Taiga Biome:boreal forests

      Taiga Biome:boreal forests

        

              Taiga is the world's largest land biome, and makes up 29% of the world's forest cover. the largest areas are located in Russia and Canada. The taiga is the terrestrial biome with the lowest annual average temperatures after the tundra and permanent ice caps. Extreme winter minimums in the northern taiga are typically lower than those of the tundra. The lowest reliably recorded temperatures in the Northern Hemisphere were recorded in the taiga of northeastern Russia. 

               The growing season, when the vegetation in the taiga comes alive, is usually slightly longer than the climatic definition of summer as the plants of the boreal biome have a lower threshold to trigger growth. In Canada, Scandinavia and Finland, the growing season is often estimated by using the period of the year when the 24-hr average temperature is 5 °C or more. For the Taiga Plains in Canada, growing season varies from 80 to 150 days, and in the Taiga Shield from 100 to 140 days. Some sources claim 130 days growing season as typical for the taiga.Other sources mention that 50–100 frost-free days are characteristic. Data for locations in southwest Yukon gives 80–120 frost-free days. The closed canopy boreal forest in Kenozyorsky National Park near Plesetsk, Arkhangelsk Province, Russia, on average has 108 frost-free days.The longest growing season is found in the smaller areas with oceanic influences; in coastal areas of Scandinavia and Finland, the growing season of the closed boreal forest can be 145–180 days.

            Animals found in taiga include woodpeckers, hawks, moose, bear, weasel, lynx, fox, wolf, deer, hares, chipmunks, shrews, and bats. Mammals living in the boreal forests have all adapted in various ways to survive the long cold winters. Generally they have heavy fur coats and many hibernate through the winter.

Growthform Adaptations: The main reasons firs, sprucs and pines are the dominant trees in the boreal forest, and thus define the biome is because they are adapted to the extreme conditions brough about by the cold, including the winter-induced drought and the short growing season. The following are some of the main adaptations we found that trees in this zone have:

• Conical shape - promotes shedding of snow and prevents loss of branches.
• Needleleafs - narrow leaves reduce surface area through which water can be lost (transpired), especially in the winter when the frozen ground prevents plants from replenishing their water supply. The needles of boreal conifers also have thick waxy coatings--a waterproof cuticle--in which stomata are sunken and protected from drying winds.
• Evergreen habit - retention of foliage allows plants to photosynthesize as soon as temperatures permit in spring, rather than having to waste time in the short growing season merely growing leaves. [Note: Deciduous larch are dominant in areas underlain by nearly continuous permafrost and having a climate even too dry and cold for the waxy needles of spruce and fir.]
• Dark color - the dark green of spruce and fir needles helps the foliage absorb maximum heat from the sun and begin photosynthesis as early as possible.

Coniferous forest biome

Coniferous forest biome

                Coniferous forest ecosystems are found in regions of the Earth that experience somewhat long and cold winters, with summer being much shorter. Thus, it is no surprise that these biomes are more common the closer one travels towards the Earth’s poles. Additionally, this biome is found high atop mountains where temperatures tend to be lower and winter tends to last longer.
              The Coniferous Forest is a forest of Conifers. A Conifer is a tree that produces its seeds in cones.  The Pine tree is the most common example.  Conifer leaves conserve water with the thick, waxy layer that covers their leaves, also known as needles.  The vegitation in the Coniferous forest is small in size, but large enough to feed the vast herbivore population.  Most of these animals survive the brutal winters by migrating or hibernating. 

                       

Average Annual Rainfall- 14-29.5 in.

Average Temperatures in the Summer- 57.2°F

Average Temperatures in the Winter- 14°F

Temperate coniferous forest         

Temperate coniferous forest is a terrestrial biome found in temperate regions of the world with warm summers and cool winters and adequate rainfall to sustain a forest. In most temperate coniferous forests, evergreen conifers predominate, while some are a mix of conifers and broad leaf evergreen trees and/or broad leaf deciduous trees. . Coniferous forests can be found in the United States, Canada, Europe, and Asia. Many species of trees inhabit these forests including cedar, cypress, douglas-fir,pine, podocarpus, spruce, redwood and yew. The understory also contains a wide variety of herbaceous and shrub species.

Broadleaf biome

Tropical And Subtropical Dry Broadleaf Forest

      The tropical and subtropical dry broadleaf forest biome, also known as tropical dry forest, is located at tropical and subtropical latitudes. Though these forests occur in climates that are warm year-round, and may receive several hundred centimeters of rain per year, they have long dry seasons which last several months and vary with geographic location. These seasonal droughts have great impact on all living things in the forest.

