Evaluation of Compost and Biochar as Partial Substitutes of Peat in Growing Media and Their Influence in Microbial Counts, Enzyme Activity and Lactuca sativa L. Seedling Growth

Abstract

The main organic input for the elaboration of growing media is peat (Sphagnum spp.), due to its physical and chemical characteristics. However, the mining of this material creates a considerable impact in the local ecosystems from which this is obtained, along with a global impact because of the emission of greenhouse gasses. Thus, sustainable materials that can replace, or reduce the use of peat, while maintaining or improving attributes in the growing media and plant growth, are greatly needed. Therefore, this work aims to evaluate the effects of the use of different proportions of compost and biochar on the biological characteristics of growing media and (Lactuca sativa L.) seedling growth prior to transplanting. Out of the biological variables evaluated, the β-glucosidase activity showed the greatest results in growing media based on 80% peat and based on 70% peat, 5% compost and 5% biochar. Moreover, growing media based on the combination of compost, biochar and peat maintained most of the Lactuca sativa L. (Oak Leaf variety) seedling traits obtained in the growing media based on only peat. These findings emphasize the need to further investigate further biological conditions for alternative materials to peat, and the need to pay attention to feedstock initial characteristics and processing in order to obtain high quality organic inputs for optimum growing media.

Effect of Compost from Cardoon Biomass, as Partial Replacement of Peat, on the Production and Quality of Baby Leaf Lettuce

“…Moreover, as for our results, some compost-based substrates of cultivation improved plant growth more than the peat-based ones, achieving higher yields [73]. It has been shown that suitable characteristics of water-holding capacity, EC, aeration, and bulk density allow satisfactory conditions for healthy plant growth, which guarantees an increase in the photosynthetic potential of the leaves [11,67,69]. These characteristics are affected by the porosity in the media, which promotes plant growth [69].…”

“…However, all were between 10 and 20 percent of dry matter, a range considered desirable for a quality compost. The pH and conductivity values were comparable among the composts and in a range suitable for use as a growing medium component [11,13]. The germination indices (GI) found, being higher than 65%, indicated the absence of phytotoxicity in the three composts [52].…”

“…Various materials, such as municipal solid waste, sawdust, biomass waste, digestate, and biochar after proper transformative processes (such as composting, pyrolysis, etc. ), were favorably valued when mixed with peat in horticultural media [10][11][12][13][14][15]. Among them, compost is successfully used as a replacement for peat to produce seedlings of tomato (Solanum lycopersicum L.) in nurseries [16] and plants of tomato and basil (Ocimum basilicum L.) in pots [17].…”

The potential use of brewers' spent grain-based substrates as horticultural bio-fertilizers

“…Positive effects resulting from the use of organic substrates, both as actual growth substrates in the seeding phase (Dhen et al, 2018;Gomah et al, 2020;Qin and Leskovar, 2020;Sarkar et al, 2021;Guan et al, 2023;Rozas et al, 2023) and as biofertilizers during the crop cycle (Suwor et al, 2020;Yoo et al, 2021;Melito et al, 2023;de Lima et al, 2024), were observed. Therefore, the utilization of these BSG-based substrates could be promoted as horticultural bio-fertilizer and valid alternatives to chemical fertilizers, both during the seedbed phase and throughout the crop cycle.…”

Optimization and Experiment of Livestock and Poultry Manure Composting Equipment with Vented Heating

“…Simultaneously, Inner Mongolia is also a major distribution area for corn cultivation in China. After the corn harvest, a large amount of straw is produced, which contains rich organic matter that can enhance the compost's organic matter content and increase the final product's value [40][41][42][43]. Thus, sheep manure and corn straw were chosen as composting materials for the experiments.…”