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Groupe d'étude de marché

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Farhat Zinoviev
Farhat Zinoviev

3 : Across The River And Into The Trees

Formed by the confluence of Coharie and Six Runs Creeks, the Black River snakes its way over 60 miles through portions of Sampson, Bladen and Pender counties before emptying into the Cape Fear River 14 miles above Wilmington. Upstream the waters flow more swiftly past large forests of oaks and other bottomland hardwoods and cypress and tupelo gums in the wetter swales. Occasional high banks rise above the river, the highest being a 60-foot bluff with mountain laurel and galax. Further downstream the river slows and spreads out into expansive bald cypress-dominated swamps. In a few places, sandy upland sites along the river support longleaf pines and turkey oaks.

3 : Across the River and into the Trees

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Dr. Stahle thought there may be trees much older along the river. His suspicions were right: in the spring of 2019, Dr. Stahle announced that he had identified one cypress to at least 605 B.C.E., the time of the Babylonian empire, making bald cypress the fifth oldest tree species in the world. He has found many other ancient cypress along the river dating well over a thousand years. These are the oldest trees in North America east of the Great Basin.

The river makes for an incredible paddle trip. Keep in mind that water levels fluctuate significantly during the year. You may have to maneuver and/or portage around fallen logs and trees during dry periods.

The river makes for an incredible paddle trip. Keep in mind that water levels fluctuate significantly during the year. You may have to maneuver and/or portage around fallen logs and trees during dry periods. Following the Pender County/Bladen County line, the Black River is easy to see on a map. Some of the old-growth bald cypress can be seen from the NC 53 bridge 4 miles south of Atkinson.

Despite how the Delaware River is commonly portrayed in works of art, the site where General Washington and his army crossed was rather narrow. Durham boats and flat ferries were used to cross. They were probably fixed to a wire strung across the river.

The venerable trees were alive centuries before the advent of Christianity and the English language. David Stahle, a researcher in the department of geosciences at the University of Arkansas, cored the trunks and established the ages of the two trees. He believes even older trees may grow in the swamp and along the river.

But now the Indians were rushing out and shooting back, making show enough to check the attack. The whites dismounted. Every fourth man took the reins of three other horses and led them along with his own into the trees near the river. The other soldiers deployed in a skirmish line of perhaps 100 men. It was all happening very quickly.

By then the soldiers had begun to bend back around to face the Indians behind them. In effect the line had halted; firing was heavy and rapid, but the Indians racing their ponies were hard to hit. Ever-growing numbers of men were rushing out to meet the soldiers while women and children fled. No more than 15 or 20 minutes into the fight the Indians were gaining control of the field; the soldiers were pulling back into the trees that lined the river.

The Cauvery originates in the Kodagu hills of the Western Ghats in Karnataka state, flows east across the subcontinent, and drains into the Bay of Bengal in Tamil Nadu state. Along its 805-km (500-mi) course, the Cauvery is flanked by forests, grasslands, farms, cities and rural settlements, with several dams interrupting its natural flow. Millions of people along its course depend on its water for agriculture, industry and daily use, leading to frequent water disputes over the last few decades.

The initial plan, according to the draft policy recommendation, was to plant trees along a kilometer-wide ribbon of buffer zones either side of the Cauvery, and half a kilometer wide along its tributaries. Such an endeavor would call for planting nearly 2.5 billion trees, covering one-third of the river basin.

ATREE fellows Veena Srinivasan, Sharad Lele, Jagdish Krishnaswamy and Priyanka Jamwal spelled out the science behind their concerns in an article published in the Economic Times in 2017. In it, they said planting trees along a river is unlikely to impact local rainfall patterns.

They said that while there is evidence that large forests contribute to rainfall, changes can be expected to occur only at regional or continental scales. The same logic applies to trees being planted in the river basin.

The ATREE researchers, however, pointed out that the real reasons for the erosion along riverbanks is not due solely to the absence of trees. Instead, rampant sand mining and dams that divert water for irrigation and cities have led directly to erosion.

Flip-Flopping FlowThe Amazon River used to flow in the opposite direction. Today, the river flows from the mountains of Peru in the west to the Atlantic Ocean in the east. But millions of years ago, it actually flowed from east to west, emptying into the Pacific Ocean. The flow flipped when the Andes mountains started growing at the end of the Cretaceous period (around 65 million years ago).

