On Soil Capability, Capacity, and Condition

Abstract

The role of soil in the existential environmental problems of declining biodiversity, climate change, water and energy security, impacting on food security has highlighted the need to link the soil functions to ecosystem services. We describe and illustrate by a limited example, the concepts and assessment of soil’s capacity measured through its capability and condition as contributors to an overall soil security framework. The framework is based on the concepts of genosoils and phenosoils. The links to other notions, such as threats to soil and soil functions are made. The framework can be potentially applied elsewhere to quantify soil changes under natural processes and human activities.

Application of the Soil Security Concept to Two Contrasting Soil Landscape Systems—Implications for Soil Capability and Sustainable Land Management

“…The difference between the baseline condition of the soil in the reference state and the current soil condition, the phenoform [1] can be used as a quantified measure of the soil capability [1,2,16]. There is a recognition that soil capability has a link to soil management, and that soil should be managed within its capability [1,16,24]. McBratney et al [1] also recognise that the response of the soil condition to land management is included within the soil capability dimension, " .…”

“…It predicts the changes in soil condition between the genoform and phenoform. An important implication is that while soil condition indicates the actual state of the soil at the time of measurement, soil capability, while making assessment of the potential capacity of the soil to perform various functions [14,16], it also makes predictions about how soil condition changes with time. Hence, its assessment ideally should include information about land management and how this can change soil properties and about environmental variables such as climate and landform.…”

“…Soil condition refers to the current state of the soil and allows an assessment as to whether the soil is being managed according to its capability and how different the soil may be from a reference state. It allows an assessment of how management may have influenced any changes in the state of the soil [1,2,16,24]. Soil condition is linked to the concepts of soil quality and soil health and may be assessed using similar indicators or soil properties [1,22].…”

“…However, there still remains the need for clarification about the meaning and definitions of the dimensions used in the concept, particularly the dimensions of soil capability and soil condition. How land degradation processes, threats or "forcings" [16] associated with different land management practices are assessed is not specified. As it is currently proposed, the assessment of the impacts of land management on soil condition and land degradation processes or threats within the concept remains uncertain.…”

“…In fact, the statement is made within one publication on soil security, "Generally, the forcings are considered under various land degradation processes, such as, water or wind erosion, salinization, contamination, etc. However, strictly theoretically, we do not need to specify these forces of degradation" [16] (p. 5). Yet, unsustainable land management practices are the main drivers of land degradation.…”