The focus of the West African Journal of Applied Ecology is on ecology, agriculture and water pollution.

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The Globethics.net library contains articles of the West African Journal of Applied Ecology as of vol. 1(2000) to current.

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  • Awortwi et al.: Mixing and stratification relationship on phytoplankton of Lake Bosomtwe (Ghana) 43 West African Journal of Applied Ecology, vol. 23(2), 2015: 43–62. The Relationship Between Mixing and Stratification Regime on the Phytoplankton of Lake Bo

    Awortwi, F.E.; Frempong, E.; Aikins, S. A.; Hecky, R. E.; Hall, R.; Puchniak, M. (Ecological Laboratory Unit, University of Ghana, 2016-02-15)
    The seasonal changes in the phytoplankton community in terms of biomass composition and associated physicochemical parameters of the Lake Bosomtwe (Ghana) located in West Africa were studied between 2004 and 2006 to assess the mixing and stratification regime of the lake on the phytoplankton dynamics. From water samples obtained from a central index station, biomass composition was assessed by converting phytoplankton counts to wet weights-based approximation into cell volume values; whiles mixed layer and euphotic depths were analyzed using temperature and light profiles of the lake respectively. Total phosphorus was estimated using the Ascorbic Acid Method. Results from the dataset showed that the phytoplankton biomass was dominated by the Cyanophyceae throughout the study period despite the seasonal changes associated with the mixing and stratification regimes. There were significant inter-annual differences in the mean values of the euphotic depth and the wet weight biomass (P < 0.05). However differences in the mean values of the mixed layer depth, the ratio of the mixed layer depth:euphotic depth, and total phosphorus concentration (P > 0.05) were insignificant. High variations in the mixed layer depth (CV > 34 %) and the euphotic depth (CV > 32) drive similarly high variations in the wet weight biomass (CV > 28) as is the case for many stratifying tropical lakes. However, both were poor predictors of the phytoplankton wet weight biomass behaviour (mixed layer depth, r2 = 0.1034; euphotic depth, r2
  • The Impact of Harvest Frequency on Herbage Yield and Quality of Cynodon nlemfuensis

    Timpong-Jones, E.C.; Adjorlolo, L. K.; Ayizanga, R. A. (Ecological Laboratory Unit, University of Ghana, 2016-02-15)
    Ruminants in Ghana experience feed deficit in the dry season leading to loss of weight and condition. To curb this problem of weight loss, there is the need to raise their plain of nutrition in the critical months of the year when feed is low in quantity and quality. This can be achieved by maximising forage production through appropriate harvest management practices. This study sought to find the effect of repeated harvest on dry matter (DM) yield of Cynodon nlemfuensis (Cynodon) in the coastal savanna of Ghana. It was hypothesised that infrequent repeated harvest will improve DM yield and nutritive value of Cynodon. An area of 7.0 m by 5.5 m was used for a two year study (2013 and 2014). The treatments were harvest of Cynodon at 24 (T1), 12 (T2) and 6 (T3) weeks intervals. The Randomised Complete Block Design was used with four replicates per treatment. Dry matter yield and plant cell wall constituents viz. NDF, ADF and Cellulose contents decreased significantly (P < 0.05) in the order T3<T2<T1, indicating that DM yield and plant cell wall constituents decreased with increasing harvest frequency. Crude protein content (CP) decreased significantly (P < 0.05) in the order T1<T2<T3, indicating that CP content increased with increasing harvest frequency. The study has shown that repeated harvest of Cynodon provided lower DM yield of better quality, with harvest at six weeks interval exceeding the minimum CP level required for adequate intake and digestibility by ruminant livestock.
  • Diversity and response of Benthic Macroinvertebrates to Natural and Induced Environmental Stresses in Aiba Stream, Iwo, Southwestern Nigeria

