Journal of the Japanese Society of Revegetation Technology

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Grazing by large ungulates had both acceleration and deceleration effects on primary productivity and nutrient cycling in grassland ecosystems. The directions of these effects can differ among ecosystems because climate is one of the most important determinant. In Mongolian steppe, the ecosystem type is changed with latitudinal gradient of the aridity from forest-steppe in the north to steppe in the middle to gobi-steppe in the south. Our objective was to clarify the effects of livestock grazing on the surface soil chemical properties in three types of Mongolian steppe ecosystems along an aridity gradient. The soil samples (0.10 cm) were taken from inside and outside of the exclosure fence to analyze soil chemical properties and to determine net nitrogen (N) transformation rates for laboratory incubation. The elements essentially for the plants were decreased and net N transformations were decelerated along aridity with increasing soil pH. The effects of grazing were not prominent for the soil nutrient pools. However, the grazing decelerated net N transformation rates, especially drier incubation condition, and increased soil pH. These results suggested that grazing by large ungulates decelerated nutrient cycling, which might caused by increased alkalinity in Mongolian steppe ecosystems.

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We investigated the effect of lime addition to soil (0, 2.0, 3.0, 4.0 ton/ha) on forest soil and the growth and physiological responses of Pinus koraiensis in Ansan industrial complex, South Korea. Three years later, lime addition can also significantly increase soil pH from 4.0 to 4.9, and the soil respiration rate (p<0.05). Phosphorus and Chlorophyll (a+b) content in needles of P. koraiensis was significantly increased with increasing amounts of addition of lime to soil (p<0.05). Moreover, the photosynthetic rate (A/Ci curve and light-photosyn-thesis curve) of P. koraiensis became higher with increasing amounts of addition of lime than that of control. In addition, the shoot length of 3 years old and survival rate of 3 years old needle and stem diameter increased significantly as more lime is added to soil (p<0.05). However, the inoculation rate of ectomycorrhiza inoculated with P. koraiensis was decreased with increasing amounts of addition of lime to soil.

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The unicellular aerial microalga, Elliptochloris reniformis (Chlorophyceae), was isolated from the bark of trees growing on the campus of Kogakuin University in Hachioji, Tokyo, and cultured on the protein ex-tract of jellyfish (Aurelia aurita) caught in Tokyo Bay. Liquid chromatography analysis revealed that the major protein components in the extract were mucin and collagen. Culture of the microalga in a liquid medium containing the jellyfish protein extract for 13 days under light conditions resulted in a six-fold increase in microalgal biomass and a marked decrease in the concentration of the jellyfish proteins in the medium; however, no algal growth was observed in cells cultured in the dark. These findings suggested that the alga used the proteins as a nitrogen source for growth under light conditions. In addition, E. reniformis could be cultured in the presence of protein extract from jellyfish for 49 days under wet or dry conditions on external walls (e.g., mortar). These findings are useful for cultivating microalgae on wall surfaces using a jellyfish protein extract as a growth medium.

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