Tree-Ring Analysis Reveals Density-Dependent Vulnerability to Drought in Planted Mongolian Pines

Population density influences tree responses to environmental stresses, such as drought and high temperature. Prolonged drought negatively affects the health of Mongolian pines in forests planted by the Three-North Shelter Forest Program in North China. To understand the relationship between stand density and drought-induced forest decline, and to generate information regarding the development of future management strategies, we analyzed the vulnerability to drought of planted Mongolian pines at three stand densities. A tree-ring width index for trees from each density was established from tree-ring data covering the period 1988–2018 and was compared for differences in radial growth. Resistance (Rt), recovery (Rc), resilience (Rs), and relative resilience (RRs) in response to drought events were calculated from the smoothed basal area increment (BAI) curves. The high-density (HDT) group showed a consistently lower tree-ring width than the border trees (BT) and low-density (LDT) groups. The BAI curve of the HDT group started to decrease five years earlier than the LDT and BT groups. Pearson correlation analysis revealed that the radial growth of all of the groups was related to precipitation, relative humidity (RH), potential evapotranspiration (ET0), and standardized precipitation evapotranspiration index (SPEI) in the previous October and the most recent July, indicating that Mongolian pine trees of different densities had similar growth–climate relationships. Over the three decades, the trees experienced three severe drought events, each causing reduced tree-ring width and BAI. All of the groups showed similar Rc to each drought event, but the HDT group exhibited significantly lower Rt, Rs, and RRs than the BT group, suggesting that the HDT trees were more vulnerable to repeated drought stress. The RRs of the HDT group decreased progressively after each drought event and attained <0 after the third event. All of the groups showed similar trends regarding water consumption under varying weather conditions, but the HDT group showed significantly reduced whole-tree hydraulic capability compared with the other two groups. From these results, HDT trees exhibit ecophysiological memory effects from successive droughts, including sap flux dysfunction and higher competition index, which may prevent recovery of pre-drought growth rates. HDT trees may be at greater risk of mortality under future drought disturbance.

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Responses of radial growth, wood density and fiber traits to planting space in poplar plantations at a lowland site

Journal of Forestry Research ◽

10.1007/s11676-021-01382-0 ◽

2021 ◽

Author(s):

Yanhua Zhang ◽

Shengzuo Fang ◽

Ye Tian ◽

Linlin Wang ◽

Yi Lv

Keyword(s):

Tree Ring ◽

Radial Growth ◽

Pearson Correlation ◽

Wood Fiber ◽

Negative Relationship ◽

Basic Density ◽

Ring Width ◽

Tree Ring Width ◽

Wood Basic Density ◽

Fiber Traits

AbstractPoplar is raw material for various panel, paper and fiber products. The 12 sample trees of clone Nanlin-895 from four spacings were destructively harvested after thirteen growing seasons to assess the influence of spacing on radial growth and wood properties. Spacing significantly affected tree-ring width and wood basic density (p < 0.05) but not fiber traits. The highest diameter and wood basic density at breast height (1.3 m) was in 6 m × 6 m and 3 m × 8 m spacings, respectively. However, no significant differences in tree-ring width, wood basic density and fiber traits were observed among the four sampling directions in discs taken at 1.3 m for each spacing. Growth rings from the pith and tree heights had significant effects on wood basic density and fiber anatomical characteristics, highlighting obvious temporal-spatial variations. Pearson correlation analysis showed a significantly negative relationship of tree-ring width to wood basic density, fiber length and fiber width, but a significantly positive relationship to hemicellulose. There was no relationship with cellulose and lignin contents. Based on a comprehensive assessment by the TOPSIS method, the 6 m × 6 m spacing is recommended for producing wood fiber at similar sites in the future.

