A tropical climate in the Köppen climate classification it is a non-arid climate in which all twelve months have mean temperatures of at least 18 °C (64 °F). In tropical climates there is often only two seasons, a wet season and a dry season. Tropical climates are frost-free and changes in the solar angle are small. In tropical climates temperature remains relatively constant (hot) throughout the year.
Crops : coconut, rubber, oil palm, cocoa and sugar cane.
TEMPERATE CLIMATE
In geography, temperate or tepid latitudes of Earth lie between the tropics and the polar regions. The temperatures in these regions are generally relatively moderate, rather than extremely hot or cold, and the changes between summer and winter are also usually moderate.
ZONES AND CLIMATES WITHIN THE TEMPERATE ZONE
The north temperate zone extends from the Tropic of Cancer (approximately 23.5° north latitude) to the Arctic Circle (approximately 66.5° north latitude). The south temperate zone extends from the Tropic of Capricorn (approximately 23.5° south latitude) to the Antarctic Circle (at approximately 66.5° south latitude).
In some climate classifications, the temperate zone is often divided into several smaller climate zones, based on latitude. These include Humid subtropical climate, Mediterranean climate, oceanic, and Continental climate.
TUNDRA CLIMATE
In physical geography, tundra is a type of biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра (tûndra) from the Kildin Sami word tūndâr "uplands", "treeless mountain tract". There are three types of tundra: Arctic tundra, alpine tundra, and Antarctic tundra. In tundra, the vegetation is composed of dwarf shrubs, sedges and grasses, mosses, and lichens. Scattered trees grow in some tundra regions. The ecotone (or ecological boundary region) between the tundra and the forest is known as the tree line or timberline.
DESERT
The dry desert is in Köppen's BWh climate category. It is a Low Latitude climate. The Bstands for Dry Desert climates. All months have average temperatures over 64° F (18° C). The Wstands for desert climate. Finally, the hstands for dry and hot, with average annual temperatures over 64° F (18° C). I guess they're trying to tell us its hot, hot out there.
The description of this awesome biome climate is quite odd, but also as it is odd, it is also very interesting.
Dry Desert climates are formed by high-pressure zones in which cold air descends. Then the descending air becomes warm but, instead of releasing rain, the heat from the ground evaporates the water before it can come down as rain. The ground is super hot because the sun's rays beat down on it directly overhead. Not a lot of atmosphere to protect it from radiant energy.
By the way, approximately 1 in. (2.5 cm) of rain falls in dry deserts per year. The average annual temperature of these miles of hot sand is 64° F (18° C).
The latitude range is 15-28° north and south of the equator. Their global range covers about 1/5 of the earth, including the world's great deserts: Sahara, Sonora, Thar, Kalahari and the Great Australian.
Plants of the Dry Desert have adapted to the lack of water by using dew for moisture and taking in water through their leaves and stems.
WATER
Food and agriculture are the largest consumers of water, requiring one hundred times more than we use for personal needs. Up to 70% of the water we take from rivers and groundwater goes into irrigation, about 10% is used in domestic applications and 20% in industry. Currently, about 3600 km³ of freshwater are withdrawn for human use. Of these, roughly half is really consumed as a result of evaporation, incorporation into crops and transpiration from crops. The other half recharges groundwater or surface flows or is lost in unproductive evaporation. Up to 90% of the water withdrawn for domestic use is returned to rivers and aquifers as waste water and industries typically consume only about 5% of the water they withdraw. This waste water from domestic sewage systems and industries should be treated before being dismissed.Farm water, also known as agricultural water is water committed for use in the production of food and fiber.
PEAT SOIL
Peat is a heterogeneous mixture of more or less decomposed plant (humus) material that has accumulated in a water-saturated environment and in the absence of oxygen.
Its structure ranges from more or less decomposed plant remains to a fine amorphic, colloidal mass. The warmer the climate, the quicker the plant material will decompose.
The rate of accumulating plant material is greatest in areas where the temperature is high enough for plant growth but too low for the vigorous microbial activity that breaks down the plant material. Such conditions are found more frequently in the northern hemisphere.
