Closing the cycle for the cut rose industry by the reuse of its organic wastes: A case study in Ecuador

The soil conditions and the yield and quality of Rosa sp. var. Freedom were determined following the incorporation into the soil of rose waste composts, with or without fertigation; the effects of these treatments were compared with those of non-stabilised chopped rose wastes þ fertigation (FWF). The growing conditions were those of a commercial greenhouse. The use of the composts, alone or combined with fertigation, increased the available P and K contents of the soil with respect to FWF. However, only the compost þ fertigation treatments improved, in general, the soil fertility regarding the organic matter (OM), nitrogen and available micronutrient concentrations, in comparison to FWF. When the composts were added alone, irrigation with alkaline water increased the soil pH and, in consequence, reduced the availability of micronutrients. Overall, the combined use of compost and fertigation increased the cut rose yield and quality relative to the application of compost alone and FWF. Principal component analysis indicated that the OM, available Cu, Mn and Zn and total N contents and the pH of the soil were the principal soil parameters determining the yield and quality of the roses. This analysis classified the treatments in three groups: the compost þ fertigation treatments; the treatments with compost alone; and the FWF treatment. The compost þ fertigation treatments gave the highest net income (average for these treatments ¼ 80388.92 US dollars ha 1). Therefore, the compost þ fertigation treatments were highly beneficial with regard to increasing soil fertility and cut rose yield, quality and profitability

Characterization of Agro-Livestock Wastes for Composting in Rural Zones in Ecuador: The Case of the Parish of San Andrés

In Ecuador, the agriculture and livestock sectors are very important within the economy of rural areas. These activities generate a large amount of waste whose management is not optimized. Thus, the aim of this work was to characterize different agro-livestock wastes generated in a rural area, the parish of San Andrés (Chimborazo-Ecuador), in order to know their composition to design suitable composting processes for their treatment. To this end, different physicochemical and chemical parameters were determined in 24 crop residue samples and 18 manure samples, and two piles were elaborated with the same proportion of wastes (51% vegetable residue + 35% cow manure + 14% sawdust) and composted by turning or passive aeration. Throughout the composting process, the temperature and oxygen concentration were recorded and the evolution of different physicochemical, chemical, and biological parameters and the quality of the final composts were studied. The results indicated that the agro-livestock residues presented notable macro and micronutrient and organic matter contents and low levels of heavy metals, these properties being positive for their subsequent treatment in a co-composting experiment. This experiment demonstrated that the composting processes are a feasible strategy for the treatment of these residues and yield compost with an adequate agricultural quality (notable nitrogen content, low heavy metal and soluble mineral salt contents and 92–94% in germination index). Moreover, the passive aeration system can be recommended because this aeration method reduced composting times and the work associated with the process. However, more studies are required on this composting system and other agro-livestock wastes to establish a management protocol for all the waste generated, which will contribute to the sustainability of the agro-livestock sector in the area studie

Agronomic, Economic and Environmental Comparative of Different Aeration Systems for On-Farm Composting

On-farm composting of agro-livestock wastes can be considered the most appropriate method for their recycling. Pile turning (PW) is one of the most widely used aeration systems for composting. However, this system has long composting periods and is inefficient at supplying oxygen and controlling the temperature. To minimize these drawbacks, the combination of turnings with forced aeration (PR) is an option; in this work, this combination was compared to PW as an aeration system for the co-composting of vegetable waste with different manures. In this comparative study, the evolution of the process, the compost quality and the economic and environmental impacts of the process were evaluated. The PR system was more appropriate for obtaining sanitized composts (the temperature was ≥55 °C for at least three consecutive days) with an adequate degree of maturity. Furthermore, this system reduced the organic matter and nutrient losses, yielding composts with higher agronomic value and a higher total combined value of the nutrients than those obtained using the PW system. However, the energy consumption and associated CO2 emissions were lower for the PW system, since this aeration system was based only on turnings without the use of forced aeration, as in the case of the PR system. Agricultural valorization of composts will offset this energy consumption and its impact, since it will contribute to reducing the use of synthetic fertilizers. However, more studies are required on the PR composting system and other agro-livestock wastes for the creation of centralized on-farm composting sites, where all steps of the composting chain are optimize

Composting as a method to recycle renewable plant resources back tothe ornamental plant industry: Agronomic and economic assessmentof composts

tIn this experiment, three piles were elaborated with rose waste (RW), sawdust (S), and different manures– broiler chicken manure (BCM), hen manure (HM), and quail manure (QM) – and were composted bywindrow composting. Parameters associated with the degradation and humification of organic matter(OM) during composting and with the agronomic and economic value of the final composts were deter-mined. All piles had temperatures >55◦C for more than two weeks, ensuring compost sanitization. OMdegradation was greater and faster in the pile with QM. This pile had the lowest water-soluble polyphenolcontent. Principal component analysis indicated that the use of BCM augmented the OM humificationduring composting; this material also influenced the mineralization of the OM. In general, the compostsobtained presented an adequate level of stability and maturity and an absence of phytotoxicity, and therewere notable concentrations of OM and nutrients, especially nitrogen. In addition, all the composts hadan economic value when their nutrient contents were assessed. Phosphorus was the fertilization unitwith the greatest contribution to the total value of the composts. However, the use of BCM produced acompost with properties that made it more suitable as an organic amendment for rose growing