Monday, April 27, 2020

Water and Aquatic Habitats free essay sample

It affects terrestrial habitats more than aquatic ones as the range in temperature is much wider in terrestrial habitats. Temperature variations result in both hot and cold climates. The temperatures of temperate terrestrial habitats have markedly seasonal variations with temperatures below 00C in winter and above 200C in summer. Aquatic habitats experience a vertical variation in temperature with a drop in temperature as the depth increases. In tropical marine waters, the temperature at the surface is about 300C while at a depth of 1500 m the temperature is 40C. Organisms differ in their ability to tolerate variations in temperature. Generally, each organism has its optimum temperature at which it can maintain itself. Poikilothermic animals (cold-blooded) become inactive when the temperature falls to about 60C or rises above 400C. If unfavourable temperatures are seasonal or persist for ling periods, these animals tend to aestivate. Homoiothermic animals (warm-blooded) are able to adapt to temperature changes by maintaining a constant body temperature. We will write a custom essay sample on Water and Aquatic Habitats or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page In plants, the rate of photosynthesis and transpiration are affected by temperature. Rainfall Rainfall is another climatic factor that affects mainly terrestrial habitats. Droughts and floods are determined by the amount of rainfall and these can cause the destruction of vegetation covers and as a consequence, community. Rainfall affects the distribution of any kind of vegetation. An annual rainfall of 1600 mm yields an equatorial forest. Rainfall is essential to maintaining the life of freshwater habitats. Lack of rainfall causes drying up of ponds, lakes and streams and consequently death to organisms living there. Plants found living in areas that are aquatic are known as hydrophytes and have adaptations for living in these areas e. g. water lily. Plants found in dry, arid areas are called xerophytes and possess certain adaptations for living there such as stems modified to store water, leaves reduced to spines, sunken stomata and hairy leaves, e. g cactus. Light Light is needed for photosynthesis to take place. It also affects animals in various ways. Some animals like the earthworm, woodlice and bats shy away from light while others are active by day. Exposure to ultraviolet rays enables man to make Vitamin D. Migration of birds is as a result of seasonal shortening of daylight. Hibernation of mammals and changing of coat colour is also regulated by light. Aquatic animals prefer darker waters during the day and ascend to the surface when light intensity is reduced. Flowering of plants also depends on light. pH This determines the acidity or alkalinity of the water in aquatic habitats or the soil in terrestrial habitats. The pH tends to be neutral at a value of 7 and increases if alkaline contents are abundant. Organisms are affected by the pH of their environment. Fresh water mollusks tend to be deficient on waters with a pH less than 6. Wind Winds carry water currents and waves and also rain-bearing clouds.