Kingdom Plantae

Kingdom Plantae contains nearly 300,000 different kinds of plants. They also place the macroscopic, multicellular brown algae (Division Phaeophyta) and red algae (Division Rhodophyta) in the Kingdom Plantae.Although this does not make it the largest kingdom, many might argue that it is the most important one.In the process known as "photosynthesis ", plants use the energy of the Sun to make food and oxygen. This complex chemical reaction provides nearly all the oxygen in Earth's atmosphere and all the food required by living things. Although some protists and bacteria are capable of performing photosynthesis, plants do most of the photosynthesis on Earth.

                 The ancestors of plants first appeared in the seas nearly 700 million years ago. Another 265 million years passed before the first plants appeared on land. These early land plants looked very different than the plants you're familiar with today. In fact, many of them didn't even have roots, stems, or leaves! Since then, plants have taken on a variety of forms and are found in most places on Earth.

General Characteristics
 

A. Contain chlorophylls a and b.
B. Cell walls made of cellulose.
C. Have tissues and organs (roots, stems and leaves).
 

 Evolution of Plants
A. Evidence that plants evolved from algae
1. Green algae and plants both have chloroplast with chlorophylls a and b
2. Both have cell walls made of cellulose.
3. Both form starch as stored glucose.
4. Both demonstrate alternation of generations

Problems with life on land
A. Dehydration
1. Adaptations
a) Roots, vascular tissue, cuticles and bark
B. Support
1. Adaptations
a) Stiffer, thick cell walls; wood
C. Distribution of gametes and/or spores
1. Adaptations
a) Water tight seeds and/or spores.
b) Spores lighter than air.

Classification of Plants

A. Phylum Bryophyta 

• Primitive
• Lack vascular tissue
• Lack true roots
• Mosses and liverworts (Hepatophyta)

B. Super Phylum Tracheophyta

• More advanced than Bryophytes
• Contain vascular tissue

C. Phylum Pterophyta 

• Reproduce by spores
• Leaves generally grow from underground stems
• Ferns and horse tails

D. Phylum Coniferophyta

• Produce naked seeds in cones
• Many are evergreens
• Produce soft wood
• Needle like leaves
• Redwoods, pines, cypress and junipers

E. Phylum Anthophyta

• Flowering plants
• Either herbaceous or hardwoods
• Most advanced of all plant forms

a) Class Monocotyldonae (Monocots)

• Seeds contain one cotyledon
• Leaves have parallel veins
• Flower parts are usually in multiples of 3
• Lack cambium
• In the stem, vascular bundles are scattered
• Generally wind pollinated
• All are herbaceous with a few exceptions

b) Class Dicotyledonae (Dicots)

• This class is now called Eudicotyledonae
• Seeds contain two cotyledons
• Leaves have netted veins
• Flower parts are usually in multiples of 4 or 5
• Have cambium
• Vascular bundles are arranged in a cylinder, in the stem.
• Generally pollinated by animals.

 Five kingdom classification

Tundra

Tundra Biome

              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.

Characteristics of tundra include:

1. Extremely cold climate


2. Low biotic diversity


3. Simple vegetation structure


4. Limitation of drainage


5. Short season of growth and reproduction


6. Energy and nutrients in the form of dead organic material


7. Large population oscillations

Tundra is separated into two types:

Arctic tundra

                    Arctic tundra is located in the northern hemisphere, encircling the north pole and extending south to the coniferous forests of the taiga. The arctic is known for its cold, desert-like conditions. The growing season ranges from 50 to 60 days. The average winter temperature is -34° C (-30° F), but the average summer temperature is 3-12° C (37-54° F) which enables this biome to sustain life. Rainfall may vary in different regions of the arctic. Yearly precipitation, including melting snow, is 15 to 25 cm (6 to 10 inches). Soil is formed slowly. A layer of permanently frozen subsoil called permafrost exists, consisting mostly of gravel and finer material. When water saturates the upper surface, bogs and ponds may form, providing moisture for plants. There are no deep root systems in the vegetation of the arctic tundra, however, there are still a wide variety of plants that are able to resist the cold climate. There are about 1,700 kinds of plants in the arctic and subarctic, and these include:

• low shrubs, sedges, reindeer mosses, liverworts, and grasses


• 400 varieties of flowers


• crustose and folios lichen

                   All of the plants are adapted to sweeping winds and disturbances of the soil. Plants are short and group together to resist the cold temperatures and are protected by the snow during the winter. They can carry out photosynthesis at low temperatures and low light intensities. The growing seasons are short and most plants reproduce by budding and division rather than sexually by flowering. The fauna in the arctic is also diverse:

• Herbivorous mammals: lemmings, voles, caribou


• Carnivorous mammals: arctic foxes, wolves, and polar bears


• Migratory birds: ravens, snow buntings, falcons, loons,


• Insects: mosquitoes, flies, moths, grasshoppers


• Fish: cod, flatfish, salmon, and trout

                  Animals are adapted to handle long, cold winters and to breed and raise young quickly in the summer. Animals such as mammals and birds also have additional insulation from fat. Many animals hibernate during the winter because food is not abundant. Another alternative is to migrate south in the winter, like birds do. Reptiles and amphibians are few or absent because of the extremely cold temperatures. Because of constant immigration and emigration, the population continually oscillates.