     Deciduous trees predominate in most of these forests, and during the drought a leafless period occurs, which varies with species type. Because trees lose moisture through their leaves, the shedding of leaves allows trees such as teak and mountain ebony to conserve water during dry periods. The newly bare trees open up the canopy layer, enabling sunlight to reach ground level and facilitate the growth of thick underbrush. Trees on moister sites and those with access to ground water tend to be evergreen. Infertile sites also tend to support evergreen trees. Three tropical dry broadleaf forest ecoregions, the East Deccan dry evergreen forests, the Sri Lanka dry-zone dry evergreen forests, and the Southeastern Indochina dry evergreen forests, are characterized by evergreen trees.

     Though less biologically diverse than rainforests, tropical dry forests are home to a wide variety of wildlife including monkeys, deer, large cats, parrots, various rodents, and ground dwelling birds. Mammalian biomass tends to be higher in dry forests than in rain forests, especially in Asian and African dry forests. Many of these species display extraordinary adaptations to the difficult climate.

        This biome is alternately known as the tropical and subtropical dry forest biome or the tropical and subtropical deciduous forest biome. Locally some of these forests are also called monsoon forests, and they tend to merge into savannas

Temperate Broadleaf Deciduous Forest

         The Temperate Broadleaf Deciduous Forest (TBDF)--especially in eastern North America, where is remains most intact--is known for the turning of the colors of its leaves to brilliant reds, oranges, and golds in autumn. The shortening days of fall stimulate the plants to withdraw chlorophyll from their leaves, allowing a brief but beautiful display of other pigments before the leaves are shed completely and plants enter an extended period of dormancy.

Climate: Associated with warmer continental and humid subtropical climates (Dfa, Cfa, and--in Europe, Cfb). There is an approximately 6 month growing season. The 20 to 60 inches of precipitation is distributed evenly throughout the year. The non-growing season is due to temperature-induced drought during the cold winters.

Vegetation: Many of the same genera, previously part of an Arcto-Tertiary Geoflora, are common to all three of the disjunct northern hemisphere expressions of this biome. Included among these genera are Quercus (oak), Acer (maple), Fagus (beech), Castanea (chestnut), Carya (hickory), Ulmus (elm), Tilia (basswood or linden), Juglans (walnut), and Liquidamber (sweet gum). Different species of these genera occur on each continent.

Fauna: Characteristic members of the fauna are either mast-eaters (nut and acorn feeders) or omnivores. Mammals show adaptations to an arboreal life; a few hibernate during the winter months.

• North American herbivores include white-tail deer, gray squirrel, and chipmunk.
• Omnivores include raccoon, opossum, skunk, and black bear.

Carnivores have been largely eliminated through the deliberate effort of humans but should include timber wolves, mountain lions, and bobcats. The coyote, native to the western grasslands and deserts, has recently dispersed east and taken over the niche of its departed cousin, the timber wolf.

Major biomes

Wetland biomes

             Wetlands are areas of standing water that support aquatic plants. Marshes, swamps, and bogs are all considered wetlands. Plant species adapted to the very moist and humid conditions are called hydrophytes. These include pond lilies, cattails, sedges, tamarack, and black spruce. Marsh flora also include such species as cypress and gum. Wetlands have the highest species diversity of all ecosystems. Many species of amphibians, reptiles, birds (such as ducks and waders), and fur bearers can be found in the wetlands. Wetlands are not considered freshwater ecosystems as there are some, such as salt marshes, that have high salt concentrations—these support different species of animals, such as shrimp, shellfish, and various grasses.

              The wetland biome is one that many people don’t really see as being important. In fact, in many areas they consider it to be a nuisance. Swampland is the most common type of wetland biome you will find. They also include marshes and bogs and they can be various sizes. Some of them are very long and deep. Others are nothing more than a few feet of water in a given location but they are still very important.

             In a wetland biome the water is always going to be standing still. You will find them in many low lying areas. It is common for them to be very close to lakes, rivers, and streams. They may have water in them all the time or only during particular times of the year. That is a key factor that separates it from other forms of biomes. The combination of both land and water are essential for this biome to form.

              They help the environment to be better due to the fact that they have a natural supply of water. They help to prevent flooding in many locations as they are able to take on excess water from the other sources. However, when a river or lake is low they can also release water back into them. They also have the natural ability to purify surface water.

