White-tailed deer and the science of yellow snow
June 4, 2013 New research from wildlife ecologists at Michigan Technological University indicates that white-tailed deer may be making the soil in their preferred winter homes unfit to grow the very trees that protect them there.
Bryan Murray, a PhD candidate at Michigan Tech, and two faculty members, Professor Christopher Webster and Assistant Professor Joseph Bump, studied the effects on soil of the nitrogen-rich waste that white-tailed deer leave among stands of eastern hemlock, which are among their favorite wintering grounds in the harsh, snowy climate of northern Michigan. Webster and Bump are on the faculty of Michigan Tech's School of Forest Resources and Environmental Science.
They compared eastern hemlock stands where deer congregated to stands where deer were fenced out and found a strong relationship between the amount of soil nitrogen from the deer's waste products and the kinds of plants that flourished there. Their research results were reported online in the journal Ecology, published by the Ecological Society of America.
"Altering the nitrogen availability in a hemlock stand may affect its ability to continue functioning as a deeryard by changing the types of plants that grow there," said Murray, first author on the journal article titled "Broadening the ecological context of ungulate-ecosystem interactions: the importance of space, seasonality, and nitrogen." For example, he said, "high inputs of nitrogen may hasten the transition of hemlock stands to hardwood species that provide scant winter cover."
During cold northern winters, deer seek out stands of evergreens with dense crowns, such as eastern hemlock, northern white cedar and balsam fir. Such stands of trees are known as "deeryards." They are thought to provide refuge from deep snow and blustery winds and to help deer hide from predators, Murray explained.
Deer instinctively seek deeryards, but their choice of location is knowledge passed from mother to fawn. Thus deeryards that are traditional favorites can harbor 100 deer or more per square mile, creating hotspots of high-nitrogen-content waste.
Long ago, before logging enabled the white-tailed deer to move further and further north and before the deer population explosion more recently experienced, the ecosystem stayed balanced because there were plenty of deeryards and fewer deer. Now more deer are crowding into less winter cover, shifting the dynamic balance of nature.
The Michigan Tech research demonstrates that the relationship of deer to their habitat is more complex than just the plants they eat, Webster said. "Our hope is that by better understanding the links between habitat use and spatial patterning of resources and plants in survivng hemlock stands we can identify sustainable management strategies for this critical resource."
"It was fascinating to discover such complex interactions, which have implications for sustainable management, in a seemingly simple ecosystem," Murray added.
Welcome to SUV System Ltd!
SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.
We have built up long term business relationship with about many companies which are stockers and authorized agents. we have a steady and reliable supply to meet customer's demands to the greatest extent .Confidently, we are able to lower your cost and support your business with our years of professional service.
SUV System Ltd is Electronic Components Distributor Supplies,Find Quality Electronic Components Supplies Products IC(Integrated Circuits),Connectors,Capacitor,Resistors,Diodes,Transistors,LED at Suvsystem.com. Sourcing Other Energy, Environment, Excess Inventory Products from Manufacturers and Suppliers at Suvsystem.com
Electronic Components distributor:http://www.suvsystem.com
Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html
IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html
LED Distributor:http://www.suvsystem.com/l/LED-1.html
Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html
Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html
Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html
Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html
SUV System Ltd insists on the managing faith ofsincereness,speciality,foresight, win-win,so we build up stable-relationship customers located all over the world, including the States, Europe, Argentina, UAE, Malaysia, Australia,and India etc
we are focus on the following fields,and hope we can help you.
CR0805-FX-1911E CR0805-FX-1910ELF CR0805-FX-1910E CR0805-FX-18R2ELF CR0805-FX-18R2E CR0805-FX-18R0ELF CR0805-FX-18R0E CR0805-FX-1873ELF CR0805-FX-1873E CR0805-FX-1872ELF CR0805-FX-1872E CR0805-FX-1871ELF CR0805-FX-1871E CR0805-FX-1870ELF CR0805-FX-1870E CR0805-FX-1823ELF CR0805-FX-1823E CR0805-FX-1822ELF CR0805-FX-1822E CR0805-FX-1821ELF CR0805-FX-1821E CR0805-FX-1820ELF CR0805-FX-1820E CR0805-FX-1804ELF CR0805-FX-1804E CR0805-FX-1803ELF CR0805-FX-1803E CR0805-FX-1802ELF CR0805-FX-1802E CR0805-FX-1801GLF CR0805-FX-1801G CR0805-FX-1801ELF CR0805-FX-1801E CR0805-FX-1800GLF CR0805-FX-2204E CR0805-FX-2203ELF CR0805-FX-2203E CR0805-FX-2202ELF CR0805-FX-2201ELF CR0805-FX-2201E
http://www.suvsystem.com/a/2397.aspx
没有评论:
发表评论