No abstract

No abstract

This paper provides a broad overview of issues on groundwater condition and management in the Kano region of northwestern Nigeria. The aim is to recommend new management strategies that can ensure sustainable groundwater resource management in the region. To achieve the aim of the study, various studies on groundwater conducted in the region were reviewed and key issues were identified. The review revealed that groundwater availability varied between the Basement Complex and Chad Formation areas of the region, with the latter having more of the resource than the former region as a result of the migration of groundwater from the Basement complex to the Chad Formation region. The review also revealed a steady annual decrease of groundwater level during the period 2010 to 2013 and the groundwater beneath the floodplains dropped from 9000 Million Cubic Meter (MCM) in 1964 to 5000 MCM in 1987 in the Chad Formation area of the region. The review further revealed that there is poor knowledge regarding the impact of historical and projected climate variability and change on groundwater availability in the region. This is as a result of the lack of sustained time series data on groundwater resource. Thus, there has been little or no integrated management between groundwater excess and deficiency on one hand, and groundwater pollution management on the other hand. Rainwater harvesting, among other approaches, is recommended for sustainable groundwater management in the region.

No abstract

No abstract

Detecting and predicting the impact of land use/land cover (LULC) changes on streamflow are crucial sources of information for the effective management and protection of land and water resources in Sahelian ecosystems such as the Hadejia river basin. In this study, LULC change detection was performed using ENVI, while the LULC modeling was conducted using the cellular automata (CA)–Markov in the IDRISI environment. However, the streamflow trend and variation were assessed using the Mann–Kendall (MK) trend test and the inverse distance weightage (IDW). Before the LULC modeling and projection (2030), the LULC was classified for 1990, 2000, and 2010 using supervise classification. Model output revealed a strong relationship between LULC and streamflow trend, thus, the decade 1990–2000, was the decade with high forest clearance and streamflow output, consequently severe floods. However, the decade 2000–2010 witnessed land use expansion mainly via construction (3.4%). Meanwhile, the scenario will slightly change in the future as agriculture is projected to expand by about 9.3% from 2010 to 2030 due to the increased human population. Thus, food insecurity aggravated by climate change should be anticipated, and measures to avert/reduce their effects must be initiated.

The current review has unveiled the spatial disparity of the surface water resources availability between the upstream and downstream of the Hadejia River Basin (HRB). The surface water resources are more abundant in the upstream areas of the basin. Although rainfall and temperature dynamics are identified as the major reason for these spatial variations, other important factors include the differences in the geological formation and the land use changes. Furthermore, the differences in the geological formations between the upstream and downstream areas have further widened the disparities in the surface water resources available across the basin which are motivated by the differences in the rate of infiltration. The combined effects of these factors affect both spatial availability and the quality variation of the surface water resources. However, as per this review, there is no single integrated study reported to have aimed at addressing the problems of water resource excesses, deficiencies and/or pollution throughout the basin. To address the problem of water pollution, floods, and droughts, the current review recommends the use of riverbank filtration (RBF), aquifer recharge and recovery (ARR) and rainwater harvesting.

No abstract