Human Activity Altered 70 Percent of Earth’s Land, Degraded 40 Percent of It

Humans have had an unprecedented impact on land – with vast consequences for climate change, food systems and biodiversity, a major new UN report concludes.

It says that human activities have already altered 70% of the Earth’s land surface, degrading up to 40% of it. Four of the nine “planetary boundaries” – limits on how humans can safely use Earth’s resources – have already been exceeded.

Food systems – a catch-all term to describe the way humans produce, process, transport and consume food – are the largest culprit when it comes to land degradation, the report says. They account for 80% of deforestation, 29% of greenhouse gas emissions and the leading share of biodiversity loss.

The degradation of land is perpetuated by steep inequalities, it adds. It notes that 70% of the world’s agricultural land is controlled by just 1% of farms, primarily large agribusinesses.

The report, from the United Nations Convention to Combat Desertification (UNCCD), urges world leaders to adopt a “crisis footing” to solve land degradation. The authors warn that “at no other point in modern history has humanity faced such an array of familiar and unfamiliar risks and hazards”.

It projects that, if “business as usual” continues to 2050, an additional 16m square kilometres (km2) – an area almost the size of South America – could be degraded.

By contrast, if the world prioritises land protection and restoration, it could lead to the creation of 4m km2 of new “natural areas” by 2050, with benefits for tackling climate change and biodiversity loss.

In this article, Carbon Brief walks through five key takeaways from the UN’s milestone land report.

What Is the UN Land Report?

The new report is by the United Nations Convention to Combat Desertification (UNCCD). The Convention is the only legally binding framework that addresses desertification and the effects of drought and has 197 parties. It was established in 1994, via a direct decision at the 1992 Rio Earth Summit, which also gave the world the UN Framework Convention on Climate Change and the Convention on Biological Diversity.

The UNCCD is focused on the rehabilitation, conservation and sustainable management of land and water resources and is the “custodian” for Sustainable Development Goal Target 15.3, which aims to:

“By 2030, combat desertification, restore degraded land and soil, including land affected by desertification, drought and floods, and strive to achieve a land degradation-neutral world.”

Five years in the making, the second edition of the Global Land Outlook (GLO2) analyses future land scenarios and the contributions of land-based restoration to climate mitigation, biodiversity protection, health and the UN Sustainable Development Goals. (The first edition, published in 2017, mostly outlined the drivers of desertification.)

The report was developed in partnership with 21 different organisations and cites more than a thousand publications. Partners include the UN’s Food and Agriculture Organization (FAO) and the Convention on Biological Diversity (CBD), as well as the Indonesia-based Center for International Forestry Research (CIFOR) and Cape Town-based climate consultancy C4 EcoSolutions.

The report comes just two weeks before the UNCCD’s 15th “desertification COP” (COP15), scheduled to take place in Abidjan, Ivory Coast from 9 to 20 May this year.

The UN hopes COP15 will serve as “a key moment in the fight against desertification, land degradation and drought”, as parties step into what it describes as the UN Decade on Ecosystem Restoration from 2021 to 2030. This aims to prevent, halt and reverse ecosystem degradation “on every continent and in every ocean”.

Governments are expected to “build on the report’s findings” and offer a concrete response to the interconnected challenges of land degradation, climate change and biodiversity loss, the UN says.

The report is split into three parts.

The first part presents the many challenges to land systems: from biophysical drivers in the Earth system to social and economic systems and their demands on land.

The second part assesses land restoration activities and practices globally.

The third part assesses the effectiveness and feasibility of global, national and financial commitments to restoration. It sets out three scenarios through 2050: “business as usual”, a “restoration scenario” and a “restoration and protection scenario”.

The report was welcomed by UN Biodiversity chief Elizabeth Maruma Mrema (who was interviewed in depth by Carbon Brief last month), who called it a “must-read for the biodiversity community”. In a statement, she said:

“The future of biodiversity is precarious. We have already degraded nearly 40% and altered 70% of the land. We cannot afford to have another ‘lost decade’ for nature and need to act now for a future of life in harmony with nature. The GLO2 shows pathways, enablers and knowledge that we should apply to effectively implement the post-2020 Global Biodiversity Framework.”

