**Author details**

#### C.A. Igwe

tisol in southeastern Nigeria, the tolerable soil loss was about 10 t ha-1 y-1 under maize pro‐

Therefore, the suggested soil conservation measures based on the agricultural land use is recommended for the entire agro-ecological system. The land use option suitable to the area should be that based on integrated watershed management with arable farming, agrofores‐ try and intensive afforestation. These practises are considered cheap option which can be af‐ forded by the rural poor farmer. The methods are also very sustainable and not destructive to the agricultural land. This is aimed at reducing the annual soil loss rate and prevents the development of fresh gullies in the area. Agricultural land use should be based on topo‐ graphic variations, major soil distribution, soil potential erosion hazard, hydrology and oth‐ er geomorphological variables. Igwe [4] recommended that the entire region should be partitioned into 4 broad sections based on their location on the landscape. The lowlands and valley floors which also contain sediments should be put to rainfed and irrigated farming of arable crops. The main soil conservation strategies should be those that improve plant nu‐ trient availability, land levelling in case of irrigation and drainage. On the land areas that are on 5% slope and below, the regular recommended cultural practises of organic matter appli‐ cation to the soil is suggested while mulching, crop rotation and well managed agro-forestry are some of the ways of keeping the soil uneroded. Crop residues in association with tillage systems contribute immensely in the conservation of the soil or other wise. The other re‐ maining 2 land units are those that vary between 5-30 % slope and mostly the sites of cata‐ strophic gullies in the area. They should be permanently forested and may be used for wildlife conservation. The kind of forestation should be that which produces intimate multistoreyed association of woody species, grasses and creeping legumes. This will ensure steady cover for the bare soil and offer some kind of protection to the soil against the high intensive and aggressive rainfall. The major soil conservation strategies are broad-based ter‐ races and cover cropping of bare soils. A more comprehensive soil conservation method will involve the application of certain hydrological or bioenvironmental processes so as to con‐

Soil erosion in the form of gullies is very common in southeastern Nigeria. This review has shown the influence of geology, climate, geomorphology (slope), vegetation, man and soil it‐ self on gully development and soil erosion in general. Typical empirical examples are cited from previous works from other researchers in other parts of the world and locally. Past works on estimation of potential soil erosion hazard in the region indicate that more than 1.6% of the entire land area has been devastated by gullies. The inherent characteristics of the local soils to a large extent promote the spread of soil erosion especially the gully type in the region. The roles of anthropogenic factors with regards to land use and its influence on the vegetation are considered. The serious deforestation of the vegetation and poor revegetation or afforestation programmes have all contributed to the catastrophic erosion hazards. General strategies for

duction, with appreciable loss in the production capacity of the soils.

trol the overland flow and excessive runoff.

**11. Conclusion**

168 Research on Soil Erosion Soil Erosion

Address all correspondence to: charigwe1@hotmail.com

Department of Soil Science, University of Nigeria, Nsukka, Nigeria