By afternoon, a steady, cold deluge is expected to settle in, extending for 20 or 24 hours across the region, into Thursday afternoon or evening, said Rick Canepa, a meteorologist with the National Weather Service.

At some points in the river, lovely limestone formations emerge from the banks and bottom of the river. We also believe we saw two or three spots where clear water trickled into the Peace in a little streamlet, and it sure looked like an artesian spring to us. (I was surprised.)

More than 65 ponds and lakes border or are located within the unit, totaling approximately 3,500 acres. About 100 miles of brooks, streams and rivers drain into three major watersheds - the Raquette River, the Hudson River and the South Branch Moose River. Sections of the South Branch Moose River, Otter Brook, Red River and Cedar River are designated scenic rivers.

Very large rivers are usually low gradient and very wide, resulting in negligible influence of riparian canopy in terms of shading and leaf-litter input. Water currents keep fine solids in suspension, reducing light penetration to the benthos. Organic matter in suspension is by far the largest food base in these very large rivers.Changes in physical habitat and food base from river source to mouth profoundly influence biological communities. Aquatic ecologists classify benthic macroinvertebrates into functional feeding groups: shredders that eat leaves, collectors consuming fine particulates, grazers that scrape periphyton from substrates, and predators of animal prey (Cummins & Klug 1979). Smaller temperate streams tend to be co-dominated by shredders primarily consuming leaf litter, and collectors consuming particles (Figure 1). As canopies open in larger streams, grazers become common with increased periphyton production. With less canopy cover in wider streams, shredder abundance is reduced. Collectors utilize particles in streams of all sizes, but they dominate benthic communities in larger streams where suspended organic matter is common. Predators represent a small but important fraction of benthic communities in rivers of all sizes.The fish zonation concept (Thienemann 1925, cited by Schmutz et al. 2000) generalized Western European river habitats based upon a predictable sequence of dominant fish species (Huet 1959). Analogous fish community responses to river slope and size have been found in African, South American, and many North American streams (McGarvey & Hughes 2008). Larger rivers can accommodate larger fish as well as small fish, and so the size range of fish increases as rivers become deeper. River discharge is the volume of water passing a particular location per unit time. The species-discharge relationship is analogous to the species-area relationship, and describes how fish diversity increases with river size (Figure 2; McGarvey & Milton 2008).

In low to moderate-gradient streams with loose rocky substrates, cobbles and boulders are mobilized during high-flow events and deposited across the width of river channels forming high-gradient riffles (Figure 4). Riffles are separated by pools, forming riffle-pool sequences recurring about three to five times the width of the river (Hynes 1970; Montgomery and Buffington 1997). During typical base-flow conditions, riffles are erosional habitats with fewer deposited fine particles between substrates. Particulate deposition increases as water velocity slows in pools. Riffle macroinvertebrate communities are typically more diverse than communities in pools. The pattern in fish communities is reversed, with pool fish communities tending to be more diverse than those in riffles (Figure 5; Gelwick 1990, Langeani et al. 2005).

But in the summer, when it doesn't rain in Los Angeles, the river doesn't just run dry. Instead, it's fed by wastewater discharged from three wastewater treatment plants in L.A., Burbank and Glendale. This water is typically cleaner than water that flows into the river from city streets and storm drains (more on this later).

The flood marked the end of the river being a river. Afterwards, the dam-building, river-righting men at the US Army Corps of Engineers began encasing the river in a deep concrete channel that would keep it from spilling out of its banks during future floods. They erected fences and put up "No Trespassing signs." It took 20 years and 3.5 million barrels of cement, according to "The Los Angeles River, Its Life, Death and Possible Rebirth," but by the end the the river had been erased, transformed from an ecosystem into a freeway for moving flood water efficiently and safely from mountains to the sea.

That said, the Los Angeles regional branch of the State Water Resources Control board ultimately has the responsibility for bringing the river into compliance with the federal Clean Water Act's water quality standards. But sadly, "we are not close. We are still pretty far away (from meeting the standards), and we don't have the resources that we would like," said Heather Repenning, the vice president of the city of LA's Board of Public Works. 041b061a72

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