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Soil Carbon Sequestration Differentials among Key Forest Plantation Species in Kenya: Promising Opportunities for Sustainable Development Mechanism
Vincent Onguso Oeba,
Samuel Chang Jwok Otor,
James Biu Kung’u,
Mbae Njugi Muchiri,
Larwanou Mahamane
Issue:
Volume 7, Issue 3, June 2018
Pages:
65-74
Received:
15 May 2018
Accepted:
14 June 2018
Published:
31 July 2018
Abstract: Soil organic carbon (SOC) contributes to the productivity of forests and enhances carbon sink in forest ecosystem. However, the available data on forest based carbon projects among African countries that have ratified Kyoto Protocol and are party to United Nations Framework Convention on Climate Change (UNFCCC) shows little emphasis on SOC, deadwood and litter. Kenya, for example, has piloted five afforestation and reforestation Clean Development Mechanism (AR-CDM) activities in government forests of which none addresses SOC, and yet studies elsewhere have shown that forest soils consist about 73 % of global carbon storage. This study therefore, sought to determine soil carbon sequestration differentials among selected key forest plantations in Kenya and their future implications on sustainable development mechanism. Soils were sampled at 0-20, 20-50 and 50-80 cm depth from Pinus patula, Cupressus lusitanica, Juniperus procera and Eucalyptus saligna/grandis plantations in Central Kenya for analysis of carbon, soil pH, nitrogen, phosphorous and potassium. The litter-fall collected from each of these forest plantations were analysed for nitrogen and carbon. The Pinus patula plantations had significantly (p<0.01) higher amount of soil carbon (132.2 ± 12.55 MgC ha-1) as compared with Cupressus lusitanica (114.4 ± 12.55 MgC ha-1) and Eucalyptus saligna (85.0 ± 12.55 MgC ha-1) plantations. Specifically, Pinus patula plantation had sequestered almost twice of soil carbon as compared to above and below-ground carbon pools whereas that of Cupressus lusitanica and Eucalyptus saligna /grandis were about 1.2 and 1.3 times higher, respectively. The levels of acidity varied among species, between and within sites from very strongly acidic to very slightly acidic. The amount of soil nitrogen, phosphorous and potassium between sites, tree species and soil depths differed significantly. This study therefore reveals soil carbon potentials in forest plantations that need to be considered in the development and implementation of afforestation and reforestation activities under Clean/Sustainable Development Mechanism (SDM). Equally, differences on soil carbon sequestered among species need to be taken into account when evaluating carbon stocks under certified and voluntary carbon offset markets in order to promote trees with high potential of carbon sequestration for sustainable development. This is important because, introduction of Reducing Emissions from Deforestation and forest Degradation (REDD+) and forest based Clean Development Mechanisms (CDM) have provided impetus to African governments in implementing afforestation and reforestation (AR) programmes to enhance carbon stock and improve resilience of biophysical and social systems against impacts of climate of change.
Abstract: Soil organic carbon (SOC) contributes to the productivity of forests and enhances carbon sink in forest ecosystem. However, the available data on forest based carbon projects among African countries that have ratified Kyoto Protocol and are party to United Nations Framework Convention on Climate Change (UNFCCC) shows little emphasis on SOC, deadwoo...
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Wheat Yields Under the Canopies of Faidherbiaalbida (Delile) A. Chev and Acacia tortilis (Forssk.) Hayenin Park Land Agroforestry System in Central Rift Valley, Ethiopia
Issue:
Volume 7, Issue 3, June 2018
Pages:
75-81
Received:
9 July 2018
Accepted:
21 August 2018
Published:
21 September 2018
Abstract: The study was conducted to evaluate the effect of Faidherbiaalbida and Acatiatortilis on the grain yield and above ground biomass of wheat. Parkland agroforestry system is, type of agroforestry where trees are deliberately retained on the crop land to improve soil fertility. Farm land of the study area is characterized by parkland agroforestry system. Farmers have different idea about the trees retained on their farm, some of them think that, these trees can help us for farm tools and fencing material while; others retained trees on the crop land for the purpose of fertility substitution. Therefore, the study was conducted to identify the effect of both trees on wheat growth. The study was conducted in central rift valley of Ethiopia, Oromia regional state, East shoa, at Langano and Tukakebeles in farm fields of Bora District where, both trees aretraditionally retained on the farm. At each site, four F. albida and four A.tortilis trees were purposively selected and wheat sample collected from four directions at three distances (1.35, 3.35 and 26.35 m) from tree trunk for both gain yield and above ground bio mass. Collected data was analyzed by two way ANOVA and mean separation with LSD (%). The Highest values of wheat grain yield were 73.33 and 68.85 kg ha-1 under F. albida and A.tortilis respectively at the distance of 1.35 m away from the6yuh tree trunks at Tuka location and these values decreased to 55.36 and 67.36 kg ha-1 under F. albida and A.tortilis respectively, at the distance of 26.35 m away from the tree trunks. The mean biomass recorded at three different distances from the two tree trunks, were not differently significant statistically (p >0.05). In general, the result of analysis indicated that, decreasing pattern of mean biomass as distance from tree trunk increases, for both Faidherbiaalbida and Acacia tortilis. The research finding showed that trees have positive relation with grain yield and above ground biomass of wheat. So, farmer’s knowledge improvement and further research regarding tree age class should be conducted for improvement of this agroforestry system.
