Land & Soil Degradation: Types, Causes, Effects, & Solutions

Land and soil are some of the most important resources to humans on Earth.

So, it’s important to learn about how they can be degraded (and conserved/protected).

In this guide, we look at what land degradation is, the main types, the causes, the effects/impact, and the potential solutions to prevent it.

 

Summary – Land & Soil Degradation

We rely on soil and land … to live on, produce our food, make our clothes, support plant and animal life. There’s a number of important human uses for land and soil

Land degradation is the blanket term usually used to describe a number of land and soil degradation issues

Land and soil degradation can take many forms – up to 36 of degradation types exist

Some of the major types of land degradation include soil erosion, soil contamination (one form of land pollution), desertification, soil acidification, and soil salinity

Causes for land and soil degradation can differ from country to country (geographic region to region), in urban vs rural areas, and on agricultural vs non agricultural land

As one example, the primary cause for land and soil degradation in a country in a selected country in Africa might be different to the primary cause for land and soil degradation in a State in the US

Some of the major general causes include wind and water weathering of soil, deforestation and clearing of land, intensive or unsustainable agricultural practices, mining, urbanization and human development, carrying of contaminants by air and water, leaching and run off of contaminants, improper management/disposal of waste, natural or severe weather events

There’s also indirect factors that can contribute to land and soil degradation, such as human population growth, which can place more pressure on land and soil resources

For agricultural land in particular, the main causes of erosion might be intensive cultivation, overgrazing by livestock, poor management of arable soils, and the clearing of land to convert it to land for farming (although it differs between developed and developing countries – industrial agriculture vs pasture grazing for example)

According to some estimates … in non rural areas – wind and soil erosion might account for over 80% of land degradation, and in rural areas over 70% might be caused by overgrazing and agricultural activities.

Estimates indicate that a third to a half of the world’s agricultural land is moderately or seriously degraded.

Estimates also indicate that countries like American have lost about half their topsoil since colonial days.

Countries in Sub Saharan Africa might be worst affected by land and soil degradation globally.

We’ve further outlined what various sources say the extent of land/soil degradation in different parts of the world are in the guide below

One effect of land and soil degradation is lost productivity/yield on agricultural land, and some estimates indicate that productivity may have reduced by 20% to 30% in some regions

Economically, some estimates put the economically loss that land and soil degradation is responsible for at tens of billions of dollars worldwide annually

We’ve outlined some of the other potential effects/impact of land and soil degradation in the guide below, and this guide outlines other benefits of land and soil that land/soil degradation may detract from

Degradation of the world’s arable land and top soil might be a significant issue for the future – some estimates indicate we may only have 60 years worth of harvests in top soil left in some countries

Read more about agricultural topsoil degradation and erosion in this guide. Note that land degradation might be a slightly different set of issues to the specific issue of agricultural topsoil erosion, which solely focuses on the loss of the naturally formed upper fertile layer of the soil

Solutions to land and soil degradation should ideally be aimed to address the main causes contributing to land and soil degradation in a specific geographic region, or on a specific area of land (as each region and area of land has different causes for it’s soil and land degradation)

The best solution to land and soil degradation might be to prevent it from happening in the first place, but there can be solutions to restoring already degraded land/soil

As just one example of a possible solution aimed at a specific cause of land degradation, ground cover, cover crops, and building up the top layer of soil (with more organic matter), may all help protect against soil erosion, and particularly wind and water erosion

Another example – crop rotation might improve soil health over the long term

Another example – better rotating livestock on different plots of pasture land might help prevent overgrazing

Another example – using natural fertilizers (like animal manure, or organic matter), and natural or biological pest control methods, over synthetic fertilizers and pesticides, may be one way of reducing soil contamination. Other ways might be limiting general water, air and waste pollution that can leach into soil and onto lands from the various parts of society. Better sealing landfills might be one specific way to prevent soil contamination at landfill sites.

Already polluted and contaminated soil might have it’s own set of solutions to consider, such as removing, treating, aerating, and remediation of soil

Funding large scale projects to restore significantly damaged and degraded soil and land is an option for already degraded land.

Although, what is apparent is that each region has different causes of land degradation, along with different local climates, conditions, pre existing soil profiles and makeup (some soils are difficult to work with, lack organic matter, or are unresponsive), farming practices, local knowledge – factors that lead to addressing land and soil degradation having unique challenges in each area. Dry land restoration in particularly can be uniquely challenging

There’s more potential solutions to land degradation and soil erosion below in this guide

Some effects of some types of land degradation, such as some types water and wind erosion, may be largely irreversible – at least over the span of thousands of years (top soil can take millennia to form again naturally). 