    Akindele, EO; Liadi, AA (Ecological Laboratory Unit, University of Ghana, 2014-09-19)
    Aiba stream, a tropical stream in southwestern Nigeria, was investigated on monthly basis from November 2012 to April 2013 with a view to comparing their response with the Biological Monitoring Working Party (BMWP) score system already in use in some eco-regions. The diversity and response of benthic macroinvertebartes were used in assessing the biological water quality and health status of the stream. Samples were collected from four different stations using the Kick Sampling Technique. All the specimens collected were preserved in 70% alcohol solution and later identified in the laboratory using relevant identification guides. Predatory invertebrates like water scorpions (Nepa and Rana spp.) and dragonfly nymphs (Macromia sp.) were sorted out in-situ and stored separately. Nineteen taxa of macroinvertebrates were recorded comprising three Phyla, four classes and 17 families. The overall Shannon-Weiner diversity and Margalef’s indices of the stream indicated that the stream was organically polluted, as evidenced by the presence of some pollution-tolerant macroinvertebrates (e.g. Families Stratiomyidae, Nepidae, Planorbidae, Chironomidae and Syrphidae). Although there were some similarities between the BMWP score system and the response of the benthic macroinvertebrate families to environmental stress, a disparity was also observed between the two which underscores the need to carry out intensive research in this regard and adapt a BMWP score system for regional freshwaters in the tropics.
  • Aboagye et al.: Anthelmintic effect of Moringa oleifera in Achatina achatina 27 West African Journal of Applied Ecology, vol. 23(2), 2015: 27–33. Anthelmintic Effect of Moringa oleifera Lam. in Wildcaught Achatina achatina Linnaeus, 1758 from the Sefwi Wi

    Aboagye, I.F.; Mensah, D; Boadu, F (Ecological Laboratory Unit, University of Ghana, 2016-02-15)
    Parasitic infection in edible snail species such as Achatina achatina has the potential of reducing growth and requires investigation.This study assessed the anthelmintic effect of Moringa oleifera in A. achatina. Using dissecting and microscopic techniques, the proportion of parasitic infection in A. achatina group fed with M. oleifera was significantly lower than that of the control group (χ²(1) = 14.97; P = 0.0001). The mean parasite intensity recorded for the kidney of both treated (2.17) and control (3.33) groups of snails were significantly different (bootstrap t = 2.31; P = 0.041). Similar observation was made in the lung of treated (1.43) and control (3.14) snail groups (bootstrap t = 3.54; P = 0.005). However, no significant mean parasite intensity in the spermoviduct of treated (1.80) and control (1.96) snail groups was observed (bootstrap t = 0.475; P = 0.627). The results generally highlight anthelmintic value of M. oleifera in the control of parasites in A. achatina. Fresh foliage of M. oleifera may serve as useful addition to the feed of reared edible snails.
  • Comparison of Several Methods to Estimate Reference Evapotranspiration

    Zarei, AR; Zare, S; Parsamehr, AH (Ecological Laboratory Unit, University of Ghana, 2016-02-15)
    Evapotranspiration is one of the major components of the hydrologic cycle is highly important in studies relevant to design and management of irrigation systems. The knowledge of the evapotranspiration of natural ecosystems and plant populations is of fundamental importance in several branches of science, research and practical uses. Nevertheless, the harmonization of the large number of methods and user needs often causes problems. The aim of these analyses was to explore the output range and sensitivity of models of different physical approaches under local conditions. In this study, evapotranspiration (ET0) was determined by several models include: Penman-Monteith-FAO-56, Blaney-Criddle, Hargreaves-Samani modified 2, Pan Evaporation, Jensen-Haise and Thornthwait in the Garebayegan research station at Fars province. Penman- Monteith-FAO-56 was reference model. Results of this research show that Pan Evaporation method, Hargreaves-Samani modified 2 and Blaney-Criddle have not significant difference by Penman-Monteith- FAO-56 in (P value< 0.05 level). Pan Evaporation method has most similarity to Penman-Monteith-FAO-56. Jensen-Haise and Thornthwait models have significant difference by Penman-Monteith-FAO-56 in (P value< 0.01 level). Thornthwait model has most difference by Penman-Monteith-FAO-56.
  • Cross-resistance assessment in cartap- and esfenvalerateselected strains of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae)

