Geographic Conditions that Favor Biodiversity in the World and Mexico

Biodiversity

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A biome is made of many similar ecosystems. An ecosystem is often much smaller than a biome, although the size varies.

Ecosystems are the interactions between the living things and the nonliving things in a place. In an ecosystem, the plants, animals, and other organisms rely on each other and on the physical environment – the soil, water, and nutrients, for example.

Even though they are living in the same place, each species in an ecosystem has its own role to play. This role is called a niche. The niche for one species might be to climb trees and eat their fruit, while the niche for another species might be to hunt for small rodents. For a tree, a niche might be to grow tall and make food with the Sun’s energy through the process of photosynthesis. If the niche of two species is very similar, they might compete for food or other resources.

Sometimes ecosystems get out of balance. If, for example, it rains a lot and a type of bird that thrives with extra water increases in numbers, other species in the ecosystem might be crowded out. The birds might take food or space or other resources from other species. They might eat all the food. Sometimes an ecosystem naturally gets back into balance. Other times an ecosystem will become more and more out of balance. Today, human actions are having an impact on ecosystems all over the world. Making buildings and roads, fishing and farming all have an impact on ecosystems. Pollution on land, air pollution, and water pollution is sending many ecosystems out of balance too.

 

Tundra

In the very cold places of the world, survival isn't easy. The soil is frozen, its top surface thawing only during summer, and no trees can grow. Yet plants and animals that are adapted for the harsh conditions thrive. This biome is called tundra. Most of the world's tundra is found in the north polar region. It is called Arctic tundra. There is a small amount of tundra on parts of Antarctica that are not covered with ice. Plus, tundra is found on high altitude mountains and is called alpine tundra.

Permafrost is the term given to frozen soil. During the winter months, permafrost reaches the surface of the tundra. It is very cold during the winter, with temperatures reaching -60 degrees Fahrenheit (-51 degrees Celsius). Very few animals are active in these harsh conditions.

In the summer time, the tundra changes. The Sun is out almost 24 hours a day, so the tundra starts to warm up. The permafrost melts at the surface, and plant life grows. However, the permafrost only disappears for a few inches below the surface. There isn't enough soil for trees to grow, so only small plants are found in the tundra.

At the same time, a variety of animals come out to feast on the plants. Insects come to feed on the animals, and birds appear to enjoy the insects.

Taiga

“Taiga” is a Russian word meaning dense evergreen forest. The taiga biome, the largest biome on land, is full of dense evergreen forests. Located just south of the tundra in the northern parts of Europe, Asia, and North America, these forests of conifer trees are also known as boreal forests.

It is very cold and snowy in the taiga during winter, with below freezing average temperatures. While it is not uncommon for temperatures to dive below freezing during the summer as well, it is generally warmer then. Days are long during summer in the taiga, ice thaws, snow melts, and it is often rainy.

Conifer trees like spruce and fir thrive in this climate. The trees grow close together. This protects them from cold and wind. Their dark color makes their albedo low and they absorb solar energy readily, keeping them a bit warmer. There are a few deciduous tree species that can live in the taiga as well including birch and aspen, but they are not common.

Many animals make their home in the taiga for at least part of the year. Some stay year-round. In the summer, birds and insects are abundant. Many bird species migrate to the taiga and breed and nest there during summer. Other birds, such as sparrows and crows, stay in the taiga year-round. Mammals include herbivores like rabbits and voles as well as carnivores such as lynx, wolverines, and bobcats.

Temperate Forests

The temperate forest biome is found in regions where winters are cold and summers are warm. Regions with this climate are common in the mid-latitudes, far from both the equator and the poles. Tropical rainforests are in regions that are consistently warm all year long, close to the equator.

Temperate forests are almost always made of two types of trees, deciduous and evergreen. Deciduous trees are trees that lose their leaves in the winter. Evergreens are trees that keep their leaves all year long, like pine trees. Forests can either have deciduous trees, evergreens, or a combination of both. Another kind of forest is a temperate rain forest. These are found in California, Oregon and Washington in the United States. These forests are made of redwoods and sequoias, the tallest trees in the world.

The amount of rainfall in an area determines if a forest is present. If there is enough rain to support trees, than a forest will usually develop. Otherwise, the region will become grassland.

Coniferous forests

 

Coniferous forests are made up mainly of cone-bearing or coniferous trees, such as spruces, hemlocks, pines and firs. The leaves of these trees are either small and needle-like or scale-like and most stay green all year around (evergreen). All are softwoods able to survive cold termperatures and acidic soil.

