Plant Ecology in Context to Desert Biome

Running head: PLANT ECOLOGY RESEARCH 1
Discussion on Plant Ecology in Context to Desert Biome
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Author Note

PLANT ECOLOGY RESEARCH 2
Part 1
Geological and ecological areas based community on a large global scale is known as
a biome. The environmental condition of a biome is determined by several abiotic factors
such as geology, soil type, relief, climate, temperature and vegetation. The primary type of
biomes recognized are grasslands, aquatic, forest and desert. Within the same prefixed
ecological area distribution, several ecosystems can be observed forming a biome. The global
distribution of biomes is determined by the annual measure of two variables, precipitation
and temperature. The biome type can be adjudged by the annual temperature measures based
on the proximity to the equatorial region of the globe, greater the distance, lower the
temperature. Classification of biomes based on a measure of annual precipitation is important
to get an indication of the vegetation level, higher the precipitation, and greater would be the
vegetation. However, desert, a type of terrestrial biome, tends to have extreme levels of both
the variables, that is, high levels of temperature, with very low levels of precipitation. This
tends to the development of few characteristic features of desert including drought, aridity,
extremely low precipitation, low humidity and extremely high temperatures. Such extremities
result in an associated threat of high evaporation rate of water in plants and the absence of
biologically nutrient soil.
A critical process in the plant systems which enables them to produce organic
molecules is photosynthesis. The photosynthetic process helps the plants to harness the solar
radiation from the sun to convert into chemical energy. Sugar is one of the byproducts formed
by further exploitation of this chemical energy. The harnessing of solar radiation is performed
by the photosynthetic system comprising of absorbing pigments and other complexes which
helps in the conversion of solar energy to the chemical. The primary absorbing pigments,
chlorophyll ‘a’ and chlorophyll ‘b’ absorb photons of radiation one at a time, which is
transferred to a single photon receptor chlorophyll a molecule at the reaction center. This

PLANT ECOLOGY RESEARCH 3
photon displaces an electron from the receptor and the void is fulfilled by electron received
from the breaking down of water molecules, leading to the formation of O2 molecules and
[H+] ions. The increasing concentration of hydrogen ions passes through ATP synthase to
form ATP (energy molecule). On the other hand, the free electron passes through several
complexes in the electron transport chain leading to the generation of NADPH energy carrier
molecule. This generated chemical energy is used in the Calvin cycle for the formation of
sugar molecules. In the mesophyll of the cell, RuBisCO enzyme initiates carbon fixation by
hydrolyzing a 6-carbon molecule of 3-phosphoglycerate.
This 6-carbon molecule is reduced in the initial steps of carbon fixation in the Calvin
cycle. The final product formed with the reduction is glyceraldehyde-3-phosphate (G3P),
which is synthesized to starch and sugar, post leaving the Calvin cycle. Completion of three
turns of Calvin cycle results in the formation of one molecule of G3P. This photosynthetic
process is considered important for plant growth. However, the realized efficiency levels of
the process are very low, with the conversion rate of solar to the chemical energy of only 2-
4%. The correlation of photosynthetic rate with the overall plant growth rate is quite
insignificant. The lower efficiency levels of the photosynthetic process are affected by
nutrient and water limitations.
For most of the plant’s metabolic and other biological activity, water plays a crucial
role as it is one of the most significant solvents for biochemical reactants to dissolve.
Carbohydrate synthesis during the photosynthetic process is aided by carbon dioxide and
water. For the movement of nutrients throughout the plant body, water plays the role of the
transport medium. Transpiration is the evaporation process in plants in which the water
absorbed from the roots of a plant are transported through xylem tissues to the leaf surfaces,
from where it is diffused to air via the stomatal opening. In desert biome, where there is
limited availability of water, a significant impact on the overall plant growth is observed,