Agriculture Reference
In-Depth Information
5.3.3.4
Enzyme Activities
Various hydrolytic enzymes (cellulase, xylanase and protease) are believed to con-
trol the rate at which different substrates are degraded. Enzymes are the main me-
diators of various degradative processes (Tiquia et al.
1996
). Maximum activities of
cellulase, xylanase and protease observed between 30 and 60 days of composting
can be taken as index of compost maturity (Goyal et al.
2005
).
5.4
Compost Quality Standards
Different official and private organisations (European commission
2001
; TMECC
2002
; BOE
2005
; BSI
2005
; Ge et al.
2006
) proposed many compost quality stan-
dards by taking into consideration compost properties viz. foreign matter (inert con-
tamination), potentially toxic elements (organic contamination and heavy metals),
sanitisation (pathogens and phytopathogens), maturity and stability, weed seeds,
water, OM and nutrient content (Bernal et al.
2009
). At present, there is a need for
standardization of such criteria at the international level.
5.5
Conclusion
The composting of organic waste materials has been demonstrated to be an effec-
tive method of producing end-products which are stabilized, ensuring their maxi-
mum benefit for agriculture. Composts are valuable products which can be used
as sources of soil amendment and organic matter in agricultural land. Composts
prepared from different organic wastes differ in their quality and stability. Several
indices based on physical, chemical and biological parameters have been used for
compost by different authors. Despite all the proposed methods to establish the
degree of maturity and stability of composts, no single method can be universally
applied to all composts due to wide variations in composition of raw material used
for composting and composting technology. Hence, compost maturity should be as-
sessed by measuring two or more parameters. However, it is necessary to standard
the criteria used by official institutes from different countries.
References
Adani F, Genevini PL, Tambone F (1995) An new index of organic matter stability. Compost Sci
Util 3(2):25-37
Albonetti SG, Massar G (1979) Microbiological aspects of a municipal waste composting system.
Eur J Appl Microbiol Biotechnol 7:91-98
Antil RS, Raj D (2012) Chemical and microbiological parameters for the characterization of
maturity of composts prepared from farm and agro-industrial wastes. Arch Agron Soil Sci
58:833-845