              Plant matter is released into freshwater biomes from a wetland biome. The importance of this is that it allows for fish to have plenty of types of food for them to survive. Florida has one of the largest wetland biomes in the world. The humid conditions are perfect for such forms of plant and animal life to be able to survive.

Characteristics

             In a wetland biome the conditions are always very moist and humid. What you will find with characteristics can be very specific to a given location. That is because the wetland biome is so frequently going to overlap with or be a part of other biomes out there. Without this particular one though many others wouldn’t be able to thrive as they do.

             The only places on Earth where you won’t find the wetlands biome are around the Artic. The tundra there is too cold and frozen for them to develop. Just about every other biome though is associated with them in some way. In fact, many times the wetland biome is overlooked by people due to where it happens to be located. Experts though know what to look for and have been able to fully identify them.

             Wetland biomes can be made up of freshwater or saltwater. In some regions they are actually a combination of both. The type of water that is found in it will strongly affect the types of life that are able to survive there. The delicate ecosystems in place around these areas are very detailed. When you take the time and effort to examine them closely you will be very surprised by what you find.

Flora and Fauna

             It may surprise you to discover that the wetland biome has more diversity than any other biome out there when it comes to animal life. There are plenty of animals that find this to be the perfect home for them. They have the right climate, access to food, and the shelter they need for survival. Amphibians and reptiles due very well in this type of environment. They include frogs and lizards.

             Birds are also found in this type of environment. Many of them live there all year long. Others will be there for part of the year and then migrate. There are also those that stop to feed along a route to a new location in the wetland biome. With some species of birds it is found that they move from one wetland biome to the next along their migration patterns.

               Alligators and crocodiles are the largest animals found in the wetland biome. In some wetland biomes there is salt content in the water. When that is the case you may find some more diversity in those locations. Those living creatures include shrimp and shellfish.

              Beavers, minks, and rats are the fur bearing creatures you may find around a wetland biome. The size of them and the location will depend on many factors. For the beaver it will be determined by if they have enough for food. They also need various materials to build a dam from for shelter.

              Plant life that grows in the wetland biome are referred to as hydrophytes. They include pond lilies, cattails, tamarack, and blue spruce. Sometimes cypress and gum will be present too but it will depend on the actual location of the habitat. There are numerous types of grasses that grow in a wetland biome. Sometimes shrubs with fruits including the cranberry can be found in these locations.

Major biomes

Desert biome

              Deserts cover about one fifth of our planet, and are caused by extremely low rainfall over an area.  Theses biomes are nonetheless home to many plants and animals which have through the course of their evolution adapted to this dry environment.

              Hot and Dry Desert is, as you can tell from the name, hot and dry. Most Hot and Dry Deserts don't have very many plants. They do have some low down plants though. The only animals they have that can survive have the ability to burrow under ground. This is because they would not be able to live in the hot sun and heat. They only come out in the night when it is a little cooler.

              A cold desert is a desert that has snow in the winter instead of just dropping a few degrees in temperature like they would in a Hot and Dry Desert. It never gets warm enough for plants to grow. Just maybe a few grasses and mosses. The animals in Cold Deserts also have to burrow but in this case to keep warm, not cool. That is why you might find some of the same animals here as you would in the Hot and Dry Deserts.

              Deserts cover about one fifth of the Earth's land surface. Most Hot and Dry Deserts are near the Tropic of Cancer or the Tropic of Capricorn. Cold Deserts are near the Arctic part of the world.

               Hot and Dry Deserts temperature ranges from 20 to 25° C. The extreme maximum temperature for Hot Desert ranges from 43.5 to 49° C. Cold Deserts temperature in winter ranges from -2 to 4° C and in the summer 21 to 26° C a year.

              The precipitation in Hot and Dry Deserts and the precipitation in Cold Deserts is different. Hot and Dry Deserts usually have very little rainfall and/or concentrated rainfall in short periods between long rainless periods. This averages out to under 15 cm a year. Cold Deserts usually have lots of snow. They also have rain around spring. This averages out to 15 - 26 cm a year.

               Hot and Dry Deserts are warm throughout the fall and spring seasons and very hot during the summer. the winters usually have very little if any rainfall. Cold Deserts have quite a bit of snow during winter. The summer and the beginning of the spring are barely warm enough for a few lichens, grasses and mosses to grow.

