Sessions

Session - Nutrient Dynamics I and II

Nitrogen and Phosphorous Dynamics in Co-Composted Yard Debris and Broiler Litter.

LEWIS, CARR (1), Chris, Prigge (2),Gary, Felton (3), John Bouwkamp (4)

(1&3)Department of Biological Resources Engineering;(2&4) Department of Natural Resources Sciences and Landscape Architecture, USA

Manure nitrogen and phosphorous issues have come to the forefront in Maryland. In 1998 the Maryland Legislature passed the Water Quality Improvement Act mandating nutrient management plans for the application of livestock and poultry manures, compost and commercial fertilizer. In Maryland approximately 375,000 tons of broiler litter is produced annually. Some of the litter goes to composting. The question often is asked what happens to the nitrogen and phosphorous in the composting process? To more definitely answer this question an experiment consisting of 4 treatments has been designed. An in-channel agitated bed composter will be used. The channel is 2 meters wide and 55 meters long. A turning machine operating on rails will be used as the turning device. The channel also has the capability of using negative aeration systems. Four treatments will be made in the channel and each will be separated by a distance of 5 meters. The treatments are: (1) turned without aeration; (2) turned with aeration; (3) aeration turned occasionally; and (4) static turned occasionally. Each treatment will be made utilizing broiler litter and ground yard debris. Each treatment will consist of a 1:1 ratio of the feedstocks. The treatments will be mixed with a box manure spreader before placement into the compost channel. Initial moisture will be adjusted to 50 percent. The following data will be collected daily (weekdays) at three locations within a treatment: (1) temperature; (2) moisture; and (3) oxygen. Once per week samples will be collected for organic and inorganic nitrogen and total and soluble phosphorous analysis. The data mentioned above will be collected for the primary composting phase and the final samples at the conclusion of the secondary composting phase. The primary composting phase will be for 30 days and the secondary phase will be for 30 days. Data are not available for inclusion in this proposal but will be completed for the final paper.

Dynamics of Carbon and Nitrogen in Waste Water Sludge Composting

DRUILHE, CELINE (1), de Guardia, Amaury (1), Rogeau, Didier (1), le MouÃ«l, Nausicaa (1)

(1) Livestock and municipal wastes management, Cemagref, France

During composting of organic wastes, the fermentation stage includes a multitude of physico-chemical, microbiological and thermodynamic phenomena. These phenomena induce transfers of solid organic matter towards the soluble phase via digestion by bacterial enzymes, consumption of dissolved organic matter by micro-organisms for their metabolism, and transfers between aqueous and gas phases. In the context of these previous phenomena, the dynamics of carbon and nitrogen are studied on a waste water sludge composting experiment on an industrial site. The initial substrate is a mixture of biological sludge, coming from a paper manufacturing company, added to crushed wood pallet in a 1:3 volume ratio. The process consists of a pre-heating phase and a static fermentation phase in a bin under forced negative aeration, with one material turning. The bin is instrumented for collection of all necessary data for the study of carbon and nitrogen dynamics. In addition to the measurement of process and control parameters (aeration rate, temperature€¦), material evolutions and characterization of in-going and out-going flows during fermentation are monitored. Physico-chemical characterization of the material is regularly checked on five distinct fractions : water, water-soluble fraction (dissolved fraction) and three solid granulometric fractions (non dissolved fractions). The mass changes of the different parameters (organic matter, mineral and organic carbon and nitrogen€¦) within each fraction then make it possible to understand their specific role in the global change of material and to identify the reactive fractions. The condensates and leachates released are quantified and characterized daily. The in- and out-going gases temperature, moisture, pressure and composition in O(2), CO(2), CH(4), NH(3), N(2)O, NO(x) are also continuously monitored during fermentation. This work has been realized through the Polivalor R&D program, associating Cemagref and SITA with the financial contribution of ADEME (French agency of environment).

Investigations to the Nitrogen Management in Composting Processes

I. KÃ–RNER and R. Stegmann

, Germany

A municipal solid waste at a high organic content was composted under different conditions. 6 experiments simulated in-vessel composting. They were carried out in a laboratory composting unit using 100 L bioreactors. 2 experiments simulated an open system and were carried out in piles. The amount of structural materials, aeration and turning rates were modified. Besides the general parameters which determine the course of composting (such as: temperature, moisture, pH, CO2-production) parameters which affects nitrogen management (total N, NH3-N, NO3-N, NO2-N in substrate and leachate; NH3-N and NOx-N in exhaust gas) were measured. As results nitrogen balances for the different tests will be presented. Their differences will be discussed in dependency of the influencing parameters. Especially the rate of aeration had a high impact on nitrogen dynamics. Based on the results possibilities for nitrogen management in in-vessel and open system will be presented. On application, the compost N content and its binding form plays an important role. The demand of N differs, depending on application. There are situations where composts with a low total N-content are needed, e.g. for land-reclamation by giving structural improvement only. But in most cases, plant grow shall be enhanced. If composts shall be used as a fertilizer, the total N-contents should be high - but with a high inorganic N-proportion. The effect of different composting mechanisms on the plant growth will be presented by means of plant tests (barley, cress) using the different composts, produced during differently operated in-vessel and pile tests.

