Mozambique has a variety of regional cropping patterns; agro-climatic zones range from arid and semi-arid (mostly in the south and south-west) to the sub-humid zones (mostly in the centre and the north) to the humid highlands (mostly the central provinces). The most fertile areas are in the northern and central provinces, which have high agro-ecological potential and generally produce agricultural surpluses. Southern provinces have poorer soils and scarce rainfall, and are subject to recurrent droughts and floods.