Land Management in Kenya
(School of Environmental Studies and Human Sciences, Kenyatta University, 2006) Waswa, F.
Despite technological advances in land management (i.e. use, care and improvement) across the world, land degradation not only persists, but also continues to escalate, thus threatening the livelihood of many agriculturally dependent communities. Projections of world food situation into 2020for instance singles out potential scarcity of maize - an important cereal in Kenya, whose demand will have to be met by a 40% increase in grain production, however on a steadily deteriorating land resource (Pinstrup-Andersen et al., 1999). Estimates from the Global Assessment of Soil Degradation (GLASOD) indicate that degradation of crop land and pasture land is most extensive in Africa, affecting 65% and 31%of the two systems respectively (Scherr and Yadav, 1996). In Kenya, 73% of land degradation is attributed to overgrazing and arable agriculture, while conversion of arid and semi-arid lands to other uses accounts for some 14% of land degradation (Mutiso, 1991). With increasing population pressure, only little evidence exists to indicate that this condition may after all not be disadvantageous as conventionally understood (Tiffen et al., 1994). In the past, soil erosion and subsequent fertility decline, diminution of agricultural productivity and decline in environmental quality were normally attributed to the effect of natural phenomena like climate. Emphasis on the attainment of optimum resource management and productivity was thus put on biophysical factors, which however was met with little success as earlier mentioned. This indicated that other factors hitherto ignored were equally critical. Therefore, since the 1980s, there has been growing recognition that persistent land degradation results from the failures on the part of conventional research, policy and development approaches to recognise the importance of the participation of the land users and the total human dimension at all levels of decision making in resource management. Further, programmes with spontaneous support of the target group stood a better chance of success, especially when such interventions were accompanied with tangible short-term benefits (FAO, 1995; Mcclelland, 1998;Steiner, 1998). However, a considerable gap still exists between conceptual acceptance and real implementation on the ground. Widespread failure on the part of the target groups to adopt what would be appropriate technologies (Fujisaka, 1994, Ashby et al., 1996; Thomas, 1996) and tendencies of II experts" to address symptoms rather than root causes and hence persistence of land degradation in many tropical agro-ecosystems attests to this
Application of Ecosystem Modelling in Environmental Management in Kenya
(School of Environmental Studies and Human Sciences, Kenyatta University, 2006) Olukoye, Godfrey Alati
Ecosystems are dynamic entities made up of several interactive biotic and abiotic factors that determine their production and productivity levels. Equally complex are the ecological processes that govern ecosystem structure and function, the inherent variability in biophysical processes and the interactions between ecological, economic and social processes. Models that seek to guide policy decisions need to capture this complexity. Equally important, managers should give due consideration to the prevailing economic, socio-cultural, legal and political factors that may be relevant when making appropriate management decisions. Although the management of ecosystems is difficult, various models have been developed that aid in decision making for sustainable ecosystem management. For example, conceptual models that incorporate the interactions of climate, plants and herbivory are important in understanding land use dynamics. Further, establishing a balance in ecological and economic functioning of resources such as vegetation in an ecosystem is difficult but ecosystem models have the capability to simulate such complex scenarios to arrive at appropriate resource management. Simulations help in the diagnosis of strengths and weaknesses of an ecosystem and compare it with other alternatives so that improvements may be prescribed (Upton, 1989). Despite this advantage, simulations and their use in resource management especially in developing countries is rare
The Potential Role of Life Cycle Approaches in Sustainable Development
(School of Environmental Studies and Human Sciences, Kenyatta University, 2006) Kituyi, E.
