Abstract
Land management affect soil organisms, and component of soil organisms and their ecological functioning also affect plant growth. Protecting soil biodiversity and biomass is thus important to promote conservation agriculture. Apple cultures in Japan is known its high quality due to culture improvement in varieties and growing managements, However, organic apple farming is very limited. Mr. Akinori Kimura, Hirosaki City, Aomori Prefecture, was successfully growing organic apple by his own management with no-fertilization and no-agrochemicals. Hypothesis to explain the reason of his success has been partly explained, for example, by increase in natural enemies, and by higher diversity and abundance of endophytic fungi in apple leaves. However, any soil characteristic in his orchard has not been reported. We collected multiple samples on September 2014 from three sites: Mr. Kimura’s apple orchard, adjacent conventional managed apple orchard and adjacent secondary natural forest. We examined soil physicochemical properties (total C, N, exchangeable P and K, pore space, pH), microbial biomass (PLFA/NLFA), soil microarthropods and soil macrofauna. The organic orchard showed intermitted values on soil chemical and physical parameters except that K showed the lowest value. Biomass of AMF, microarthropods and macrofauna were the highest in the organic orchard, especially oribatid mites were 10 times more than the conventional orchard. Higher accumulation of litter and weed biomass together with higher soil pore space seemed to increase diversity and biomass of soil organisms. These changes would induce higher recycling of plant nutrients, higher detrital infusion from soil to aboveground. The management of apple orchard by Mr. Kimura can expect the higher soil ecological functioning by promoting biodiversity and biomass of soil organisms.