              Hot and Dry Deserts vegetation is very rare. Plants are almost all ground-hugging shrubs and short woody trees. All of the leaves are replete (packed with nutrients). Some examples of these kinds of plant are Turpentine Bush, Prickly Pears, and Brittle Bush. For all of these plants to survive they have to have adaptations. Some of the adaptations in this case are the ability to store water for long periods of time and the ability to stand the hot weather.

                Hot and Dry Deserts animals include small nocturnal (only active at night) carnivores. There are also insects, arachnids, reptiles, and birds. Some examples of these animals are Borrowers, Mourning Wheatears, and Horned Vipers. Cold Deserts have animals like Antelope, Ground Squirrels, Jack Rabbits, and Kangaroo Rats.

Coastal and Cold desert

               Coastal deserts are found in areas that are moderately warm to cool, such as the Neotropic and Nearctic realm. The winters are usually cool and short, while the summers are long and warm  The soil is mostly sandy with a high alkaline content, it is also very porous, so rain seeps quite rapidly into the ground.  Most of the flora in the coastal desert features thick foliage, with  good water retention, and their roots are close to the surface of the ground in order to get enough water before it drains into the soil.

               Cold Desert's plants are scattered. In areas with little shade,about 10 percent of the ground is covered with plants. In some areas of sagebrush it reaches 85 percent. The height of scrub varies from 15 cm to 122 cm. All plants are either deciduous and more or less contain spiny leaves.

               Animals of the coastal desert include rough skinned amphibians, birds of prey, scavenger mammals reptiles and insects; most have adapted quite well to the climate, and again, they are largely nocturnal during the warmer months.

               Perhaps the strangest of all desert biomes is the cold desert, as our perception of the desert is usually associated with the heat of the sun.  But even if there is a moderately high amount of snow and rainfall during the wintertime, the soil is too heavy and alkaline.  Alluvial fans pull some of the salt through the porous soil, so plant life can survive, but then again, as with its arid counterparts, the cold desert offers less than ideal conditions for sustaining delicate plants and animals.

             Most of the animals in the cold desert are burrowers, even the carnivores and reptiles which even though cold-blooded, have made their homes in the cold desert.

            Deer and other larger herbivores are only found during the winter, as the supply of grass is more abundant during that period.

Semi Arid Deserts

             The major deserts of this type include the sagebrush of Utah, Montana and Great Basin. They also include the Nearctic realm (North America, Newfoundland, Greenland, Russia, Europe and northern Asia). The summers are moderately long and dry and like hot deserts, the winters normally bring low concentrations of rainfall. Summer temperatures usually average between 21 - 27° Centigrade. Temperature do not normally go above 38° Centigrade and evening temperatures are cool, at around 10° Centigrade. Cool nights help both plants and animals by reducing moisture loss from transpiration, sweating and breathing.

Animals that live in the Desert Biome

          Different animals live in the different types of deserts. Animals that live in the desert have adaptations to cope with the lack of water, the extreme temperatures and the shortage of food. To avoid daytime heat, many desert animals are nocturnal. They burrow beneath the surface or hide in the shade during the day, emerging at night to eat. Many desert animals do not have to drink at all, they get all the water they need from their food. Most desert animals are small.

         Rarer, but important, are physiological adaptations such as aestivation (dormancy during summer), the absence of sweat glands, the concentration of urine, localized deposits of fat in tails or humps and salt glands to secrete salt without loosing fluids.

          Reptiles with their waterproof skin, production of uric acid instead of urine, hard-shelled eggs and ability to gain body heat directly from the sun and to retreat to shade or underground to avoid heat are exceptionally well adapted to dry lands and, not surprisingly, diverse there.

             There are relatively few large mammals in deserts because most are not capable of storing sufficient water and withstanding the heat. Deserts often provide little shelter from the sun for large animals. The dominant animals of warm deserts are non mammalian vertebrates, such as reptiles.

Desert plants

            Desert plants are uniquely adapted to life in a harsh and sometimes extreme environment. They often look unusual, and are sometimes quite beautiful. While desert plants are often greatly enjoyed in nature, they are also experiencing a growing popularity among landscapers. The same traits which allow desert plants to endure in the desert also make them suitable for low water gardening and xeriscaping. In hot, dry climates, desert plants can be used to assemble a striking and very water efficient garden. In cooler regions, desert plants sometimes do well in greenhouse conditions.