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Tree growth across the Nepal Himalaya during the last four centuries

Progress in Physical Geography Earth and Environment ◽

10.1177/0309133317714247 ◽

2017 ◽

Vol 41 (4) ◽

pp. 478-495 ◽

Cited By ~ 15

Author(s):

UK Thapa ◽

S St. George ◽

DK Kharal ◽

NP Gaire

Keyword(s):

Tree Ring ◽

Tree Growth ◽

Environmental Changes ◽

Ring Width ◽

High Elevation ◽

Forest Growth ◽

Tree Ring Width ◽

Early 19Th Century ◽

Tree Ring Data ◽

Instrumental Records

The climate of Nepal has changed rapidly over the recent decades, but most instrumental records of weather and hydrology only extend back to the 1980s. Tree rings can provide a longer perspective on recent environmental changes, and since the early 2000s, a new round of field initiatives by international researchers and Nepali scientists have more than doubled the size of the country’s tree-ring network. In this paper, we present a comprehensive analysis of the current tree-ring width network for Nepal, and use this network to estimate changes in forest growth nation-wide during the last four centuries. Ring-width chronologies in Nepal have been developed from 11 tree species, and half of the records span at least 290 years. The Nepal tree-ring width network provides a robust estimate of annual forest growth over roughly the last four centuries, but prior to this point, our mean ring-width composite fluctuates wildly due to low sample replication. Over the last four centuries, two major events are prominent in the all-Nepal composite: (i) a prolonged and widespread growth suppression during the early 1800s; and (ii) heightened growth during the most recent decade. The early 19th century decline in tree growth coincides with two major Indonesian eruptions, and suggests that short-term disturbances related to climate extremes can exert a lasting influence on the vigor of Nepal’s forests. Growth increases since AD 2000 are mainly apparent in high-elevation fir, which may be a consequence of the observed trend towards warmer temperatures, particularly during winter. This synthesis effort should be useful to establish baselines for tree-ring data in Nepal and provide a broader context to evaluate the sensitivity or behavior of this proxy in the central Himalayas.

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Forward modelling of tree-ring width and comparison with a global network of tree-ring chronologies

Climate of the Past ◽

10.5194/cp-10-437-2014 ◽

2014 ◽

Vol 10 (2) ◽

pp. 437-449 ◽

Cited By ~ 49

Author(s):

P. Breitenmoser ◽

S. Brönnimann ◽

D. Frank

Keyword(s):

Data Assimilation ◽

Tree Ring ◽

Ring Width ◽

Global Network ◽

Threshold Temperature ◽

Tree Ring Width ◽

Data Set ◽

Observation Operator ◽

Tree Ring Data ◽

Wide Range

Abstract. We investigate relationships between climate and tree-ring data on a global scale using the process-based Vaganov–Shashkin Lite (VSL) forward model of tree-ring width formation. The VSL model requires as inputs only latitude, monthly mean temperature, and monthly accumulated precipitation. Hence, this simple, process-based model enables ring-width simulation at any location where monthly climate records exist. In this study, we analyse the growth response of simulated tree rings to monthly climate conditions obtained from the CRU TS3.1 data set back to 1901. Our key aims are (a) to assess the VSL model performance by examining the relations between simulated and observed growth at 2287 globally distributed sites, (b) indentify optimal growth parameters found during the model calibration, and (c) to evaluate the potential of the VSL model as an observation operator for data-assimilation-based reconstructions of climate from tree-ring width. The assessment of the growth-onset threshold temperature of approximately 4–6 °C for most sites and species using a Bayesian estimation approach complements other studies on the lower temperature limits where plant growth may be sustained. Our results suggest that the VSL model skilfully simulates site level tree-ring series in response to climate forcing for a wide range of environmental conditions and species. Spatial aggregation of the tree-ring chronologies to reduce non-climatic noise at the site level yielded notable improvements in the coherence between modelled and actual growth. The resulting distinct and coherent patterns of significant relationships between the aggregated and simulated series further demonstrate the VSL model's ability to skilfully capture the climatic signal contained in tree-ring series. Finally, we propose that the VSL model can be used as an observation operator in data assimilation approaches to reconstruct past climate.

