SUBTROPIC AND TROPIC CLIMATIC ZONE

Biogeochemical cycling of elements and pollutants exposure pathways in the tropical ecosystems, which occur between 30°N and 30°S, are both intensive and at high probability of risk for human and ecosystem health. The tropical belt receives about 60% of solar radiation inputting on the Earth s surface. The total area of tropical ecosystems is about 40 x 106 km2, with exception of the High Mountain and Extra-Dry Sandy Deserts with strongly depressed life processes. 

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BIOGEOCHEMICAL CYCLING OF ELEMENTS AND POLLUTANTS EXPOSURE IN SUBTROPIC AND TROPIC CLIMATIC ZONE... 

Shallow water, carbonate-rich sediments are largely confined today to the subtropic and tropic climatic zones, but are found even at high latitudes. Their... 

Other lichens exhibit impressive disjunctions between the southern and northern hemisphere ( bipolar distribution, Galloway and Aptroot, 1995). Some species showing circum-bipolar disjunctions are completely absent in the tropics examples include Parmeliopsis ambigua and Verrucaria maura (Litterski, 1999). Others are additionally found in tropical montane and subalpine areas (Litterski, 1999), and are then often widespread in the cool and temperate zones of the northern and southern hemisphere. In subtropical and tropical climates, these species only occur in higher altitudes, corresponding to montane and subalpine zones e.g. Cladonia rangiferina (Litterski, 1999). 

The different types of insecticide formulations used in the USA and Japan are considered to be attributed to the differences in climate and house construction style. That is to say, mosquito coils are suitable to prevent mosquitoes from entering a house from outside in Japan where the weather is hot and humid in summer and the houses are of an open style. These conditions are similar in subtropical and tropical zones, including south-east Asia. 

On a global scale, arable lands occupy 12% of the terrestrial ecosystems, and pastures occupy 25%. On the whole, the agrolandscapes occupy 40% of the Earth s land. At present the most used areas are in the moderate climate zone (25%) and subtropical and tropical ones (18%). To the maximal extent, natural landscapes and their relevant biogeochemical cycles are transformed into agrogeochemical provinces with a predominance of agrogeochemical cycles of many elements in Europe (>30%) and Asia (>20%). 

The reader can easily estimate whether or not the local conditions in his/her region are suitable for photochemical smog formation. We recall Section 2 that describes the modem state of urban air pollution and the known climatic conditions of subtropical and tropical zone where most Asian mega-cities are located. 

In a warm and semi-arid climate thick calcretes can develop. Alteration in the vadose zone is relatively rapid but not as rapid as in the phreatic zone. Surface karst is present locally, and caves are small and rare. The mineralogical changes follow the pattern of Figure 7.25, but at a rate slower than that for a warm, subtropical climate like Bermuda. Under the extreme of a warm, wet tropical climate, extensive terra-rossa soils can develop, and dissolution features, such as caves, solution pipes and fractures, should be prevalent. Mineralogical stabilization should occur rapidly. 

Starch can be obtained in a great variety of crops, the choice of the botanical resource depending mainly on geographic and climatic factors and on the desired functional properties of the extracted starch [5]. It is always possible to find a highly productive plant to produce starch whatever the climate and agricultural conditions, such as maize in temperate and subtropical zones, cassava (the same as manioc or tapioca) in tropical regions, rice in inundated areas, and wheat or potatoes in temperate and cold climates. The main plant sources are maize, rice, wheat, potatoes and cassava [6]. In the year 2005, worldwide starch production accounted for approximately 58 million tons. 

The results confirm the hypothesis that the Chiquitano dry forest is a transition zone between the humid tropics and sani-arid subtropics and the distribution of species is related to climatic variables which are highly correlated with latitude. The species found in the chiquitano dry forest do not... 

The cathodic current density is a complex ftmction of various seawater parameters, for which no complete model is available. For design purposes, four climatic zones based on average water temperature and two depth ranges have therefore been defined tropical, subtropical, temperate, and arctic. For example, in colder waters current densities tend to be higher due to a lower degree of surface protection from calcareous layers. 

Antipow-Karatajew and Tsyurupa [1964], reviewing the results of Russian investigations on the composition of clay fractions of soils derived from igneous rocks in the different climatic zones of the USSR and parts of South East Asia, pointed out that hydrous mica predominates in almost all soils investigated, except in soils from humid subtropical or tropical zones. 

Leprosy, also referred to as Hansen s disease, is caused by the bacterium Mycobacterium leprae. Although rare in colder climates, this disease may be seen in tropical and subtropical zones. Dapsone and clofazimine (Lamprene) are the two drags currently used to treat leprosy. The leprostatic drugs are listed in the Summaiy Drug Table Leprostatic Dragp. 

Only the northernmost pan of Australia (Cape York, Kimberley and the Arnhem Land peninsula) falls in the belt of equatorial monsoons. It is characterized by Tropical Rain Forest, Afforested Savanna and Light Forest ecosystems on Ferrasols and Nitosols, at places, lateritized soils. The sonthern fringe of the continent, its southwestern and sonlheastem parts, and also the island of Tasmania fall in the subtropical zone in the belt of westerly cyclonic cnrrents of air masses. They experience winter in the Sonthern Hemisphere. A dry snmmer and winter rains impart the characteristics of a Mediterranean snbtropical climate and determine the appearance of Dry Forest and Brnsh ecosystems on different Cambisols. 

The Celastraceae family is probably related phylogenetically with the Aquifoliaceae the presence of glandular discs around the ovary and the bright coloured aril in the Celastraceae are the principal differences between the two families. The Celastraceae family is pantropically distributed with radiation towards temperate or temperate-cold climates. In other words, the Celastraceae are principally concentrated in the tropical and subtropical regions and to a lesser extent in the temperate zones of the world (Figure la). The family is better represented in Central America and the West Indies than m South America except for the Maytenus genus [5] (15 species in Peru and 15 in Venezuela). 

Many countries located in the temperate zone have turned an envious eye to the tropics as a source of additional food resources. Because of improved transportation and preservation techniques, direct imports are a very convenient procedure for obtaining these food items. A second procedure that has been successfully implemented in a few cases is the transplantation of tropical plants for cultivation in northern regions with subtropical conditions such as Southern California and Florida. The banana and coconut are examples of fruits that have been exploited on a large scale. The avocado is gaining greater recognition as a food crop for export and the plant itself is being introduced into areas with more temperate climates. 

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