Estimation of fuel loads and carbon stocks of forest floor in endemic Dalmatian black pine forests

Abstract Background National and international institutions periodically demand information on forest indicators that are used for global reporting. Among other aspects, the carbon accumulated in the biomass of forest species must be reported. For this purpose, one of the main sources of data is the National Forest Inventory (NFI), which together with statistical empirical approaches and updating procedures can even allow annual estimates of the requested indicators. Methods Stand level biomass models, relating the dry weight of the biomass with the stand volume were developed for the five main pine species in the Iberian Peninsula (Pinus sylvestris, Pinus pinea, Pinus halepensis, Pinus nigra and Pinus pinaster). The dependence of the model on aridity and/or mean tree size was explored, as well as the importance of including the stand form factor to correct model bias. Furthermore, the capability of the models to estimate forest carbon stocks, updated for a given year, was also analysed. Results The strong relationship between stand dry weight biomass and stand volume was modulated by the mean tree size, although the effect varied among the five pine species. Site humidity, measured using the Martonne aridity index, increased the biomass for a given volume in the cases of Pinus sylvestris, Pinus halepensis and Pinus nigra. Models that consider both mean tree size and stand form factor were more accurate and less biased than those that do not. The models developed allow carbon stocks in the main Iberian Peninsula pine forests to be estimated at stand level with biases of less than 0.2 Mg∙ha− 1. Conclusions The results of this study reveal the importance of considering variables related with environmental conditions and stand structure when developing stand dry weight biomass models. The described methodology together with the models developed provide a precise tool that can be used for quantifying biomass and carbon stored in the Spanish pine forests in specific years when no field data are available.

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A climate response function explaining most of the variation of the forest floor needle mass and the needle decomposition in pine forests across Europe

Plant and Soil ◽

10.1007/s11104-006-0061-9 ◽

2006 ◽

Vol 285 (1-2) ◽

pp. 97-114 ◽

Cited By ~ 17

Author(s):

C. Kurz-Besson ◽

M. M. Coûteaux ◽

B. Berg ◽

J. Remacle ◽

C. Ribeiro ◽

...

Keyword(s):

Response Function ◽

Forest Floor ◽

Pine Forests ◽

Climate Response ◽

Needle Decomposition ◽

Needle Mass

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Effects of forest roads on Ips sexdentatus infestation in black pine forest

Turkish Journal of Agriculture - Food Science and Technology ◽

10.24925/turjaf.v6i7.828-833.1690 ◽

2018 ◽

Vol 6 (7) ◽

pp. 828

Author(s):

Gonca Ece Özcan ◽

Korhan Enez ◽

Burak Arıcak

Keyword(s):

Bark Beetle ◽

Bark Beetles ◽

Forest Ecosystems ◽

Significant Risk ◽

Pine Forests ◽

Slope Aspect ◽

Black Pine ◽

Forest Roads ◽

Forest Road ◽

Ips Sexdentatus

Forest roads are important transportation equipment through forested areas in the rugged, mountainous terrain of northern Turkey. Forest roads harm forest ecosystems due to both the manner in which they are established and how they are used afterwards. Damage to trees that occur during road construction through forests stresses trees, which facilitates outbreaks of bark beetle populations. Bark beetles are significant risk to the health and productivity of Turkish pine forests and to pine forests worldwide. In particular, Ips sexdentatus (Boerner) (Coleoptera, Curculionidae, Scolytinae) is a particularly destructive species of bark beetle in Turkish forests. Their damage to coniferous trees threatens the sustainability of the forest ecosystems. This study primarily aims to assess the intensity of damage that I. sexdentatus inflicts on Pinus nigra J.F.Arnold stands relative to several parameters: the distance to the nearest forest road, aspect (shady - sunny), slope (0–15% or >15%), and other stand characteristics. In this study, we show how damage by an I. sexdentatus infestation in pure black pine stands varies with distance to forest roads and in situ edaphic factors. We sampled 45 plots (400 m2 each), slope, aspect and distances to the nearest forest road was determined using ArcGIS software and the region’s road network overlays. Results showed that trees located within 100 m from the nearest forest road were the most severely damaged ones. The intensity of I. sexdentatus damage was about 16% in a hectare. Trees that were in 16–20 cm diameter class were damaged more often. I. sexdentatus damage did not show any significant correlation with the slope, aspect or degree of canopy closure.

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Thinning and Burning Effects on Long-Term Litter Accumulation and Function in Young Ponderosa Pine Forests

Forest Science ◽

10.1093/forsci/fxaa018 ◽

2020 ◽

Vol 66 (6) ◽

pp. 761-769

Author(s):

Matt Busse ◽

Ross Gerrard

Keyword(s):

Ponderosa Pine ◽

Forest Floor ◽

Prescribed Burning ◽

Mineral Soil ◽

Pine Forests ◽

Organic Layer ◽

Litter Accumulation ◽

Ponderosa Pine Forests ◽

Essential Components

Abstract We measured forest-floor accumulation in ponderosa pine forests of central Oregon and asked whether selected ecological functions of the organic layer were altered by thinning and repeated burning. Experimental treatments included three thinning methods applied in 1989 (stem only, whole tree, no thin—control) in factorial combination with prescribed burning (spring 1991 and repeated in 2002; no burn—control). Forest-floor depth and mass were measured every 4–6 years from 1991 to 2015. Without fire, there was little temporal change in depth or mass for thinned (270 trees ha−1) and control (560–615 trees ha−1) treatments, indicating balanced litterfall and decay rates across these stand densities. Each burn consumed 50–70 percent of the forest floor, yet unlike thinning, postfire accumulation rates were fairly rapid, with forest-floor depth matching preburn levels within 15–20 years. Few differences in forest-floor function (litter decay, carbon storage, physical barrier restricting plant emergence, erosion protection) resulted from thinning or burning after 25 years. An exception was the loss of approximately 300 kg N ha−1 because of repeated burning, or approximately 13 percent of the total site N. This study documents long-term forest-floor development and suggests that common silvicultural practices pose few risks to organic layer functions in these forests. Study Implications: Mechanical thinning and prescribed fire are among the most widespread management practices used to restore forests in the western US to healthy, firewise conditions. We evaluated their effects on the long-term development of litter and duff layers, which serve dual roles as essential components of soil health and as fuel for potential wildfire. Our study showed that thinning and burning provided effective fuel reduction and resulted in no adverse effects to soil quality in dry ponderosa pine forests of central Oregon. Repeated burning reduced the site carbon and nitrogen pools approximately 9–13 percent, which is small compared to C located in tree biomass and N in mineral soil. Litter accumulation after burning was rapid, and we recommend burning on at least a 15–20-year cycle to limit its build-up.

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