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2.5.1 INTRODUCTION
The Lebanese topography is such that only about one-third of land
area is arable, and cultivation is confined to around 22% (1). The
agricultural sector employs about 11% (1) of the active population
and contributes only in an estimated 10 %(1) of national income.
A. CROPS
The Bekaa valley is the dominant agricultural region where a wide
range of crops mainly potatoes, tomatoes and sugar beet are grown .
South Lebanon is a wheat growing region while the coastal zone from
the north to the south supports an intensive agriculture, primarily
citrus, fruits, bananas and vegetables. Cereals are largely produced
in the north of Lebanon especially in Akkar .
B. LIVESTOCK
Livestock is particularly concentrated in Akkar and in the Bekaa
area. Livestock production contributes only an estimated 15% (1) of
the domestic market. Cattle and dairy farming are of minor
importance; bovines of all kinds are vastly outnumbered by sheep and
goats. Poultry farming is in increasing development. In summary,
Lebanon has become a large-scale exporter of fruits, vegetables and
poultry, but remains a net importer of animals, dairy products,
cereals and poultry foodstuff.
2.5.2 DOMESTIC LIVESTOCK
This section deals with methane and nitrous oxide emission from two
sources:
- Enteric fermentation
- Manure management
Enteric fermentation contributes to methane emission as a by-product
of the digestive process.
Manure management leads, under different conditions, to the emission
of methane and nitrous oxide.
For estimation purposes, the revised default methodology developed
by the IPCC (2) was followed.
The data needed to estimate methane and nitrous oxide emissions are
provided from the FAO production year book -1994 (3). The table 4-1
summarizes these data. |
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Table 2.29
Livestock Population
|
|
Livestock type |
Number of animals
(1000s) |
|
|
1992 |
1993 |
1994 |
average |
|
Cattle |
73 |
77 |
80 |
76.7 |
|
Dairy Cattle |
45 |
47 |
|
46.0 |
|
Non-dairy Cattle |
28 |
30 |
|
30.7 |
|
Sheep |
240 |
250 |
258 |
249.3 |
|
Goats |
465 |
450 |
456 |
457.0 |
|
Camels |
1 |
1 |
1 |
1 |
|
Horses |
11 |
12 |
13 |
12.0 |
|
Mules and Asses |
30 |
31 |
33 |
31.3 |
|
Swine |
42 |
40 |
41 |
41.0 |
|
Poultry |
20000 |
24000 |
24000 |
227700.0 |
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In the
last column of table 2.29 each number is a three year average except
that of
dairy cattle which is a two year average. The number of non-dairy
cattle is obtained
by subtracting the two year average of the dairy cattle from the
average of the total
number of cattle. |
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A.
METHANE EMISSION FROM DOMESTIC LIVESTOCK
To estimate the emission of methane from domestic livestock,
emission factors are needed. These factors are not available,
therefore default values of the emission factors presented in the
IPCC Reference Manual (2) for enteric fermentation and manure
management are used
B. NITROUS OXIDE EMISSIONS FROM DOMESTIC LIVESTOCK
- The default value (18%) presented in the IPCC- workbook (4), in
the used fuel system for dairy and non-dairy cattle is not
appropriate for Lebanon
- The default value (77%) presented in the IPCC workbook (4) , in
Pasture Range and Paddock system for dairy and non- dairy cattle
seems to be high for Lebanese cattle farming.
This can be justified by considering the following:
- Personal field survey and interviews with farmers showed that
animal waste is not used as fuel in the Hariri farm for cattle and
poultry, where there are about 1000 cattle and 4 million poultry.
The supervisor (5) of the farm confirmed the following:
1- Animal waste is not used as fuel. This confirmation comes from
small, and large farms.
2- Animal waste is stored in the form of dry lots in a small area.
3- Successively half of the cattle go daily to pasture.
- A great number of cattle stay near the farmhouses and therefore
animal waste is treated in the drylot system.
- Information from the president of the south farmers congregation
(6) indicate the following:
1- Animal waste burning as fuel is no more a Lebanese farmer's
practice.
2- On the farms, animal waste is managed in solid storage and drylot
system.
- There are no natural pastures in Lebanon except for some farms
where we found a small area used as pasture (5,6).
From this we can conclude that, for Lebanon, the default value 77%
(4) for cattle in pasture range and paddock system is high and that
the default values 3 and zero presented in solid storage and drylot
system (4) for dairy and non-dairy cattle respectively are very low.
