Reflections on Water - Chapter 4, Buffering our World with Water
Chris Nicodemus & Katrina Meserve
Reflections on Water is a series of discussions exploring the role of water as a community resource and how society’s treatment of this resource can have far reaching consequences for us all. In 2024 the Reflections series focused on geography, geology, and weather and the interaction of water with these defining components of our living space. We have noted that water is and will continue to be plentiful in Northern New England since large quantities of surface water can be found adjacent to this geography in all directions. We also have explored how our terrain serves to collect and store our water and thus provides for its future access and how if we disturb it without careful planning, we can inadvertently harm the quality of the community’s water by releasing sequestered toxins that it may carry.
The natural world reacts to any local environment favoring the organisms that thrive in the conditions imposed. Bountiful varieties of life can be found in water rich, temperate climates such as our own. Curiously, nature itself also serves to buffer the environment from extremes and allows the environment we both know and love to thrive. Water is central to many of the environmental buffer systems that maintain the natural balances needed by our eco-systems to flourish. The physical properties of water provide direct buffering of air temperature. The energy required to transition water from solid to liquid and from liquid to gas and the point these phase changes occur define the temperature buffer. This translates to whether one experiences frost in the early hours of a clear morning or to how high the temperature actually will rises on a sunny early summer afternoon. Water also serves as the medium for the chemical balance between the surface and subsoils. In this case, the chemical buffering is caused by the balance of acids in the water and the associated salts of those acids. These chemical buffer systems provide for relative neutrality of the water used by plants to grow and the characteristics of a bog or grassland or forest will be heavily influenced by this balance. We feel it is also reasonable to credit water for the physical buffering to the landscape that the growth of plants and forests provide to the extreme forces of nature. A forest serves to buffer its understory from extremes of temperature and wind. For those of us who are avid skiers of glades, we know well the quiet wonder of a magical snow world sheltered from the high mountain chilly winds. We have been warmed from the exertion of navigating these tight canopy protected spaces, while less experienced skiers sip hot chocolate in the lodge and complain about the extreme cold they were experiencing out on the open slopes. For those living near a highway, a buffer planting can quiet the noise of traffic and hide the traffic from view.
On a hot summer day, a forest canopy will absorb the energy of the sun and divert that “heat” into new growth incorporating carbon dioxide and water into sequestered more complex carbon rich molecules forming leaves and wood. The temperature under the canopy will be buffered and comfortable in stark contrast to an open space with little vegetation. Natural vegetation also serves as a sponge to collect and store excess water. Preserving shrubs and trees along the shores of our waterways provides a critical buffer against the extremes of flooding in the event of an extreme rain event or a failed dam. Water will rise above the usual shoreline barrier if the volume of flow exceeds the available space between the riverbanks. However, if the excess water spills into a complex forested terrain, the water will spill into pockets and the force of the water will be absorbed and dissipated by the vegetation. Ironically the berms and dikes used to protect property from flood paradoxically cause the energy of a flooding stream to concentrate causing flood levels to rise and cause increased damage downstream.
If the slopes adjacent to a mountain stream are forested, moisture retained under the canopy will provide for a steady trickle of ground water into adjacent streams and the stream will maintain flow year-round, supporting a rich variety of life. However, if much of the wooded slope is deforested the moisture is not retained, the ground will be baked by direct sunlight and a previously perennial streams in the watershed may go intermittently dry, drastically altering the ecosystems it can maintain. Furthermore, snowmelt and heavy rain on the deforested slopes will collect rapidly in the stream beds with extremes of flow and downstream flooding along with erosion and loss of surface soils that are carried as sediment and deposited downstream.
New England was deforested by European settlers and many of the protective features of water nurtured natural buffers were lost. Local extremes of heat and cold, floods, landslides, erosion and diminished flora and fauna were experienced and are well described in our local historical record. Our local climate and conditions, however, were not irreparably changed by these disturbances and the available waters provided for a rapid recovery and reforestation of the region. That outcome may not have been assured and in other locations deforestation can be irreversible or only very slowly reversed. There are excellent examples of this in arid Mediterranean geographies and we also commend our readers to Ben Goldfarb’s interesting book Eager, The Secret Life of Beavers and Why They Matter (Chelsea Green Publishing 2018) that considers how the near elimination of beavers from the American west in the 19th Century has adversely impacted waterways, water reserves, aquifers, local climate and the ecology of the American West in a way that has not yet been able to recover.
Water is a climate buffer, and its by-products provide for a sustainable environment in many ways. We will further explore a few examples in the Discussion follow up in March as we witness the buffer of melting ice holding our temperatures in moderation with the onset of Spring.
Banner Photo by: EP Chow
