Fertilization Effects on Fine Root Biomass, Production, and Turnover Rate in a Pinus rigida Plantation

Abstract Background: Fine roots make critical contributions to carbon stocks and terrestrial productivity, and multidiameter-class fine roots exhibit functional heterogeneity. However, the dynamic characteristics of multidiameter-class fine roots at different soil depths following thinning disturbances are poorly understood. We investigated the biomass, production, mortality and turnover rate of < 0.5 mm, 0.5–1 mm and 1–2 mm fine roots at 0-20 cm, 20-40 cm and 40-60 cm soil depths under five thinning intensities (0%, 15%, 30%, 45%, and 60%) in a secondary forest in the Qinling Mountains. Results: The biomass, production and turnover rate of < 0.5 mm fine roots fluctuated with increasing thinning intensity, while 0.5-1 mm and 1-2 mm fine root biomass significantly decreased. Thinning measures had no effects on fine root necromass (except for T4) or mortality. The fine root dynamic characteristics in deeper soils were more sensitive to thinning measures. Principal component analysis results show that increased < 0.5 mm fine root biomass and production resulted from increased shrub and herb diversity and biomass and decreased soil nutrient availability, stand volume and litter biomass, whereas 0.5-1 mm and 1-2 mm fine root biomass showed the opposite trends and change mechanisms. Conclusions: Our results provide evidence of the positive effect of thinning on very fine root (< 0.5 mm) biomass and production and the negative effect on thicker fine roots (0.5-1, 1-2 mm) or all fine root (< 2 mm) biomass. From the perspective of fine root biomass and productivity, T2 (30%) is recommended for use in secondary forests of the Qinling Mountains. Moreover, our results suggest that thinning practices have varied effects on the dynamic characteristics of multidiameter-class fine roots.

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Fine root biomass, production and turnover rates in plantations versus natural forests: effects of stand characteristics and soil properties

Plant and Soil ◽

10.1007/s11104-019-03948-8 ◽

2019 ◽

Vol 436 (1-2) ◽

pp. 463-474 ◽

Cited By ~ 5

Author(s):

Huiying Cai ◽

Fengri Li ◽

Guangze Jin

Keyword(s):

Soil Properties ◽

Biomass Production ◽

Root Biomass ◽

Fine Root ◽

Fine Root Biomass ◽

Natural Forests ◽

Turnover Rates ◽

Stand Characteristics

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An improved method for quantifying total fine root decomposition in plantation forests combining measurements of soil coring and minirhizotrons with a mass balance model

Tree Physiology ◽

10.1093/treephys/tpaa074 ◽

2020 ◽

Vol 40 (10) ◽

pp. 1466-1473

Author(s):

Xuefeng Li ◽

Kevan J Minick ◽

Tonghua Li ◽

James C Williamson ◽

Michael Gavazzi ◽

...

Keyword(s):

Fine Roots ◽

Root Biomass ◽

Turnover Rate ◽

Fine Root ◽

Fine Root Biomass ◽

Balance Model ◽

Root Decomposition ◽

Mass Balance Model ◽

Monthly Total ◽

Fine Root Decomposition

Abstract Accurate measurement of total fine root decomposition (the amount of dead fine roots decomposed per unit soil volume) is essential for constructing a soil carbon budget. However, the ingrowth/soil core-based models are dependent on the assumptions that fine roots in litterbags/intact cores have the same relative decomposition rate as those in intact soils and that fine root growth and death rates remain constant over time, while minirhizotrons cannot quantify the total fine root decomposition. To improve the accuracy of estimates for total fine root decomposition, we propose a new method (balanced hybrid) with two models that integrate measurements of soil coring and minirhizotrons into a mass balance model. Model input parameters were fine root biomass, necromass and turnover rate for Model 1, and fine root biomass, necromass and death rate for Model 2. We tested the balanced hybrid method in a loblolly pine plantation forest in coastal North Carolina, USA. The total decomposition rate of absorptive fine roots (ARs) (a combination of first- and second-order fine roots) using Models 1 and 2 was 107 ± 13 g m−2 year−1 and 129 ± 12 g m−2 year−1, respectively. Monthly total AR decomposition was highest from August to November, which corresponded with the highest monthly total ARs mortality. The ARs imaged by minirhizotrons well represent those growing in intact soils, evident by a significant and positive relationship between the standing biomass and the standing length. The total decomposition estimate in both models was sensitive to changes in fine root biomass, turnover rate and death rate but not to change in necromass. Compared with Model 2, Model 1 can avoid the technical difficulty of deciding dead time of individual fine roots but requires greater time and effort to accurately measure fine root biomass dynamics. The balanced hybrid method is an improved technique for measuring total fine root decomposition in plantation forests in which the estimates are based on empirical data from soil coring and minirhizotrons, moving beyond assumptions of traditional approaches.

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Temporal variation in fine-root biomass, production and mortality in a cool temperate forest covered with dense understory vegetation in northern Japan

Forest Ecology and Management ◽

10.1016/j.foreco.2013.09.015 ◽

2013 ◽

Vol 310 ◽

pp. 700-710 ◽

Cited By ~ 25

Author(s):

Karibu Fukuzawa ◽

Hideaki Shibata ◽

Kentaro Takagi ◽

Fuyuki Satoh ◽

Takayoshi Koike ◽

...

