6.6 - Land Quality
Inherent Land Quality Assessment Descriptions
The ability of the land to perform its function of sustainable agriculture production and enable it to respond to sustainable land management. Class 1 is the class with the most desirable quality and class 9 is the class with the poorest quality.
The ability of the land to revert to a near original production level after it is degraded, as by mismanagement. Land with low soil resilience is permanently damaged by degradation.
The ability of the land to produce (as measured by yield of grain, or biomass) under moderate levels of inputs in the form of conservation technology, fertilizers, pest and disease control. Land with low soil performance is generally not suitable for agriculture.
Land Area Quality Distribution
|Land Quality Class||Land Area (million km2)||Cumulative Land Area (million km2)||Percentage of Land Area (cumulative)|
Table 2. Land area of each Land Quality Class. (Global land area: 130.575,894 km2)
Land Quality Class 1
This is prime land. Soils are highly productive, with few management-related constraints. Soil temperature and moisture conditions are ideal for annual crops. Risk for sustainable crop production is generally less than 20%.
Land Quality Classes 2 and 3
These soils have few problems for sustainable production. Their productivity is generally very high; however, care must be taken to reduce potential degradation. Risk for sustainable crop production is generally 20-40%, but risks can be reduced with good conservation practices.
Land Quality Classes 4, 5 and 6
These soils are not suited for grain crop production without important inputs of conservation management. In fact, no grain production must be contemplated in the absence of a good conservation plan. Lack of plant nutrients is a major constraint. Soil degradation must be continuously monitored. Productivity is not high. Risk for sustainable grain crop production is 40-60%.
Land Quality Class 7
These soils are definitely not suitable for low-input crop production. Their low resilience makes them easily prone to degradation. They should be retained as natural forests or range. Risk for sustainable grain crop production is 60-80%.
Land Quality Classes 8 and 9
These soils belong to very fragile ecosystems or are very uneconomical to use for crop production. They should be retained in their natural state. Risk for sustainable crop production is greater than 80%.