Coniferous forests are found mainly in the northern hemisphere, although some are found in the southern hemisphere.

The northern coniferous forests are called taiga or boreal forests. They cover vast areas of North America from the Pacific to the Atlantic, and range across northern Europe, Scandinavia, Russia and across Asia through Siberia and Mongolia to northern China and northern Japan.

Short summers and long winters
Coniferous trees thrive where summers are short and cool and winters long and harsh, with heavy snowfall that can last as long as 6 months. The needle-like leaves have a waxy outer coat which prevents water loss in freezing weather and the branches are soft and flexible and usually point downwards, so that snow slides off them. Larches are one example of a coniferous tree found in some of the coldest regions. Unusually for coniferous trees they are deciduous, that is they shed their leaves in winter.

Coniferous trees such as cypresses, cedars and redwoods are found in warmer regions.

Life on the forest floor
Even evergreen trees eventually shed their leaves and grow new ones. The needles fall to the forest floor and form a thick springy mat. Thread-like fungi help to break down or decompose the fallen needles. These fungi provide nutrients from the decomposed needles back to the roots of the trees. But because pine needles do not decompose easily, the soils are poor and acid.

These forests grow under widely differing conditions of climate and soil - from the tropics to the subarctic, and from heavy clays to poor sands. However, coniferous trees are especially conditioned to the winter climate. The trees of the taiga grow at the highest latitude of any forest. The most common are spruce, pine and firs.

Reach for the sky!
Cypresses, cedars and redwoods grow upright; the tallest of them can reach 20m in height. The trees are usually pyramid-shaped. Short, lateral branches grow quite close together but they are so flexible that the snow simply slides off. The leaves are small, hard and evergreen.

Little light penetrates the thick canopy of trees to reach the forest floor. Because of this gloom, only ferns and a few herbaceous plants grow here. Mosses, liverworts and lichens are also found on the forest floor and grow on tree trunks and branches. There are few flowering plants.

 

Tropical Rainforests

Tropical rainforests are home to thousands of species of animals, plants, fungi and microbes. Scientists suspect that there are many species living in rainforests have not yet been found or described.

There are areas of rainforests where plants are densely packed. Areas where sunlight can reach the surface are full of interesting plants. In other areas a canopy, made from the branches and leaves of tall trees, shades the ground below, preventing smaller plants from growing.

Rainforests get their name because they receive a lot of rain - an average of 80 inches (203 cm) a year! Rainforests are found at and near the equator, where it is always warm and muggy. The temperature doesn't change very much during the year.

The Desert

Deserts are full of interesting questions. How can anything survive in a place with hardly any water? Why is it so dry to begin with?

You can find at least one desert on every continent except Europe. Each desert is different in some way, but they all have one thing in common. In order for an area of land to be considered a desert, it must receive less than 10 inches of water a year.

Clouds are scarce in deserts. Without clouds, there can't be rain, snow, or any other precipitation. Clouds also shade the land, so without them, the desert gets mighty hot as the Sun beats down during the day. At night, the desert can become very cold, because there isn't moisture in the air to hold onto the heat.

The geology of each desert is unique. Some deserts have sand dunes - great waves of sand weathered from rock, that move over time as wind blows the sediment. Other deserts have no dunes but instead have unique rock formations carved by wind and streams that only flow at times when there is moisture.

Many plants and animals survive in these vast, dry lands. Learn more about life in the desert by exploring the links below

Grasslands

Over one quarter of the Earth's surface is covered by grasslands. Grasslands are found on every continent except Antarctica, and they make up most of Africa and Asia. There are several types of grassland and each one has its own name. Prairies, plains and savannas are all grasslands.

Grasslands develop where there isn't enough rain for forests but too much rain for deserts. Grasslands are filled with - you guessed it - grass. There are many types of grass, though. Fields of wheat are considered grasslands, even though they are often cultivated by people. Grass is special because it grows underneath the ground. During cold periods the grass can stay dormant until it warms up.

The Savanna

A savanna is a rolling grassland scattered with shrubs and isolated trees, which can be found between a tropical rainforest and desert biome. Not enough rain falls on a savanna to support forests. Savannas are also known as tropical grasslands. They are found in a wide band on either side of the equator on the edges of tropical rainforests.

Savannas have warm temperature year round. There are actually two very different seasons in a savanna; a very long dry season (winter), and a very wet season (summer). In the dry season only an average of about 4 inches of rain falls. Between December and February no rain will fall at all. Oddly enough, it is actually a little cooler during this dry season. But don't expect sweater weather; it is still around 70° F.

