Soil loss by erosion and contamination are the main causes of soils degradation in Europe, and tipically soils degraded are characterized by low microbial functionality. One of the effective way to restore the functionality in degraded soils is the use of organic amendments. The use of hydrolysates from organic by-products as plant biostimulant increased in the recent years, but their effect of soil microbial biomass is not well understood. With this aim we used four biostimulants obtained through enzymatic and thermal hydrolysis of organic by-products: yeast extracts (YE) and animal collagen (AC). A degraded soil was treated with different doses of biostimulants, and the soil respiration rate (SRR), the soil microbial activity (SMA), and the soil microbial biomass (SMB) were monitored over a 30 days period. SRR increased quickly in the soil treated with YE (maximum 2-3 days after adding), than AC (maximum 5-9 days after adding). After 3 weeks, the SRR reached the steady state, and it was higher in the soil treated with YE, than AC. The trend of SMA was similar to SSR, and after 4 weeks of incubation was not possible to observe significant differences between treatment. All treatments increased SMB compared to the untreated soil: biostimulants from AC are those that showed the highest increase. The results here obtained demonstrate that it is possible to increase the functionality of degraded soils using hydrolysates from agro-industrial by-products, although the results were influenced by the raw material and the production process used.
Biostimulants from Organic By-Products: a Good Way to Enhance Soil Functionality
CAVANI, LUCIANO;CIAVATTA, CLAUDIO
2015
Abstract
Soil loss by erosion and contamination are the main causes of soils degradation in Europe, and tipically soils degraded are characterized by low microbial functionality. One of the effective way to restore the functionality in degraded soils is the use of organic amendments. The use of hydrolysates from organic by-products as plant biostimulant increased in the recent years, but their effect of soil microbial biomass is not well understood. With this aim we used four biostimulants obtained through enzymatic and thermal hydrolysis of organic by-products: yeast extracts (YE) and animal collagen (AC). A degraded soil was treated with different doses of biostimulants, and the soil respiration rate (SRR), the soil microbial activity (SMA), and the soil microbial biomass (SMB) were monitored over a 30 days period. SRR increased quickly in the soil treated with YE (maximum 2-3 days after adding), than AC (maximum 5-9 days after adding). After 3 weeks, the SRR reached the steady state, and it was higher in the soil treated with YE, than AC. The trend of SMA was similar to SSR, and after 4 weeks of incubation was not possible to observe significant differences between treatment. All treatments increased SMB compared to the untreated soil: biostimulants from AC are those that showed the highest increase. The results here obtained demonstrate that it is possible to increase the functionality of degraded soils using hydrolysates from agro-industrial by-products, although the results were influenced by the raw material and the production process used.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
