Leaf Water Potential in a Mixed Mediterranean Forest from Machine Learning and Unmanned Aerial Vehicle (UAV)-Based Hyperspectral Imaging DOI Creative Commons

Netanel Fishman,

Yehuda Yungstein,

Assaf Yaakobi

et al.

Remote Sensing, Journal Year: 2024, Volume and Issue: 17(1), P. 106 - 106

Published: Dec. 31, 2024

Leaf water potential (ψleaf) is a key indicator of plant status, but its measurement labor-intensive and limited in spatial coverage. While remote sensing has emerged as useful tool for estimating vegetation ψleaf remains unexplored, particularly mixed forests. Here, we use spectral indices derived from unmanned aerial vehicle-based hyperspectral imaging machine learning algorithms to assess mixed, multi-species Mediterranean forest comprised five woody species: Pinus halepensis, Quercus calliprinos, Cupressus sempervirens, Ceratonia siliqua, Pistacia lentiscus. Hyperspectral images (400–1000 nm) were acquired monthly over one year, concurrent with measurements each species. Twelve thousands normalized difference index (NDSI) combinations evaluated. Three algorithms—random (RF), extreme gradient boosting (XGBoost), support vector (SVM)—were used model ψleaf. We compared the results linear models based on NDSI. SVM, using species information feature, performed best relatively good assessment (R2 = 0.53; RMSE 0.67 MPa; rRMSE 28%), especially considering small seasonal variance (±σ 0.8 MPa). Predictions sempervirens 0.80) lentiscus 0.49), which had largest variances > 1 Aggregating data at plot scale ‘general’ markedly improved 0.79, 0.31 13%), providing promising monitoring The fact that non-species-specific, could predict implies such can also be coarser resolution satellite data. Our study demonstrates combining imagery non-invasive estimation forests while highlighting challenges capturing interspecies variability.

Language: Английский

Cones and consequences: the false dichotomy of conifers vs broad‐leaves has critical implications for research and modelling DOI
Kate M. Johnson, Matilda J. M. Brown, Katya I. Bandow

et al.

New Phytologist, Journal Year: 2025, Volume and Issue: unknown

Published: April 22, 2025

Summary In plant science research and modelling, particularly from the northern hemisphere, terms ‘needle‐leaved’ ‘conifer’ along with ‘broad‐leaved’ ‘angiosperm’ are often used synonymously, creating false dichotomy that conifers needle‐leaved angiosperms broad‐leaved. While these equivalences may be largely correct in temperate they do not hold true equatorial southern hemisphere forests. Confounding broad‐leaved present significant issues empirical modelling. Here, we highlight likely origins impacts of misusing conifer‐related terminology, misinterpretation ensues its implications. We identify issue a focus on Pinaceae coin term ‘Pinaceae panacea’ to describe this. provide recommendations for future research: standardising use definitions shifting away using as model group all conifers.

Language: Английский

Citations

0
The intricacies of vegetation responses to changing moisture conditions DOI Open Access
Julia K. Green

New Phytologist, Journal Year: 2024, Volume and Issue: 244(6), P. 2156 - 2162

Published: Oct. 6, 2024

A long-standing debate looks at whether air or soil dryness is more limiting to vegetation water use and productivity. The answer has large implications for future ecosystem functioning, as atmospheric predicted increase globally while changes in moisture are be far variable. Here, I review the complexities that contribute this debate, including strong coupling between dryness, widespread heterogeneity hydraulic traits, acclimations, adaptations stress. discuss solutions improve understanding modeling of sensitivity how different types observational data can used together gain insight into response stress across spatial temporal scales.

Language: Английский

Citations

3
Stand density and local climate drive allocation of GPP to aboveground woody biomass DOI Creative Commons
Steven A. Kannenberg, Flurin Babst, Mallory L. Barnes

et al.

