Tomatenplant wordt spijkerbroek
Trindade, L.M. - \ 2019
biobased economy - crop residues - hemp - miscanthus - clothing
More food, lower footprint : How circular food production contributes to efficiency in the food system
Scholten, M.C.T. - \ 2017
Wageningen : Wageningen University & Research
biobased economy - biobased chemistry - cycling - environment - sustainability - nutrition - biomass - renewable energy - residual streams - agricultural wastes - organic wastes - crop residues - food production - biobased economy - chemie op basis van biologische grondstoffen - kringlopen - milieu - duurzaamheid (sustainability) - voeding - biomassa - hernieuwbare energie - reststromen - agrarische afvalstoffen - organisch afval - oogstresten - voedselproductie
Martin Scholten on circular food production. Ideas about how circular food production can contribute to the sustainable food security.
Biogas production and digestate utilisation from agricultural residues : deliverable nº: 6.2.1
Corre, W.J. ; Conijn, J.G. - \ 2016
HYSOL project - 39
renewable energy - anaerobic digestion - biogas - crop residues - agricultural wastes - sustainable energy - electricity supplies - innovations - biobased economy - fermentation - digestate - hernieuwbare energie - anaërobe afbraak - biogas - oogstresten - agrarische afvalstoffen - duurzame energie - elektriciteitsvoorzieningen - innovaties - biobased economy - fermentatie - digestaat
The HYSOL project aims at hybridisation of concentrated solar power with a gas turbine in order to guarantee a stable and reliable electricity supply, based on renewable energy. The production of fully renewable electricity in a Hybrid Concentrated Solar Power (HCSP) plant includes the use of renewable gas. In task 6.2 of the HYSOL project research into the possibilities of sustainable biogas production from agricultural residues by anaerobic digestion has been performed. In this report results are described of part of this research focussing on potential biogas production and digestate production and utilisation from animal manure and crop residues.
Evaluatie tijdelijke regeling bijdragen onderwerken graanresten : Onderdeel onderzoek naar alternatieven
Visser, A.J. ; Spruijt, J. ; Timmer, R.D. ; Schotman, A.G.M. ; Dekking, A.J.G. ; Groten, J.A.M. ; Buij, R. ; Melman, T.C.P. - \ 2016
Wageningen Plant Research (Wageningen Plant Research rapport 720) - 43
graangewassen - graan - oogstresten - plantenresten - grain crops - grain - crop residues - plant residues
Methodology for estimating emissions from agriculture in the Netherlands. : Calculations of CH4, NH3, N2O, NOx, PM10, PM2.5 and CO2 with the National Emission Model for Agriculture (NEMA)
Vonk, J. ; Bannink, A. ; Bruggen, C. van; Groenestein, C.M. ; Huijsmans, J.F.M. ; Kolk, J.W.H. van der; Luesink, H.H. ; Oude Voshaar, S.V. ; Sluis, S.M. ; Velthof, G.L. - \ 2016
Wageningen : Statutory Research Tasks Unit for Nature & the Environment (WOt-technical report 53) - 164
air pollutants, greenhouse gases, livestock, crops, animal housing, manure storage, manure application, inorganic fertilizer, enteric fermentation, manure management, agricultural soils, liming, NIR, CRF, IIR, NFR - landbouw - gewassen - landbouwgronden - vee - huisvesting, dieren - dierlijke meststoffen - rundveemest - mestverwerking - begrazing - broeikasgassen - luchtverontreinigende stoffen - emissie - ammoniakemissie - kooldioxide - methaan - anorganische meststoffen - fermentatie - bekalking - nederland - compost - rioolslib - teelt - oogstresten - rijp worden - agriculture - crops - agricultural soils - livestock - animal housing - animal manures - cattle manure - manure treatment - grazing - greenhouse gases - air pollutants - emission - ammonia emission - carbon dioxide - methane - inorganic fertilizers - fermentation - liming - netherlands - composts - sewage sludge - cultivation - crop residues - ripening
