An expert in Soil Physics at the Federal University of Agriculture, Abeokuta, Professor Johnson Adesodun, has lamented that Nigeria down graded the relevance of soil to life and has, therefore, not been adequately managing its soils for sustainable development.
Prof. Adesodun, who was discussing his recent research into options to organic fertiliser in farming and the importance of the soil in the process, argued that soil was fundamental to life itself on earth.
“So, whatever we do, whether agronomic or non-agronomic projects, it is expected that a soil test is first carried out. Some come for soil test when they need to get a bank loan, which requires land evaluation. But generally, people do not carry out these tests and that is why we have low yield from our agricultural activities, as well as failed projects such as roads and buildings,” he stressed.
Recommending an alternate source to the use of organic fertilizer in farming, the soil physicist, who is also the Head, Department of Soil Science and Land Management, College of Plant Science and Crop Production (COLPLANT) at FUNAAB, said a weed plant, the Mexican Sunflower (tithonia diversifolia), when applied fresh as green manure at 10 tons per hectare, provides the same nutrients as other types of manure. This, the don explained, made it highly suitable for the kind of soil found in Nigeria.
He explained that the Mexican Sunflower was introduced to West Africa as an ornamental plant, but could grow and suppress other plants, making it a serious threat to farmers, hence, he decided to carry out a research on it.
In the course of the research, he said he realised that when the weed plant was freshly harvested, chopped and ploughed back into the soil, it served as a good source of fertilizer for the soil, saying that the application of compost manure would have produced the same result.
Prof. Adesodun added that other plants that could also serve as good sources of fertilizer include panicum maximum and chromolina rodorata, which are commonly available as weeds throughout the country.
The lecturer said his research focused on the effects of different land management practices occasioned by the addition of various kinds of organic and inorganic amendments on soil physical properties as related to carbon and nitrogen sequestration, structural stability, crop production and environmental protection.
Prof. Adesodun stated that the motivation to embark on his line of research was primarily borne out of the need to manage the physical quality of the soil.
“It is important that the physical environment of the soil is properly managed. For example, one should ensure that when it rains, the water filters through the soil properly without causing erosion and that when fertilizer is applied, the soil has adequate soil water to make it available to the plant in order to avoid the case of the soil being chemically fertile and physically infertile.
“So, it is a combination of physical, chemical and biological management of soil that will have good soil quality. That was what really motivated me. As soil physicists, we look at the physical aspect of the soil, in collaboration with other researchers,” he stated.
Saying that he was not against the use and application of both organic and inorganic fertilizers, the researcher stated that there was, however the need to prepare the soil adequately such that the fertilizer applied would not be lost
He said if the soil was not well managed – physically, biological or chemically – it would not give the desired yield.
“You cannot just dump manure or poultry droppings on land. You also have to improve the physical quality of soil. Application at 10 tons per hectare is very adequate for our fragile soils here. The common manure is poultry manure because of what has been used to compound the feed. Poultry manure is the best, when compared to other types,” he maintained.