We consider a two-echelon timber supply chain in which the first echelon consists of several stands to be harvested and the second echelon consists of mills to be procured with logs of different length. This problem aims at minimizing harvesting and transportation costs for one production period, while satisfying demand expressed as mix of volumes of specific log types. Harvesting cost, which i...

Climate change is expected to cause an increased frequency of extreme events such as heavy floods and major storms. Such stochastic events have an immediate impact on surface water quality, but the long-term effects are largely unknown. In this study, we assess long-term monitoring data from two Swedish headwater catchments affected by extreme weather events. At one site, where nitrogen effects...

The problems of the environmental management in river basins are treated as periphery problems. Though, these areas are often included in great reserves of natural resources of the nation, their contribution to the main land is quite often in terms of forest, water, wildlife, tourism and leisure industries. Forest and forest eco-systems of north-east India in general and Manipur in particular, ...

We measured nitrogen transformations and loss following forest clearing in a relatively fertile tropical forest site. Nitrogen mineralization, nitrification, and amounts of ammonium and nitrate increased substantially in surface soils during the 6 mo following burning, then returned to background levels. The nitrogen content of microbial biomass declined to half its original value 6 mo after cl...

BACKGROUND The high spatio-temporal variability of aboveground biomass (AGB) in tropical forests is a large source of uncertainty in forest carbon stock estimation. Due to their spatial distribution and sampling intensity, pre-felling inventories are a potential source of ground level data that could help reduce this uncertainty at larger spatial scales. Further, exploring the factors known to ...

Afforestation is a significant cause of global peatland degradation. In some regions, afforested bogs are now undergoing clear-felling and restoration, often known as forest-to-bog restoration. We studied differences in water-table depth (WTD) porewater chemistry between intact, afforested, restored at raised bog blanket location. Solute concentrations principal component analysis suggested tha...

This article documents master logboat-builder Alalae Mohamed’s construction of a ngalawa fishing vessel in Bagamoyo, Tanzania. The is an extended logboat with double outrigger and lateen sail used by low-income, artisanal fishers. It the most common marine type East African coast. follows process from Alalae’s selection felling tree(s) to launching vessel. outlines tools materials used, details...

error is an inevitable part of life and cannot be completely eliminated, but it can be minimized. a root cause analysis is a technique for understanding the systematic error causes that is involved beyond a person or people to implement an errors and including field and environmental causes of errors when occur in this situation too. an important factor of an error occurrence is a root cause (c...

Abstract Key message We studied size distributions of decay-affected Norway spruce trees using cut-to-length harvester data. The data comprised tree-level decay and severity recordings from 101 final felling stands, which enabled to analyze relationships between all trees. Distribution matching technique was used transfer the distribution into diameter at breast height (DBH) Context Stem ( Pice...