Nutrient cycling, water regulation, and other soil functions are normal processes occurring in all ecosystems. From these functions come many benefits to humans, such as food production, water quality, and flood control, which have value economically or in improved quality of life. People can increase or decrease the value of soil benefits because land-management choices affect soil functions. Thus, it is important to understand what benefits we derive from soil and their value so we can appreciate the importance of managing land in a way that maintains soil functions.
People tend to emphasize benefits with the most direct, private economic value. In rural areas, this is usually plant growth especially as crops and rangeland, but also as recreation areas. In urban/suburban areas, the most direct economic benefits of soil relate to structural support for buildings, roads, and parking. Landscaping, gardening and parklands may also be valued economically.
Those are all on-site, short-term benefits. That is, the landowner who decides how to manage the soil also reaps the benefits (and costs) of those management decisions. In contrast, many important benefits are long-term or go beyond the land being managed. The landholders who make the management choices and pay the costs of managing land may not be the same people who are affected by the landholders decisions. Society should discuss the value of these off-site benefits and to what extent the land owner or society should pay to maintain these soil functions.
Water quality of streams, lakes, oceans, and groundwater
Air quality, especially particulates
Greenhouse gases, including carbon dioxide, methane, and nitrous oxide.
Biodiversity
Water flow and flood control
Sustainability of land productivity
Aesthetics
Soil Function | Benefit of Value to Humans | |
---|---|---|
On-site | Off-site | |
Nutrient cycling | Delivery of nutrients to plants Carbon storage improves a variety of soil functions |
Enhances water and air quality Storage of N and C can reduce greenhouse gas emissions |
Maintaining biodiversity and habitat | Supports the growth of crops, rangeland plants, and trees May increase resistance and resilience to stress Reduces pesticide resistance |
Helps maintain genetic diversity Supports wild species and reduces extinction rates Improves aesthetics of landscape |
Water relations | Provides erosion control Allows on-site water recharge of streams and ponds Makes water available for plants and animals |
Provides flood and sedimentation control Groundwater recharge |
Filtering and buffering | Can maintain salt, metal and micronutrient levels within range tolerable to plants and animals | Improves water and air quality |
Physical stability and support | Acts as a medium for plant growth Supports buildings and roads |
Stores archeological items
Stores garbage |
Multiple functions | Sustains productivity | Maintains or improves air and/or water quality |