Forests and Fish
A forested watershed or even a stream with a forested buffer produces cleaner water and more consistent flows than cleared land. This means not only less flood and drought, but also quantifiable safer water for human and wildlife needs.
Without trees, there are fewer leaves and less total surface area for evapotranspiration, so there’s less moisture in the air. Without a protective canopy of leaves, the soil is struck with the full force of the storm. Individual raindrops are like little bombs, gouging, beating , and battering the soil, lifting and splashing it back and forth, churning it into pasty mud that clogs pores and passages in the soil. There is less biological activity in the soil in a field than there is in forest soil, so the earth is less tunneled and less water percolates down into the groundwater. As the groundwater recedes, the springs falter, the streamflow slows, and some streambeds will eventually run dry.
When rain falls on a forested watershed, the canopy breaks the force of the falling drops, and a resilient mat of twigs, leaves, moss, and dead and decaying plants keeps the soil from splashing. Over half the rain that falls on a forest goes directly back into the air through evaporation and transpiration, creating a moist and clouded microclimate. Some of the rain slowly percolates down through the forest soil to become the groundwater that reemerges in springs, and some of the rain runs over the surface of the soil and enters the waterways. (Water: A Natural History by Alice Outwater)
European colonizers denuded much of Virginia’s land. By 1835, half of the Chesapeake Bay watershed’s forests were cleared. The products of agriculture and forestry have been essential to life and the creation of wealth for the greater part of our Commonwealth’s existence. Virtually all forests were at some point cleared. This change in the landscape had drastic consequences for our waters and soil.
Without trees, there are fewer leaves and less total surface area for evapotranspiration, so there’s less moisture in the air. Without a protective canopy of leaves, the soil is struck with the full force of the storm. Individual raindrops are like little bombs, gouging, beating , and battering the soil, lifting and splashing it back and forth, churning it into pasty mud that clogs pores and passages in the soil. There is less biological activity in the soil in a field than there is in forest soil, so the earth is less tunneled and less water percolates down into the groundwater. As the groundwater recedes, the springs falter, the streamflow slows, and some streambeds will eventually run dry.
When rain falls on a deforested watershed, the runoff races downhill in millions of little currents, combining into torrents of water that gouge and gully the hillside…The stream becomes wider and shallower, shifting to steeper slopes and eroding the bank as it goes. The runoff sweeps along tons of topsoil, gravel, and stones, and dumps the spoils into the waterways.
(Water: A Natural History by Alice Outwater)
(Water: A Natural History by Alice Outwater)
The decline of agriculture as the dominant source of livelihood in the 1900s led to an age of reforestation in the James River watershed until burgeoning suburban growth began to counteract this trend. Today the health of the James River continues to hang in the balance, as pressure to develop sprawled, inefficient communities remains steady. Even with the market for existing homes glutted with supply, and countless opportunities for development within the existing boundaries of cities and towns, we continue to see forest and farmland cleared for subdivisions.
Beyond understanding their value in maintaining the integrity of our water supply, it is inspiring to visit the few relatively intact forests we still find in Virginia. Walking under the majestic canopy of a mature forest is a gratifying yet humbling experience. We must go and seek out these places, for they are few. One place to experience a great forests remaining in the James River watershed is near Buchanan, VA along the trails that lead to Apple Orchard Falls.* A more accessible and less strenuous option lying just outside the James River watershed is James Madison’s Montpelier home which features a remarkably intact forest.**
Find your way to a great old forest this summer and remember to thank it for keeping our water supply clean.
*The Apple Orchard Falls-Cornelius Creek loop is east of Buchanan in the Jefferson National Forest along the western side of the Blue Ridge below the Parkway. The best trailhead access is from the end of Forest Road 59 or from Sunset Field Overlook at milepost 78.7 on the Blue Ridge Parkway. To get to the FR 59 trailhead, take exit 168 off I-81 just north of Buchanan, follow Route 614 just over 3 miles through Arcadia, then turn left at the North Creek Campground sign onto FR 59. In about 4 miles, past the campground, the road will end at a trailhead. The Apple Orchard Falls Trail leads left out of here; the Cornelius Creek Trail is to the right.
**Montpelier is located in 4 miles south of Orange, VA on Rt. 20. See the Montpelier website.
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