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Abstract SUMMARY AND CONCLUSIONS This study aims to investigate the effect of preparing sugar beet residues as a waste of extending juse squeeze industry by recycling it in a benefit compost for manuring purposes. from other wise, the newly reclaimed areas of sandy and calcareous soils are in need to continuous supply with organic matter either for improving their properties or for supplying with macor and micro plant nutrients. In order to conduct these objectives, a laboratory work was planed followed with a pot experiment and applied in a field experiment. The laboratory work included tow composting systems, aerobic and anaerobic for 9 months. Sugar beet residues whether resulted from haulms, preparation the roots in field and before squeezing them to obtain sugar were collected, airy dried and chopped into peces one inch long. The bulk quantity was divided into two portions. One of them was composted under aerobic and the other under anaerobic conditions. The samples of each system were taken after 0, 7, 15 days and monthly up to 9 months. The obtained results of that work could be summarized in the following; Organic matter content decreased by time of composition in a rate higher in case of aerobic compost than that in anaerobic one. Humus and organic acids increased by time of composting their concentrations under anaerobic conditions were higher than that under aerobic when the period of composting was longer than 6 months. Total nitrogen increased as a per cent relatively to the continuous decreased in organic matter. In the same time, C/N ratio narrowed gradually by time of composting that ratio was more wide in aneorobic than in aerobic compost. Ammonification process was active through time and produced more ammonia in anaerobic case. Nitrification process activity was detected in aerobic conditions only. Total phosphorus and total potassium followed the same trend of total nitrogen. Ratios of CIP and CIK were almost as the same as CIN. Ash increased as a relative percentage m continuous decomposed material. pH of compost decreased slowly in aerobic case but under anaerobic condition, it was more acidy after 9 months . Cation exchange capacity increased proportionally through aerobic and anaerobic composting but the increases stopped after 7 months in the aerobic compost. Total souble salts in the mixture at 0 time was about 2.1 %. That percent increased gradually recording more high salinity in compost of anaerobic condition up to 2 times of its beginning. Soluble sodium and potassium took the same trend of total soluble salts. The increases in total soluble salts resulted from more soluble ea++ . Water holding capacity in compost samples revealed gradual increases under tow composting systems promoting in aerobic case up to 15 days and in anaerobic on up to 60 days from starting. The curve tended to decrease after that along with composting period. As for moisture content, it gradually increased by time of composting under both systems, but it was higher in the anaerobic conditions which may be due to the closed nature of the system. The pot experiment was planed using three soil samples; sandy. calcareous and alluvial in pots able to 6 kg soil received (half recommended dose, recommended dose and double recommended dose) of aerobic or anaerobic compost. The used compost was one of the three composting periods; 3, 6 and 9 months. Wheat was planted up to maturity as test crop followed with sudangrass which was cut 3 times to study the residual effect of composting additions. Results of that experiment could be summarized in the following: Organic matter content in soil decreased by time of application. That content was high in the alluvial soil followed by calcareous and sandy the lowest one. The soil received aerobic compost contained organic matter higher than that received anaerobic one. Period of 6 month composting was the best but in case of application with anaerobic compost, 9 month composting period was the highest. Increasing dose of application increased proportionally soil organic matter content. Total nitrogen also increased by time of composting . The most significant superior treatment was addition of 4% compost having 6 month composting period under aerobic condition. The best treatment of anaerobic compost was the dose of 4% of the 9 month 120 . composted one. These resulted were uniform in soil samples taken after wheat or sudangrass . CIN ratio differed in their maximum and minimum limits from soil to another. In all soils elN ratio was narrow after sudangrass harvesting than that after wheat harvesting because of the consumption of nitrogen by plant in these soils. The ratio narrowed by increasing dose of compost application in sandy soil especially whhn the preparation of compost was under aerobic conditions. The