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Z.R. Movsumov Institute of Soil Science and Agrochemistry, Baku, Azerbaijan ABSTRACT In this work the questions of dynamics of connections of nitrogen and its balance are considered depending on entering fertilizers to soil. The norm of losses of gaseous nitrogen from carbonate soils is established. Is shown, that at local entering the efficiency nitric is increased and the unproductive losses are reduced. This way of entering reduces application of nitric fertilizers to 25 %. The method of the investigations: It was applied laboratorial, lizimetical, small-allotment field methods. Dynamics of nitrogen combinations and their balance were studied in different Azerbaijan soils depending on bringing nitrogen fertilizer form, on the depth of their doing up, on soil salted degree, and on the predecessors in rotation links. Carbamide sulfate ammonium and water ammonia were tested form nitrogen fertilizer forms. The investigations were carried out in irrigated meadow-serozem soil. It was revealed that nitrogen ammoniac form bringing in the firm if sulfate ammonium and water ammonia is nitrified for a short time its great part turns into nitrate form, in 26 days after bringing if sulfate ammonium in soil more than 60% of common quantity of nitrogen is discovered in nitrate form, but in bringing of water ammonia in doze of 90 kg/ha, nitrogen about 40%. Comparatively urea is slowly nitrified. For the indicating period in bringing of amid nitrogen (urea) in doze of 60 kg/ha, nitrate nitrogen formed 28,3%, but in doze of 90 kg/ha 24,5 % from general quantity and ammoniac nitrogen. After watering nitrification of urea is strengthened. In bringing of water ammonia, nitrogen main part is preserved in ammoniac form. By the end of plant vegetation (cotton) least quantity of nitrogen remains last occasion, as compared with other forms, watt is explained by most loss of gaseous ammonia in this form. In surface bringing of nitrogen fertilizers in carbonate soil, significant nitrogen loss happens in gaseous form. Our investigations determined that in ammoniac saltpeter, sulfate ammonium and urea brining in carbonate soil, most loss of gaseous nitrogen happens in care of bringing urea, which reach, 26,0 % from bringing. Nitrogen gaseous loss mainly happens in fertilizer surface bringing (0-5 sm.). In doing up of fertilizers in the depth of 10-15 sm. loss of nitrogen decreased to 50%. The investigations on nitrogen form dynamics turning in dependence on salted degree and soil carbonate indicated that gaseous ammonia most loss happens in high carbonate soil. To these soils belong mountain - forestry, where loss formed 16,5% and serozem - meadow from which loss in gaseous form formed 7,5-9,5%. In significant loss discovering in swampy weak- carbonate soil. In some cases straight dependence between carbonate soil gaseous ammonia loss degree is not preserved. Soil salted degree also influences on nitrogen loss from bringing fertilizers. In bringing of urea in meadow-serozem soils, where dense residuum forms more than 1/0%, nitrification processes is depressed, great part of nitrogen remains in ammoniac form and loss in this case reaches 26% from bringing quantity. Dynamics of nitrogen combinations is studied and conditions of lizimetric experiment. Lizimeters were pouring type with size of 100 x 100 sm., the depth 60 sm. The first series of lizimetrsi is under cotton, the second remained without plants, nitrogen fertilizers were brought in the form of ammoniac saltpetre, and sulfate ammonium. It was revealed that nitrate nitrogen most quantity is discovered in upper layers of soil. Nitrate washing in lower layer of soil are compensated by their lifting up with ascending steam, in evaporation. Many investigators consider that in strong rains almost all nitrate nitrogen is leached from root of inhabited layer of soil, from here- the recommendation on nitrification process weakening. The results of our investigations only indicated that not only rain and frequent watering in high irrigation norm don't leach all nitrate nitrogen from soil. For the determination of effective norms in nitrogen fertilizers, the studying of nitrogen balance has a great importance. Balance of nitrogen fertilizers under winter wheat was studied in long ago irrigated bright-chestnut in conditions of bogar brown leached soils, in dependence of predecessors. In nitrogen balance determination under wheat in receipt part of balance was included: entering soil nitrogen with fertilizers, seed plant residuum, formed at expense of accessory crop, at expense nitrogen fixed bacterium, and nitrate entering