Abstract: The study was conducted to evaluate the effect of Faidherbiaalbida and Acatiatortilis on the grain yield and above ground biomass of wheat. Parkland agroforestry system is, type of agroforestry where trees are deliberately retained on the crop land to improve soil fertility. Farm land of the study area is characterized by parkland agroforestry syst...
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Responding to Late Blight Disease Pressure and Fungicide Resistance Using Multiple Fungicide Active Ingredients and Different Spraying Regimes in Uganda
Arinaitwe Abel Byarugaba,
Mateeka Benon,
Tibanyedera Deo,
Barekye Alex
Issue:
Volume 7, Issue 3, June 2018
Pages:
82-88
Received:
16 February 2018
Accepted:
29 March 2018
Published:
26 September 2018
Abstract: Late blight (Phytophthora infestans) is one of the major diseases of economic importance limiting potato production in Uganda and causing yield losses of 40-60%. The emergence of more aggressive late blight pathotypes that are more difficult to control with ability to overcome host resistance or resist fungicide active ingredients has been noted in Uganda. Therefore, this study was carried out to identify suitable fungicides and spray regime for the effective management of late blight pathotypes on susceptible potato varieties in Uganda. Different fungicides that known to control late blight include Consento (Fenamidone 6.7% w/w + Propamacarb hydrochroride 93.6% w/w), Infinito (Propamacarb (55.3% w/w + Fluopicollide (5.53% w/w), Mancozeb (Dithiocarbamate 800g/kg), Agrolaxzyl (Metalaxyl 80 g/kg + Mancozeb 640 g/kg WP) were acquired from Bayer Crop Sciences and agro-inputs dealers in Uganda and tested for effective management of late blight on susceptible potato varieties in four different sites for two seasons (2015B and 2016A) using randomized complete block design (RCBD). Three (3) spraying regimes were tested and included; Bayer Crop Sciences recommended spray regime, current Uganda’s recommended spray regime, Hybrid (blend of Uganda’s recommended spray regime and Bayer recommendation) and no spray as control. Data on late blight disease severity was measured as percentage plant area affected (PLAA) and this was converted in to area under disease progress curve (AUDPC). The results showed that area under disease progress curve (AUDPC) ranged from 357-763 for the 3 different spray regimes while for the control (No spray), it ranged from 1895-2231. The late blight disease severity varied across sites and seasons, with Kalegyere site recording highest disease pressure in season 1 while Buginyanya had highest disease severity in season 2. Lowest disease pressure was registered with Bayer Crop Sciences based spray regime in season 1, while in season 2, hybrid spray regime registered lowest disease pressure. Use of multiple fungicide ingredients (Mancozeb (Dithiocarbamate 800g/kg), Consento (Fenamidone 6.7% w/w + Propamacarb hydrochroride 93.6% w/w); Infinito (Propamacarb (55.3% w/w + Fluopicollide (5.53% w/w) and Agrolaxzyl (Metalaxyl 80 g/kg + Mancozeb 640 g/kg WP) at different intervals has demonstrated the potential to suppress the disease to levels not causing serious economic damages by not allowing significant disease development on the leaves, hence has been recommended to be used for the management of late blight in Uganda.
Abstract: Late blight (Phytophthora infestans) is one of the major diseases of economic importance limiting potato production in Uganda and causing yield losses of 40-60%. The emergence of more aggressive late blight pathotypes that are more difficult to control with ability to overcome host resistance or resist fungicide active ingredients has been noted in...
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Determinants of Profitability of Fish Farming in Cameroon
Cynthia Jeh Mkong,
Ernest Lytia Molua,
Stephanie Mvodo
Issue:
Volume 7, Issue 3, June 2018
Pages:
89-93
Received:
8 June 2018
Accepted:
22 August 2018
Published:
26 September 2018
Abstract: Aquaculture remains an important source of food, nutrition, income and livelihoods for millions of people around the world. In Cameroon, like in most Sub-Saharan African countries, natural breeding and traditional fishing occur in virtually every river, lake and pond and the aquaculture sector predominantly comprises of small-scale producers with some larger-scale commercial activities. Although so many Cameroonian natives are involved in aquaculture, little profit is realized from their activities. Barriers to fish production include insufficient quality and quantity of fingerlings, inadequate quality of feed, inadequate financing and weak technical capacities. These problems lead to a core challenge of low supply of fish, coupled with low returns to fish farming and marketing. The study therefore sought to determine the level of profitability of fish farming and assess the main determinants of profitability of fish farming. It used data collected from 60 fish farmers in the Fako Division of Cameroon through personal interviews, using a pre-tested questionnaire. The study adopted net profit analysis to determine profitability and a Cobb-Douglas power function to quantify the effects of various factors on profit. The study found that fish farming is a profitable business with a mean net profit of 1 896 443 FCFA per production cycle of 4 months. Linear regression revealed that profitability of fish farmers was influenced by the price of feed, price of fingerlings and the cost of labor. The implications of the findings are that profitability can be enhanced by building the capacity of fish farmers on how to make fish production and marketing more cost effective. Farmers therefore need to know how to manage both variable and fixed costs in order to maximize profits.
Abstract: Aquaculture remains an important source of food, nutrition, income and livelihoods for millions of people around the world. In Cameroon, like in most Sub-Saharan African countries, natural breeding and traditional fishing occur in virtually every river, lake and pond and the aquaculture sector predominantly comprises of small-scale producers with s...
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