Monthly Archives: April 2018

Biodiversity = Sustainability

Ask ecologists what is the best measure of the health of an environment and they will tell you diversity. There are a multitude of ecological niches from the frozen tundra to boiling hot springs, from bone dry deserts to ocean expanses. In every case, greater biodiversity signals greater productivity and hence greater sustainability. Broader plant diversity means more food available to herbivores, and more herbivores makes for more prey animals.

Homo Sapiens, the only species on the planet that is actually capable of thinking about its impact, doesn’t. At least not much. We might forgive our Ice Age ancestors for wiping out most the megafauna on the planet because they didn’t realize their impact, but whenever humans showed up on the scene large animals disappeared. Other than Africa where we co-evolved with several large mammals, few are left around the world. Even the African species are dwindling.

The slaughter began as modern humans migrated out of Africa as early as 100,000 years ago. Europe, Asia, Australia and finally the Americas saw the rapid disappearance of large mammals. Some blame may be placed on changing climate, especially what is called the Holocene extinction at the end of the last glacial period, about 12,000 years ago. This period coincided with human migration into the Americas. Not only did the more northerly megafauna disappear but others such as a giant beaver as big as a compact car and a giant ground sloth which towered over 20 feet tall.

A similar rapid extinction took place when humans made their way to Australia about 40,000 years ago. A prehistoric marsupial weighing in at 3 tons disappeared shortly after human arrival. Also on the extinct list are a 2 ton Goanna (lizard), a turtle with a shell diameter of over 6 feet, and 500-pound flightless bird.

Probably the best-known example of a human-caused extinction is that of the Dodo, a 50 pound flightless relative of pigeons. Over a very short period of time it was extirpated from its island in the Indian Ocean. The Dodo was first seen by Dutch Sailors in 1598. It was gone from history by 1662, a species driven to extinction over the course of one human lifetime.

At the same time that we drive wild megafauna to extinction, we are replacing them with a very limited number of livestock, principally cattle, sheep, hogs and chickens and little else.

The combined mass of humanity is currently around 300 million tons, that of our livestock, 700 million tons. Compare that with the combined weight of everything from beavers to blue whales, which adds up to only 100 million tons. There are 200,000 wolves in the wild compared to 400 million dogs. Our closest relative the chimpanzee number about a quarter million compared to 7.6 billion of us.

The last western Black Rhino died in 2011, the last male Northern White Rhino died last month, leaving two infertile females of the species. Biodiversity means resilience means sustainability. What is our plan for our descendants?

Yet Another Dam?

Here in and about the river valley, we enjoy what could be described as plentiful rainfall, and a pinch of snowfall on occasions. In all, we average about 50 inches a year. Precipitation is generally spread over every month of the year with maximums occurring in the spring and early winter months. For the time being, we have sufficient water for both agriculture and drinking water, but this will change in the future. Growth alone will mean that we need to expand our drinking water supplies.

If the projections of computer models continue to correctly predict changing climate, we’re in for more trouble. Generally, global warming should mean more rainfall as warmer air can hold more moisture, but computer modeling predicts changing weather patterns with less rainfall in mid-continental regions and more on the coasts. Further confounding the issue of water availability is the prediction that what precipitation we do get will come in more intense and less frequent storm events.

Even if we get the same amount of precipitation, but it occurs less frequently, we will need more reservoir capacity to tide us over between rain events. Where will we get our drinking water in the future? In the 1980s City Corp looked to the North Fork of the Illinois Bayou as a possible site for a reservoir. Objections from the environmental community and the Ozark National Forest shifted the attention to the current site on Huckleberry Creek. The watershed of Huckleberry Creek is not large enough, but the reservoir is supplemented by pumping water out of the Illinois Bayou.

This “off-stream pumped storage” option has served the River Valley well for a couple of decades, but now City Corp is looking again to expand its supply by seeking an impoundment on the North Fork. Aside from environmental groups’ objections, and reservations on the part of the National Forest to cede land, there is the considerable expense of constructing a dam. If constructed this impoundment will flood a near pristine area currently used for hunting, fishing, camping, and other water sports.

And when this small impoundment’s capacity is exceeded, then what is the next valley to be flooded? And the next and the next? Ultimately the real long-term solution is to draw water from Lake Dardanelle. Why don’t we just cut to the chase and avoid the costs, both fighting with environmental groups and the monetary cost of construction of dams.

Water in Lake Dardanelle is good quality and can be further refined if necessary by technology. Reverse Osmosis (RO) is employed around the world to turn seawater in the potable water. RO systems are scaled from under the sink units for homeowners to multi-million gallons per day systems for municipal desalination plants.

The Arkansas Department of Health frowns on the utilization of the Arkansas River as a drinking water supply, but their objections are based on old data, and failure to recognize drastic improvements in the cost and efficiency of Reverse Osmosis technology.

Minimally treated water from lake Dardanelle could be pumped to the current Huckleberry Creek reservoir at a fraction of the cost of building more impoundments. This solution will allow us to have the drinking water we need for an expanding population under pressure from global warming. At the same time, we can save some of our wild places so our children and their children can have the experience of a relatively unexploited environment, the same as we enjoy.