Here, Carbon Brief presents five key takeaways from the GLO2 and their significance for the world’s climate and biodiversity.

1: Humans Have Already Transformed More Than 70 Percent of the Earth’s Land Area

Humans have already altered more than 70% of the Earth’s land area from its natural state, the report says.

This has caused “unparalleled environmental degradation” and contributed “significantly to global warming”, according to the report.

Because of human activity, an estimated $44tn – roughly half the world’s annual economic output – is being put at risk by the depletion of natural resources, the report says.

These resources “underpin human and environmental health by regulating climate, water, disease, pests, waste and air pollution, while providing numerous other benefits such as recreation and cultural benefits”, the report states.

It cites analysis finding at least 20% of the global land surface is now degraded – an area the size of the African continent. However, it adds that this estimate is “conservative” and notes that other assessments put the proportion of land degraded at between 20 and 40%. (The report says land degradation can happen “in many ways”, including through the loss of trees from forests, the conversion of grasslands to croplands and the over-exploitation of water and soil in drylands.)

Degradation is “particularly acute” in dryland regions, which are today home to one in three people, the report adds. (Drylands is a collective term for water-scarce parts of the world, including arid, semi-arid and dry sub-humid areas. The UNCCD’s definition of desertification is land degradation in these areas.)

It says that of the nine “planetary boundaries” – limits on how humans can safely use Earth’s resources – four have already been exceeded: climate change, biodiversity loss, land use change and geochemical cycles (including, for example, the carbon cycle).

The graphic below shows the four planetary boundaries that have been exceeded in red. (Many more are at a high risk of being exceeded, as Carbon Brief has previously reported.)

The report says the breaches of the planetary boundaries are “directly linked to human-induced desertification, land degradation and drought”. It adds:

“If current trends persist, the risk of widespread, abrupt, or irreversible environmental changes will grow.”

Looking specifically at biodiversity loss, the report says populations of mammals, birds, amphibians, reptiles and fish decreased by an average of 68% between 1970 and 2016.

It adds that, in tropical central and South America, populations fell by 94% – “primarily due to land use change, largely the conversion of grasslands, savannahs, forests, and wetlands for agriculture and extractive industries”.

On land-use change, the report says that 5-10m hectares of forest were razed every year between 2000 and 2015, leading to a total global loss of 125m hectares – an area twice the size of France.

It adds that “hidden in the numbers is the loss of biodiverse and carbon-rich tropical forests”, which “have been offset by an almost fivefold increase in the rate of expansion of temperate forests”.

2: Food Systems Are Responsible for 80 Percent of Deforestation, 29 Percent of Greenhouse Gas Emissions and Are the Single Largest Cause of Biodiversity Loss on Land

“More than any other activity”, the report reads, modern agriculture is responsible for “alter[ing] the face of the planet”. At least 40% of the Earth’s land surface is dedicated to agriculture, and more than half of these lands are degraded.

Large-scale and industrial agricultural operations generate high levels of greenhouse gas emissions – 29% of the world’s total. Much of these emissions are the result of deforestation and other land-use change. According to the report, 80% of global deforestation is caused by agriculture, which also accounts for 70% of the world’s freshwater use.

Thus far, regulations have not been sufficient to protect ecosystems from agricultural expansion, the report says. From 2013-9, more than two-thirds of agriculture-driven tropical forest clearance was carried out “in violation of national laws or regulations” – an area totalling 32m hectares, approximately the size of Norway.

Cattle, palm oil and soya are three of the largest culprits for this illegal deforestation, which is driven by “short-sighted national development priorities”, lax enforcement of existing regulations and “ultimately, consumer demand in developed countries”, the report states.

In addition, land degradation by food systems is not limited to deforestation. Agricultural expansion and climate change pose the “greatest threats” to grasslands, which make up more than two-thirds of the land being converted to cropland in wet regions of the planet.

