Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tree Species Composition Influences Nitrogen Loss From Forests

18.03.2009
The Catskill Mountains receive some of the highest nitrogen deposition rates in North America due to pollutants drifting, and a recent study in this region demonstrates how some forested watersheds are more capable than others in absorbing nitrogen. While nitrogen is an important nutrient for plant growth, excess levels are capable of acidifying soils and decreasing water quality.

Throughout the world, nitrogen compounds are released to the atmosphere from agricultural activities and combustion of fossil fuels. These pollutants are deposited to ecosystems as precipitation, gases, and particles, sometimes many hundreds of miles downwind of their release point.

The Catskill Mountains of southeastern New York are a case in point—though they contain little in the way of industrial or agricultural pollution sources, they receive some of the highest nitrogen deposition rates in North America due to pollutants drifting in from midwestern power plants and east-coast cities.

Anyone who grows plants for food, fiber, or flowers, knows that nitrogen is crucial for healthy plant growth. But excess nitrogen that leaches from a forest can acidify the soils and streams and decrease water quality. Prior research has shown that in addition to plant uptake, microbial processes are very important in retaining nitrogen in forest soils, and that forested watersheds in the Catskills vary markedly in the amount of nitrogen they can absorb and prevent from leaching away.

So why would atmospheric nitrogen deposition lead to increased losses of nitrogen from some forests and not from others? A study funded by the National Science Foundation and the U.S. Department of Agriculture provides some answers. The research, which is focused on the tree species control on nitrogen cycling dynamics in the Catskill Mountains, is published in the March-April 2009 issue of the Soil Science Society of America Journal.

Part of a long-term research project on nitrogen cycling in Catskill forests, this study utilized a stable isotope technique to determine how the microbes consume and transform nitrogen in the soil under stands of five different tree species that are common in the Catskills. Half of the forest plots also had experimental nitrogen fertilizer treatments. The study showed that forests dominated by sugar maple are particularly susceptible to nitrogen leaching, while soils under red oak and hemlock forests are better at retaining nitrogen and preventing leaching losses.

This difference was partially related to the ratio of carbon to nitrogen in the soils. The microbes under the different tree species vary considerably in their production of nitrate, the form of nitrogen that is most readily leached into streams. However, unlike previous studies from western forests, this study found very little consumption of nitrate by the soil microbes in any of the forest types. Because of the low nitrate consumption, the forest types that have high nitrate production (such as sugar maple) also have high nitrate losses via leaching.

Lead author Lynn Christenson of Vassar College in Poughkeepsie, NY noted, “The most significant difference we see in nitrogen cycling under sugar maple trees compared to other tree species are much higher rates of nitrification, with very little consumption of this nitrate occurring in sugar maple soils. Why the soils and trees are not consuming this nitrogen is still a mystery.”

Project Leader Gary Lovett of the Cary Institute of Ecosystem Studies in Millbrook, NY stated, “It is important for watershed managers to know that differences in tree species composition can influence nitrogen retention. Some forest types are more likely to saturate with nitrogen than others.”

Soil Science Society of America Journal, http://soil.scijournals.org, is a peer-reviewed international journal published six times a year by the Soil Science Society of America. Its contents focus on research relating to physics; chemistry; biology and biochemistry; fertility and plant nutrition; genesis, morphology, and classification; water management and conservation; forest, range, and wildland soils; nutrient management and soil and plant analysis; mineralogy; and wetland soils.

The Soil Science Society of America (SSSA) is a progressive, international scientific society that fosters the transfer of knowledge and practices to sustain global soils. Based in Madison, WI, and founded in 1936, SSSA is the professional home for 6,000+ members dedicated to advancing the field of soil science. It provides information about soils in relation to crop production, environmental quality, ecosystem sustainability, bioremediation, waste management, recycling, and wise land use.

SSSA supports its members by providing quality research-based publications, educational programs, certifications, and science policy initiatives via a Washington, DC, office.

SSSA is the founding sponsor of an approximately 5,000-square foot exhibition, Dig It! The Secrets of Soil, which opened on July 19, 2008 at the Smithsonian's Natural History Museum in Washington, DC.

Sara Uttech | Newswise Science News
Further information:
http://www.soils.org

More articles from Agricultural and Forestry Science:

nachricht Trees and climate change: Faster growth, lighter wood
14.08.2018 | Technische Universität München

nachricht Animals and fungi enhance the performance of forests
01.08.2018 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

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: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

Unraveling the nature of 'whistlers' from space in the lab

15.08.2018 | Physics and Astronomy

Diving robots find Antarctic winter seas exhale surprising amounts of carbon dioxide

15.08.2018 | Earth Sciences

Early opaque universe linked to galaxy scarcity

15.08.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>