Variation in biological and physicochemical parameters of the soil affected by uncontrolled landfill sites

Abstract

Defining the biological and physicochemical parameters in soil under illegally dumping sites provides information on the real threat and the direction of changes in the soil environment. The aim of the study was to investigate the effect of uncontrolled dump sites which differed in the composition of the waste deposited on the development of selected groups of soil microorganisms and the activity of redox enzymes and selected physicochemical soil parameters. Additionally, it was verified whether the biological and physicochemical parameters differ in soil depending on the depth (0–20 and 20–40 cm). The research covered three waste landfill sites (W1, W2, W3), the arable field (A) found in the zone of the effect of the dumping site as well as the control point (C). The microbiological analyses show that most amylolytic microorganisms (87.0 × 105 cfu), celullolytic (46.4 × 105 cfu), proteolytic (148.6 × 105 cfu) and bacteria in total (123.2 × 105 cfu) were isolated from the surface later of control soil (C), and definitely least—from the area of dumping sites W1 and W2. The waste accumulated in W1 and W2 led to the soil depletion in organic matter, inhibited the development of microorganisms and their enzymatic activity. The soil under landfill site W3 showed the highest values recorded for physicochemical properties, the count of Actinobacteria, as well as the activity of dehydrogenases and catalase. The concentration of heavy metals in soil under landfill site W3 was even tenfold higher than the values recorded at the other measurement points, which must have been due to the effect of the type of the waste dumped in landfill site W3, where biodegradable waste of organic origin dominated. Disturbing the biological control and unfavourable changes in the microbiocenotic composition were mostly revealed in soil at landfill site W1.