Effect of Some Physical Factors on Interrill Erosion of Soils in Gidan-Kwanu Area, Nigeria

Savanna regions in Nigeria face environmental degradation and barren land, negatively impacting food and agricultural productivity. Inter-rill erosion occurs due to raindrop impact and transport, particularly on hill slopes. A study was conducted using a sprinkler rainfall simulator and plot experiment to study soil erosion processes. Soil samples were collected from four farms in Gidan Kwanu, with varying moisture content. Sand content ranged from 46.0% to 76.20%, silt from 11.30% to 23.50%, and clay from 11.0% to 30.0%. Uncultivated and bare land had a higher average porosity (15.47% and 14.99%), while cultivated land had lower porosity (14.4%). The study found that most people in Gidan-Kwanu primarily practice farming, which is season-dependent and rain-fed. Soil type and texture significantly contribute to inter-rill erosion, with cultivated and uncultivated soil being more resistant to erosion than bare land soil. The study concluded that farming practices in Gidan-Kwanu are primarily season-dependent and rain-fed. Soil type and texture significantly contribute to inter-rill erosion, with cultivated and uncultivated soil being more resistant to erosion than bare land soil.

Effect of Tillage Practices on Hydro-Physical Properties of Soils in a Rice-Grown Environment in North Central Nigeria

This study details soil’s physical and chemical properties in a rice-grown environment in Minna environs Niger State, Nigeria, under different soil and water conservation practices. Soil samples were collected at 0 - 10 cm, 10 - 20 cm and 20 - 30 cm, respectively, using a soil auger to determine their physical and chemical properties such as moisture content, particle size, bulk density, particle density, porosity and organic matter. The textural classification determined the percentage dominance of the soil types in each study site location. The moisture content of site 1 ranged between 14.3% to 13.7%, site 2 ranged between 13.2% to 10.2%, site 3 ranged between 15.4% to 13.2%, site 4 ranged between 15.6% to 13.6% and site 5 ranged between 16.1% to 10.9%. The clay content of sites 3, 4 and 5 is higher than that of sites 1 and 2, while the silt contents of sites 1, 2 and 3 are higher than that of sites 4 and 5. The mean value of soil organic carbon from each study location was 2.37%, 2.03%, 2.43%, 2.07% and 2.17% for sites 1, 2, 3, 4, and 5, respectively. Therefore, site 1 is susceptible to erosion because of poor infiltration rate and well-ploughed or cultivated land by the tractor (harrowed). The particle sizes analysis indicated that the soil type in Site 1 and Site 2 is mainly sandy loam, while Site 3 and Site 5 are mainly loamy and predominantly clay loam in Site 4.

Effect of Water Application Rate on Growth Parameters of Farro 44 Rice Grown in a Selected Irrigation Scheme in Niger State, Nigeria

Water and land are the necessary agricultural inputs, and both are scarce these days. This study aims to determine the effect of water application rate on selected planting and crop parameters of Farro 44 rice during dry season farming and its growth response. The randomised complete block design was employed for the Farro 44 rice variety, with each plot size 4 m2 (2 m × 2 m) for ease of monitoring. A 0.3 m bound space separated each plot. The crop spacing was 0.2 m × 0.3 m, 0.3 m × 0.3 m, and 0.3 m × 0.4 m, respectively, for the row-to-row and plant-to-plant distance. The data collected were statistically analysed. The height of the faro 44 variety of rice ranged between 35.50 cm to 44.00 cm for plots with 2 tillers per hill, while that of 4 and 6 tillers per hill ranged between 35.50 cm to 41.40 cm and 35.50 cm to 39.30 cm, respectively. Minimum damage of 2.32% was seen for plant hills of 2 tillers, while 9.21% and 11.89% were observed for tillers of 4 and 6, respectively. It was seen that plots with the highest spacing of 30 × 40 cm and tillers of 2 per hill were observed to perform better than those of the other plots within the experimental pots. Such plots had a maximum plant tiller of 37 when counted, with the height of the plants reaching 44 cm after 70 days of planting. In conclusion, farmers within the study area of the Kanko community in Niger State. Nigeria appears not to have any known knowledge of the soil they are cultivating and the water they use as a source of irrigation within the farming areas. It was further concluded that the rice crops would be produced maximally with minimal water application to the rice field.

