Makrofaagit

Makrofaagit, also known as macrofauna, are larger organisms that live in soil, sediment, or other substrata. They are typically defined as being greater than about 2 millimetres in size, though some sources use thresholds from 0.5 to 2 millimetres depending on the methodological context and the taxonomic group being studied. This size distinction helps separate macrofauna from smaller soil organisms used in related ecological categories such as mesofauna and microfauna.

Makrofaagit play key roles in ecosystem processes. Through bioturbation they mix and aerate soil, promote soil aggregation, and enhance the distribution of organic matter. They contribute to decomposition and nutrient cycling by fragmenting litter and stimulating microbial activity. They also form parts of food webs, serving as prey for birds, small mammals, and other invertebrates. Because of their sensitivity to soil disturbance and chemical stress, macrofauna are commonly used as bioindicators of soil health and land-use impact.

Typical components of the macrofauna include earthworms, millipedes and centipedes, woodlice and other isopods, snails and slugs, and larger beetles and other soil-inhabiting arthropods. In aquatic sediments macrofauna may include crustaceans such as amphipods and isopods, mollusks, and diverse insect larvae.

Study and sampling of macrofauna rely on methods such as hand sorting of soil and litter, bulk soil cores, sieving, and pitfall traps. Changes in macrofauna communities reflect long-term changes in land management, soil structure, moisture, and contamination.

Overall, makrofaagit represent a diverse and functionally important component of terrestrial and aquatic ecosystems, linking physical soil processes with food webs and biogeochemical cycles.