Global Land Degradation Practice Flashcards

80 vocabulary cards based on a lecture transcript regarding global land degradation, including definitions of key terms, drivers, ecosystem impacts, and human consequences.

Land degradation (IPCC definition)

A negative trend in land condition caused by direct or indirect human processes, expressed as a long term reduction or loss of biological productivity, ecological integrity, or human evaluative humans.

Land degradation (IPFBES definition)

Processes that drive the decline in biodiversity, ecosystem functions, and services, including the degradation of all terrestrial ecosystems.

Degraded land (IPFBES definition)

Land in a state that results from persistent decline or loss of biodiversity and ecosystem functions.

IPFBES

The acronym for the Intergovernmental Science Policy Platform on Biodiversity Ecosystem Services, an independent panel providing scientific assessments on biodiversity.

IPCC

The Intergovernmental Panel for Climate Change, a body out of the UN that assesses science related to climate change to inform governments and policymakers.

UNCCD

The United Nations Convention To Combat Dessertification, established in the 1990s as the only legally binding framework to address drought and desertification.

Global Land Outlook

A massive publication by the UNCCD, the second edition of which focuses on pathways to revert and restore degraded lands.

Summary for Policymakers

A big picture distillation found at the front of large global reports, bringing together knowledge from academic, stakeholder, and policy communities.

Planetary boundaries

A set of nine boundaries used to define a safe operating space for humanity, four of which have already been exceeded.

Safe operating space

A concept defining the environmental limits within which humanity can safely function; breaches are linked to human induced desertification and land degradation.

Anthropogenic landscapes

Landscapes that are human-created or heavily influenced by human activity, such as urban environments.

Ground zero of land degradation

Unsustainable consumption choices and consumerism demand that drive destructive processes like urbanization and agriculture.

Status of global soils

The UN estimates that $33\%$ of our soils globally are already degraded.

Land lost per year

At least $100,000,000\,hectares$ of healthy land are now lost each year, which is roughly twice the area of Spain.

Agriculture as a driver

The dominant sector driving land degradation, fueled by money and consumerism for a growing global population.

Per capita calorie intake change

Since 1961, per capita calorie intake has increased by $32\%$.

Dietary composition shifts

Since 1961, meat and vegetable consumption has more than doubled, and dairy product consumption increased by a factor of $1.2$.

Material footprint by income

Upper middle income countries have the highest absolute consumption, while high income countries have the highest per capita footprint of consumption.

Deforestation

A complete change in land use, often involving the clearing of trees for crops, logging, or plantations.

Forest degradation

A reduction in biomass, productivity, or benefits from a forest that does not necessarily involve a move to a non-forest land use.

Shifting agriculture

A process where forest areas are cleared for a patch of agriculture until productivity declines, then the process moves to a new area.

Commodity driven deforestation

Deforestation specifically to produce crops for global trade, such as soy or palm oil.

Forest fragmentation

A process that normally precedes complete deforestation and leads to degradation and defounation.

Defaunation

The loss of animal species within a forest ecosystem, often linked to fragmentation and degradation.

Intact forest status

Globally, less than $30\%$ of forests are still intact.

Old growth forest status

Less than $40\%$ of forest area is estimated to contain old growth forest.

Global natural forest decline

According to the forest resources assessment, the global area declined by $2,400,000\,kilometres$ from the 1990s to 2015.

Forestry and forest loss

The predominant reason for forest loss in parts of the Northern Hemisphere, Europe, and China.

Tree canopy latitudinal trends

There is a net gain in tree canopy at higher and more southern latitudes, but a decrease at lower latitudes.

Above ground carbon loss

The loss of carbon stored in trees due to clearing, estimated at $972,000,000\,tons$ of potential sequestration by 2050 if lost trees had remained.

Below ground carbon stock

The carbon stored in the soil, which is affected by logging, fire, and reforestation with non-native trees.

Clear cutting impact on soil carbon

Soil disturbance accompanied by clear cutting reduces soil carbon on average by $10\%$.

Soil organic matter (SOM)

A complex substance in soil that includes organic carbon and supports soil structure and health.

Soil organic carbon (SOC)

A component of soil organic matter that supports structure, improves root penetration, and provides nutrients.

European soil carbon reservoir

European soils contain around $75,000,000,000\,tonnes$ of organic carbon.

Splash erosion

A process where rain hits bare soil surfaces and dislodges soil bits through splashes.

Sheet erosion

A process where big areas or sheets of soil are dislodged and swept away by water.

Rill erosion

The formation of small channels or tracks in the soil as water moves through the landscape.

Gully erosion

The formation of large depressions and channels in the landscape as water runs through soil, which is very difficult to restore.

Extinction drivers

Destruction and fragmentation of forests is the biggest driver of extinctions, particularly vertebrate extinctions.