             Several traits set desert plants aside from others. The first is that they tend to be designed to store water, and to use water efficiently. Cacti and succulents, for example, both have dense flesh which is designed to store large amounts of water. Many plants also have long roots to reach deep into the water table for water. Other plants deal with hostile conditions by dying off during extreme weather, and reviving during the rainy season to briefly bloom and scatter seeds. During this small window of time, many visitors come to see the profusion of desert wildflowers.

              Many people associate cacti and succulents with the desert, but there are also a range of other plants. Desert wildflowers such as cliffrose, primrose, chuparose, brittlebush, sagebrush, sand verbena, yellow beeplant, and woolly daisies are common. There are also desert versions of familiar flowers like marigolds, lupines, poppies, sunflowers, chicory, mallow, dandelion,a and lily. During their blooming season, these wildflowers light up the desert with color.

           Deserts also host an assortment of trees and shrubs such as creosote bush, crucifixion bush, desert willow, elephant trees, mesquite, ponderosa pines, Joshua trees, and acacias. Many of these trees have minimal foliage, since water loss through leaves is undesirable for them. They may also be bedecked in thorns to discourage hungry animals, and they often have thick, fleshy trunks and branches.

Major biomes 

Forest ecosystem

 Forest Ecosystem       

           
            A  is a terrestrial unit of living organisms (plants, animals and microorganisms), all interacting among themselves and with the environment (soil, climate, water and light) in which they live. The environmental "common denominator" of that forest ecological community is a tree, who most faithfully obeys the ecological cycles of energy, water, carbon and nutrients.

           A forest ecosystem would be considered having boundaries and would include a forest of trees out to the limit of tree growth. Remember that forests are not the only ecosystems. There are hundreds of thousands of defined and undefined ecosystems that can cover the broadest to the tiniest of areas. An ecosystem can be as small as a pond or a dead tree, or as large as the Earth itself.

              The forest ecosystem covers the flora, fauna and ground conditions with in the parameters of a forest. From the climatic conditions to the members and relationships in the food chain, the forest ecosystem is dependent on the major resources available. In the forest ecosystem the proportion of flora, including the varieties of trees, grasses, fungi and flowers will effect the way in which fauna exist.

      

           The fauna in a forest ecosystem will include the minute and the massive. The forest ecosystem offers shelter and living conditions to insects, birds, arachnids and mammals, from the tiny bush mouse to the largest primate or predator.

A Healthy Forest Ecosystem

             In the forest ecosystem the smallest creatures and plants are still important to the structure of the environment. From the smallest gnat to the largest predator, the relationship between the food chain is vital to the balance of the ecosystem. In the way that grass feeds cattle so too do smaller creatures become food for larger. Even the plants of the forest will become fodder for larger herbivores or small creatures. The forest ecosystem is balanced by the resources available. The number of trees, fungi, grass or flowers will be, maintained by the number of animals or insects using them for their lifestyle or food sources. If the number of predators in the forest ecosystem should alter, then the food chain would be unbalanced right down to the fundamental level. Even a slight alteration in the forest ecosystem, due to floods or drought or human intervention, can lead to the destruction of the forest ecosystem itself.

Forest ecosystem concepts:

                Often forest ecosystems are studied in watersheds draining to a monitored stream: the structure is then defined in vertical and horizontal dimensions. Usually the canopy of the tallest trees forms the upper ecosystem boundary, and plants with the deepest roots form the lower boundary. The horizontal structure is usually described by how individual trees, shrubs, herbs, and openings or gaps are distributed. Wildlife ecologists study the relation of stand and landscape patterns to habitat conditions for animals.

                 Woody trees and shrubs are unique in their ability to extend their branches and foliage skyward and to capture carbon dioxide and most of the incoming photosynthetically active solar radiation. Some light is reflected back to the atmosphere and some passes through leaves to the ground (infrared light). High rates of photosynthesis require lots of water, and many woody plants have deep and extensive root systems that tap stored ground water between rain storms. Root systems of most plants are greatly extended through a relation between plants and fungi, called mycorrhizal symbiosis.

                

           The biomass of a forest is defined here as the mass of living plants, normally expressed as dry weight per unit area. Biomass production is the rate at which biomass is accrued per unit area over a fixed interval, usually one year. If the forest is used to grow timber crops, production measures focus on the biomass or volume of commercial trees. Likewise, if wildlife populations are the focus of management, managers may choose to measure biomass or numbers of individual animals.

Our ecosystem