Other types of land degradation are reversible – but, can differ in the amount of time and money required to address them, and some types of land degradation are easier to address than others

There might need to be an assessment of what land degradation problems can practically be fixed (and what ones we can’t), along with the effectiveness of pursuing certain solutions, as well as the expected ROI and benefits

 

First, How Do We Use Land On Earth?

Before we look at how land is being degraded, it’s a good idea to get an overall idea of the different uses of land on Earth.

This guide also specifically outlines how agricultural land is used on Earth.

 

What Is Land Degradation?

Land degradation is a very broad term used to describe a range of different types of land and soil degradation.

Land or soil that is classified as degraded might have some or all of the following features:

– A change or damage to the land or soil

Caused by either physical actions, or a chemical (such as synthetic or hazardous chemical – like pesticides)

Land degradation can be direct (where land or soil is directly damaged), or it can be indirect (where for example contaminated water leaches from it’s source onto a land/soil source)

And, it can be caused by humans (such as farmers), or a natural factor (such as weather)

An example of a change or damage to land/soil is the erosion or removal of the fertile level of topsoil on the land.

 

– Results in reduced potential for, or complete loss of, the land being used for any number of land uses

Mining is one example where after land is mined, it might have limited uses afterwards.

Another example is land that has reached a certain level of desertification, that there’s limits to how effectively it can be restored, re-greened or re-used.

 

– The value of the land for humans, animals, plant/vegetation and organisms is lessened as a result of the land degradation

As an example, land used for food production might be worth less in a monetary sense over time if land/soil degradation leads to a decrease in yield/productivity (which limits the profit potential for those producing food or other agricultural products on the land)

 

What Is Considered Land Degradation Might Differ Between Different Parties

Something that is interesting to note is that what is land degradation to some, may not be to others.

For example, an environmentalist or scientist may look at the environmental aspects of how farmed land is being used, whereas a farmer might look at the economic aspect of what that land can provide once cultivated or used in another way for economic and human benefit.

 

Types Of Land Degradation

There can be many types of land degradation.

Overall, there are up to around 36 types of land degradation in total.

But, some of the major types to be aware of might be:

 

Soil Erosion

One of the most prominent types of land and soil degradation.

Is a partial or complete loss of the top fertile layer of soil i.e. the topsoil (arable land in particular has fertile soil used to grow crops.)

This soil layer usually contains minerals and nutrients (and usually beneficial microorganisms) to grow crops and plant life, and is characterised by decayed/decomposed organic matter (from plants and animals) which has usually spent many years being developed by the break down of organic matter

Several sources claim this is a problem because it takes many years to naturally develop topsoil again

In some cases, top soil can’t be regenerated.

Other sources do say that topsoil is renewable with organic fertilizer/manure and other solutions though.

Erosion includes natural wind erosion and water erosion, but also human induced mechanical erosion such as overgrazing with livestock, over tilling, and so on

In the instance of deforestation (or land clearing to convert land from one use to another), the top hummus and leaf litter layer that protects the fertile soil below it can sometimes be removed. 

 

Read more about issues related to topsoil loss/topsoil erosion in this guide:

How Much Topsoil Do We Need For Agriculture, How Much Is Left, & Will The World Run Out In The Future?

 

– Soil Contamination

When the chemical composition/properties of the soil/land are changed (as opposed to the physical).

Change can be direct such as contamination via agricultural chemicals (fertilizers and pesticides), dumping of industrial chemicals, the improper disposal of hazardous waste such as radioactive waste, or a number of other types of chemicals or waste.

Or, change can also be indirect such as polluted water and air changing the chemical composition of the soil. Acid rain and nitrogen emissions in the air are examples of this.

 

– Desertification

Includes land degradation in arid/dry zone areas

It happens when soil loses all it’s water and green matter.

In this case, it can be very hard to restore the land, and sometimes some damage is irreversible depending on the desired end land use.

 

– Soil Acidification

Is a reduction in the pH of soil

When the soil becomes too acidic, it can lose it’s productivity (for some types of production).

This can be a problem for agriculture, beneficial microorganisms, plant life and general soil health.

It can be caused by soil amendments like fertilizer, but also acid rain, nitrogen emissions in the air, and other factors.

 

– Soil Salinity

Is an increase in the salt content/saline concentration of the soil

When the soil becomes too saline, it loses it’s productivity (for some types of production)

It can be caused by ocean environments, over irrigation, water sources with salinity issues, and other factors.