In the summer there is lots of rain. In Africa the monsoon rains begin in May. An average of 15 to 25 inches of rain falls during this time. It gets hot and very humid during the rainy season. Every day the hot, humid air rises off the ground and collides with cooler air above and turns into rain. In the afternoons on the summer savanna the rains pour down for hours. African savannas have large herds of grazing and browsing hoofed animals. Each animal has a specialized eating habit that reduces compitition for food.

There are several different types of savannas around the world. The savannas we are most familiar with are the East African savannas covered with acacia trees. The Serengeti Plains of Tanzania are some of the most well known. Here animals like lions, zebras, elephants, and giraffes and many types of ungulates(animals with hooves) graze and hunt. Many large grass-eating mammals (herbivores) can survive here because they can move around and eat the plentiful grasses. There are also lots of carnivores (meat eaters) who eat them in turn.

South America also has savannas, but there are very few species that exist only on this savanna. In Brazil, Colombia, and Venezuela, savannas occupy some 2.5 million square kilometers, an area about one-quarter the size of Canada. Animals from the neighboring biomes kind of spill into this savanna. The Llanos of the Orinoco basin of Venezuela and Columbia is flooded annually by the Orinoco River. Plants have adapted to growing for long periods in standing water. The capybara and marsh deer have adapted themselves to a semi-aquatic life.

Brazil's cerrado is an open woodland of short twisted trees. The diversity of animals is very great here, with several plants and animals that don't exist anywhere else on earth.

There is also a savanna in northern Australia. Eucalyptus trees take the place of acacias in the Australian savanna. There are many species of kangaroos in this savanna but not too much diversity of different animals

Plants of the savannas are highly specialized to grow in this environment of long periods of drought. They have long tap roots that can reach the deep water table, thick bark to resist annual fires, trunks that can store water, and leaves that drop of during the winter to conserve water. The grasses have adaptations that discourage animals from grazing on them; some grasses are too sharp or bitter tasting for some animals, but not others, to eat. The side benefit of this is that every species of animal has something to eat. Different species will also eat different parts of the grass. Many grasses grow from the bottom up, so that the growth tissue doesn't get damaged by grazers. Many plants of the savanna also have storage organs like bulbs and corms for making it though the dry season.

Most of the animals on the savanna have long legs or wings to be able to go on long migrations. Many burrow under ground to avoid the heat or raise their young. The savanna is a perfect place for birds of prey like hawks and buzzards. The wide, open plain provides them with a clear view of their prey, hot air updrafts keep them soaring, and there is the occasional tree to rest on or nest in. Animals don't sweat to lose body heat, so they lose it through panting or through large areas of exposed skin, or ears, like those of the elephant.

The savanna has a large range of highly specialized plants and animals. They all depend on the each other to keep the environment in balance. There are over 40 different species of hoofed mammals that live on the savannas of Africa. Up to 16 different species of browsers (those who eat leaves of trees) and grazers can coexist in one area. They do this by having their own food preferences, browsing/grazing at different heights, time of day or year to use a given area, and different places to go during the dry season.

These different herbivores provide a wide range of food for carnivores, like lions, leopards, cheetahs, jackals and hyenas. Each species has its own preference, making it possible to live side by side and not be in competition for food.

In many parts of the savannas of Africa people have started using it to graze their cattle and goats. They don't move around and soon the grasses are completely eaten up. With no vegetation, the savanna turns into a desert. Huge areas of savanna are lost to the Sahara desert every year because of overgrazing and farming.

 

The Steppe

The Steppe  is usually found between the desert and the forest. If it got more rain, it would become a forest. If it got less rain, it would become a desert. The average rainfall is 10-30 inches per year. But in May, June, and August, the Steppe can get up to 4-5 inches a month.

There are many plants in Steppe. The main ones are different grasses. The grasses are separated into 3 different groups, depending on how much rain they get. The tall grasses grow up to 4 1/2 feet because they live closer to the forest. The short grasses can be less than 1 1/2 feet. They are closer to the dessert. 1 1/2 feet is a small amount, considering that people don't cut the grasses. The last group is the mixed grasses. They grow 2-3 feet high and get 15-20 inches of rain per year.

Very few people live in the Steppe climate because it's only grass and it has very few other traits. Farmers would have a hard time growing crops because the soil is so poor and its so cold. There is also a lot of wind in the Steppe because there are few trees.

