Perennial Roots: A Key Driver to Ecosystem Stability and Long Term Yield.

Annually harvested, unfertilized perennial systems can sustain long-term yields while also maintaining ecosystem services. How do grasslands maintain long term productivity without mining soil carbon or reducing above/belowground diversity? This study investigates the massive, persistent perennial root systems that may sustain this productive system. Root biomass and length, soil carbon, soil nitrogen, microbial biomass, nematode and micro-arthropod communities were measured in four paired perennial grassland and cropland wheat (Triticum aestivum) sites as well as a grassland site that had been converted using no tillage to cropland five years prior in North Central Kansas. Perennial grassland had three to seven times larger root biomass and two times greater root length than croplands. Larger, deeper roots systems were significantly correlated to improved soil physical and biological properties in perennial grasslands.