Fertility of the soil is the future of civilization. ~ English botanist and agriculturalist Albert Howard
The world grows 95% of its food in topsoil, making soil the foundation of humanity’s food system. Dirt is commonly taken for granted, but the quality of soil has always been a major determinant of what will grow and to what yield.
pH regulates the capacity of soils to store and supply nutrients. Soil which is too acidic renders phosphorus insoluble, and thereby inaccessible. Phosphorus is essential for plant growth.
Soil pH is controlled by environmental factors, especially the level of rainfall. There is an abrupt transition from alkaline to acidic soil when precipitation exceeds evapotranspiration: the loss of water from the soil by both evaporation and plant transpiration. Evapotranspiration causes most of the water lost from the soil during the growth of a crop.
Climate creates a nonlinear pattern in soil solution chemistry at the global scale. ~ American soil ecologist Eric Slessarev
It was long assumed that soil comprises inherently stable chemical compounds. Instead, organic matter which is critical to soil quality progressively decomposes. Thus, soil fertility is an active process, involving the microbes within, the plants that cover the ground, and the atmospheric environment, including temperature, rainfall, and air quality.
As earth is both a sink and source of moisture in the air, soil quality has a direct link to the global water cycle.
Soil may be altered rapidly in response to climate change. Changes in soil hydraulic properties set up feedbacks between climate and the land surface and thus intensify the water cycle. ~ American Earth scientist Daniel Hirmas et al
Soil is itself a complex and fragile ecosystem. The soil creation process is so slow that soil is a nonrenewable resource.
Soil, once eroded or depleted, takes centuries – millennia even – to recover. ~ American geologist Frank Rhodes
Plants create ecosystems that nurture and protect the soil upon which they depend. If these critical caretakers are disturbed, soil degrades, sometimes irredeemably so. Man’s neglect of soil has often led to its critical vitality being lost. For farmers trying to lift themselves out of poverty, poor soil can leave them sunk in a mire of desperation.
Poor soil constrains agricultural production and household capital, and low household capital constrains investments in improving soils. ~ American economists Christopher Barrett & Leah Bevis
From 1975–2015, the world lost 1/3rd of its arable land due to pollution and erosion. This far outstrips the pace at which natural processes can replace degraded soil. American cropland topsoil is eroding 10 times faster than Nature can replenish it.
The modern combination of intensive tilling, lack of cover crops, synthetic fertilizers and pesticide use has left farmland stripped of the nutrients, minerals, and microbes that support healthy plant life. ~ American environmental scientist Susan Cosier
Soil erosion has largely occurred through the continual disturbance of planting and harvesting crops. Repeatedly turning over soil exposes it to oxygen, thereby soil releasing its carbon into the atmosphere. Disturbed soil fails to bind effectively, losing integrity. This impacts soil’s ability to store water, neutralizing its role as a buffer to floods. Hence, soil loses its ability to serve as a fruitful base for plants.
We are increasing the rate of loss and we are reducing soils to their bare mineral components. We are creating soils that aren’t fit for anything except for holding a plant up. ~ English ecologist Duncan Cameron
Half of global agricultural land is degraded. Of this, the majority is so damaged that local farmers have been unable to restore it.
Our planet’s soils are under threat. In some places soil is being lost 100 times faster than it forms. ~ English environmental engineer Steve Banwart
Deforestation, which takes away the trees that knit landscapes together, is also detrimental to soil health. Degraded soils are vulnerable to being washed away by weather events from global warming.
Pathetic soils are silting river systems. The gigantic brown stain where the Amazon River deposits soil into the Atlantic Ocean is illustrative.
30% of arable land is used to keep livestock rather than grow crops. This exclusivity runs counter to good soil management.
We need a radical solution, which is to re-engineer our agricultural system. We need to take land out of production for a long time to allow soil carbon to rebuild and become stable. We already have lots of land – it’s being used for pasture by the meat and dairy industries. Rather than keep it separated, we need to bring it into rotation, so that that there is more land in the system and less is being used at any one time. ~ Duncan Cameron
The impediment to implementing a rational solution for maintaining soil quality is private property, which precludes proper employment of land resources. The larger picture is the capitalist system, which atomizes decisions and hampers coordinated action which might otherwise optimize resource allocations.
Soils comprise a dynamic reservoir of biodiversity within which the interactions between microbes, animals, and plants provide many benefits for human well-being. Living soils are vital to humans because soil biodiversity not only provides disease control, but also influences the quantity and quality of the food we eat, the air we breathe, and the water we drink. ~ American ecologist Diana Wall et al