Poor soil quality can be improved by: adding phosphorous planting legumes killing bacteria all of the above

adding phosphorous, planting legumes

The concentration of organic phosphorus remains very low. A phosphorus can be added in the soil by fertilizers, animal manure and organic matter. It increases the fertility of the soil. Planting legumes can also, improve the soil quality, as legumes trap the atmospheric nitrogen with the help of soil bacteria. Both nitrogen and phosphorus are necessary for plant growth. Killing bacteria will not improve the soil quality as these bacteria will help in decomposition of the organic matter present in the soil, which results in the liberation of essential minerals like phosphorus, carbon and others in the soil, making it more fertile.

thats a little if u want the answer just look it up on google thats what i do haha : )

the answer to this question is 3.