with atmosphere precipitation. The expense part: nitrogen estranged by main and accessory crop, the loss which in gaseous form are significant. The carried out balance calculations indicated that in control version, where nitrogen fertilizers weren't independently brought from predecessors, nitrogen balance is negative. In monoculture balance intensity formed 56%, after maize 35 and fallow 34%. In bringing fertilizers in minimum doze (N60P45K30) expense part of nitrogen excelled in receipt. So it was in deficit that is balance negative. However balance intensity was higher than in control and formed in monoculture 93% after maize 88,4, after fallow 80 %. In double (N120P90K60) and threefold (N180P135K90) norm, nitrogen balance was positive. In industrial conditions on the whole on Azerbaijan republic balance of nitrogen and potassium is negative, but phosphorus balance is positive. Nitrogen negative balance is mainly connected with increase of its carrying-out as with main as accessory crop. Potassium is in negative balance in connection with potassium fertilizer shortage and its entering soil with low norm. Including bean cultures in rotation decreases nitrogen deficit. However its loss in result of washing and volatilizing in the form of gaseous ammonia, decreases bringing nitrogen fertilizers affectivity. In the purpose of increase nitrogen assimilation coefficient by plants and the increase of return form bringing fertilizer unity. For coefficient increase of nutrition elements assimilation from bringing fertilizers and decrease of their residual negative influence on environment, it is necessary improve fertilizer bringing method. In this connection last time, local method of fertilizer application attracts scientists attention. The investigations on local-band bringing of fertilizers, under winter- bar key are carried out in greyish-brown irrigated Apsheron soil. Fertilizers were brought in the form of nitrofosck, on the depth of 8-10 and 12-14 sm. and for comparison in scattering. Fertilizers (NPK) were brought from the calculation - 100,500 and 25% from annual norm, unreaching part of nourishment elements (N90P90K20) were brought in the from of simple fertilizers. It was determined that the bringing of compound fertilizers (nitrofosk) local-band method promotes forming higher crop of grain. The most crop of barley grain was got, in the full norm (100%) local bringing in fertilizer in the depth of 12-41 sm. (43,0 c/ha). Barley grain crop in local bringing of mineral fertilizers in non-full norm (75 and 50%) , was almost equal to full norm (100%) scattered (continuos bringing). One of the important indices economical efficiency of mineral fertilizers brought under cereals ear cultures, is albumen collection increase with unit of sown area. That's why coefficient of nitrogen assimilation by plants in local method increases and albumen maintenance in barley. If in scattered (continuos) method fertilizer bringing albumen size forms 10,1%, in local method, reaches 12,8% albumen collection, in the first case forms 373,5 kg/ha, but in the second 46,3 kg/ha. In Apsheron conditions, ecological and economical efficiency of local method fertilizer application, was also studied under tomatoes. Fertilizers in the form of ammoniac salt petre, super phosphate and potassium salt in the forms N90P120K60 and N120P150K90 was brought in continuos (in 100% norm) and local in quantity of 100%, and also on 75 and 50% from annual norm. It was determined that local method has not only economical (tomato fruit crop increases 89,9 and 97,1 c/ha) but great ecological significance. In localization of fertilizers, increasing of nourishment elements assimilation coefficient results in significance decrease of nitrate in soil, but favorable conditions creation for the growth and plant development promotes synthesis nitrogen containing combinations and decrease of nitrate accumulation in tomato fruit, that important for industry of ecological pure nourishment products. Thus the studying of nitrogen combinations dynamics in soils of Azerbaijan and their balance in the rotation system gives chance to work out rational norms and methods of nitrogen bringing of nitrogen fertilizers, under different predecessor with calculation of preservation and soil fertility increase. REFERENCES Agayev V.A., and Movsumov Z.R. (1987). Nitrati v rastitelnoy produkcii i agroekologicheskie usloviya ih nakopleniya. In: "Izvestiya AN Azerb.SSR", ceriya Biol.Nauk, 3. Mineev V.G. (1990). Chimizaciya zemledeliya i prirodnaya sreda. Moscow. Movsumov Z.R. (1978). Azot v zemledelii Azerbaijana. 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