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Linkages between Climate, Radial Growth and Defoliation in Abies pinsapo Forests from Southern Spain

Forests ◽

10.3390/f11091002 ◽

2020 ◽

Vol 11 (9) ◽

pp. 1002

Author(s):

Rafael M. Navarro-Cerrillo ◽

Antonio Gazol ◽

Carlos Rodríguez-Vallejo ◽

Rubén D. Manzanedo ◽

Guillermo Palacios-Rodríguez ◽

...

Keyword(s):

Tree Ring ◽

Radial Growth ◽

Early Summer ◽

Southern Spain ◽

Tree Age ◽

Severe Drought ◽

Recent Climate ◽

Tree Ring Data ◽

Abies Pinsapo ◽

Old Trees

Systematic forest networks of health monitoring have been established to follow changes in tree vigor and mortality. These networks often lack long-term growth data, but they could be complemented with tree ring data, since both defoliation and radial growth are proxies of changes in tree vigor. For instance, a severe water shortage should reduce growth and increase tree defoliation in drought-prone areas. However, the effects of climatic stress and drought on growth and defoliation could also depend on tree age. To address these issues, we compared growth and defoliation data with recent climate variability and drought severity in Abies pinsapo old and young trees sampled in Southern Spain, where a systematic health network (Andalucía Permanent Plot Network) was established. Our aims were: (i) to assess the growth sensitivity of old and young A. pinsapo trees and (ii) to test if relative changes in radial growth were related with recent defoliation, for instance, after severe droughts. We also computed the resilience indices to quantify how old and young trees recovered growth after recent droughts. Wet-cool conditions during the prior autumn and the current early summer improved the growth of old trees, whereas late-spring wet conditions enhanced the growth of young trees. Old trees were more sensitive to wet and sunny conditions in the early summer than young trees. Old and young trees were more responsive to the Standardized Precipitation-Evapotranspiration Index drought index of June–July and July–August calculated at short (one–three months) and mid (three–six months) time scales, respectively. Old trees presented a higher resistance to a severe drought in 1995 than young trees. A positive association was found between stand defoliation and relative growth. Combining monitoring and tree ring networks is useful for the detection of early warning signals of dieback in similar drought-prone forests.

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Independent Aridity and Drought Pieces of Evidence Based on Meteorological Data and Tree Ring Data in Southeast Banat, Vojvodina, Serbia

Atmosphere ◽

10.3390/atmos10100586 ◽

2019 ◽

Vol 10 (10) ◽

pp. 586 ◽

Cited By ~ 1

Author(s):

Milivoj B. Gavrilov ◽

Wenling An ◽

Chenxi Xu ◽

Milica G. Radaković ◽

Qingzhen Hao ◽

...

Keyword(s):

Tree Ring ◽

Air Temperature ◽

Meteorological Data ◽

Ring Width ◽

Surface Air Temperature ◽

Aridity Index ◽

Precipitation Trend ◽

Positive Temperature ◽

Tree Ring Width ◽

Tree Ring Data

In this study, aridity data and tree ring data were collected in Northern Serbia, in Southeast (SE) Banat, a subregion within Vojvodina, and Vojvodina at large. They were each investigated independently. The De Martonne Aridity Index and the Forestry Aridity Index are derived from examining the relationship between precipitation and surface air temperature data sets sourced from seven meteorological stations in SE Banat, and from 10 meteorological stations located in Vojvodina as a whole. Vojvodina is a large territory and used as the control area, for the period 1949–2017. The Palmer Drought Severity Index was derived for the period 1927–2016, for both SE Banat and the totality of Vojvodina. The results of the Tree Ring Width Index were obtained from samples collected in or around the villages of Vlajkovac and Šušara, both located in SE Banat, for the period 1927–2017. These tree ring records were compared with three previous aridity and drought indices, and the meteorological data on the surface air temperature and the precipitation, with the objective being to evaluate the response of tree growth to climate dynamics in the SE Banat subregion. It was noted that the significant positive temperature trends recorded in both areas were too insufficient to trigger any trends in aridity or the Tree Ring Width Index, as neither displayed any change. Instead, it appears that these climatic parameters only changed in response to the precipitation trend, which remained unchanged during the investigated period, rather than in response to the temperature trend. It appears that the forest vegetation in the investigated areas was not affected significantly by climate change in response to the dominant temperature increase.