IUCN red list

A list identifying threatened or declining species; deforestation increases the likelihood of species being listed.

Peatlands

Wetland areas where dead plant matter and carbon accumulate in waterlogged soils due to slow rates of decomposition.

Peatland degradation

Caused primarily by drainage for human use; degraded peatlands emit CO2 and are at a much higher risk of fire.

Fens of East Anglia

A region in the UK where peatlands have been reduced from $3,400\,kilometres^2$ to only $10\,kilometres^2$.

Temperate grasslands

One of the most endangered biomes in the world, often converted for commodity demand like corn and soybeans.

Tropical grassy biomes

Grasslands in the tropics that harbor high biodiversity, including half the vascular plant richness of tropical forests.

Silviculture

The planting of trees for commercial purposes, which is a major driver of degradation in tropical grassy biomes.

Brazilian Serrado

A tropical grassy ecosystem and one of five South American biodiversity hotspots currently threatened by eucalyptus and pine monocultures.

Albedo effect

The high reflectance properties of natural grasslands that provide temperature lowering benefits, outweighing carbon fixing from new forests.

Pastoralists

Approximately $100,000,000$ to $200,000,000$ people with low-income subsistence livelihoods who rely on range lands for grazing livestock.

Great Yellow Bumblebee

One of the rarest bumblebees in Great Britain, which has declined by $80\%$ due to the loss of natural grassland areas in Scotland.

Arable land

Land used for agricultural crop production.

Aridity

The largest singular pressure for agricultural systems, affecting approximately $40\%$ of global cropland.

Conventional agriculture

Intensive management involving frequent tillage, no cover crops, and no landscape barriers, leading to high soil loss.

Conservation agriculture

An approach using wind breaks, cover crops, and reduced tillage to keep soil within the arable landscape.

Tillage erosion

The movement of soil down a slope caused by frequent plowing and disturbing of the soil.

Harvest erosion

The loss of soil when it sticks to crops, such as tubers or root species, during extraction from the ground.

Topsoil loss statistics

Around half of the total global topsoil has been lost in the last $150\,years$.

Water clarity impact

Sedimentation from soil erosion reduces light filtration and food availability in aquatic environments.

Algal blooms

A consequence of sedimentation in waterways; for example, one event in Lake Victoria caused the loss of over $400,000\,fish$.

Marine deutrophication

Excessive nutrient enrichment in marine environments, sometimes caused by phosphorus rich dust blown from agricultural fields.

Financial cost of sedimentation (Brazil)

Processing plants for hydropower in Brazil spend approximately $9,800,000\,US\,dollars$ a year to manage sediment.

River dredging costs (Europe)

The annual cost of river dredging across Europe is approximately $\text{ } 900,000,000\,Euros$.

Wind erosion dust volume

Globally, wind erosion releases $5,000\,teragrams$ of mineral dust into the atmosphere.

Radiative forcing

Climate forcing caused by mineral dust in the atmosphere, which exacerbates climate change.

Snow pack duration (Colorado)

Increase in dust has reduced snow pack duration in the Colorado River Basin by $31$ to $51\,days$ a year.

Soil organic carbon stabilization efficiency

Root carbon inputs have an efficiency five times greater than above ground carbon for stabilizing SOC.

Chemical recalcitrance

The resistance of compounds like lignin and superin in roots to microbial decomposition.

Lignin and Superin

Compounds found in roots that contribute to the persistence of root-derived carbon in the soil.

Physicochemical protection

The association of root-derived carbon with soil minerals to form organo mineral complexes that prevent microbial degradation.

Organo mineral complexes

Formations between soil minerals and organic matter that enhance the stability of carbon in the soil.

Physical protection of carbon

The action of soil aggregates and roots in physically shielding organic matter from microbial access.

Heavier grazing impact

Higher stocking densities in grazing landscapes lead to greater loss of organic soil carbon and increased soil compaction.

Runoff increase from heavy grazing

Heavy grazing promotes an increase in runoff by up to $117\%$ compared with rotational or light grazing.

Soil salinisation

A degradation process in agricultural land that can result in the land becoming completely unfit for agriculture.

2050 Food security projections

Land degradation is expected to reduce crop yields by $10\%$ and increase food prices by $30\%$.

Indigenous foods

Traditional foods whose declining use is driven by land and environmental degradation, impacting cultural identity.

Land tenure

The legal regime in which land is owned or used; insecure tenure often reduces incentives for land conservation.

GDP loss and conflict

Every $5\%$ loss of GDP caused by degradation is associated with a $12\%$ increase in the likelihood of violent conflict.

DALYs

Disability life adjusted years; a measure of the health burden per $1,000\,people$ per year as a result of a degraded environment.

Psychosomatic stress recovery

Recovery from stress and mental illness is found to be significantly higher in people exposed to natural landscapes compared to urban ones.