Can particularly be a problem for coastal land, land with raised saline groundwater aquifer levels, and land with poorly managed or excess irrigation.

Australia in particular has issues with soil salinity in some states and geographic regions (and some countries around the world are more prone to soil salinity issues than others).

 

– Other

Apart from these land and soil degradation issues, land scarcity (especially the scarcity of agricultural and arable land), and land use (including the clearing of forests to convert forest land to another land use such as agricultural production), are a few other land/soil related issues.

 

Causes & Sources Of Land & Soil Degradation

There are different causes for the different types of land degradation.

Additionally, these causes differ from region to region within countries, and also between different countries.

For example, the primary causes of land degradation in a country in Africa might be different to a State in the US, and can be different again to a State in Australia.

The causes depend on factors like what agricultural practices and technology are used (how intensive they are for example), whether it’s a developed or underdeveloped region, and even external factors like overpopulation.

Beyond the specific causes of land degradation, the general causes of land degradation are usually either:

– physical causes, or chemical causes

– natural causes, or human causes

– direct causes, or indirect causes

Soil erosion for example happens via wind, and water from rain – which are natural causes.

But, it can also happen from deforestation, over-cultivation and over-grazing, and other human causes.

Another example is soil contamination.

This is primarily a human caused land degradation issue, with agricultural chemicals and industrial chemicals being significant chemical contaminants.

Waste disposal, mining, urbanization, agricultural chemicals, atmospheric deposition, soil erosion might be seen as the major causes of land degradation.

More specifically, the causes of land degradation overall might be …

 

– Wind and Water Weathering Of Soil

The basic factors causing soil erosion-induced degradation are wind and water erosion ( ommegaonline.org)

Wind and water weathering removes small amounts of the top soil from farming land

 

Deforestation, Logging & Clearing Of Land

Forest land can be cleared and converted to land to be used for agricultural production.

In this process, the ground cover is cleared, exposing the top soil, or removing the top soil completely.

Biodiversity is also degraded with the clearing of ecosystems and organic matter.

 

Deforestation accounts for the major land degradation problem as it results in severe soil erosion, flood, and loss of fertile soil (sciencedirect.com)

 

– Industrial Agriculture, Intensive Or Unsustainable Farming Practices, Or Mismanaging Land

This can include overgrazing, over tillage, over fertilizing (nitrogen can become excessive), over application of pesticide and herbicide, over irrigation or improper irrigation, and other factors.

Fertilizers, pesticides and other features of industrial and intensive farming can mask soil productivity and yield decreases in the short term – so the long term unsustainability of these things can be hidden

Additionally, farmers might not set up land conservation practices like ground cover and soil/water drains that can maintain land and top soil.

 

… the biggest [cause of land degradation] is the expansion of industrial farming.

Heavy tilling, multiple harvests and abundant use of agrochemicals have increased yields at the expense of long-term sustainability.

[some of the drivers of industrial agriculture and intensive farming practices are] high levels of food consumption, high levels of meat consumption, poor land regulation and poor farming efficiency can compound land degradation effects

– theGuardian.com

 

Read more about how agriculture can lead to land and soil degradation in this guide

 

Mining

Excavation, and mining waste and tailings, can cause contamination and degradation

Additionally, once mining is finished, the land on the ex-mining site can be unsuitable for some land uses.

 

– Urbanisation, & Human Development

Development of cities, towns, infrastructure, roads etc. involves the clearing of green land and soil.

 

– Atmospheric Deposition, & Leaching Of Chemicals

Leaching or carrying of chemicals (by wind, water etc.) from one location to another, where land/soil becomes contaminated or degraded.

For example, pesticides can be carried in the air from one place to another.

Oil can also leach from roads and major highways onto (into) land and water sources

 

– Improper Management/Disposal Of Waste

Includes hard waste, water waste, human sewage, and other types of waste.

Can cause soil contamination and land pollution.

Mismanaged landfills are another example of this – where leachate can leak out and contaminate soil.

There’s also hazardous chemicals and substances that can be mismanaged, such as radioactive waste.

 

– Natural Or Severe Weather Events

Floods, hurricanes and other natural events can all cause damage to land and soil.

