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Currently, the management of urban waste streams in developing countries is not optimized yet, and in many cases these wastes are disposed untreated in open dumps. This fact causes serious environmental and health problems due to the presence of contaminants and pathogens. Frequently, the use of specific low-cost strategies reduces the total amount of wastes. These strategies are mainly associated to the identification, separate collection and composting of specific organic waste streams, such as vegetable and fruit refuses from food markets and urban gardening activities. Concretely, in the Chimborazo Region (Ecuador), more than 80% of municipal solid waste is dumped into environment due to the lack of an efficient waste management strategy. Therefore, the aim of this study was to develop a demonstration project at field scale in this region to evaluate the feasibility of implanting the composting technology not only for the management of the organic waste fluxes from food market and gardening activities to be scaled-up in other developing regions, but also to obtain an end-product with a commercial value as organic fertilizer. Three co-composting mixtures were prepared using market wastes mixed with pruning of trees and ornamental palms as bulking agents. Two piles were created using different proportions of market waste and prunings of trees and ornamental palms: pile 1 (50:33:17) with a C/N ratio 25; pile 2: (60:30:10) with C/N ratio 24 and pile 3 (75:0:25) with C/N ratio 33), prepared with market waste and prunings of ornamental palm. Throughout the process, the temperature of the mixtures was monitored and organic matter evolution was determined using thermogravimetric and chemical techniques. Additionally, physico-chemical, chemical and agronomic parameters were determined to evaluate compost quality. The results obtained indicated that all the piles showed a suitable development of the composting process, with a significant organic matter decomposition, reached in a shorter period of time in pile 3. At the end of the process, all the composts showed absence of phytotoxicity and suitable agronomic properties for their use as organic fertilizers. This reflects the viability of the proposed alternative to be scaled-up in developing areas, not only to manage and recycle urban waste fluxes, but also to obtain organic fertilizers, including added value in economic terms related to nutrient contents.

This work was conducted in order to investigate the possibility of using different agroindustrial composts in the production of horticultural seedlings, thereby replacing part of the peat in the growing media. Three vegetable species differing in salt sensitivity - tomato (Solanum lycopersicum L. var. Malpica) (the least sensitive), courgette (Cucurbita pepo L. var. Mastil F1) (moderately sensitive) and pepper (Capsicum annuum L. var. Largo de Reus Pairal) (the most sensitive) - were grown in nine media containing three composts, prepared by co-composting vegetable waste (flower, broccoli or tomato waste) with laying hen manure and sawdust, as well as peat in various ratios. The proportions of the three composts in the mixtures elaborated with peat were 25%, 50% and 75% (v/v). A substrate of 100% peat was used as control. The experiment was arranged in a completely-randomised design, with two replicates per treatment, under greenhouse conditions. Prior to sowing, some physical, physico-chemical and chemical properties of the growing media were determined and the seed germination and fresh and dry weights of the aerial parts and roots of the seedlings were also measured, as well as the mineral composition of the aerial parts of the plants. In most cases, the addition of compost to the growing media produced an increase in the pH, salt content and macronutrient concentrations, in comparison to peat, whereas the physical properties of the compost based-substrates had values very similar to those of an ideal substrate. Also, multivariate analysis showed that the media prepared with flower waste compost, at all concentrations, and the medium with tomato waste compost at 25% were the most suitable substrates for the three plant species tested., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

We have used an integrated approach to study the mobility of inorganic phosphorus (P) from soil solid phase as well as the microbial biomass P and respiration at increasing doses of citric and oxalic acid in two different soils with contrasting agronomic P status. Citric or oxalic acids significantly increased soil solution P concentrations for doses over 2 mmol kg -1 . However, low organic acid doses (<2 mmol kg -1 ) were associated with a steep increase in microbial biomass P, which was not seen for higher doses. In both soils, treatment with the tribasic citric acid led to a greater increase in soil solution P than the dibasic oxalic acid, likely due to the rapid degrading of oxalic acids in soils. After equilibration of soils with citric or oxalic acids, the adsorbed-to-solution distribution coefficient (K d ) and desorption rate constants (k -1 ) decreased whereas an increase in the response time of solution P equilibration (T c ) was observed. The extent of this effect was shown to be both soil and organic acid specific. Our results illustrate the critical thresholds of organic acid concentration necessary to mobilize sorbed and precipitated P, bringing new insight on how the exudation of organic acids regulate chemical-microbial soil phosphorus transformations.