Below-ground biodiversity and soil health have also “been largely neglected” by the transition to industrial agriculture, with serious ramifications. The report states:

“While agricultural intensification can increase yields in the short term, unless done in a sustainable manner, it tends to cause high levels of land and soil degradation and contamination. Faced with long-term declines in productivity and water scarcity, farmers paradoxically resort to the increased use of harmful agrochemicals and inefficient irrigation systems.”

With the industrialisation of agriculture has come the expansion of large-scale agribusinesses. Just 1% of the world’s farms control more than 70% of agricultural land, the report notes. In contrast, 80% of farms comprise less than two hectares, totalling just 12% of the total. At the same time, the report says, family farms are “key sources of the diverse diets that provide food and nutrition security for local communities”.

Furthermore, these small-scale farms are more suited for agroecological and other regenerative farming practices. The report lays out several case studies of communities where a shift towards “nature-positive” food production has resulted in the restoration or maintenance of ecosystems.

For example, the Campesino a Campesino movement – a grassroots ecological farming collective in Cuba – has helped farmers boost production without the use of agrochemicals, which are scarce and expensive in the country.

The report says that a “logical first step” towards reducing the impacts of agriculture would be a transition towards more plant-based diets. It notes that almost 80% of agricultural land is used to raise livestock, “while providing less than 20% of the world’s food calories”.

The report also calls for elimination of subsidies for harmful farming practices. More than $700bn of subsidies are paid out each year, the report says, but only 15% of this funding “positively impacts natural capital, biodiversity, long-term job stability and livelihoods”.

3: ​​Protecting and Restoring Ecosystems Could Provide More Than a Third of the Land-Based Climate Action Needed to Meet Global Warming Goals

Protecting and restoring natural environments could provide more than a third of the land-based climate action needed between now and 2030 to meet global warming goals, the report says.

A section of the report is dedicated to the role that land can play in “boosting climate action”.

It notes that the world has set a goal to limit global warming to well-below 2C by 2100 – with an aspiration of keeping temperatures at 1.5C – under the 2015 Paris Agreement.

Protecting and restoring land “reduces emissions and sequesters carbon”, the report says. It cites analysis finding that this could provide a third of the “cost-effective, land-based climate mitigation needed between now and 2030” to meet the Paris goals.

In addition to reducing emissions, land-based climate solutions could also help the world adapt to the impacts of warming, the report adds.

It says that “effective management and expansion of conserved and protected areas” and “ecological restoration or rewilding of biodiversity and well-functioning ecosystems” could play a role in climate adaptation.

The report also notes that, while the land and ocean have historically removed over half of the CO2 released by humans, the rate of removal “is now declining”. It continues:

“If land degradation continues unabated, this could potentially trigger a reversal from land being a net sink to being a net source.”

(As the first part of the Intergovernmental Panel on Climate Change’s (IPCC) sixth assessment report explains (pdf): “…while natural land and ocean carbon sinks are projected to take up, in absolute terms, a progressively larger amount of CO2 under higher compared to lower CO2 emissions scenarios, they become less effective, that is, the proportion of emissions taken up by land and ocean decrease with increasing cumulative CO2 emissions. This is projected to result in a higher proportion of emitted CO2 remaining in the atmosphere.”)

The degradation of land is already contributing to climate change, the report adds.

CO2 emissions from land largely come from deforestation and the draining and burning of peatlands, as well as from the degradation of soils due to agriculture, it says.

It cites a study finding that, throughout history, farming has released roughly 116bn tonnes of carbon into the atmosphere, with the rate of loss “increasing dramatically” in the last 200 years.

Meanwhile, emissions of methane and nitrous oxide, two potent greenhouse gases, largely come from nitrogen fertiliser use and the rearing of livestock, respectively, the report says.

In addition to land degradation driving climate change, the impacts of warming are further contributing to the decline of land, the report notes. It says:

“Hotter temperatures, along with longer, more intense droughts, wildfires, and extreme rainfall events, weaken ecological integrity and resilience in both managed and natural land systems.”