Phosphorus Dynamics During Composting of Beef Cattle Feedlot Manure.

LARNEY, F.J., Hao, X., Miller, J.J. and Olson, A.F.

Agriculture and Agri-Food Canada, Research Centre, Lethbridge, Alberta, Canada

Manure composting is being increasingly adopted by the beef feedlot industry in southern Alberta. Several studies were established at the Lethbridge Research Centre to examine the effect of composting on nutrient changes in manure. This presentation will discuss changes in total and available phosphorus (P) as raw manure becomes compost. P concentrations generally increased during the composting process. This was due to loss of dry matter mass but maintenance of P mass during composting. This resulted in the same amount of P present in less dry matter, constituting a P concentration increase. Total P concentrations of raw manure were generally in the 0.3-0.45 % range. In compost, total P concentrations were in the range 0.45-0.6%. Available P levels generally increased from values of 1000-2500 mg kg(&-1) in raw manure to values of 2500-4000 mg kg(&-1) in compost. Implications of P dynamics during composting will be discussed with respect to haulage requirements of P in the form of raw manure or compost.

The Interactions of Mushroom Compost and S,On P-Soil

Ali Reza Guiti

IDRC-Tehran University, Iran

Loss of organic matter, Sailinity , low CEC, diminished Water retention, low availability of P( in presence of high amount of total p) are the common problem of arid zones. P- Fe and Zn deficiency , induced by high amounts of Ca and Ca+Mg, decreased plant yield. High amounts / of chemical fertilizer, increase the soil salinity. This study was planned , to determine if different amounts and combinations of compost, supplemented or not by sulfur, could partially replace inorganic P-fertilizers. The field experiment was performed based on a completely randomized factorial design, with four replications. The treatments used were : 3 levels of compost (0 - 20 and 40 tons per hectare; 4 levels of elemental sulfur :( 0-8 -16 and 32 tones per hectare) , and 3 kinds of N-inorganic fertilizers : ( urea, ammonium nitrate and ammonium sulfate). Sorghum seeds were sown, and 144 plots were manually and separately irrigated. Growing period prolonged 95 days , thereafter, the plants were cut, weighted and dried. The main soil characteristics were pH =8,ECe =4.3 milli mho per Cm, total N% = traces , organic carbon %= lraces. Mushroom compost , contained 2.09 % N , OM % = 70.8 , PH=7 , ECe =11 mili mho per cm , C% = 28.9 and C :N = 13.8. Important soils and plants parameters were determined. Statistical analysis of the data revealed that considerable variability exist between the control and all other treatments with respect to their effect on yield and total protein contents. WUE improved netly according to the treatments. The soil extractable P, (Olsen) has showed interesting results. It seemed that application of sulfur , not only proved the plants with sulfate , but also reduced the soil pH( in microsites), and rended fixed nutrients , such as P, Fe and Zn , more available . Highly significant compost - S interactions were seen too. The addition of inorganic fertilizers to compost, resulted in higher enzyme activity than compost alone, but , had a little effect on C- mineralization. The soil fertility was improved by increased composts amounts. The residual effects of these treatments , will be studied during 3 years. In conclusion , it seemed that increasing compost consumptions by the farmers, completed with or not S , and some other elements , is a very good remedy for arable soils of IRAN. Certainly more and more research should be undertaken and discussed to determine the best formulation for conditioning and fertilising soil.

Proper Use of Compost Avoids Soil Nitrogen Overload

Heribert Insam

Univ. of Innsbruck, Inst. Of Microbiology, Innsbruck, Austria

Nitrogen mineralisation from composts applied to soils depends on several factors, like compost quality, soil properties, or climatic attributes. Plant nitrogen uptake, on the other hand, depends on the crop and crop management, and the dynamics of uptake is much related to climatic and seasonal differences. Net nitrogen releases are thus hard to predict, but current knowledge offers solutions. This paper deals with the problems of nitrogen losses, possible contamination of groundwater, nitrogen deficiencies and nutrient imbalances after compost application. It will be shown how composts should be analyzed, stored and used to avoid nitrogen related environmental and plant nutritional problems. The paper also addresses current European compost legislation related to nitrogen release.