New Phytologist, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 23, 2025

Summary The partitioning of photosynthate among various forest carbon pools is a key process regulating long‐term sequestration, with allocation to aboveground woody biomass (AGBC) in particular playing an outsized role the global cycle due its slow residence time. However, directly estimating fraction gross primary productivity (GPP) that goes AGBC has historically been difficult and time‐consuming, leaving us persistent uncertainties. We used extensive dataset tree‐ring chronologies co‐located at flux towers assess coupling between GPP, calculate fixed allocated AGBC, understand drivers variability this fraction. found annual GPP were rarely correlated, represented only small ( c . 9%) carbon. This varied considerably across sites was driven by differences stand density site climate. Annual suppressed 30% during drought remained below average for years afterward. These results imply assumptions relatively stationary other plant tissues could lead systematic biases modeled accumulation different thus

Language: Английский

Citations

0
Comparative Carbon Allocation and Soil Carbon Storage in Three Revegetated Shrublands in the Mu Us Desert DOI Open Access
Zongrui Lai, A. J. Jin, Wei Feng

et al.

Forests, Journal Year: 2025, Volume and Issue: 16(4), P. 586 - 586

Published: March 27, 2025

Revegetation in arid and semi-arid regions is a pivotal strategy for mitigating desertification controlling soil erosion by enhancing carbon storage woody biomass wind-induced erosion. Despite its recognized importance, critical gap remains understanding how distributed across different plant compartments (leaves, stems, litter, roots) this distribution influences dynamics. In study, we examined allocation between aboveground (shoot litterfall) belowground (coarse fine components, as well the composition vertical of three 20-year-old shrub plantations—Salix psammophila, Corethrodendron fruticosum, Artemisia desertorum—in northwest China. Total litter were highest S. psammophila plantation (3689.29 g m−2), followed C. fruticosum (1462.83 m−2) A. desertorum (761.61 m−2). contrast, at 1 m depth was greatest (12,831.18 (7349.24 (5375.80 Notably, also exhibited proportions stable organic (heavy-fraction) inorganic carbon, while had lowest. Across all plantations, light-fraction displayed distinct distributions, heavy-fraction did not show significant spatial patterns. A strong correlation found fractions microbial nitrogen, suggesting that communities key drivers stabilization turnover. These findings underscore importance composition, root traits, activity determining accumulation following revegetation. The study highlights need to investigate species-specific mechanisms, such rhizodeposition dynamics necromass stabilization, elucidate redistribution pathways ecosystems.

Language: Английский

Citations

0
Drought decreases carbon flux but not transport speed of newly fixed carbon from leaves to sinks in a giant bamboo forest DOI

Xiaogai Ge,

Yu Cong,

Yonghui Cao

et al.

Journal of Ecology, Journal Year: 2025, Volume and Issue: unknown

Published: May 5, 2025

Abstract Carbon (C) allocation among different plant tissues is crucial for maintaining C balance in forest ecosystems, especially under changing climate conditions. The partitioning of newly assimilated tissues, interconnected ramets and soil forests dominated by giant clonal plants, such as moso bamboo ( Phyllostachys edulis ), the influence drought on this remain poorly understood. In August 2019, we performed situ labelling entire crown R0 (ramets that emerged 2019) with 13 CO 2 plots subjected to a 5‐year or left untreated (ambient control) subtropical China. We then traced signatures leaves, twigs fine roots R0, R1 2018 are connected R0) R2 2017 R1), well organic (SOC) respiration over course 1‐year post‐labelling. Drought reduced leaf assimilation its sink but did not alter velocity transport from source compared controls. peak signal was observed day 15 SOC 5 respired both ambient control forests. Labelled detected 3 7 This study reveals new assimilates produced ‘younger’ preferentially retained within their own meet demands rather than being allocated neighbouring ramets. Synthesis . large bamboo, can may affect plant–soil systems. Our findings highlight complexity these suggest integration mitigate drought‐induced dieback older through resource sharing change.

Language: Английский

Citations

0
A decade of lost growth in old trees: aging shapes the impacts of drought and late frost events on European beech DOI Creative Commons
Álvaro Rubio‐Cuadrado, Isabel Dorado‐Liñán, Rosana López

et al.

Agricultural and Forest Meteorology, Journal Year: 2025, Volume and Issue: 370, P. 110601 - 110601

Published: May 7, 2025

Language: Английский

Citations

0
Context‐dependent effects of below‐ground carbon transfer: Limited benefits from sunlit pines to shaded oaks DOI Creative Commons
Stav Livne‐Luzon, Hagar Fox, Rotem Cahanovitc

et al.

