Effects of Forest Structure On Dendroctonus Valens Damage Under Natural and Human Disturbances

Abstract Background In recent years, the red turpentine beetle (Dendroctonus valens, RTB), an invasive pest species has spread northward along the distribution of pine forests, forming a potential threat to healthy pine forests in North China. Previous studies have shown that natural (e.g., fire) and human (e.g., felling) disturbances can significantly promote bark beetle damage. However, few studies have considered the effect of forest landscape structure on bark beetle damage under disturbance conditions. Here we used generalized linear models and generalized linear mixed models to explore the effects of multi-scale factors on RTB damage under different disturbance conditions (presence or absence) in 109 forest stands in the Heilihe National Nature Reserve, Inner Mongolia. Result Disturbance (i.e., fire and stolen felling) could significantly promote the occurrence of RTB. In the absence of disturbance, small-scale stand factors (i.e., aspect and canopy density) played important roles in the prediction of RTB damage. In the presence of disturbance, forest landscape structure (i.e., forest isolation) was the main factor affecting RTB invasion. Conclusion In the presence of disturbance, the forest structure played an important role in the process of the diffusion of RTB from the surrounding habitat to the disturbance. This study, which emphasizes the potential importance of forest landscape structure on RTB spread, not only provides new insights into understanding the roles of large-scale factors but also assists in the implementation of pest management programs.

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The Effects of Landscape Structure and Stand-Scale Factors on Dendroctonus Valens Damage Under Disturbance Conditions in North China

10.21203/rs.3.rs-769961/v1 ◽

2021 ◽

Author(s):

Zhongyi Zhan ◽

Lixia Wang ◽

Linfeng Yu ◽

Lili Ren ◽

Yizhou Liu ◽

...

Keyword(s):

Bark Beetle ◽

Landscape Structure ◽

North China ◽

Pine Forests ◽

Invasive Pest ◽

Pest Species ◽

Multi Scale ◽

Dendroctonus Valens ◽

Scale Factors ◽

Beetle Damage

Abstract Background In recent years, the red turpentine beetle (Dendroctonus valens, RTB), an invasive pest species has spread northward along the distribution of pine forests, forming a potential threat to healthy pine forests in North China. Previous studies have shown that natural (e.g., fire) and human (e.g., felling) disturbances can significantly promote bark beetle damage. However, few studies have considered the effect of multi-scale factors on bark beetle damage under disturbance conditions. Here, we investigated RTB damage (entrance holes) in 98 forest stands with and without disturbance (fire or stolen felling) in the Heilihe National Nature Reserve, Inner Mongolia, which is considered to be in the early stage of RTB outbreak. We assessed the effects of forest landscape structure (forest proportion and host connectivity) and stand-scale characteristics on RTB damage under different disturbance conditions (presence or absence). In addition, we also explored the effects of fire and stolen felling disturbance on RTB damage and the significant differences between them. Result Disturbance (i.e., fire and stolen felling) could significantly promote the occurrence of RTB and there was no significant difference between the two types of disturbance. In the absence of disturbance, small stand-scale factors (i.e., aspect and canopy cover) played important roles in the prediction of RTB damage. In the presence of disturbance, forest proportion within a radius of 250 m was the main factor affecting RTB invasion. Higher forest coverage could reduce the migration of RTB from the surrounding environment to the disturbance area, thus reducing RTB damage. In addition, we observed a positive relationship between elevation and RTB invasion. Conclusion Landscape structure and stand-scale factors had different effects on RTB invasion under different disturbance conditions. This study not only provides new insights into understanding the roles played by multi-scale factors in RTB damage but also assists in the implementation of pest management programs.

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Forest-landscape structure mediates effects of a spruce bark beetle (Dendroctonus rufipennis) outbreak on subsequent likelihood of burning in Alaskan boreal forest

Forest Ecology and Management ◽

10.1016/j.foreco.2016.03.036 ◽

2016 ◽

Vol 369 ◽

pp. 38-46 ◽

Cited By ~ 12

Author(s):

Winslow D. Hansen ◽

F. Stuart Chapin ◽

Helen T. Naughton ◽

T. Scott Rupp ◽

David Verbyla

Keyword(s):

Boreal Forest ◽

Bark Beetle ◽

Landscape Structure ◽

Forest Landscape ◽

Dendroctonus Rufipennis ◽

Spruce Bark Beetle ◽

Spruce Bark

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Decomposition and stabilization of organic matter in an old-growth tropical riparian forest: effects of soil properties and vegetation structure

10.21203/rs.3.rs-61797/v3 ◽

2020 ◽

Author(s):

Pedro Fernandes ◽

Andrea Teixeira Souza ◽

Marcel Tanaka ◽

Renata Sebastiani

Keyword(s):