Alpine tundra
   
                           Alpine tundra is located on mountains throughout the world at high altitude where trees cannot grow. The growing season is approximately 180 days. The nighttime temperature is usually below freezing. Unlike the arctic tundra, the soil in the alpine is well drained. The plants are very similar to those of the arctic ones and include:

• tussock grasses, dwarf trees, small-leafed shrubs, and heaths

Animals living in the alpine tundra are also well adapted:

• Mammals: pikas,, mountain goats, sheep


• Birds: grouse like birds


• Insects: spring tails, grasshoppers ,beetles

world biomes

Grassland biome

TROPICAL GRASSLANDS

           Tropical grasslands, or savannas, are also the homes of primates in Africa and Asia; no savanna-living primates exist in South America. Tropical grasslands comprise a mixture of trees and grasses, the proportion of trees to grass varying directly with the rainfall. Areas of high seasonal rainfall support single-story woodlands of tall trees, while lush grasses form the ground vegetation.

           Tropical grasslands, or savannas, lie north and south of tropical rain forests that are on the equator. Some areas beyond savannas are hot deserts. Other savannas may be lined with mountains, dense forests, and seas. South America is home to several large savannas. An example of one of these savannas is the llanos, which means plains, located in the Orinoco River basin. The llanos is north of the Amazon forests and is shared in areas of Columbia and Venezuela. It is the size of France or Texas. Another large tropical grassland can be found south of the Amazon forest in the Brazilian Highlands, called campos. Other South American grasslands can be found in southeast Venezuela and southern Guyana.

          The worlds largest savannas can be found in Africa. The savanna takes up almost half of the continent. It stretches from the Atlantic coast of West Africa to the east across Sudan, and then goes south through east Africa. From Mozambique the savanna heads west and goes through Zambia and Angola, back to the Atlantic Ocean (Lambert, 30). Other savannas can be found in India's great Deccan Plateau, and in Australia, north of central deserts.

TEMPERATE GRASSLANDS

         The temperate grasslands are located in the mid-latitudes on planet Earth. These include the Prairies of North America, Pampas of South America and the Steppes of Eurasia. The temperate grasslands are further divided on the basis of their general characteristics. The best example of this is the Prairie biome of North America. In semi-arid regions - which are typically characterized by growth of short grass, the Prairies are known as Short-grass Prairies, while the same in regions with high rainfall - typically characterized by growth of tall grass, they are known as Tall-grass Prairies. This is just one of the numerous lesser known attributes of this grassland biome.

         Temperate grasslands are a division of a larger biome grouping of grasslands that includes tropical savannas.  Both biome types are characterized by a dominance of grasses, yet temperate grasslands differ significantly from savannas.  First unlike savannas that can have trees and shrubs scattered throughout, temperate grasslands have trees and shrubs absent.  Temperate grasslands are also found in less tropical ecosystems and thus have a larger temperate fluctuation during the year.  Temperatures in temperate grasslands can vary tremendously which has a large impact on growing seasons.  Generally they also have less rainfall. 

Regional Expressions: Temperate Grasslands are found throughout the globe, generally in the interiors of the continents and north or south of the tropic of cancer/Capricorn.  The following are the major regional expressions of grasslands recognized around the globe.

• Veldts of South Africa
• Puszta of Hungary
• Pampas of Argentina/Uruguay
• Steppes of Russia / China
• Plains and Prairies of North America

Minor Expressions: There are smaller local expressions of grasslands as well.  These include the following:

• Australian Outback
• Minnesota Cedar Creek Region

       Biodiversity: Grasslands (temperate) are dominated by one or a few species of grasses while there are several hundred other types of grasses and non-woody flowering plants that while less abundant make up a vital part of the species composition. There are many types of grass species that are dominant species in their own region.  Each species of grass grows better with varying temperatures / rainfall / and soil conditions.  Grasses are dominant (instead of trees) because of fire, drought and grazing by large herbivores. 

       Drought: Drought plays a large role in keeping trees from taking over the grasslands.  Some years receive less rain than others, just as certain seasons receive significantly less rain than others.  Trees generally can not stand the lack of water as easily as grasses and thus grasses remain dominant.

       Fire: Fire plays a big role in this biome, preserving biodiversity and keeping trees from overtaking the grasses.  Lightning from large storms rolling over the grasslands ignites large grass-fires.  These fires help certain plants by germinating seeds, clearing ground cover to allow rare plants a chance and by nourishing the soil with freshly burnt vegetation.