Characterisation of Hydrological Drought and Implications for Sustainable Water Resources Management in the Sokoto-Rima River Basin (SRRB), Nigeria

Hydrological drought is usually characterised by water loss over time from both underground and surface supplies. Thus for this study, the assessment of hydrological drought was carried out by employing Cumulative Rainfall/Streamflow Anomaly as preliminary tools for the presence of drought signatures while detailed characterisation was via Streamflow Drought Index (SDI). The results revealed that hydrological drought was observed in all the stations;however, though in general, the stations could be classified as experiencing near normal drought conditions with mild drought signatures. The findings also revealed that the average streamflow deficit volume and durations of the hydrological drought severity were 1.780 Mm3 and 192 months, 1.444 Mm3 and 252 months, 3.148 Mm3 and 252 months, and 0.159 Mm3 and 372 months for Bakolori, Goronyo (pre dam construction era), Goronyo (post dam construction era) and Zobe stations, respectively. The results also revealed the relevance of flow duration curve and analysis of frequency of drought state transition for the development of scenario-based basin water resources management protocol. The coefficient of determination (R2) statistic of the developed regression models indicate that 73.3% and 86.5% variation in streamflow dynamics across the Basin can be explained by climate change variables. However, for sustainable management of water resources in the Basin, it is imperative that characterisation of hydrological drought and monitoring should employ robust indices which use improved monthly precipitation estimates under global warming scenario in addition to ensuring that there is a shift from reactive to proactive approach in order to combat hydrological risk. Hence, a robust framework that finds application both for planning mitigation actions which embody strategic, tactical and emergency components should be designed;to this end, analysis of persistence and recurrence of drought in time and determination of possible recurrent patterns are necessary.

Effects of Model Structural Complexity and Data Pre-Processing on Artificial Neural Network (ANN) Forecast Performance for Hydrological Process Modelling

The choice of a particular Artificial Neural Network (ANN) structure is a seemingly difficult task;worthy of relevance is that there is no systematic way for establishing a suitable architecture. In view of this, the study looked at the effects of ANN structural complexity and data pre-processing regime on its forecast performance. To address this aim, two ANN structural configurations: 1) Single-hidden layer, and 2) Double-hidden layer feed-forward back propagation network were employed. Results obtained revealed generally that: a) ANN comprised of double hidden layers tends to be less robust and converges with less accuracy than its single-hidden layer counterpart under identical situations;b) for a univariate time series, phase-space reconstruction using embedding dimension which is based on dynamical systems theory is an effective way for determining the appropriate number of ANN input neurons, and c) data pre-processing via the scaling approach excessively limits the output range of the transfer function. In specific terms considering extreme flow prediction capability on the basis of effective correlation: Percent maximum and minimum correlation coefficient (Rmax% and Rmin%), on the average for one-day ahead forecast during the training and validation phases respectively for the adopted network structures: 8 7 5 (i.e., 8 input nodes, 7 nodes in the hidden layer, and 5 output nodes in the output layer), 8 5 2 5 (8 nodes in the input layer, 5 nodes in the first hidden layer, 2 nodes in the second hidden layer, and 5 nodes in the output layer), and 8 4 3 5 (8 nodes in the input layer, 4 nodes in the first hidden layer, 3 nodes in the second hidden layer, and 5 nodes in the output layer) gave: 101.2, 99.4;100.2, 218.3;93.7, 95.0 in all instances irrespective of the training algorithm (i.e., pooled). On the other hand, in terms of percent of correct event prediction, the respective performances of the models for both low and high flows during the training and validation phases, respectively were: 0.78, 0.96: 0.65, 0.87;0.76, 0.93: 0.61, 0.83;and 0.79, 0.96: 0.65, 0.87. Thus, it suffices to note that on the basis of coherence or regularity of prediction consistency, the ANN model: 8 4 3 5 performed better. This implies that though the adoption of large hidden layers vis-à-vis corresponding large neuronal signatures could be counter-productive because of network over-fitting, however, it may provide additional representational power. Based on the findings, it is imperative to note that ANN model is by no means a substitute for conceptual watershed modelling, therefore, exogenous variables should be incorporated in streamflow modelling and forecasting exercise because of their hydrologic evolutions.

