Soil, litter, and coarse woody debris habitats for arthropods in eastern Oregon and Washington

Arthropods within soil, litter, and coarse woody debris play vital roles in maintaining soil fertility, health, and productivity. Arthropods shred plant material, help mineralize nutrients for plants, act as predators, and serve as food for other wildlife. Some species or groups of species are potentially valuable for monitoring forest health. Natural and human-caused disturbance may immediately kill many arthropods, but changes to habitat structure are likely to cause longer-term effects on their community compositions. Fire effects on arthropods may be minimized if refugia of litter and coarse woody debris are retained. Possible effects of timber harvesting on arthropods include mechanical effects on soil and litter, microclimate changes, and the addition of organic matter to the forest floor. Soil compaction reduces pore size, which may result in loss of habitat and decreased nutrient retention, and changes the microbial and nematode communities, which can affect nutrient cycling and food resources for microarthropods. Thresholds required for healthy ecosystem function, and predictive and decision-support tools that include these components in relation to disturbances are not available.