El asesoramiento de los ejecutivos de ventas de las A.V.T Mayoristas

Results

Irrigation water inputs varied to a great extent among the monitored cotton fields, from entirely rainfed cultivation to an input of 15’000 m3 _{water per hectare}46_{. Average estimated}

irrigation water application in organic and conventional cotton fields was 3.0 to 3.5 m3

water per kg seed cotton. There was no significant difference in water use between the two systems. However, estimated average irrigation water inputs in organic cotton fields showed a slight tendency47 _{to be higher than in conventional cotton fields, by 17% in 2003}

and by 5% in 2004 (Figure 12 a). On the average, organic and conventional farmers irrigated their cotton fields 4–5 times in both years. There was no significant difference

45 _{The Indian Central Institute for Cotton Research (CICR) recommends 100–120 kg N/ha for} irrigated cotton cultivation.

46 _{Equivalent to 1500 mm precipitation.}

between systems in the average number of irrigation rounds, and the distribution of irrigation frequencies did not exhibit a clearly distinct pattern (Figure 12 b).

Some farmers in the region use drip systems in cotton cultivation. In order to increase the irrigation efficiency, Maikaal bioRe promoted the use of micro-irrigation and supplied drip systems at reduced rates. Accordingly, the use of drip systems was substantially higher in the organic system: in 2003, drip systems were applied in 26% of the organic cotton fields, compared to 12% in conventional farms. In 2004, however, this share dropped to 13%, compared to 7% in conventional farms.

Irrigation water input in cotton cultivation

0 1000 2000 3000 4000 5000

Organic Conv Organic Conv

2003 2004 a) Ir ri ga ti on wa te r (m 3/ ha ) +17% +5%

Irrigation rounds in cotton cultivation

0% 20% 40% 60% 80% 100%

Organic Conv Organic Conv

>10 7 - 9 4 - 6 1 - 3 0 2004 2003 b)

Figure 12: Irrigation in cotton cultivation in organic and conventional cotton fields (Conv) in 2003 and 2004: (a) average irrigation water inputs and (b) frequency of irrigation rounds. Figures above the bars indicate percentage deviation from means of conventional cotton fields. n in 2003: OF: 58, CF: 112; n in 2004: OF: 62, CF: 108. Differences in means were not significant.

Discussion

Irrigated cotton cultivation in the research region consumes large quantities of water and thus contributes to depleting groundwater resources. Our initial hypothesis concerning irrigation was that organic farms apply less irrigation water in cotton, as their soils can take up and store water better due to higher quantities of organic manures applied (section 3.2.1, hypothesis 1.c). However, average irrigation water quantities were not lower in organic cotton fields, but even showed a tendency to be slightly higher. The results therefore do not support this hypothesis. Admittedly, the error in estimating irrigation water quantities based on well depth, pump details and irrigation duration might be quite substantial, as the maintenance condition of the pump and power fluctuations can have substantial impact on pump output. As this error is unlikely to be different in organic and conventional farms, the tendency of organic farms to use more irrigation water nevertheless deserves our attention. One possible reason for the tendency of higher water input in organic cotton fields could be that more water infiltrates in the soil due to better soil structure (higher porosity and increased activity of earth worms). Another likely reason is that shares of wheat in the winter season are lower in organic farms (see section 4.1.1): if cotton is continued after the monsoon season, instead of uprooting it and growing wheat, it requires more irrigation water (fields are not irrigated during the monsoon season).

Interviews with farmers in the region indicated that irrigation water application is mainly determined through the availability of ground or river water and farmers’ access to it,

limited through the availability of wells, pumps and electricity. It appears that even in the case that the crop would require less water, due to better water retention capacity of the soil, farmers use the saved water for increasing the number of irrigation rounds or for irrigating other fields, rather than keeping it in the wells or aquifers. Similarly, the use of a more efficient application technique (drip systems) does not result in actual water saving, but rather in earlier sowing (before the monsoon starts), as the study conducted by IWMI in the research region has shown (Shah, Verma et al., 2005). As the State usually provides electricity for running pumps free of cost, farmers currently have no economic incentive to save water.

It is also doubtful whether farmers always apply irrigation water as per the actual requirement of the crop. As cotton yields are not strongly correlated with estimated irrigation water quantities (see section 4.3.1) it could be that in a number of cases irrigation practices even lead to adverse effects. Too high water application could result in reduced yields due to water logging or stimulation of vegetative growth rather than production of bolls48_{. To compare actual water requirements in organic and conventional cotton farming,}

further studies are needed. In doing so, investigators should accurately measure applied water quantities with the help of water meters and control management practices such as crop shares to a certain extent. Plot trials are likely to be more suitable than on-farm research to tackle this question.

Although organic standards demand that water sources shall be used in a sustainable way (IFOAM, 2005), organic farming does not automatically prevent unsustainable extraction of groundwater. Kooistra and Termorshuizen (2006) therefore demand that organic standards need improvement concerning water use issues. As stricter standards on water use are unlikely to be enforceable and would rather lead to exclusion of irrigated farming from organic certification, we suggest that economic mechanisms and state regulations are more appropriate to improve the sustainability of water use in agriculture.