Agriculture/3. Arable farming, ground science and agrochemistry

Candidate of Agricultural Sciences Shilov M.P, 1st year student Anisimova E.S

RSE "Kostanai State University A.Baitursynov", Kazakhstan

BIOLOGICAL VALUE OF THE TECHNOLOGIES OF RESTING ON THE SOUTHERN BLACK EARTH OF THE NORTHERN KAZAKHSTAN

Biological diagnostics of new agricultural methods is essential requirement of conservation cropping system of the Northern Kazakhstan. At present time
this situation has particular significance with active implementation of resource saving technologies of crop growing focused on the soil fertility conservancy.

In connection with this, the biological diagnostics of different preparation technologies for complete fallow and cropped fallow were made on the Southern heavy loamy black earth of the Kostanai region. Complete fallow was preparing on zonal technology with 5 mechanical processing. In a cropped fallow the oat mixture with pea was sowed in the second half of summer together with harvest at the end of September. Determination of soil microorganisms was carried out by the appropriate methods.

The experiment showed an active influence of preparation methods the fallow field microbiological regime of the soil (Table 1).

Table 1

Indexes of soil biological activity of complete fallow and cropped fallow, layer 0-20 cm (average for 2008-2011).

Indexes	Complete fallow	Cropped fallow	Wheat fallow
			complete	cropped
The number of microbial association, million/g of soil;	57,6	31,4	33,9	43,4
bacteria:
accounting for the millieu MPA, million/g	12,3	10,4	9,7	10,2
accounting for the milieu SAA, million/g	36,7	17,3	19,4	26,8
Actinomycetes: accounting for the КАА, million/g	8,2	3,5	4,6	6,1
Nitrifying, thousand/g	3,1	1,6	1,8	2,4
Cellulose-decomposing (bacterias+ actinomycetes), thousand/g	347,8	182,1	200,3	292,9
Decaying of soil,%	59,3	35,6	33,5	38,7

In the soil of complete fallow under favorable conditions of temperature, humidity and aeration develop all types of microbial associations rapidly. Dominating position among them (78%) took the microorganisms assimilate mineral forms of nitrogen (bacteria and actinomycetes on milieu SAA). Another common group (21%) are bacteria that use organic nitrogen (accounting for MPA). Broad ratio there between is indicative of intensive crop residues and mineralization of soil organic matter with the production a large amount of nitrate nitrogen. The high number of nitrifying bacteria - 3.1 thousand/g soil indicates on its strong accumulation. The high content of available forms of nitrogen stimulates intense multiplication of cellulose-decomposing microorganisms-347,8 thousand/g. As a result, in the soil of complete fallow there is  activity of microorganisms, accompanied with an intense process of mineralization of plant residues and organic matter. Much tension of microbiological regime is confirmed by general indicator of soil biological activity - decomposition linen. Its disintegration within 30 days averaged 59.3%

Seeding of fallow-grown crop has a significant influence on the course of biological processes. When this happens, in the soil of cropped fallow there is no rearrangement in the microbial composition and change of the dominant forms. However, there is a general reduction in all types of quantitative microbial coenosis. Primarily, the population of microflora consuming mineral nitrogen reduced in 2.1 times. At the same time the reducing of ammonifying bacteria are much weaker (16.8%). This leads to a narrowing of the ratio between microorganisms taken into account on SAA and MPA, and is a sign of attenuation of active processes of mineralization. As a result of the flow rate of productive moisture and biological nitrogen fixation of the oat mixture with pea the number of nitrifying bacteria is reduced to 48.4%. Due to a lack of available forms of nitrogen the development of cellulolytic microorganisms is inhibited - 182.1 thousand/ha. Together, the noted changes reduce the celluloselytic ability of soil. Decomposition of cellulose is 23.7% (absolute value) is less than complete fallow and compose 35.6%. In general, the slowing of soil biological activity in a cropped fallow should be seen as a positive development, conducive to reducing the rates of organic-matter degradation.

When the postcuts of the oat mixture with pea enters the soil late in the autumn that does not significantly alter the level of biological activity. It is connected to the seasonal quantitative decrease of microbial attenuation and its biochemical activity in this period. Therefore the influence of accumulated organic mass for microbiological regime appears in spring next year. However, in the early spring (seed) period biological processes in the soil of complete fallow flow more active. Under the cropped fallow the activity of microorganisms is inhibited in a result of the reduced temperature due to the presence of the oat mixture with pea postcut on the surface. The reflection of these differences is the cellulolytic ability of the soil. In condition of complete fallow the cellulose decomposition degree for 20 days exposure reached 0-10 cm 15,8-22,5 in the layer, at a depth of 10-20cm - 8,8-11,3%. In a cropped fallow the tissue disintegration was less intense - 7,1-10,0 and 12,6-17,4%. During the growing season of wheat microbiological regime undergoes significant changes. The enter the soil of allow-grown crop culture organic mass serves as energy propagation material of all taxonomic groups of microorganisms.

Compared with complete fallow the total number of microbial association increased to 28%. The significant changes indicates to the strengthening of the mineralization processes in the quantitative composition of bacteria which assimilates mineral nitrogen, nitrifying bacteria and cellulolytic microbes. As a result, there is a general increase in biogenic soil, which exhibits in the decomposition rate of cellulose. The cellulose decay energy was higher in cropped fallow than in complete fallow - in the layer 0-10 cm 5,6-7,3, at a depth of 10-20 cm - on 3,3-4,4%. The increasing of biological activity all over the depth of arable layer strengthens the mobilization of available items that improve nutritional conditions in the initial phases. Thus, the biological basis of the cropped fallow technology in the steppes is shown with the help of describing studies. The seeding of fallow-grown crop relieve tensions microbiological processes and reducing the amount of organic-matter degradation in a fallow period. Receipt of plant residues the oat mixture with pea mixture increases the biological activity of the soil under the first wheat.