 

– Indirect Factors

A changing climate, air pollution, water pollution, a growing population, and other potential indirect factors

Overpopulation as one example puts pressure on land and soil through increased demand for intensive agriculture, increased urbanisation, increased water and air pollution, more waste produced, and so on

 

Other information on causes of land and soil degradation …

 

The causes of soil destruction include chemical-heavy farming techniques, deforestation which increases erosion, and global warming [more severe weather events like droughts can deprive soil of moisture] (scientificamerican.com)

 

… land is moderately to highly degraded due to the erosion, salinization, compaction, acidification and chemical pollution of soils (fao.org)

 

Urbanisation, climate change, erosion and forest loss [are all causes of land degradation].

But the biggest [cause of land degradation] is the expansion of industrial farming [and a lot of this is driven by overconsumption or high rates of consumption of food]

– TheGuardian.com

 

Wikipedia.org outlines the causes of soil contamination as:

Soil contamination in particular might be caused by [any type of chemical, waste, or substance that gets into or on the soil – Wikipedia.org makes an extensive list of them]

The most common chemicals involved are petroleum hydrocarbons, solvents, pesticides, lead, and other heavy metals.

Any activity that leads to other forms of soil degradation (erosion, compaction, etc.) may indirectly worsen the contamination effects in that soil remediation becomes more tedious.

 

The bbc.com resource listed outlines some further causes of erosion and land degradation in the US, especially on cropland, and in specific States like Iowa. In Iowa for example, the resource outlines tilling over the years, along with disturbance from farm vehicles, as the two reasons that have allowed water and wind to erode Iowa’s topsoil.

 

You can see a good visualisation of soil contamination and how it might be caused here:

Soil & Water Contamination Infographic (visual.ly)

 

Read more about land degradation causes in different parts of the world at:

Major causes of land degradation, but also soil loss cause by region of the world (fewresources.org) – we see in Africa overgrazing is the major cause, but in North America it’s agricultural practices

Causes of land degradation in developing countries (ommegaonline.org)

The problem of land degradation, and causes in different parts of the world (fao.org)

 

What Does The Data Say The Main Causes Of Land Degradation & Soil Erosion Are?

It might differ depending on the region where the land and soil is.

In non rural areas – wind and soil erosion account for over 80% of land degradation

In rural areas – over 70% is caused by overgrazing and agricultural activities.

 

Some data and stats on the causes of land degradation are:

Non Rural Areas

Land degradation is caused by soil water erosion (46%) wind erosion (36%), loss of nutrients (9%), physical deterioration (4%), and salinization (3%) (sciencedirect.com)

 

Rural Areas

Overgrazing (49%) followed by agricultural activities (24%), deforestation (14%), and overexploitation of vegetative cover (13%) are the primary causes of land degradation in rural areas (sciencedirect.com)

 

What Causes Land/Soil Degradation Specifically To Agricultural Land?

The causes for agricultural land and soil degradation might be different to the causes on non agricultural land.

The causes can differ country to country (and especially from the most technologically advanced to the least), but might be:

 

The main causes of erosion on agricultural land are intensive cultivation, overgrazing, poor management of arable soils and deforestation

Acidification, compaction and salinization are some other causes of agricultural land degradation.

– ommegaonline.org

 

What Is The Extent Of Land & Soil Degradation, & Where Is It Happening? 

As noted above with causes, land degradation is happening to different extent:

– in different countries and states/provinces

– on non agricultural and agricultural land, and

– in urban and rural areas

Land degradation has been a more significant issue in developing countries than developed countries.

But, it’s becoming more of an issue now in developed countries too.

What should also be noted about land degradation is that it is harder for to see with the naked eye – you can see some signs of things like erosion and desertification, but you can’t see what is happening underground or what chemicals are in the ground, or the quality or thickness of fertile soil.

For these reasons, people may not think land degradation is as big of an issue as it really is.

Estimates indicate that a third to a half of the world’s agricultural land is moderately or seriously degraded.

Estimates also indicate that countries like American have lost about half their topsoil since colonial days.

Countries in Sub Saharan Africa might be worst affected by land and soil degradation.

From the various effects of land and soil degradation observed, lost productivity of the land/soil is one, and some estimates indicate that productivity may have reduced by 20% to 30%.

 

Some stats on the extent of land and soil degradation and where it is happening (worldwide and country specific) are …

 

Land Degradation

It is estimated that up to 40% of the world’s agricultural land is seriously degraded (wikipedia.org)

 

It is estimated that … 33 percent of land is moderately to highly degraded (fao.org)

 

One-third to half of the world’s agricultural land was in a degraded state in 2010, and a quarter was severely degraded …

… another 12 million ha are lost each year due to poor soil and water management and other unsustainable farming practices …

– ommegaonline.org

 

Global rates of soil erosion have been exceeding those of new soil formation by 10- and 20-fold on most continents of the world in the last few decades.