The National Emission Model for Agriculture (NEMA) is used to calculate emissions to air from agricultural activities in the Netherlands on a national scale. Emissions of ammonia (NH3) and other N-compounds (NOx and N2O) from animal housing, manure storage, manure application and grazing are assessed using a Total Ammoniacal Nitrogen (TAN) flow model. Furthermore, emissions from application of inorganic N-fertilizer, compost and sewage sludge, cultivation of organic soils, crop residues, and ripening of crops are calculated. NEMA is also used to estimate emissions of methane (CH4) from enteric fermentation and manure management, particulate matter (PM) from manure management and agricultural soils, and carbon dioxide
(CO2) from liming. Emissions are calculated in accordance with international guidance criteria and reported in an annual Informative Inventory Report (IIR; for air pollutants) and National Inventory Report (NIR; for greenhouse gases). This methodology report describes the outline and backgrounds of the emission
calculations with NEMA
Understanding the impact and adoption of conservation agriculture in Africa: a multi-scale analysis
Corbeels, M. ; Graaff, J. de; Hycenth Ndah, T. ; Penot, E. ; Baudron, F. ; Naudin, K. ; Andrieu, N. ; Chirat, G. ; Schuler, J. ; Nyagumbo, I. ; Rusinamhodzi, L. ; Traore, K. ; Mzoba, H.D. ; Adolwa, I.S. - \ 2014
Agriculture, Ecosystems and Environment 187 (2014). - ISSN 0167-8809 - p. 155 - 170.
crop residues - soil quality - productivity - zimbabwe - maize - yield - intensification - tillage - poverty - systems
Conservation agriculture (CA) is increasingly promoted in Africa as an alternative for coping with the need to increase food production on the basis of more sustainable farming practices. Success with adopting CA on farms in Africa has been limited, despite more than two decades of research and development investments. Through analyzing past and on-going CA experiences in a set of case studies, this paper seeks to better understand the reasons for the limited adoption of CA and to assess where, when and for whom CA works best. CA is analyzed and understood within a framework that distinguishes the following scales of analysis: field, farm, village and region. CA has a potential to increase crop yields in the fields, especially under conditions of erratic rainfall and over the long-term as a result of a gradual increase of overall soil quality. The impact on farm income with the practice of CA on some fields of the farm is far less evident, and depends on the type of farm. The lack of an immediate increase in farm income with CA explains in many cases the non-adoption of CA. Smallholders have often short-term time horizons: future benefits do not adequately outweigh their immediate needs. Another key factor that explains the limited CA adoption in mixed crop-livestock farming systems is the fact that crop harvest residues are preferably used as fodder for livestock, preventing their use as soil cover. Finally, in most case studies good markets for purchase of inputs and sale of produce – a key prerequisite condition for adoption of new technologies – were lacking. The case studies show clear evidence for the need to target end users (not all farmers are potential end user of CA) and adapt CA systems to the local circumstances of the farmers, considering in particular the farmer's investment capacity in the practice of CA and the compatibility of CA with his/her production objectives and existing farming activities. The identification of situations where, when and for whom CA works will help future development agents to better target their investments with CA.
Role of maize stover incorporation on nitrogen oxide emissions in a non-irrigated Mediterranean barley field
Abalos, D. ; Sanz-Cobena, A. ; Garcia-Torres, L. ; Groenigen, J.W. van; Vallejo, A. - \ 2013
Plant and Soil 364 (2013)1-2. - ISSN 0032-079X - p. 357 - 371.