Soil Properties ◽

Forest Structure ◽

Riparian Forest ◽

Chemical Properties ◽

Clay Content ◽

Small Scale ◽

Decomposition Rates ◽

Old Growth ◽

Scale Factors ◽

Stabilization Factor

Abstract Background: Nutrient cycling in tropical forests has a large importance for primary productivity, and decomposition of litterfall is a major process influencing nutrient balance in forest soils. Although large-scale factors strongly influence decomposition patterns, small-scale factors can have major influences, especially in old-growth forests that have high structural complexity and strong plant-soil correlations. Here we evaluated the effects of forest structure and soil properties on decomposition rates and stabilization of soil organic matter using the Tea Bag Index in an old-growth riparian forest in southeastern Brazil. These data sets were described separately using Principal Components Analysis (PCA). The main axes for each analysis, together with soil physical properties (clay content and soil moisture), were used to construct structural equations models that evaluated the different parameters of the TBI, decomposition rates and stabilization factor. The best model was selected using Akaike’s criterion.Results: Forest structure and soil physical and chemical properties presented large variation among plots within the studied forest. Clay content was strongly correlated with soil moisture and the first PCA axis of soil chemical properties, and model selection indicated that clay content was a better predictor than this axis. Decomposition rates presented a large variation among tea bags (0.009 and 0.098 g g-1 day-1) and were positively related with forest structure, as characterized by higher basal area, tree density and larger trees. The stabilization factor varied between 0.211 – 0.426 and was related to forest stratification and soil clay content.Conclusions: The old-growth forest studied presented high heterogeneity in both forest structure and soil properties at small spatial scales, that influenced decomposition processes and probably contributed to small-scale variation in nutrient cycling. Decomposition rates were only influenced by forest structure, whereas the stabilization factor was influenced by both forest structure and soil properties. Heterogeneity in ecological processes can contribute to the resilience of old-growth forests, highlighting the importance of restoration strategies that consider the spatial variation of ecosystem processes.

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DISTRIBUTION OF THE SMALL SPRUCE BARK BEETLE IPS AMITINUS (EICHHOFF, 1872) IN WESTERN SIBERIA

Russian Journal of Biological Invasions ◽

10.35885/1996-1499-2021-14-4-77-84 ◽

2021 ◽

Vol 14 (4) ◽

pp. 77-84

Author(s):

I. A. Kerchev ◽

S. A. Krivets ◽

E. M. Bisirova ◽

N. A. Smirnov

Keyword(s):

Bark Beetle ◽

Western Siberia ◽

Pine Forests ◽

Invasive Pest ◽

Pinus Sibirica ◽

Spruce Bark Beetle ◽

Pine Nut ◽

Spruce Bark ◽

Pinus Sibirica Du Tour ◽

Siberian Pine

The data on distribution of small spruce bark beetle Ips amitinus (Eichh.) (Coleoptera: Curculionidae: Scolytinae), a new invasive pest of European origin on the territory of Western Siberia are presented. Alien bark beetle species was recorded in the Siberian pine forests of the Tomsk, Kemerovo and Novosibirsk regions. According to the modern data the total invasion range is more than 30 thousand km² with a tendency to further expansion. The number outbreaks of I. amitinus in Siberian pine forests near settlements, in nature preservations and plantations of Pinus sibirica Du Tour cause significant harm to pine-nut harvesting and selective breeding.

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Decomposition and stabilization of organic matter in an old-growth tropical riparian forest: effects of soil properties and vegetation structure

Forest Ecosystems ◽

10.1186/s40663-021-00293-0 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Pedro Henrique de Godoy Fernandes ◽

Andréa Lúcia Teixeira de Souza ◽

Marcel Okamoto Tanaka ◽

Renata Sebastiani

Keyword(s):

Soil Properties ◽

Forest Structure ◽

Riparian Forest ◽

Chemical Properties ◽

Clay Content ◽

Small Scale ◽

Decomposition Rates ◽

Old Growth ◽

Scale Factors ◽

Stabilization Factor

Abstract Background Nutrient cycling in tropical forests has a large importance for primary productivity, and decomposition of litterfall is a major process influencing nutrient balance in forest soils. Although large-scale factors strongly influence decomposition patterns, small-scale factors can have major influences, especially in old-growth forests that have high structural complexity and strong plant-soil correlations. Here we evaluated the effects of forest structure and soil properties on decomposition rates and stabilization of soil organic matter using the Tea Bag Index (TBI) in an old-growth riparian forest in southeastern Brazil. These data sets were described separately using Principal Components Analysis (PCA). The main axes for each analysis, together with soil physical properties (clay content and soil moisture), were used to construct structural equations models that evaluated the different parameters of the TBI, decomposition rates and stabilization factor. The best model was selected using Akaike’s criterion. Results Forest structure and soil physical and chemical properties presented large variation among plots within the studied forest. Clay content was strongly correlated with soil moisture and the first PCA axis of soil chemical properties, and model selection indicated that clay content was a better predictor than this axis. Decomposition rates presented a large variation among tea bags (0.009 and 0.098 g·g− 1·d− 1) and were positively related with forest structure, as characterized by higher basal area, tree density and larger trees. The stabilization factor varied between 0.211–0.426 and was related to forest stratification and soil clay content. Conclusions The old-growth forest studied presented high heterogeneity in both forest structure and soil properties at small spatial scales, that influenced decomposition processes and probably contributed to small-scale variation in nutrient cycling. Decomposition rates were only influenced by forest structure, whereas the stabilization factor was influenced by both forest structure and soil properties. Heterogeneity in ecological processes can contribute to the resilience of old-growth forests, highlighting the importance of restoration strategies that consider the spatial variation of ecosystem processes.