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Reconstruction of potential evapotranspiration over western Himalaya in India based on tree ring-width records

Quaternary International ◽

10.1016/j.quaint.2019.05.005 ◽

2020 ◽

Vol 547 ◽

pp. 145-151 ◽

Cited By ~ 1

Author(s):

Somaru Ram ◽

H.N. Singh ◽

Ramesh Kumar Yadav ◽

S.S. Nandargi ◽

Manoj K. Srivastava

Keyword(s):

Tree Ring ◽

Potential Evapotranspiration ◽

Ring Width ◽

Western Himalaya ◽

Tree Ring Width

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Tree-ring model interprets growth decline in natural stands of loblolly pine in the southeastern United States

Canadian Journal of Forest Research ◽

10.1139/x89-096 ◽

1989 ◽

Vol 19 (5) ◽

pp. 612-621 ◽

Cited By ~ 35

Author(s):

Robert Zahner ◽

Joseph R. Saucier ◽

Richard K. Myers

Keyword(s):

Tree Ring ◽

Loblolly Pine ◽

Radial Growth ◽

Ring Width ◽

Stand Density ◽

Climatic Conditions ◽

Radial Increment ◽

Aggregate Model ◽

Ring Model ◽

Pine Stands

Annual ring widths and ring areas from 131 even-aged, natural, well-stocked stands of loblolly pine (Pinustaeda L.) in the Piedmont region were analyzed to reveal possible causes of a previously reported decline in radial growth. A linear aggregate model was used to separate independent factors that are known to contribute to radial growth variation in this species. Stand, site, and climatic conditions were reconstructed for each stand for the 36-year period 1949–1984 from previous inventories and from weather records at appropriately located stations. Within each of six 5-year age-classes, the model identified declines in both ring width and ring area associated with stand density, climate changes, and the passage of time. Regional climate first ameliorated this decline as pine stands passed from droughty conditions early in the 36-year period to a favorable climate during the middle of the period, and the decline accelerated later with the return of dry conditions toward the end of the period. The tree-ring model simulates a decline in radial increment in trees in natural pine stands between the ages of 20 and 45 years in the Piedmont which has averaged 1% per year since 1950. Part of the downward trend was attributed to increased competition, part to regional drought, and a considerable part to unidentified factors, possibly regional atmospheric deposition.

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Radial growth of Scots pine and Norway spruce stands as an indicator of soil and environmental conditions

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/875/1/012074 ◽

2021 ◽

Vol 875 (1) ◽

pp. 012074

Author(s):

B Aparin ◽

B Babikov ◽

D Zolotukhin ◽

E Mingareeva

Keyword(s):

Norway Spruce ◽

Tree Ring ◽

Scots Pine ◽

Radial Growth ◽

Ring Width ◽

Tree Ring Width ◽

Average Growth ◽

Cyclical Pattern ◽

Spruce Stands ◽

Successive Change

Abstract The study presents an analysis of radial growth of Scots pine and Norway spruce trees growing on drained soils formed on varved clays at the sample sites of the Lisino Experimental Forestry (Lisino). Based on dendrochronological studies in Lisino, it has been found that the radial growth of Scots pine and Norway spruce is a sensitive indicator of changes in the soil water regime, climate, and phytocenotic relationships. On the basis of the character of tree-ring width growth, the growth charts allowed distinguishing zones with close to average growth values, as well as with increased and decreased values of radial growth. The cyclical pattern of tree ring width is well expressed in the successive change of zones. The availability of dendrochronological research materials with precise spatial and temporal reference makes it possible to organize monitoring of radial growth of trees as an indicator of changes in climate and habitat conditions.

