Lowering Stand Density Enhances Resiliency of Ponderosa Pine Forests to Disturbances and Climate Change

AbstractStand density affects not only structure and growth, but also the health of forests and, subsequently, the functions of forest ecosystems. Here, we integrated dendrochronology and repeated inventories for ponderosa pine research plots to determine whether long-term growth and mortality responded to climate trends and how varying stand density influenced the responses. The plots were established prior to 1975 on existing stands throughout northern California. Although annual temperature increased consistently for the last 65 years, ring-width indices produced by eliminating age and thinning effects failed to detect radial trend regardless of site quality. However, interannual variation for the indices was substantial, reflecting a strong influence of climate on tree growth. Plot-level basal area increments were significantly affected by tree mortality. Stand density index explained most variation of mortality. Lowering stand density enhanced remaining tree growth, reduced mortality, and increased stand resiliency to disturbances and climate change. Besides higher climate moisture indices or lower vapor pressure deficits, any treatments that improve tree vigor and reduce stress will have a similar effect to reducing stand density. Although neither biotic disturbances nor abiotic conditions can be controlled, forest managers can manage stand density appropriately to enhance resilience to climate change and disturbances.

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Site factors and stand conditions associated with Persian oak decline in Zagros mountain forests

Forest Systems ◽

10.5424/fs/2017263-11298 ◽

2018 ◽

Vol 26 (3) ◽

pp. e014 ◽

Cited By ~ 2

Author(s):

Ahmad Hosseini ◽

Seyed M. Hosseini ◽

Juan C. Linares

Keyword(s):

Climate Change ◽

Tree Mortality ◽

Stand Structure ◽

Basal Area ◽

Stand Density ◽

Change Scenario ◽

Climate Trends ◽

Site Factors ◽

Main Hypothesis ◽

Shallow Soils

Aim of study: Drought and stand structure are major and interconnected drivers of forest dynamics. Water shortage and tree-to-tree competition may interact under the current climate change scenario, increasing tree mortality. In this study, we aimed to investigate climate trends, site and stand structure effects on tree mortality, with the main hypothesis that drought-induced mortality is higher as competition increases.Area of study: Persian oak forests from Zagros Range, western Iran.Material and Methods: We split the study area into 20 topographical units (TUs), based on aspect, slope and elevation. In each TU, three 0.1 ha plots were established to quantify site and stand characteristics, namely the diameter of all trees and shrubs, stand density and basal area, canopy dieback and mortality. In addition, soil profiles were analyzed to obtain physical and chemical soil properties. Six transects 100 m length were established per TU to measure tree-to-tree competition for alive and dead trees.Main Results: The highest mortality rates and crown dieback were found at higher elevations and southern and western aspects. Our findings confirm increasing rates of tree mortality in stands with higher tree density and shallow soils. As regard links between climate change and forest decline, our results suggest that changing forest structure may have a significant impact on dust emission.Research highlights: Despite severe dry years occurred recently the study area, they are not significantly different than those recorded in the past. Stand structure appears as a modulating factor of climate change effects, linked to competition-related tree vulnerability to drought.

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Double Sampling Increases the Efficiency of Forest Floor Inventories for Arizona Ponderosa Pine Forests

International Journal of Wildland Fire ◽

10.1071/wf9940003 ◽

1994 ◽

Vol 4 (1) ◽

pp. 3 ◽

Cited By ~ 6

Author(s):

PZ Fule ◽

WW Covington

Keyword(s):

Ponderosa Pine ◽

Basal Area ◽

Stand Density ◽

Cost Effective ◽

Pine Forests ◽

Double Sampling ◽

Fuel Loading ◽

Size Classes ◽

Ponderosa Pine Forests ◽

Stand Density Index

Stand and natural fuel conditions were sampled in ponderosa pine forests in northern and central Arizona to develop predictive fuel depth and loading equations. Litter and duff depths can be estimated from measurements of stand density (basal area, stand density index). Although woody fuel loading did not correlate well with stand variables, correlations were found among loadings of different woody fuel size classes, so that results from a planar intersect tally of certain single woody fuel size classes may be used to predict the loadings in certain other size classes. The relatively low precision of estimates from these predictive equations can be substantially increased by applying them in a double sampling scheme. Making use of these predictive relationships, managers can devise simple, rapid, arid cost-effective fuel inventories that focus on the fuel category of interest. Fuel loads can be estimated at a desired precision with reduced investment of time and funds compared to a more comprehensive direct fuel inventory.

