Evaluation of Hydraulic Conductivity of Non Aqueous Phase Liquids in Partially Saturated Soils

This study seeks to investigate a problem of predicting the hydraulic conductivity of NAPLs in partially saturated soils and to relate the hydraulic conductivity to basic soil parameters that are either easy to determine or are in wide use. To evaluate hydraulic conductivity in partially saturated soils, previous researchers have focused on flow geometry, soil and chemical properties, etc. used in CHEMFLO program by Nofziger et al., (1989) and saturation equations by such authors as Van Genutchen (1980) and Brooks and Corey (1964). Among those, the soil-water characteristic curve (SWCC) is the most widely used constitutive relations for unsaturated soils (Claudia, et al. 2000). It uses matric suction to relate to fluid flow characteristics of unsaturated soils. However, the authors concluded that even the most experienced researchers have difficulties in getting a unique SWCC for a soil and that soil suction and SWCCs cannot be simply measured with great precision at the present time. Hillel (1998) stated that there is as yet no universally accepted method available to predict unsaturated hydraulic conductivity from more easily obtainable soil properties

Simulating planting date and cultivar effects on dryland maize production using CERESmaize model

Open Access JournalMaize farmers and extension agents in dry sudan savanna need information on how planting date and the choice of variety affect grain yield. This study was conducted to test the ability of model to predict maize yields under varying planting dates. Data on two open-pollinated maize cultivars (TSB-SR and TZE-COMP4) sown on different dates (June 29th, July 13th, July 21st and July 28th) in 2006 and 2007 at Azir (11° 01.820´ N, 12°37.714´ E; 441 m) and Damboa (11° 10.379´; 12° 47.145´E; 396 m) in the Sudan Savanna of Nigeria were used in running the model. Experimental data from Azir in 2006 was used to calibrate the model, while the data for 2007 at Azir 2006 and 2007 at Damboa were used for model validation. The model predicted days to anthesis at Damboa as reasonably well in both 2006 and 2007 (d-index >0.8), while at Azir, the prediction of days to anthesis was very poor in 2007. The match between predicted and observed grain yield were very good in 2007 at both locations. The root mean square error (RMSE) values for grain yield in 2007 were 431.5 and 226.5 kg ha-1 at Azir, and 799.5 and 611.5 kg ha-1 at Damboa for TZB SR and TZE COMP4, respectively, while the d-index values were all greater than 0.94. Generally, the model predicted decrease in grain yield with delay in planting date except for TZB-SR at Azir in 2006 where planting on July 13th gave higher yield than planting on June 29th. The grain yield values from the simulations suggested late June to early July as the optimum planting window for both varieties at both Azir and Damboa

Microbial Quality of Commercially Packed Fruit Juices in South-East Nigeria

The microbiological quality of commercially packed fruit juices sold in South-East Nigeria were assessed. A total of forty (40) juice samples consisting of orange, apple, pineapple, lemon, and guava flavoured varieties were collected. Samples were screened for total viable count, total coliform count, faecal coliform count, total staphylococcal count and total fungal count using standard microbiological methods. The highest total bacteria load of 4.4×105 cfu/ml was observed in sample A (Orange) while the lowest was observed in sample D of Apple variety (1.95×104 cfu/ml). The total coliform count ranged from no count in samples A, B, C and D to 9.8×101 cfu/ml in sample I (Guava juice). In all the samples, there was no faecal coliform found. The staphylococcal count ranged from no count in samples E, F, I and J to 8.4×102 cfu/ml in sample G (lemon juice). The highest total fungal count of 1.6×105 cfu/ml was observed in sample I (Guava) and the lowest count was observed to be 1.2×103 cfu/ml in an apple juice (sample D). The microorganisms isolated from the samples included Staphylococcus aureus, Bacillus species, Enterobacter species, Acetobacter species, Lactobacillus species, Saccharomyces cerevisiae, Aspergillus species, Rhizopus species and Penicillium species. Bacillus species was the most common (70%), followed by S. aureus (60%), Enterobacter spp., Lactobacillus spp. and Saccharomyces cerevisiae had the same rate of 50% respectively, and Acetobacter spp. and Penicillium spp. had the same rate of 40% while the least occurrence was seen in Aspergillus spp. and Rhizopus spp. with the rate of 30% respectively. The result showed that different bacterial and fungal species occurred within the fruits juices. The materials used for the production of the juice, poor sanitation, extraction, raw material contamination, lack of both proper heat sterilization and adequate quality control during processing of fruit juice could be a contributory factor to the presence of these organisms in the fruit juices. Some of the fungal isolates especially Penicillium sp. and Aspergillus sp. could result in the production of mycotoxins, which could lead to health hazards for the consumer and their presence in the fruit juices is of public health significance. Therefore, regular monitoring of the quality of commercially available fruit juices for human consumption is recommended to avoid outbreak of food borne illness resulting from the organisms encountered in this study

Comparative Studies of the Clarification Potentials of Ferric Chloride and Moringa Oleifera Coagulants

The significant treatment costs of drinking water make treated water costly, raising the price of clean and helping make clean water inaccessible to the poor people in rural communities. This compels them to turn to readily available sources which are mainly contaminated. This subjects them to waterborne diseases.In this context, this study was carried out to validate the efficiency and, if feasible, the substitution of Ferric Chloride utilised in the treatment of water using Moringa Oleiferaseeds, a cheap and widely accessible indigenous coagulant. The quality of water was tested on collection compared to those treated with Ferric Chloride and Moringa Seeds. Doses of 5 g, 10 g, 15 g, 20 g, 25 g and 30 g of both coagulants were used to treat 500 ml of water. Control water without Ferric Chloride and Moringa treatments was included. The pH, turbidity, conductivity and COD were measured. From the ANOVA statistical analysis, several factors such as pH were analysed, and there was a wide variation between the two treatments of Moringa and Ferric Chloride.

