Factors affecting shore ecozones: Inputs of physical energy, geologic structure, the hydrologic regime, biota and climate

Freshwater shore zones are among the most ecologically valuable parts of the planet but have been heavily damaged by human activities. 

Management and rehabilitation of freshwater shore zones could be improved by better use of ecological knowledge and ecological functioning according to scientists at New York's Cary Institute of Ecosystem Studies in Millbrook NY.

http://www.caryinstitute.org  -- "Ecology of Freshwater Zones" by David Strayer and Stuart Findlay: http://link.springer.com/article/10.1007/s00027-010-0128-9 

Shore zones are complexes of habitats that support high biodiversity which are enhanced by high physical complexity and connectivity. Shore zones dissipate large amounts of physical energy, can receive and process extraordinarily high inputs of autochthonous and allochthonous organic matter, and are sites of intensive nutrient cycling. Interactions between organic matter inputs (including wood), physical energy, and the biota are especially important. In general, the ecological character of shore zone ecosystems is set by inputs of physical energy, geologic (or anthropogenic) structure, the hydrologic regime, nutrient inputs, the biota, and climate. 

Humans have affected freshwater shore zones by laterally compressing and stabilizing the shore zone, changing hydrologic regimes, shortening and simplifying shorelines, hardening shorelines, tidying shore zones, increasing inputs of physical energy that impinge on shore zones, pollution, recreational activities, resource extraction, introducing alien species, changing climate, and intensive development in the shore zone. 

Systems to guide management and restoration by quantifying ecological services provided by shore zones and balancing multiple (and sometimes conflicting) values are relatively recent and imperfect. 

Working with nature and not against it: Sandbars

Sandbars are a critical component of the Grand Canyon ecosystem, providing essential habitat, like warm backwaters, for species in the river’s intricate food web. The creation and maintenance of sandbars, however, depend on how much sediment is coming into the system and how fast the water carrying that sediment is flowing.

Prior to construction of Glen Canyon Dam, the Colorado River transported some 60 million tons of sand each year, and flows varied by as much as 600 percent from one year to the next. Each spring, an inundation of meltwater often left new sandbars and beaches in its wake.

Today, the dam has cut off 94 percent of the river’s sand supply and tamed its wildly fluctuating flows, eliminating large spring floods altogether. However, in order to provide water and electricity, the average daily flow is now often higher than before the dam was constructed. 
  
Earth Magazine reports:  http://www.earthmagazine.org/article/releasing-flood-controversy-colorado-river 

Scientists have seen habitat changes reverberating through the Grand Canyon’s food chain. Organic matter from throughout the river’s basin once sustained a diverse group of aquatic insects and formed the base of a complex food web.