treated pig slurries - nitric-oxide - inorganic fertilizer - microbial biomass - plant residues - crop residues - soil - n2o - fluxes - denitrification
Agricultural soils in semiarid Mediterranean areas are characterized by low organic matter contents and low fertility levels. Application of crop residues and/or manures as amendments is a cost-effective and sustainable alternative to overcome this problem. However, these management practices may induce important changes in the nitrogen oxide emissions from these agroecosystems, with additional impacts on carbon dioxide emissions. In this context, a field experiment was carried out with a barley (Hordeum vulgare L.) crop under Mediterranean conditions to evaluate the effect of combining maize (Zea mays L.) residues and N fertilizer inputs (organic and/or mineral) on these emissions. Crop yield and N uptake, soil mineral N concentrations, dissolved organic carbon (DOC), denitrification capacity, N2O, NO and CO2 fluxes were measured during the growing season. The incorporation of maize stover increased N2O emissions during the experimental period by c. 105 %. Conversely, NO emissions were significantly reduced in the plots amended with crop residues. The partial substitution of urea by pig slurry reduced net N2O emissions by 46 and 39 %, with and without the incorporation of crop residues respectively. Net emissions of NO were reduced 38 and 17 % for the same treatments. Molar DOC:NO (3) (-) ratio was found to be a robust predictor of N2O and NO fluxes. The main effect of the interaction between crop residue and N fertilizer application occurred in the medium term (4-6 month after application), enhancing N2O emissions and decreasing NO emissions as consequence of residue incorporation. The substitution of urea by pig slurry can be considered a good management strategy since N2O and NO emissions were reduced by the use of the organic residue.
Availability of lignocellulosic feedstocks for lactic acid production - Feedstock availability, lactic acid production potential and selection criteria
Bakker, R.R.C. - \ 2013
Wageningen : Wageningen UR - Food & Biobased Research - 60
melkzuur - lignine - biomassa - oogstresten - beschikbaarheid - inventarisaties - biomassa productie - biobased economy - lactic acid - lignin - biomass - crop residues - availability - inventories - biomass production - biobased economy
The overall objective of this study is to assess the worldwide availability and suitability of agricultural residues for lactic acid production, based on fermentation of carbohydrates. The study focuses on lignocellulosic biomass that is produced as a by-product of agricultural production. The results of the study can be used to rank different biomass types on their lactic acid or fermentable sugar production potential. For each residue, both total production (ton of fermentable sugars per year) and productivity (fermentable sugars produced per ha of agricultural land) are considered. Furthermore, the production of non-fermentable residues (e.g. lignin) is included as well in the study. The study is concluded by series of recommendations on what factors to consider when choosing a suitable lignocellulosic feedstock for production of lactic acid, or for other fermentation processes. The results of this study can be used to further evaluate suitability, cost and sustainability of using agricultural residues as feedstock for fermentative production of lactic acid production, or other biochemical conversion processes.
Ammonia emission from standing crops and crop residues : contribution to total ammonia emission in the Netherlands
Ruijter, F.J. de; Huijsmans, J.F.M. ; Zanten, M.C. ; Asman, W.A.H. ; Pul, W.A.J. van - \ 2013
Wageningen : Plant Research International (Report / Plant Research International 535) - 82
gewassen - oogstresten - emissiereductie - ammoniakemissie - crops - crop residues - emission reduction - ammonia emission
Ammonia emission from standing crops and crop residues : contribution to total ammonia emission in the Netherlands
Biocontrol and population dynamics of Fusarium spp. on wheat stubble in Argentina
Palazzini, J.M. ; Groenenboom-de Haas, B.H. de; Torres, A.M. ; Köhl, J. ; Chulze, S.N. - \ 2013
Plant Pathology 62 (2013)4. - ISSN 0032-0862 - p. 859 - 866.
