Responding to Seasonal Droughts: Practical Adjustments to Improve Irrigation Efficiency

Responding to Seasonal Droughts: Practical Adjustments to Improve Irrigation Efficiency

When facing seasonal droughts, the core objective of improving irrigation efficiency is to maximize the retention of precious water resources in the crop root zone soil and minimize all unnecessary losses. This doesn't require large-scale modifications, but rather fine-tuning existing irrigation practices, field management, and agronomic measures. The key is a shift in mindset from "water delivery" to "water conservation."

Primary Adjustment: Change irrigation time and frequency to reduce evaporation losses.

Adjust watering times to early morning or evening, avoiding the midday period of strong sunlight and wind. At these times, temperatures are lower and wind speeds are lower, significantly reducing water evaporation losses, allowing more water to penetrate the soil.

Adopt a "small amounts, frequent applications" strategy, but ensure thorough watering each time. During drought periods, appropriately increase the frequency of irrigation, but the amount of water each time should be sufficient to moisten the main root zone. This is more beneficial for crop absorption than a single large flood irrigation followed by a long period of drought, and it reduces deep percolation waste. The key is to learn how to determine the standard for "thorough watering" (e.g., achieving the required wetting depth).

Core Adjustment: Improve field irrigation methods to enhance water use precision.

Maximize the use of existing pipelines: Ensure that water is delivered to the fields through pipes rather than open ditches; this is the first step in preventing leakage. Inspect and repair all leaks in pipes and connections.

Promote refined furrow and border irrigation: If using surface irrigation, be sure to properly prepare the furrows and borders, ensuring they are level and of appropriate width and length (the length can be shortened during the dry season), ensuring rapid and even water flow, avoiding localized waterlogging or areas that are not watered.

Upgrade to localized irrigation when conditions permit: In high-value areas such as vegetable gardens and orchards, consider investing in drip irrigation or micro-sprinkler systems. These deliver water directly to the crop roots, resulting in almost no evaporation or runoff losses, making them the most effective means of saving water and increasing efficiency during the dry season, and they can be combined with fertilization.

Key Adjustment: Strengthen field agronomic measures to effectively conserve water. Timely intertillage and soil loosening: After watering or rainfall, perform shallow hoeing when the topsoil is slightly dry. This cuts off soil capillaries, effectively preventing upward evaporation of water from the lower layers – this is the principle behind "water under the hoe."

Use mulching to conserve moisture: Cover the soil between rows or plants with a layer of straw, weeds, plastic film, or weed control fabric. This directly blocks sunlight, lowers soil temperature, reduces evaporation, and inhibits weeds from competing with crops for water. This is a low-cost and highly effective water conservation method.

Adjust planting structure: In long-term planning, consider planting more drought-resistant crop varieties in drought-prone areas to reduce reliance on irrigation from the source.

Management adjustments: Monitor and plan effectively, shifting from a reactive to a proactive approach.

Monitor soil moisture: Do not rely solely on experience or the calendar for watering. Determine the actual water deficit in the crop root zone by squeezing a soil sample (to see if it crumbles) or using a simple soil moisture meter to achieve "on-demand watering" and avoid ineffective irrigation.

Check weather forecasts: Before irrigating, check for recent rainfall to avoid wasting water by irrigating before rain.

Prioritize critical water needs: When water resources are extremely scarce, prioritize water use during the most sensitive growth stages of the crop (such as flowering and fruiting) to ensure a basic yield.

In short, dealing with drought and improving efficiency is a systemic project. Start with daily operations such as adjusting watering times and maintaining irrigation ditches, combine these with agronomic water conservation measures such as intertillage and mulching, and actively move towards piped and localized irrigation methods. Through the combination of these practical adjustments, you can achieve better irrigation results with limited water resources during the dry season and ensure crop growth.