Keyword(s):

Temporal Variation ◽

Biomass Production ◽

Root Biomass ◽

Temperate Forest ◽

Fine Root ◽

Fine Root Biomass ◽

Understory Vegetation ◽

Cool Temperate ◽

Cool Temperate Forest ◽

Northern Japan

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Spatial and Seasonal Pattern of Fine Root Biomass and Turnover Rate in Different Land Use Systems in Central Himalaya, India

Russian Journal of Ecology ◽

10.1134/s1067413621010070 ◽

2021 ◽

Vol 52 (1) ◽

pp. 36-48

Author(s):

H. Karki ◽

K. Bargali ◽

S. S. Bargali

Keyword(s):

Land Use ◽

Root Biomass ◽

Turnover Rate ◽

Fine Root ◽

Seasonal Pattern ◽

Fine Root Biomass ◽

Central Himalaya ◽

Land Use Systems

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Fine root biomass, production and turnover in a fertilized Larix leptolepis plantation in central Korea

Ecological Research ◽

10.1046/j.1440-1703.2003.00559.x ◽

2003 ◽

Vol 18 (3) ◽

pp. 339-346 ◽

Cited By ~ 34

Author(s):

Yowhan Son ◽

Jae Hong Hwang

Keyword(s):

Biomass Production ◽

Root Biomass ◽

Fine Root ◽

Fine Root Biomass ◽

Larix Leptolepis

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Response of density-related fine root production to soil and leaf traits in coniferous and broad-leaved plantations in the semiarid loess hilly region of China

Journal of Forestry Research ◽

10.1007/s11676-021-01358-0 ◽

2021 ◽

Author(s):

Meimei Sun ◽

Bo-Chao Zhai ◽

Qiu-Wen Chen ◽

Guoqing Li ◽

Sheng Du

Keyword(s):

Root Biomass ◽

Turnover Rate ◽

Fine Root ◽

Black Locust ◽

Leaf Traits ◽

Fine Root Biomass ◽

Pine Plantations ◽

Root Production ◽

Fine Root Production ◽

Chinese Pine

AbstractFine roots are the most active and functional component of root systems and play a significant role in the acquisition of soil resources. Density is an important structural factor in forest plantations but information on changes in fine roots along a density gradient is limited. In this study, plantations of black locust (Robinia pseudoacacia L.) and Chinese pine (Pinus tabuliformis Carr.) with four density classes were analyzed for the influence of soil and leaf traits on fine root growth. Fine root biomass increased with stand density. High fine root biomass was achieved through increases in the fine root production and turnover rate in the high-density black locust plantations and through an increase in fine root production in the pine plantations. In the high-density Chinese pine stand, there was a high fine root turnover which, coupled with high fine root production, contributed to a high fine root biomass. Overall, fine root production and turnover rate were closely related to soil volumetric water content in both kinds of plantations, while fine root biomass, especially the component of necromass, was related to soil nutrient status, which refers to phosphorous content in black locust plantations and nitrogen content in Chinese pine plantations. There was a close linkage between leaf area index and fine root dynamics in the black locust plantations but not in the pine plantations.

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The dynamics of fine root length, biomass, and nitrogen content in two northern hardwood ecosystems

Canadian Journal of Forest Research ◽

10.1139/x93-312 ◽

1993 ◽

Vol 23 (12) ◽

pp. 2507-2520 ◽

Cited By ~ 241

Author(s):

Ronald L. Hendrick ◽

Kurt S. Pregitzer

Keyword(s):

Biomass Production ◽

Root Length ◽

Root Biomass ◽

Fine Root ◽

Fine Root Biomass ◽

Total Biomass ◽

Total N ◽

Northern Hardwood ◽

Production Values ◽

Fine Root Length

The dynamics of fine (<2.0 mm) roots were measured in two sugar maple (Acersaccharum Marsh.) dominated ecosystems (northern and southern sites) during 1989 and 1990 using a combination of minirhizotrons and destructive harvests of fine root biomass and N content. Greater than 50% of annual length production occurred before midsummer in both ecosystems, while the period of greatest mortality was from late summer through winter. About one third of annual fine root production and mortality occur simultaneously, with little observable change in total root length pools. Using fine root length dynamics to derive biomass production and mortality, we calculated annual biomass production values of approximately 8000 and 7300 kg•ha−1•year−1, respectively, at the southern and northern sites. Corresponding biomass mortality (i.e., turnover) values were 6700 and 4800 kg•ha−1•year−1, and total nitrogen returns to the soil from fine root mortality were 72 kg•ha−1•year−1 at the southern site and 54 kg•ha−1•year−1 at the northern site. Fine roots dominated total biomass and N litter inputs to the soil in both ecosystems, accounting for over 55% of total biomass and nearly 50% of total N returns. In both ecosystems, roots <0.5 mm comprised the bulk of fine root biomass and N pools, and the contribution of these roots to northern hardwood ecosystem carbon and nitrogen budgets may have been underestimated in the past.

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