In "Wise Use of Mires and Peatlands" by Donal Clarke and Hans Joosten (2002), the following terms are used:A wetland is an area that is inundated or saturated by water at a frequency and for a duration sufficient to support a prevalence of vegetation typically adapted for life in saturated soil conditions.
Peat is sedentarily accumulated material consisting of at least 30% (dry mass) of dead organic material.A peatland is an area with or without vegetation with a naturally accumulated peat layer at the surface.A mire is a peatland where peat is currently being formed.A suo is a wetland with or without a peat layer dominated by a vegetation that may produce peat.
COASTAL ALLUVIUM SOIL
An alluvial system consists of sediments eroded, transported, and deposited by water flowing in rivers or streams. The sediments, known as alluvium, can range from clay-sized particles less than 0.002 mm in diameter to boulders greater than 64 mm in diameter, depending on their source and the sediment transport capacity of streams in the system. The term alluvial is closely related to the term fluvial, which refers to flowing water. Thus, alluvial systems are the result of fluvial processes.
Modern alluvial systems can create flat and fertile valley bottoms that are attractive for farming because of their rich soils, which are replenished during frequent floods. The same floods that replenish soils, though, can become hazardous when homes are built on floodplains. Ancient alluvial systems that now lie below Earth's surface can be exceptionally good aquifers and petroleum reservoirs.
RAPIDLY WEATHERING SOIL
The process of weathering typically begins when the earth’s crust is uplifted by tectonic forces. After the physical breakup and chemical decay of exposed rocks by weathering, the loosened rock fragments and alterations products are carried away through the process of erosion.
Erosion relies on transporting agents such as wind, rivers, ice, snow and downward movement of materials to carry weathered products away from the source area. As weathered products are carried away, fresh rocks are exposed to further weathering. Over time, that mountain or hill is gradually worn down.
There are two types of weathering:
(a) Chemical Weathering results from chemical reactions between minerals in rocks and external agents like air or water. Oxygen oxidizes minerals to alteration products whereas water can convert minerals to clays or dissolve minerals completely.
(b) Physical Weathering is when rocks are broken apart by mechanical processes such as rock fracturing, freezing and thawing, or breakage during transport by rivers or glaciers.
Factors Which Control the Rates of Weathering
Properties of the Parent Rock
1. The mineralogy and structure of a rock affects it’s susceptibility to weathering.
2. Different minerals weather at different rates. Mafic silicates like olivine and pyroxene tend to weather much faster than felsic minerals like quartz and feldspar. Different minerals show different degrees of solubility in water in that some minerals dissolve much more readily than others. Water dissolves calcite more readily than it does feldspar, so calcite is considered to be more soluble than feldspar.
3. A rock’s structure also affects its susceptibility to weathering. Massive rocks like granite generally to not contain planes of weakness whereas layered sedimentary rocks have bedding planes that can be easily pulled apart and infiltrated by water. Weathering therefore occurs more slowly in granite than in layered sedimentary rocks.
Climate
1. Rainfall and temperature can affect the rate in which rocks weather. High temperatures and greater rainfall increase the rate of chemical weathering.
2. Rocks in tropical regions exposed to abundant rainfall and hot temperatures weather much faster than similar rocks residing in cold, dry regions.
Soil
1. Soils affect the rate in which a rock weathers. Soils retain rainwater so that rocks covered by soil are subjected to chemical reactions with water much longer than rocks not covered by soil. Soils are also host to a variety of vegetation, bacteria and organisms that produce an acidic environment which also promotes chemical weathering.
2. Minerals in a rock buried in soil will therefore break down more rapidly than minerals in a rock that is exposed to air.
Length of Exposure
1. The longer a rock is exposed to the agents of weathering, the greater the degree of alteration, dissolution and physical breakup. Lava flows that are quickly buried by subsequent lava flows are less likely to be weathered than a flow which remains exposed to the elements for long periods of time.