slight changes in CIN ratio indicated to the equilibrium trend of organic carbon decomposition and total nitrogen presence for that compost. Available phosphorus increased by increasing dose of application. The best period of composting was 6 months for aerobic and 9 months for anaerobic. Alluvial soil contained the highest values of available phosphorus. Available potassium followed the same trend of available phosphorus with an observation that sandy soil lost the highest percentage of its available potassium through the second season. Dry matter yield of wheat and suddangrass was affected by all the studied factors revealing the superiority of alluvial soils, 6 months composting period, aerobic conditions of composting and 4% dose of application significantly to the other treatments in each factor. Nitrogen, phosphorus and potassium content in plant tissues raised by increasing dose of application of 6 months aerobic composting compost followed by that of 9 months anaerobic one 121 with respect to soil properties effect in the order .; alluvial > calcareous> sandy soil. Nitrogen, phosphorus and potassium taken up were of almost the same trends of their concentrations in plants, Dry matter production reflected also its trend. In each soil the supeaor treatment was 4% 6 months aerobic composting compost with superiority of alluvial soil to other soils. A complementary work was established in field by using the most recommended treatment in the pot experimentand compared it with the FYM. The common dose 10 and its double 20 tens/feddan of 6 months aerobic composting sugar beet residues! compost or farmyard manure were applied to an alluvial soil in El-Hamoul area, Kafr El-Shikh Governorate. Wheat was planted after additions as a test crop till maturity . The obtained results of the field experimest could be summarized in the followings: Organic matter content in soil increased by addition of any used amendment to more than its double in unmasured plots . Compost was significantly superior to farmyard manuse at the smae dose. Raising the dose of application of each, caused significant benefit in increasing organic matter content. Total nitrogen in soil was almost of the same! trend of soil organic matter. Carbon to nitrogen ratio was after l5 months of addition wider in plots recevied organic manure with feWdifferences not more than 0.3 within treatments. from that ratio it was found that 122 sugarbeet compost had rapid rate of decomposition more than that of FYM. Nitrate-N after harvesting was about on half to one fourth of ammoniacal N due to plant consumption and leaching by drainage. Both of them increased by treatments 6 - 18 times and 3 - 9 times in the descending orders ; 20 tons compost> 10 tons compost> 20 tons FYM > 10 tonsFYM > control and 20 tons compost> 20 tons FYM > 10 tons compost > 10 tons FYM > control in case of ammoniacal and nitrate-N, respectively. Organic manuring addition increased available phosphorus and potassium in soil in ranges of 150-300% and 10-44%, respectively. The highest values of P and K availability were obtained from treatment of 20 tons compostlfeddan followed with 20 tons FYMlfed higher than 10 ton compost/fed. at 10 tons farmyard manure/fed. came at least of them. Wheat grains and straw yields significantly responded to organic application. 20 tons compost/fed. was significantly superior to other treatments. 20 tons farmyard manure/fed. as the same as 10 tons compost/fed. was significantly higher than 10 tons farmyard manure/fed. Nitrogen uptake appeared significant differeaces between treatments in the order 20 tons compost> 20 tons farmyard manure> 10 tons compost> 10 tons farmyard manure> the control. Phosphorus uptake in wheat grains and potassium in straw followed the same order of yield while phosphorus, in straw and potassium in grains followed that of nitrogen uptake. 123 The final conclusion could be led to the following : Composting sugar beet residues either under aerobic or anaerobic conditions produced better quality organic manure. Increasing period of composting decreased the organic matter content on the produced compst and increased its nutrient availability. In order to increase soil organic matter in the newly reclaimed soils, 3 months composting compost may be the favourete while 6 months aerobic or 9 months anaerobic composting is more favourete in those soils for increasing their supplying power with nitrogen, phosphorus and potassium. In alluvial soils of’El-Hamoul, 10 tons/fed. Sugarbeet compost can be stood equivalent to 20 tons FYMlfed. when the mentioned compost is prepared under aerobic conditions for 6 months. Because of sugarbeet residues accumulated in a limited short period of year after sugar beet harvesting, it can be composted under anaerobic conditions up to 9 months if it was recommended to crops growing in the same season. |