Biowaste and vegetable waste compost application to agriculture

The landfilling of biodegradable waste is proven to contribute to environmental degradation. Compost use in agriculture is increasing as both an alternative to landfilling for the management of biodegradable waste, as well as means of increasing or preserving soil organic matter. This research aimed to contribute to the identification of a system for managing the utilization of vegetable waste (agricultural plant-tissue waste) and biowaste (source-separated biodegradable municipal solid waste) composts for sustainable agriculture, with particular regards to nitrogen availability and leaching.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Soil quality characteristics of traditional agroforestry systems in Mouzaki area, central Greece

Agroforestry systems (AFS) are characterized by growing trees and crops on the same area, aiming at sustainable production and better natural resources management, whilst potentially contributing to climate change mitigation. One of the most important benefits related to the productivity of AFS is the maintenance or improvement of soil quality. In the present study, qualitative characteristics of soils were evaluated in eight traditional smallholder AFS in the Municipality of Mouzaki, central Greece. The AFS were both silvoarable and silvopastoral systems and they were located either in lowland or semi-mountainous areas. Within the research areas, the effect of the trees on soil parameters was investigated. Soil samples were collected at two depths (0–30 and 30–60 cm) and at three distances from the tree base, corresponding to half, twice, triple or quadruple the tree canopy width. Soil organic matter (OM), total N, available P, exchangeable K, electrical conductivity (ECe), cation exchange capacity, pH and bulk density were determined. The effects of altitude and land use (agroforestry practice) on the soil quality parameters were also evaluated. Soil quality characteristics varied among the eight AFS. The distance from the tree significantly affected only ECe (p = 0.042), which decreased from a mean value of 0.31 dS/m to 0.25 dS/m, as the distance from the tree increased. Silvoarable systems presented significantly higher pH, ECe, available P (p < 0.001) and total N (p = 0.012) content than silvopastoral. Increased altitude resulted in significantly higher levels of OM and total N within the top 30 cm depths (p < 0.001); mean soil OM was 1.7% and total N 0.11% in the AFS in the lowland, whereas in the semi-mountainous areas 2.4% and 0.16%, respectively. The results of the research provided evidence of soil carbon sequestration, thus indicating the potential of AFS to mitigate climate change. © 2022, The Author(s), under exclusive licence to Springer Nature B.V

ScienceDirect Agricultural use of microfiltered olive mill wastewater: effects on maize production and soil properties

Abstract The disposal of olive mill wastewater (OMWW) is considered as one of the most serious environmental problems in the Mediterranean region. This study constitutes part of a holistic OMWW management approach aiming at the production of high added value products from OMWW with zero discharge. OMWW constitutes an organic material that could be recycled back to the soil after its treatment with microfiltration, and used as liquid fertilizer for plant production, thus leading to an environmentally friendly cultivation method with minor carbon footprint, since wastewater would (partially or fully) substitute mineral fertilizers, fresh water savings, and also economic benefits to the farmer. Microfiltered OMWW (MF-OMWW) was applied to maize cultivation in a clay loam soil using two rates of 25 and 50 Mg ha -1 , with the addition of mineral fertilization of 200 kg N ha -1 . Furthermore, a treatment of only MF-OMWW applied at the rates of 50 Mg ha -1 and an only mineral fertilization treatment were used. The four treatments were replicated four times. The results of the 1 st year experiment showed that the different amounts of MF-OMWW used had no significant effect on soil properties. Maize yield, kernel moisture and fat content were not significantly influenced by the different treatments, whereas kernel protein, starch, fiber and ash content were significantly affected. Considering all quality and quantity parameters studied, the treatment with only mineral fertilizer N application gave similar results with the only MF-OMWW treatment, indicating the potential of mineral fertilizer full substitution by MF-OMWW, under the conditions of our study

Assessment and Modelling of Groundwater Quality Data by Environmetric Methods in the Context of Public Health

Various chemometric methods were used to analyze and model potable water quality data. Twenty water quality parameters were measured at 164 different sites in three representative areas (low land, semi-mountainous, and coastal) of the Thessaly region (Greece), for a 3-month period (September to November 2006). Hierarchical cluster analysis (CA) grouped the 164 sample sites into two clusters (CA-group 1 and CA-group 2) based on the similarities of potable water quality characteristics. Discriminant analysis was assigned about 94.5% of the cases grouped by CA. Factor analysis (FA) was applied to standardized log-transformed data sets to examine the differences between the above clusters and identify their latent factors. For each of the above two clusters (CA-group 1 and CA-group 2), FA yielded six latent factors that explain 68.7% and 73.4% of the total variance, respectively. FA was also identified the latent factors that characterize each cluster. The identification was obtained, using (a) descriptive statistics, (b) t test for equality of cluster means, (c) box plot, (d) error bar, (e) factors score plots, (f) matrix scatter score means plot and (g) scatter plot of the six significant latent factors from the factor set of all samples group. The classification scheme obtained through cluster analysis was confirmed by discriminant analysis and explained by factor analysis