Journal of Resources and Ecology >
Different Irrigation Methods and Their Comparisons Based on the Parametric Evaluation Method in Khosouyeh Dam Subbasin, Iran
Received date: 2018-11-27
Accepted date: 2019-04-08
Online published: 2019-10-11
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Today, the world's population is rising dramatically, and in line with this increase in the population of food and agricultural products, there must be an increasing in the number of problems associated with this process of agricultural land. Then it is necessary to use the maximum potential of this lands that product maximum yield without any damage. To reach this objective, land suitability evaluation is the most important way that can reach human to this objective. The main objective of this research was to compare different irrigation methods based on a parametric evaluation system in an area of 221402 ha in the Khosouyeh Subbasin of the Fars province, in the south of Iran. After preparing land unit map, 37 points were selected for sampling. Soil properties were evaluated and analyzed. Suitability maps for drop and gravity irrigation were generated using GIS technique. The results revealed land suitability of 98.42% of the case study was classified as permanently not suitable (N2) and 1.52% currently not suitable (N1) for gravity irrigation. On the other hand, land suitability of 77.73% of the case study was classified as permanently not suitability (N2), 6.05% currently not suitable (N1), 12.43% marginally suitable (S3) and 3.79% moderately suitable (S2) for drop irrigation. The limiting factors for both kinds of drop and gravity irrigation are soil depth and slope of land.
Key words: land suitability; drop irrigation; gravity irrigation
Masoud MASOUDI , Reza ZARE . Different Irrigation Methods and Their Comparisons Based on the Parametric Evaluation Method in Khosouyeh Dam Subbasin, Iran[J]. Journal of Resources and Ecology, 2019 , 10(5) : 504 -510 . DOI: 10.5814/j.issn.1674-764X.2019.05.005
Table 1 Suitability classes for the irrigation capability indices (CI) classes |
Capability index | Definition | Symbol |
---|---|---|
> 80 | Highly Suitable | S1 |
60-80 | Moderately Suitable | S2 |
45-59 | Marginally Suitable | S3 |
30-44 | Currently Not Suitable | N1 |
< 29 | Permanently Not Suitable | N2 |
Table 2 Soil depth rating for two kinds of gravity and drop irrigation |
Soil depth (cm) | Rating for gravity irrigation (%) | Rating for drop irrigation (%) |
---|---|---|
<20 | 30 | 30 |
20-50 | 60 | 70 |
50-80 | 80 | 90 |
80-100 | 90 | 100 |
>100 | 100 | 100 |
Table 3 Textural classes rating for two kinds of gravity and drop irrigation |
Textural classes | Rating for gravity irrigation | Rating for drop irrigation | ||||||||
---|---|---|---|---|---|---|---|---|---|---|
Fine gravel (%) | Coarse gravel (%) | Fine gravel (%) | Coarse gravel (%) | |||||||
<15 | 15-40 | 40-75 | 15-40 | 40-75 | <15 | 15-40 | 40-75 | 15-40 | 40-75 | |
Clay Loam (CL) | 100 | 90 | 80 | 80 | 50 | 100 | 90 | 80 | 80 | 50 |
Silty Loam (SiL) | 100 | 90 | 80 | 80 | 50 | 100 | 90 | 80 | 80 | 50 |
Sandy Clay Loam (SCL) | 95 | 85 | 75 | 75 | 45 | 95 | 85 | 75 | 75 | 45 |
Loam (L) | 90 | 80 | 70 | 70 | 45 | 90 | 80 | 70 | 70 | 45 |
Silty Loam (SiL) | 90 | 80 | 70 | 70 | 45 | 90 | 80 | 70 | 70 | 45 |
Silty (Si) | 90 | 80 | 70 | 70 | 45 | 90 | 80 | 70 | 70 | 45 |
Silty Clay (SiC) | 85 | 95 | 80 | 80 | 40 | 85 | 95 | 80 | 80 | 40 |
Clay (C) | 85 | 95 | 80 | 80 | 40 | 85 | 95 | 80 | 80 | 40 |
Sandy Clay (SC) | 80 | 90 | 75 | 75 | 35 | 95 | 90 | 85 | 80 | 35 |
Sandy Loam (SL) | 75 | 65 | 60 | 60 | 35 | 95 | 85 | 80 | 75 | 35 |