Soil Detachment with Organic Mulching Using Rainfall Simulator in Comparison with a Short Duration Natural Rainfall for Effective Soil Conservation

The impact of raindrop on sandy soil was studied using rainfall simulator and natural rainfall to determine average soil detached. Erosion by rainfall is one of the major hazards threatening the productivity of farmlands. This study determined the rate of soil detachment in comparison between natural rainfall and simulated rainfall for effective soil conservation measure. The height of the simulator was varied considering the diameter of the nozzles which were considered during the design stage of the rain simulator. Two plots of dimensions 2 m × 2 m each were cleared with one considered for bare and treated soils for both the natural rainfall and simulated rainfall. Splash cups were installed on each of the plots at half depth of the cup after the clearing of the area at 0.4 m × 0.4 m apart. Two sets of rain gauge were placed at the experimental site to note the volume of natural rainfall on the farm. The average soil detached was analysed using statistical analysis where t-test was also carried out to know the difference in mean. There was a significant difference in the degree of soil detachment between bare and treated soil under natural rainfall experiment;t(18) = 8.917, p < 0.01. The mean of the natural rainfall for the bare soil was 11.6910 compared to that of the treated soil of 7.75. Size of effect (Eta-square (η2) = 0.8154) reveals that the nature of soil accounted for 81.5% variance in the average detachment rate. For simulated experiments with a mean value of 7.3360 have higher tendency of detachment than treated soil with a mean value of 4.2240. Size of effect (Eta-square (η2) = 0.630) reveals that the soil types accounted for 63% variance in the average detachment. It was concluded that 40.33% soil was found to be conserved using the cow dungs mixed with bare soil to compact the soil. The nozzle size, simulator height, rainfall intensity and other rainfall parameters all contributed to the amount of average soil detached.

Effect of Land Management on Soil Hydraulic Conductivity in Gidan Kwano, Niger State, Nigeria

Hydraulic conductivity is one of the most important parameters for flow and transport related phenomena in soil and also a criterion for measuring soil ability to transfer water. There is concern arising from the suitability, efficiency and ease of the different measuring methods use under different land management practices. The purpose of this paper is to determine and evaluate soil hydraulic conductivity under different land management practices which include forest land (teak and Melina plantation), grassland and maize cultivated land using the constant head method. The measurement is at different depth of 0 - 15 cm, 15 - 25 cm, 25 - 50 cm, 50 - 75 cm. The limited means of each land use were used to compare the result obtained through statistical means. All tests were carried out using SPSS at a significance level of 0.05. An ANOVA test was conducted to check if each of the land use is significantly different. The soil in forest zone (Teak plantation and Gmalina plantation) had a significantly high bulk density as 1.7533 cm-3 and 1.6967 cm-3 respectively at depth 50 - 75 cm compared to the low bulk density in the grass, maize cultivated land as 1.5000 cm-3 and 1.4833 cm-3 respectively at depth 50 - 75 cm. However, soil hydraulic conductivity was significantly high in the grass site or soil at the surface with 2.8833 cm·h-1. Results obtained from the different land use serve as Knowledge of variability of soil that can assist in defining the best strategies for sustainable soil management through the provision of vital information for estimating soil susceptibility to erosion, hydrological modelling and efficient planning of irrigation projects.