head blight - clonostachys-rosea - botrytis-cinerea - biological-control - gibberella-zeae - quantitative detection - gliocladium-roseum - fumonisin content - crop residues - grain
The biocontrol effect of Clonostachys rosea (strains 016 and 1457) on Fusarium graminearum, F. avenaceum, F. verticillioides, F. langsethiae, F. poae, F. sporotrichioides, F. culmorum and Microdochium nivale was evaluated on naturally infected wheat stalks exposed to field conditions for 180 days. Experiments were conducted at two locations in Argentina, Marcos Juarez and Río Cuarto. Antagonists were applied as conidial suspensions at two inoculum levels. Pathogens were quantified by TaqMan real-time qPCR. During the first year at Marcos Juarez, biocontrol was observed in one antagonist treatment for F. graminearum after 90 days (73% reduction) but after 180 days, the pathogen decreased to undetectable levels. During the second year, biocontrol was observed in three antagonist treatments for F. graminearum and F. avenaceum (68·3% and 98·9% DNA reduction, respectively, after 90 days). Fusarium verticillioides was not controlled at Marcos Juarez. At Río Cuarto, biocontrol effects were observed in several treatments at different intervals, with a mean DNA reduction of 88·7% for F. graminearum and F. avenaceum, and 100% reduction for F. verticillioides in two treatments after 180 days. Populations of F. avenaceum and F. verticillioides were stable; meanwhile, F. graminearum population levels varied during the first 90 days, and low levels were observed after 180 days. The other pathogens were not detected. The study showed that wheat stalks were important reservoirs for F. avenaceum and F. verticillioides populations but less favourable for F. graminearum survival. Clonostachys rosea (strain 1457) showed potential to reduce the Fusarium spp. on wheat stalks
Short term effects of bioenergy by-products on soil C and N dynamics, nutrient availability and biochemical properties
Galvez, A. ; Sinicco, T. ; Cayuela, M.L. ; Mingorance, M.D. ; Fornasier, F. ; Mondini, C. - \ 2012
Agriculture, Ecosystems and Environment 160 (2012). - ISSN 0167-8809 - p. 3 - 14.
nitrous-oxide emission - microbial biomass - enzyme-activities - crop residues - organic amendments - carbon - mineralization - management - decomposition - composts
The shift towards a biobased economy will probably trigger the application of bioenergy by-products to the soil as either amendments or fertilizers. However, limited research has been done to determine how this will influence C and N dynamics and soil functioning. The aim of this work was to investigate the effects of different bioenergy by-products on C and N mineralisation, nutrient availability and microbial content and activity of amended soil and compare them to other more commonly used organic amendments. Two agricultural soils were amended (0.5% w/w) with four different bioenergy by-products (anaerobic digestate, rapeseed meal, bioethanol residue, biochar) and three other commonly used organic amendments (sewage sludge and two composts) and incubated at 20 degrees C in the laboratory for 30 days. During incubation, soil CO2 and N2O evolution were measured every 4 h by an automatic chromatographic system. After 2, 7 and 30 days of incubation, soil samples were analysed for K2SO4-extractable C, N, NO3-, NH4+ and P, microbial biomass C and three enzymatic activities (beta-glucosidase, alkaline phosphatase and leucine aminopeptidase). Soil amendment led to a general increase in soil respiration, available N and P and microbial content and activity, but with remarkably different dynamics and values. Particularly, rapeseed meal and the bioethanol by-product led to N2O emissions and the greatest increases in soil respiration, N availability and enzymatic activity compared with the other amendments. The exception was represented by biochar that did not cause any significant variation with respect to the control, but promoted C accumulation. According to their impact on soil biochemical properties, the materials can be ranked as follows: rapeseed meal, bioethanol residue > anaerobic digestate, sewage sludge > composts > biochar. For each measured parameter, soil properties did not affect the response pattern found for the different treatments, but modified the magnitude of the response. In particular, soil respiration and enzymatic activity were higher in the slightly acidic soil, while greater values of available P were found in the alkaline soil. This study clearly indicates that the impact on GHG emissions and soil functioning of bioenergy byproducts needs to be taken into account for a correct life cycle assessment of the bioenergy chain. Moreover, when properly managed, they may represent an effective alternative to usual amendments to improve the quality and nutrient balance of amended soils.