In Ecuador, enormous quantities of vegetable wastes are produced annually from the horticultural industries. Composting can be a feasible treatment to stabilise horticultural wastes and, thus, to improve their properties for use as organic fertilisers. In this study, two different piles were prepared, using laying hen manure and sawdust mixed with broccoli or tomato waste, respectively, and composted by the turned windrow composting system. Throughout the composting process, the temperature of the mixtures was monitored and physico-chemical and chemical properties and the degree of maturity were determined. Also, principal component analysis was used to interpret the data set of compost characteristics. In both piles, the temperature exceeded 55°C for more than 2weeks, which ensured maximum pathogen reduction. Organic matter (OM) losses followed a first-order kinetic equation in both piles. The final composts showed a suitable degree of stability and maturity and an absence of phytotoxins, as observed in the evolution and final values of the total organic carbon/total nitrogen ratio (Corg/NT<20), water-soluble organic carbon (Cw<1.7%), germination index (GI>50%) and cation exchange capacity (CEC>67meq (100g OM)(-1)). As well, the evolution of different humification indexes during composting was a good indicator of the OM humification process. The type of vegetable waste used influenced OM and NT mineralisation and the final properties of the composts, showing the mixture with tomato waste a higher fertilising capacity and less environmental problems., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The objective of this work was to study the co-composting process of wastes from the winery and distillery industry with animal manures, using the classical chemical methods traditionally used in composting studies together with advanced instrumental methods (thermal analysis, FT-IR and CPMAS 13C NMR techniques), to evaluate the development of the process and the quality of the end-products obtained. For this, three piles were elaborated by the turning composting system, using as raw materials winery-distillery wastes (grape marc and exhausted grape marc) and animal manures (cattle manure and poultry manure). The classical analytical methods showed a suitable development of the process in all the piles, but these techniques were ineffective to study the humification process during the composting of this type of materials. However, their combination with the advanced instrumental techniques clearly provided more information regarding the turnover of the organic matter pools during the composting process of these materials. Thermal analysis allowed to estimate the degradability of the remaining material and to assess qualitatively the rate of OM stabilization and recalcitrant C in the compost samples, based on the energy required to achieve the same mass losses. FT-IR spectra mainly showed variations between piles and time of sampling in the bands associated to complex organic compounds (mainly at 1420 and 1540 cm-1) and to nitrate and inorganic components (at 875 and 1384 cm-1, respectively), indicating composted material stability and maturity; while CPMAS 13C NMR provided semi-quantitatively partition of C compounds and structures during the process, being especially interesting their variation to evaluate the biotransformation of each C pool, especially in the comparison of recalcitrant C vs labile C pools, such as Alkyl /O-Alkyl ratio.

The application of organic materials to replenish soil organic matter and improve soil structure and fertility has become a common agronomic practice. This research deals with the effects of soil amendment with winery and distillery waste composts on organic carbon (C) mineralisation in two arable soils. A sandy-loam and clay-loam soil were treated and incubated with a number organic materials obtained from the co-composting of different proportions of grape stalk, grape marc, exhausted grape marc and vinasse, with sewage sludge or animal manure. Moreover, the effect of compost stability on C mineralisation dynamics was studied by applying organic materials from different stages of the composting process. The results obtained showed that the addition of exogenous organic matter stimulated microbial growth, enhanced soil respiration and increased water-extractable C contents in both soils, particularly in the days immediately following amendment. The initial composition of the different organic materials used, especially for the mature samples, and the texture of the receiving soil did not influence significantly the C mineralisation final values, with around 11-20% of the added organic C being mineralised over the first 140 days. However, the contribution of organic amendment to the labile organic C pool, maximum rates of soil respiration, as well as the extent of initial disturbance of the soil microbiota were all found to be related to the degree of organic matter stability. Moreover, irrespective of the type and stability of the organic amendment, the mineralogical composition of the receiving soil was found to significantly influence its resilience in such systems., ((c) 2010 Elsevier Ltd. All rights reserved.)

Physico-chemical, chemical and microbiological parameters were studied in a set of fifteen different composts elaborated with agroindustrial wastes using two different composting systems (turning and static pile composting). To carry out the chemometric evaluation, multivariate statistical analysis techniques, such as hierarchical cluster analysis (HCA) and factorial analysis (FA) were used. Composts obtained showed suitable physico-chemical and chemical properties for their use as organic amendment and a good maturity degree. HCA allowed to classify the organic materials mainly in four groups: cluster A, cluster B, cluster C and unclustered composts; also, this statistical tool showed the lack of influence of the composting system in the final characteristics of these composts. On the other hand, through FA, it was possible to identify the principal variables associated to the composting of agroindustrial wastes in four factors that explained 72.3% of the variability., (Copyright 2010 Elsevier Ltd. All rights reserved.)

