Search results for "peat bog"

The Mathematical Modeling of Ca And Fe Distribution In Peat Layers

2015

Bogs have been formed by an accumulation of peat - a light brown-to-black organic material, built up from partial decomposition of mosses and other bryophytes, sedges, grasses, shrubs, or trees under waterlogged conditions. The total peatlands area in Latvia covers 698 918 ha or 10.7% of the entire territory. Knowledge’s of peat metals content are important for any kind of peat using. Experimental determination of metals in peat is very long and expensive work. Using experimental data mathematical model for calculation of concentrations of metals in different points for different layers can help to very easy and fast to find approximately concentration of metals or trace elements. The resul…

On Mathematical Modelling of Metals Distribution in Peat Layers

2014

In this paper we consider averaging and finite difference methods for solving the 3-D boundary-value problem in multilayered domain. We consider the metals Fe and Ca concentration in the layered peat blocks. Using experimental data the mathematical model for calculation of concentration of metals in different points in peat layers is developed. A specific feature of these problems is that it is necessary to solve the 3-D boundary-value problems for elliptic type partial differential equations (PDEs) of second order with piece-wise diffusion coefficients in the layered domain. We develop here a finite-difference method for solving of a problem of one, two and three peat blocks with periodica…

THE MATHEMATICAL MODELING OF METALS CONTENT IN PEAT

2015

Metals deposition in peat can aid to evaluate impact of atmospheric or wastewaters pollution and thus can be a good indicator of recent and historical changes in the pollution loading. For peat using in agriculture, industrial, heat production etc. knowledge of peat metals content is important. Experimental determination of metals in peat is very long and expensive work. Using experimental data the mathematical model for calculation of concentrations of metals in different points for different layers is developed. The values of the metals (Ca, Mg, Fe, Sr, Cu, Zn, Mn, Pb, Cr, Ni, Se, Co, Cd, V, Mo) concentrations in different layers in peat taken from Knavu peat bog from four sites are deter…

Vidzemes un Latgales purvu apskats

1943

Sārnates purvs un tā techniskās izmantošanas projekts

1942

Sedas purva pētīšanas dati un tehniskās izmantošanas projekts

1942

Parasitoids (Hymenoptera) of leaf-spinning moths (Lepidoptera) feeding on Vaccinium uliginosum L. along an ecological gradient in central European pe…

2011

Parasitoids of leaf-spinning Lepidoptera associated with two isolated central European peat bogs were investigated. Five families of parasitoid Hymenoptera (Braconidae, lchneumonidae, Eulophidae, Pteromalidae and Encyrtidae) were recorded. Three categories were recognised: (1) primary parasitoids, (2) facultative hyperparasitoids and (3) obligatory hyperparasitoids. Ten species of Braconidae, five species and seven marked morphospecies among lchneumonidae, and three species of Chalcidoidea were identified. Despite of some niche-specific (but less host-specific) parasitoids, all these hymenopterans are likely to be generalists and none of them were confirmed to be habitat and/or host special…

Effect of fertilization on growth of lingonberry (Vaccinium vitis-idaea L.)

2021

Received: January 29th, 2021 ; Accepted: April 10th, 2021 ; Published: April 20th, 2021 ; Correspondence: andis.karlsons@lu.lv Today, most of the global berry crop of Vaccinium vitis-idaea L. is obtained from wild berries. In recent years, however, their cultivation has become slightly more widespread, especially as demand has increased. As the commercial production of lingonberries is a completely new fruit-growing sector in Latvia, research on mineral nutrition, development of the crop production system and proper fertilizer management is critically important. The objective of this study was to elucidate the effect of different fertilizer rates on the nutrient status of lingonberry plant …