practices, host species, and shade. More specifically, soil P level found to be an
indicator of VAMF diversity, whereas soil pH, soil inorganic N and P, soil moisture,
and shade exhibited a significant relationship over the VAMF community composition [169–171]. So the controversies existed in literature may arise due to different
site-specific conditions, soil texture, spatial location, and nature of work, etc.
Sustainable organic coffee production required a sustainable organic matter
specifically rich in macronutrients especially N and K. Livestock dung, composted
and crop residue, farmyard, and organic matter from natural system are the common
sources of OM. Despite fulfilling the OM contents of soil and its associated benefits,
the natural supply of NPK from all these kind of OM is <10% which is insufficient
to refurnish the exhausting soil and satisfying the nutrients demands of coffee plant
[172]. On other side, long term dependence only on mineral or inorganic fertilizers
may not be sustainable because of rendering the soil highly acidic, degrading, devoid
of soil microbial diversity, and having unstable soil aggregates. So, recently, a new
integrated approach of using both inorganic fertilizers and organic manure showed
promising results under the liberal supply of irrigation water. This integrated fertility
management system showed a comparable growth pattern to inorganic fertilization
by supplying the nutrients to coffee plant in lag phase during which organic manure
alone failed to immediately fulfill the coffee plant’s needs [172]. But scientific
literature still needs the data on consequences of this integrated fertility management
system on yield and quality. Industrial production of coffee also resulted in the
millions of tons production of coffee waste (i.e., husk, pulp and peel) which is highly
vulnerable to our environment due to its high contents in tannins and caffeine [173].
Besides this, coffee waste found to be rich in organic carbon (>50%) and the other
nutrients that are usually lacking in coffee soils (i.e., total N 1.27%, K 2.46%, and
with C/N ratio 40.02) [174]. So this coffee waste is under investigation for sustainable coffee production after its successful application in mushroom cultivation.
Santos et al. [175] failed to get significant results of using untreated coffee waste
in coffee fields due to high C/N ratio, higher fruit and leave drop, and higher
occurrences of fungal infestation. Compositing, and oxygen driven fermentation
procedure by the microbial communities, was also investigated as a favorable tactic
for lowering the C/N ratio and hiking the level of N and K [176]. The application of
composite material also reportedly improves the site-specific features, soil physical
characteristics, and soil texture [175]. Compositing approach is considered a good
approach for recycling of natural nutrients but like integrated fermentation management system, effects of composite material application on beverage quality are still
unknown.
2.5
Rainfall, Irrigation, Temperature, and Climate Change
This section basically deals with impact of rainfall, its correlating ambient day
temperature, drought, and solar radiation. But as fluctuations in temperature and
erratic rainfall pattern are generally perceived in the category of climate change
[177], so it is reasonable to discuss the impact of climate change here too. Coffee is a
670
A. Hameed et al.
indicator of VAMF diversity, whereas soil pH, soil inorganic N and P, soil moisture,
and shade exhibited a significant relationship over the VAMF community composition [169–171]. So the controversies existed in literature may arise due to different
site-specific conditions, soil texture, spatial location, and nature of work, etc.
Sustainable organic coffee production required a sustainable organic matter
specifically rich in macronutrients especially N and K. Livestock dung, composted
and crop residue, farmyard, and organic matter from natural system are the common
sources of OM. Despite fulfilling the OM contents of soil and its associated benefits,
the natural supply of NPK from all these kind of OM is <10% which is insufficient
to refurnish the exhausting soil and satisfying the nutrients demands of coffee plant
[172]. On other side, long term dependence only on mineral or inorganic fertilizers
may not be sustainable because of rendering the soil highly acidic, degrading, devoid
of soil microbial diversity, and having unstable soil aggregates. So, recently, a new
integrated approach of using both inorganic fertilizers and organic manure showed
promising results under the liberal supply of irrigation water. This integrated fertility
management system showed a comparable growth pattern to inorganic fertilization
by supplying the nutrients to coffee plant in lag phase during which organic manure
alone failed to immediately fulfill the coffee plant’s needs [172]. But scientific
literature still needs the data on consequences of this integrated fertility management
system on yield and quality. Industrial production of coffee also resulted in the
millions of tons production of coffee waste (i.e., husk, pulp and peel) which is highly
vulnerable to our environment due to its high contents in tannins and caffeine [173].
Besides this, coffee waste found to be rich in organic carbon (>50%) and the other
nutrients that are usually lacking in coffee soils (i.e., total N 1.27%, K 2.46%, and
with C/N ratio 40.02) [174]. So this coffee waste is under investigation for sustainable coffee production after its successful application in mushroom cultivation.
Santos et al. [175] failed to get significant results of using untreated coffee waste
in coffee fields due to high C/N ratio, higher fruit and leave drop, and higher
occurrences of fungal infestation. Compositing, and oxygen driven fermentation
procedure by the microbial communities, was also investigated as a favorable tactic
for lowering the C/N ratio and hiking the level of N and K [176]. The application of
composite material also reportedly improves the site-specific features, soil physical
characteristics, and soil texture [175]. Compositing approach is considered a good
approach for recycling of natural nutrients but like integrated fermentation management system, effects of composite material application on beverage quality are still
unknown.
2.5
Rainfall, Irrigation, Temperature, and Climate Change
This section basically deals with impact of rainfall, its correlating ambient day
temperature, drought, and solar radiation. But as fluctuations in temperature and
erratic rainfall pattern are generally perceived in the category of climate change
[177], so it is reasonable to discuss the impact of climate change here too. Coffee is a
670
A. Hameed et al.