كليدواژه :
هندوانه , ضريب انتشار , سيب زميني , پياز , آفت كش , اوره
چكيده لاتين :
Introduction
The latest report of the IPCC states that future emissions of greenhouse gases (GHGs) will continue to
increase and will be the main cause of global climatic changes, as well as Iran. The three greenhouse gases
associated with agriculture are CO2, CH4, and N2O. Chemical inputs consumption in agriculture has increased
annually, while more intensive use of energy led to some important human health and environmental problems
such as greenhouse gas emissions and global warming. Therefore, it is necessary to reduce the application of
chemical inputs in agricultural systems. Agriculture contributes significantly to atmospheric GHG emissions,
with 14% of the global net CO2 emissions coming from this sector. Chemical inputs have a major role in this
hazards.
There is even less data on CO2, N2O, and CH4 gas emission analysis as affected by cultivating various crops
in Kerman province. Therefore, this study was conducted to assess the GHGs emission and Global warming
Potential GWP caused by chemical inputs (various chemical fertilizers and pesticides) for cultivating potato,
onion and watermelon in some regions of Kerman province at 2011-2012 growth season.
Material and Methods
The study was conducted in Kerman province of Iran. Data of planting area, application rates of the chemical
inputs and other different parameter were collected from potato, onion and watermelon growers by using a face
to face questionnaire in 2014 for different regions of Kerman(Bardsir, Bam, Jiroft, Kerman, Ravar, Rafsanjan
and Sirjan). In addition to the data obtained by surveys, previous studies of related organization (Agricultural
Ministry of Kerman) were also utilized during the study. Farm random sampling was done within whole
population and the sample size was determined by proper equations.
The amounts of GHG emissions from chemical inputs in the studied crops were calculated by using CO2,
N2O and CH4 emissions coefficient of chemical inputs. Then the amount of each GHG changed into CO2using
the specific GWP of each gas, which is the warming influence relative to that of carbon dioxide.
Results and Discussion
The results showed that N and P fertilizers had the highest application share of chemical inputs. Among the
studied crops, the highest amount of chemical fertilizers was used in potato. Potato and watermelon were
obtained the highest doses of herbicide and pesticide application, respectively. The results demonstrated that in
all these three crops, the highest and lowest GHGs emission was related to Jiroft and Rafsanjan, respectively.
The amount of annual GHGs emission was related to the regions planting area. The highest share of emission gas
in all the three crops and all regions was related to CO2. In potato and onion, herbicide was caused higher CO2
emission compared to insecticide and fungicide. Watermelon cultivation contained no herbicide application.
GWP in the studied regions had the same trend with GHGs emission. In all three studied crops, Jiroft and
Sirjan were obtained the highest and lowest values of annual GWP, respectively. In all studied crops, N fertilizer
led to more GHGs emission in comparison to other inputs. Potato had the highest emission of CO2, N2O and CH4 followed by watermelon, and the lowest amount was gained in onion. Also, annual GWP of potato, watermelon
and onion were 6814.2, 6024.2 and 2125 ton CO2 equivalence, respectively. Among all chemical inputs, N
(91%), P (6.9%) and herbicide (1%) were involved the highest share in GWP for studied plants.
Conclusion
The results showed that in all three studied crops, the highest and lowest GHGs emission was related to Jiroft
and Rafsanjan, respectively. Annual GWP in the studied regions had the same trend with GHGs emission. In all
three studied crops, Jiroft and Sirjan were obtained the highest and lowest values of annual GWP, respectively.
In all studied crops, N fertilizer led to more GHGs emission in comparison to other inputs. Potato had the highest
emission of CO2, N2O and CH4 followed by watermelon, and the lowest amounts was gained in onion. Among
all chemical inputs, N (91%), P (6.9%) and herbicide (1%) were involved the highest share in GWP for studied
plants.
