Summary:

In paper analyzed the results of research concerning nitrate and total ni-trogen content in drainage effluents as well as surface water coming from facilities located in Lower Silesia area. Detailed analysis were made for participation of nitrate nitrogen in total nitrogen amount. Drainage effluents were characterized by significant content of total nitrogen: average concentration in research period amounted from 22,4 mg N  dm3 to 36,9 mg N  dm3. In drainage effluents, derived from different drainage section, relation N-NO3:N didn't show significant differences and was in the range 75-88%, despite the fact that this water differed significantly of total and nitrate nitrogen content. The increase of average concen-tration of total nitrogen in surface water for both research objects was cause by outflowing drainage effluents that were reached in nitrogen compounds. In drain-age water in summer period showed smaller relation N-NO3:N, what should be explain by intensive absorbing this ion by plants in vegetation period. Regardless of the analyzed period, there was found higher proportion of nitrate in water below research object. Only in case of lowland object these differences were significant for significant level p=0,05. The more fluctuation of relation N-NO3 conducive smaller participation of nitrate nitrogen in total nitrogen amount in surface water.