loamy Sand (LS) | 55 | 50 | 45 | 45 | 25 | 85 | 75 | 55 | 60 | 35 |
Sandy (S) | 30 | 25 | 25 | 25 | 25 | 70 | 65 | 50 | 35 | 35 |
Table 4 CaCO3 amount rating for two kinds of gravity and drop irrigation |
CaCO3 (%) | Rating for gravity irrigation | Rating for drop irrigation |
---|---|---|
<0.3 | 90 | 90 |
0.3-10 | 95 | 95 |
10-25 | 100 | 95 |
25-50 | 90 | 80 |
>50 | 80 | 70 |
Table 5 Elecrto-conductivity rating for two kinds of gravity and drop irrigation |
EC (ds m-1) | Rating for gravity irrigation | Rating for drop irrigation | ||
---|---|---|---|---|
C, SiC, S, SC textures | Other textures | C, SiC, S, SC textures | Other textures | |
< 4 | 100 | 100 | 100 | 100 |
4-8 | 90 | 95 | 95 | 95 |
8-16 | 80 | 50 | 85 | 50 |
16-30 | 70 | 35 | 75 | 35 |
> 30 | 60 | 20 | 65 | 20 |
Note: C: clay; SiC: silty clay; S: sand; SC: sandy clay |
Table 6 Drainage classes rating for two kinds of gravity and drop irrigation |
Drainage classes | Rating for gravity irrigation | Rating for drop irrigation | ||
---|---|---|---|---|
C, SiC, SC textures | Other textures | C, SiC, SC textures | Other textures | |
Well drained | 100 | 100 | 100 | 100 |
Moderately drained | 80 | 90 | 100 | 100 |
Imperfectly drained | 70 | 80 | 80 | 90 |
Poorly drained | 60 | 65 | 70 | 80 |
Very poorly drained | 40 | 65 | 50 | 65 |
Drainage status not known | 70 | 80 | 70 | 80 |
Note: C: clay; SiC: silty clay; SC: sandy clay |
Table 7 Slope rating for two kinds of gravity and drop irrigation |
Slope classes (%) | Rating for gravity irrigation | Rating for drop irrigation | ||
---|---|---|---|---|
Non-Terraced | Terraced | Non-Terraced | Terraced | |
0-1 | 100 | 100 | 100 | 100 |
1-3 | 95 | 95 | 100 | 100 |
3-5 | 90 | 95 | 100 | 100 |
5-8 | 80 | 95 | 90 | 100 |
8-16 | 70 | 85 | 80 | 90 |
16-30 | 50 | 70 | 60 | 70 |
>30 | 30 | 50 | 40 | 50 |
Table 8 Distribution of gravity and drop irrigation suitability |
Suitability | Drop irrigation | Gravity irrigation | ||
---|---|---|---|---|
Area (ha) | Ratio (%) | Area (ha) | Ratio (%) | |
N2 | 172098 | 77.73 | 218040 | 98.48 |
N1 | 13403 | 6.05 | 3362 | 1.52 |
S3 | 27510 | 12.43 | — | — |
S2 | 8391 | 3.79 | — | — |
Total | 221402 | 100 | 221402 | 100 |
Table 9 CI values and suitability classes in gravity and drop irrigation for each land units |
Class of land unit | Gravity irrigation | Drop irrigation | Class of land unit | Gravity irrigation | Drop irrigation | ||||
---|---|---|---|---|---|---|---|---|---|
CI | Suitability class | CI | Suitability class | CI | Suitability class | CI | Suitability class | ||
1 | 3.27 | N2 | 3.52 | N2 | 20 | 9.36 | N2 | 10.23 | N2 |
2 | 7.48 | N2 | 9.50 | N2 | 21 | 4.68 | N2 | 5.11 | N2 |
3 | 3.27 | N2 | 3.52 | N2 | 22 | 4.68 | N2 | 5.11 | N2 |
4 | 23.30 | N2 | 28.20 | N2 | 23 | 3.27 | N2 | 1.80 | N2 |
5 | 3.27 | N2 | 3.52 | N2 | 24 | 5.46 | N2 | 2.86 | N2 |
6 | 10.92 | N2 | 9.55 | N2 | 25 | 6.17 | N2 | 56.90 | S3 |
7 | 6.48 | N2 | 64.00 | S2 | 26 | 3.78 | N2 | 50.50 | S3 |
8 | 2.80 | N2 | 3.78 | N2 | 27 | 5.76 | N2 | 56.00 | S3 |
9 | 3.27 | N2 | 3.52 | N2 | 28 | 3.24 | N2 | 31.50 | N1 |
10 | 3.27 | N2 | 3.52 | N2 | 29 | 0.76 | N2 | 16.06 | N2 |
11 | 5.46 | N2 | 5.88 | N2 | 30 | 5.18 | N2 | 25.20 | N2 |
12 | 4.68 | N2 | 59.50 | S2 | 31 | 2.80 | N2 | 3.78 | N2 |
13 | 4.16 | N2 | 57.80 | S3 | 32 | 4.68 | N2 | 6.30 | N2 |
14 | 2.10 | N2 | 1.80 | N2 | 33 | 2.80 | N2 | 3.78 | N2 |
15 | 2.10 | N2 | 2.26 | N2 | 34 | 30.12 | N1 | 35.28 | N1 |
16 | 3.27 | N2 | 2.86 | N2 | 35 | 3.27 | N2 | 28.00 | N2 |
17 | 4.21 | N2 | 4.60 | N2 | 36 | 8.73 | N2 | 10.58 | N2 |
18 | 20.40 | N2 | 24.70 | N2 | 37 | 5.46 | N2 | 5.88 | N2 |
19 | 5.46 | N2 | 5.88 | N2 |
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