| Abstract: | Seawater-irrigated halophyte systems have been proposed as sites for carbon storage, and therefore the fate of halophyte-derived
carbon in the soil needs to be determined. To evaluate the role of the microfloral and microfaunal communities in soil carbon
cycling of a halophyte agroecosystem, the response to various agronomic practices was investigated. Biomass and activity of
the soil microflora and the abundance and trophic composition of the soil microfauna were determined under three planting
densities of the halophyte Salicornia bigelovii (Chenopodiaceae) in plots with and without incorporated post-harvest halophyte residues. Microbial biomass and activity,
as well as the abundance of nematode grazers, increased in response to the amendment of soil with halophyte residues. The
microbial response to the density and presence of halophyte plants was, however, limited. Microbial activity increased in
response to the presence of plants only after Salicornia had entered senescence, a result suggesting that in the mineral soil where halophytes were cropped, only dead root material
provided a significant amount of microbially available organic matter. Success of halophyte agroecosystems in storing plant-derived
carbon will depend primarily on the management of post-harvest residues and secondarily on the growing practices used prior
to plant senescence.
This revised version was published online in June 2006 with corrections to the Cover Date. |
