2010.greenhouse gas emissions of the agricultural and livestock products in china

7/31/2019 2010.Greenhouse Gas Emissions of the Agricultural and Livestock Products in China

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Greenhouse Gas Emissions of the Agricultural and Livestock

Products in China

WANG Xiaoqin

College of Resources and Environment, Northwest A&F University, Yangling, China, 712100

[email protected]

Abstract According to the agricultural production materials and energy consumption of national

average, GHG emissions from the per unit of Agricultural and livestock product in China was assessed.

The results show that GHG emissions from the per unit of agricultural products are from 0.1 to 0.4

KgC2O-eq/Kg except of rice which is 1.42KgC2O-eq/Kg and GHG emissions from the per unit

livestock products are from 0.7 to 13.47 KgC2O-eq/Kg which is 1.8-13 times of Agricultural products.

So Emphasis of reducing emissions from agriculture should focus on livestock production The

effective way to reduce personal emissions is consumpting less of livestock products, In particular,

should reduce beef, mutton and pork consumption.Keywords: agricultural products, livestock production, GHG

1. IntroductionAgriculture is the main source of greenhouse gas(GHG) it is important reducing GHG emissions of

agricultural sources to control global climate change. China is a populous agricultural country the

Chinese agriculture source GHG emissions accounted for China total GHG emissions quantity 17% in

1994 according to The Peoples Republic of China Initial National Communication on Climate Change.

If there is no corresponding emission reduction measures, agricultural sources of greenhouse gas

emissions will be correspondingly larger[1]

. Most studies on agricultural GHG emissions, focused on

methane emissions in rice and agricultural nitrous oxide emissions, less of it assessed agricultural and

livestock products GHG emissions throughout the production process. Effective emission reduction

policies will not only require the government to guide the development of agriculture in low-carbon, but

also require consumers to choose low-carbon agricultural and livestock products. This paper will

assessed GHG emissions of China's major agricultural and livestock products based on China's yield,

materials and energy consumption of agricultural production. It can help government and consumers to

understand all kinds of agricultural and livestock products GHG emission, to draw up agricultural

mitigation policies for government, and choose low-carbon agricultural products for consumers.

2. Method of Calculation2.1 The calculation method of agricultural products GHG emissions

GHG of Crop production mainly include CO2

from the fertilizer production process, and N2O from field

because of nitrogen fertilizer, In addition to CH4 from Paddy field.Calculated as follows:

PNNPMMPCPP /QGWPEGWPEEE ++= 1

where EP is greenhouse gases emissions per unit agricultural product in CO2 equivalent (kgCO2-eq

/kg) ,ECP is CO2 emissions per acres crops(kg), EMP is CH4 emissions per acres crops(kg), ENP is

N20 emissions per acres crops(kg), GWPN is global warming potential of N20, GWPM is global warming

potential of CH4 , QP is Crop yield per acres( kg).

NNCP TefE = 2

where efN is CO2 emissions of unit nitrogen fertilizer production(kgCO2/Kg-N),TN is nitrogen fertilizer

consumption quantity (pure discount) per acres(kgN/ acres).


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28

44TefE NNNNP = 3

where efNN is N20 emissions factor of field( kgN2O-N/kgN),4428 is N20-N(MMS) Conversion to N2O(MMS).

2.2 The calculation method of livestock products GHG emissions

GHG emissions of livestock products is mainly from feed production process and animal breeding

process. GHG emissions in feed production process inculd emissions from feed grain production and

concentrated feed processing. GHG emissions in breeding process mainly inculd CH4 emissions from

Intestinal gas and feces, N2O from feces of livestock and poultry animals, and CO2 emissions related

with energy consumption. Calculated as follows:

ANNAMMACAA /QGWPEGWPEEE ++= 4

where EA is GHG emissions per unit livestock product in CO2 equivalentkg(CO 2-eq /kg), ECA is CO2emissions per head livestock and poultry animal during breeding(kg/h), EMA is CH4 emissions per head

livestock and poultry animal during breeding(kg/h), ENA is N20 emissions per head livestock and poultryanimal during breeding(kg/h), QA is output per head livestock and poultry during breeding(kg/h).

CPPOWCCOLCOLCjjPiPi fWfWfWWE +++=CAE 5

whereEpi is GHG emissions per unit feed grain production(kgCO2-eq /kg), Wpiis consumption of grain

per head livestock and poultry animal during breeding(kg/h), Wj is consumption of concentrated feed

per head animal during breeding(kg/h), fCj is CO2 emissions per unit concentrated feed processing Kg/

Kg ,WCOL is consumption of coalper head animal during breeding(kg/h), fCCOL is CO2 emissions factor

of coal combustion Kg /Kg , WPOW is consumption of electricity per head animal during breeding

KWh /h , fCP is CO2 emissions factor of electricity production Kg/KWh .

MFMCMA ffE += 6

where fmcis CH4 emissions from intestinal gas per head animal during breeding Kg /h. , fmfis CH4

emissions from feces per head animal during breeding Kg / h. .

28

44MFfFraclfFrachfE NLNHNZNA ++= 7

where fNZ is N2O direct emissions factor KgN2O-N / KgN , fNH is N2O indirect emissions factor

because of volatile KgN2O-N / KgN , Frach is nitrogen volatilization ratio through NH3 and NOx from

fecal, fNL is N2O indirect emissions factor because of leaching KgN2O-N / KgN , Fracl is nitrogen

losses ratio because of leaching, F is manure emission factors per head animal during breeding Kg / h ,

M is nitrogen content of manure.

3. Sources of Data and Calculation Results3.1 GHG emissions per unit agricultural product

Major cereals, vegetables and some fruits are selected to calculate their GHG emissions, according to

the availability of the data. The date of agricultural product yield and nitrogen fertilizer consumption

quantity is from Compilation of National Costs and Benefits of Agricultural Products (2008)[2]

. The

value of N20 emissions factor of field is based on Chinese Greenhouse Gas Emission Inventory

Research [3] the emissions factor of CO2 of unit nitrogen fertilizer production is 6KgCO2/KgN, which

was calculated based on the national yield and energy consumption of nitrogen fertilizer in china. The

emissions factor of CH4 of paddy is a national average value, 22KgCH4/a, which was calculated based

on the national rice yield and total CH4 emissions from national paddy[4]

. Global warming potential

value of N20 and CH4 are 298 and 25 respectively. The parameters and calculation results shown in

Table 1.


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Table 1. parameters and GHG emissions per unit agricultural product

3.2 GHG emissions per unit animal product

Livestock products selected to assess are pork, beef, milk, mutton, chicken and eggs .The data of yield,

feeding period, Concentrated feed consumption, grain consumption, coal consumption, and electricity

consumption per head animal during breeding, are national average which are directly from Compilation

of National Costs and Benefits of Agricultural Products or calculated based on statistical data. Pigs,

cattle, sheep and chickens product yield per head are dead weight. Because electricity consumption per

unit concentrated feed processing is 30KWh/t[5]

and CO2 emissions factor of electricity production is

0.997 Kg/ KWh[6] CO2 emissions per unit concentrated feed processing is 0.299 Kg. Feed grain mostly

is corn in China, so GHG emission from feed grain consumption is calculated based on corn GHG

emission. The date of CH4 emissions from intestinal gas, manure emission factors and nitrogen content

of manure per head animal during breeding are from Chinese Greenhouse Gas Emission Inventory

Research. The date of CH4 emissions from feces is based on the study of Zhang Renjian. N2O direct

emissions factor from feces is a national average value, which is calculated weighting according to the

ratio of different manure management on total in china and N2O direct emission factor on the different

manure management condition recommended by IPCC. N2O indirect emissions factor because of

volatile and leaching are 0.01, 0.0075 respectively. The nitrogen losses ratio because of volatile and

leaching are 20%, 30% respectively according to default value of IPCC. The CO2 emissions factor of

coal combustion is 2.493 Kg/ Kg. The parameters and calculation results shown in Table 2

Table 2. Parameters and GHG emissions per unit animal product

pork beef mutton chicken eggs mike

output per head animal Kg/h 76.8 264.5 18.3 1.8 16.5 5338.1

consumption of concentrated feed Kg/h 272.4 380.5 55.3 5.2 39.24 2860.8

consumption of corn Kg/h 192.4 270.8 39.0 3.6 27.7 2021.9

consumption of electricity KWh/h 6.20 13.42 3.48 0.22 0.10 6.2

consumption of coal Kg/h 8.5 16.45 2.83 0.34 0.32 8.5

CH4 emissions from intestinal gas Kg/h 1.00 77.5 8.2 0 0 79.3

YieldKg/a

N- fertilizer

consumption

Kg/a

N20 emissions

factor of field

KgN2O-N/KgN

GHG emissions per unit

agricultural product

KgC2O-eq/Kg

Rice 450.2 10.85 0.0045 1.42

Wheat 359.9 13.49 0.0057 0.32

Corn 422.4 13.03 0.0057 0.27

Soya bean 110.1 4.11 0.0057 0.32

Apple 1726.8 23.98 0.0057 0.12

Citrus 1631.8 12.48 0.0057 0.07

Orange 2038.2 13.15 0.0057 0.06

Tomato 4908.4 27.11 0.0087 0.25

Cucumber 4495.8 31.81 0.0087 0.33

Eggplant 3417.4 23.80 0.0087 0.32

Vegetable pepper 2699.7 22.96 0.0087 0.40

Open field cabbage 4247.1 19.87 0.0087 0.22

Open ground potato 1790.2 10.71 0.0087 0.28

Open field cauliflower 2097.4 14.75 0.0087 0.33

Open field radish 3137.3 7.82 0.0087 0.12

Open field beans 1947.7 6.53 0.0087 0.16


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CH4 emissions from manure Kg/h 3.05 0.77 0.10 0.016 0.016 8.87

emissions of manure Kg/h 826.8 7700 500.5 6.4 53.3 19400

nitrogen content of manure % 0.238 0.438 0.898 1.032 1.032 0.438N2O direct emissions factor KgN2O-N/ KgN 0.007 0.0094 0.005 0.005 0.005 0.0094

GHG emissions per unit animal product

KgC2O-eq/Kg 2.57 8.65 13.47 1.54 0.78 0.70

4. ConclusionIt is known according results that GHG emissions from the per unit of Agricultural products are from 0.1

to 0.4 KgC2O-eq/Kg except of rice which is 1.42KgC2O-eq/Kg and GHG emissions from the per unit

livestock products are from 0.7 to 13.47 KgC2O-eq/Kg which is 1.8-13 times of agricultural products.

So Emphasis of reducing emissions from agriculture should focus on livestock production The

effective way to reduce personal emissions is consumpting less of livestock products, In particular,

should reduce beef, mutton and pork consumption, of which GHG emission are 8.65, 13.47, and 2.57KgC2O-eq/Kg respectively.

Since this calculation is based on the national average agricultural statistics, it is only a rough estimate

results. Because of the lack of some data, agricultural products GHG emissions ignore the emissions

related with energy consumption, andanimal products GHG emissions ignored emissions related with

the feed transport and animal slaughter, the results in this paper is lower. The results is lower than EUs,

one of reason is ignoring some emissions in our study, another is that backyard farmers is the main form

of animal husbandry in China, in which the crude feed account for a greater proportion of total feed.

References

[1]. Dong Hongmin Li Yue, Tao Xiuping, et al.China greenhouse gas emissions from agriculturalactivities and its mitigation strategy. Transactions of the CSAE.2008,.24(10):269-273(in Chinese).

[2]. Bureau of Statistics of China. Compilation of National Costs and Benefits of Agricultural Products.Beijin Bureau of Statistics of China. 2008(in Chinese).

[3]. Cai Bofeng, Liu Chunlan, Chen Caoao, et al. Citys Greenhouse Gas Emission InventoryResarch .Beijing:Chemical Industry Press.2009(in Chinese).

[4]. Zhang Renjian, Wang Mingxing, Li Jing, et al. The Present Status of the Emission Methane inChina. Climatic and Environmental Resear,1999 ,4 (2) :194 202(in Chinese).

[5]. Bai Lin, Li Xuewei, He Jiaguo, et al. The Study on LCA of Pork Production In Xichuan. ChineseJournal of Animal Science.2009, 45(22):38-42(in Chinese).

[6]. Energy Save Center, Xiamen. How to calculate the carbon dioxide emission reductions [EB /OL].2008-2-14 http://xmecc.xmsme.gov.cn/2008-2/2008214165039.htm(in Chinese).

2010.greenhouse gas emissions of the agricultural and livestock products in china

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