Slieku (Oligochaeta, Lumbricidae) cenožu izmaiņas uz antropogēno un dabisko faktoru fona

Petijuma ir izverteta slieku (Lumbricidae) bioindikativa nozime augsnes stavokla raksturošana. Slieku blivumu un sugu skaitu nosaka augsnes tips un granulometriskais sastavs. Visaugstakais blivums ir smilšmala augsnes. Blivuma dinamika ir saistita ar meteorologiskajiem apstakliem, vietas orografiju un pielietotajiem agrotehniskajiem pasakumiem. Intensivi kultivetas platibas slieku blivums un sugu daudzveidiba samazinas. Slieku populacijas labi raksturo izmainas oligotrofajas priežu mežu augsnes. Eitrofikacijas rezultata slieku blivums ieverojami pieaug, - paradas jaunas sugas, izmainas sugu cenozes un dominances struktura. Slieku darbiba klust par butisku ekosistemas attistibas iekšejo faktoru. Sliekas uz augsnes izmainam reage atrak ka vegetacija, tadel tam ir ipaša nozime eitrofikacijas sakuma stadiju noteikšana. Atslegas vardi: Lumbricidea, augsnes apstrade, augsnes tips, eitrofihacija, bioindikacijaThe aim of the study was a bioindicative assessment of soil ecosystem condition based on the earthworms (Lumbricidae) abundance and community structure. The total density and species structure of earthworms depends on soil type and granulometry. Most favorable are loamy soils. The dinamics of earthworm community is largely related to such factors as local meteorological conditions, agricultural practice and relief. Intensive tillage negatively affected earthworms and resulted in reduction in number and species diversity. The earthworm populations dynamic well reflect an eutrophication of oligotrophic forest soils with increasing of density, changing of communities and dominance structures. Activity of earthworms can play an important role as one of the major internal factors of biocenosis. Earthworms reacts more rapidly to the changes in soil properties than related local plant communities do it. Thus they can be used as bioindicators in initial stages of eutrophication. Keywords: Lumbricidae, soil tillage, soil type, soil eutrophication, bioindicatio