Saturday, August 13, 2011

Ponds under stress

Bald Cypress near pond
Among the several ecosystems in The Woodlands Texas having to endure the extreme drought of 2011 is the pond. Some of our ponds have Cypress trees like these along the banks. Others have various other types of trees. The Cypress is made to withstand a drought. Although its roots are shallow, it has a built-in defense to hibernate in the summer. This summer is no exception, but it was much earlier and for a longer duration. These trees I personally planted several years ago. They are benefactors of artificial grass watering, as well as nearby water. However, the pond has retreated several feet this summer and caused a stress that these trees had not known before.
Struggling Bald Cypress further from shoreline
Residents and outside visitors who frequent this pond remark about the low water level. They also note the  trees are barely making it this year. In fact, the Parks Dept destroyed at least 8 small trees in the bulrushes, apparently thinking the trees were already dead, when they mowed down the bulrushes. I was glad to see this conspicuous one (which I planted first) still remaining. We all are praying for rain.
Mowed bulrushes and pond ecosystem on left behind homes
This area has long been the home of many turtles, frogs, a water bird estuary, a fish fry estuary, and a butterfly feeding haven. It is a very natural habitat that has taken about 15 years to slowly develop, with the help of the Parks Dept and neighboring residents. If it is not mowed again, it will come back alive once more. Plants are already sprouting along the bank and some of the reedy plants are coming back up by their roots. Normally, the bulrushes provide a sanctuary for almost every living thing in the pond. The bass lay in wait to prey on water creatures along the bank, their offspring feed and hide in the reeds, perch fry hide in it, and a multitude of creatures lay their eggs in it. The dead reeds generally protect the root systems of the live plants until the hot sun gives way to more temperate growing conditions in the Fall. Fortunately, we have an automatic watering system to compensate for the removal of the natural habitat, but that will do little for the fish, frogs, water birds and turtles. Some of our ponds are threatened by oxygen kills (lack thereof). This pond has a large surface for exchanging gases. Algae will take over in some years, so The Woodlands must control the algae. Now as the water recedes from the banks, the threat of algae becomes more intense. Without rain, our ponds suffer from lawn chemicals in water runoffs to the sewer system from irrgating the lawns. Then we have a more concentrated effect of fertilizers and insecticides accompanying lawn water moving down the storm sewers which exit into the ponds'  ecosystem. When we have our normal rainfall, the pond overflows, exiting through a back creekbed and thereby dilutes these pollutants.
Our parks with and without ponds are all under some stress. These four pine trees in this park near the pond have been recently killed by beetles, which have leveraged the weakness of the drought-stricken trees to feed and multiply.

It is not over! The worse could yet come. We have one advantage though, even if it does not rain for another month. The daylight hours are shortening little by little, relieving the sun's intense drying effect. But 102 degrees is still too much for the ecosystem!   

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