Residue incorporation depth is a controlling factor of earthworm-induced nitrous oxide emissions
Paul, B.K. ; Lubbers, I.M. ; Groenigen, J.W. van - \ 2012
Global Change Biology 18 (2012)3. - ISSN 1354-1013 - p. 1141 - 1151.
organic-matter dynamics - filled pore-space - lumbricus-terrestris - n2o emissions - nitrifier denitrification - ecosystem engineers - microbial activity - n mineralization - crop residues - soil carbon
Earthworms can increase nitrous oxide (N2O) emissions, particularly in no-tillage systems where earthworms are abundant. Here, we study the effect of residue incorporation depth on earthworm-induced N2O emissions. We hypothesized that cumulative N2O emissions decrease with residue incorporation depth, because (i) increased water filled pore space (WFPS) in deeper soil layers leads to higher denitrification rates as well as more complete denitrification; and (ii) the longer upward diffusion path increases N2O reduction to N2. Two 84-day laboratory mesocosm experiments were conducted. First, we manually incorporated maize (Zea maysL.) residue at different soil depths (incorporation experiment). Second, 13C-enriched maize residue was applied to the soil surface and anecic species Lumbricus terrestris (L.) and epigeic species Lumbricus rubellus (Hoffmeister) were confined to different soil depths (earthworm experiment). Residue incorporation depth affected cumulative N2O emissions in both experiments (P <0.001). In the incorporation experiment, N2O emissions decreased from 4.91 mg N2O–N kg-1 soil (surface application) to 2.71 mg N2O–N kg-1 soil (40–50 cm incorporation). In the earthworm experiment, N2O emissions from L. terrestris decreased from 3.87 mg N2O–N kg-1 soil (confined to 0–10 cm) to 2.01 mg N2O–N kg-1 soil (confined to 0–30 cm). Both experimental setups resulted in dissimilar WFPS profiles that affected N2O dynamics. We also found significant differences in residue C recovery in soil organic matter between L. terrestris (28–41%) and L. rubellus (56%). We conclude that (i) N2O emissions decrease with residue incorporation depth, although this effect was complicated by dissimilar WFPS profiles; and (ii) larger residue C incorporation by L. rubellus than L. terrestris indicates that earthworm species differ in their C stabilization potential. Our findings underline the importance of studying earthworm diversity in the context of greenhouse gas emissions from agro-ecosystems.
Bioenergy from cattle manure? Implications of anaerobic digestion and subsequent pyrolysis for carbon and nitrogen dynamics in soil
Schouten, S. ; Groenigen, J.W. van; Oenema, O. ; Cayuela, M.L. - \ 2012
Global change biology Bioenergy 4 (2012)6. - ISSN 1757-1693 - p. 751 - 760.
greenhouse-gas emissions - black carbon - organic-matter - microbial biomass - slurry treatment - oxide emission - crop residues - by-products - pig slurry - biochar
Cattle manure can be processed to produce bioenergy, resulting in by-products with different physicochemical characteristics. To evaluate whether application of such bioenergy by-products to soils would be beneficial compared with their unprocessed counterpart, we quantified differences in greenhouse gas emissions and carbon (C) and nitrogen (N) dynamics in soil. Three by-products (15N-labeled cattle manure, from which anaerobic digestate was obtained, which was subsequently pyrolysed) were applied to a loess and a sandy soil in a laboratory incubation study. The highest losses of soil C from biological activity (CO2 respiration) were observed in manure treatments (39% and 32% for loess and sandy soil), followed by digestate (31% and and 18%), and biochar (15% and and 7%). Emissions of nitrous oxide (N2O) ranged from 0.6% of applied N from biochar to 4.0% from manure. Isotope labeling indicated that manure N was most readily mineralized, contributing 50% to soil inorganic N. The anaerobic digestate was the only by-product increasing the mineral N pool, while reducing emissions of N2O compared with manure. In biochar treatments, less than 18.3% of soil mineral N derived from the biochar, while it did not constrain mineralization of native soil N. By-products of anaerobic digestion and pyrolysis revealed soil fertility in addition to environmental benefits. However, the reported advantages lessen when the declining yields of C and N over the bioenergy chain are considered.