Functional Ecology, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 2, 2024

Abstract Despite gaining significant attention in recent years, it remains unclear whether mycorrhizal fungi distribute meaningful amounts of resources among trees ways that increase the fitness receiving trees. To investigate this, we used pairs shaded and unshaded Pinus halepensis or Quercus calliprinos saplings, growing both inter‐ intra‐specific combinations outdoors forest soil. We examined combined effects indirect direct below‐ground connections on tree performance Non‐Structural Carbohydrate (NSC) pools. Although did not observe any growth benefits, recipient oaks exhibited higher levels root branch NSC compared to their control counterparts, which were connected below‐ground. This finding suggests a potential benefit establishing connections. However, no such benefits observed other pines oaks. monitored carbon (C) flow from 13 CO 2 ‐labelled donor pine oak demonstrated C transfer also identified main fungal symbionts interacting with Our findings indicate are context‐dependent, manifesting nuanced alterations plant readily apparent through conventional metrics. Read free Plain Language Summary for this article Journal blog.

Language: Английский

Citations

1
Effects of Mixing Hippophae rhamnoides and Pinus tabuliformis on Ecosystem Carbon, Nitrogen, and Phosphorus Sequestration and Storage Capacity in the Loess Hilly Region, China DOI Open Access
Wenwei Yu,

Rumeng Jiang,

Wei Xiao-lan

et al.

Forests, Journal Year: 2024, Volume and Issue: 15(8), P. 1382 - 1382

Published: Aug. 7, 2024

Mixed forests created by incorporating nitrogen-fixing tree species offer enhanced ecological advantages compared with consisting of only one type species. These benefits include habitat rehabilitation and the promotion biodiversity. Nevertheless, impact introducing on ecosystem carbon (C), nitrogen (N), phosphorus (P) sequestration storage capacity in Loess Plateau China remains inadequately explored. To examine changes C, N, P, mixed plantations P. tabulaeformis H. rhamnoides (HrPt) were selected as research object, pure (Hr) (Pt) control. The results indicated that comparison to forest, HrPt significantly increased C N stocks but decreased P stocks. In addition, soil layer accounted for more than 60% forest ecosystems vegetation layer. Moreover, improved rates relative rates. Furthermore, physicochemical properties can be inferred from redundancy analysis showing 66.79% 0.06% Hr, 44.84% Pt, well 44.28% 0.04% HrPt, respectively. conclusion, introduction N-fixing was conducive accumulation N. substantial significance scientific guidance restoration degraded landscapes stewardship Hilly Region, providing essential data nutrient ecosystems.

Language: Английский

Citations

0
14C-age of carbon used to grow fine roots reflects tree carbon status DOI Open Access
Boaz Hilman, Emily F. Solly, Frank Hagedorn

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 17, 2024

Summary “Bomb” 14 C ages in trees indicate the time elapsed between carbon fixation into nonstructural (NSC) and its use for metabolism growth. It remains unknown why newly grown aboveground tissues have a narrow range of young C-ages, while fine root can span decades. We measured two coniferous species along an alpine treeline ecotone used mixing model to estimate fraction NSC that is metabolically active. expected greater growth limitation higher would supply more freshly fixed respiration, active NSC, carbohydrates, roots, resulting younger C-ages grow tissues. Results confirmed increase fresh with elevation. Needle branch was supported by (< 2 yr) little elevation influence, older declined from 10 6 yr Massive allocation needles branches could explain their C-ages. Variable reflect tree status, when limits contribution new belowground, represent delivery roots.

Language: Английский

Citations

0
Drought induces opposite changes in organ carbon and soil organic carbon to increase resistance on moso bamboo DOI Creative Commons

Xiaogai Ge,

Yi-qing Mao,

Benzhi Zhou

et al.

Frontiers in Plant Science, Journal Year: 2024, Volume and Issue: 15

Published: Nov. 26, 2024

The variety of organs carbon concentration may be important for tree survival rate, drought resistance and subsequent recovery. However, it remains unclear how affect structural carbohydrate (SC) non-structural (NSC) export transport on clonal plant, which can correlated with sustain physiological metabolism group by resource sharing. To better understand the adaption ability clone plants to linkage organ soil organic (SOC) fractions, we assessed long-term affects its impact SOC fractions among moso bamboo (

Language: Английский

Citations

0