Fine roots

Damage to epicuticular waxes Altered photosynthesis Increased water loss Accumulation of acidic anions Leaching of ions, sugars, etc. Mineral imbalances Altered metabolism Increased susceptibility to winter freezing injury Death of fine roots Destabilization of trees Reduced water/mineral uptake Reduced water uptake Cations leached below roots Accumulation of acidic anions Altered structure/texture Altered microflora Reduced litter decomposition Altered N transformations Solubilization of metal ions... 

However, relatively few studies have included growing plants in their experimental systems. In order to mechanistically understand the effects of pine roots on microbial N transformations rates under conditions of N limitation, l-year-old pine seedlings were transplanted into Plexiglas microcosms (121) and grown for 10-12 months. Seedlings were labeled continuously for 5 days with ambient CO concentration (350 iL L ) with a specific activity of 15.8 MBq g C. Then, soils at 0-2 mm (operationally defined as rhizosphere soil) and >5 mm from surface of pine roots (bulk soil) of different morphology and functional type (coarse woody roots of >2 mm diameter fine roots of <2 mm diameter ... 

One practical aspect of the procedure for monitoring carbon flow following C labeling is the need to separate roots from the soil for analysis. Incomplete removal of roots can lead to an overestimation of rhizodeposition, but overzealous washing of soil may lead to leaching of " C or loss of fine roots. This problem has been examined in detail for wheat and barley, and procedures to correct for these errors have been developed (69). 

Cu2+ 0.482 mg/g soil Indigenous community Scots pine fine root and needle litter 62... 

Remediation with plants requires that the contaminants be in contact with the root zone of the plants. Therefore, root morphology and depth directly affect the depth of soil that can be remediated or the depth of groundwater that can be influenced. A fibrous root system such as that found in grasses has numerous fine roots spread throughout the soil and provides maximum contact with the soil because of the high surface area of the roots. A tap root system (such as in alfalfa) is dominated... 

Missing insulation increased leaching of N and P, possibly due to increased fine root mortality No effect on phosphatase activity or soil extractable P... 

To improve structure Winter rye, for example, with its very extensive fine root system, improves heavy soil by opening up the structure in lighter soil, the roots bind with soil particles, helping them hold water. 

Fungi often grow in symbiotic association with other organisms. Of special importance are the mycorrhizae (fungus roots) formed by colonization of fine roots by beneficial soil fungi. Almost all plants of economic importance form mycorrihizae.104... 

Eeckhaoudt S, Vandeputte D, Van Praag H, et al. 1992. Laser microprobe mass analysis (LAMMA) of aluminum and lead in fine roots and their ectomycorrhizal mantles of Norway spruce (picea abies (1.) karst.). Tree Physiol 10 209-215. 

The fine roots of plants are killed by the urea treatment, presumably due to ammonia toxicity, but recover vigorously and abundantly during the LP (Sagara 1975). This recovery of roots is accompanied by colonization of the hyphae of LP fungi and by formation of ectomycorrhizas if the associated plants are ectomycorrhizal (Sagara 1995). 

Brunner, I., Ruf, M Luscher, P., and Sperisen, C. (2004). Molecular markers reveal extensive intraspecific below-ground overlap of silver fir fine roots. Mol. Ecol. 13, 3595-3600. 

Janssens, I. A., Sampson, D. A., Curiel-Yuste, J., Carrara, A. Ceulemans, R. (2002). The carbon cost of fine root turnover in a Scots pine forest. Forest Ecology and Management, 168, 231-40. 

Foliage, fine-root, woody-tissue and stand respiration in Pinus radiata in relation to nitrogen status. Tree Physiology, 16, 333-44. 

Tierney, G. L. Fahey, T. J. (2002). Fine root turnover in a northern hardwood forest a direct comparison of the radiocarbon and minirhizotron methods. Canadian Journal of Forest Research, 32, 1692-7. 

Upper soil levels. They also show that secondary forests may re-establish deep root systems (6 m deep) within l6 years. They further show that abundant fine roots infected with mycorrhizal fungi characterize the deep roots of secondary forest. These circumstantial data suggest that secondary forests are mining nutrient reserves in deeper soils, but conclusive data are still unavailable. 

Cuevas, E., E. and Medina. 1988. Nutrient dynamics within Amazonian forests. II. Fine root growth, nutrient availability and leaf litter decomposition. Oecologia 76 222-... 

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