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are low biomass generation, loss of SOC, and erosion of the rich fertile surface.
Therefore, management practices that augment soil organic matter and maintain it
at a threshold level are needed for better soil health (Srinivasarao et al. 2011 ).
Optimum levels of SOC can be managed by adopting the appropriate crop rotation,
fertility management, balanced use of chemical fertilizers and organic amendments,
and conservation practices. Continuous application of organic matter as farm com-
post, farmyard manure, and plant residues is needed to maintain/increase soil
organic matter content.
Use of bioinoculants can accelerate the soil building process and promote benefi-
cial soil microbe communities. Microbial inoculants are useful for improving all
soil types in diverse cropping systems of different agro-climatic zones. The diver-
sity and population of microbial communities have a major influence on soil char-
acteristics. The lifecycle (multiplication and death) of microorganisms add organic
matter to the soil. Microorganisms help in the release of many nutrients, previously
bound to soil particles, in the soil solution for plant uptake by digesting and decom-
posing complex substances. The buildup of soil humus from microbial activity
helps in soil aggregation. Improved organic matter (humus) content and soil aggre-
gation help to improve the nutrient status and water holding capacity of soil. The
long-term application of microorganisms can significantly improve the organic mat-
ter content of soil resulting in overall soil health improvement.
Soil management practices influence soil physical and chemical characteristics
and bring about changes in the soil microbial community structure and function.
Tillage is one such practice that has significant effects on soil biological properties.
A lower soil fungal:bacterial biomass ratio has been observed in soils under inten-
sive cultivation. No-tillage (NT) systems with reduced disturbance facilitate the
establishment and maintenance of extensive fungal hyphal networks while inten-
sive soil tillage mechanically disrupts soil aggregates and hyphal structure. Further,
the extension of fungal hyphae in undisturbed soils can translocate N and other
nutrients from the deeper soil inorganic pool to the C-rich surface residues thus
bridging the soil–residue interface to improve the nutritional status and promote
biomass (Srinivasarao et al. 2009 ). Govaerts et al. ( 2008 ) studied microbial popula-
tions in zero (ZT) and conventional tillage (CT) with and without residue retention
in wheat and maize (Zea mays L). ZT and CT with residue retention had increased
populations of total bacteria, fluorescent Pseudomonas and Actinomycetes. ZT
without residue retention had very low populations of microflora while CT with
residue removal had a predominance of total fungi. This study divided management
practices into three groups: (1) ZT and CT with residue retention showing improved
soil health, (2) CT without residue showing intermediate soil health, and (3) ZT
without residue showing the worst soil health. These results indicated that zero till-
age with residue removal is an unsustainable practice, therefore, ZT should be com-
bined with an adequate level of residue retention. Chen et al. ( 2009 ) investigated
changes in soil properties in a long-term tillage experiment in a winter wheat mono-
culture in a semi-arid, semi-humid, continental climate with mean annual precipita-
tion of 555 mm. The effects on soil properties of CT with residue removal, shallow
tillage with residue cover (ST) and NT with residue cover were investigated. The
M. Grover et al.