BonaRes SIGNAL, Site: Mariensee and Reiffenhausen, plant nutrient availability (N,P,K,Ca,Mg), Nutrient response efficiency (N,P,K,Ca,Mg), Nutrient uptake (N,P,K,Ca,Mg), Nutrient uptake and use efficiency (N,P,K,Ca,Mg)

This data was collected in grassland agroforestry (=alley cropping of willow strips and grassland strips) at Reiffenhausen/Germany ((Salix schwerinii x S. viminalis) x S. viminalis and grass-clover mixture) and Mariensee/Germany (S. schwerinii x S. viminalis and grassland mixture consisting of Lolium perenne, Festuca pratensis, Phleum pratense, Poa pratensis) during 2016. Data was taken at 3 replicates (Mariensee)/ 4 replicates (Reiffenhausen) each in the tree strip component (=Tree) of agroforestry, the grassland component of agroforestry at different distances from the tree strip (1m, 4m, 7m) and at the conventional grassland (=Conv) adjacent to grassland agroforestry. Components of agroforestry were also weighted according to their field size representation (=AF_weight Reiffenhausen: Tree 0.46, 1m 0.31, 4m 0.23; Mariensee Tree 0.35, 1m 0.23, 4m 0.21, 7m 0.21). We measured plant-available nitrogen with the buried bag method (Page et al. 1994 Methods of soil analysis), plant-available phosphorus with resin+bicarbonate extraction (Cross and Schlesinger 1995 Geoderma), plant-available Ca, Mg, K by percolation of soil with unbuffered 1 mol L-1 NH4Cl followed by analysis of percolate with inductively coupled plasma-atomic emission spectrometer (ICP-AES; iCAP 6300 Duo VIEW ICP Spectrometer, Thermo Fischer Scientific GmbH, Dreieich, Germany), nutrient response efficiency (NRE) as productivity divided by plant available nutrient (Bridgham et al. 1995 American Naturalist; productivity data provided by Malec et al. for Reiffenhausen and Swieter et al for Mariensee). Plant uptake was calculated as productivity x plant nutrient concentrations (C/N analyzer (Elementar Vario El; Elementar Analysis Systems GmbH, Hanau, Germany) or ICP); Nutrient uptake efficiency as nutrient uptake (productivity x plant nutrient concentrations) / available nutrient; Nutrient use efficiency as productivity/ plant nutrient uptake (productivity x plant nutrient concentrations).