To mitigate this problem, deciduous trees develop physical and internal adaptations sparked by variations in the climate. Limited sunlight and cooler temperature are the conditions that trigger deciduous trees to develop adaptation. In autumn, when these climatic conditions take place, the trees disconnect the supply of water to leaves and close off the area occurring between the tree trunk and the leaf stem.
With insufficient supply of water and sunlight, the leaf becomes incapable of generating chlorophyll the green pigment found in leaves. As the level of chlorophyll goes down, the leaves change their color. The scintillating display of bright red, gold and yellow leaves associated with deciduous forests in the autumn is due to this process. Most of the trees in this biome drop off their leaves the moment they become brown and dry.
Deciduous rainforest biome is a home to a variety of reptiles, mammals, birds, and insects. Examples of mammals living in deciduous rainforest biome include raccoons, skunks, bears, squirrels, and wood mice. In the United States, you can find deer in this biome. Although coyotes, bobcats, Timberwolves and mountain lions naturally exist here, humans have almost eliminated all of them due to their threat to human life.
Reptiles, amphibians, and insects also thrive here. The wet climate and considerably warm temperatures of the deciduous forest make it an awesome habitat for numerous amphibian and reptile species that cannot survive in colder climatic conditions. Salamanders, Wood Frogs, and Toads mainly live on the forest floor. Most adopt camouflage tendencies to look like dead, decomposing leaves that cover the ground. Reptiles like rat snakes and box turtles also exist here. Different insect species also live in this biome.
Tree leaves are rich sources of food for butterfly and moths. The tree woods are home to carpenter bees and termites. Walking sticks and katydids synchronize with the greenery and cicadas spend the greater part of their lives holed underground with roots of plants being their main source of food. Animals living in this kind of biome have developed two types of adaptation: hibernation and migration.
Hibernation is a state of inactivity. Migration is the movement of animals from freezing climatic conditions to more favorable climatic conditions. While huge arrays of birds migrate, most mammals hibernate in winter when food is inadequate. Another unique adaptation many animals have developed is food storage. The Deep South competes with the Pacific Northwest as the rainiest region in the country but is much more biologically diverse because it is warmer.
The waters of the Gulf of Mexico are an important factor in Alabama's climate, especially the influence of the Loop Current. Throughout the year, this current enters from the Caribbean Sea between Cuba and the Yucatan Peninsula, heads north toward Alabama, then bends to the southeast and exits the Gulf via the Florida Straits.
In the process, the Loop Current delivers warm tropical waters to Alabama's doorstep. Evaporation from the northern Gulf provides water vapor that falls on the state as rain throughout the year. A glance at any world map will reveal that deserts are usually found at Alabama's latitude. Because of the Gulf of Mexico, however, Alabama and its neighboring states are lush and green.
Cahaba Indian Paintbrush High levels of heat and moisture can also produce volatile weather patterns, but these, too, enhance the state's species biodiversity. Convective storms generate lightning, and the resulting wildfires have kept the Southeast burning for thousands of years. The role that fire plays in shaping the biodiversity of the region cannot be overstated. Prior to statehood, a combination of Native American landscape management and lightning-sparked fires meant that most of the state would burn at least once a decade, often more.
These fires maintained prairies and open woodlands and prevented fast-growing shrubs and trees from overtaking ecosystems. The plentiful sunlight reaching the ground supported hundreds of less-competitive, sun-loving species, especially wildflowers and grasses. These species evolved strategies to cope with the frequent, low-intensity fires. Within the longleaf pine woodland Alabama's most widespread native ecosystem , it is possible to find more than 30 fire-adapted species per square meter of soil.
Alabama's rich geologic diversity has shaped the state's ecosystems and biodiversity even more than climate. Variations in soil types, bedrock exposure, and topography regulate biological productivity by affecting the availability of heat, light, water, and nutrients.
In general, regions with more geologic variation have more species. Alabama has a high degree of geologic variation relative to most other southeastern states because of the many rock types uplifted by the rise of the Southern Appalachian Mountains during the final million years of the Paleozoic Era million years ago.
Demopolis Chalk Alabama has many unique ecosystems made possible by its variety of soils. For example, the quartz sand deposits along the coast support dune communities sparsely populated by grasses and shrubs.
Though rain frequently drenches the coast, water quickly drains through the dune sand, and the resulting ecosystem is more akin to desert than any other ecosystem in the state. In contrast, the marine chalks of the Blackland Prairie region supported tallgrass prairies before they were converted to cotton plantations.
Trees were kept out by frequent fire and the dense chalk, which was nearly impenetrable to tree roots and groundwater. Instead, grasses and wildflowers more typical of the tallgrass prairies of the Great Plains presided. Leafy Prairie Clover Scattered throughout Alabama's coastal plains are seepage bogs, wetlands created by groundwater forced to remain on the surface by a thick layer of nonporous clay. These sunny wetlands support wildflowers, grasses, and most of the state's carnivorous plant species.
Alabama's glade ecosystems offer the most dramatic example of the connection between geology and biological diversity. Found in the mountainous region of the state, glades are open, sunny ecosystems where the bedrock is at the surface or covered with extremely thin soils.
