Porosity variabilities along a forest – grassland mosaic in Ibeku, Abia State, Nigeria

Variation existed in the porosity characteristics of pedons located on forestland and grassland. Percent coefficient of variation (CV) was greater in forest soils for both bulk density and porosity (% CV = 29.99 and 13.2) than as found in grassland soils (% CV = 2.6 and. 4.1). These results were explained by wide variations in percent organic matter content existing between the two groups of pedons. While percent coefficient of variation for forest soil was 130.1 that of grassland gave 61.4. Keywords: bulk density porosity, variability, vegetation International Journal of Natural and Applied Sciences Vol. 1(1) 2005: 1-

Soil colors as indicators of soil quality in soils formed over coastal plain sands of Owerri agricultural area, southeastern Nigeria

The study investigated soil chemical properties associated with three different soil colors, namely Dark reddish brown (5YR3/2) moist, Reddish brown (5YR4/4) moist and Light reddish brown (5YR) moist. Dark reddish brown soils were slightly acidic (pH 6.1) while reddish brown and light reddish brown colors were moderately acidic (pH = 5.0) and strongly acidic (pH= 4.5) respectively. Effective cation exchange capacity (ECEC) was highest in dark reddish brown soils (7.2 cmol/kg), followed by reddish brown soils (6.2 cmol/kg), while 5.5 cmol/kg was recorded on light reddish brown soils. Value of total carbon was highest in dark reddish brown (2.0%), while reddish brown and light reddish brown soils had 1.2 and 0.7% respectively. Soil pH varied with color with dark reddish brown giving a coefficient of variation (CV) of 10%, reddish brown, CV of 31% and light reddish brown CV of 55%. Variability was indicated in total carbon with dark reddish brown having CV = 40%, reddish brown CV = 24% and light reddish brown CV = 12%. Soil color could be used as reliable indicator of soil quality in the tropical humid rainforest area of Owerri, Southeastern Nigeria. International Journal of Natural and Applied Sciences Vol. 1(2) 2005: 118-12

Effect of crude oil pollution on maize growth and soil properties in Ihiagwa, Imo State, Nigeria

The influence of crude oil on maize growth and soil properties were evaluated in an Ultisol in Ihiagwa, Imo State, Nigeria. Four kg of air-dried soil samples were weighed into 4.5 litre plastic pots and treatment consisting of 6 levels of crude oil (0, 1, 2, 3, 4, and 5 t/ha) applied. Ten healthy maize seeds (Variety: Farz 27) were sown and the pots arranged in a completely randomized block design. Field trial was also conducted and three maize seeds (var. Farz 27) which were later thinned down to one plant per stand after germination were planted on plots measuring 4 x 4 m2. Crude oil treatments were applied at rates as used for the potted experiment, at three weeks after planting (WAP). The experimental design was a randomised complete block design with 3 replications. The experiment lasted for 12 weeks during which time, plant height and leaf area was estimated at a weekly interval. Plant mortality and dry matter yield were determined at the end of the 12 weeks growth period. Soil assays were run at beginning and end of study. Seed germination, plant height, leaf area and dry matter yield significantly decreased as the level of crude oil pollution increased. As crude oil pollution levels increased, soil pH also increased. There was no remarkable change in the level of soil organic carbon, nitrogen, exchangeable bases, exchangeable acidity, available phosphorus and effective cation exchange capacity as crude oil pollution increased in both studies. The primary way in which crude oil pollution reduces crop growth and performance would appear to be through reduction of seedling emergence and direct suffocation of plant roots by changing the redox potential and oxygen diffusion rates between soil system and the atmosphere.Keywords: crude oil, maize, soil property, pollutionInternational Journal of Agriculture and Rural Development Vol. 5 2004: 91-10

Effect of Palm Oil Milling Wastes on the Physico-Chemical Properties of Soils in Okija, Southeastern Nigeria

