References
- Balfour , E. B. 1975 . The Living Soil and the Haughley Experiment London , U.K. : New and revised edn. Faber .
- Baligar , V. C. 1985 . Potassium uptake by plants, as characterized by root density, species and K/Rb ratio . Plant and Soil , 85 : 43 – 53 .
- Cannell , M. G.R. , van Noordwijk , M. and Ong , C. K. 1996 . The central agroforestry hypothesis: The trees must acquire resources that the crop would not otherwise acquire . Agroforestry Systems , 34 : 27 – 31 .
- Evans , P. S. 1978 . Plant root distribution and water use patterns of some pasture and crop species . New Zealand Journal of Agricultural Research , 21 : 261 – 265 .
- Fergus , I. F. and Martin , A. E. 1974 . Studies on potassium. 4. Interspecific differences in the uptake of non-exchangeable potassium . Australian Journal of Soil Research , 12 : 147 – 158 .
- Fitter , A. H. 1986 . Spatial and temporal patterns of root activity in a species-rich alluvial grassland . Oecologia , 69 : 594 – 599 .
- Fox , R. L. and Lipps , R. C. 1960 . Distribution and activity of roots in relation to soil properties . 7th International Congress of Soil Science , 4 : 260 – 267 .
- Fox , R. L. and Lipps , R. C. 1964 . A comparison of stable strontium and P32 as tracers for estimating alfalfa root activity . Plant and Soil , 20 : 337 – 350 .
- Haak , E. 1978 . Studies on cereal root development and mineral uptake, B: Uptake of calcium, phosphorus and potassium from the plough layer and the subsoil—field experiments , SLU-IRB- 44 Uppsala , , Sweden : Swedish University of Agricultural Sciences .
- Hinsinger , P. and Jaillard , B. 1993 . Root-induced release of interlayer potassium and vermiculization of phlogopite as related to potassium depletion in the rhizosphere of ryegrass . Journal of Soil Science , 44 : 525 – 534 .
- Kuhlmann , H. 1990 . Importance of the subsoil for the potassium nutrition of crops . Plant and Soil , 127 : 129 – 136 .
- Kuhlmann , H. , Ciaassen , N. and Wehrmann , J. 1985 . A method for determining the K-uptake from subsoil by plants . Plant and Soil , 83 : 449 – 452 .
- Kutschera , L. 1960 . Wurzelatlas mitteleuropäischer Ackerkräuter und Kulturpflanzen Frankfurt am Main , , Germany : DLG-Verlag GmbH .
- Lee , R. and Metson , A. J. 1977 . Potassium removal from soil by luceme over three years old and the effect of potassium topdressing . New Zealand Journal of Agricultural Research , 20 : 185192
- Memon , Y. M. , Fergus , I. F. , Hughes , J. D. and Page , D. W. 1988 . Utilization of non-exchangeable soil potassium in relation to soil type, plant species and stage of growth . Australian Journal of Soil Research , 26 : 489 – 496 .
- Ozanne , P. G. , Asher , C. J. and Kirton , D. J. 1965 . Root distribution in a deep sand and its relationship to the uptake of added potassium by pasture plants . Australian Journal of Agricultural Research , 16 : 785 – 800 .
- Peterson , L. A. and Smith , D. 1973 . Recovery of K2SO4 by alfalfa after placement at different depths in a low fertility soil . Agronomy Journal , 65 : 769 – 772 .
- Peterson , L. A. , Smith , D. and Krueger , A. 1983 . Quantitative recovery by alfalfa with time of K placed at different soil depths for two soil types . Agronomy Journal , 75 : 25 – 30 .
- Rodríguez-Navarro , A. 2000 . Potassium transport in fungi and plants . Biochimica et Biophysica Acta , 1469 : 1 – 30 .
- StatSoft . 2000 . STATISTICA for Windows [Computer Program Manual] Tulsa , , U.S.A. : StatSoft, Inc. .
- Steffens , D. and Mengel , K. 1979 . Comparison of the uptake potential of Lolium perenne, Trifolium pratense for the interlayer potassium of clay minerals . Landwirtschaftliche Forschung Sonderheft , 36 : 120 – 127 .
- Tributh , H. , Boguslawski , E. V. , Lieres , A. V. , Steffens , D. and Mengel , K. 1987 . Effect of potassium removal by crops on transformation of illitic clay minerals. Soil . Science , 143 : 404 – 409 .