Final answer:
Soil can be dry after tilling due to increased aeration and water evaporation. The water potential is lower in dry soil, leading to moisture loss, and tillage can increase organic matter decomposition which further dries out the soil. No-till farming is recommended to conserve soil moisture and benefit broader ecological goals.
Step-by-step explanation:
Some soil can be very dry after tilling due to the disruption of soil structure, which can lead to increased aeration and water loss. When soil is tilled, larger pores are created, allowing gravity to pull out more water, especially from sandy soil which has larger pores compared to clay soil. The water potential of soil dictates how it retains moisture; dry soil has a lower water potential than wet soil, meaning water moves from areas of higher water potential (wet soil or the plant) to areas of lower water potential (dry soil). Additionally, tilled soil can suffer from rapid decomposition of organic matter, contributing to the loss of soil moisture. According to conservation agriculture practices like no-till farming, it is advisable to minimize soil disturbance to prevent loss of soil moisture, which helps sustain local ecosystems and avoids global warming effects from the release of greenhouse gases.