Instead of these default values we estimate the following values:
- 50% of animal waste for dairy and non-dairy cattle are deposited
in pasture range and paddock system. This value is used in the
worksheet 4-1 (supplemental) Pasture Range and Paddock.
- 48% of animal waste for dairy cattle and 46% for non-dairy cattle
are managed in solid storage and drylot system. These two values are
used in the worksheet 4-1(supplemental) solid storage and drylot
system.
- 0% of animal waste is used as fuel. This value is used in the
worksheet 4-1(supplemental) used fuel.
2.5.3 FIELD BURNING OF AGRICULTURE RESIDUES
Important quantities of residues are produced from agricultural
crops. Several broad categories of crop residues can be
distinguished:
- Cereal residues like wheat straw and maize stalks
- Residues from pulse
- Residues from tuber and root
- Residues from legumes
Burning of crop residues in the fields can lead to the emission of
the following gases:
CO2, CO, CH4, N2O and NOx .
This section accounts for emission of the non-CO2 gases. The data
required for the estimation of the emission of the above mentioned
gases from crop residues are provided from FAO production yearbook
(3)-1994. This data is presented in table 2.30. |
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Table 2.30
Annual Production of Crops from which Some Residues are Burned
|
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Crop |
Annual Production (Gg Crop ) |
|
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1992 |
1993 |
1994 |
Average |
|
Wheat
Barley
Oats |
62
21
1 |
50
20
1 |
39
22
1 |
50.333
21.000
1.000 |
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We have
selected only these crops for the following reasons:
Field survey (7) in the Bekaa, information from the south farmers
congregation (6) and interviews with experts (8) showed that in the
Bekaa, south-Lebanon and Akkar, the most important agricultural
centers, large quantities of crop residues provide an important
source of animal feed and at least are collected for this purpose by
farmers and stored for the animals.
The fraction of residues remaining in fields after harvest is also
used as feed in the case of some cereals like wheat, barley and
oats. Sometimes it is partly burned because of agricultural disease
(8).
The residues of all other crops are collected and thrown as waste or
left on fields.
From this we can conclude that field burning of agricultural
residues is not a common practice in Lebanon therefore the fraction
burned in fields is estimated to be 1%. This value is used in the
worksheet 4-4 sheet 1 of 3 step 3. In work sheet 4-4 sheet 1 of 3
the residue to crop ratio used for oat is 1.3, the same as for
wheat, because of similarity of oat to the wheat .
2.6.4 AGRICULTURAL SOIL
Agricultural soils emit N2O from three sources:
- Direct emission from agricultural soils that results from the
nitrification and denitrification processes. This is particularly
observed in organic soils.
- Direct soil emissions from animal waste management systems. This
type of N2O emission results from dung and urine deposited by
free-range grazing animals.
- Indirect N2O emission from nitrogen used in agriculture and
resulting from the use of fertilizer.
In order to estimate N2O emission from agricultural soils, the
following data is needed:
- Synthetic nitrogen fertilizer consumption. This is available from
FAO fertilizer year book (9) - 1996. This data is presented in table
2.31.
- Crop production which is available from FAO production yearbook
(3) -1994. Table 4-4 summarizes this data.
- Livestock population in table 2.31 section 2.32. |
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Table 2.31
Annual Consumption of N-Fertilizer
|
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|
1992 |
1993 |
1994 |
average |
|
Annual
Consumption of N-Fertilizer ton-N/yr |
12400 |
14200 |
18000 |
14866.6 |
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Table 2.32
Annual Production of Crops
|
|
Crop |
Annual Crop
Production 1000t/yr |
|
|
1992 |
1993 |
1994 |
Average |
|
Cereals (a) |
116 |
103 |
96 |
104.9 |
|
Pulses (b) |
62.1 |
64.0 |
67.5 |
64.5 |
|
Tubers and Roots
(c) |
512 |
519 |
555 |
528.6 |
|
Other (d) |
715 |
724 |
773 |
737.3 |
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a)
Includes: wheat, coarse grain, barley, maize oats and sorghum.
b) Includes: dry beans, broad beans, peas, chick peas, lentils,
green beans and green peas.
The FAO data of green beans and green peas are multiplied by
(1-0.15) to account for crop water content.
(c) Includes: Potatoes, sugar beet and carrots.