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Responses of Larix principis-rupprechtii Radial Growth to Climatic Factors at Different Elevations on Guancen Mountain, North-Central China

Forests ◽

10.3390/f13010099 ◽

2022 ◽

Vol 13 (1) ◽

pp. 99

Author(s):

Jiachuan Wang ◽

Shuheng Li ◽

Yili Guo ◽

Qi Yang ◽

Rui Ren ◽

...

Keyword(s):

Tree Ring ◽

Radial Growth ◽

Climatic Factors ◽

Pearson Correlation ◽

Coniferous Forest ◽

Ring Width ◽

Central China ◽

Summer Drought ◽

Climate Trends

Larix principis-rupprechtii is an important afforestation tree species in the North China alpine coniferous forest belt. Studying the correlations and response relationships between Larix principis-rupprechtii radial growth and climatic factors at different elevations is helpful for understanding the growth trends of L. principis-rupprechtiind its long-term sensitivity and adaptability to climate change. Pearson correlation, redundancy (RDA), and sliding analysis were performed to study the correlations and dynamic relationships between radial growth and climatic factors. The main conclusions are as follows: (1) The three-elevation standard chronologies all exhibited high characteristic values, contained rich climate information and were suitable for tree-ring climatological analyses. (2) Both temperature and precipitation restricted low-elevation L. principis-rupprechtii radial growth, while monthly maximum temperatures mainly affected mid-high-elevation L. principis-rupprechtii radial growth. (3) Mid-elevation L. principis-rupprechtii radial growth responded to climate factors with a “lag effect” and was not restricted by spring and early summer drought. (4) Long-term sliding analysis showed that spring temperatures and winter precipitation were the main climatic factors restricting L. principis-rupprechtii growth under warming and drying climate trends at different elevations. The tree-ring width index and Palmer drought severity index (PDSI) were positively correlated, indicating that L. principis-rupprechtii growth is somewhat restricted by drought. These results provide a reference and guidance for L. principis-rupprechtii management and sustainable development in different regions under warming and drying background climate trends.

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Assessing the relation of tree ring width with climate variables in South Korea through multi-gridded dataset

10.5194/egusphere-egu21-3845 ◽

2021 ◽

Author(s):

Nasrin Salehnia ◽

Jinho Ahn

Keyword(s):

Tree Ring ◽

Potential Evapotranspiration ◽

Regression Line ◽

Ring Width ◽

Climatic Research Unit ◽

P Value ◽

Climate Variables ◽

Tree Ring Width ◽

Significance Level ◽

The Past

The Tree Ring Width (TRW) records are one of the main paleoclimate proxies that estimate the past climate variability. TRW measurements pave the way for scientists to produce sequences from various kinds of trees and reconstruct climate variables over the past years. Understanding the relation between TRW and climate variables in the past would help us analyze climate change events. This study has applied multi-gridded datasets to find the relations and model TRW data with different climate variables in South Korea's northeast. We utilized TRW data related to our case study that is available on the NOAA website; furthermore, we have checked three primary gauges, namely Agmerra (The Modern-Era Retrospective Analysis for Research and Applications), CRU TS4.03 (Climatic Research Unit Time-Series version 4.03), and APHRODITE's (Asian Precipitation-Highly-Resolved Observational Data Integration Towards Evaluation) for climate variables. In the first step, we have checked the relation between the gauges' precipitation data and observation TRW. According to the obtained efficiency criteria, CRU performed the best consequences. In the second step, we have tried to model observation TRW as a dependent variable and four climate variables of CRU (precipitation, minimum temperature, potential evapotranspiration, and diurnal temperature range) as independent ones over 1969-1998. We have created a linear regression model and determined the accurate coefficients for each climate variable. Besides, we have examined the observation TRW and modeled TRW data. The results showed that with R2 &#160;&#8776; 0.40 and a p-value of 0.0323, the regression line was linearly significant at the 95 percent significance level. It represents that our model is acceptable. We will extend our model with Artificial Intelligence methods and try to apply other TRW stations in the future step. In this way, we may produce highly accurate models and fill the gaps for future researches.

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