River and groundwater nitrogen contamination caused by livestock production

Water quality of rivers in Japanese domestic dairy and pig raising regions, as well as the groundwater in these regions, was investigated. Regarding t he method of disposing livestock excreta, interview results from the livest ock production farmers and the results of water quality analysis were evalu ated. It is concluded that the rivers and the groundwater were contaminated due to inappropriate disposal methods of the livestock excreta. The concen trations of ammonium nitrogen and nitrate nitrogen in the rivers and ground water were high. The sludge from the bottom of the rivers was also investig ated and bacteria which are characteristic of excreta of dairy cattle and p igs were detected. The above pollutants were, therefore, considered to be o f livestock.