Ammonia emission from crop residues : quantification of ammonia volatilization based on crop residue properties
Ruijter, F.J. de; Huijsmans, J.F.M. - \ 2012
Wageningen : Plant Research International (Report / Plant Research International 470) - 30
oogstresten - oogstresten als veevoer - ammoniak - vervluchtiging - nederland - degradatie - akkerbouw - ammoniakemissie - crop residues - stover - ammonia - volatilization - netherlands - degradation - arable farming - ammonia emission
This paper gives an overview of available literature data on ammonia volatilization from crop residues. From these data, a relation is derived for the ammonia emission depending on the N-content of crop residue.
Fungal strain and incubation period affect chemical composition and nutrient availability of wheat straw for rumen fermentation
Tuyen, Van Dinh ; Cone, J.W. ; Baars, J.J.P. ; Sonnenberg, A.S.M. ; Hendriks, W.H. - \ 2012
Bioresource Technology 111 (2012). - ISSN 0960-8524 - p. 336 - 342.
white-rot fungi - solid-state fermentation - in-vitro digestibility - pleurotus-ostreatus - ceriporiopsis-subvermispora - trametes-versicolor - sugarcane bagasse - detergent fiber - crop residues - animal feed
Eleven white-rot fungi were examined for their potency to degrade lignin and to improve the rumen fermentability of wheat straw. The straw was inoculated with the fungi and incubated under solid state conditions at 24 °C for 0–49 days to determine changes in in vitro gas production and chemical composition. Results show that some fungi could degrade lignin by as much as 63%, yet the delignification was highly correlated with the degradation of hemicellulose (r = 0.96). Reduction in lignin was poorly (r = 0.47), but the ratio between lignin and cellulose loss was strongly (r = 0.87) correlated with the increase in gas production. Treatment with Ceriporiopsis subvermispora for 49 days increased total gas production of the straw from 200 to 309 ml/g organic matter (OM). It was concluded that some fungi highly selective for lignin and not for cellulose are able to improve the nutritive value of wheat straw as a ruminant feed
Differentiation of nitrous oxide emission factors for agricultural soils
Lesschen, J.P. ; Velthof, G.L. ; Vries, W. de; Kros, J. - \ 2011
Environmental Pollution 159 (2011)11. - ISSN 0269-7491 - p. 3215 - 3222.
volatile fatty-acids - n2o emissions - cattle slurry - crop residues - fertilizer application - grassland soil - animal manures - gas emissions - water-content - barley field
Nitrous oxide (N2O) direct soil emissions from agriculture are often estimated using the default IPCC emission factor (EF) of 1%. However, a large variation in EFs exists due to differences in environment, crops and management. We developed an approach to determine N2O EFs that depend on N-input sources and environmental factors. The starting point of the method was a monitoring study in which an EF of 1% was found. The conditions of this experiment were set as the reference from which the effects of 16 sources of N input, three soil types, two land-use types and annual precipitation on the N2O EF were estimated. The derived EF inference scheme performed on average better than the default IPCC EF. The use of differentiated EFs, including different regional conditions, allows accounting for the effects of more mitigation measures and offers European countries a possibility to use a Tier 2 approach
Predicting soil nitrogen supply : relevance of extractable soil organic matter fractions
Ros, G.H. - \ 2011
Wageningen University. Promotor(en): Willem van Riemsdijk, co-promotor(en): Erwin Temminghoff; Ellis Hoffland. - [S.l.] : S.n. - ISBN 9789085858829 - 243
mineralisatie - organische stikstof - bodem - organisch bodemmateriaal - bodemonderzoek - voorspelling - bodemtestwaarden - beoordeling - oogstresten - mineralization - organic nitrogen - soil - soil organic matter - soil testing - prediction - soil test values - assessment - crop residues
Predicting the potential of soils to supply N is of considerable importance to maximize agricultural N use efficiency and to minimize environmental losses. This research examines and evaluates the current soil testing approach, which uses extractable organic N (EON) fractions to predict soil N supply, using isotopic 15N tracing, multivariate statistics and meta-analytical techniques.