    Ninsin, KD (Ecological Laboratory Unit, University of Ghana, 2016-02-15)
    Effective control of the diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae) has become critical due to the genetic ability of the insect pest to develop resistance to insecticides. Alternating or rotating the use of insecticides that do not show cross-resistance is an important component of an effective resistance management strategy, as it helps prevent resistance development or regain susceptibility in an already resistant arthropod pest population. In this study, cross-resistance to selected insecticides in cartap- and esfenvalerate-selected strains of DBM was assessed in the laboratory, using the leaf-dipping method. The esfenvalerate-selected strain exhibited moderate cross-resistance to abamectin and a very low cross-resistance to cartap. The cartap-selected strain also displayed a very low cross-resistance to esfenvalerate but showed no cross-resistance to abamectin. Alternating cartap and abamectin would therefore help to effectively manage insecticide-resistance development in the DBM.
  • Effect of Duration of Reclamation on Soil Quality Indicators of a Surface – Mined Acid Forest Oxisol in South – Western Ghana

    Tetteh, E. N.; Logah, V.; Twum-Ampofo, K.; Partey, S. T. (Ecological Laboratory Unit, University of Ghana, 2016-02-15)
    The quality of degraded mined soils can be restored through effective reclamation practices. In this study, we evaluated the impact of varying duration of land reclamation on soil quality at AngloGold Ashanti, Iduapriem mine Ltd., Tarkwa, Ghana. Soil samples were taken from mined sites of the Company at various stages of phytoremediation: 2, 5, 9 and 11 year old reclaimed sites. The soils were analyzed for soil quality indicators. A nearby forest reserve representative of the pre-degraded condition was used as the control. Prior to phytoremediation with multipurpose agroforestry trees, the mined soils were subjected by the Company to earthworks/slope battering followed by spreading of oxide materials over the surface, construction of crest drains and cover cropping. Having determined the impact of the varying duration of reclamation on soil quality indicators, separate pot experiments involving maize and cowpea were set up using soils from the sites to assess heavy metals accumulation in the cultivated crops. Soil nutrient levels in the sites under reclamation were significantly higher (P < 0.05) than the nearby forest reserve. Soil pH though generally low, was relatively higher (P < 0.05) in sites under reclamation than in the control. Soil total nitrogen, available phosphorus and exchangeable potassium levels were highest (P < 0.05) in the 11 year old site. Zinc contents of all sites were below the maximum permissible levels. There was somewhat antagonistic interaction between zinc and phosphorus contents of maize in the unclaimed site. Though heavy metal concentrations in maize were lower than that of cowpea, the concentrations in both plants were generally beyond the permissible levels suggesting a possible transfer onto the food chain if the crops are included as part of rotation programmes from the agronomic perspective. Our results indicate that phytoremediation of mined lands using agroforestry multipurpose trees could be marginal even after a decade of reclamation.
  • A Survey of the Benthic Macrofauna and Fish Species Assemblages in a Mangrove Habitat in Ghana

    Tawiah, P; Longdon-Sagoe, M; Okyere, I; Dotsey-Brown, J; Asare, NK; Aheto, DW; Wemegah, Y; Dzakpasu, MFA (Ecological Laboratory Unit, University of Ghana, 2014-09-19)
    In order to enhance ecological knowledge for coastal and mangrove  ecosystem conservation in Ghana, the study documents the taxonomic groups of benthic macrofauna and fish assemblages in an urban mangrove swamp as its fundamental objective with emphasis on their composition, richness and diversity. This is because benthic and fish fauna of mangrove habitats are amongst the least studied biota in Ghana. Fish and benthos sampling was undertaken from five randomly selected pools within a mangrove stand during the wet and dry seasons using pole-seine net (7 m long and 1.5 m depth, with stretched mesh size of 5 mm) and an Ekman grab (15 cm × 15 cm dimensions), respectively. All samples were  preserved in 10% formalin for laboratory analysis. The results indicated a more diverse macrozoobenthic community in the wet (H¹ = 1.8) than dry season (H¹ = 1.5) . Overall, five out of a total of 13 genera found are intolerant to pollution and four moderately tolerant, while four comprising polychaetes and the midge Chironomus, are pollution tolerant. This suggests that the mangrove habitat is less polluted. A grand total of 917 fish specimens, belonging to 15 species and nine families, were encountered for both seasons (371 and 546 specimens for wet and dry seasons, respectively). The black-chinned tilapia, Sarotherodon  melanotheron, was the dominant fish species in the wet season, accounting for 54.2% of the total fish caught, whilst the grey mullets, Mugil babanensis and Mugil curema, were the dominant species in the dry season, with a combined total of 51.4% of the fish population. However, over 70% of these dominant fish species from both seasons were juveniles providing a strong justification for the observation that the mangrove habitats are nursery grounds for fish inhabiting adjacent riverine, estuarine and inshore marine habitats. Considering this relevance of mangroves and the ongoing conversion attempts of mangrove habitats to other land uses, a concerted mangroves conservation effort is strongly advocated.
  • Assessing the Efficacy of Azadirachta indica Seed Extract on Fusarium Oxysporum

