Rhizosphere environment

H. H. Rogers, G. B. Runion, and S. V. Krupa, Plant responses to atmospheric CO, enrichment with emphasis on roots and the rhizosphere. Environ Polhit. 155 (1994). 

The total rhizosphere environment is governed by an interacting trinity of the soil, the plant, and the organisms associated with the root (Lynch, 1990a,b), as illustrated in Figure 1.3. 

The literature shows that many fewer data are available on dissolved than on solid-phase heavy metals at the soil-root interface. To date, several approaches have been used to acquire soil solution samples from the rhizospheric environment, includmg water displacement, water extraction, centrifugation, and microsuction cups. However, because of technical constraints, no single method appears to sample unaltered rhizosphere solution. 

The results from these complementary approaches showed that the rhizospheric environment accelerated the weathering of primary minerals. In situ weathering products contributed to the retention of trace metals at the soil-root interface. The reader is referred to Chapter 2 written by S6guin et al. (2005) for a detailed presentation of the methods used to measure weathering and for a comprehensive discussion of the results gathered as part of this project. 

The objective of the present study is to examine the desorption kinetics of Cd following its adsorption on iron oxides. To simulate the effects of organic ligands in soil rhizosphere environment and chloride-bearing fertilizer, Cd desorption caused by citrate, acetate and chloride was investigated. 

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