Nitrogen Dynamics in Potted Rice Ecosystem Fertilized with ¹⁵N-Labeled Composts and ¹⁵N-Labeled Urea.

LIANGGUO LUO (1) Sumio ITOH (2) and Motohiko KONDO(2)

(1) Sustainable Agriculture Research Group, Dept. of Macro-agriculture Research of Chinese Academy of Agricultural Sciences, (2) Lab. of Paddy Soils and Fertilizers, Dept. of Soils and fertilizers of National Agriculture Research Center of Japan., Japan

The use of considerable chemical fertilizers in agriculture production has put large pressure on the ecological environment, especially caused global warming and groundwater pollution. Organic agriculture as a substitute is gradually developed in the world and is taking more and more important role in improving and enhancing the ecological environmental harmony. The aim of this paper is to study the dynamic of nitrogen from (&15) N-labeled fertilizers input including rice straw compost, cattle compost and urea in greenhouse potted paddy rice ecosystem during 5 months with(&15)N tracer and dilution technique and static chamber technique. The experimental soils originated from the surface soils treated by compost and chemical fertilizer respectively for near to 80 years in the Long-term Fertilizers Experimental Station of National Agriculture Research Center (NARC) of Japan. This was a random labeling design with matching four fertilizer treatments and three replications in two kinds of soils. Kinnhikari ( one kind of Japanese rice varieties) was grown in the soils. The greenhouse gas N(2)O emission were measure by a gas chromatograph equipped with a (&63)Ni electric capture detector (ECD), inorganic ammonia and nitrate and nitrite were analyzed by TRAACS 800 auto-analyser. The ratios of nitrogen uptake by rice plants and residual nitrogen in soil from composts and chemical fertilizer were determined by measuring (&15)N-atom% enrichment with a (&15)N analyser. The results positively showed that the application of composts can effectively lower the environmental pollution and destruction caused by application of chemical fertilizer. Recovery of ((&15)N from labeled composts by soil-plant system was higher than that from chemical fertilizer.

USDA-ARS, Beltsville, MD and Kearneysville, WV, USDA-ARS, USDA-ARS,(1)Beltsville, MD and (2)Kearneysville, WV, USA

Animal manure management can have significant impact on both ground and surface water quality. Recently, P levels in agricultural soils have been the focus of research because inputs into agricultural systems are out of balance with outputs. Historically manure addition was made according to the N requirement of the crop and, subsequently, exceeded the crop P needs. Composting reduces by almost half the available or soluble N in manures but studies using poultry manure and cattle manure suggested that composting does not similarly reduce the soluble or available P levels. Immature composts may have more soluble P than either manure or mature composts. Studies suggest that organic matter or acidic byproducts of composting may interfere with binding of P in soils and result in higher solution P. Addition of metal-containing byproducts to manures followed by composting suggests that metals can reduce soluble P levels almost immediately, but composting does not further reduce the soluble P in manures. Growth chamber studies demonstrate that composted poultry manure P is as available to the plant as triple superphosphate. Composting manures does not aid in reducing soluble P levels in manures, but still is a excellent method for stabilizing manures, reducing moisture content, reducing or eliminating animal and plant pathogens, and producing a product that is easily stored, easily mixed with ingredients, and applied to fields. Combining or blending manures with byproducts containing Al, Ca or Fe and composting would result in a product with highly desirable physical, biological and chemical characteristics to meet present-day guidelines for manure use.

University of Florida, Indian River Research and Education Center, 2199 S. Rock Rd., Fort Pierce, Florida 34945 USA

Nitrogen (N) mineralization kinetics of composts was evaluated under field conditions. Biosolids, yard waste, and biosolids/yardwaste composts were incubated for three months in a raised-bed, polyethylene covered vegetable and citrus cropping systems. Compost samples were packed into PVC columns (8 cm h and 5 cm dia) and inserted vertically into the upper layer of Oldsmar sand (sandy, siliceous, hyperthermic Alfic Arenic Haplaquods). The top of each column was capped to reduce leaching and volatilization loss of N and the bottom was fitted with a 400-mesh nylon screen to allow normal movement of water. A compost sample and a soil core (20 cm h and 6 cm diam) below each column were taken at 30 d intervals to measure the amount of N mineralized during this period. An accelerated release of total inorganic N (NH4-N and NO3-N) occured during the first 60 days and became slower at the later stage of the incubation. Among the kinetic models evaluated, the two constant rate model is the optimal for describing N mineralization from all the three composts under field conditions, followed by the Langmuir kinetic model. Nitrogen mineralization rates (%) ranged from 1.4 (yard waste) to 29 (biosolids), based on a KCl extraction estimation.