For a change I am going to start with the bad news. I am not a gloomy person. But if what I am about to say doesn’t scare the crap out of you I won’t have done my job.
Global warming isn’t the only environmental catastrophe we are facing. The Earth is running out of soil. The proper way is apparently to say that we are losing arable land and that the arable land available per person is falling. But I like to say we are killing the soil. The very soil our lives depend on.
I am going to begin with a decent general overview of the problem.
The world has lost a third of its arable land due to erosion or pollution in the past 40 years, with potentially disastrous consequences as global demand for food soars, scientists have warned.
The continual ploughing of fields, combined with heavy use of fertilizers, has degraded soils across the world, the research found, with erosion occurring at a pace of up to 100 times greater than the rate of soil formation. It takes around 500 years for just 2.5cm of topsoil to be created amid unimpeded ecological changes.
www.theguardian.com/…
But this article is from 2015. Has the trend continued? Yes, according to the UN.
#FridayFact: Every minute, we lose 23 hectares of arable land worldwide to drought and desertification
www.unenvironment.org/…
So what is this doing to our ability to feed the world?
To understand the impact you have to about the concept of Environmental Space.
“Environmental space” is the total amount of resources we can use (in a given time period) without compromising the ability of future generations to access the same amount. The global environmental space per capita can be calculated by dividing the total amount of natural resources and services to the total world population. By comparing this figure with the actual usage of the natural resources and services in a region or a country, the progress towards sustainable development of that region or country can be assessed. The comparison between regions, countries, and different geographical levels also indicates the evolution between them and toward sustainable development.
The production and consumption of products and services varies between industrialized and developing countries on an unequal basis. While the population of the industrialized countries is less than 20% of the world population, they consume 75% of the mineral resources, 70% of the paper and paperboard consumption, and 45% of the world meat consumption. Per capita, a person in industrialized countries consumes three times as much meat and nine times as much paper as a person in developing countries. The unequal share in environmental space is also exhibited in the production of pollution. On an annual basis, an average person in industrialized countries emits 10 times more CO2 than an average person in developing countries. By achieving an equal share of environmental space between people and between generations, sustainable development could be achieved.
www.sciencedirect.com/…
For those of you without access to sciencedirect here is the punchline of a major study on the food portion of environmental space.
L. Hens, L.X. Quynh, in Reference Module in Earth Systems and Environmental Sciences, 2016
Land and soil
There are around 1.5 billion hectares of arable land (land under temporary agricultural crops) on Earth. Most of the agricultural land is currently being cultivated. On average, each person on Earth had a share of 0.41 ha of cropland in 1961 but only 0.25 ha in 2015, despite the increase in arable land surface. The figure is expected decreasing further to 0.20 ha per person by 2050. The surface of irrigated land accounted for 20% of the total arable land and increases.
The environmental space for arable land decreases not only in quantity but also in quality. Around 30 million hectares of irrigated land are severely degraded by salinization and around 80 million hectares more are affected by water logging.
The arable land is unevenly distributed. In 2015 an average person in an industrialized country occupies 0.48 ha, while in the developing countries the comparable figure is 0.19 ha per person. The uneven distribution of environmental space when it comes to land resources is also reflected by other types of land use. In urban areas, housing and living space became scarcer as the urban population increased fast during recent decades. It is estimated that in Asia, 40% of the urban population lives in slums; meanwhile, in industrialized countries, around 7% of people do not have access to shelters of an acceptable quality.
And then there is the relationship between pollinator loss and farming practice. Without pollinators gardening and fruit growing become almost impossible. Yet creating more arable land puts pollinators at risk.
D.L. Wagner, in Encyclopedia of the Anthropocene, 2018
Agriculture
The need for arable land to feed human populations and the needs of wildlife have been in tension for millennia. One can look to Easter Island to see what the end game of man's resource overexploitation can lead to. Currently more than 1.4 billion hectares of land have been committed to agriculture. As human populations swell, especially in lower latitudes, even more forests will be cut, surface water and aquifers tapped, fertilizers applied, and pesticides broadcasted—all of which threaten insects and other biodiversity either directly (e.g., land conversion and pesticide exposure) or indirectly (e.g., water use and nitrogen and phosphorus pollution). Savannahs, prairies, and grasslands, with their deep fertile soils, lend themselves to immediate use for crop and pasturelands, and as consequence are collectively among the most threatened biomes on the planet. The clearing of tropical forests for farming and pastureland is happening at alarming rates and will have especially grave consequences for insect species diversity. It is a commonly held belief among biologists that while tropical rainforests comprise only 7% of the terrestrial land area of the planet they are home to 50% of the world's plant and animal species.
In temperate regions, there have been major changes in agricultural practices that are universally viewed as detrimental to wildlife. Today's industrialized mega-farms consist of much larger monocultures, often with genetically modified varieties that kill herbivores upon digestion; others have herbicide-resistant genes that facilitate the aerial broadcasting of herbicides that kill weeds and any other plants growing about the periphery of a tract that might have otherwise promoted biodiversity. Systemic insecticides are under scrutiny as these can get into nectar and pollen and lure bees and other pollinators to their demise directly or via nonlethal impacts that otherwise compromise the animal, for example, by weakening an individual's immune response.
The hedgerows that formerly supported numerous insects and vertebrates are now significantly reduced in acreage, have less floral diversity, are more impacted by insecticides, and consequently have reduced biotas—and the inhabitants, both bug and plant, tend to be rather weedy in nature. Lightly grazed pasturelands which were historically habitat for myriad early successional, sun-loving taxa such as bees, butterflies, and grasshoppers are no longer suitable because of herbicide use or because they are no longer profitable relative to larger resource-intensive cattle operations.
