Nitrogen accumulation, cycling and the restoration of ecosystems on derelict land

Abstract. Nitrogen deficiency is the major problem in the creation of new ecosystems on most derelict land. Initially there is insufficient nitrogen in the wastes to drive the new systems, and nitrogen accumulation is, therefore, required. The most cost-effective way of providing this nitrogen is to use leguminous species which fix nitrogen from the atmosphere. Once nitrogen starts to accumulate in the soil management should aim to promote efficient cycling. Maintaining a near-neutral soil pH and a sward with a small C:N ratio helps to increase the mineralization of nitrogen in dead plant residues, and grazing animals also reduce nitrogen accumulation in dead vegetation.