COOL HIGHLAND SOIL
The Highlands form the largest of our geographical regions and probably the most diverse in terms of landscape and soil patterns. The soil pattern in the Highlands is influenced to a large extent by climate, especially temperature and rainfall. Changes in soil type with altitude are quite marked. Many Highland soils are stony and coarse textured: they are also characterised by being wet and acid, with high organic contents. These are properties inherited from the parent materials of the region. A typical soil pattern is podzols and brown forest soils on gentle slopes, with gleys and peats in depressions.A hard brittle layer – known as an indurated horizon – is often found in Highland soils. It usually occurs close to the soil surface (within about 40cm). It is thought to form as a result of freezing and thawing cycles which redistribute the soil material. Indurated horizons can be found in many different soil types. They are important because they can block drainage and also stop plant roots reaching far into the soil. Most Highland soils are very shallow, often due to shallow parent materials. Peat is very common throughout the Highlands.
The Highland soil conditions impose severe restrictions on land use. Steep slopes and wet, peaty surfaces make the use of agricultural machinery difficult. When rainfall is lower – usually in late spring – non-peaty soils can dry out quickly, creating further management problems. In the past, labour-intensive management allowed small patches of good land to be worked fairly easily. Modern developments in intensive agriculture – the trend towards larger fields and machinery, for example – are largely unsuitable here. In general, the land once used for cropping is now under grass. The main land use in the Highlands is rough grazing. Lower ground, in Strathspey for instance, is used for winter grazing and cropping.
Most woodlands in the Highlands are small and patchy – larger areas (both coniferous and deciduous) are usually plantations. Oak and birch woodland are common at lower altitudes, on brown forest soils and podzols. The mix of species varies between the east and the west of the region. Recreation is an important land use in the Highlands and is both indirectly and directly related to soil type. Deerstalking and grouse shooting, for example, are associated with particular moorland habitats which are closely linked to the underlying soils.
In some parts of the Highlands, soil erosion is becoming increasingly significant. Given the vulnerability of the soils, it requires relatively little disturbance to cause damage, particularly on peaty surfaces. The causes of erosion can be complex and varied but overgrazing by sheep or deer is often involved. Recreational pressures from, for example, skiing developments or large numbers of walkers concentrated into small areas, also cause soil erosion.
GLOBAL WARMING
Global Warming is the increase of Earth's average surface temperature due to effect of greenhouse gases, such as carbon dioxide emissions from burning fossil fuels or from deforestation, which trap heat that would otherwise escape from Earth.
Most climate scientists agree the main cause of the current global warming trend is human expansion of the "greenhouse effect"1 — warming that results when the atmosphere traps heat radiating from Earth toward space. Certain gases in the atmosphere block heat from escaping.
Global warming occurs when carbon dioxide (CO2) and other air pollutants and greenhouse gasses collect in the atmosphere and absorb sunlight and solar radiation that have bounced off the earth’s surface. Normally, this radiation would escape into space—but these pollutants, which can last for years to centuries in the atmosphere, trap the heat and cause the planet to get hotter. That's what's known as the greenhouse effect.
In the United States, the burning of fossil fuels to make electricity is the largest source of heat-trapping pollution, producing about two billion tons of CO2 every year. Coal-burning power plants are by far the biggest polluters. The country’s second-largest source of carbon pollution is the transportation sector, which generates about 1.7 billion tons of CO2 emissions a year.
Curbing dangerous climate change requires very deep cuts in emissions, as well as the use of alternatives to fossil fuels worldwide. The good news is that we’ve started a turnaround: CO2 emissions in the United States actually decreased from 2005 to 2014, thanks in part to new, energy-efficient technology and the use of cleaner fuels. And scientists continue to develop new ways to modernize power plants, generate cleaner electricity, and burn less gasoline while we drive. The challenge is to be sure these solutions are put to use and widely adopted.
DESERTIFICATION
Desertification is a type of land degradation in which relatively dry area of land becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife.It is caused by a variety of factors, such as through climate change and through the overexploitation of soil through humankind's undertaking. When deserts appear automatically over the natural course of a planet's life cycle, then it can be called a natural phenomenon; however, when deserts emerge due to the rampant and unchecked depletion of nutrients in soil that are essential for it to remain arable, then a virtual "soil death" can be spoken of, which traces its cause back to human overexploitation. Desertification is a significant global ecological and environmental problem.