    Oladipo, OG; Ogunkanbi, D.A.; Ayo-Lawal, R. A. (Ecological Laboratory Unit, University of Ghana, 2016-02-15)
    Global population pressure has posed great challenge on food security with over 800 million people having no access to adequate food and about two billion faced with hunger and malnutrition. Banana (Musa spp.) is the world’s fourth most important global food crop after rice, wheat and maize in terms of production. The cultivation of banana is however threatened by pests and diseases and diverse anthropogenic activities which have influenced and changed the climate. Generally, climate change impacts on agriculture and food security across the globe decreasing crop productivity while extreme weather conditions such as flooding, drought, hurricanes etc. increase disease transmission. Fusarium oxysporum, a soil borne fungus affects banana production, causing vascular wilts and damage to banana plantations by infecting plant roots, cortex and stele. Several fungicides have been employed to curb these losses. Plant extracts have, however, played significant role in the inhibition of seed-borne pathogenic F. oxysporum. Eco-friendly Neem (Azadirachta indica) extracts have been reported to gain prominence over inorganic fungicides. This study investigated the effectiveness of Neem (Azadirachta indica) seed extract at varying concentrations of 10, 20 and 50% against F. oxysporum in Potato Dextrose medium for 120 h. using pour plate and cork boring methods. The results obtained showed inhibited growth of the test fungus with 50% having the greatest percentage inhibition. This indicates that A. indica seed extract has fungicidal effect on F. oxysporum and has the potential to curb banana losses and hence enhance banana production and thus ensure food security.
  • A Theoretical Study of Subsurface Drainage Model Simulation of Drainage Flow and Leaching in Salt Affected Irrigated Fields

    Ampofo, EA; Tanton, TW (Ecological Laboratory Unit, University of Ghana, 2014-09-19)
    A three-dimensional variable-density groundwater flow model, the SEAWAT model, was used to assess the influence of subsurface drain spacing, evapotranspiration and irrigation water quality on salt concentration at the base of the root zone, leaching and drainage in salt affected irrigated land. The study was carried out on a conceptual uniform homogenous irrigated field of shallowwatertable depth of 0.5m and aquifer salt concentration of 7200 mg/l with an impermeable layer at 10 m depth and impermeable field boundaries. The model was run for 10 years with an irrigation rate (applied recharge) of 8 mm/d and salt concentration of 1,500 mg/l, over a range of drain spacings. During the 10-year drainage period, the simulated concentrations at the base of the root zone and the discharge rates were the same at all the spacing when evapotranspiration was not included. However, upon inclusion of evapotranspiration, the simulated concentration at the base of the root zone ranged from about 5,200 to about 6200 mg/l, the discharge rate ranged from 2.3 to 1.9 mm/d. When the applied recharge concentration was changed to 1,000 mg/l and 700mg/l, but with all the other parametersmaintained, the simulated concentration at the base of the root zone ranged from 3,700 to 4,400 mg/l, and from 2,800 to 3200 mg/l for the different spacing, respectively.
  • Assessment of Helminth Infections in Goats Slaughtered in an Abattoir in a suburb of Accra, Ghana

