Rapid decomposition of maize detritus in agricultural headwater streams

• DOI: 10.1890/07-1876.1
• Publication Date: 2009-02-17T23:41:54Z
• Authors: Natalie A. Griffiths; Jennifer L. Tank; Todd V. Royer; Emma J. Rosi-Mars...; Matt R. Whiles; Catherine P. Cham...; Therese C. Frauen...; Michelle A. Evans...
• Keywords: Detritus

Headwater streams draining agricultural landscapes receive maize leaves ( Zea mays L.) via wind and surface runoff, yet the contribution of detritus to organic‐matter processing in is largely unknown. We quantified decomposition microbial respiration rates on conventional (non‐Bt) genetically engineered (Bt) three low‐order northwestern Indiana, USA. also examined how substrate quality in‐stream nutrient concentrations influenced by comparing red maple Acer rubrum ) nutrient‐rich low‐nutrient forested streams. found significantly higher vs. Thus both elevated status lability (e.g., low carbon‐to‐nitrogen ratio lignin content) result a rapid incorporation into aquatic food web. that Bt had faster rate than non‐Bt maize, while did not differ between maize. Decomposition were negatively affected genetic engineering, perhaps because toxin does adversely affect assemblage involved decomposition. Additionally, shredding caddisflies, which are known have suppressed growth when fed depauperate these streams, likely play major role Overall, conversion native vegetation row‐crop agriculture appears altered quantity, quality, predictability allochthonous carbon inputs headwater with unexplored effects stream ecosystem structure function.