(d) Includes: Taro, groundnut, cottonseed, cabbage, artichoke,
cauliflower, tomatoes, pumpkin,
cucumbers, onion, garlic, watermelon, cantaloupe, sugar cane, and
tobacco leaves. |
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A. In the worksheet 4-5 A (supplemental ) sheet 1 of 1:
Faw is calculated by considering Frac GRAZ = 0.6 . This value is
obtained from the following :
Frac GRAZ = Nex GRAZ
Nex
Frac GRAZ = 25421.1x103 =0.6
42106.7x103
FCR is calculated by considering
Frac BURN = fraction burned in fields for all crops
crop BF+ crop 0
Frac BURN = 0.717 Gg = 5 x10-4
(64.5 +12770.8) Gg
This formula can be explained as follow:
The total quantity of crop residues results by subtracting the FAO
crop production from total crop biomass production.
The total crop biomass is obtained by multiplying the FAO crop
production by the factor 2 [ 4].
FAO crop production = Production of pulses + soy beans in country
(crop BF) + production of non-N fixing crops in country( crop 0)
FAO crop production = crop BF + crop 0
From the above mentioned explanation it can be concluded that:
Total quantity of crop residues = FAO crop production = crop BF +
crop 0
In Lebanon, some fraction only of wheat, barley and oats is burned
in field. The estimated fraction burned, 1%, belongs specifically to
wheat, barley and oats. From this value and the annual production of
wheat, barley and oats, the quantity of crop residues burned in
field can be obtained.
Fraction burned for all crop residues results from the following:
Frac BURN= quantity of residue burned in field
Total quantity of crop residues
Frac BURN= quantity of residue burned in field
Crop BF + crop 0
Where:
Crop BF= production of pulses + soybeans in country (kg dry biomass
/ yr)
Crop 0 = production of non- N- fixing crops in country (kg dry
biomass / yr)
Quantity of residue burned in field=71.7x 0.01=0.717 Gg (worksheet
4-4, sheet 1 of 3)
Crop BF = 64.5 Gg ( table 4-4 Annual production of crops)
Crop 0 = 12770.8 Gg ( table 4-4 Annual production of crops)
The value 12770.8 results from the sum of the annual production of
cereals, tubers and roots and other ( table 4-4 Annual production of
crops)
Frac BURN = 0.717 = 5 x 10-4
12770.8 + 64.5
B. In the worksheet 4-5 sheet 2 of 5:
The value of Fos is estimated to be null. Information from experts
(10) confirmed that there is no organic soil in Lebanon.
Faw = manure nitrogen used as fertilizer in country, corrected for
NH3 and
NOx emissions and excluding manure produced during grazing (kg N/yr)
Frac GRAZ = fraction of livestock nitrogen excreted and deposited
onto soil
during grazing (kg N / kg N excreted).
Nex GRAZ = nitrogen excretion during grazing (worksheet 4-1)
(supplemental), Pasture Range and Paddock system (kg N/yr).
Nex = total nitrogen excretion by animals in country (kg N/yr).
Frac BURN = fraction of crop residue that is burned rather than left
on field.
Click here to view
Table 2.33
References
- J . Hayek, K. Abou Alfa, R. Aboud, The Contemporary Geography,
Lebanon and the Arabic countries, (schoolbook ), 3rd secondary
class, 1993, (in Arabic).
- Revised 1996 IPCC guidelines for national greenhouse gas
inventories: Reference Manual, Volume 3
- FAO (1994), yearbook-production volume 48, United Nations, Italy.
- Revised 1996 IPCC Guidelines for national greenhouse gas
inventories: workbook volume 2.
- Akle Yaghi, Engineer Agronom, supervisor of the Hariri farm,
Bablieh-south Lebanon.
- Waddah Fakhri, President of the south farmers congregation, Saida-Lebanon.
- Nasser Chreif, Plant-expert, Yammouneh-Lebanon.
- Mohamad Rifai, Professor at the Lebanese University, Faculty of
sciences , Beirut-Lebanon.
- Khaled Zahraman , Researcher in the NCSR, Beirut-Lebanon
- Samih Hajj, Professor at the Lebanese University, Faculty of
Agronomy, Beirut-Lebanon
- FAO (1996) , yearbook - Fertilizer, United Nations Italy.
- Talal Darwich, Researcher in the NCSR, Beirut-Lebanon |
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