This research work was carried out to determine the physico-chemical properties of soils as affected by palm oil milling wastes in Okija, Anambra state, Nigeria. Soil samples from an abandoned palm oil mill (site 1), active palm oil mill (site 2) and a fallow land (site 3) were collected from three mini-pits per land unit at 0-20 and 20-40 cm depths. The soil samples were air-dried, sieved with a 2-mm sieve and analyzed for physico-chemical properties. Data collected in a Randomized Complete Block Design (RCBD) were subjected to analysis of variance. ECEC were significantly different (p<0.05) in the surface and subsurface soils among the sites. Significant differences also existed among bulk density of the surface soils. Again, significant difference existed in the Ca2+ content of the surface and subsurface soils among the sites. The Ca2+ content of the soils of abandoned palm oil mill (13.98 Cmolkg-1) was about 50% more than that of soils of the other two study sites. Available phosphorous in the study sites was highly variable (CV = 71 %) and the values were significantly different in the surface and subsurface soils among the sites. There were significant differences in the organic matter contents among the surface soils of the study sites and were highly variable (CV= 53%). It is therefore advisable that palm oil mill wastes especially palm oil mill effluent undergoes some form of treatment or decomposition before deposition on the soil.Keywords: Palm oil milling effluent, soil properties, fertility indices, target soil survey, mini-pits

Iron distribution on a chronosequence located at Imo River floodplain, South Eastern Nigeria

The study was conducted on soils of a floodplain to investigate the occurrence and distribution of iron (Fe) and relating it to soil properties. Silt-sized particles dominated in the backswamp (2—6%) unlike other locations on the floodplain (2—3%) soil pH was distributed as follows: 4.2-4.6 (Backswamp), 4.1-4.5 (Levce) and 3.6-4.1 (Terrace). Crystalline iron (Fedi) dominated over amorphous iron (Feox), having 15.83g/kg and 4.46g/kg respectively. The Feox: Fedi ratio 0.2 suggested the predominance of Lepidocrite, goethite and haematite in the backswamp. We also postulated that soil pH could be used to predict availability of Fe forms based result of correlation (r = 0.78 -0.82, p=0.05, n =15) and coefficient of determination (r2 = 0.61 - 0.70, p = 0.05 n =15). International Journal of Agriculture and Rural Development Vol. 7(1) 2006: 99-10

Management of Podrot, Oil Content, and Pod Weight of Benniseed in an Ultisols

Benniseed (Sesanum indicum L) is a well known oilÐseed crop grown mostly in the Savannah areas of Nigeria, and with little cultivation in the forest south. A two-season experiment was conducted in 1997 and 1998 to determine the effect of plant population and nitrogen application on podrot, oil content and pod weight of benniseed in the rain forest belt of Nigerian. Analysis of variance indicated that only the podrot and oil content were affected by plant population. An increase of 15.6% and 16.2% in oil content was recorded when plant population increase from 111,111, to 250,000 plants/ ha recorded list podrot 2.02; 2.30 in 1st and 2nd seasons while 60kg/ha recorded lowest podrot 2.59; 2.63 in 1997 and 1998, respectively. The 0kg/ha (control) recorded highest podrot 3.14; 3.46 in 1997 and 1998, respectively. An increase of 15.6% and 16.2% oil company was recorded when plant population increased from 111,111 to 250,000 plants/ha in the 1st and 2nd seasons, respectively. Further increase from 62,500 to 111,111 resulted to further increase of 4.6 and 5.2 in the 1st and 2nd seasons, respectively. The 9kg is highly significant on podrot (

Effects of tillage operations and plant density on leaf spot disease severity and grain yield of maize in ultisols

Two seasons experiments conducted in 2002 and 2003 revealed that Tillage operations significantly influenced leafspot disease severity; Percentage lodging 3.14; 2.08 and Grain yield 3.02; 3.84 in 2002 and 2003 respectively. Plant density also had significant difference on leafspot disease severity; Percentage lodging 4.82, 3.16 and Grain yield 4.00; 4.18 in 2002 and 2003 respectively. Spot tillage recorded low leafspot disease severity 0.94; 1.02 in comparison with Strip tillage 1.18; 1.30 when zero tillage (control) 2.28; 2.77 were high. 53,000 plants/ha recorded high leafspot disease severity 1.84, 1.95 in comparison with 26,666 plants/ha 1.05, 1.14 when 17,777 plants/ha 0.92; 1.00 were low in 2002 and 2003 respectively. Spot tillage recorded significantly highest grain yield 4.35; 4.72 tons/ha followed by strip 3.82; 4.02; when zero tillage 3.20; 3.66 were lowest. 53,000 plants/ha recorded high grain yield 4.51; 4.30 tons/ha in comparison with 26,666 plants/ha 2.48; 1.10 when 17,777 plants/ha 2.02; 1.95 were low in 2002 and 2003 respectively. International Journal of Agriculture and Rural Development Vol. 7(1) 2006: 33-3

Seasonal Dynamics of Soil Organic Matter and Total Nitrogen in soils under different land uses in Owerri Southeastern Nigeria

The study investigated seasonal dynamics of soil organic matter and total nitrogen in soils affected by different land use types in Owerri, Southeastern Nigeria. A total of 72 soil samples were randomly collected at two monthly intervals in the dry season (October/November, December/January and February/March) and rainy season (April/May, June/July and August/September) at 0-20 cm depth in all the studied land uses, namely soils under continuous cassava cultivation (CCS), pineapple orchard soil (POS), bush fallow (FS) and bare fallow (BF.) . Collected soil samples were air dried, passed through 2mm sieve and were analysed using standard methods. The experiment was factorially arranged in randomized complete block design (RCBD), with three factors namely, season, month and landuse. The treatments were replicated three times. Generated soil data were analysed using analysis of variance (ANOVA) and significant means were separated using least significant difference (LSD) at 5% probability. Results showed that soil organic matter and total nitrogen were significantly higher (P<0.05) in the dry season especially between January and April compared to the rainy season where the least was found around June/July in all the studied land uses, although in all cases, their variability was minimal, ranging from 30.49% in (CCS) to 47.68% in bare fallow. Significant positive correlation (P < 0.05) was found between soil organic matter (SOM) and total nitrogen (r2= 0.966 CCS; 0.935 FS, 0.626 POS, and 0.796 BF), and negative correlation with CN ratio (r2=0.917 CCS; 0.729 FS, 0.3 POS; 0.347 BF), respectively, bulk density (r2 = 0.63) only in FS. Similarly significant negative correlations (P< 0.05) were also found between TN and CN ratio (r2 =0.865 CCS, 0.716 FS, 0.796 POS and 0.328 BF).Keywords. Tropical soil, seasonal variability, total nitrogen, organic matter, land use, Southeasthern Nigeria

Soil physical criteria for evaluating irrigation suitability of Okija upland soil of southeastern Nigeria

Suitability of upland soils of Anigbo Okija for irrigation was assessed using soil physical criteria of texture, depth, pore type, slope percent colour and soil structure for the purpose of estimating season farming and rainy season drought. Soils were classified using Soil Taxonomy and FAO/UNESCO legend. Mapping was done based on physiographic differences. Results showed two distinct soil mapping units A1 and A2 with two suitability classes: moderately suitable (S2) and marginally suitable (S3)., based on soil erosion and topographic limitations respectively. Two capability classes were consequently identified as e and IIIe for soil mapping units A1 and A2 respectively. Soils were classified as Typic Paleudalf and correlated to FAO/UNESCO legend as Dystric Nitisol for soil mapping unit A1 and Typic Paleudult (S.T.) or Dystric Nitisol (FAO/UNESCO legend) for A2. Journal of Agriculture, Forestry and the Social Sciences Vol. 3 (2) 2005: pp.99-10

Enhancing Jatropha curcas (Linnaeus) Cultivation and Seed Yield among Farmers in Nigeria: A Review

Jatropha curcas yields substantial quantity of seed oil and is growing in importance as a source of biodiesel. In Nigeria, the plant has traditionally been grown as live fences and hedge plants around homesteads and gardens to screen off unwanted sites or protect crops against roaming animals. Traditionally, growers are not so much concerned with selection, production, dissemination, and access to improved seeds. With increasing interest in renewable energy around the world, it has become necessary for breeders to, in the first instance, identify and characterize the available germplasm in Nigeria. Subsequently, there is need for appropriate production practices relative to the different ecological zones in order to greatly expand cultivation. During studies at the Federal University of Technology, Owerri in Nigeria, no major pests and diseases were observed. While 90 % of the seeds emerged at not more than 6 days after planting, 40 % of the seeds raised without shade emerged at 4 days after planting whereas only 20 % of those raised under shade emerged at the same time. Seed treatment resulted in less than 30% emergence and treated seeds that emerged were stunted and had scotched leaves. Multiplication by cuttings was generally faster than by seed although lodging was a problem. Cuttings measuring 60 and 90 cm performed better compared with 30 and 120 cm cuttings. Cuttings made from the semi-hard wood part of the stem produced shoots and rooted faster than those obtained from the apical and the basal points.Keywords: Jatropha curcas, cuttings, seed oil, biofuel, emergence, shading, breeding