Creating a soil data base in a reconnaissance soil fertility study of an encroached forest reserve in Northern Nigeria for a reforestation programme

The reconnaissance soil fertility study of 10,000 ha partly encroached forest reserve located between latitude 11°47’N and 11°56’N and longitude 4°22’E and 4°32’E in Northern Nigeria was conducted in 2009 to generate a soil fertility data base of the reserve. The tracking of the forest reserve boundary was done using a Garmin 72 model global positioning system (GPS) receiver. The geographic coordinates were input into the computer to generate a digital map of the forest reserve. The entire forest reserve was divided into grids to guide in the location for soil sampling using the GPS/Geographic Information System (GIS) geospatial technique. Soil auger studies were made at 250 locations to site 60 sampling pits to collect soil samples for laboratory analysis of soil properties. Forest soils were classified into three groups using soil depth as a limiting parameter in the soil fertility assessment. The soils were sandy clay loam and the pH indicated a moderate to strong acid status with low content of organic matter, percentage nitrogen, available phosphorus, potassium, calcium and magnesium. A reforestation programme with the planting of acacia for soil rehabilitation was recommended for the reserve as the tree stands would serve to protect the land against erosive activity of wind and also serve in enriching the soil with nitrogen.Key words: Soil fertility assessment, reforestation program, forest reserve, geographic information system

A precision nutrient variability study of an experimental plot in Mukono Agricultural Research and Development Institute, Mukono, Uganda

The spatial soil fertility status of a 2.5 ha experimental plot was generated by mapping the soil nutrient concentration and fertility status using GIS kriging technique. The research was conducted in Mukono Zonal Agricultural Research and Development Institute, Mukono, Uganda in October 2013. Soil samples across the experimental plot were randomly taken for laboratory analysis of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg) and the organic matter content. The mean values of N, P, K, Ca, Mg and the organic matter content were 0.16%, 13.7 ppm, 0.44 cmol/kg, 5.35 cmol/kg, 4.83 cmol/kg and 2.78% respectively. The spatial concentration of each element and the organic matter was carried out by the interpolation technique using the 3D Analyst/Raster Interpolation/Kriging Tools while the overlay operations to generate the soil fertility map was carried out using the 3D Analyst/Raster Math Tools in ArcMap. The autocorrelation analysis was carried out using the Spatial Statistics/Spatial Autocorrelation Tools. The autocorrelation analysis indicated N, Ca, Mg and organic matter to be somewhat clustered each with the Moran’s 1 Index of 0.37, P was clustered with Moran’s 1 Index of 0.5while potassium pattern was neither clustered nor dispersed. The spatial soil fertility pattern reflected the distribution of nutrient concentration.Key words: Nutrient variability mapping, Kriging technique, fertility mapping

Application of geographic information systems(GIS) in mapping soils of Owena forest reserve, Southwest Nigeria

No Abstract.Nigerian Journal of Soil Sciences Vol. 16 (1) 2006: pp. 35-4

Comparative effects of organic compost and NPK fertilizer on soil fertility, yield and quality of amaranth in southwest Nigeria

The need for an increased production of vegetables to meet the dietary vitamin requirements of the people had necessitated a research in the use of manure in improving the soil fertility for an improved yield andquality of amaranth. The research was conducted in Obasoto Farm (latitude 7°10’N and longitude 5°37’E) in Owo Local Government Area of Ondo State, Nigeria in the early and late seasons of 2007, 2008 and 2009. Theexperimental design was a randomized complete block with three treatments replicated three times. The three treatments were 0 kg/ha manure, 2t/ha organic compost and 200 kg/ha NPK 15-15-15. Amaranthus cruentus seeds obtained from the Ondo State Agricultural Development Project were raised in the nursery and transplanted at a spacing of 10 x 20 cm into 1 x 3 meter manually prepared beds. Each manure type wasincorporated by ploughing it in while preparing the bed at 600 g organic compost and 60 g NPK 15-15-15 fertilizer per the 1 x 3 meter bed respectively. Pre-treatment and post planting soil samples were taken forlaboratory soil analysis of soil chemical properties for a comparison of the assessment of the cumulative effects of organic compost and inorganic fertilizer in improving soil fertility over a period of three years. The organicmatter increased by 23.3% and 0.6% in the second and third year respectively in the plot treated with organic compost, while there was no such increase trend in the plot treated with 200 kg NPK/ha. The organic matter content correlated positively with the yield and vitamin C content of amaranth

Comparative effects of mechanized and manual tillage practices on soil properties and the yield of seed yam in Southwest Nigeria

The effects of various tillage systems on soil physical and chemical properties and the yield of seed yam were investigated and compared in a research conducted in Akure (Latitude 7o18’N and Longitude 5o15’E)-Nigeria in 2008 and 2009. Three tillage systems comprising ploughing plus harrowing, ploughing plus harrowing plus ridging and manual ridging were replicated three times in a randomized complete block experimental design. Healthy yam tubers weighing about 1 kg were cut into minisetts of about 25 g, treated with a mixture of wood ash and demosan fungicide and planted in nursery made of moist sawdust. The minisetts sprouted after three weeks and at four weeks, transplanted to the field prepared under the various tillage methods. 100 kg/ha NPK 15-15-15 were applied at eight weeks after transplanting the seed yam seedlings while soil physical and chemical properties were taken at five months and the harvesting of seed yam done at six months after transplanting the seedlings. Soil bulk density was significantly high with a correspondingly lower porosity in the ploughed plus harrowing plot while the least values were observed in the ploughing plus harrowing plus ridging plot. The organic matter, nitrogen, phosphorus, potassium and the cation exchange capacity were in the medium adequate range for good seed yam growth. Bulk density was a major factor that influenced seed yam performance with the ridged plots producing lower bulk density and higher tuber weight and yield. The tuber weight and yield were comparable in both the mechanically and manually ridged plots.Keywords: Mechanized and manual tillage, comparative effects, soil properties, seed yam yiel