Nutrient cycling in plant-soil interaction in reclaimed alder plantations and succession sites after coal mining
Abstrakt
Open-cast mining causes landscape degradation and the aim of reclamation efforts is to restore ecosystems. Production of plant biomass plays the important role for restoration and development of soil and whole functioning ecosystem.
The study was carried out on large post-mining spoil heaps after brown coal mining, in the Sokolov area (Czech Republic). The aims of this study was to compare nutrient composition of plant and tree biomass on spontaneous developed sites with reclaimed sites afforested by alders same age (20 years old).
Study was also focused on nutrient budget in individual biomass compartments and nutrient cycling in plant soil interaction. Data about soil, throughfall and vegetation were collected, i.e. above-ground biomass trees and herbs, amount of tree litter, under-ground biomass of trees.
The rapid development of vegetation was occured in sites with spontaneous succession but slower formation of A horizont could lead to limitation of vegetation by lack of water especially in period with increased evapotranspiration. Selected trees from each sites were harvested and each biomass compartment was destructively analysed.
Total content of carbon (C), nitrogen (N) and phosphorus (P) was analysed in dried and mashed samples of biomass and soil. In result, total amount of biomass, C, N, P was higher on alder sites in compared to spontaneous succession sites.
Higher values of biomass, C and N of reclaimed sites were achieved through alder ability to fix atmospheric N2. Production of litter in succession sites was up to twice than alder sites.Litter from alder decomposed faster and released nutrients become available to plants.
Alder increase the availability of N and P in soils, C accumulation in plant biomass and sequestration of C into the soil. Alder reclamation due to its ability fix atmospheric N2 and high amount of N in litter leads to faster development of degraded soil in compare to succession.