Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

When trees aren't 'green'

11.06.2015

Poor management led to overcrowded, older trees with little understory

Most of us don't consider forests a source of pollution. As natural bodies, they should be good for the environment. But a recent study in Japan shows that older cedar and cypress plantations are causing as much pollution as a poorly managed agricultural field or urban setting.


Testing equipment was used to measure nitrogen runoff.

Photo provided by Masaaki Chiwa

Masaaki Chiwa is the lead author of the study and an assistant professor at Kyushu University in Japan. According to Chiwa, the pollution is not the fault of the trees. It's the management of the plantations. In Japan, as in other countries, natural forests usually play a significant role in maintaining water quality.

"Many Japanese cedar and Japanese cypress plantations were established in the 1950s and 1960s--60% of those on private land," according to Chiwa. "These are not natural forests; they were meant for commercial purposes."

At the time of their planting, there was a short supply of these trees. However, an increase in imports of other woods has affected prices of Japanese cedar and cypress and led to the decline in active plantation management. The result was overcrowded land with aging trees and little to no undergrowth.

These older plantations are now a source of non-point nitrogen pollution according to the study. "Point" pollution comes from a single location; "non-point" pollution comes from a more diffuse area, such as these plantations. The nitrogen is flowing from the plantations during rainfalls or snowmelts into nearby bodies of water, causing algae blooms.

Where does all this nitrogen come from? Just like in a natural forest, needles fall from the aging trees and accumulate on the plantation floor. This is part of Mother Nature's way of recycling nutrients. Earthworms and soil microbes decompose the needles and return the nutrients to the soil. Younger growth nearby finishes the process and takes up the nutrients.

However, the age of the trees in these plantations means they are growing more slowly. They use fewer nutrients from the soil than younger trees, including nitrogen. Furthermore, crowding of the trees means there is too much shade to encourage new growth. This prevents a new, healthy understory that would use the nitrogen (and other nutrients) from the soil. Because the plants are not using the nutrients, the nutrients form runoff heading to the streams.

Since cedar and cypress plantations account for 30% of the forestland in Japan, the findings of this study are significant. Chiwa and his team would recommend that the plantation land be thinned and returned to a more natural forest state.

As part of another project, some landowners thinned plantations in 2012. To verify that the thinning will reduce runoff, Chiwa and his team are now measuring the amount of nitrogen flowing from the plantations. "We have been measuring water quality to evaluate the effect of forest thinning on water quality including nitrogen loss."

Hopefully, better management will bring these plantations back to a less-crowded, more natural state, and restore their ability to clean water rather than pollute it.

The study was published in the Journal of Environmental Quality.

Susan Fisk | EurekAlert!

More articles from Agricultural and Forestry Science:

nachricht Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University

nachricht New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien

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: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

A big nano boost for solar cells

18.01.2017 | Power and Electrical Engineering

Glass's off-kilter harmonies

18.01.2017 | Materials Sciences

Toward a 'smart' patch that automatically delivers insulin when needed

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>