Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The intensity of land use doubled in the 20th century

04.06.2013
The growth of green plants – which can be measured in terms of “net primary production”, or NPP for short – provides the energetic foundation for all life on earth.

The share of NPP appropriated by humans (HANPP) through agriculture and forestry, bioenergy production, and vegetation fires doubled over the course of the past century. Researchers at the Institute of Social Ecology at the AAU have shown that while land is used more efficiently, simultaneously, the intensity of land use has increased continuously.

In a study published in PNAS Proceedings of the National Academy of Sciences), researchers warn that an increased expansion of bioenergy use would drastically raise HANPP to over 40%.

The growing global population and its increasing hunger for resources gives cause for concern for various reasons, in particular with regard to the sustainability of the current and future use of natural resources. The so-called HANPP indicator is a measurement for the intensity with which humans use land and biomass. HANPP stands for “Human Appropriation of Net Primary Production” and provides information about the impact of human activity upon the biosphere.

HANPP reveals the percentage of the annual plant-based biomass production that is co-opted by humans through land use activities such as agriculture and forestry, bioenergy production, construction of buildings and infrastructures, soil degradation, or human induced vegetation fires – and thus not available to other ecosystem processes.

A study recently published in PNAS quantifies for the first time long term trends in HANPP during global industrialization covering the period from 1910 to 2005. The authors, including Fridolin Krausmann, Karl-Heinz Erb, Simone Gingrich, Helmut Haberl, Veronika Gaube, Christian Lauk and Christoph Plutzar from the Institute of Social Ecology, and Tim Searchinger from Princeton University arrived at a surprising result: While global population increased fourfold over the past century, and economic output increased 17-fold, HANPP “only” doubled. “This shows us that land use became more and more efficient across the globe: The production of food and other products has increased at a much faster rate than HANPP. Nevertheless, HANPP has climbed from 13 to 25 per cent during the past century”, Fridolin Krausmann, lead author of the article, explains.

While global consumption has increased dramatically, the amount of biomass harvested and used per capita has dropped significantly. Krausmann elaborates: “One of the reasons for this is that – seen from a global perspective – bioenergy has increasingly been replaced by fossil energy. Furthermore, efficiency of conversion processes from biomass to products such as food or fibre has grown.” However, as the authors of the study point out, there are major drawbacks: The impressive increase in efficiency gains in crop and livestock yields have been achieved at considerable ecological costs. “In order to increase yields and output, we use large amounts of fossil fuels and water, we turned to large-scale industrial animal production systems and put high environmental pressure on land, soils and biodiversity”, Krausmann points out.

The authors assume that, given a continuation of the past trends, global average HANPP is likely to increase moderately to values up to 29 per cent by 2050. However, if bioenergy is to be expanded by as much as some IPCC scenarios suggest, the value could climb as high as 44 per cent, clearly exceeding the growth rate observed over the past decades and putting high pressure on ecosystems. The researchers thus call for caution: “Caveats are warranted concerning bioenergy strategies. The utilization of vast land areas for the production of bioenergy can have a strong negative impact on food safety, forest resources, and biodiversity. Unrealistic expectations regarding bioenergy can result in failing to achieve the target of reducing greenhouse gases. Above all, we have to focus on sustainable intensification and we have to be careful to prevent any potential negative consequences of forms land use intensification that further increase the pressure on ecosystems.”

Fridolin Krausmann, Karl-Heinz Erb, Simone Gingrich, Helmut Haberl, Alberte Bondeau, Veronika Gaube, Christian Lauk, Christoph Plutzar & Timothy D. Searchinger (2013). Global human appropriation of net primary production doubled in the 20th century. PNAS, Early Edition (EE), week of June 3, 2013.

Dr. Romy Müller | idw
Further information:
http://www.iff.ac.at/socec/
http://www.aau.at

More articles from Agricultural and Forestry Science:

nachricht Climate change, population growth may lead to open ocean aquaculture
05.10.2017 | Oregon State University

nachricht New machine evaluates soybean at harvest for quality
04.10.2017 | University of Illinois College of Agricultural, Consumer and Environmental Sciences

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>