Freezing–thawing effects on phosphorus leaching from catch crops

Management Options for an Efficient Utilization of Phosphorus in Agroecosystems

“…Catch cropping may help to reduce nutrient losses, since erosion is significantly reduced when the soil is thoroughly covered by crops, and nutrients can be temporarily fixed biologically by catch crops. On the other hand, an experiment with shallow soil lysimeters (0.25 m deep) showed, that after freezing-thawing cycles, P concentrations in the leachate in the lysimeters with ryegrass, oilseed radish and red clover were higher than in the control without a catch crop (Li et al 2014). Probably, these high P concentrations in the upper soil layer were related to the high P uptake (P mobilization) by these crops and following high P release.…”

“…Catch crops are mainly used as green manure and cover the soil in temperate climates from late autumn until the next spring. Using catch crops as green fertilizer can increase cropping system sustainability and soil fertility by enriching organic matter in the soil through plant residues, reducing erosion by soil covering, and holding back nutrients by biological fixation (Li et al 2014;Eichler-Löbermann et al 2008;Nziguheba and Bünemann 2005;Sørensen 1991).…”

Biomass production and phosphorus retention by catch crops on clayey soils in southern and central Sweden

“…The experimental sites were: Brunnby (59 • 36 N, 16 • 39 E), which was used in 2009/2010 (Brunn-9/10); two at Linnés Hammarby (59 • 49 N, 17 • 48 E), in 2010(Linby1-10/11) and 2011; and three at Lanna (58 • 21 N, 13 • 10 E) in south-west Sweden, in 2009/2010 (Lan-9/10), 2010/2011 (Lan-10/11) and 2011/2012 (Lan-11/12). These experimental sites have been used previously for collecting lysimeters for a P leaching study (Liu et al, 2014). All six sites had a clay (<0.002 mm) content of 44-45% and silt (0.002-0.0625 mm) content of 42-52% in the topsoil (0-0.25 m).…”

“…longipinnatus 'Structurator'). Each species was tested at four or six sites except phacelia, which was included only at two sites in 2009/2010 (Table 2), as it was obviously sensitive to frost and thus considered unsuitable for Swedish climate conditions (Liu et al, 2014). Full details of these catch crops, including descriptions on roots, can be found in Liu et al (2013).…”

“…In particular, the P lost from catch crop tissues is a great concern on clayey soils, where the presence of macropores facilitates fast transport of water and P (Riddle and Bergström, 2013). In a laboratory lysimeter study, Liu et al (2014) found that repeated freezing-thawing cycles (FTCs) increased potential P leaching from clay soils with catch crops, in particular from soils with perennial ryegrass and oilseed radish. Therefore, the winter hardness and survival rate of catch crops must be considered when selecting appropriate species to mitigate P losses under conditions such as those in northern Europe (Brandsaeter and Netland, 1999;Brandsaeter et al, 2008).…”