Desertification affects about one-sixth of the world’s population and one-quarter of the world’s land

Salinization affects some 20 million hectares of irrigated land.

– sciencedirect.com

 

A third of the planet’s land is severely degraded and fertile soil is being lost at the rate of 24bn tonnes a year

The impacts [of land degradation] vary enormously from region to region … [with the] Worst affected [being] sub-Saharan Africa, but poor land management in Europe [is also a problem]

… sub-Saharan Africa, south Asia, the Middle East and north Africa will face the greatest challenges [in the future] unless the world sees lower levels of meat consumption, better land regulation and improved farming efficiency.

– theguardian.com

 

Of the 80 countries substantially affected by land degradation, 36 are situated in Africa.

In Lesotho … approximately 2% of the total land area … has been degraded due to overgrazing and incorrect farming practices, as well as mismanagement of rangeland and residues from chemicals/pesticides

– apps.who.int (World Health Organisation)

 

In the Philippines … it is estimated that soil erosion carries away a volume of soil equivalent to one metre deep over 200 000 hectares every year.

In India, some 144 million hectares of land are affected by either wind or water erosion.

In Pakistan, 8.1 million hectares of land have been lost to wind erosion and 7.4 million hectares to water erosion.

– fao.org

 

… decreasing productivity can be observed on 20% of the world’s cropland, 16% of forest land, 19% of grassland, and 27% of rangeland (TheGuardian.com)

 

More resources that outline where land degradation takes place in the world, and stats on how much land degradation and erosion is happening can be found at:

Mapping the world’s degraded lands (sciencedirect.com)

Soil fertility and erosion information and stats (globalagriculture.org) 

 

Topsoil Degradation & Erosion/Loss

Read more about agricultural topsoil degradation and erosion in this guide.

Note that land degradation might be a slightly different set of issues to the specific issue of topsoil erosion.

 

Potential Effects & Impact Of Land Degradation

There’s a number of potential effects of land and soil degradation.

Some of the large level effects might be related to land and soil’s:

– Role in helping regulate aspects of the environment 

– Role as resources humans use to produce other resources, such as food and fibres, just as two examples. With a growing population, growing demand, and more resource intensive products being consumed, there will need to be more production or better efficiency in the future from land resources, not less (and degraded land and lost topsoil usually leads to less productive soil).

Read more in this guide about why land and soil are important to society to get more of an idea of the benefits that land and soil degradation can impact.

 

As a brief summary, land and soil degradation might impact:

– Soil fertility and soil health (read more about factors that can impact soil fertility in this guide)

– Land used for agricultural production, and obviously agricultural production itself. Specifically the yield/productivity of arable land used to grow crops. But, also pasture land that has been overgrazed

– Agriculture’s contribution to the economy, and the economic contribution of other industries that rely on land and soil

– Humans’ health and well being, in the instance where contaminated soil leaches into water supplies. Poor soil structure can also increase the risks of landslides and other disasters in some places

– Other areas of the environment, such as where soil that erodes from a farm causes sedimentation in a river, or where soil contamination on one plot of land leaches and causes water pollution in a nearby water body

– Wildlife and living organisms that depend on soil, or that are indirectly impacted by issues like soil contamination (via leaching into aquatic environments for example)

 

Some more information on the potential effects of soil and land degradation …

 

According to wikipedia.org, ‘… soils hold the majority of the world’s biodiversity, and healthy soils are essential for food production and an adequate water supply. Soil degradation also impacts biological degradation, which affects the microbial community of the soil and can alter nutrient cycling, pest and disease control, and chemical transformation properties of the soil’

 

… ongoing soil degradation reduces global harvests by a third of a percent each year under conventional farming practices (blogs.scientificamerican.com)

 

About 60 percent of soil that is washed away [worldwide via soil erosion] ends up in rivers, streams and lakes, increasing the risks of flooding and intensifying water contamination from fertilizers and pesticides runoff (fewresources.org)

 

[soil loss from Erosion in Europe] impacts not just on food production but biodiversity, carbon loss and disaster resilience (theguardian.com)

 

Land degradation is already one of the major problems affecting the world

It is difficult to separate the effects of [a changing climate] and direct damage to soil

– sciencedirect.com

 

Soils play a key role in absorbing carbon and filtering water

Soil destruction creates a vicious cycle, in which less carbon is stored, the world gets hotter, and the land is further degraded.

