Scientists have conducted the first worldwide study of biodiversity and its impact on the productivity of forests. Data from more than 770,000 observation points from 44 countries were evaluated for this purpose. The samples included in the study comprised 8,700 species of trees from mangroves to trees in tropical rainforests, Central Europe, tundras, and dry savannas to populations in Mediterranean forests. The authors conclude that a decline in the number of species leads to massive cuts in the productivity of forests, whereas monocultures converted into mixed stands can yield significantly higher levels of timber growth.
The highest levels of biodiversity in the world are found in forests, but deforestation, forest degradation, and climate change are having a serious impact on half of all tree species. Although the preservation of the tree stock and sustainable forest management have been the subject of much discussion and have been promoted through environmental measures across the globe, the general decline in species, along with its serious consequences, continues.
The study published in the current issue of “Science” illustrates how the global decline in biodiversity is accompanied by a decline in timber growth.
“On the one hand, the study sets new standards because of its geostatistical methodology and global scope. It included an immense volume of data on biodiversity and productivity from nearly 50 countries throughout the world, which has never been done before in this field of science," said co-author Professor Hans Pretzsch, the Director of the Chair of Forest Growth and Yield Science at the Technical University of Munich (TUM).
On the other hand, the research results also lend further weight to the Brundtland Report and the Helsinki and Montreal resolutions. "The conclusion of our study is that, for example, when the number of species declines by 10 percent the wood production decreases on average by six to seven percent. And the rate of decline increases exponentially with further reduction of species richness” said Pretzsch. His team contributed a comprehensive data set of inventories and long-term experimental plots of pure and mixed stands in Central Europe.
Experimental Data over a Period of More than 150 Years
“The inventories and experimental plot data from more than 150 years demonstrate how timber growth decreases in parallel with the number of species,” Professor Pretzsch explained, “and how it can increase toward mixed stands again with the conversion of forest monocultures.” Particularly in the 1950s and 60s, Germany heavily relied on forest monocultures with only one species, such as spruce or pine, “a policy that we have consciously backed away from in the recent years. Meanwhile, the silviculture guidelines of many countries stipulate that, whenever possible, stocks should be comprised of two or three species.”
The study published in Science, which took into account the major global forest ecosystems, clearly shows that in addition to the many ecological and social benefits, mixed stands can also provide a material benefit in terms of increased productivity.
Annual Loss Estimated at around 490 Billion US Dollars
The authors have hypothetically calculated what would happen if the species continued to decline throughout the world as they have in recent years: If mixed forests continue to be cleared and converted into monocultures such as eucalyptus or pine, then productivity will steadily decrease.
With a species impoverishment of 99 percent, the approximate loss in value would be of 166 to 490 billion US dollars per year. The authors of the study note that these high losses amount to the double times the annual global expenditure for the conservation of biodiversity. Other losses caused by the reduction in biodiversity include decreases in genetic diversity, protective functions, and recovery functions, which go far beyond the reduction in timber production.
The results of the study provide the Intergovernmental Platform on Biodiversity and Ecosystem Services (UN IPBES) and the United Nations Convention on Biological Diversity (UNCBD) with an important quantitative basis for the intelligent protection and sustainable management of forests.
Liang, J., Crowther, TW., Picard, N., Wiser, S., Zhou, M., Alberti, G., Schulze, E.-D., McGuire, A.D., Bozzato, F., Pretzsch, H., de-Miguel, S., Paquette, A., Hérault, B., Scherer-Lorenzen, M., Barrett, C.B., Glick, H.B., Hengeveld, G.M., Nabuurs, G.J., Pfautsch, S., Viana, H., Vibrans, A.C., Ammer, C., Schall, P., Verbyla, D., Tchebakova, N., Fischer, M., Watson, J.V., Chen, H.Y.H., Lei, X., Schelhaas, M.-J., Lu, H., Gianelle, D., Parfenova, EI., Salas, C., Lee, E., Lee, B., Kim, HS, Bruelheide, H, Coomes, DA, Piotto, D, Sunderland, T, Schmid, B, Gourlet-Fleury, S, Sonké, B, Tavani, R., Zhu, J., Brandl, S., Vayreda, J., Kitahara, F., Searle, E.B., Neldner, V.J., Ngugi, M.R., Baraloto, B., Frizzera, L., Bałazy, R., Oleksyn, J., Zawiła-Niedźwiecki, T, Bouriaud, O, Bussotti, F, Finér, L, Jaroszewicz, B, Jucker, T, Valladares, V, Jagodzinski, A.M., Peri, P.L., Gonmadje, C., Marthy, W., O'Brien, T., Martin, E.H., Marshall, AR, Rovero, F, Bitariho, R, Niklaus, PA, Alvarez-Loayza, P, Chamuya, N, Valencia, R, Mortier, F, Wortel, V., Engone-Obiang, N.L., Ferreira, L.V., Odeke, D.E., Vasquez, R.M., Lewis, S.L. and Reich, P.B.: Positive Biodiversity–Productivity Relationship Predominant in Global Forests, Science 2016. DOI: 10.1126/science.aaf8957
Photos in High-Resolution: https://mediatum.ub.tum.de/1328858?id=1328858
Prof. Dr. Dr. h.c. Hans Pretzsch
Technical University of Munich
Chair of Forest Growth and Yield Science
Hans-Carl-von-Carlowitz Platz 2
Tel: +49 (8161) 71-4710
Forest Scholars Worldwide Team Up For Biodiversity Research
The research, published on October 14th, 2016 in the journal Science, marks the first major accomplishment of the team, formally known as the Global Forest Biodiversity Initiative (GFBI). Established in 2016, GFBI is an international, interdisciplinary, and multi-stakeholder research collaborative that aims at better understanding broad-scale patterns and processes associated with the planet's four billion hectares of forested ecosystems. For details, visit http://www.GFBinitiative.org/.
Dr. Ulrich Marsch | Technische Universität München
Kakao in Monokultur verträgt Trockenheit besser als Kakao in Mischsystemen
18.09.2017 | Georg-August-Universität Göttingen
Ultrasound sensors make forage harvesters more reliable
28.08.2017 | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy