Soil organisms provide crucial ecosystem services that support human life. However, little is known about their diversity, distribution, and the threats affecting them. Here, we compiled a global dataset of 60 sampled earthworm communities from over 7000 sites in 56 countries to predict patterns in earthworm diversity, abundance, and biomass. We identify the environmental drivers shaping these patterns. Local species richness and abundance typically peaked at higher latitudes, while biomass peaked in the tropics, patterns opposite to those observed in aboveground organisms. Similar to many aboveground taxa, climate variables were more important in shaping earthworm communities than soil properties or habitat 65 cover. These findings highlight that, while the environmental drivers are similar, conservation strategies to conserve aboveground biodiversity might not be appropriate for earthworm diversity, especially in a changing climate.

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The amount of litter moving down the slope was measured in three types of forest, together with an examination of rain as a factor in bringing this about. The three forest types were a natural mixed stand of Pinus densiflora and hardwood trees (plot A), a Cryptomeria japonica plantation (plot S) and a Chamaecyparis obtusa plantation (plot H). The amount of moved litter was quite large in plots A and H, but relatively small in plot S. The rain factor had little influence on litter movement in plot A, but was the main cause of movement in plot S and (especially) plot H. It is suggested that measurement of litter input and output not only by traps above ground level, but also by ones on the ground is essential for determining the cycling of elements in C. obtusa forests.It is also suggested that the decomposition of leaf litter should be studied both on the soil surface and in the soil in C. obtusa forests.

Decomposition of plant material is an important component in the study of forest ecosystem because of its critical role in nutrient cycling. Different tree species has different nutrient release patterns, which are related to leaf litter quantitative traits and seasonal environmental factors. The quantitative traits of leaf litter are important predictors of decomposition and decomposition rates increase with greater nutrient availability in the forest ecosystems. At the ecosystem level, litter quantitative traits are most often related to the physical and chemical characteristics of the litter, for example, leaf toughness and leaf mass per unit area, and lignin content tannin and total phenolics. Thus, the analysis of litter quantitative traits and decomposition are highly important for the understanding of nutrient cycling in forest ecosystems. By studying the role of litter quantitative traits on decomposition and nutrient cycling in forest ecosystems will provide a valuable insight to how quantitative traits influence ecosystem nutrient dynamics. Such knowledge will contribute to future forest management and conservation practices.

Photoluminescent R~( b p y ) 3~+ complex, electron-accepting methylviologen, and an amino acid residue model compound were dispersed in a polysiloxane film, and photoinduced electron transfer from the excited Ru-( b p~) 3~+ to methylviologen and the effect of amino acid residue model on the electron-transfer distance have been studied. The electron-transfer reaction was analyzed by a static model, and the electron-transfer distance was calculated considering the distance distribution between the nearest neighboring molecules as well as their excluded volume effect. In the absence of the amino acid residue model, the electron-transfer distance was obtained to be 1.4 nm. p-Cresol, a model compound of tyrosine residue, did not affect the electrontransfer distance, but 3-methylindole, a model of tryptophan residue, increased the electron-transfer distance to twice (2.7 nm) that without it.