– scientificamerican.com

 

The effect of [the] forms of land degradation [listed above by the FAO has been that] cereal production has so far been masked by the increasing levels of agricultural inputs that are used.

However, production of other crops, such as pulses, roots and tubers, has now begun to decline.

It is no coincidence that these crops are grown on land with low production potential, where rates of land degradation are highest.

– fao.org

 

You can read more about the effects and costs of land degradation and soil erosion at:

Effects & Costs Of Land Degradation (fao.org)

The economics of topsoil loss on a farm (farmprogress.com)

 

Economic Effects Of Soil & Land Degradation

In the US economy alone, some estimates of economic loss from soil and land degradation go into the billions of dollars (around 40 billion USD a year).

Some of the potential economic effects of soil and land degradation might be:

 

United States

… the American economy losing roughly $37 billion in productivity annually from soil loss (theweek.com)

 

Worldwide

The United Nations estimates that degradation of agricultural landscapes cost US$40 billion worldwide in 2014, not counting the hidden costs of increased fertiliser use and the loss of biodiversity and of unique landscapes … (ommegaonline.org)

 

The UNDP estimated that $42 billion in income and 6 million ha of productive land are lost every year due to land degradation (sciencedirect.com)

 

How To Prevent Land Degradation (& Potential Solutions)

When it comes to addressing land and soil degradation, the main points might be:

– It can either be prevented, or addressed after it’s happened

– The prevention of land and soil degradation might be the best solution, rather than have to address degradation after it’s happened. But, sometimes solutions have to be aimed at already degraded land/soil.

– Because the causes of land and soil degradation differ from region to region, each region and area of land needs it’s own individual strategy to address short and long term land degradation. Solutions should look to address the major causes of land and soil degradation in the area/region, or on an individual piece of land.

– Some types of degradation are reversible, and some aren’t.

– Some types of degradation might be reversible, but might involve a large and impractical time and money investment, making addressing the degradation unrealistic

– Addressing degradation might happen on different scales, from private and smaller plots of land, to funding large scale projects to restore significantly damaged and degraded soil and land 

 

Some specific solutions or prevention strategies for some of the main types and causes of land and soil degradation are …

 

– Water & Wind Soil Erosion

Ground cover, crop cover, and covering soil with organic matter can all protect soil from water and wind erosion

 

– Overgrazing

Rotating livestock on pasture and grazing land more effectively

 

– Intensive Agricultural Practices vs More Sustainable Farming Practices

Consider more sustainable farming practices that make good soil health and preserving soil fertility (that help keep nutrients in the soil, along with other goals) a priority.

Using organic fertilizer over synthetic fertilizer, using biological or organic pest control over synthetic pest control chemicals, crop rotation, no or low intensity tilling, drip irrigation, water and soil drains, and other practices might be considered.

Simply combining mor intensive and more sustainable farming practices is an option too, rather than choosing one over the other.

 

New farming practices like terraces and temporary “cover” crops have helped lower soil erosion by more than 40 percent over the past two decades (theweek.com)

 

Biological measures such as buffers, conditioner application in direct contact with the soil surface, crop residues using manure protect the soil from erosion.

Restoration of saline agricultural land can be achieved through recharge stabilization and reconstruction of saline land through fencing, retain remnant vegetation, revegetation, runoff interception earthworks, and water table lowering.

– ommegaonline.org

 

– Land Use Efficiency – Agricultural Productivity & Yield

Being more efficient with agricultural land and production means that agricultural input resources like land and soil are used more efficiently.

This depends on different factors, including but not limited to soil health and fertility, efficiency of the type of agricultural product being produced, agricultural practices used, and more.

Expanding on the efficiency of agricultural products point, plant based diets might be more land efficient than animal products (meat and dairy) according to some measurables, so food diets might be a factor too.

 

– Consider Alternate Forms Of Food Production Other Than Traditional Land Based Agriculture

We may also look at alternative forms of food production other than conventional agriculture, such as the potential benefits of lab grown meat, or the potential benefits of land based aquaculture, and of course open ocean fishing.

This cuts down on the need to use land and soil in some ways.

Some people think we can provide more food into the future with GMO technology, whilst others argue the downsides and disadvantages to it and prefer regenerative agriculture which focuses on organic and sustainable and holistic farming practices.

A mix or a decision between these methods of food production might have to be pursued in this instance

 

– Soil Contamination

Reduce air, water and general waste pollution

Consider farming practices that help reduce synthetic pesticide and fertilizer use

Ensure landfills are properly sealed so leachate doesn’t leak out and contaminate land/soil.

