ORGANIC CARBON STOCKS IN A SILTY TEXTURED SOIL FOLLOWING REINTEGRATION OF A 20 YEARS OLD MISCANTHUS×GIGANTEUS SITE INTO A CROP ROTATION  

作　　者：Lisa ESSICH Reiner RUSER Jens HARTUNG Anne HANEMANN Meike GASSNER Liam OBERDORFER Jörn BREUER Jürgen RECKNAGEL Helmut NUßBAUMER Torsten MÜLLER 

机构地区：[1]Institute of Crop Science,Department Fertilization and Soil Matter Dynamics,University of Hohenheim,70599 Stuttgart,Germany [2]Institute of Crop Science,Biostatistics Unit,University of Hohenheim,70599 Stuttgart,Germany [3]Center for Agricultural Technology Augustenberg(LTZ),76227 Karlsruhe,Germany

出　　处：《Frontiers of Agricultural Science and Engineering》2023年第2期183-197,共15页农业科学与工程前沿（英文版）

摘　　要：Miscanthus×giganteus may play an important role in replacing fossil energy resources by bio-based alternatives.One further advantage of miscanthus production is the generally high soil organic carbon(C_(org))enrichment in soils.Due to declining yields,miscanthus stocks are commonly reintegrated into crop rotation after approximately 20 years.Currently there is only few information,whether these high amounts of(C_(org))can be conserved while intensifying soil tillage and crop management after reintegration.Therefore,we monitored(C_(org))stocks in a control with more than 20 years of continuous miscanthus and in a treatment with reintegration of a 20-years old miscanthus stock into an organic crop rotation.Based onδ^(13)C soil values,we calculated an annual(C_(org))enrichment of 0.98 Mg·ha^(-1)·yr^(-1)C under miscanthus.More than 95%of the miscanthus-C was determined in the upper 0.25 m of soil.Continuing miscanthus cultivation did not affect yields during the first five extension years and(C_(org))stocks increased further.Following reintegration,(C_(org))stocks remained constant during five years,which was mainly attributed to the humification and/or stabilization of high amounts of destroyed roots and rhizomes.A significant decrease in(C_(org))(-5.7 Mg·ha^(-1)C)compared to the continuing miscanthus cultivation was at first measured six years after reintegration into crop rotation,underlining the need of long-term investigations.Our data also show,that miscanthus production cycles can be extended in our region,and that sowing of the alfalfa grass mixture after rhizome/root destruction was efficient in preserving(C_(org))stocks for at least first five years after reintegration.

关 键 词：biobased energy crops C balance humus accumulation 

分 类 号：S153.6[农业科学—土壤学]