TY - GEN A1 - Boldt-Burisch, Katja A1 - Schneider, Bernd Uwe A1 - Naeth, M. Anne A1 - Hüttl, Reinhard F. T1 - Root exudation of organic acids of herbaceous pioneer plants and their growth in steriled and non-steriled nutrient-poor, sandy soils from post-mining sites T2 - Pedosphere N2 - Nutrient-poor, sandy soils form the prevailing substrate at post-mining sites and present a challenge for plants. We studied the organic acid quantity and composition of three commonly occurring pioneer plant species, the legumes Lotus corniculatus L. and Trifolium arvense L. and the grass Calamagrostis epigeios (L.) Roth, to determine if plant growth and exudation differed with (nonsterile soil) and without (sterile soil) an indigenous soil microbial community. We investigated whether organic acids were found in the rhizosphere and surrounding soil and whether this influenced nutrient mobilization. This study consists of linked field investigations and a greenhouse experiment. Plants were grown in the greenhouse in either steriled or non-steriled sandy soil from a reclamation site in the Lusatian mining landscape (Welzow S¨ud, East Germany). After seven months, the plant biomass, root morphology, organic acids, and water-soluble nutrients and root colonization with arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) were analyzed. Roots of all three plants in the field and greenhouse experiments were highly colonized with AMF. Calamagrostis epigeios and T. arvense had a significantly higher colonization frequency with DSE than L. corniculatus. The quantity and composition of organic acids strongly differed among plant species, with the highest number of organic acids found for L. corniculatus and lowest for C. epigeios. The quantity of organic acids was greatly reduced in all plants under steriled soil conditions. However, the composition of organic acids and plant growth in steriled soil were reduced for both legumes, but not for C. epigeios, which had a higher biomass under steriled conditions. Changes in nutrient concentrations in the field rhizosphere soil relative to those in the control were measurable after seven months. While the spectrum of organic acids and the growth of legumes seemed to be dependent on a highly diverse soil microbial community and a symbiotic partner, the grass C. epigeios appeared capable of mobilizing enough nutrients without an indigenous microbial community, and might be more competitive on sites where soil microbial diversity and activity are low. Y1 - 2019 U6 - https://doi.org/10.1016/S1002-0160(18)60056-6 SN - 1002-0160 VL - 29 IS - 1 SP - 34 EP - 44 ER - TY - GEN A1 - Boldt-Burisch, Katja A1 - Naeth, M. Anne A1 - Schneider, Bernd Uwe A1 - Hüttl, Reinhard F. T1 - Linkage between root system development of three pioneer plant species and soil nitrogen during the initial phase of ecosystem development of the artificial watershed Hühnerwasser T2 - Geophysical Research Abstracts N2 - ln 2005, a 7-ha artificial watershed (Hühnerwasser) was built an a post mined Iandscape in Lusatia, Germany from sandy Substrates of Pleistocene origin, commonly used in reclamation. The watershed was developed to investigate the initial phase of soil and ecosystem development under natural conditions. At this early stage, nutrients in young sandy soils are limited and pioneer plants become key components of natural succession. Local abundant pioneering legumes Lotus corniculatus and Trifolium arvense and one pioneer grass species Calamagrostis epigeios were investigated 5 years after watershed construction. ln the present study, we investigated the influence of spatial root distribution of these species an soil nitrogen accumulation and on nutrient redistribution. Soil, including roots, was sampled from field monoliths covered with the aforementioned plant species. Root systems of both legumes were mainly restricted to the upper 20 cm of soil, whereas roots of C. epigeios also developed strongly at greater depths. A positive relationship was found, with higher plant densities associated with higher root densities, which were related with higher nodule densities for legumes and which were all associated with significantly higher soil nitrogen concentration relative to non-vegetated areas. This research provides rare information on the role root systems of pioneer legumes play in soil nitrogen input and development of nutrient patterns in the early stage of soil and ecosystem development during revegetation by natural succession. Y1 - 2019 UR - https://meetingorganizer.copernicus.org/EGU2019/EGU2019-5362.pdf VL - 21 ER - TY - GEN A1 - Boldt-Burisch, Katja A1 - Naeth, M. Anne T1 - Phosphogypsum significantly alters root growth and fungal colonization of smooth brome and sheep fescue on a reclamation site T2 - Rhizosphere N2 - Phosphogypsum (PG) is a by-product of phosphate fertilizer production. This study is the first to investigate Bromis inermis and Festuca ovina root morphology and colonization with arbuscular mycorrhizal fungi and dark septate endophytes (DSE) in pure PG and PG with a soil cap (soil). Root length density was significantly lower for plants on PG than on soil and both plant species were colonized with AMF and DSE, with lower frequency and intensity in PG. Phosphorus (20 times), calcium (35 times) and sulphur (50 times) were significantly higher in PG than in soil; resulting higher root tissue concentrations were significantly negatively correlated with mycorrhizal colonization for Festuca but not Bromus. Higher fungal colonization of Bromus, especially with DSE known to be prevalent in extreme environments, may be responsible for its better performance on PG relative to Festuca. Y1 - 2019 U6 - https://doi.org/10.1016/j.rhisph.2018.12.003 SN - 2452-2198 VL - 9 SP - 106 EP - 109 ER -