    Futagbi, G.; Abankwa, J.K.; Agbale, P.S.; Aboagye, I.F. (Ecological Laboratory Unit, University of Ghana, 2016-02-15)
    A cross-sectional study to evaluate parasitic infections in small ruminants was conducted in an abattoir in a suburb of Accra from January to March 2015. Samples from various sections of the gut of 35 goats, either reared in Ghana or imported from Burkina Faso, were analyzed using the Kato-Katz technique. The overall prevalence was 100%. The proportions of goats infected with each parasite type were 100%, 94.4%, 88.6%,80.5%, 68.6 62.8% and 44.4% respectively for Strongyloides sp., tapeworms, Ascaris sp., Fasciola hepatica, Trichuris sp., Haemonchus contortus and Schistosoma haematobium. The proportion of animals infected with Haemonchus contortus was significantly higher in imported goats than those reared locally (p<0.05). The mean intensity of infection was low for all the parasites. However, high diversity of parasites with 80% of goats having at least four parasite types was observed. The data show high multiple infections in the goats brought to the slaughter house and suggest the need to institute appropriate measures to curb the problem.
  • Using Machine Learning for Land Suitability Classification

    Aminzadeh, F; Zarei, AR; Mokarram, M; Hamzeh, S (Ecological Laboratory Unit, University of Ghana, 2015-09-10)
    Artificial intelligence and machine learning methods can be used to automate the land suitability classification. Multiple Classifier System (MCS) or ensemble methods are rapidly growing and receiving a lot of attention and proved to be more accurate and robust than an excellent single classifier in many fields. In this study a dataset based land suitability classification is addressed. It is done using a newly proposed ensemble classifier generation technique referred to as RotBoost, which is constructed by combining Rotation Forest and AdaBoost, and it is known to be the first time that RotBoost has been applied for suitability classification. The experiments conducted with the study area, Shavur plain, lies in the northern of Khuzestan province, southwest of Iran. It should be noted that suitability classes for the input data were calculated according to FAO method. This provides positive evidence for the utility of machine learning methods in land suitability classification especially MCS methods. The results demonstrate that RotBoost can generate ensemble classifiers with significantly higher prediction accuracy than either Rotation Forest or AdaBoost, which is about 99% and 88.5%, using two different performance evaluation measures.
  • Characterization of Soil-Water Retention with Coarse Fragments in the Densu Basin of Ghana

    Yangyuoru, M; Boateng, E; MacCarthy, DS; Breuning-Madsen, H (Ecological Laboratory Unit, University of Ghana, 2013-09-30)
    The presence of coarse fragments can have profound impact on soil moisture retention characteristics. The study was conducted to assess the effects of coarse fragments on the moisture retention characteristics of 16 soil series, developed over five different parent materials in the Densu basin. Soil profiles were excavated at five locations, to depths within 1.5 m in the field. Undisturbed soil core samples and disturbed samples were taken in triplicates from the major genetic horizons of each soil type within the effective root depth of 1 m. Coarse fragments content of soil more than 2 mm was measured on mass basis by sieving through a 2-mm mesh. Soil moisture retention was determined using the pressure plate apparatus at suctions of pF 1 (1.0 kPa), pF 2 (10.0 kPa), pF 2.5 (33.0 kPa) and pF 3 (100.0 kPa) for the undisturbed and pF 4.2 (1500 kPa) for the disturbed samples.The volumetric moisture content between field capacity (FC) pF 2.5 (33.0 kPa) and permanent wilting pointing (PWP) pF 4.2 (1500.0 kPa) was used to evaluate the available water content (AWC) by volume and then converted to root zone available water capacity (RZAWC) in millimetres (mm) assuming an effective root depth of 1 m within the basin. Results showed that soils formed over granite and its associations have high percentage of coarse fragments while soils developed over phyllites and its associations have high clay percentage. Soil organic matter was high in the topsoil of all profiles, ranging from 0.81 to 4.44% compared with the horizons below, and the bulk density of the topsoils were less than the limiting value of 1.6 Mg m-3. Site-specific moisture retention characteristics of the various soil series have been delineated. It was evident from the analyses that soils containing high clay content gave high RZAWC values compared with soils with high coarse fragments. Most of the topsoils of the profiles gave high RZAWC values compared with sub-layers with high amounts of coarse fragments. Critical water for plants establishment within the basin in the surface layer was quite favourable.
  • Study of the Reproductive Characteristics of Nine Cassava Accessions