Causes of Desertification
· Overgrazing: Animal grazing is a huge problem for many areas that are starting to become desert biomes. If there are too many animals that are overgrazing in certain spots, it makes it difficult for the plants to grow back, which hurts the biome and makes it lose its former green glory.
· Deforestation: When people are looking to move into an area, or they need trees in order to make houses and do other tasks, then they are contributing to the problems related to desertification. Without the plants (especially the trees) around, the rest of the biome cannot thrive.
· Farming Practices: Some farmers do not know how to use the land effectively. They may essentially strip the land of everything that it has before moving on to another plot of land. By stripping the soil of its nutrients, desertification becomes more and more of a reality for the area that is being used for farming.
· Urbanization and other types of land development. As mentioned above, development can cause people to go through and kill the plant life. It can also cause issues with the soil due to chemicals and other things that may harm the ground. As areas become more urbanized, there are less places for plants to grow, thus causing desertification.
· Climate Change: Climate change plays a huge role in desertification. As the days get warmer and periods of drought become more frequent, desertification becomes more and more eminent. Unless climate change is slowed down, huge areas of land will become desert; some of those areas may even become uninhabitable as time goes on.
· Stripping the land of resources. If an area of land has natural resources like natural gas, oil, or minerals, people will come in and mine it or take it out. This usually strips the soil of nutrients, which in turn kills the plant life, which in turn starts the process toward becoming a desert biome as time goes on.
· Natural Disasters: There are some cases where the land gets damaged because of natural disasters, including drought. In those cases, there isn’t a lot that people can do except work to try and help rehabilitate the land after it has already been damaged by nature.
EFFECTS OF DESERTIFICATION
· Farming becomes next to impossible. If an area becomes a desert, then it’s almost impossible to grow substantial crops there without special technologies. This can cost a lot of money to try and do, so many farmers will have to sell their land and leave the desert areas.
· Hunger: Without farms in these areas, the food that those farms produce will become much scarcer, and the people who live in those local areas will be a lot more likely to try and deal with hunger problems. Animals will also go hungry, which will cause even more of a food shortage.
· Flooding: Without the plant life in an area, flooding is a lot more eminent. Not all deserts are dry; those that are wet could experience a lot of flooding because there is nothing to stop the water from gathering and going all over the place. Flooding can also negatively affect the water supply, which we will discuss next.
· Poor Water Quality: If an area becomes a desert, the water quality is going to become a lot worse than it would have been otherwise. This is because the plant life plays a significant role in keeping the water clean and clear; without its presence, it becomes a lot more difficult for you to be able to do that.
· Overpopulation: When areas start to become desert, animals and people will go to other areas where they can actually thrive. This causes crowding and overpopulation, which will, in the long run, end up continuing the cycle of desertification that started this whole thing anyway.
· Poverty: All of the issues that we’ve talked about above (related to the problem of desertification) can lead to poverty if it is not kept in check. Without food and water, it becomes harder for people to thrive, and they take a lot of time to try and get the things that they need.
SOLUTIONS FOR DESERTIFICATION
· Policy Changes Related to How People can Farm. In countries where policy change will actually be enforced on those in the country, policy change related to how often people can farm and how much they can farm on certain areas could be put into place to help reduce the problems that are often associated with farming and desertification.
· Policy Changes to Other Types of Land Use. If people are using land to get natural resources or they are developing it for people to live on, then the policies that govern them should be ones that will help the land to thrive instead of allowing them to harm the land further. The policy changes could be sweeping or they could be depending on the type of land use at hand.
· Education: In developing countries, education is an incredibly important tool that needs to be utilized in order to help people to understand the best way to use the land that they are farming on. By educating them on sustainable practices, more land will be saved from becoming desert.
· Technology Advances. In some cases, it’s difficult to try and prevent desertification from happening. In those cases, there needs to be research and advancements in technology that push the limits of what we currently know. Advancements could help us find more ways to prevent the issue from becoming epidemic.
· Putting Together Rehabilitation Efforts. There are some ways that we can go back and rehabilitate the land that we’ve already pushed into desertification; it just takes some investment of time and money. By putting these together, we can prevent the issue from becoming even more widespread in the areas that have already been affected.