Steppe has warm summers and really cold winters. There is often a lot of snow in the northern Steppes. All the Steppes experience long droughts and violent winds. Sometimes the summers are so hot that the grasses catch on fire. That is more dangerous than usual because the grass is so dry that it spreads quickly.

A lot of the animals that live in Steppe are grazing animals, such as rabbits, mice, antelopes, horses, etc. Smaller animals have little defense from predators. Since it is such an open environment and predators can find animals fast, they either form herds or make burrows. There are many endangered animals on the Steppe. More and more people are trying to protect them.

A true natural grassland is becoming harder and harder to find because people are taking them over. They are plowing the grass for farming and digging holes in search of oil. The Steppe biome is becoming endangered, just like the animals.

Definition of Biodiversity:
Biodiversity has been most generally defined as the "full variety of life on Earth". More specifically, biodiversity is the study of the processes that create and maintain variation. It is concerned with the variety of individuals within populations, the diversity of species within communities, and the range of ecological roles within ecosystems.

Importance of biodiversity
Environmental problems : Earth functions like a complex system with very complex components that affect each other. Each species -- from the lowliest microbe to humans -- plays a part in keeping the planet running smoothly. In this sense, each part is related. If a lot of those parts suddenly vanish, then the machine that is Earth can't function properly.

For example, the crops that we grow though our clever use of agriculture are enabled by the nitrogen present in the soil. This nitrogen nourishes and strengthens our crops. But where does it come from? Worms, bacteria and other life found within the soil love to decompose vegetation. When they eat, these organisms produce nitrogen as waste. This nitrogen is used to make soil rich.

If we have a small bottle with a group of dominating predators and prey together, soon they will both die out because there is no sustainability. Likewise, if humans manipulate the environment and decrease biodiversity, our environmental sustainability significantly decreases.

Economic Importance of Biodiversity:

• Biologically diverse ecosystems are typically more productive than non-diverse ones because they contain a wider array of resources, and it is impossible for us to use up all of them at once.
• Biodiversity provides many different resources that can be exploited economically, such as fibres wood, fuels, rubber, and silk.
• Many medicines are made from extracts taken from the Amazon rainforest
• Biodiverse environments can often be used as tourist attractions
• The Amazon rainforest is one of the most dominant rubber-producers in the world
• Illegal biological trade exploiting wildlife
• Wood industry
• payments for ecological services rendered by the Amazon such as the carbon retaining in its forests could go a long way to preserving them, a new study has found.


 

Geographic Conditions that Favor Biodiversity

 

According to how geographical natural components are combined, different sceneries are created for the development of species; depending on the combination of features biodiversity is distributed in our planet.

Biodiversity is a result of the evolution of life through millions of years, due to geological processes, as the formation and arrangement of continents, climate changes, ice age, and evolution of species. There are around 30 million of different species in the world. Some of the geographical conditions that favor biodiversity in the world are:

 

Geographic location

The inter tropical zone (between the tropics of Cancer and Capricorn) is the one that as the biggest amount of species because warm stripes due to latitude are good conditions for different species that can adapt to live in high temperatures and lots of humidity.

 

Continentality

Having oceans and seas contributes for a broadest biodiversity in a country. These bodies of water and the ocean currents have influence in climate, which favors diversity of vegetal and animal species.

 

Diversity of Landscape

It is the result of the combination of unique natural components, as well as climates with specific relief and native vegetation.

 

Isolation

The separation of islands and continents, together with specific natural characteristics of a region as well as its relief hydrology, climate and vegetation, has allowed the development of unique species, called endemic, because they can´t be found in any other place on the planet.

 

 

 

 

 

Megadiverse Countries

 

The megadiverse countries are a group of countries that harbor the majority of the Earth's species and are therefore considered extremely biodiverse. Conservation International identified 17 megadiverse countries in 1998.[1][2][3] All are located in, or partially in, the tropics.

 

In 2002, Mexico formed a separate organization focusing on Like-Minded Megadiverse Countries, consisting of countries rich in biological diversity and associated traditional knowledge. This organization does not include all the megadiverse countries as identified by Conservation International.

 

 

 

 

Megadiverse countries

 

In alphabetical order, the 17 countries are:

 

 

  Australia

  Brazil

  China

  Colombia

  Democratic Republic of the Congo

  Ecuador

  India

  Indonesia

  Madagascar

  Malaysia

  Mexico

  Papua New Guinea

  Peru

  Philippines

  South Africa

  United States