Horse waste is rich in phosphorus and also nitrogen compared to normal soil.

和普通土壤相比，马粪更富含磷和氮。

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This will help dry the soil. In normal conditions, placing mulch around rose plants is a good idea.

VOA: special.2010.06.15

The phosphate rock industry there (extracted to use in fertilisers) leaves a waste called phosphogypsum. this is around and about 30 parts per million (ppm, and normal soil is about 3 ppm) uranium and it can most certainly be processed to extract that.

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