caa a22 4500 386315973 CHVBK 20180307111605.0 cr unu---uuuuu 161130s1988 xx s 000 0 eng 10.1017/S0889189300002423 doi S0889189300002423 pii (NATIONALLICENCE)cambridge-10.1017/S0889189300002423 Reganold John P. Assistant Professor, Department of Agronomy and Soils, Washington State University, Pullman, WA 99164. Comparison of soil properties as influenced by organic and conventional farming systems [Elektronische Daten] [John P. Reganold] This paper summarizes data from previous and current studies on two adjacent farms, one organically managed and the other conventionally managed, in the Palouse region of eastern Washington. The 320-hectare organic farm has been managed without the use of commercial fertilizers and only limited use of pesticides since the farm was first plowed in 1909. The 525-hectare conventional farm, first cultivated in 1908, began receiving recommended rates of commercial fertilizers and pesticides in 1948 and the early 1950's, respectively. The organically-farmed Naff silt loam soil had significantly higher organic matter, cation exchange capacity, total nitrogen, extractable potassium, water content, pH, polysaccharide content, enzyme levels, and microbial biomass than did the conventionally-farmed Naff soil. Also, the organically-farmed soil had significantly lower modulus of rupture, more granular structure, less hard and more friable consistence, and 16 centimeters more topsoil. This topsail difference between farms was attributed to significantly greater erosion on the conventionally-farmed soil between 1948 and 1985. The difference in erosion rates between farms was most probably due to their different crop rotation systems; Le., only the organic farm included a green manure crop in its rotation, and it had different tillage practices. These studies indicate that, in the long-term, the organic farming system was more effective than the conventional farming system in maintaining the tilth and productivity of the Naff soil and in reducing its loss to erosion. Copyright © Cambridge University Press 1988 organic matter nationallicence cation exchange capacity nationallicence water content nationallicence enzyme levels nationallicence microbial biomass nationallicence erosion nationallicence American Journal of Alternative Agriculture Cambridge University Press 3/4(1988), 144-155 0889-1893 3:4<144 1988 3 AJA https://doi.org/10.1017/S0889189300002423 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0889189300002423 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Reganold John P. Assistant Professor, Department of Agronomy and Soils, Washington State University, Pullman, WA 99164 NATIONALLICENCE 773 0- American Journal of Alternative Agriculture Cambridge University Press 3/4(1988), 144-155 0889-1893 3:4<144 1988 3 AJA CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge