The Potential and Coupling Effect of Compost and Mucuna for Quarry Site Restoration: A Study at the YongwaLimestone Quarry in Ghana

摘要

This study evaluated the potential and coupling effect of compost and Mucunapruriens for soil fertility improvement of degraded soil at the Yongwa Limestone Quarry site in Ghana. Compost was produced from a mixture of pig manure and cassava wastes collected from nearby communities, applying simple open windrow technique. The compost was used to cultivate Mucuna, a leguminous climbing plant on degraded plot at the Quarry site. The experimental design included a second plot where Mucuna was planted without compost and a control plot without any intervention. The growth rate of the Mucuna on the plot with compost was about twice its growth rate on the plot without compost. Plot treatment was observed over a period of three months. The control plot with no intervention attracted only one kind of plant species, but planting of Mucuna without compost attracted five different colonising plant species. When the Mucuna was planted with compost amendment, eleven different plant species colonized on the plot, which also showed relatively elevated contents of nitrogen, phosphorous and organic carbon. The increments in the respective soil nutrients were significant. It created a somewhat fertile ground for dispersed seeds of early colonizers to flourish. Another hypothesis was the possibility of broader Mucuna leaves to offer limited but useful protection for shade loving seeds to germinate. The colonizers thrived in close proximity to well-growing Mucuna plants. A symbiotic association was subsequently suggested in which rapidly growing colonisersprovided support for the Mucuna to climb, in return for the benefits these new colonies received from the Mucuna. The potential of the compost/Mucuna intervention in revitalizing degraded land could be applied during decommissioning work to restore quarry or mine sites. The concept could also be extended to local farming communities to help improve soil fertility for crop cultivation. This would limit the dependence on costly chemical fertilizers, while encouraging the production of organic crops.