· Sustainable practices to prevent desertification from happening. There are plenty of sustainable practices that can be applied to those acts that may be causing desertification. By adding these to what we should be doing with land, we can ensure that we don’t turn the entire world into a desert.
Eutrophication or more precisely hypertrophication, is the enrichment a water body with nutrients, usually with an excess amount of nutrients. This process induces growth of plants and algae and due to the biomass load, it may result in an oxygen depletion. One example is the "bloom" or great increase of phytoplankton in a water body as a response to increased levels of nutrients. Eutrophication is almost always induced by the discharge of phosphate-containing detergents, fertilizers, or sewage, into an aquatic system.
MECHANISM OF EUTROPHICATION
EUTROPHICATION ARISES FROM THE OVERSUPPLY OF NUTRIENTS, WHICH LEADS TO OVER GROWTH OF PLANTS AND ALGAE. AFTER SUCH ORGANISMS DIE, THE BACTERIAL DEGRADATION OF THEIR BIOMASS CONSUMES THE OXYGEN IN THE WATER, THEREBY CREATING THE STATE OF HYPOXIA.
According to Ullmann's Encyclopedia, "the primary limiting factor for eutrophication is phosphate." The availability of phosphorus generally promotes excessive plant growth and decay, favouring simple algae and plankton over other more complicated plants, and causes a severe reduction in water quality. Phosphorus is a necessary nutrient for plants to live, and is the limiting factor for plant growth in many freshwater ecosystems. Phosphate adheres tightly to soil, so it is mainly transported by erosion. Once translocated to lakes, the extraction of phosphate into water is slow, hence the difficulty of reversing the effects of eutrophication.
The sources of these excess phosphates are detergents, industrial/domestic run-offs, and fertilizers. With the phasing out of phosphate-containing detergents in the 1970s, industrial/domestic run-off and agriculture have emerged as the dominant contributors to eutrophication.
Lakes and rivers
When algae die, they decompose and the nutrients contained in that organic matter are converted into inorganic form by microorganisms. This decomposition process consumes oxygen, which reduces the concentration of dissolved oxygen. The depleted oxygen levels in turn may lead to fish kills and a range of other effects reducing biodiversity. Nutrients may become concentrated in an anoxic zone and may only be made available again during autumn turn-over or in conditions of turbulent flow.
Enhanced growth of aquatic vegetation or phytoplankton and algal blooms disrupts normal functioning of the ecosystem, causing a variety of problems such as a lack of oxygen needed for fish and shellfish to survive. The water becomes cloudy, typically coloured a shade of green, yellow, brown, or red. Eutrophication also decreases the value of rivers, lakes and aesthetic enjoyment. Health problems can occur where eutrophic conditions interfere with drinking water treatment.
Human activities can accelerate the rate at which nutrients enter ecosystems. Runoff from agriculture and development, pollution from septic systems and sewers, sewage sludge spreading, and other human-related activities increase the flow of both inorganic nutrients and organic substances into ecosystems. Elevated levels of atmospheric compounds of nitrogen can increase nitrogen availability. Phosphorus is often regarded as the main culprit in cases of eutrophication in lakes subjected to "point source" pollution from sewage pipes. The concentration of algae and the trophic state of lakes correspond well to phosphorus levels in water. Studies conducted in the Experimental Lakes Area in Ontario have shown a relationship between the addition of phosphorus and the rate of eutrophication. Humankind has increased the rate of phosphorus cycling on Earth by four times, mainly due to agricultural fertilizer production and application. Between 1950 and 1995, an estimated 600,000,000 tonnes of phosphorus was applied to Earth's surface, primarily on croplands. Policy changes to control point sources of phosphorus have resulted in rapid control of eutrophication.
Natural eutrophication
Although eutrophication is commonly caused by human activities, it can also be a natural process, particularly in lakes. Eutrophy occurs in many lakes in temperate grasslands, for instance. Paleolimnologists now recognise that climate change, geology, and other external influences are critical in regulating the natural productivity of lakes. Some lakes also demonstrate the reverse process (meiotrophication), becoming less nutrient rich with time. The main difference between natural and anthropogenic eutrophication is that the natural process is very slow, occurring on geological time scales.
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