Monitoring changing land-use patterns is a key area of assessing the impact of human activity on the planet and the potential effects of our actions on climate change. It is an essential area of study for climate scientists. However, the complex patterns and global changes have proved difficult to monitor accurately.

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Now though, a team for researchers, based in Leipzig, Germany has created a new world map of land use systems, which they claim could accurately assess the global environmental impacts of the way we use land and help provide appropriate countermeasures to minimise harm.

Land use changes come in various forms: maize fields can replace meadows and grasslands, tropical forests are cleared for pastures, steppes become cropland. The reasons are complex, the impacts are immense; animal and plant communities change, ecosystem functions disappear, carbon emissions contribute to climate change. Whatever happens regionally has global consequences.

The group, led by researchers from the Helmholtz Centre for Environmental Research (UFZ) working with colleagues at other German institutes, based their map on a number of factors, using indicators of land-use intensity, climate, environmental and socio-economic conditions. They identified twelve global patterns called land system archetypes. These include barren lands, pastoral systems and extensive and intensive cropping systems.

Most of Western Europe represents the 'intensive cropping system' that covers about 5 percent of the terrestrial Earth surface (also including Western Australia and Eastern United States). This system is characterised by high density of cropland, high inputs of nitrogen fertilisers, a temperate climate, high crop yields, large capital investments in the agricultural sector, low proportion of GDP originating from agriculture and good access to market places.

The UFZ researchers claim theirs is the most complete assessment of changes and land use compiled so far – in creating their map and developing their twelve archetypes, they analysed much more data than previous assessments used to create more traditional models of land use.

As a result, according to lead author Tomáš Václavík, "We didn't know before which regions had an unfulfilled potential for agricultural intensification given the environmental and socio-economic conditions, or in which regions the maximum agricultural yields were already achieved." He continued, "If we had analysed only the environmental indicators, we could not identify where viable opportunities for yield improvements exist."

This new analysis slightly alters the picture of land use that had been built up by scientists. For example, areas of China are now covered by five different archetypes. Václavík explained, "It was surprising to see that the intensity and type of land use in some regions of China was quite similar to the situation in Western Europe or the United States. Thus, parts of China, together with particular regions of India and, of course, large areas of Europe, were assigned to the 'intensive cropping systems' archetype."

Professor Ralf Seppelt, a landscape ecologist and co-author of the paper, said the new analysis will help the researchers form science-based policy recommendations to enable decision-makers in certain regions to avoid unsustainable land-use changes.

He said this would be particularly useful in Latin America and Southeast Asia, where many areas are classified as 'degraded forest/cropland systems in the tropics' and are characterised by extremely high soil erosion. Because the socio-economic data show that agriculture plays an important role in the national economy of the local countries, it is essential to develop and apply erosion control measures for these regions. Only then the agricultural yields could increase without negatively affecting the environment, Seppelt added.

In other land systems the situation is quite different. The extensive cropping systems of Eastern Europe or India still have a high potential to increase the agricultural yields. Such opportunities, however, are largely exhausted in the intensive cropping systems of Western Europe and the USA.

Seppelt said that the research, conducted under the GLUES project (Global Assessment of Land Use Dynamics, Greenhouse Gas Emissions and Ecosystem Services), is an important achievement in that it "[helps] us understand the interactions between human activities on the one hand and social and environmental changes on the other."