Water Garden Supplies Bella Vista AR
Annuals, Garden Centers / Nurseries, Plants
Pea Rdg, AR
Annuals, Cactus / Succulent, Garden Centers / Nurseries, Groundcovers, Perennials, Plants, Seed, Shrubs, Wildflower Seed
Annuals, Garden Centers / Nurseries, Plants, Shrubs
Van Buren, AR
The Secret Life of Ponds
Water makes life on the planet not just livable, but possible. All organisms are utterly dependent on it for survival. Our bodies are 80 percent water. It covers three-quarters of the Earth's surface, but only 3 percent of that area is fresh water (the rest is oceanic salt water), and more than half of that is in the form of ice. There are lots of ways to wade into water in schoolyard gardens and habitats: exploring transpiration, experimenting with mulches and other means of conserving water, creating weather stations, restoring wetlands, and assessing the water needs of area wildlife, to name a few. Many teachers have also discovered the value of schoolyard ponds as teaching tools. They can inspire explorations of the life and chemistry of aquatic ecosystems, along with reading, writing, and quiet reflection. So, you have little space? You can create a mini-pond in a corner of a courtyard or even in a half-barrel.A Balanced Equation
As dynamic ecosystems, ponds feature a constant interaction among living and nonliving elements. To be a steward of pond life, you should have a basic understanding of this fascinating chemistry. Here's the (very) short course. First, the players:
Algae, the organisms that form the familiar green pond scum and grow on underwater objects, are neither plant nor animal, but organisms that photosynthesize (produce food and oxygen) using sunlight. They form the basis for aquatic food chains.
Pond plants come in two forms: submerged (those that grow completely under water) and floating-leaved (their leaves lie on top and roots reach to the bottom). The submerged plants, which are the pond's greatest source of oxygen, absorb nutrients through their leaves (competing with algae for light and food) and provide places for fish to hide. The floating-leaved plants take in nutrients through their roots and provide shading that keeps floating algae in check and helps moderate the temperature.
Fish require oxygen, nutrients, and places to hide their eggs. Their waste products, such as ammonia, are absorbed as nutrients by plants (as is and when broken down into nitrates). Snails, tadpoles, and other scavengers eat algae, plant debris, and other once-living matter.
Oxygen and carbon dioxide in the air dissolve into pondwater at the surface and where bubbles cause air and water to mix. During daylight, aquatic plants and algae release oxygen as they photosynthesize. Fish, other animals, and plants, meanwhile, consume oxygen from the water and produce carbon dioxide as they respire. On sunny days, the effects of photosynthesis outweigh the effects of plant respiration, so oxygen increases and carbon dioxide decreases (the opposite is true when sunlight is not available). On very sunny days, your students can look for small bubbles of oxygen gas on the leaves of aquatic plants. Oxygen is also consumed when organic materials, such as animal waste and plants, decompose in water. The pH of pondwater rises on sunny days (...