Linking Drought Indices with Maize Productivity: A Comparative Analysis of SPI and DSI in Temperate Rainfed Agriculture

Why It Matters

Understanding the nuanced drought signals helps policymakers and growers design region‑specific adaptation strategies, protecting maize yields amid climate variability. The combined use of SPI and DSI offers a more reliable early‑warning framework for rain‑fed agriculture.

Key Takeaways

• DSI captures dry spell frequency better than SPI
• Moderate DSI (8‑12) boosts maize yields
• Severe DSI (>20) sharply cuts maize area and output
• All districts show decreasing DSI trends since 1997
• Combined SPI‑DSI approach guides targeted drought adaptation

Pulse Analysis

Rain‑fed, temperate agriculture in Jammu & Kashmir faces a delicate balance between water scarcity and excess. Traditional drought monitoring has relied on the Standardized Precipitation Index, which aggregates monthly rainfall but often misses the timing of moisture deficits that are critical for crop development. The Dry Spell Index, by contrast, quantifies the frequency and length of consecutive dry days, offering a granular view of intra‑seasonal stress that directly impacts maize phenology. Integrating both metrics provides a fuller picture of drought dynamics, enabling more precise risk assessments.

The study’s longitudinal data reveal stark spatial heterogeneity: Baramulla experiences the greatest year‑to‑year variability, while Kupwara and Srinagar endure the highest average drought severity. Intriguingly, moderate drought conditions (DSI scores between 8 and 12) appear to enhance maize productivity, likely by limiting disease pressure and avoiding water‑logging. However, once DSI exceeds 20, yields and cultivated area plummet, underscoring maize’s vulnerability to prolonged moisture deficits. Importantly, all surveyed districts exhibit a downward trend in DSI and an upward trend in SPI, signaling improving rainfall patterns over the past three decades.

These insights have immediate practical implications. Breeding programs can prioritize drought‑tolerant maize varieties calibrated to the identified moderate‑stress sweet spot, while extension services can deploy combined SPI‑DSI dashboards for early‑warning alerts. Water‑management interventions—such as supplemental irrigation during identified dry spells—can be timed more accurately, reducing yield losses. Ultimately, the dual‑index approach equips policymakers with actionable intelligence to craft region‑specific adaptation strategies, bolstering food security in a climate‑sensitive landscape.