The content and chemical forms of P in compost are essential variables for its proper management with an agricultural purpose, especially considering the increasing P over-fertilization in agrosystems. In this study, the estimation of P content and dynamics in different composting scenarios was developed using near infrared reflectance spectroscopy (NIRS) coupled with a statistical tool for calibration, a penalized signal regression. Samples were analyzed on total P and partitioned using NaOH-solution (31)P NMR spectroscopy quantifying pyrophosphate, orthophosphate, orthophosphate diesters, phospholipids, and orthophosphate monoesters pools. According to the results obtained, total P content (r(2)=0.99 and root mean square error of cross-validation=0.53) and P forms can be estimated during composting using NIRS, as well as in the mature product, orthophosphate and orthophosphate monoesters being the most abundant P forms throughout the experiment. Penalized signal regression allows detecting the significant wavenumbers in each composting period, and also with the different P pools in the composting pile depending on time.

The intensification in livestock production has increased the need of efficient treatments of waste streams especially to preserve as much as possible, the nutrients into the soil-plant system. Composting is a cheap, efficient and sustainable treatment for solid wastes that is always included in any manure treatment scenario. In this paper, an overview about the environmental and safety challenges of composting of manures is made considering the compost quality requirements established by the main demanding sectors. Co-composting and additive strategies are presented as feasible options for the improvement of compost quality. For quality evaluation of manure compost, the use of both classical and innovative instrumental techniques could increase our knowledge about added properties in compost, especially those related to organic matter stability.

The aim of the present paper is to evaluate the changes of organic matter during the composting process of fresh winery and distillery residues (WDR) by means of classical and chemometric analysis of (13)C cross-polarization magic angle spinning (CPMAS) NMR and Fourier transform infrared (FT-IR) spectra. (13)C NMR spectroscopy displayed a preferential biodegradation of carbohydrates as well as an accumulation of aliphatic chains (cutin- and suberin-like substances). This preferential biodegradation of the organic fractions reduces the landfill emission potential. Although the composition of the input mixture strongly affects the shape of the infrared (IR) spectra, typical bands of components can be selected and used to follow the composting process; that is, changes in the relative absorbances of the band of nitrate (at 1384 cm(-1)) and in the band of carbohydrates (at 1037 cm(-1)) have been observed. In addition, different chemometric tools, such as partial least-squares (PLS), interval PLS (iPLS), backward iPLS (biPLS), and genetic algorithm (GA), have been used to find the most relevant spectral region during the composting process. Chemometric analysis based on the combined and sequential use of iPLS and GA has been revealed as a very powerful tool for the detection in samples of the most relevant spectral region related to the composting process. From the obtained results, it can be concluded that CPMAS (13)C NMR supported by FT-IR could provide information about the evolution and characteristics of the organic matter during the composting process in order to avoid contamination problems after its use as amendment in agriculture or after landfilling.

Physico-chemical, chemical and biological parameters were studied throughout the composting process of four winery and distillery composts and the data set of compost characteristics was analysed using multivariate techniques: factorial analysis (FA) and linear discriminant analysis (LDA), in order to classify the different parameters studied and thus, to establish those that better describe the composting process of this type of wastes. Through factorial analysis (FA) of the parameters studied throughout the composting process, four components that explained 85.6% of the variability were established. The parameters associated to compost maturity, agronomic character, water-soluble fraction and ammonia and temperature increment were grouped in the components F1, F2, F3 and F4, respectively, which can reduce the number of determinations needed to ascertain the maturity and quality of the composts. In addition, the linear discriminant analysis on the factorial components makes possible to classify the four composts with a percentage of success around 95%.

The aim of this study was to monitor some microbial indicators and pathogen contents (sulphite reducers clostridia, total enterobacteriaceae, total coliforms, faecal coliforms (Escherichia coli), enterococci, Staphylococcus aureus and Salmonella spp.) throughout the co-composting of wastes from the winery and distillery industry with other organic residues, as well as the effect of the composting system used. Seven different piles using mixtures of winery-distillery wastes with other organic materials were prepared. P1 and P2 were made using grape stalk (GS), grape marc (GM), exhausted grape marc (EGM) and sewage sludge (SS), whereas in P3 and P4 were also used exhausted grape marc with cow manure (CW) and poultry manure (PM), respectively, using the Rutgers system. Additionally, P2 was watered with vinasse (V). The rest of piles (P5, P6 and P7) were prepared with grape marc, exhausted grape marc, cow manure and poultry manure, using the turning system. The effectiveness of the composting process to reduce the pathogen content was higher in the static aerated piles than in those elaborated with the turning. The relatively high temperatures (50-60 degrees C) reached in some of the piles produced a notable decrease in some microbial groups, such as total and faecal coliforms (E. coli), but the characteristics of the raw materials used notably influenced the pathogen contents of the end-product.

