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Ants and Termites Increase Crop Yield in a Dry Climate

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Ants and Termites Increase Crop Yield in a Dry Climate

Theodore A Evans et al. Nat Commun.

Abstract

Agricultural intensification has increased crop yields, but at high economic and environmental cost. Harnessing ecosystem services of naturally occurring organisms is a cheaper but under-appreciated approach, because the functional roles of organisms are not linked to crop yields, especially outside the northern temperate zone. Ecosystem services in soil come from earthworms in these cooler and wetter latitudes; what may fulfill their functional role in agriculture in warmer and drier habitats, where they are absent, is unproven. Here we show in a field experiment that ants and termites increase wheat yield by 36% from increased soil water infiltration due to their tunnels and improved soil nitrogen. Our results suggest that ants and termites have similar functional roles to earthworms, and that they may provide valuable ecosystem services in dryland agriculture, which may become increasingly important for agricultural sustainability in arid climates.

Figures

Figure 1
Figure 1. Efficacy of exclusion treatment.
Effect was measured as (a) number of active ant nests per plot, pre-exclusion (at sowing May 2006) and post-exclusion (at harvest November 2006); ***P<0.001, n=5 and (b) number of baits contacted by termites post-exclusion (pre-sowing 2008); **P=0.002, n=5. Data are means±standard errors; exclusion plots are squares, control plots are circles, tilled plots are hatched, no-till plots are solid colours.
Figure 2
Figure 2. Crop yield in plots with or without soil insects and tillage.
Yield was measured in 2006, when treatments were applied, and in 2008. (a) Pinched grain as percentage of total weight; ***P<0.001, n=5. (b) Variation from average wheat yield. Data are means±standard errors; exclusion plots are squares, control plots are circles, tilled plots are hatched, no-till plots are solid colours; **P=0.005, n=5.
Figure 3
Figure 3. Tunnel density in soil with or without soil insects and tillage.
Data are mean number of ant and termite tunnels per 100 cm2 (±standard errors) after harvest in 2006 (n=1) and after harvest in 2008 (n=5); **P=0.003. Exclusion plots are squares, control plots are circles, tilled plots are hatched and no-till plots are solid colours.
Figure 4
Figure 4. Soil water content with or without soil insects and tillage.
Soil water content at a depth of 50 cm was measured in plots with or without soil insects and tillage during similar rainfall events. In (a) 2006 (12 mm on 8 September) and (b) 2008 (11 mm on 9 June). Data are means, bars are least significant differences, n=5; **P=0.008. Exclusion plots are squares, control plots are circles, tilled plots are hatched and no-till plots are solid colours.
Figure 5
Figure 5. Total mineral soil nitrogen in plots with or without soil insects and tillage.
Data are means±standard errors measured after harvest in 2006 and after harvest in 2008; n=5, ***P=0.001. Exclusion plots are squares, control plots are circles, tilled plots are hatched and no-till plots are solid colours.

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References

    1. Pimental D. et al. . Food production and the energy crisis. Science 182, 443–449 (1973). - PubMed
    1. Tilman D., Cassman K. G., Matson P. A., Naylor R. & Polasky S. Agricultural sustainability and intensive production practices. Nature 418, 671–677 (2002). - PubMed
    1. Evenson R. E. & Gollin D. Assessing the impact of the green revolution, 1960 to 2000. Science 300, 758–762 (2003). - PubMed
    1. Hassan R., Scholes R. & Ash N. (eds). Ecosystems and Human Well-being: Volume 1, Current State and Trends (Island, 2005).
    1. Foley J. A. et al. . Global consequences of land use. Science 309, 570–574 (2005). - PubMed

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