Because of human-caused climate change, “many forests and grasslands around the world are now more susceptible to pest and disease outbreaks” and crop yields have been “reduced”, the report says.

Climate change poses a particular threat to peatlands and permafrost, which “store huge amounts of greenhouse gases and provide essential services and unique habitats for many species”, according to the report.

It says that climate change is increasingly causing peatlands to “dry out” and causing permafrost to thaw.

Further degradation of these ecosystems could create “feedback loops” that could “surpass climate thresholds and accelerate global warming far beyond human control”. (For more on climate tipping points, read Carbon Brief’s dedicated explainer.)

4: Land Degradation Threatens Marginalized Communities the Most — But These Groups Have Much to Contribute to Ecosystem Restoration and Protection

More than 3 billion people are already living with the impacts of desertification, land degradation and drought, the report says. These are “mostly poor rural communities, small-scale farmers, women, youth, Indigenous peoples and other at-risk groups”.

These historically marginalised groups “are often the most exposed” to the risks associated with land degradation.

But land restoration measures that are not responsibly designed “could risk disenfranchising the most vulnerable and threaten their health, homes and livelihoods”, the report warns.

For example, expanding protected areas could have the unintended consequence of threatening Indigenous peoples who “legitimately occupy or claim these lands through customary systems that rarely are legally documented”.

Indigenous peoples represent around 6% of the global population, yet they act as stewards for at least 38m km2 – an area spread out across 87 countries and spanning all six inhabited continents. In total, Indigenous peoples have tenure rights over about one-quarter of the Earth’s surface, and 40% of intact ecosystems and protected areas.

However, Indigenous peoples have also been frequently forced from their lands and subjected to discrimination, with the result that “their fundamental rights and freedoms are often severely curtailed”, the report says. It discusses the Land Back movement – a growing push for these communities to reclaim their ancestral lands. It states:

“The Land Back movement offers many opportunities for the restoration of traditional, regenerative land and water management practices, which could be applied throughout large parks, public lands, and protected areas. The movement is aligned with global campaigns to protect biodiversity, expand Indigenous management of protected areas and restore natural capital to mitigate and adapt to climate change.”

In the US, for example, the return of forest management duties to the Confederated Salish and Kootenai Tribes in Montana in 1988 “led to increased species diversity and a healthier tree age distribution”. As a result, the forests on the reservation were “less prone to wildfires while providing better wildlife habitat and higher water quality compared to land managed by the US Forest Service”.

The report notes that “despite being a major store of carbon with great potential for achieving environmental and development goals”, rangelands – areas used for grazing or hunting animals – are “often neglected” in discussions of land restoration.

Around 500 million people around the world are pastoralists – typically nomadic livestock-keepers who occupy rangelands around the world. Their management of these ecosystems is “now threatened by climate change and mobility restrictions, as well as appropriation and encroachment”.

The report cites examples of collective land tenure and management from several continents as one potential method for maintaining pastoralist lifestyles.

Although the 2030 Agenda for Sustainable Development calls for the protection and restoration of ecosystems, the agenda contains a “critical void”, the report says – “a lack of attention to the social and political dimensions of land restoration initiatives”.

It notes that historically, programmes that have been “gender blind” have exacerbated existing gender inequalities, “with women’s access to land and natural resources further restricted, women’s voices and agendas undermined and their work burden increased”.

The report calls for “inclusive decision-making” processes to ensure equitable outcomes for marginalised communities. It says:

“Addressing past and ongoing injustices will help create a robust and enduring dynamic for future equity and sustainability through improved land management, social cohesion and more responsible governance.”

5: The World Faces a Stark Choice Between Protecting and Restoring Land and “Business as Usual”

The report outlines three scenarios for land from 2015 until 2050:

• A “business as usual” baseline scenario, where current trends in land and natural resource degradation are projected to continue through to 2050;
• a “restoration scenario”, where restoration is carried out on a “massive scale” and 5bn hectares of land (50m km2) are restored by 2050, through measures such as low- or no-till farming, agroforestry and silvopasture, improved grazing management, grassland rehabilitation, forest plantations and assisted natural regeneration;
• a “restoration and protection scenario”, where vital ecosystems are specifically restored and protected, in addition to other efforts.

