Building a Tool for Microclimate Management – TheWaterChannel
Jun 21 2021
Climate change threats and fragile ecosystems are threatening agricultural production and resulting in lower agricultural capacity.
This highlights the importance of building climate resilience and improving conditions for better agricultural yield. Increasing climate resilience at a farm level can be done by microclimate management. As was highlighted in an earlier piece, the management of microclimates is a powerful but not well understood frontier in smoothening out the impact of climate change and creating more resilient agricultural ecosystems. This blog will pick up the baton and explore how microclimate management can be made practical in the form of an assessment tool.
Microclimates are the local interplays between several factors: solar radiation, soil moisture, soil temperature, air temperature, air humidity, and wind direction and speed. These microclimatic interplays occur on a small scale with a horizontal range between centimetres and a hundred meters and a vertical range between centimetres and ten meters from the ground; or determined by the canopy boundary layer. Microclimates are thus the conditions in which crops grow, making them an essential factor in agriculture. Due to the high local variability in different soil types, surface slope and orientation, and vegetation cover, this microclimatic scale is highly variable. This high variability differentiates the microclimate from the macroclimate just a few meters above, where atmospheric mixing processes are more active, leading to more moderate and stable conditions. On this higher level, climatic conditions are more challenging to control, and there is only a slight chance for humans to modify this climate. However, unlike this macroclimate, microclimates can be managed. Focusing on a microclimatic scale of a small plot or a single planting mound brings the climate back to more manageable levels. This can be done by making changes in a landscape. Certain land and water management interventions on a site affect the microclimate and, if done right, can improve it. As the microclimate is the scale on which plants grow, modifying the microclimate can improve the plant growth conditions. Improving the microclimate on a farm level can increase crop production and land productivity by enhancing the agricultural ecosystem resilience.
Water conservation practices, such as trenches and ridge-furrow planting, are examples of interventions on a site that can improve the microclimate. By increasing the soil moisture, the evaporation from a site is enhanced. This enhanced evaporation means that more energy will be used in the latent heat fluxes and less in the sensible heat fluxes. Since the sensible heat fluxes contribute to the air temperature, less sensible heat flux will contribute to lower air temperatures. The uptake of latent heat due to the available soil moisture provides an additional daytime cooling effect on a site.