Valuing groundwater recharge through agricultural production in the Hadejia-Nguru wetlands in northern Nigeria
用生产函数法评估尼日利亚北部湿地地下水补给对旱季农业的价值，通过调查数据计算每公顷灌溉地的经济价值，并模拟补给变化对福利的影响。
This study applies a production function approach to value the groundwater recharge function of the Hadejia-Nguru wetlands of northern Nigeria. The groundwater recharge function supports dry season agricultural production which is dependent on groundwater abstraction for irrigation. Using survey data this paper first carries out an economic valuation of agricultural production per hectare of irrigated land. We then value the recharge function as an environmental input into the dry season agricultural production and derive appropriate welfare change measures. Welfare change is calculated using the estimated production functions and hypothetical changes in groundwater recharge and hence, groundwater levels. By focusing on agricultural production dependent solely on groundwater resources from the shallow aquifer, this study establishes that the groundwater recharge function of the wetlands is of significant importance for the floodplain.