The figure below shows these restoration scenarios for future land health, relative to the current trajectory of land commitments.

If the world proceeds at the pace of “business as usual”, the report estimates that by 2050, land almost the size of South America (16m km2) would show continued degradation.

In total, an additional 69bn tonnes of carbon would be emitted because of land-use change and soil degradation – divided between soil organic carbon (32bn), vegetation (27bn) and peatland degradation/conversion (10bn). Per year, these emissions “represent 17% of current annual greenhouse gas emissions”, the report says.

Agricultural yields might continue to rise, but land degradation will curb increases and so will associated risks of drought and water scarcity, the report says. An agricultural slowdown could be especially acute in the Middle East, north and sub-Saharan Africa and Latin America, brought on primarily by the loss of organic soil carbon and soil’s ability to hold water and nutrients. Sub-Saharan Africa would be the worst affected, under this scenario.

Nature and biodiversity suffer the most under business as usual, the report says. Natural areas the size of India’s landmass would need to be cleared to feed a hungry world, with food demand projected to rise 45% between 2015 and 2050.

As a result, the report warns that “business as usual is not an option”.

Under the “restoration” scenario – where 16m km2 of cropland, 22m km2 of grazing land, and 14m km2 of natural areas are restored – 11% of biodiversity loss is averted, the report estimates.

Crop yields increase by 5-10% in most developing countries – especially in Latin America, north and sub-Saharan Africa and the Middle East – and food price spikes are limited. In rain-fed croplands, soil water holding capacity would increase by 4%,

Because of gains in soil carbon and reduced emissions, soil carbon stocks would be 55bn tonnes larger in 2050 compared to the baseline. Russia, eastern Europe, Central Asia and Latin America will see the largest gains, while the “worst losses” will be averted in sub-Saharan Africa.

The “restoration and protection” scenario in the report envisages a world where land protection measures are expanded to cover close to half of the Earth’s land surface by 2050 – a threefold increase on the current coverage.

If this takes place, an additional 83bn tonnes of carbon are stored compared to the baseline, the report says:

“Avoided emissions and increased carbon storage would be equivalent to more than seven years of total current global emissions.”

However, this scenario would also mean escalating food prices – particularly in south and south-east Asia, where the report says a shortfall of agricultural land is “already impacting food security”.

To date, more than 115 countries have committed to restore close to 10m km2 of degraded land, be it in their climate plans, national biodiversity plans, voluntary pledges to the Bonn Challenge or otherwise. Today’s commitments, however, are “still insufficient to realise a nature-positive and climate-resilient future” and “must be backed by clear action plans and sustained financing”, the report says.

The figure below provides a snapshot of the extent of land countries have voluntarily pledged to restore under the Nationally Determined Contributions (NDCs) under the Paris Agreement, Land Degradation Neutrality (LDN) pledges to the UNCCD, National Biodiversity Strategies and Action Plans (NBSAP) under the Convention on Biological Diversity and commitments to the Bonn Challenge.

These commitments are estimated to cost between $305bn and $1.7tn – significant, but “far less than the amount of subsidies currently provided to the agriculture and fossil fuel industries”, says the report. The figure below lays out the estimated cost ranges for most restoration measures.

The report says that to expect most developing countries to meet these costs would be “unrealistic and unfair” and they would need “extra-budgetary support in the form of investments, development aid (for trade), debt relief, or other financial instruments”. It adds:

“Countries that are disproportionately responsible for the climate, biodiversity and environmental crises must do more to support developing countries as they restore their land resources and make these activities central to building healthier and more resilient societies.”

The report observes that “gender-responsive” land restoration – illustrated in the figure below – is an “obvious pathway” to reduce poverty and hunger.

It also finds that community-based restoration initiatives “tend to be the most successful” and that Indigenous peoples and local communities “represent a vast store of human and social capital that must be respected and embraced” to restore the planet.