Incorporating stand parameters in nonlinear height-diameter mixed-effects model for uneven-aged Larix gmelinii forests

Frontiers in Forests and Global Change, Journal Year: 2025, Volume and Issue: 7

Published: Jan. 7, 2025

Tree attributes, such as height (H) and diameter at breast (D), are essential for predicting forest growth, evaluating stand characteristics developing yield models sustainable management. Measuring tree H is particularly challenging in uneven-aged forests compared to D. To overcome these difficulties, the development of updated reliable H-D crucial. This study aimed develop robust Larix gmelinii by incorporating variables. The dataset consisted 7,069 trees sampled from 96 plots Northeast China, encompassing a wide range densities, age classes, site conditions. Fifteen widely recognized nonlinear functions were assessed model relationship effectively. Model performance was using root mean square error (RMSE), absolute (MAE), coefficient determination (R 2 ). Results identified Ratkowsky (M8) best performer, achieving highest R (0.74), lowest RMSE (16.47%) MAE (12.50%), statistically significant regression coefficients (p < 0.05). Furthermore, M8 modified into 5 generalized (GMs) adding stand-variables (i.e., height, volume their combination), results indicate that GM2 0.82% 13.7%. We employed mixed-effects modeling approach with both fixed random effects account variations individual plot level, enhancing predictive accuracy. explained 71% variability trends residuals. calibrated response calibration method, through EBLUP theory. Our findings suggest stand-level variables representing plot-specific can further improve fit mixed- models. These advancements provide authorities enhanced tools supporting

Language: Английский

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The Effect of Balanced N, P and K Fertilization on Fine Root Traits and Soil Properties in Sapindus mukorossi

Forests, Journal Year: 2024, Volume and Issue: 15(1), P. 94 - 94

Published: Jan. 3, 2024

To uncover the relationship between fine root traits and soil properties of trees under different fertilization treatments is important for understanding nutrient acquisition strategies woody oilseed plants scientific management. An experiment randomized complete block design was conducted in a Sapindus mukoross plantation using combinations nitrogen (N), phosphorus (P) potassium (K) fertilizers at levels (Control: 0 kg·ha−2 N, P K; level 1: 300 250 P, 200 2: 600 500 400 3: 900 750 K). The response to application investigated by measuring indices. results showed that: (1) surface main location roots. In 0–20 cm layer, FRB, RLD, FSRL, RAD were significantly increased treatment compared with control. (2) SOC, TN, TP, TK, AP, AK AN soils higher than those control group treatments, except pH. (3) Correlation analysis that FRB RLD positively correlated while TP AP negatively FSRL RAD. RDA content factor which influenced mukoross. study revealed K fertilizers, provided theoretical support cultivation species, suggested rational management forests, species widely planted southern region China.

Language: Английский

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Unveiling the Influence of Climate and Technology on Forest Efficiency: Evidence from Chinese Provinces

Forests, Journal Year: 2024, Volume and Issue: 15(5), P. 742 - 742

Published: April 24, 2024

The objective of this study is to examine the impact climate and technology on forest efficiency (FE) in China’s provinces from 2002 2020. First, used SBM-data envelopment analysis (SBM-DEA) estimate Chinese provinces’ FE using multidimensional inputs outputs. influence assessed temperature, precipitation, sunlight hours, carbon dioxide levels second phase. A index was created principal component (PCA) for a complete estimation. In addition prior research, we analyze through two technological indicators: (i) research development, (ii) investment forests. Furthermore, explore non-linear economic development both quality. regression by CupFM CupBC found that temperature precipitation increase FE, whereas hours emissions decrease it. positive association observed between Climate Index1, negative relationship noted Index2, suggests forests positively conditions, signifying an improvement leads Technology boosts productivity climatic environmental Kuznets curve shows inverted U-shape FE. Similarly, have U-shaped EKC relationship. Urbanization reduces due human growth activity. Our findings are important management, change, sustainable policymakers scholars.

Language: Английский

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Spatiotemporal Dynamics of Fine Root Biomass in Chinese Fir (Cunninghamia lanceolata) Stumps and Their Impacts on Soil Chemical Properties