Bepalingsmethoden percentage oogstrestanten van uien in tarragrond
Brink, L. van den - \ 2010
Lelystad : PPO AGV - 23
akkerbouw - uien - tarra - bodemmonitoring - oogstresten - landbouwproducten - meting - bepaling - arable farming - onions - tare - soil monitoring - crop residues - agricultural products - measurement - determination
Resultaten van onderzoek naar het ontwikkelen van een methode voor het bepalen van het percentage oogstrestanten van uien in tarragrond in de gemeente Borsele.
Afval uit de landbouw
Bondt, N. ; Janssens, S.R.M. ; Smet, A. de - \ 2010
Den Haag : LEI Wageningen UR (LEI-nota 10-061) - 22
landbouw - tuinbouw - oogstresten - afvalbeheer - organisch afval - agrarische afvalstoffen - duurzaamheid (sustainability) - plantenresten - afvalverwerking - modellen - overzichten - agriculture - horticulture - crop residues - waste management - organic wastes - agricultural wastes - sustainability - plant residues - waste treatment - models - reviews
In dit onderzoek zijn voor verschillende sectoren afvalstromen in beeld gebracht: akkerbouw, vollegrondsgroenten, bloembollen, boomkwekerij, fruittteelt, paddestoelen, glastuinbouw en agrarisch natuurbeheer. Dit onderzoek richt zich op afvalstromen gerelateerd aan de organische teelt. Niet alle afvalstromen zijn in het model opgenomen zoals gevaarlijk afval of afvalstromen die ontstaan als gevolg van incidentele omstandigheden en dierlijke mest.
Nitrous oxide and carbon dioxide emissions during initial decomposition of animal by-products applied as fertilisers to soils.
Cayuela, M.L. ; Velthof, G.L. ; Mondini, C. ; Sinicco, T. ; Groenigen, J.W. van - \ 2010
Geoderma 157 (2010)3-4. - ISSN 0016-7061 - p. 235 - 242.
greenhouse-gas emissions - bone meal - mineralization dynamics - crop residues - n2o - amendments - ratios - plant
The recycling of organic wastes as soil amendments is notably promoted in sustainable agricultural systems. However, for many animal by-products approved by organic farming regulations little is known about their effects on the greenhouse gas balance of the soil, in particular on N2O emissions. In this work we report on the N2O and CO2 emissions from six animal-derived wastes (horn and hoof meal, blood meal, hydrolysed leather, meat bone meal, chicken manure and a commercial organic mixed fertiliser). We compared these emissions to those from a mineral fertiliser (calcium ammonium nitrate) in a sandy and a loam soil during a three month laboratory incubation study. N2O flux dynamics varied strongly with residue category and soil type. In the sandy soil, cumulative N2O emissions correlated with soil NO3- content. Although the mineral fertiliser produced the highest total N2O emissions (5.7 mg N2O–N kg- 1 soil), the commercial organic fertiliser mixture led to statistically similar emissions (5.3 mg N2O–N kg- 1 soil). The other by-products emitted between 1.3–3.0 mg N2O–N kg- 1 soil, and only blood meal emitted less than 1 mg N2O–N kg- 1 soil. In the loam soil, N2O emissions never exceeded 1.0 mg N2O–N kg- 1 soil, and did not correlate with NO3- in soil. With regard to CO2 emissions and C storage potential, chicken manure was the only residue that significantly accumulated C in both soils during the course of our experiment. The addition of an extra easily available source of C (glucose) or N (NO3-) influenced N2O emissions differently depending on the residue applied. Our results showed that despite the extra amount of C added with the organic amendments, N2O emissions from animal-derived wastes were never higher than those from the mineral fertiliser