Low
potentiality of soil potassium, high multiple crop index, overrain led to scarcity of soil potassium in
hydrographic
net region in south of Jiangsu Province. Potassium loss made by runoff and leakage accounted for 54.4 per cent of potassium application. Owing to scarcity of potassium mine, raising of crop yield and quality improvement of agricultural products, it is not more than 1 out of 10 for potassium fertilizer to satisfy the need of crops. So it is necessary to find resources with enrichment potassium to relax potassium tension.Water,straw,green manure and pond mud are all aboundant potassium resources.Water cycling can supply 14.5 kg/hm\+2 potassium in flatlands region.If there are 2 250 kg/hm\+2 straw returned,the potassium reverted to field will be 45,31.4,and 26.1 kg/hm\+2 respectively for rice,wheat and rape straw.There also is plenty of water green manure,which has high capacity to enrich potassium in water area.If there is enough water green manure returned to field,not only will the potassium lost from field return,but also the eutrophic water will be purified.There also are prolific mud came from river,lake and pond,which contain ample potassium,in
hydrographic net region.Status,
potentiality,problems and countermeasures of potassium resources use were studied in this paper to provide basis for relaxing potassium tension and promoting agricultural sustainability.