Abstract
Site-specific liming helps increase efficiency in agricultural production. For adequate determination of the lime demand, a combination of apparent soil electrical conductivity (ECa) and topsoil pH can be used. Here, it was hypothesized that this can also be done at low-input level. Field measurements using the EM38 MK I (Geonics, Canada) were conducted on three experimental sites in north Germany in 2011. The topsoil pH was measured based on two approaches: on the field using a handheld pH meter (Spectrum-Technologies Ltd., Bridgend, UK) with a flat electrode (in situ), and in the lab using standard equipment (ex situ). Both soil ECa (0.4–35.9 mS m−1) and pH (5.13–7.41) were heterogeneously distributed across the sites. The same was true of the lime demand (−1.35–4.18 Mg ha−1). There was a significant correlation between in situ and ex situ determined topsoil pH (r = 0.89; p < 0.0001). This correlation was further improved through non-linear regression (r = 0.92; p < 0.0001). Thus, in situ topsoil pH was found suitable for map-overlay with ECa to determine the site-specific lime demand. Consequently, the hypothesis could be confirmed: The combined use of data from EM38 and handheld pH meters is a promising low-input approach that may help implement site-specific liming in developing countries.
Highlights
Liming, the application of finely ground limestone or CaCO3, is an indispensable practice for maintaining productivity on arable lands in humid climate zones due to soil acidification following permanent leaching of carbonate fractions [1,2]
The average electrical conductivity (ECa) values of the sites ranged from 2.6 mS m−1 (Bremerskamp) to 17.9 mS m−1 (Suchsdorf) (Table 3) (Figure A2)
The distribution of ECa values was higher at both Hochwollhagen and Suchsdorf compared with Bremerskamp (Table 3)
Summary
The application of finely ground limestone or CaCO3 , is an indispensable practice for maintaining productivity on arable lands in humid climate zones due to soil acidification following permanent leaching of carbonate fractions [1,2]. It helps to ensure long-term soil fertility and improves the growth conditions for arable crops, including pastures and grassland regimes with a lower pH threshold than for arable crops. Further costs arise from both the transport of the lime to the field and its application on the field [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
