How Do Aquatic Plants Survive in a Mediterranean Biome?

Water Temperatures

• Water temperatures in the Mediterranean vary depending on the season of the year and the location. During the winter, water temperatures in a Mediterranean biome can range from 55 to 64 degrees Fahrenheit, and summer water temperatures rise to between 69 and 82 F. Most aquatic plants in the Mediterranean biome, including green algae, prefer water temperatures between 68 and 86 F for optimum growth. The lethal low temperature for Mediterranean aquatic plants is usually 45 to 57 F, and waters above 90 degrees also prove deadly.

Sunlight

• Similar to aquatic plants in other biomes, aquatic plant species adapted to Mediterranean climates require a substantial amount of sunlight to live. Mediterranean aquatic plants with roots tend to thrive in shallow lakes that are 5 to 10 feet deep. Floating plants in Mediterranean biomes do not have roots, so they benefit from sunlight no matter how deep the water is. Without sunlight, these plants cannot engage in photosynthesis, which is the process by which the plants produces their food.

Cultivation

• When cultivating aquatic plants in a Mediterranean biome, choose the right amount of potting soil and follow correct planting procedures. For example, the University of Maryland Cooperative Extension recommends using heavy soil with a high amount of clay for aquatic plants. Organic soil is not good for aquatic plants since this type of soil floats to the top of water and does not help anchor the roots. When aquatic plants are in a pot, weigh down the roots with stones and keep the soil moist. Lower the pot into the water in a location where the plant receives at least three to five hours of sunlight.

Species

• Mediterranean biomes throughout the world are home to about 450 aquatic plant species, which include submerged, emergent and floating species. Submerged plants are those that live completely underwater, while floating plants have leaves and flowers resting on the water's surface. Emergent aquatic plants have root systems underneath the water but some of the plant's stems “emerge” above the surface. Some aquatic plants found in Mediterranean biomes are white lotus, water pennywort, water hyacinth and Neptune grass. The lotus, pennywort and hyacinth are floaters, while Neptune grass is emergent. Another Mediterranean aquatic plant, green algae, is submerged.