Land cover change

Land cover is what physically covers the land: forest, grassland, cropland, water, ice or built-up areas. Land use is what people use it for. A forest might be used for timber, conservation or cultural purposes.

Humans have transformed land cover on a massive scale. Forests cover about 31% of the world's land area. The UN Food and Agriculture Organization estimated that around 10 million hectares of forest a year were cleared between 2015 and 2020, although replanting and natural regrowth offset part of the loss.

Drivers of deforestation include expansion of agriculture (cattle pasture, soy and palm oil), logging, mining, infrastructure and urban growth. Underlying drivers include population growth, global demand for commodities, poverty and weak governance.

Consequences include loss of biodiversity, soil erosion, changes to local rainfall and water cycles, and the release of carbon dioxide. Forests act as carbon sinks, so clearing them contributes to climate change.

In Australia, large areas of native vegetation have been cleared since 1788, particularly in the wheat–sheep belt and parts of Queensland. Clearing has been linked to dryland salinity, erosion and loss of habitat. Land clearing laws differ between states and remain debated.

Remote sensing allows geographers to monitor change. The Landsat satellite program has collected imagery since 1972, allowing comparisons over decades. Analysing changes in pixel colour or vegetation indices reveals clearing, regrowth and urban expansion.

Responses include protected areas, reafforestation, sustainable certification schemes, payments for ecosystem services and Indigenous land management. First Nations-managed lands, including Indigenous Protected Areas in Australia, make a major contribution to conservation.