Hydrologic Effects Of Mountain Pine Beetle Infestation And Salvage Harvesting Operations

This project was developed to identify a set of risk indicators to predict the risk of summer-ground loss at the watershed level within the Vanderhoof Forest District (VFD) and others, subsequent to the mountain pine beetle (MPB) infestation of lodgepole pine stands. This report was done in relation to the VFD annual cut of stands, and the following difficultings that operators found in running their equipment in wet versus dry soils in harvest years. Risk indicators were selected from available GIS information, aerial photographs, and local knowledge. The most effective indicators for predicting the risk of wet-ground areas at the watershed level were found to be lodgepole pine content, understorey, drainage density, sensitive soils, and the topographic index, all of whose values are available from provincial databases. The work includes information on materials and methods, results and discussion, the authors' conclusions, as well as recommendations.--Includes text from document.

This paper presents the results of a project done to assess the potential for impacts and changes to the peak-flow regime throughout various sub-basins of the Fraser River Watershed. The vast size and the physical complexity of the Fraser River Basin make it extremely difficult to directly measure the hydrologic effects of beetle kill and salvage harvesting. As a result, a hydrology model has been used to assess the hydrologic consequences of the current outbreak. The project is part of a larger effort in quantifying the water resource impacts of the pine beetle and salvage harvesting across a range of watershed scales.--Includes text from document.

The current synthesis is a review of research examining the effects of large-scale mountain pine beetle (MPB)-related disturbance conducted predominantly over the past five years. The emphasis is on research that explicitly examines the impact of beetle kill (or biotic disturbance in general) and the cumulative effects of large scale salvage harvesting operations in response to beetle kill. In general, forest disturbance has been found to increase snow accumulation and melt, reduce interception loss and evaporation, and increase runoff and stream flow.--Document.

"This study examines the impact of mountain pine beetle infestation on forest canopy structure on the Nechako Plateau, and the resulting impacts on snow accumulation and ablation under varied climatic conditions. Stand-scale results were used to drive a physically-based, distributed hydrological model of the Van Tine Creek watershed and assess watershed-scale hydrologic response to four harvesting/infestation scenarios."--Document.

This document provides a synthesis of recently completed studies to assess the ecological consequences of forest management after attack by mountain pine beetle or other large-scale disturbances. Studies are assessed for their contributions to gaps in knowledge previously identified in the Mountain Pine Beetle Initiative Working Paper "Evaluating effects of large scale salvage logging for mountain pine beetle on terrestrial and aquatic vertebrates," which was published in 2004. This report focuses on studies developed through the federal Mountain Pine Beetle Initiative, the federal Mountain Pine Beetle Program, and the complementary BC Forest Science Program. Relevant information from other jurisdictions is sometimes included to augment those studies. Topics examined are: the impacts of beetle kill and salvage operations on habitat attributes; the impacts of beetle kill and salvage operations on attendant processes, such as snag fall rates, light interception, and snow accumulation; and the wildlife response to large-scale beetle outbreaks and management strategies. For each of these three topics, we provide a summary of: research to date; pertinent findings to date; and gaps in research.

This paper reports on the investigation of the influence of the mountain pine beetle infestation and salvage harvesting on small stream and riparian zone ecological function, shade, and temperature. Small streams (less than a 2 m bankfull width) were selected because they are the most prominent stream type within a watershed and they determine many ecological characteristics of larger downstream channels.--Document.

The mountain pine beetle (MPB) epidemic is creating disturbances with unprecedented values of equivalent cut area over larger watersheds. While the effect of these disturbances on the watershed hydrologic response could be significant, it cannot be inferred from the current literature. The present knowledge of hydrologic changes resulting from forest disturbances is based on experiments conducted either at the stand level or on small watersheds less than few square kilometres. The main objective of this study is to predict the magnitude of the impact of MPB infestations and treatments by salvage logging on the water yield and peak flow regimes and the subsequent implications on channel geomorphology at multiple scales.--Document.