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Monitoring Bark Beetle Forest Damage in Central Europe. A Remote Sensing Approach Validated with Field Data

Remote Sensing ◽

10.3390/rs12213634 ◽

2020 ◽

Vol 12 (21) ◽

pp. 3634 ◽

Cited By ~ 1

Author(s):

Angel Fernandez-Carrillo ◽

Zdeněk Patočka ◽

Lumír Dobrovolný ◽

Antonio Franco-Nieto ◽

Beatriz Revilla-Romero

Keyword(s):

Remote Sensing ◽

Central Europe ◽

Bark Beetle ◽

Forest Damage ◽

Economic Losses ◽

In Situ Data ◽

Damage Mapping ◽

Beetle Damage ◽

Forest Vitality ◽

Sentinel 2

Over the last decades, climate change has triggered an increase in the frequency of spruce bark beetle (Ips typographus L.) in Central Europe. More than 50% of forests in the Czech Republic are seriously threatened by this pest, leading to high ecological and economic losses. The exponential increase of bark beetle infestation hinders the implementation of costly field campaigns to prevent and mitigate its effects. Remote sensing may help to overcome such limitations as it provides frequent and spatially continuous data on vegetation condition. Using Sentinel-2 images as main input, two models have been developed to test the ability of this data source to map bark beetle damage and severity. All models were based on a change detection approach, and required the generation of previous forest mask and dominant species maps. The first damage mapping model was developed for 2019 and 2020, and it was based on bi-temporal regressions in spruce areas to estimate forest vitality and bark beetle damage. A second model was developed for 2020 considering all forest area, but excluding clear-cuts and completely dead areas, in order to map only changes in stands dominated by alive trees. The three products were validated with in situ data. All the maps showed high accuracies (acc > 0.80). Accuracy was higher than 0.95 and F1-score was higher than 0.88 for areas with high severity, with omission errors under 0.09 in all cases. This confirmed the ability of all the models to detect bark beetle attack at the last phases. Areas with no damage or low severity showed more complex results. The no damage category yielded greater commission errors and relative bias (CEs = 0.30–0.42, relB = 0.42–0.51). The similar results obtained for 2020 leaving out clear-cuts and dead trees proved that the proposed methods could be used to help forest managers fight bark beetle pests. These biotic damage products based on Sentinel-2 can be set up for any location to derive regular forest vitality maps and inform of early damage.

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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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Rocky pine forests in the High Coast Region in Sweden: structure, dynamics and history

Nature Conservation ◽

10.3897/natureconservation.38.34870 ◽

2020 ◽

Vol 38 ◽

pp. 101-130

Author(s):

Jennie Sandström ◽

Mattias Edman ◽

Bengt Gunnar Jonsson

Keyword(s):

Human Impact ◽

Fire History ◽

Dead Wood ◽

Forest Type ◽

Basal Area ◽

Pine Forests ◽

Small Scale ◽

Natural Dynamics ◽

Almost All ◽

High Degree

Almost all forests in Sweden are managed and only a small fraction are considered natural. One exception is low productive forests where, due to their limited economical value, natural dynamics still dominate. One example is the Scots pine (Pinus sylvestris L.) forests occurring on rocky and nutrient-poor hilltops. Although these forests represent a regionally common forest type with a high degree of naturalness, their dynamics, structure and history are poorly known. We investigated the structure, human impact and fire history in eight rocky pine forests in the High Coast Area in eastern Sweden, initially identified as good representatives of this forest type. This was done by sampling and measuring tree sizes, -ages, fire-scarred trees, as well as dead wood volumes and quality along three transects at each site. The structure was diverse with a sparse layer of trees (basal area 9 m2 and 640 trees larger than 10 cm ha-1) in various sizes and ages; 13 trees ha-1 were more than 300 years old. Dead wood (DW), snags and logs in all stages of decay, was present and although the actual DW (pine) volume (4.4 m3 ha-1) and number of units (53 ha-1) was low, the DW share of total wood volume was 18% on average. Dead wood can be present for several centuries after death; we found examples of both snags and logs that had been dead more than 300 years. Frequent fires have occurred, with an average cycle of 40 years between fires. Most fires occurred between 1500-1900 and many of them (13) during the 1600s. However, fires were probably small since most fire years were only represented at one site and often only in one or a few samples. The rocky pine forests in the High Coast Area are representative of undisturbed forests with low human impact, exhibiting old-growth characteristics and are valuable habitats for organisms connected to sun-exposed DW. Management of protected rocky pine forests may well include small-scale restoration fires and the limited DW volumes should be protected.

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