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It is apparent that global warming, from which all natures suffer, has just pressed and is increasing in alarming rate. This review, thus, aimed at dealing with the consequences of increment of atmospheric temperature on soil physicochemical, biological and morphological responses. The review revealed that soil shares the detrimental effects of global warming in a way that there is direct relationship between atmospheric temperature and soil temperature. Hence, any change on atmospheric temperature as a result of global warming affects soil organisms. Similarly, soil structure, porosity, infiltration and moisture content, are destroyed by the absence of microbes and due to intensive rain drops. Besides, soil biochemical reaction terminates beyond its optimum temperature rage. Global warming, as a result, entirely disrupts soil functions, which calls for mitigation and adaptation schemes.
Global warming is an increase in earth’s annually averaged air temperature near the surface . Recent scientific evidence shows that release of greenhouse to the atmosphere and posing the earth’s temperature called global warming. Carbon dioxide (CO2) is among greenhouse gases that traps temperature and cause the atmosphere warm beyond optimum level (International panel on climate change .
IPCC (1996) projected that in 2050s, the temperature increment will be 2.4 0C and 2.0 0C for the lower and highest scenarios respectively whereas, in 2080s the maximum temperature will be increased by 3.8 0C and 3.2 0C. The ranges of these estimates arise from the use of models with differing sensitivity to greenhouse gas concentrations. Likewise, Yakob  reported that maximum temperature was projected to 1.2 oC in 2020s on Anjeni Watershed in Blue Nile basin in Ethiopia.
Natural resource, on which entire lives on the earth depend, is the vulnerable resource that receives the detrimental effects of this climate change, which in turn brings ecological disturbances (www.environment.about.com/od/effectonnaturalresources ). Hence soil is the end product of the influence of the climate, relief, organisms, parent materials and time , any change manifested on these factors can indirectly affect the composition and properties of the soil.
According to Field et al.  finding, changes in soil moisture and soil temperature influence ecosystem processes viz-a-viz nutrient cycling, primary productivity, plant survival and recruitment in terrestrial ecosystems. Soil aggregate-destruction by raindrops, surface runoff and filtrating water, and changes in the vegetation pattern and land use practices are also the consequences of climate change (Várallyay, 2010).
Soil bio-physicochemical properties are therefore highly influenced by soil moisture (Brinkman and Sombroek, 1993). Besides, Delgado et al.  reported that there is a close relationship between climate change, limited global water and soil resources, population growth, and food security. As climate change impacts the world’s soil and water resources, it threatens food production and/or food production potential. As impaired ecosystem, soil cannot normally function to support and provide good and services . Thus, the objective of this paper was to review the correlation between air and soil temperature and then soil physicochemical, biological and morphological responses to global warming.
The response of soil temperatures to changes in air temperature strongly depends on the temporal distribution, depth, and density of the snowpack during the winter . Fluctuation of air temperature attributes to small changes in the size of CO2 flux. The soil CO2 emission fluxes thereon increased 86.86% with the air temperature increasing 3.74°C . As Hunt et al.  demonstrated on 3 sites in different region across USA, there were strong relationships between the average daily air temperatures and observed daily soil temperatures at the 10cm depth for all 7 model development sites; R2 values ranged from 0.86 to 0.97.
Ahmad & Rasul  have also modeled proportional the
relationship between air temperature and soil temperature in
Pakistan. They also depicted that there was significant, greater
than 85%, positive correlation between soil and air temperature
in all scenarios (Figure 1). According to Hunt et al. (1993) ,
in Montana region, one unit increase in air temperature will
increase soil temperature by 4.87 units.
There great diversity of soil organisms many of which have
similar functions and general decomposition function, are
disrupted by climate change . Increased microbial activity
due to optimum temperature produces greater amounts of
polysaccharides and other soil stabilizers. However, these
microorganisms’ population, structure and composition are
inhibited by the anticipated extreme temperature. (Brinkman
and Sombroek, 1993).
Adverse environmental conditions, mainly elevated soil
temperature is likely to facilitate fungi to survive better, since
they rely on more aerobic conditions . Moreover, filamentous
nature and lower N content of fungi  makes the tolerant to
higher soil temperature and drying . Thus, beyond certain
threshold warming may enhance fungal contribution to the
microbial community .
The effects of increased atmospheric CO2 concentration on
bacterial biomass, richness, and community composition have
been shown to vary between ecosystems, resulting in no common
trends, except a 3.5fold decrease in the relative abundance
of Acidobacteria group 1 bacteria . As a result, increased
temperature often affects recalcitrant soil organic matter more
than labile soil organic matter , which attributes to increased
warming of passing the critical activation energy (Ea) needed for
decomposing resistant compounds .
Additionally, long-term warming could also induce changes
in plant species composition, which can significantly affect
soil microbial production of extracellular enzyme activity.
Changes in extracellular enzyme activities and production may
influence which compounds are most effectively utilized by
soil microorganisms under warming conditions and potentially result in altered nutrient pools . These intermingling effects
eventually result in disruption of soil microbial structure,
biomass and function (Figure 2).
According to Schimel & Gulledge , populations of
cellulolytic and ligninolytic fungi reduction may impose a
decrease in litter decomposition greater than would be predicted
by considering only the changes in soil and litter moisture in
areas where episodic drying and rewetting of soil attributed to
climate change becomes more severe.