Limit and minimise illegal or damaging dumping of industrial waste, as well as hazardou waste. Ensure the proper management of this waste too

Manage oil/petroleum run off from roads and highways 

 

– Deforestation And Land Clearing

Consider how deforestation can be reduced, and consider how tree planting can be done effectively in the future

 

– Mining For Minerals, Metals & Fossil Fuels

More emphasis can be put on restoring mining sites.

But also, we can look at re-using and recycling metals and minerals already mined and being used above ground (potentially reducing the need to mine in some instances)

We can also look at moving towards renewable energy and electric cars if they mean we can eventually mine less fossil fuels from the ground.

 

– Other

Regulations and laws regarding the conservation and protection of land and soil

Economic incentives and support (including insurances and guarantees) for farmers, ranchers and those who own the land to ensure the health of the soil and land, without compromising their businesses and livelihoods, and whilst still meeting the demands of the population

More research into different aspects of sustainable but productive and effective agriculture (some types of organic agriculture might be part of the solution), and consider the impact of subsidies for agricultural business owners to help them implement it

Consider how local communities can be incentivized to conserve soil and land health in certain regions

Have more public awareness about the different aspects soil and land health – such as soil fertility, soil health, soil structure, beneficial microorganisms, soil pollutants, and so on

Consider performance objectives for different soils and land in different regions and zones

One of the best ways to prevent land degradation worldwide in the future would be to better map the world’s land and soil (with satellites and other technology), and track the impact of different factors (like deforestation, farming, weather etc.) on this land and soil. An example of how this is currently being done is the Global Land Outlook.

Look at the impact severe and changing weather events are having on soil health

Address indirect factors like lifestyle choices, overpopulation, diets, etc. that can impact soil health

 

… sub-Saharan Africa, south Asia, the Middle East and north Africa will face the greatest challenges [in the future] unless the world sees lower levels of meat consumption, better land regulation and improved farming efficiency (theguardian.com)

 

Some potential solutions for restoring, recycling or treating land and soil might be …

(However, these approaches can be time consuming for farmers, as well as financial and business risk, and in some cases decrease yields/productivity, and also profits.)

 

– Restoring Damaged Land/Soil

Depending on the cost and time expenses involved …

Soil that has been contaminated can be aerated and treated.

Additionally, top soil that has been eroded can be renewed (slowly).

Soil that is too acidic can be rebalanced.

Land that has been desertified by weather, mining or other factors can be restored in various ways.

Bioremediation and phytoremediation are two examples of new/developing soil restoration technology.

 

From FAO.org:

Land reclamation frequently requires inputs which are costly, labour-demanding or both.

The reclamation projects in salinized and waterlogged irrigated areas demonstrate this fact clearly.

The cost of reclamation, or restoration to productive use, of degraded soils is invariably less than the cost of preventing degradation before it occurs.

 

– Recycling Damaged Land/Soil

Instead of restoring the land, it might be recycled with an end use in mind.

For example, former mining sites might become sites for solar panels and wind farms, or land fill sites might become parks.

 

– Specifically Treating/Managing Soil Contamination

Wikipedia.org outlines the different methods for treating soil contamination.

The basic process might involve:

– excavation of contaminated soil, and taking away to a disposal sites

– aerating soil at the contaminated site

There’s then a range of remediation treatments and treatments such as thermal remediation, bioremediation, extraction and stripping of contaminants, containment, phytoremediation, mycoremediation, self-collapsing air microbubbles and surfactant leaching

 

– Specifically Reducing Likelihood Of Desertification

soils.org lists a list of land management practices that might be implemented to reduce the likelihood of desertification. They include reducing the number of grazing animals, rotating animals to new grazing areas more often, using conservation tillage and no till where possible, using low intensity and high diversity crop rotations, maintaining perennial vegetation, using irrigation properly to increase ground cover, and using selective or staggered tree harvest techniques rather than clear-cutting

 

Summary Of Practical Steps To Addressing Land & Soil Degradation

Some refined practical steps for addressing soil and land degradation might involve:

1. Attempt to prevent land and soil degradation in the first place

 

2. If prevention isn’t an option, identify the type of soil or land degradation taking place in a region, or on an area of land

 

3. Understand that each geographic region and area of land in the world might have a different set of causes for land and soil degradation

There are some good images at fewresource.org – these images show the major types of land degradation, and soil loss by region.

As an example, overgrazing is a major cause of land degradation and soil erosion in Africa.