Forests, Journal Year: 2025, Volume and Issue: 16(2), P. 203 - 203

Published: Jan. 22, 2025

Stumps are residuals from artificial forest harvesting, persist in ecosystems, and have garnered attention for their ecological roles soil water conservation, carbon sequestration, regeneration. However, the spatiotemporal dynamics of stump fine root biomass impact on nutrient cycling remain unclear. This study focuses roots Chinese Fir (Cunninghamia lanceolata) stumps generated during construction national reserve forests at Xishan State Forest Farm, Linwu County, Hunan Province, 2014 to 2022. Employing a space-for-time substitution approach, we investigated (FRB) its effects chemical properties. The results indicated that FRB significantly differed with increasing residual time across various layers distances, an average annual loss rate 8.40%–9.96%. living (LFRB) was predominantly concentrated 0–20 cm layer decreased depth. Initially, LFRB closer stumps; however, this proximity effect diminished over time. There were no significant differences coefficients between layers, within vertical profile 95% span 15.1–15.9 years. there horizontal differences, 13.7–17.0 changes organic matter (SOM) total nitrogen (STN) content period exhibited trade-off relationship LFRB, SOM STN peaking 1 year after peak dead (DFRB), suggesting combined exudates decomposition enhancement. trend generally inverse soil’s phosphorus (STP) content, which gradually increased extended retention, indicating provide long-term source soil. also revealed can soils relatively long positively affect nutrients storage. These findings theoretical support management suggest retaining post-harvest maintain fertility functions.

Language: Английский

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Variation Patterns of Fine Root Biomass, Production, and Turnover Rates in Four Subtropical Forests of China

Forests, Journal Year: 2025, Volume and Issue: 16(2), P. 220 - 220

Published: Jan. 24, 2025

Fine roots (diameter ≤ 2 mm) play a critical role in regulating soil organic carbon storage and nutrient cycling forest ecosystems. However, the variability fine root biomass, production, turnover rates across different types remains poorly understood. This study investigates dynamics, including distribution, turnover, four major monoculture plantation forests subtropical China: Chinese fir (Cunninghamia lanceolata (Lamb.) Hook), Masson pine (Pinus massoniana Lamb.), sweet gum (Liquidambar formosana Hance), camphor tree (Cinnamomum camphora (L.) J. Presl). Using sequential coring method, samples were collected monthly to monitor live dead biomass depths (0–15 cm, 15–30 30–45 45–60 cm). production estimated using three methods: Max–Min, Integral Decision Matrix. The results showed that was highest (1.96 t ha−1), followed by (1.12 (0.89 (0.83 ha−1). Approximately 90% of total composed all types, highlighting their significant uptake. Both predominantly concentrated upper 0–30 cm layer, with notable decline deeper layers. (2.66–2.90 ha−1 a−1), (1.16–1.83 (0.87–0.97 (0.87–0.93 a−1). Turnover (1.25–1.36 (0.96–1.51 both (0.94–1.05 a−1 0.97–1.04 a−1, respectively). identifies differences dynamics among providing baseline data for optimizing management, particularly urban peri-urban areas. These insights can enhance reforestation efforts, ecosystem resilience, sustainable productivity.

Language: Английский

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Dynamics of fine-root decomposition and its response to site nutrient regimes in boreal drained-peatland and mineral-soil forests

Forest Ecology and Management, Journal Year: 2025, Volume and Issue: 582, P. 122564 - 122564

Published: March 1, 2025

Language: Английский

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Nitrogen-fixing tree species enhance the positive effects of tree species richness on soil organic carbon sequestration by increasing fine root phosphorus loss

CATENA, Journal Year: 2025, Volume and Issue: 254, P. 108927 - 108927

Published: March 12, 2025

Language: Английский

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Spatiotemporal evolution of vegetation phenology and its response to environmental factors in the upper and middle reaches of the Yellow River Basin

Journal of Environmental Management, Journal Year: 2025, Volume and Issue: 380, P. 124970 - 124970

Published: March 15, 2025

Language: Английский

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Forest Structure, Diversity, and Regeneration in a Community‐Managed Forest of Nepal: A Model for Carbon Sequestration and Sustainable Management

Plant-Environment Interactions, Journal Year: 2025, Volume and Issue: 6(2)

Published: March 16, 2025

ABSTRACT Community forestry, a participatory forest management system, encourages conservation, enhances carbon sequestration, and advances the Sustainable Development Goals (SDGs) by increasing community ownership of resource management. in terms policies practices, directly supports SDG‐1, SDG‐13, SDG‐15 promoting empowerment as well ecosystem health. It provides immediate benefits to local livelihoods enhancing access services such fuelwood, fodder, non‐timber products. Here, we assess regeneration conservation value Nepal recording seedlings, saplings, mature trees randomly sampled plots. The plots were structurally complex with rich tree diversity; most showed high diameter at breast height (DBH) differentiation diversity. Most species followed an abundance distribution seedlings > saplings adults, suggesting “good” regeneration. Tree stock was 137.6 tons per hectare positively associated density diversity negatively altitude. An increase one standard deviation index ~0.39 11.7% higher hectare. Plot‐level related lower heights. Overall, forestry successfully transformed degraded into quality within two decades, outperforming regional average Thus, forests can act effective model for sustainable are essential tools policymakers promote regeneration, structural diversity, storage, growth, utilization.

Language: Английский

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Associations between stand spatial structures and carbon sequestration on natural Larix gmelinii forests in Northeast China

Trees Forests and People, Journal Year: 2025, Volume and Issue: unknown, P. 100837 - 100837

Published: March 1, 2025

Language: Английский

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