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Managing burned landscapes: evaluating future management strategies for resilient forests under a warming climate

International Journal of Wildland Fire ◽

10.1071/wf13184 ◽

2014 ◽

Vol 23 (7) ◽

pp. 915 ◽

Cited By ~ 14

Author(s):

K. L. Shive ◽

P. Z. Fulé ◽

C. H. Sieg ◽

B. A. Strom ◽

M. E. Hunter

Keyword(s):

Climate Change ◽

Ponderosa Pine ◽

Prescribed Burning ◽

Fire Severity ◽

Management Strategies ◽

Basal Area ◽

Forest Growth ◽

Climate Change Effects ◽

Ponderosa Pine Forests ◽

And Shifts

Climate change effects on forested ecosystems worldwide include increases in drought-related mortality, changes to disturbance regimes and shifts in species distributions. Such climate-induced changes will alter the outcomes of current management strategies, complicating the selection of appropriate strategies to promote forest resilience. We modelled forest growth in ponderosa pine forests that burned in Arizona’s 2002 Rodeo–Chediski Fire using the Forest Vegetation Simulator Climate Extension, where initial stand structures were defined by pre-fire treatment and fire severity. Under extreme climate change, existing forests persisted for several decades, but shifted towards pinyon–juniper woodlands by 2104. Under milder scenarios, pine persisted with reduced growth. Prescribed burning at 10- and 20-year intervals resulted in basal areas within the historical range of variability (HRV) in low-severity sites that were initially dominated by smaller diameter trees; but in sites initially dominated by larger trees, the range was consistently exceeded. For high-severity sites, prescribed fire was too frequent to reach the HRV’s minimum basal area. Alternatively, for all stands under milder scenarios, uneven-aged management resulted in basal areas within the HRV because of its inherent flexibility to manipulate forest structures. These results emphasise the importance of flexible approaches to management in a changing climate.

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Precommercial Thinning in a Ponderosa Pine Stand Affected by Armillaria Root Disease in Central Oregon: 30 Years of Growth and Mortality

Western Journal of Applied Forestry ◽

10.1093/wjaf/14.3.144 ◽

1999 ◽

Vol 14 (3) ◽

pp. 144-148 ◽

Cited By ~ 4

Author(s):

Gregory M. Filip ◽

Stephen A. Fitzgerald ◽

Lisa M. Ganio

Keyword(s):

Ponderosa Pine ◽

Tree Mortality ◽

Basal Area ◽

Stand Density ◽

Root Disease ◽

Diameter Growth ◽

Individual Tree ◽

Precommercial Thinning ◽

Tree Diameter ◽

Armillaria Root Disease

Abstract A 30-yr-old stand of ponderosa pine was precommercially thinned in 1966 to determine the effects of thinning on tree growth and mortality caused by Armillaria root disease in central Oregon. After 30 yr, crop tree mortality was significantly (P = 0.02) less in thinned plots than in unthinned plots. Tree diameter growth was not significantly (P = 0.17) increased by thinning. Crop-tree basal area/ac growth was significantly (P = 0.03) greater in thinned plots. Apparently, from a root disease perspective, precommercial thinning of pure ponderosa stands significantly decreases the incidence of crop-tree mortality after 30 yr and significantly increases basal area/ac growth but not individual tree diameter growth. Recommendations for thinning based on stand density index (SDI) are given. West. J. Appl. For. 14(3):144-148.

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The role of stand density on growth efficiency, leaf area index, and resin flow in southwestern ponderosa pine forests

Canadian Journal of Forest Research ◽

10.1139/x06-233 ◽

2007 ◽

Vol 37 (2) ◽

pp. 343-355 ◽

Cited By ~ 63

Author(s):

Nate G. McDowell ◽

Henry D. Adams ◽

John D. Bailey ◽

Thomas E. Kolb

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Ponderosa Pine ◽

Basal Area ◽

Stand Density ◽

Growth Efficiency ◽

Resin Flow ◽

Area Index ◽

Sapwood Area ◽

Ponderosa Pine Forests

We examined the response of growth efficiency (GE), leaf area index (LAI), and resin flow (RF) to stand density manipulations in ponderosa pine ( Pinus ponderosa Dougl. ex Laws.) forests of northern Arizona, USA. The study used a 40 year stand density experiment including seven replicated basal area (BA) treatments ranging from 7 to 45 m2·ha–1. Results were extended to the larger region using published and unpublished datasets on ponderosa pine RF. GE was quantified using basal area increment (BAI), stemwood production (NPPs), or volume increment (VI) per leaf area (Al) or sapwood area (As). GE per Al was positively correlated with BA, regardless of numerator (BAI/Al, NPPs/Al, and VI/Al; r2 = 0.84, 0.95, and 0.96, respectively). GE per As exhibited variable responses to BA. Understory LAI increased with decreasing BA; however, total (understory plus overstory) LAI was not correlated with BA, GE, or RF. Opposite of the original research on this subject, resin flow was negatively related to GE per Al because Al/As ratios decline with increasing BA. BAI, and to a lesser degree BA, predicted RF better than growth efficiency, suggesting that the simplest measurement with the fewest assumptions (BAI) is also the best approach for predicting RF.

