Māris kļaviņŠ, azamat azizov, JĀnis zaļoksnis environment, pollution, development: the case of uzbekistan

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4. HUMANS AND THE ENVIRONMENT
 4.1. 
 Systems of the Earth: the lithosphere, 
hydrosphere, atmosphere and biosphere
 4.1.1.   Environmental science – a science of environmental 
systems
Everything  is  interrelated.  All  elements  and  processes  in  both 
organic and inorganic nature are interrelated – they influence each 
other in myriads of ways. However, among these innumerable inter-
connections, there are groups of individual elements or processes 
that can be marked out as more closely related, for example, clock-
work parts, computer microchip components or members of one 
family. Each of these aggregates of elements has specific functions: 
clock shows time, computer processes information, family raises new 
members of society.
An aggregate of interconnected elements that performs specific 
functions is called a system (from the Greek word systema, which 
means ‘a whole consisting of parts’). System theory classifies systems 
by their level of complexity. The natural systems comprising the 
Earth and everything on it are extremely complicated systems.
The Sun and its planets formed from the condensation of gas and 
dust clouds in the interstellar space about 4.6 billion years ago. The 
Earth functions by means of specific systems (spheres) – the atmo-
sphere, hydrosphere and litho sphere – and the flows of substances 
and  energy  among  these  systems.  The  spheres  of  the  Earth  differ 
with respect to their composition, mass and processes taking place 
in them (Table 4.1), i.e. the processes of exchange of substances 
composing each sphere (e.g., water evaporation, condensation and 
runoff cycle) (Table 4.2). 
Systems  can  be  open  or  closed.  In  an  open  system,  the  flows 
of  substances  and  energy  are  not  confined.  Ocean  is  an  open 
system  with  respect  to  the  Earth’s  combined  mass  of  water  –  the 
hydrosphere. The Earth, on the one hand, can be considered a 
closed  system  with  respect  to  the  flows  of  substances  (the  Earth’s 
mass is increased by a relatively small mass of falling meteorites, 
and a relatively small mass of substances leaves the upper layers 
of the atmo sphere and dissipates into outer space); on the other