| 摘要 |
For establishing the nitrogen, available for plants, in soils and considering it for nitrogen fertilising during the growing period and for detecting special harmful organisms, it is necessary to take soil samples in early spring from three different depths (0-30 cm, 30-60 cm and 60-90 cm). The apparatus, which is fitted on a tractor, has two bore screws which pre-drill the soil for the sampling depths of 30-60 cm and 69-90 cm to a depth of 30 and 60 cm, respectively. No pre-drilling is necessary for the sampling depth of 0-30 cm. In the hollow spindles of the two bore screws and in a short connection stub there is located in each case one tube which, by extending together, each receive the earth from the three soil layers and, by retracting the tubes, owing to the counter-pressure of fixed bars, these are emptied separately into three buckets.
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