    Oduro, V; Asare, DK; Amoatey, HM; Klu, GYP; Nunekpeku, W; Danso, KE (Ecological Laboratory Unit, University of Ghana, 2013-09-30)
    Reproductive behaviour of two cultivars (AF and AN) and seven breeding lines (BA, AS, LA, BS-1, HO-008, ME and SE) of cassava (Manihot esculenta Crantz) was studied to obtain information pertaining to flowering habits and other reproductive characteristics of these potential parents required for future hybridization programmes. The accessions were grown on the Research Farm of the Biotechnology and Nuclear Agriculture Research Institute in the coastal savanna agro-ecological zone of Ghana between April 2008 and December 2009. For each accession, 40 stem cuttings, each bearing five to eight nodes, were prepared from the mid-section of healthy cassava stems and planted at a spacing of 1.5 m x 1.0 m while accessions were separated by a distance of 2 m. Ten plants were tagged per accession for the collection of data on key reproductive characteristics. All accessions flowered, suggesting that flower production may not be a limiting factor under the prevailing climatic conditions. Light microscopy revealed that one accession (BA) produced dysfunctional male flowers which were devoid of pollen. Mean days to flowering and fruiting varied significantly (P < 0.05) among the accessions, indicating the need to use different planting dates for different accessions to ensure synchronization of flowering. The accessions also differed significantly (P < 0.05) with respect to plant height at various levels of branching, as well as number of inflorescences, staminate and pistillate flowers, and fruit produced per branching level. There was also variation in percent seed set, embryo formation and fruit drop. The extensive variability observed among the accessions provides breeders with immense opportunities for carrying out cross combinations to generate new genotypes to meet specific objectives.
  • Biodiversity Change: Preliminary Monitoring of Anura Species in Selected Vegetation Sites in Southwestern Nigeria

    Saliu, JK; Onadeko, AB; Egonmwan, RI (Ecological Laboratory Unit, University of Ghana, 2013-09-30)
    Four study sites with different vegetation structures in southwest Nigeria were selected and monitored for anuran species between 2007–2009 applying the transect sampling method. These study sites were located at Ijede (06º 34’ 072’’ N 003º 35’ 030’’ E), Ijebu Oru (06º 56’ 493’’N 003º 56’ 792’’E), Onidundun (07º 37’ 313’’ N 003º 55’ 258’’ E) and Ibapon Oyewole (08º 05’ 129’’ N 004º 11’ 132’’ E), all in southwest Nigeria. The study sites of Ijebu Oru (forests/abandoned farmlands) and Ibapon Oyewole (savanna) had a mean number of species and individuals of 21 and 14, and 236 ± 5 and 108 ± 7.9, respectively. However, at Ijede (swamps/forests), there was 18% reduction (6% in 2008; 12% in 2009) of the initial number of species recorded in 2007 due to shifting agricultural practices. Hylarana albolabris, Aubria subsigillata and Ptychadena aequiplicata were no longer accounted for in 2009 surveys. At Onidundun (derived savanna/forests), there was a 17% reduction of anuran species (Ptychadena mascareniensis, Hyperolius f. burtoni and Arthroleptis sp.) in 2008, but 12% of these species (Hyperolius f. burtoni and Ptychadena mascareniensis) were again seen in 2009 after substantial amount of vegetation growth had occurred. The mean number of species and individuals at the study sites of Ijede and Onidundun were 16.67 ± 1.5 and 16.67 ± 1.5; and 203.67 ± 6.7 and 169.67 ± 8.3, respectively. In general, fewer number of amphibian species were observed during the dry season at the four study sites. Habitat destruction and modification are key causes of habitat loss of anuran species observed in this study. Biomonitoring procedures should be applied regularly to detect changes (increase/decrease) in the diversity and abundance of anuran species within a specified study area of interest over time.
  • The Use of Rock Phosphate and Phosphate Solubilising Fungi (Aspergillus niger) to Improve the Growth and the Yield of Upland Rice on Typic Kandiudalf