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Thinning Ponderosa Pine Affected by Armillaria Root Disease: 40 Years of Growth and Mortality on an Infected Site in Central Oregon

Western Journal of Applied Forestry ◽

10.1093/wjaf/24.2.88 ◽

2009 ◽

Vol 24 (2) ◽

pp. 88-94 ◽

Cited By ~ 5

Author(s):

Gregory M. Filip ◽

Stephen A. Fitzgerald ◽

Kristen L. Chadwick ◽

Timothy A. Max

Keyword(s):

Ponderosa Pine ◽

Tree Mortality ◽

Basal Area ◽

Stand Density ◽

Root Disease ◽

Precommercial Thinning ◽

Fungal Host ◽

Commercial Thinning ◽

Armillaria Root Disease ◽

Stand Density Index

Abstract Portions of a 30-year-old stand of ponderosa pine were precommercially thinned in 1966 and commercially thinned in 2000 at age 64 years to determine the effects of thinning from below on tree growth and mortality caused by Armillaria root disease in central Oregon. Thirty years after precommercial thinning, leave-tree mortality was significantly less in thinned plots than in unthinned plots, but leave-treeߝdiameter growth was not significantly increased by thinning. Leave-tree basal area (BA) per acre growth, however, was significantly greater in thinned plots.In 2007 at age 71 years, 7 years after commercial thinning of the same plots that were precommercially thinned in 1966, leave-tree mortality was less in thinned plots than in unthinned plots, but more time probably is necessary to adequately assess Armillaria-caused mortality after commercial thinning. Both tree diameter and BA growth were significantly increased by commercial thinning. Hypotheses on fungal-host dynamics are discussed, and recommendations for multiple thinning based on stand density index are given.

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Fire-induced erosion and millennial-scale climate change in northern ponderosa pine forests

Nature ◽

10.1038/nature03058 ◽

2004 ◽

Vol 432 (7013) ◽

pp. 87-90 ◽

Cited By ~ 191

Author(s):

Jennifer L. Pierce ◽

Grant A. Meyer ◽

A. J. Timothy Jull

Keyword(s):

Climate Change ◽

Ponderosa Pine ◽

Pine Forests ◽

Ponderosa Pine Forests ◽

Millennial Scale

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Assessment of Biomass and Carbon Stock of planted teak forest in Terai region of Kumaun Himalaya, India

Indian Journal of Forestry ◽

10.54207/bsmps1000-2018-n97155 ◽

2018 ◽

Vol 41 (4) ◽

pp. 397-402

Author(s):

Tanuja Gahlot ◽

◽

Prachi Joshi ◽

Y.S. Rawat ◽

◽

...

Keyword(s):

Climate Change ◽

Carbon Sequestration ◽

Human Disturbance ◽

Carbon Stock ◽

Large Scale ◽

Basal Area ◽

Stand Density ◽

Positive Contribution ◽

Teak Plantation ◽

Forest Division

The ability of forests in atmospheric carbon sequestration is increasingly gaining attention. Present study deals with the estimation of biomass and carbon stock of the teak plantation in the terai central forest division in Kumaun, Uttarakhand State of India. Very few scientific studies were done regarding the teak plantation and the estimation of its biomass in Kumaun. Therefore this study was carried out in this region to assess the role played by teak plantation in climate change. The information regarding the changes in pattern of carbon storage is vital and important because it can be used by government and policymakers to predict the deposit pattern for changing climate. Three sites i.e., Kamola block (Site I), Kamola beat (Site II) and East Gadappu beat (Site III) were selected for the study. Large scale variations in biomass and carbon stock were noted among all three sites. Site III (East Gadappu) showed the maximum biomass and carbon stock (297.03 tha-1 and 143.18 tha-1) followed by site I (Kamola block) (241.9 tha -1and 117.27 t ha-1) and site II ( Kamola beat ) (175.76 t ha-1and 85.79 t ha-1). Although stand density and total basal area of the forest showed almost similar value on all three sites, still the differences in biomass and carbon stock at all sites indicated the positive contribution of biodiversity as shown in the results and negative implications of human disturbance to the forest.

