Does cement make flower pots affect the pH of the soil?

The direction of later use of construction sites is rarely agricultural farming, so the proposition is not valid.
The situation you mentioned mainly exists in highway projects, such as soil removal yard, construction site and construction access road. The main impact is the destruction of surface vegetation, which is easy to cause soil erosion and so on. In accordance with the requirements of water and soil conservation, for the types of land occupied by paddy fields, dry land, etc., it should be restored to cultivated land as much as possible in the later stage and returned to the local use. Therefore, for the construction site, before construction, the occupied land should be stripped of the topsoil (usually about 30cm), piled up in the empty space and sowed with grass seeds to prevent soil erosion. Drainage ditches should be dug around the construction site, and a sedimentation basin should be set up at the outlet. After the construction is completed, the hardened layer should be removed and the topsoil should be returned for greening or re-cultivation.
If no measures are taken, the effects of soil erosion and vegetation destruction are the most intuitive effects. Wastewater during the construction period will cause the soil to harden or compact, reduce water retention, and make the land lose its farming value or reduce agricultural production.
After the construction unit takes certain measures, it can control soil erosion and related impacts. And after the measures are taken, the impact on the soil does not belong to the scope of sewage discharge, so there is no problem of sewage charges in the soil.
Building construction sewage charges should mainly exist in the solid waste discharge link such as construction waste.

jzw0057 Hand Carved concrete flower pot