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| | Everything you needed to know about Mangroves
| The mangrove ecosystem Mangrove ecosystems, called "mangals," are very unique. The roots of the mangrove provide ideal habitat for fish and invertebrates such as large game fish, groupers, snappers, archer fish, shrimps, crabs, lobsters, sponges, oysters, and corals. Many juvenile stages of these and other fish develop in these mangrove "nurseries," before moving out into the ocean. Larger animals, including, crocodiles, sea turtles, manatees, snakes, birds, deer, and raccoon also find mangals an ideal habitat. The intricate root systems of the mangroves help to protect coastlines during hurricanes and other tropical storms. |
Mangrove ecosystems are declining, mostly due to human interventions such as increased populations along coast lines, pollution, and cutting of the mangroves for timber and to clear land for palm and sugar cane plantations.
Special adaptations for a saltwater environment Mangroves have special adaptations that allow them to conserve water and regulate their salt levels.
Water conservation The leaves of the mangrove have three characteristics that help conserve water:
Lowering salt levels Different species of mangroves have varying ways to regulate their salt levels.
- Cuticle: The leaf is covered by a cuticle, which gives it a shiny, almost waxy appearance. The cuticle helps keep water in the leaf.
- Stomata: The underside of the leaf has tiny pores, called "stomata. These allow for the exchange of water and carbon dioxide. If necessary, the plant can constrict the openings of the stomata to conserve water.
- Orientation: Many plants orient themselves to take full advantage of the sunlight. Mangroves differ in that, if necessary, they can tip their leaves upward to decrease their exposure to the sun and limit the loss of water through evaporation.
Reproduction Red mangroves have pale yellow flowers, which are pollinated by the wind. Some other species of mangroves are pollinated by insects. Red mangroves reproduce by a process called "vivipary." The seeds that result from the pollination of the flowers start to germinate while they are still attached to the tree. The seedlings, which are called "propagules" (sometimes termed "tuber" in the aquarium industry), remain on the tree until they are ripe. They then fall from the tree and float in the water, for up to a year, until they have contact with a suitable substrate. A propagule is approximately 6 to 8 inches in length and looks similar to a candle.
- Secretion: Some mangroves have small glands on their leaves that can actually secrete excess salt, which can be washed away by the rains.
- Exclusion: The roots of some plants are specially adapted to allow for the passage of water into the plant, but at the same time excluding salt from entering. The Red Mangrove has this type of "salt pump."
- Sequestration: Using a third process, some mangroves can allow salt to accumulate in older leaves, and when the leaves fall off of the plant, the excess salt goes with them. Some mangroves also sequester salt in their bark or roots.
Mangroves in an aquarium
- Acquiring your mangrove: If you wish to include mangroves in your aquarium, give careful consideration to their origin. Purchase plants that were grown in nurseries, not harvested as a detriment to their ecosystems. Check that they come from a nursery with the correct dealer certificate issued by the state in which they were grown.
- Planting the mangrove: The propagule can be planted in an open topped aquarium, illuminated sump, or refugium. When adding a mangrove propagule to your aquarium, you can plant it directly in the sand or gravel, use a rubber band or tie to attach it to the top of rocks or driftwood, or allow it to take root in the water with no substrate. The roots will quickly take hold in either a sand substrate or in live rock. When planting a mangrove propagule, be sure the growth tip and any leaves present on the plant are out of the water. If you have a canopy over your aquarium, simply plant the tuber towards the back of the aquarium, so it will eventually grow through the area where the plumbing is located.
- Transplanting the mangrove: As with many other plants, moving a mangrove can stress it and cause its leaves to wilt or drop off. If this occurs, place the plant in tap water under strong light. When transplanting a mangrove from freshwater to saltwater, it must be done in increments. Over the course of several days, gradually increase the salt level in the water. Also, be sure there is sufficient magnesium in the water (see Nutrients, below).
- Filtering capabilities: Mangroves can help lower nitrates and phosphates in the aquarium. If you are including mangroves in your aquarium as part of your filtering system, it is best to set up a separate mangrove filter. This can be a 10-20 gallon tank that is placed next to your aquarium and connected to its water circulation system. For small (10-30 gallon) aquariums, you will need to have approximately one plant for every gallon. If you have a larger aquarium (50-200 gallons), the attached mangrove filtering tank will need about 1 plant for every 2 gallons of water. The number of plants needed, of course, depends upon their size.
- Lighting requirements: Mangroves do not need intense light. Light from a sunny window may be sufficient (do NOT place your aquarium in direct sunlight). A supplemental light source such as a fluorescent fixture with two or more grow bulbs with a light spectrum in the range of 6000°-8000°K (Kelvin rating of degrees), or the light from the side of a metal halide fixture can also be used. Allow at least 4 inches between the leaves and the light source to prevent heat injury.
- Temperature and humidity: In areas of low humidity, such as winter in northern climates, mangroves should be misted daily. Since they are tropical plants, they prefer warm temperatures and do not tolerate freezing.
- Nutrients: Red mangroves need adequate amounts of magnesium in the water for their "salt pumps" to work. If magnesium levels become too low, the plants can develop "salt stress," which can cause yellowing of the leaves and shriveling of the leaves and branches. At a specific gravity of 1.025 (normal sea water), the magnesium level should be 1,000-1,300 ppm.
Mangroves receive most of their nutrients from the aquarium water and fish food, and do not need to be supplemented with fertilizers. Use a commercial trace element supplement that contains iron, manganese, and potassium weekly, especially if the aquarium has a large number of mangroves.
- Pest control: Mangroves may become infested with mealy bugs, scales, white flies, or mites. If grown in an aquarium, pesticides cannot be used to control these pests. In these situations, control options include purchasing insects that will eat these pests, or removing the pests by hand.
- General care: The general care for the mangrove plant includes wiping excess salt from the leaves with fresh water a few times per week. Mangroves absorb nutrients from the water in order to grow. They export the unneeded nutrients and excess salt through their leaves. It is important for nutrient control, that when leaves drop from the plant that they not be allowed to decay in the aquarium. Tannins from the decomposing leaves may also turn the water yellowish brown, although small amounts can be removed with an activated charcoal filter.
- Pruning: The Red Mangrove grows very large and tall in nature. To prevent excessive growth in an aquarium, simply trim the growth tip of the plant as necessary with a sharp scissors. In time, the plant will alter its growth, and remain short and bushy. In fact, you can manipulate the growth of your mangrove much like you would a Bonsai Tree.
Do NOT cut or damage the roots of seedlings – it may kill the plant. A wayward root can be trimmed on an older plant.
Article from: http://www.peteducation.com/article....articleid=3133
Last edited by missionsix; 09-07-2009 at 09:41 AM.
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