Table 3.

Monthly mean, maximum, and minimum soil temperature measured at 5, 15, and 35 cm soil depth by field measuring station under plastic coverage (PC) and straw coverage (SC) during the sampling period. Values are given as mean with standard deviation (values from 13 May to 8 June are missing due to malfunction of the field measuring station)

Date	Soil depth	PC			SC			ΔT PC-SC (°C)
		Mean temperature (°C)	Max. temperature (°C)	Min. temperature (°C)	Mean temperature (°C)	Max. temperature (°C)	Min. temperature (°C)
Apr. 17	5 cm	12.6 ± 2.9	21.7	5.9	10.5 ± 2.2	16.5	4.5	2.1
	15 cm	12.2 ± 1.7	16.7	7.6	10.8 ± 1.6	14.9	6.3	1.4
	35 cm	12.0 ± 1.1	14.3	9.2	11.1 ± 1.0	13.4	8.5	0.9
May 17	5 cm	13.3 ± 1.9	19.3	9.6	12.2 ± 1.6	16.3	8.5	1.2
	15 cm	12.8 ± 1.1	15.8	10.7	12.2 ± 1.1	15.2	9.8	0.6
	35 cm	12.6 ± 0.6	14.3	11.3	12.2 ± 0.7	14.0	11.0	0.4
Jun. 17	5 cm	20.0 ± 1.9	23.9	15.2	18.6 ± 1.8	22.4	14.3	1.4
	15 cm	19.5 ± 1.4	22.4	16.0	18.5 ± 1.4	21.1	15.2	1.0
	35 cm	19.0 ± 1.1	20.7	16.5	18.2 ± 1.1	19.9	15.8	0.8
Jul. 17	5 cm	19.4 ± 1.8	24.7	16.2	18.7 ± 1.5	22.1	15.8	0.7
	15 cm	19.1 ± 1.3	22.4	16.5	18.6 ± 1.2	21.3	16.3	0.5
	35 cm	18.9 ± 0.9	20.7	17.3	18.5 ± 0.9	20.1	17.0	0.4
Aug. 17	5 cm	19.4 ± 1.5	22.8	16.2	19.0 ± 1.4	21.7	15.7	0.4
	15 cm	19.1 ± 1.1	21.3	16.8	18.8 ± 1.1	20.9	16.5	0.3
	35 cm	19.0 ± 0.8	20.5	17.2	18.7 ± 0.7	20.1	17.0	0.3
Sep. 17	5 cm	15.4 ± 1.8	19.9	11.6	15.0 ± 1.7	19.3	11.5	0.4
	15 cm	15.5 ± 1.7	20.3	12.6	15.2 ± 1.6	19.7	12.4	0.3
	35 cm	16.0 ± 1.6	20.3	13.8	15.7 ± 1.6	19.9	13.5	0.3
Oct. 17	5 cm	12.6 ± 1.4	16.8	7.6	12.5 ± 1.4	16.5	7.0	0.1
	15 cm	12.8 ± 1.2	16.2	8.9	12.7 ± 1.2	15.8	8.4	0.1
	35 cm	13.4 ± 1.0	16.0	10.7	13.2 ± 1.0	15.7	10.2	0.2