62
6.3.2. SRI Area Development
Lands paddy fields with technical irrigation are suitable for applying SRI method or technique. This is because this technique requires good water
management where the availability of water at any time is important although less water is needed. Therefore, only the land or ‘sawah’ with technical irrigation was
used in planning the SRI area development. The available data of land with technical irrigation from the local bureau of statistics indicates that there is a
tendency of decreasing from year to year Table 6.5. One possible cause is the conversion of land-use function from farming land to real estate and others.
Table 6.5. Land paddy fields with technical irrigation in the District of Sukabumi
Year Land with Technical Irrigation ha
2003 5790
2004 5159
2005 5159
2006 3630
2007 3746
2008 3867
Source: BPS Kabupaten Sukabumi 2006-20009
Based on the data in Table 6.5, the trend of the decreasing land area with technical irrigation from 2003 through 2020 was predicted using the Verhulst
model Equation 6.1. The result of the prediction is presented in Table 6.6 which indicates the prediction has an error of 892 and R values of 0.9119. The result of
the detail calculation data is presented in Appendix 6.2. The result of the prediction indicated that the available irrigated land in
2020 would be about a little bit more than 2789 ha as depicted in Table 6.6. This was the maximum available technically irrigated land area possibly to be used for
SRI farming method. It meant that the potential SRI area development planned from 2003 through 2020 was started from zero and end up to about 2789 ha.
Based on the social factor previously discussed and other technical factors, it was assumed that the accumulation of land area development was in the form of non-
linear or polynomial curve, rather than linear one.
63
Table 6.6. Trend of change of paddy field area with technical irrigation
Year Data
ha Verhulst Parameters
Values
2003 5790
5790 γ
0.100 2004
5159 5145 Po
5,790 2005
5159 4674
P∞ 2,500
2006 3630
4317 Error 892
2007 3746
4038 R 0.9119
2008 3867
3814 2009
3632 2010
3482 2011
3357 2012
3251 2013
3160 2014
3083 2015
3016 2016
2958 2017
2907 2018
2862 2019
2823 2020
2789
Figure 6.1 depicts the trend of the decreasing area of land with technical irrigation and possible SRI land area development from 2003 through 2020. The
possible SRI land area development curve illustrates the cumulative land area development with an increasing rate, which is a normal trend in the real world.
Using the SRI development curve of Figure 6.1, the cumulative land area data can be calculated. The land area data for the predicted available land with technical
irrigation and the area of SRI land development are presented in Table 6.7. From the calculated SRI development area data Table 6.7, the required
organic fertilizer can be determined based on the amount of fertilizer required per hectare of organic rice farmed. Table 6.8 presents the results of the calculation of
available and required organic fertilizer. The required fertilizer used in the calculation is based on application of 10 tonha of compost made from animal
wastes and paddy straw. As stated in the previous section, the calculated compost production only used 50 of the available animal beef and dairy cattle wastes
with 65 rendement. Production of cattle manures was based on the capacity of 4.4 tonheadyear. The calculation of paddy straw compost used straw production
of 1.4 times the paddy yield per hectare with 60 rendement.
64
Available Technical Irrigated Land and SRI Development
y = 9.6321x
2
- 38585x + 4E+07 y = 13.219x
2
- 53330x + 5E+07
- 1,000
2,000 3,000
4,000 5,000
6,000 7,000
2002 2004
2006 2008
2010 2012
2014 2016
2018 2020
2022
Year L
a n
d A
re a
h a
Available Technical Irrigated Land Area SRI Land Area Development
Field Data Trend of SRI Land Area Development
Trend of Available Technical Irrigated Land Area
Figure 6.1.
Trend of the decreasing area of land with technical irrigation upper curve and the possible SRI land area development lower curve
from 2003 through 2020 in the District of Sukabumi
Data from Table 6.8 can be used to illustrate the supply and demand of organic fertilizer for SRI Rice farming. In other words, it can be seen how is the
sustainability of SRI organic rice farming in the District of Sukabumi in the sense that the supply always higher than the demand each year. Figure 6.2 illustrates
further the supply and demand of compost each year. The supply of compost from animal wastes can be increased with the utilization of other sources of organic
fertilizers such as household and industrial organic wastes and of course the wastes of other small and medium size of animal as can be seen in Table 6.4.
65
Table 6.7. Data of land paddy field with technical irrigation
Year Trend of Predicted Available Irrigated Land Area
Developed SRI Land Area ha
ha 2003
5790 2004
5145 10
2005 4674
40 2006
4317 89
2007 4038
157 2008
3814 245
2009 3632
352 2010
3482 478
2011 3357
623 2012
3251 787
2013 3160
971 2014
3083 1174
2015 3016
1397 2016
2958 1638
2017 2907
1899 2018
2862 2179
2019 2823
2479 2020
2789 2797
Table 6.8. Results of the calculation of available and required organic fertilizer
Yea r
Crop .
Area ha
Prod. tonha
Available Organic Fertlizer Total
Supply ton
Total Deman
d ton Straw
ton Comp.
ton AOW
ton Comp.
ton
2003 - - -
- 169276.9
60939.7 60939.7
- 2004
21 4.0
41.7 25.0
173011.6 62284.2
62309.2 208.7
2005 80
4.0 160.5
96.3 176758.1
63632.9 63729.2
802.7 2006
178 6.2
552.4 331.4
180504.6 64981.7
65313.1 1782.0
2007 315
8.7 1368.7
821.2 184245.2
66328.3 67149.5
3146.5 2008
490 9.9
2423.7 1454.2
187979.9 67672.8
69127.0 4896.4
2009 703
10.2 3586.1
2151.6 191702.8
69013.0 71164.6
7031.5 2010
955 10.4
4967.0 2980.2
195413.9 70349.0
73329.2 9551.9
2011 1246
10.4 6478.0
3886.8 199107.3
71678.6 75565.4
12457.6 2012
1575 10.4
8189.3 4913.6
202783.0 73001.9
77915.4 15748.6
2013 1942
10.4 10100.9 6060.6
206441.0 74318.8
80379.3 19424.8
2014 2349
10.4 12212.9 7327.8
210063.6 75622.9
82950.6 23486.4
2015 2793
10.4 14525.3 8715.2
213662.6 76918.5
85633.7 27933.2
2016 3277
10.4 17038.0 10222.8
217232.1 78203.6
88426.3 32765.3
2017 3798
10.4 19751.0 11850.6
220766.2 79475.8
91326.4 37982.7
2018 4359
10.4 22664.4 13598.6
224264.9 80735.4
94334.0 43585.4
2019 4957
10.4 25778.2 15466.9
227722.3 81980.0
97446.9 49573.4
2020 5595
10.4 29092.2 17455.3
231138.4 83209.8
100665.2 55946.6
66
ORGANIC FERTILIZER COMPOST
- 10,000
20,000 30,000
40,000 50,000
60,000 70,000
2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
Year A
m o
u n
t t
o n
Total Demand Total Supply
Figure 6.2. Supply and demand of compost each year
6.4. Conclusion