+----------------------+-----------+--------------------------------+ | | |Approximate Weight per Acre of--| | | +---------+----------+-----------+ | | Numbers | Living |Dry Matter| Nitrogen | | | per Gram | Organ- |in Organ- | in Organ- | | | of Soil. | isms. | isms. | isms. | +----------------------+-----------+---------+----------+-----------+ |_Bacteria_-- | | lb. | lb. | lb. | | High level |45,000,000 | 50} | 2 | 0·2 | | Low level |22,500,000 | 25} | | | |_Protozoa_-- | | | | | | _Ciliates_-- | | | | | | High level | 1,000 | -- | -- | -- | | Low level | 100 | -- | -- | -- | | _Amœbæ_-- | | | | | | High level | 280,000 | 320} | 12 | 1·2 | | Low level | 150,000 | 170} | | | | _Flagellates_-- | | | | | | High level | 770,000 | 190} | 7 | 0·7 | | Low level | 350,000 | 85} | | | | _Algæ_ | | | | | | (not blue-green)| [100,000]| 125 | 6 | 0·6 | | Blue-green | Not known.| | Say 6 | Say 0·6 | | _Fungi_-- | | | | | | High level |[1,500,000]| 1700} | 60 | 6·0 | | Low level | [700,000]| 800} | | | | | | +----------+-----------+ | | | | 93 | 9·3 | | | | |= 4 parts nitrogen per| | | | |1,000,000 of soil. | +----------------------+-----------+---------+----------------------+