Much could be done to make modern farming practices more pollinator and otherwise ecofriendly and encouragingly there appears to be a groundswell of interest by many agro-businesses, conservation biologists, governments, and other stakeholders to do so.
Across much of Europe, pasturelands and seminatural grasslands, with low to moderate stocking, are home to myriad early successional plants and animals, including many rare butterflies that would disappear without grazing or functionally equivalent mowing and other fuel- and labor-intensive practices. In some instances, management and recovery plans for rare butterflies go so far as to recommend stocking densities for cattle and ponies.
And next we have to consider if as well as endangering pollinators modern farming practice may be making the loss of arable land worse.
The place to start is with Nitrous Oxide. Nitrous Oxide is an incredibly potent greenhouse gas.
One tonne of nitrous oxide is equivalent to 298 tonnes of carbon dioxide.
That is not a misprint.
theconversation.com/…
My neighbours are dumping nitrogen fertilizer on the land at an incredible rate. This is, as the link above says, incredibly wasteful farming practice. But it also releases Nitrous Oxide into the environment.
J.M. Cloy, K.A. Smith, in Reference Module in Earth Systems and Environmental Sciences, 2015
Nitrous oxide emissions from agricultural soils
Land-use change from forest to pasture or arable land has been concentrated in recent decades in the tropics. Research indicates that N2O emissions from such newly created pastures may be several times greater than those from paired forest sites, for the first few years after deforestation, but emissions from pastures more than 20 years old are less than those from forest soil. These emissions from new agricultural land in the tropics constitute only a small fraction of the total emissions from all agricultural land across the globe. The estimated size of the latter has risen gradually, as more and more research has been carried out, and is now put at more than 4 Tg N2O-N year− 1, albeit with a bigger uncertainty range than those for the natural ecosystems.
Included within this agricultural total are emissions from land receiving mineral N fertilizers and from land receiving animal manures, either applied by farmers or directly deposited as the excreta of grazing livestock. The steady increase in consumption of nitrogenous fertilizers and in the size of livestock populations has contributed to a corresponding increase in the size of the agricultural N2O source to its present-day level. Increases in food production are regarded as essential to meet the needs of a growing population, over the next few decades, and are likely to require increased use of N. This in turn may be expected to increase overall N2O emissions.
Increases in soil mineral N content as a result of N application to agricultural soils are characteristically followed by emission peaks, provided the soil is sufficiently wet.
And now comes the kicker. From the same research article.
Many research studies have reported nonlinear (exponential) increases in N2O emission rate with temperature, with values for the Q10 for the process (i.e., the ratio of the rate at T + 10° to the rate at T °) ranging up to 10 or more, compared with the general range of 2–3 for most biochemical processes.
In other words as temperature goes up soil produces more Nitrous oxide. Nitrous oxide potently causes a greenhouse effect. World temperatures rise and more Nitrous oxide is produced. And on and on.
I would think by this point you are beginning to get the general idea.
The population of the Earth is going up. And this neat real time estimate will bring it home to you.
www.worldometers.info/…
In the time it took me to write this diary the population of the Earth has increased by more than 16,000 people. In fact as of this writing so far today it has increased by more than 127,000 people.
Use of Nitrogen fertilizers definitely increases yields. And we need those increased yields to feed ourselves. Corn yields in the US for example, would drop by 40% without nitrogen fertilization. In wheat it is as much as 50% yield reduction.
The problem is that Nitrogen Usage Efficiency is typically only 50%. That is half the nitrogen added just goes back into the air as Nitrous Oxide or pollutes water ways.
iopscience.iop.org/…
The thing is, and I have seen this on my own land using nitrogen fertilizers and for that matter pesticides and herbicides is a losing game.
Agricultural practices that use high amounts of external-inputs, such as inorganic fertilizers, pesticides, and other amendments, can overcome specific soil constraints to crop production. These practices have led to considerable increases in overall food production in Europe, Asia and the Americas. However, especially in the most intensively managed systems, this has resulted in continuous environmental degradation, particularly of soil, vegetation and water resources, such as in the state of Haryana in India. Soil organic matter levels are declining and the use of chemical inputs is intensifying (Singh, 2000).
Any misuse of high external inputs for crop production has far reaching effects, which include:
- Deterioration of soil quality and reduction in agricultural productivity due to nutrient depletion, organic matter losses, erosion and compaction
- Pollution of soil and water through the over use of fertilizers and the improper use and disposal of animal wastes
- Increased incidence of human and ecosystem health problems due to the indiscriminate use of pesticides and chemical fertilizers
- Loss of biodiversity due to the use of reduced number of species being cultivated for commercial purposes
- Loss of adaptability traits when species that grow under specific local environmental conditions become extinct
- Loss of beneficial crop-associated biodiversity that provides ecosystem services such as pollination, nutrient cycling and regulation of pest and disease outbreaks
- Soil salinisation, depletion of freshwater resources and reduction of water quality due to unsustainable irrigation practices throughout the world
- Disturbance of soil physicochemical and biological processes as a result of intensive tillage and slash and burning.
www.fao.org/...
My largest field reached a point where there was no crop I could plant produced more income than the cost of production and harvest. 264 acres of worthless farm land. Then I talked to some other people in the area and we all were experiencing these decreasing yields and we were increasing fertilizer usage every year. They started buying organic matter and soil ammenders and are still eeking out a living.
I went in an entirely different direction. I stopped using chemicals all together. What happened next is a story for another day.
The Burdei is part of my new approach. I am building one on my ranch. It will be where I stay when I am working on the ranch. This one is at the Ukrainian Cultural Heritage Village. This is just east of Edmonton. I am modelling mine on this one. We will see how well I do. This one is incredibly cozy and warm. I hope I do as well.
I am trying to live in harmony with the land and that starts with living in harmony with the soil.
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