Africa remains one of the most underdeveloped continents in the world. In the struggle to attain economic and social development, the region has _ witnessed serious unsustainable patterns of consumption and production (WSSD, 20021). In Africa in particular, the abstraction and conversion of natural resources such as minerals and forests, as well as processing of agriculture-based commodities potentially present the biggest concern for material and energy losses. It is on these sectors that economies and livelihoods of most countries in Africa depend. The unsustainable patterns of production and consumption have been attributed, first, to the piecemeal nature of interventions to environmental management, characteristic in many developing countries. Secondly, Agenda 21-the action plan towards sustainable development adopted by governments in Rio a decade ago-did not define a strategy or even provide guidance on how governments may develop one (OEeD, 2002). Thirdly, despite increasing recognition of the role of science, technology and innovation in the economic transformation of developing countries, their prominence in national development policy is generally understated". As a result, there have been massive losses of materials and energy at points of resource extraction, processing, consumption and disposal. Furthermore, much of this loss has contributed to environmental pollution on land, air and water bodies, rendered land unusable for food production due to pollution or desertification. The obsolete technology employed and the inadequate capacity to apply international quality standards in most of these production and consumption processes are largely to blame for the poor quality of goods that have frequently failed to compete on global commodity markets such as the European Union. Many export oriented small and medium scale enterprise (SMEs) have closed down with resultant massive job losses. Ironically, these challenges exist at a time when holistic, science based innovations exist. And the WSSD called for the development of policies for sustainable consumption and production using science based tools and approaches. For instance, Industrial Ecology-also known as the science of sustainability, and defined in this chapter as the study of the flows of materials and energy in industrial and consumer activities, of the effects of these flows on the environment, and of the influences of economic, political, regulatory and social factors on the flow, use and transformation of resources' - is among the latest important contributions by science in pursuit of sustainable development. Industrial ecology-related tools include inter alia Design-for-Environment (DfE), industrial symbiosis and Life Cycle Approaches. This chapter explores the potential in Life Cycle Approaches as a sustainability tool for Africa.
Energy for Sustainable Development
(School of Environmental Studies and Human Sciences, Kenyatta University, 2006) Kirubi, C.
The concept of sustainable development refers to development that 'meets the needs of the present without compromising the ability of future generations to meet their own needs' (WCED, 1987). This has social, economic and environmental dimensions. The way energy is produced and used plays an essential role in all the three dimensions. Current primary energy sources are shown in Figure 3.1. The energy system today is heavily dependent on the use of fossil fuels (coal, oil and gas), which together account for 80%of global primary energy consumption (Johansson and Goldemerg, 2002). It is clear that countries differ significantly in the structure of their energy consumption (Figures 3.2-3.4). Fossil fuel consumption accounts for 83%of the energy consumed in industrialized countries and 93% in the transition-economy countries, but only 70%in developing countries. In contrast biomass represents only 3.4% of primary energy used in industrialized countries, is virtually non-existent in countries in transition, and accounts for 26% of energy used in developing countries. Nuclear energy is also significant in industrialized countries (where it is the source of 11% of primary energy) and countries in transition (5%), but makes only a minor contribution in developing countries (1%). The figures also highlight the extreme inequalities in per capita use among groups of countries. Industrialized countries use 4.7 tons of oil equivalent (toe) per capita, in contrast to developing countries, which use only 0.78% toe per capita; the world average is 1.6 toe per capita.
Environment and Sustainable Development Nexus
(School of Environmental Studies and Human Sciences, Kenyatta University, 2006) Waswa, F.; Otor, S.C.J.; Mugendi, D.N.
To appreciate the link between the environment and sustainable development, one needs to understand the basic concepts within ecology. While numerous literatures exists on this subject, ecology generally refers to the scientific study of the inter-relationships between living things and their biotic and abiotic environment, which determines the distribution and abundance of organisms in an environment (Krebs, 1985). On the other hand, the environment according to Kenya's Environmental Management and Coordination Act (EMCA) 1999 includes the physical factors of the surroundings of human beings including land, water, atmosphere, climate, sound, odour, taste, the biological factors of animals and plants, and the social factor of aesthetics, and includes both the natural and the built environment. In essence the environment may be viewed as the totality of nature and its components. Current thinking no longer views ecology as a subdivision of biology, but acknowledges that it has emerged from its roots in biology to become a separate discipline that integrates organisms, the physical environment, and humans on the premise that everything on earth operates in cycles, and all life is connected (Odum, 1996). Various specializations in ecology have emerged and will continue to emerge as humans continue to discover new areas in the environment for utilization. As an emerging specialisation, and based on the role of humans as the greatest force in shaping and being shaped by the environment, human ecology is the study of humans as they relate to the environment. It includes the study of the impact of humans on the environment and vice versa, as a basis for informed and accountable decision-making about resource use and development towards sustainable societies. Prior to the development of ecological thinking, science had been reductionist and concerned with compartmentalizing things in order to understand them. To the contrary, ecology is holistic and requires a study of the whole, which is often more than the sum of the parts. Ecology thus involves many branches of science and must inevitably adopt an interdisciplinary and integrated approach, which in essence simulates diversity and the inter-dependence of nature and its components. It is on this basis that mainstreaming sustainability thinking in education has gained momentum within the international community (UNEP, 2006).

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