Comparatively, industrial agricultural practices are the major cause of land degradation and soil erosion in North America.

We see deforestation has played a major role in South America.

 

4. Identify the primary and secondary causes of each type of land and soil degradation happening on an area of land

[For example, if industrial agriculture is a major cause of soil loss, practices like planting cover crops, reduced tillage, crop rotation, rotational grazing, and other practices might be implanted to better conserve soil.]

 

5. Custom design both a short and long term strategy based on the causes of each type of land and soil degradation

Once causes have been identified in an area, prevention strategies and solutions can be based around those causes.

As an example, conventional agricultural practices in North America might involve using industrial machinery that involve heavy tilling of the soil, and application of agricultural chemicals like fertilizer and pesticides that erode soil health/fertility steadily over time (aside from the physical loss of topsoil – loss of soil health is a form of erosion too).

To combat this, more focus may need to be placed on soil conservation practices and sustainable farming practices.

There are many examples of sustainable farming practices, including but not limited to cover crops, zero or reduced tillage, crop rotation, rotational grazing, organic fertlizer, and better drainage.

Several case studies show that sustainable farming practices can reduce soil erosion and reduce erosion related financial losses for decreased yields for example.

 

Reversible vs Non Reversible Land Degradation

In terms of being able to reverse the effects of land degradation, there might be three categories:

– Reversible

– Reversible, but it comes at a great time, cost or difficulty expense (such as not being able to be done at scale)

– Not practically reversible

 

From FAO.org:

The effects of water and wind erosion are largely irreversible

Although plant nutrients and soil organic matter may be replaced, to replace the actual loss of soil material would require taking the soil out of use for many thousands of years, an impractical course of action.

In other cases, land degradation is reversible: soils with reduced organic matter can be restored by additions of plant residues, degraded pastures may recover under improved range management.

Salinized soils can be restored to productive use, although at a high cost, through salinity control and reclamation projects.

In other cases, the land can only be restored by taking it out of productive use for some years, as in reclamation forestry.

 

Rehabilitating & Re-Greening Land (With Examples)

Countries like China (and Ethiopia, which has rehabilitated 7m hectares (17m acres) – theguardian.com) have already undertaken mass land restoration projects on land that was severely eroded.

Although some projects can be lower cost and more straightforward, some projects are  complex, expensive, have unique challenges and limitations, and can take decades to see long term results.

Governments and for profit companies may have the largest role in deciding how much of a role land restoration projects can play in our future.

Read more about restoring and re-greening land at scale in different countries in this guide.

 

Sources

1. https://en.wikipedia.org/wiki/Land_degradation

2. https://en.wikipedia.org/wiki/Land_use

3. https://visual.ly/community/infographic/environment/polluted-soil

4. https://www.metropolitantransferstation.com.au/blog/negative-effects-of-improper-waste-management

5. https://www.explainthatstuff.com/land-pollution.html

6. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/land-degradation

7. http://www.fao.org/3/v4360e/V4360E03.htm 

8. https://www.theguardian.com/environment/2017/sep/12/third-of-earths-soil-acutely-degraded-due-to-agriculture-study 

9. https://apps.who.int/iris/bitstream/handle/10665/177155/Synt_R_5.pdf?sequence=5&isAllowed=y 

10. https://www.sciencedirect.com/science/article/pii/S0143622814002793 

11. https://www.un.org/popin/fao/centasia/faotext3.htm 

12. http://www.fao.org/3/v9909e/v9909e02.htm 

13. http://www.fao.org/soils-2015/news/news-detail/en/c/275770/ 

14. https://www.ommegaonline.org/article-details/Restoration-of-Degraded-Agricultural-Land-A-Review/1928 

15. https://www.globalagriculture.org/report-topics/soil-fertility-and-erosion.html

16. https://www.farmprogress.com/soil-health/economics-soil-loss 

17. https://theweek.com/articles/554677/america-running-soil 

18. https://www.scientificamerican.com/article/only-60-years-of-farming-left-if-soil-degradation-continues/ 

19. https://blogs.scientificamerican.com/observations/to-feed-the-world-sustainably-repair-the-soil/ 

20. https://www.fewresources.org/soil-science-and-society-were-running-out-of-dirt.html

21. https://en.wikipedia.org/wiki/Environmental_impact_of_agriculture

22. http://www.earthsave.org/environment.htm

23. https://www.bbc.com/future/bespoke/follow-the-food/why-soil-is-disappearing-from-farms/

24. https://www.soils.org/files/sssa/iys/november-soils-overview.pdf

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