Spatiotemporal Variation of Land Use Pattern and Land Cover Changes in Gidan Kwano Watershed Area in North Central Nigeria

Land Management Systems (LMS) are institutional frameworks complex by the tasks they must achieve, national, cultural, political, and judicial settings and technology. The urbanisation process in Nigeria has increased since the 1960s because of the crude oil boom era and other government-backed industrial initiatives and investments. This study employed the use of both primary and secondary sources of data. Preliminary data comprise methods of land use, types of agricultural activities carried out and the process of working on the land by the farmers within a 10 km radius. The secondary data involved the interactive digital and visual techniques of the Geographical Information system for five seasons, with each having a ten-year interval span within 1975 to 2015. Statistical analysis was carried out with SPSS 2013 and XLSTAT 2015. Five land use and land cover types were observed within the Gidan Kwano watershed, which includes wetlands (WL), water bodies (WB), bare grounds (BG), vegetation (VG), and settlements (SL). The most prevalent landform in the study area during the 1975 period was the vegetative area which was 50% of the total landmass. Thus, the vegetation (VG) covered half of the Gidan Kwano watershed. However, the vegetative area decreased substantially during the study period of 1975 to 2015. It was observed that the vegetation (VG) within the study area had the highest percentage of coverage, of 34%. During the study period, a significant decrease was observed in the WL, WB and VG areas. It was also concluded that due to the built-up places, the infiltration of surface runoff from rainwater would be drastically reduced as most of the sections are paved for construction activities while a section of the study area is covered with rock outcrops and farmlands.

Evaluation of Temporal Changes in Deep Well Water Quality in Igabi Local Government Area of Kaduna State

The research work was carried out in Igabi Local Government of Kaduna State. Thirty water samples from boreholes were randomly collected within the major towns in November to April (Dry), and May to October (Rainy season). The samples were analyzed for physical, chemical, and bacteriological parameters and to observe any changes in the groundwater quality of the area. Analysis of variance (ANOVA), Pearson Correlation were performed on the data obtained using SPSS 10.0 for a window for significant variations and inter-element relationship. High mean turbidity was recorded in boreholes in Danfili (12.2 NTU), Kwarau (6.2 NTU). Mean turbidity of 4.3 NTU was recorded in Dry season for wells with Rigachikun having 5.1 NTU. It was observed that a negative correlation exists between well depth and heavy metal concentration. There was also a linear relationship of 0.686 between well distance and nitrate (faecal contaminant). Mean value for Fluoride (0.22 mg/l), Sodium (20.78 mg/l), Calcium (15.7 mg/l), Iron (0.013 mg/l), Nitrate (3.69 mg/l), Cadmium (0.00102 mg/l) Chloride (22.107 mg/l) recorded for sampled wells were all within WHO standard. A high value of 24 mg/l and 25 mg/l for Nitrate was recorded in Saminaka Road and Danfili. An indication of contamination during the rainy season indicates surface-groundwater intrusion (influx). The results of the bacteriological analysis indicated that most wells sampled have a range of 1 cfu/100 ml to 7 cfu/100 ml with Danfili Mani having the highest value (7 cfu/100 ml) which make it unsaved (not Potable).

Conditional Heteroscedasticity in Streamflow Process: Paradox or Reality?

The various physical mechanisms governing the dynamics of streamflow processes act on a seemingly wide range of temporal and spatial scales;almost all the mechanisms involved present some degree of nonlinearity. Against the backdrop of these issues, in this paper, attempt was made to critically look at the subject of Autoregressive Conditional Heteroscedasticity (ARCH) or volatility of streamflow processes, a form of nonlinear phenomena. Towards this end, streamflow data (both daily and monthly) of the River Benue, Nigeria were used for the study. Results obtained from the analyses indicate that the existence of conditional heteroscedasticity in streamflow processes is no paradox. Too, ARCH effect is caused by seasonal variation in the variance for monthly flows and could partly explain same in the daily streamflow. It was also evident that the traditional seasonal Autoregressive Moving Average (ARMA) models are inadequate in describing ARCH effect in daily streamflow process though, robust for monthly streamflow;and can be removed if proper deseasonalisation pre-processing was done. Considering the findings, the potential for a hybrid Autoregressive Moving Average (ARMA) and Generalised Autoregressive Conditional Heteroscedasticity (GARCH)type models should be further explored and probably embraced for modelling daily streamflow regime in view of the relevance of statistical modelling in hydrology.