EGGPLANT (Solanum sp) PERFORMANCE IN ORGANIC AND INORGANIC SYSTEMS IN SOUTH-EASTERN NIGERIA

The problem of rural-urban migration in Nigeria has resulted in very dense urban populations. The location of poultry and aquaculture enterprises in urban and peri-urban areas of the country has exacerbated the problem of pollution. However, these wastes can be a valuable resource for use in agriculture, thereby offering a solution to pollution arising from intensive peri-urban aquaculture, thereby offering a solution to pollution arising from intensive peri-urban aquaculture and poultry enterprises. The aim of this study was to examine the effects of fibre glass fish tank effluent,poultry manure, NPK and control on two eggplant varieties and weeds. The response of eggplant fruit yield to poultry manure was significant and greater than the response to fish effluent, which also gave higher yield than NPK fertilizer or control. The fruit yield obtained from poultry manure was higher than the yield from fish effluent, NPK and control by 61%, 177% and 148%, respectively. Fish effluent gave fruit yield that was higher than that from NPK by 72% and control by 55%. Kaduna variety produced yield that was superior by 71% and had lower weed density compared to Ngwa loca

Evaluation of Micro-Pathogens Associated with Nigerian Currency (Naira Notes)

Evaluation of micro-pathogens associated with the Nigerian Currency (Naira note) was examined using the standard microbiological techniques. The bacterial load of the Naira notes ranged from 4.0±0.6x103 cfu/ml to 50.0±0.1x103 cfu/ml which differed significantly (p<0.05) when compared with the control sample which had no bacterial growth. The fungal count of the Naira notes ranged from 3.0±0.9x103 cfu/ml to 23.0±0.1x103 cfu/ml. The following microbial species were isolated with a varying prevalence; Bacillus species 41 (10.3%), Klebsiella species 37 (9.3%), Proteus species 29 (7.3%), Corynebacterium species 28 (7.0%), Staphylococcus epidermidis 24 (6.08%), Staphylococcus saprophyticus 44 (11.0%), Staphylococcus aureus 31 (7.8%), Clostridium species 18 (4.5%), Micrococcus species 16 (4.0%), Escherichiacoli 15 (3.8%), Fusarium species 15 (3.8%), Penicillium species 13 (3.3%), Aspergillusfumigatus 12 (3.0%), Aspergillus flavus 11 (2.8%), Rhizopus species 5 (1.3%), Aspergillus niger 31 (7.8%) and Mucors species 29 (7.3%). The different denominations of the Naira note showed that 20 Naira recorded the highest microbial isolate of 81(20.3%), followed by 10 Naira note 70(17.5%) while the least was 1000 Naira note 18(4.5%). The different denominations of the Naira note showed that 20 Naira had the highest occurrence of bacteria (58) and fungal occurrence of 23, the least was 1000 Naira which recorded the occurrence of 13 and 5 for bacteria and fungi, respectively. The study showed that Naira notes are commonly contaminated with pathogenic microorganisms of public health importance. Therefore, the Nigerian currency (Naira note) should be handled with care so that it will not be a vehicle for disease transmission

Weed seedbank response to planted fallow and tillage in southwest Nigeria

Planted fallows are an alternative to the unsustainable bush fallow for improved soil and weed management in the tropics. However, the interactive effects of planted fallows and tillage on the weed seedbank are not well documented in the tropical environment. The effect of fallow type and tillage on the weed seedbank in the soil was assessed in 1995 and 1996 at Ibadan, southwest Nigeria. The planted fallow species consisted of a herbaceous legume (Pueraria phaseoloides) and three woody legumes (Acacia auriculiformis, Leucaena leucocephala, and Senna siamea). Natural bush fallow and continuous cassava/maize plots were controls. Tillage treatments were minimum tillage and mounding. Continuous maize/cassava plots had the largest weed seedbank in both years. After six years of continuous fallow, the weed seedbank was 86% lower in A. auriculiformis, 79% in P. phaseoloides, 68% in S. siamea, 53% in L. leucocephala, and 35% in natural bush fallow plots than in continuously cultivated plots. Compared to minimum tillage, mounding reduced the seedbank by 47% in 1995 and 66% in 1996. Redundancy analysis showed that tillage contributed significantly to the variance in species composition. Euphorbia hyssopifolia, E. heterophylla, and Cynodon dactylon showed no preference in terms of tillage. Perennial and annual grasses (Digitaria horizontalis, Eleusine indica, Paspalum orbiculare, Cynodon dactylon) with Cyathula prostrata and Desmodium scorpiurus, an annual and perennial broadleaf, respectively, were most abundant in the seedbank of continuously cultivated plots. There were more annual broadleaf weeds in the seedbank of planted fallow plots than in the control plots. Species diversity of the seedbank was greatest in plots under minimum tillage. Mounding as a seedbed preparation method, especially within the improved fallow system, could reduce the high weed pressure experienced by smallholder farmers in southwest Nigeria