Modelling the probability of microhabitat formation on trees using cross-sectional data

The rate of TreM formation per unit diameter growth was modelled as a function of tree diameter at breast height (DBH), and the model was calibrated considering cross-sectional observations TreMs on trees of different sizes. The model predicted realistic TreM formation rates at the tree and stand levels in forests dominated by Abies alba and Fagus sylvatica. This approach opens new perspectives to the analysis of forest biodiversity conservation strategies

Influence of spruce decline in stands of the Bialowieza National Park on natural oak regeneration

The study aimed at analyzing the oak population structure was performed on the 29−hectare plot representing stands dominated by spruce in the strict reserve of the Białowieża National Park. It revealed that oaks represent two distinct cohorts: the old, emerged in the late 1800s, and the new that is being established in the area subject to mass decline of spruce. We suggest that the first regeneration wave was the result of ceasing the frequent ground fire regime that prevented the regeneration of trees except for pine. The current wave has been prompted by a set of changes in the habitat quality, following the breakdown of dense spruce−dominated stands. These changes, such as access to sunlight, accelerated decomposition of spruce litter, local exposure of mineral soil, and protective structures of lying spruce logs, provide regeneration advantage to oak and other intolerant species

What is the use of studies carried out on the permanent plots in the Bialowieza National Park?

The purpose of the strictly protected area of the Białowieża National Park (BNP) established in early 1900s, was to protect a compact block of the Białowieża forest from any direct human influence and activity. Its founders considered it a “laboratory of nature.” In 1936, five rectangular plots with a total area of ca. 15.5 ha (ca. 0.3% of the BNP) were set up for regular monitoring of stand development with regards to the initial state and variability of soil conditions. During the first 76 years of the project, a steady increase in the proportion of hornbeam and lime tree at the expense of shade-intolerant species was observed. This trend has been interpreted by the researchers involved in the monitoring of the permanent BNP plots to constitute a biodiversity-threatening development caused by preservation efforts. Such an interpretation has been widely incorporated in the public debate by political authorities and the forestry sector. In this critical article I challenge the major arguments presented by the key expert in silviculture, prof. B. Brzeziecki. My criticism is directed at the methodological approach as well as at the data interpretation

Old trees and dead wood in forest ecosystems of Poland - assumptions, methodology and initial results of the project

Projekt Stare drzewa i martwe drewno w ekosystemach leśnych Polski jest inicjatywą mającą na celu uzupełnienie stanu wiedzy o zasobach biocenotycznie cennych drzew i martwego drewna w polskich lasach, stworzenie podstaw do opracowania uniwersalnego wskaźnika naturalności lasów oraz poszerzenia społecznej świadomości odnośnie potrzeby zachowania leśnej bioróżnorodności. Projekt jest w założeniu realizowany na 120 powierzchniach próbnych reprezentujących szeroko rozpowszechnione w Polsce i w Europie typy lasów. Na powierzchniach próbnych dokonywany jest ilościowy pomiar zasobności martwego drewna oraz jakościowa ocena zjawisk związanych z martwym drewnem i leśną bioróżnorodnością. Opracowany dla potrzeb projektu system kodowania umożliwia rejestrację szerokiego spektrum obserwacji różnego typu. W projekcie biorą udział wolontariusze – studenci nauk leśnych i biologicznych z Polski i Europy, wspierani przez koordynatora merytorycznego projektu. Dotychczasowe doświadczenia wykazały skuteczność stosowanej metody w ocenie stanu lasu, prowadzonej przez nie-specjalistów i mogą posłużyć za podstawy do systematycznych badań nad naturalnością stanu lasu.Project Old trees and dead wood in forest ecosystems of Poland is aimed at the assessment of biocenotically important trees and decaying wood resources in Polish forests, creating the basis for elaborating the indicator of forest naturalness and education in the subject of forest biodiversity and conservation. In course of the project 120 study plots will be established, representing forest types widely distributed in Poland and Europe. Quantity and quality of dead wood will be recorded, along with wide range of phenomena related to decaying wood, forest naturalness and habitat diversity. The project is based on the participation of volunteers – students of biology, forest and conservation sciences from Polish and foreign universities. Our volunteers are supported by scientific experts. Preliminary results evidenced usefulness of presented method in the estimation of forest conditions, conducted by non-specialists and therefore might be used as guidelines for regular forest monitoring