Because trees struggle to gain a foothold, the soils support rare and unusual wildflowers that can tolerate the harsh conditions.
Most glade plants complete their growth and reproduction in a few weeks in late spring, before the glades become unbearably hot. Glade types are named for their bedrock and Alabama glades include limestone, dolostone, sandstone, and granite. Each rock type weathers into a unique soil and supports a distinct assemblage of plant species. Geologic processes also created the state's diverse topography , the arrangement of surface features such as mountains, plains, and rivers.
Alabama's terrain ranges from the flat Coastal Plain section to the rugged peaks of the Valley and Ridge section in the state's northeast. Each of Alabama's five physiographic sections has a distinctive topography, and this variation promotes ecological and species diversity. Each province supports its own distinctive set of soils and topography, and consequently, a distinctive community of plants and animals.
Wills Valley In the southern Cumberland Plateau section, for example, different rates of erosion have produced a template upon which many varied ecosystems survive side by side. Broad mountains with relatively flat upper surfaces—including Sand and Lookout Mountains—dominate the landscape.
These plateaus persist because a cap of sandstone a very durable rock underlies the surface and resists erosion. The valleys adjacent to the plateaus exist where the sandstone cap fractured as the Southern Appalachian Mountains grew. Water eroded the fragments away, then cut downward through the shale, limestone, and other soft rocks beneath.
Elf Orpine Flowers Up on the plateau surface, weathering of the sandstone produces well-drained sandy soils. Before white settlers arrived and cleared them for agriculture, the plateau surface supported dry, open woodlands through which wildfire burned once or twice a decade. Shortleaf pine and a handful of fire-tolerant oak species dominated.
The number of documented butterfly species rivals and surpasses that of most states. Alabama has high mountainous ridges and deep valleys, foothills of the Appalachians, Black Belt prairie, flat coastal plains, river deltas, lakes, springs, huge cave systems, swamps, Gulf and bay coastlines, and barrier islands.
All of this land diversity is drained by numerous river systems, with the mighty Tennessee River coursing through the northern one-fifth of the state. Four-fifths of that portion of the state below the Tennessee River is drained by several major rivers flowing southwestward into Mobile Bay, together forming the Mobile River Basin.
A few isolated river basins occur along the southern boundary of the state and empty directly into the Gulf of Mexico, while others empty into the Choctawhatchee, Escambia and Pensacola Bays Fig.
The Fall Line roughly follows the ancient shoreline of the seas that covered this region during the Cretaceous Period known as the Mississippi Embayment. The Fall Line plays an important role in animal and plant distribution in Alabama. Lowland species often do not cross the Fall Line into the uplands. Recently, Griffith et al. Ecoregions are those regions that share certain biotic and abiotic features.
They are similar in the type, quality and quantity of environmental resources such as geology, physiography, vegetation, climate, soils, land use, wildlife and hydrology.
Each of these ecoregions is important when beginning a study on Alabama butterflies. Several species of Alabama butterflies are limited to just one of these regions because of some unique feature of that ecoregion. It extends from the barrier islands such as Dauphin Island eastward to Fort Morgan and the beachfront regions of Gulf Shores to Orange Beach, plus the east, west and north shorelines of Mobile Bay.
It includes estuaries, salt marshes, lagoons, bayous, river deltas, and wetlands. This area receives huge amounts of sediments from the extensive upstate drainage area of the Mobile River Basin.
The area is constantly changing in size and shape due to floods, hurricanes, erosion, and other forces of nature. The Mobile-Tensaw river delta, just north of Mobile Bay, contains extensive swamp lands with hundreds of square miles of cypress trees and hardwoods. This area is mostly an inhospitable region for humans and the environment has been little disturbed by human development. It serves as an important refugium for certain butterfly species.
The coastal areas from Dauphin Island eastward to the beachfront properties around Fort Morgan, Gulf Shores and Orange Beach are presently under intense pressure by condominium developers and others who would alter the natural features of the sand dune community, with its xeric pine flatwoods and salt marsh habitats.
The land in this region is relatively flat but includes some areas with low rolling hills. The soils are largely sands, sandy loams, red clays and sandy clays with extensive gravel beds near streams and old stream channels. Dominant herbaceous plant species in this area include wiregrasses Aristida stricta and Sporobolus junceus.
Most of the land has been cleared for food crops such as peanuts, cotton, corn, and soybeans, or devoted to intensive loblolly pine-tree farming. Thus, much of the native vegetation on which butterflies depend has been largely replaced in this region with row crops and pine-tree stands Mount, The Palamedes Swallowtail and Delaware Skipper are largely found in this southern portion of the Southeastern Plains ecoregion.
According to Lacefield , the Upper Coastal Plain in Alabama or Upper Southeastern Plains lies just north of the Lower Coastal Plain, extending as a band across the state with its northern boundary immediately south of the Fall Line. This area has rolling hills, flat lands, swamps and a unique geological land form known as the Black Belt which extends, for example, through the towns of Gainesville, Livingston, Demopolis, York, Epps, Selma, Montgomery and Clayton.
While soils in the northern portion are largely sands and clays, the Black Belt is underlain by extensive layers of white chalk.
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