Returning wheat straw to the field in a non-uniform way can harm the growth of direct-sown rice. When straw is piled up in some areas, it can create too many harmful substances that make it hard for rice seedlings to grow. This can affect the growth of rice plants at the beginning. To fix this, it's important to manage water and soil well by alternating between watering and draining. It's also helpful to transplant rice seedlings early on to make up for any damage caused by too much straw.