    Asuming-Brempong, S; Anipa, B (Ecological Laboratory Unit, University of Ghana, 2014-09-19)
    Field experiment was conducted to study the effect of rock phosphate (RP) and phosphate solubilizing fungi application on upland rice yield  intercropped with pigeon pea from 2009 to 2011 at the Agricultural  Research Centre, Kade, University of Ghana. In the first year, the main plot treatment consisted of five levels of phosphate fertilizer viz. 0 kg/ha P2O5, 40 kg/ha P2O5 RP, 80 kg/ha P2O5 RP, 120 kg/ha P2O5 RP and 45 kg/ha P2O5-triple super phosphate (TSP), while the planting dates of pigeon pea was set up as subplot (40 DAS –pigeon pea planted 40 days after sowing rice seed and 80 DAS- pigeon pea planted 80 days after sowing rice). In the second year, phosphate fertilizer was the main plot treatment,  consisting of (0 kg/ha P2O5, 45 kg/ha P2O5 RP, 90 kg/ha P2O5 RP and 45 kg/ha P2O5 TSP), and the subplot treatment was inoculated and uninoculated with phosphate solubilising fungi Aspergillus niger. The highest grain yield of 1.051 t/ha was obtained with the 120 kg P2O5 /ha RP followed by the 40 kg P2O5 /ha RP. Phosphate levels did not  significantly influence the grain yield in the first year (p = 0.08) but planting pigeon pea as an intercrop at the different planting dates had a significant positive effect on both the grain and straw yields of rice (p = 0.016, .07). There was no significant interaction between the use of different phosphorus levels and the different planting dates of pigeon pea (p = 0.348). In the second year, phosphate levels had significant influence on grain yield (p = 0.014) and the highest grain and straw yields occurred where TSP and Aspergillus niger were used to plant rice. Inoculating rice with or without Aspergillus niger had no significant influence on grain yields (p = 0.447). No significant interaction existed between phosphate levels and level of inoculation (p = 0.206). The use of TSP and Aspergillus niger to grow rice improved rice yield followed by 45 kg P2O5/ha RP + Inoculation.
  • Improving Moringa Growth by Using Autochthonous and Allochthonous Arbuscular Mycorrhizal Fungi in Lake Victoria Basin

    Knopf, E; Munch, JC; Blaschke, H (Ecological Laboratory Unit, University of Ghana, 2013-09-30)
    Biological methods such as mycorrhiza biotechnology used for raising and sustaining soil fertility in agricultural ecosystems close to freshwater biomes are gaining attention. However, ubiquitous ecological conditions may subject mycorrhizal management to choices that depend on inoculum sources (autochthonous or cultured). Effects of AMF on growth of M. stenopetala and M. oleifera were evaluated using three native soil types, representative of Lake Victoria basin and a standard substrate. Autochthonous AMF was harnessed from the native soils while allochthonous AMF cocktail was acquired from culture banks of Glomus hoi, G. mosseae and G. intraradices, using Plantago major as plant indicator and trap-culture. The soils were blocked according to tillage intensities. P. major supplied Moringa with AMF inoculum. To facilitate mycorrhization, nitrogen fixing bacteria (NFB) in chickpea rhizobia inoculum was integrated. The hyphopodium assays revealed > 90% arbuscle occupancy in root cortex of plants established in paddy LT soils. AMF inoculation improved growth and biomass of both Moringa species. Autochthonous AMF inoculum had relatively higher biomass turnover compared to cultured AMF. The presence of dark septate endophytes (DSE) in plant biodiversity gave a new insight into target plant performance at plant competition for nutrients. Results reveal that inoculum AMF and NFB are potential candidates in optimizing plant production technology applicable in eco-sensitive-oriented low in-put agriculture.
  • Impact of Urban Effluents on the Macroinvertebrates of a Creek in Accra, Ghana

