Table 23.2
Linking Soil Health Measurements to General Management Solutions
Suggested Management Practices
Physical Concerns
Short-Term or Intermittent
Long-Term
Low aggregate stability
Fresh organic materials (shal ow-rooted cover/rotation
crops, manure, green clippings)
Reduced tillage, surface mulch, rotation with sod crops
Low available water capacity
Stable organic materials (compost, crop residues high
in lignin, biochar)
Reduced tillage, rotation with sod crops
Limited mechanical soil loosening (e.g., strip tillage,
High surface density
aerators), shal ow-rooted cover crops, biodrilling, fresh Shal ow-rooted cover/rotation crops, avoiding traffic organic matter
on wet soils, controlled traffic
High subsurface density
Targeted deep tillage (zone building, etc.); deep-rooted Avoiding plows/disks that create pans; reduced cover crops
equipment loads and traffic on wet soils
Biological Concerns
Low organic matter content
Stable organic matter (compost, crop residues high in
lignin, biochar); cover and rotation crops
Reduced tillage, rotation with sod crops
Low active carbon
Fresh organic matter (shal ow-rooted cover/rotation
crops, manure, green clippings)
Reduced tillage, rotation
Low mineralizable N
N-rich organic matter (leguminous cover crops,
Cover crops, manure, rotations with forage legume sod
manure, green clippings)
crop, reduced tillage
High root rot rating
Disease-suppressive cover crops, disease-breaking
Disease-suppressive cover crops, disease-breaking
rotations
rotations, IPM practices
Chemical Concerns
Low CEC
Stable organic matter (compost, lignaceous/cellulosic
crop residues, biochar), cover and rotation crops
Reduced tillage, rotation
Unfavorable pH
Liming materials or acidifier (such as sulfur)
Repeated applications based on soil tests
Repeated application of P, K materials based on soil
Low P, K
Fertilizer, manure, compost, P-mining cover crops,
mycorrhizae promotion
tests; increased application of sources of organic
matter; reduced tillage
High salinity
Subsurface drainage and leaching
Reduced irrigation rates, low-salinity water source,
water table management
High sodium
Gypsum, subsurface drainage, and leaching
Reduced irrigation rates, water table management
with chemical amendments. Fourth, there are important
a lot of available N for crops. The organic materials that
considerations relating to the type of organic materials
are dominated by stable materials that are high in lignin,
that are used. In chapters 9, 10, and 12 we discussed
like the residues of mature crops, and those that contain
different organic residues and manures and their effects
humic material, like composts, are critical to the long-
on soil health. One important distinction is whether the
term building of soil health. Biochar, which decomposes
material is mostly “fresh” and easily decomposable or
slowly over hundreds of years, is perhaps the most sta-
contains more stable compounds. Fresh materials like
ble material. If, for example, aggregate stability or active
manure, cover crops, and green clippings are high in
carbon levels are low, the application of easily decom-
sugars, cellulose, and proteins and have relatively high
posable materials will be beneficial in the short term.
N content (low C:N ratios). They immediately stimulate
However, these materials disappear quickly and need
soil biological activity, especially bacteria, and provide
to be added regularly to maintain good aggregation. For
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Building SoilS for Better CropS: SuStainaBle Soil ManageMent