         Soil: The soil of the temperate grasslands is deep and dark.  The upper layers are the most fertile because of the buildup of many layers of dead branching stems and roots.  This organic mater on the surface and in the dead roots provide a great degree of nourishment for the living plants.

         Rainfall: Rainfall is generally less in temperate grasslands than in tropical savannas, although drought usually plays less of a roll effecting biodiversity than it does in savannas.  Rain usually falls in temperate grasslands in the late spring and early summer.  There is an average of 20 – 35 inches of rainfall a year.  The amount of rainfall however determines the height of grasses in the grassland.  For north America, this rainfall gradient helps to divide the temperate grasslands into tall grass prairies (in wetter areas) and short grass steppes (in dryer habitats).

         Environmental concerns: There is a great concern for remaining grasslands in temperate regions.  Because the soil in these areas is incredibly rich and the land is flat and treeless, most of this biome has been turned into farms or ranches.  The result of this overuse and consumption of the grassland by agricultural practices is a fragmentation of once large tracks of grassland.  Fragmentation decreases biodiversity (Theory of Island Biogeography).  Plowing of grasslands, combined with wind has lead to huge dust storms, such as those which created the Great Dust Bowl in the American Depression of the mid 1920s.  Finally, in dryer areas, overgrazing and salt build-up from irrigation of the land have turned these areas into near-wastelands.

          Floral Diversity: The most common grasses include blue gamma grass, buffalo grass, Johnson grass, and various sorts of wheat and burley.  Common flowers include types of asters, coneflowers, Solidagos (goldenrods), vetches, Indian blankets and sweet clovers.

          Fauna Diversity: In North America common animals include: bison, pronghorns, deer, mice, rabbits, grouse, badgers, skunks, meadowlarks, various  owls, garter snakes, rattle-snakes, red-tailed hawks and prairie dogs. 

Major biomes

Savanna ecosystem

Savanna ecosystem

                A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses. Some classification systems also recognize a grassland savanna from which trees are absent.This article deals only with savanna under the common definition of a grassy woodland with a significant woody plant component.

          It is often believed that savannas feature widely spaced, scattered trees. However, in many savannas, tree densities are higher and trees are more regularly spaced than in forest. Savannas are also characterized by seasonal water availability, with the majority of rainfall confined to one season. Savannas are associated with several types of biomes. Savannas are frequently in a transitional zone between forest and desert or prairie. Savanna covers approximately 20% of the earth's land area.

         Many grassy landscapes and mixed communities of trees, shrubs, and grasses were described as savanna before the middle of the 19th century, when the concept of a tropical savanna climate became established. The Köppen climate classification system was strongly influenced by effects of temperature and precipitation upon tree growth, and his over-simplified assumptions resulted in a tropical savanna classification concept which resulted in it being considered as a "climatic climax" formation. The common usage meaning to describe vegetation now conflicts with a simplified yet widespread climatic concept meaning. The divergence has sometimes caused areas such as extensive savannas north and south of the Congo and Amazon Rivers to be excluded from mapped savanna categories.

         "Barrens" has been used almost interchangeably with savanna in different parts of North America. Sometimes Midwestern savanna were described as "grassland with trees". Different authors have defined the lower limits of savanna tree coverage as 5-10% and upper limits range from 25-80% of an area.

   

       Two factors common to all savanna environments are rainfall variations from year to year, and dry season wildfires. Savannas around the world are also dominated by tropical grasses which use the C4 type of photosynthesis.In the Americas, e.g. in Belize, Central America, savanna vegetation is similar from Mexico to South America and to the Caribbean. In North America nearby trees are of subtropical types, ranging from southwestern Pinyon pine to southeastern Long leaf Pine and northern chestnut oak.

Savanna ecoregions

Savanna ecoregions are of several different types:-

• Tropical and subtropical savannas are classified with tropical and subtropical grasslands and shrub lands as the tropical and subtropical grasslands, savannas, and shrub lands biome. The savannas of Africa, including the Serengeti, famous for its wildlife, are typical of this type.
• Temperate savannas are mid-latitude savannas with wetter summers and drier winters. They are classified with temperate savannas and shrub lands as the temperate grasslands, savannas, and shrub lands biome, that for example cover much of the Great Plains of the United States. (See areas such as the Central forest-grasslands transition).
• Mediterranean savannas are mid-latitude savannas in Mediterranean climate regions, with mild, rainy winters and hot, dry summers, part of the Mediterranean forests, woodlands, and scrub biome. The oak tree savannas of California, part of the California chaparral and woodlands ecoregion, fall into this category.
• Flooded savannas are savannas that are flooded seasonally or year-round. They are classified with flooded savannas as the flooded grasslands and savannas biome, which occurs mostly in the tropics and subtropics.

• Mountain savannas are high-altitude savannas, located in a few spots around the world's high mountain regions, part of the mountain grasslands and shrub lands biome. The highland savannas of the Angolan Scarp savanna and woodlands ecoregion are an example.

Our ecosystem