    Asante, F; Baa-Poku, J; Amakye, JS (Ecological Laboratory Unit, University of Ghana, 2013-09-30)
    The impact of effluents on the macroinvertebrate communities of an urban creek in Accra was studied. Five study stations were selected along the reaches of the creek. Water and benthic samples were collected and analyzed between September 2005 and February 2006. The study showed that the effluent discharges caused a significant increase in BOD, COD and NH3 at the stations that received the effluents. The high levels of total and faecal coliforms at the midstream sections of the creek (626.0 x 104 cfu/100 ml and 75.30 x 104 cfu/100 ml, respectively) indicated increased pollution levels compared to the reference stations (446.0 x 103 cfu/100 ml and 133.0 x 103 cfu/100 ml). The Nima Creek showed characteristics of a disturbed urban creek. A total of 19 macroinvertebrate taxa, comprising a total of 11,613 individuals, were collected. Estimated Shannon-Weiner Diversity Index (H´) was low at the midstream section of the creek, H’= 1.14, where the effluents were concentrated than at the upstream H’=1.44 or downstream H’= 1.38 sections of the creek. Chironomini and Physa were the most abundant taxa within the creek, dominated by the genus Chironomus, which is known to be tolerant to pollution, which confirmed the polluted state of the creek. Rigorous and regular assessment and monitoring of effluents from waste treatment plants and other sources that discharge into the creek, with the aim of complying with the Environmental Protection Agency (EPA) guidelines are some of the mitigative measures suggested to protect life in the creek.
  • Evaluation of an Integrated Approach Involving Chemical and Biological Processes for the Detoxification of Gold Tailings Effluent in Ghana

    Ahmed, RM; Osei, BA (Ecological Laboratory Unit, University of Ghana, 2013-09-30)
    Chemical and bio-remediation measures for the detoxification of pollutants such as cyanide and heavy metals in mine tailings effluent have been developed over the years. The study sought to evaluate the decrease in the concentrations of Cu, Zn, Fe, Cd, As and Pb through the integration of the processes involving photo-oxidation, activated carbon, hydrogen peroxide and bacterial degradation to decontaminate wastewater from the gold ore treatment plant until release into the environment in Ghana. The levels of trace metals Cu (0.345 mg l-1), Zn (0.07 mg l-1) and Fe (0.146 mg l-1) in treated effluent released into natural water bodies after bacterial degradation was generally within international and local standards for effluent discharges. Except for As, the levels of Cd and Pb which are hazardous heavy metals that may pose adverse health and environmental effects were within acceptable limits. The toxicity of these metals were in the increasing order Pb < Cd < As. The anthropogenic source of As in the chemically processed arseno-pyritic rock ores of the study area and the marginal 14–49% efficiency of As of the different detoxification processes could have contributed to the high levels of As in the effluent. If optimal conditions are attained for the decontamination processes used, the multi-remediation approach could be an effective solution for the decontamination of mine tailings effluent.
  • Effects of Chromolaena and Tithonia Mulches on Soil Properties, Leaf Nutrient Composition, Growth and Yam Yield

    Adekiya, AO; Agbede, TM; Ogeh, JS (Ecological Laboratory Unit, University of Ghana, 2013-09-30)
    Plant materials differ in their chemical composition, rate of decomposition and suitability as mulch materials. Experiments were conducted on an Oxic Tropuldalf of southwestern Nigeria at Owo to study the effect of Chromolaena and Tithonia mulches applied at 0.0, 5.0, 7.5, 10.0 and 12.5 t ha-1 on soil chemical properties, leaf nutrient composition, growth and tuber yield of white yam (Dioscorea rotundata Poir). Both Chromolaena and Tithonia mulches reduced soil bulk density and temperature. They also increased concentrations of organic matter, N, P, K, Ca and Mg in the soil, and N, P, K, Ca and Mg in the leaves. The mulches also increased growth and yield of yam compared with the control. The values of soil organic matter, N and P, and leaf N and P concentrations increased with increasing mulch rate. Chromolaena mulch and Tithonia mulch applied at 10.0 and 7.5 t ha-1, respectively, were found to be suitable for yam production. Tithonia mulch compared with Chromolaena mulch produced higher values of soil chemical properties, leaf nutrient concentrations, growth and yield of yam. Tithonia mulch produced 19% and 18% higher tuber yield compared with Chromolaena mulch in the first and second cropping seasons, respectively.

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