Facing Climate Change: Urban Gardening and Sustainable …
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Gardeners, also, may add nitrous oxide to the environment by applying nitrogenous fertilizers, especially if it is applied to young plants when plants cannot make
use of the nitrogen, Burning garden waste [27]. So, Nitrogen dioxide is a major
component of the complex of photochemical air pollutants in urban areas.
Plant leaves can absorb many kinds of gaseous air pollutants, including NO 2 ,
through their stomata, and consequently, they have a capacity to remove this gas from
the surrounding atmosphere [28]. NO 2 absorbed by the leaves can be converted into
nitrate and nitrite, and then rapidly assimilated into organic nitrogenous compounds.
A powerful greenhouse gas produced by soil cultivation practices, especially the
use of commercial and organic nitrogenous fertilizers, fossil and gas fuel combustion,
nitric acid production, and biomass burning.
Soil Nitrous oxide emissions originate from three sources [29].
(a) Soil microorganism activity (55%);
(b) Organic manure applications (18%); and
(c) Nitrogen fertilizer applications (27%).
2.4 How Does Nitrogen Fertilizer Increase Nitrous Oxide
Emissions?
Gardeners add new N to parks and all types of gardens as synthetic fertilizers such
as urea or anhydrous ammonia, or rarely as organic fertilizers. When not taken up by
plants, most fertilizer N is mobile, hard to contain in the field and susceptible for loss.
Nitrogen from fertilizer can be lost as nitrate to groundwater or as the gases N 2 O,
dinitrogen (N 2 ) or ammonia. Nitrogen applied in excess is particularly susceptible
for loss. Though the amounts of carbon and oxygen available in the soil also affect
microbial N 2 O production [30].
2.5 Management of Nitrogen Fertilizer to Decrease Nitrous
Oxide Emissions
Numerous management strategies can keep soil N in check and minimize N 2 O emissions. Many of these strategies also help to keep other forms of N from being lost,
including nitrate and ammonia. In general, practices that reduce N 2 O emissions
increase N use efficiency (NUE), which keeps more of the added N in the crop.
The four main management factors that help reduce N 2 O emissions from applied N
fertilizer are commonly known as the 4R’s [31].
• Right N application rate;
• Right formulation (fertilizer type);
• Right timing of application; and,
351
Gardeners, also, may add nitrous oxide to the environment by applying nitrogenous fertilizers, especially if it is applied to young plants when plants cannot make
use of the nitrogen, Burning garden waste [27]. So, Nitrogen dioxide is a major
component of the complex of photochemical air pollutants in urban areas.
Plant leaves can absorb many kinds of gaseous air pollutants, including NO 2 ,
through their stomata, and consequently, they have a capacity to remove this gas from
the surrounding atmosphere [28]. NO 2 absorbed by the leaves can be converted into
nitrate and nitrite, and then rapidly assimilated into organic nitrogenous compounds.
A powerful greenhouse gas produced by soil cultivation practices, especially the
use of commercial and organic nitrogenous fertilizers, fossil and gas fuel combustion,
nitric acid production, and biomass burning.
Soil Nitrous oxide emissions originate from three sources [29].
(a) Soil microorganism activity (55%);
(b) Organic manure applications (18%); and
(c) Nitrogen fertilizer applications (27%).
2.4 How Does Nitrogen Fertilizer Increase Nitrous Oxide
Emissions?
Gardeners add new N to parks and all types of gardens as synthetic fertilizers such
as urea or anhydrous ammonia, or rarely as organic fertilizers. When not taken up by
plants, most fertilizer N is mobile, hard to contain in the field and susceptible for loss.
Nitrogen from fertilizer can be lost as nitrate to groundwater or as the gases N 2 O,
dinitrogen (N 2 ) or ammonia. Nitrogen applied in excess is particularly susceptible
for loss. Though the amounts of carbon and oxygen available in the soil also affect
microbial N 2 O production [30].
2.5 Management of Nitrogen Fertilizer to Decrease Nitrous
Oxide Emissions
Numerous management strategies can keep soil N in check and minimize N 2 O emissions. Many of these strategies also help to keep other forms of N from being lost,
including nitrate and ammonia. In general, practices that reduce N 2 O emissions
increase N use efficiency (NUE), which keeps more of the added N in the crop.
The four main management factors that help reduce N 2 O emissions from applied N
fertilizer are commonly known as the 4R’s [31].
• Right N application rate;
• Right formulation (fertilizer type);
• Right timing of application; and,