<span>. built dams to provide for irrigation</span> irrigation was used to farm lands that were originally arid and semi arid<span>4. converted bad land into agricultural fields</span> <span>these bad lands otherwise ARID AND SEMI ARID were successful reclaimed through irrigation methods. </span><span></span><span>5. invented new farming methods
</span> improvements in agricultural techniques and tools bolstered the agricultural sector making it one of the important source of taxes for the dynasty.
After the nation was united, the Tang dinasty made strong efforts to mantain it that way, and one of those was to heavily support and fund agriculture, at that time food supply was on of the most important things to keep an empire running, so they developed and constructed dams to provide irrigation, found ways to convert bad land into agricultural fields and invented new farming methods, like soaking the seeds in different compounds very planting them in order for the plantation-growth rate to be more effective, they also initiated to use insecticides and pesticides which increased considerably the harvest.
The environmental legislation signed by President Bush in 1990 set stricter standards on pollution from factories. This was done to prevent the negative results of pollution, since everything concerning that was getting worse and worse.