Even though it accelerates soil chemical reaction, soil
temperature impairs soil chemical composition and/or soil
fertility at its level . Climate change can also influence acid
sulphate soils production via sea level rise and via changes to
rainfall incidence and flood flows. Therefore, pH values may
temporarily reach 2.5 to 3.5 and a small part of the clay fraction
may be decomposed as indicated under processes in soils, above.
This then buffers the pH generally between 3.5 and 4 in the long
Fluctuation of temperature increase freeze-thaw cycle,
which result increase in exchangeable NH4-N and decreased
exchangeable K. This creates movement of water along with
gradients of nutrients and thermal conductivity and effects
nutrient availability, cation exchange properties, soil weathering,
and biological activity . Enhanced in soil water movement
leads to active and increased groundwater discharge and further
depletes soil nutrients .
Moreover, Groffman et al. (2001) depicted that if ongoing
global warming continues, freeze-thaw cycles in highland soils
can significantly influence the availability of Zn, after freezethaw
cycles, the highland soils have more availability for Zn than
without freeze-thaw cycles.
Source: Monokrousos et al. ; MBC=microbial biomass of C, MBN=biomass of N, SE=standard error.
Monokrousos et al.  showed that the concentration of
microbial biomass C (MBC), biomass N, organic N, NH4+ and NO-3
by using three temperature regimes, increase in temperature
increased MBC rationalized by increase in decomposing
microbial activities in response to the temperature (Table 1).
Monger  concluded that, soil organic carbon is a soil
property that responds to climate change more quickly than the
others. While, pedogenic carbonate and clay content responds
less rapidly to climate and has a more gradual increase with
time during wetter periods and finer soil particle accumulation
during drier periods.
Soils with a thermic or hyperthermic temperature regime
experiencing accelerated rates of mineral weathering and
decomposition may contribute low-activity clays and low
organic matter . Likewise, soil organic carbon is composed
of a wide range of organic matters having various decomposition
rates derived from, soil temperature and moisture, diversity and
abundance of organisms, association with soil minerals and
degree of aggregation .
As climate temperature is altered, the rainfall pattern and
intensity shift from its initial condition to unconsumed state.
One of the predicted effects of climate change is an increase
in the frequency of high-intensity storms, which would in turn
increase rainfall erosivity. Feddema and Freire  predicted
that average temperatures, continent wide, for the 2010-2039
periods are expected to increase by 1.33°C, resulting in a 119mm
increase in the potential evapotranspiration rate in Africa. At
the same time, precipitation is expected to decrease by 30mm
continent wide, resulting in net drying soil moisture.
Source: Jenny (2005) .
The influence of climate change on soil structure type, spatial
arrangement and stability of soil aggregates is a more complex
process. The apparent detrimental effects of climate change are
the aggregate-destructing role of raindrops, surface runoff and
filtrating water, especially during heavy rains, thunderstorms
and even rain bombs, the increasing hazard, frequency and
intensity of which are characteristic features of climate change
[29-31]. The indirect influences are caused by changes in the
vegetation pattern and land use practices . Accordingly, Jenny
 illustrated soils developed in regions of high temperature
tend to be high in clay but low in organic matter (Table 2).
Increase in temperature in hot and dry conditions results
in decrease in precipitation. The decrease in atmospheric
precipitation will in turn result in a decrease in water infiltration
and soil water holding capacity and plant available water. Consequently, surface runoff in hilly lands with undulating
surfaces causes water erosion hazard and will increase
evaporation losses .
According to Monger , soils erosion has stripped away
the A and B horizons of the soils and exposed underlying calcic
horizons. As a result of the calcic horizons are brought into the
shallow, more intense weathering zone of increased biologic
activity above the depth where pedogenic carbonate normally
forms, the possibility arises that such exhumed carbonates are
active sources of CO2 emissions.
Different anthropogenic activities and natural processes
contributed CO2 to atmosphere, which is alarming global
temperature. Consequently, different recent research results
predicted that the atmospheric temperature would reach at the
point beyond environmental temperature tolerance in nearby
future. The temperatures, above its optimum point, impose
detrimental effects on all systems with which it openly exchanges
matter and energy take place. Soil is among the system that
shares all consequences attributed to the climate change.
Different scientists devoted to elaborating that there
was proportional linear correlation between atmospheric
temperature and soil temperature. In response to the climate
change, soil biota, soil physicochemical properties and soil
morphology will get altered. To some extent, increase in soil
temperature accelerates chemical reaction and biological
activities that take place within the soil system. Nevertheless,
the consequences of increased global temperature above
threshold level brings the disruption of soil function that result
in soil fertility loss in terms of biological, chemical, physical
and morphological aspects. This, in turn, hinder the goods and
services provided by soil on which all organisms rely.
Even though atmospheric and soil temperature are positively
correlated, the strength of the correlation (R2) between soil and
air temperature varies according to the soil type, soil color, land
use systems and other environmental conditions. Therefore,
there is a need to study soils of all agro ecology response to
atmospheric temperature fluctuation. Besides, concerned soil
scientists should engage in and collaborate with natural resource
managers to alleviate the effects of global warming on our soils.