Riparian Areas
Table of Contents
Introduction
A riparian area is the lush band of vegetation in the floodplain of a river. Riparian areas occur on both year-round rivers and seasonal creeks. They are one of the most important ecosystems in many regions.
Welcome to the Riparian Zone
This 2:05 minute video explains the benefits of maintaining and restoring riparian areas for fish conservation.
These underappreciated eco-systems are major workhorses which are under constant threat from humans, especially on farms or due to development. They offer many benefits, so restoring and protecting them are critical for the following reasons.
Bank Stabilization
Riparian borders help stabilize the banks of waterways with their roots helping to hold soil in place, even during major flooding or rain events. Their foliage can also help reduce the impact of erosion, even capturing some of what is washed downstream, and helping to build up certain areas.
Biodiversity Boosting
These are vital habitats which can support as much as 80% in desert eco-systems, even though they make up a relatively small fraction of space in a given region.
Many species nest near waterways, sometimes directly in the bank or in nearby trees. They can function as critical habitat for species like fish, especially when large pieces of wood fall into water, creating nesting and hiding locations for them.
Riparian ecosystems can also function as wildlife corridors, especially through spaces that have been converted for human development. Similarly they can act as resting spots for migratory species.
Clean Water
Riparian buffers help keep pollutants and excess sediment out of waterways, meaning cleaner water for people and animals who use that water. Reduced pollution helps organisms, who in turn help clean water down stream, such as shellfish, and seagrasses.
"One analysis of multiple studies ... found that buffers in general removed 67% of nitrogen, and wider buffers of at least 50 meters can remove 85%!" - SciShow
Stabilize Water Temperatures
The shade provided by plants, particularly trees helps maintain temperatures that support life. This means more available oxygen in the water. As the climate gets hotter, rivers that have been stripped of their trees can become so warm that fish and other species die off.
Warmer water also translates to faster evaporation, meaning rivers are more likely to run dry during droughts when their banks have been deforested.
Riparian Vegetation
Plants are the key ingredient for healthy and functional riparian zones. They stabilize the banks against all the elements including rain, keep out pollutants, boost the water cycle, reduce the energy of floods which reduces erosion, provide habitat for other wildlife, and so much more.
"Just 30 meters of plants on each side of a river can help keep the water temperature the same as if the river flowed through a massive forest." - SciShow
How Plants are Bringing Rivers Back
Riparian borders prevent erosion, protect waterways from pesticides and other types of run off. They help keep waterways cooler, which minimizes deaths caused by large temperature swings. They also provide habitat for all kinds of animals, including places to feed, reproduce, or simply to travel through in our increasingly divided landscapes.
Colonizers
These are the first species to move into bare ground, for example on freshly dumped sandbars after major flood events. They begin the stabilization process and provide shelter for the stabilizers to move in.
Stabilizers
These plants have deeper roots and
Explore our Trees page to learn about successful planning, common mistakes to avoid, and our growing list of organizations, governments, and programs offering free or cheap trees. The page also includes resources like grants for farmers or schools to put towards trees and planting/growing supplies.
Where to Restore
Farmland
Farmland uses close to half of Earth's habitable land. Over thousands of years we've cut down woody areas to make more room for crops, as well as allowed livestock to graze and trample riparian zones. Livestock and their feed make up around 77% of global farm land, making them some of the largest threats to riparian spaces.
Riparian Management: Increasing Biodiversity on Farms
1:48 minute video explains benefits of riparian areas for farmers as well as their land.
Urban Areas
Urban and built-up areas one take up around 1% of the planet's habitable space, but this is quickly expanding, and places that have long-been urbanized have high levels of pollution.
Since riparian zones help protect waterways from pollutants, it's always a good idea to put a buffer zone of plants and trees between roadways and waterways.
Sustainable Drainage Systems
SUDs use natural elements including earthworks and plants to help slow water flow, sequester water into landscape, and protect communities from intensifying weather patterns.
Greenways / Greenbelts
Greenway or greenbelts have many uses, but they can work particularly well when combined with waterways, maintaining or even expanding riparian borders as part of a community's flood prevention system and nature preservation.
Resources & Guides
Europe
Scotland
SEPA's Engineering in the Water Environment Good Practice Guide, Riparian Vegetation Management "This document is one of a series of good practice guides produced by SEPA to help people involved in the selection of sustainable engineering solutions that minimize harm to the water environment. This Guide provides guidance on the establishment and sustainable management of vegetation in the riparian zone of rivers, lochs and wetlands for the benefit of the environment and people."
North America
Canada
Alberta
Indicators for Assessing Environmental Performance of Watersheds in Southern Alberta (PDF) This gives general guidance, but doesn't focus much on specific species.
Keystone Species
Beaver are helpful engineers in North America, Europe, and Northern Asia. They help slow water, and create wetlands. Their presence may cause the destruction of a few trees, but the ecological benefits can help many more trees replace those that are lost to dam building.
Willow
There are many types of willow, with weeping willows probably being the most famous. Weeping willows are from China, but other species are native to other countries and continents. Try to make sure you are using native willows for rewilding projects.
Organizations
North America
USA
Minnesota
The Mississippi Watershed Management Organization "works to protect and improve water quality, habitat and natural resources in an urban watershed that drains directly into the Mississippi River. We are a joint-powers local government unit and one of approximately three dozen watershed organizations in the Twin Cities metropolitan area."
Oceana
Australia
Greening Australia: Reef Aid "To improve water quality on the Great Barrier Reef, we are working with landholders, communities and Traditional Owners to rebuild eroding gullies and restore vital coastal wetlands across the catchment."
Maps
North America
USA
Stormwater Management and Restoration Tracking (SMART) Tool (Interactive) Tool tracks storm water management practices in the Chesapeake Bay Watershed which spans, Delaware, New York, Pennsylvania, Virginia, and West Virginia
Grants
North America
USA
Minnesota
Stewardship Fund Grants "support public efforts to manage stormwater, control pollution, and improve water quality and habitat."