The aim of this work was to study the viability of recycling the solid wastes generated by the winery and distillery industry by means of co-composting with animal manures, as well as to evaluate the quality of the composts obtained. Two piles, using exhausted grape marc and cattle manure or poultry manure, respectively (at ratios, on a fresh weight basis, of 70:30), were composted by the Rutgers static pile composting system. Throughout the composting process, a number of parameters were monitored, such as pH, electrical conductivity, organic matter, water-soluble carbon, water-soluble polyphenols, different forms of nitrogen (organic nitrogen, ammonium and nitrate) and humification indices (humification ratio, humification index, percentage of humic acid-like C, polymerisation ratio and cation exchange capacity), as well as the germination index. Organic matter losses followed first-order kinetics equation in both piles, the highest organic matter mineralisation rate being observed with exhausted grape marc and cow manure. On the other hand, the mixture with the lowest C/N ratio, using exhausted grape marc and poultry manure, showed the highest initial ammonium contents, probably due to the higher and more labile N content of poultry manure. The increase in the cation exchange capacity revealed the organic matter humification during composting. In contrast, other humification parameters, such as the humification ratio and the humification index, did not show the expected evolution and, thus, could not be used to assess compost maturity. Composting produced a degradation of the phytotoxic compounds, such as polyphenols, to give composts without a phytotoxic character. Therefore, composting can be considered as an efficient treatment to recycle this type of wastes, due to composts presented a stable and humified organic matter and without phytotoxic effects, which makes them suitable for their agronomic use.

The aim of this work was to study the influence of the organic wastes derived from the winery and distillery industry (grape stalk (GS), grape marc (GM), wine lees (WL) and exhausted grape marc (EG)) and the soil type (clayey-loam (S1), loam (S2) and sandy textured (S3)) on different soil characteristics, especially the carbon and nitrogen mineralisation. The evolution of C mineralisation fitted a first-order kinetic for all amended soils. An initial increase was observed in the specific respiration (qCO(2)) at the beginning of the experiment. However, afterwards, the evolution in the qCO(2) was to tend towards the values of the control soil due to the pattern of the soil to recover its initial equilibrium status. The addition of these materials in the soils produced a slight increase of the inorganic nitrogen content, except in the case of GS and EG in most of the studied soils. The use of GS as amendment produced an inhibition in the N mineralisation in the three types of soils studied. Organic matter mineralisation was probably influenced by soil type, the sandy soil favouring more the N and C mineralisation processes than the clayey-loam and loam soils.

The aim of the present paper is to assess the maturity degree reached by different samples of several mixtures from winery and distillery residues composted using the Rutgers composting system, by means of excitation-emission matrix (EEM) fluorescence spectroscopy. The composts were sampled once a week for about 200d. EEM spectra indicate the presence of different fluorophores. The fluorescence intensities of these peaks show trends related to the maturity of the composting samples selected. The "contour density" of EEM maps is strongly modified through time. We have used the quantitative method of fluorescence regional integration (FRI). The EEMs were delineated into five excitation-emission regions. The degree of compost maturity could be correlated with the percentage of the volumetric integration under the EEM within each region. Further refinement of these techniques should provide a relatively rapid method for assessing the suitability of the compost to soil application.

Abstract: The aim of this experiment was to study the effect of the application of pig slurry on potential pathogen (total and faecal coliform bacteria) presence in a Typic Xerofluvent soil. The experiment was conducted in field conditions, in the Segura River valley in the South East of Spain. Four treatments, in a fully-randomised design with three replicates per treatment, were established in experimental plots of 16 m2 each. Fertiliser treatments were: MF, mineral fertiliser (with a complex 16N–16P2O5–16K2O) equivalent to 150 kg N ha−1; PSF, organic fertilisation with swine manure slurry, at two different rates (supplying 150 and 210 kg N ha−1), and C, a controlled treatment without fertilisation. A high variability of the concentrations of total and faecal coliforms was observed during the experiment, mainly depends on the time and the treatment. The pig slurry amendment induced the highest initial and also persistent presence of total and faecal coliform bacteria. The higher application rate seemed to induce a long-lasting persistence of the total, but especially the faecal coliform, population in the amended soils compared to the lower rate. In most cases, an increase in the total coliforms content was observed in the soils amended with mineral fertiliser compared to controlled soils, probably due to an increase in soil microorganisms populations. In general, the total coliform bacteria was 2–3 log10 units higher than the faecal ones. Mostly, a tendency to decrease with time was observed in both indicator microorganisms, in all the treatments. [Copyright &y& Elsevier]