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Zuwachs und Klimasensitivität von Baumarten im Ökogramm der kollinen und submontanen Stufe

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2015.0380 ◽

2015 ◽

Vol 166 (6) ◽

pp. 380-388 ◽

Cited By ~ 1

Author(s):

Pascale Weber ◽

Caroline Heiri ◽

Mathieu Lévesque ◽

Tanja Sanders ◽

Volodymyr Trotsiuk ◽

...

Keyword(s):

Climate Change ◽

Soil Properties ◽

Climate Sensitivity ◽

Tree Species ◽

Ring Width ◽

Basal Area ◽

Growth Potential ◽

Basal Area Increment ◽

Tree Ring Data ◽

Mean Sensitivity

Growth potential and climate sensitivity of tree species in the ecogram for the colline and submontane zone In forestry practice a large amount of empirical knowledge exists about the productivity of individual tree species in relation to site properties. However, so far, only few scientific studies have investigated the influence of soil properties on the growth potential of various tree species along gradients of soil water as well as nutrient availability. Thus, there is a research gap to estimate the productivity and climate sensitivity of tree species under climate change, especially regarding productive sites and forest ad-mixtures in the lower elevations. Using what we call a «growth ecogram», we demonstrate species- and site-specific patterns of mean annual basal area increment and mean sensitivity of ring width (strength of year-to-year variation) for Fagus sylvatica, Quercus spp., Fraxinus excelsior, Picea abies, Abies alba and Pinus sylvestris, based on tree-ring data from 508 (co-)dominant trees on 27 locations. For beech, annual basal area increment ( average 1957–2006) was significantly correlated with tree height of the dominant sampling trees and proved itself as a possible alternative for assessing site quality. The fact that dominant trees of the different tree species showed partly similar growth potential within the same ecotype indicates comparable growth limitation by site conditions. Mean sensitivity of ring width – a measure of climate sensitivity – had decreased for oak and ash, while it had increased in pine. Beech showed diverging reactions with increasing sensitivity at productive sites (as measured by the C:N ratio of the topsoil), suggesting an increasing limitation by climate at these sites. Hence, we derive an important role of soil properties in the response of forests to climate change at lower elevations, which should be taken into account when estimating future forest productivity.

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The impact of drought on tree growth in Mediterranean sites

10.5194/egusphere-egu21-8635 ◽

2021 ◽

Author(s):

Giovanna Battipaglia ◽

Francesco Niccoli ◽

Arturo Pacheco-Solana

Keyword(s):

Climate Change ◽

Tree Growth ◽

Sustainable Forest Management ◽

Climatic Factors ◽

Management Strategies ◽

Ring Width ◽

Limiting Factor ◽

Individual Tree ◽

Annual Growth Rings ◽

The Impact

Climate-induced forest mortality is a critical issue in the Mediterranean basin, with major consequences for the functioning of these key ecosystems. Indeed, in Mediterranean ecosystems, where water stress is already the most limiting factor for tree performance, climatic changes are expected to entail an increase in water deficit. In this context, annual growth rings can provide short- (e.g., years) and long-term (e.g., decades) information on how trees respond to drought events. With climate change, Pinus pinaster and Pinus pinea L. are expected to reduce their distribution range in the region, being displaced at low altitudes by more drought tolerant taxa such as sub Mediterranean Quercus spp.This study aims was to assess the physiological response of Pinus and Quercus species growing in the Vesuvio National park, located in Southern Italy and where an increase of temperature and drought events has been recorded in the recent years. Our preliminary results underlined the importance of temperature on the tree ring width of all the analyses species. The high temperatures can cause a change in the constant kinetics of the RuBisCo, leading to a consequent decrease in carboxylation rate and thus to a reduction in tree growth. On the other hand, also precipitation seemed to affect the growth of the sampled trees: indeed, in all the chronologies a reduction in growth was found after particular dry years: for example, the low rainfall in 1999 (455 mm/year) determined a drastic decline in growth in 2000 in all the species. In addition to the climatic factors, competition can also play an important role in the growth rate: dendrochronological analyzes have highlighted how stand specific properties (i.e. density, structure and composition) can influence individual tree responses to drought events. The knowledge of those researches should be integrated into sustainable forest management strategies to minimize the potential impacts of climate change on forest ecosystems.

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