Effects of different planting configurations and clones on biomass and carbon storage of a 12-year-old poplar ecosystem in southern China

The main objective of this study was to compare the effects of two densities (278 stems·ha−1 with two spacings of 6 m × 6 m or 4.5 m × 8 m, 400 stems·ha−1 with two spacings of 5 m × 5 m or 3 m × 8 m) and three poplar clones (NL95, NL895, and NL797) on productivity and carbon (C) sequestration of poplar ecosystems. The results showed that planting density significantly affected the biomass of a single tree. The mean tree biomass of clone NL95 was higher in all spacings than that of the other clones, with a significant difference for the 6 m × 6 m spacing. The biomass of poplar trees ranged from 78.9 to 110.3 Mg·ha−1, with the highest tree biomass observed in the square configuration. Soil C concentration (0–100 cm) increased after 12 years of management. Soil C storage ranged from 138.1 to 164.3 Mg C·ha−1, and the highest soil C storage was in the NL797 poplar plantation with 6 m × 6 m spacing. Our results suggested that clones NL95 and NL797 should be chosen for planting, with a planting density of 278 stems·ha−1 and spacing of 6 m × 6 m.

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Higher stand densities can promote soil carbon storage after conversion of temperate mixed natural forests to larch plantations

European Journal of Forest Research ◽

10.1007/s10342-020-01346-9 ◽

2020 ◽

Author(s):

Meng Na ◽

Xiaoyang Sun ◽

Yandong Zhang ◽

Zhihu Sun ◽

Johannes Rousk

Keyword(s):

Forest Management ◽

Soil Carbon ◽

Stand Density ◽

C Sequestration ◽

Tree Density ◽

Natural Forests ◽

Soil C ◽

C Storage ◽

Soil C Storage ◽

Soil C Sequestration

AbstractSoil carbon (C) reservoirs held in forests play a significant role in the global C cycle. However, harvesting natural forests tend to lead to soil C loss, which can be countered by the establishment of plantations after clear cutting. Therefore, there is a need to determine how forest management can affect soil C sequestration. The management of stand density could provide an effective tool to control soil C sequestration, yet how stand density influences soil C remains an open question. To address this question, we investigated soil C storage in 8-year pure hybrid larch (Larix spp.) plantations with three densities (2000 trees ha−1, 3300 trees ha−1 and 4400 trees ha−1), established following the harvesting of secondary mixed natural forest. We found that soil C storage increased with higher tree density, which mainly correlated with increases of dissolved organic C as well as litter and root C input. In addition, soil respiration decreased with higher tree density during the most productive periods of warm and moist conditions. The reduced SOM decomposition suggested by lowered respiration was also corroborated with reduced levels of plant litter decomposition. The stimulated inputs and reduced exports of C from the forest floor resulted in a 40% higher soil C stock in high- compared to low-density forests within 8 years after plantation, providing effective advice for forest management to promote soil C sequestration in ecosystems.

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Root biomass responses to elevated CO<sub>2</sub> limit soil C sequestration in managed grasslands

Biogeosciences Discussions ◽

10.5194/bgd-9-357-2012 ◽

2012 ◽

Vol 9 (1) ◽

pp. 357-386 ◽

Cited By ~ 1

Author(s):

W. M. A. Sillen ◽

W. I. J. Dieleman

Keyword(s):

Elevated Co2 ◽

Nitrogen Fertilization ◽

Root Biomass ◽

Terrestrial Ecosystems ◽

C Sequestration ◽

Soil C ◽

C Storage ◽

Co2 Concentrations ◽

Soil C Storage ◽

Co2 Elevation

Abstract. Elevated atmospheric CO2 levels and increasing nitrogen deposition both stimulate plant production in terrestrial ecosystems. Moreover, nitrogen deposition could alleviate an increasing nitrogen limitation experienced by plants exposed to elevated CO2 concentrations. However, an increased rate of C flux through the soil compartment as a consequence of elevated CO2 concentrations has been suggested to limit C sequestration in terrestrial ecosystems, questioning the potential for terrestrial C uptake to mitigate the increasing atmospheric CO2 concentrations. Our study used data from 69 published studies to investigate whether CO2 elevation and/or nitrogen fertilization could induce an increased carbon storage in grasslands, and considered the influence of management practices involving biomass removal or irrigation on the elevated CO2 effects. Our results confirmed a positive effect of elevated CO2 levels and nitrogen fertilization on plant growth, but revealed that N availability is essential for the increased C influx under elevated CO2 to propagate into belowground C pools. However, moderate nutrient additions also promoted decomposition processes in elevated CO2, reducing the potential for increased soil C storage. An important role in the soil carbon response to elevated CO2 was attributed to the root response, since there was a lower potential for increases in soil C content when root biomass was more responsive to CO2 elevation. Future elevated CO2 concentrations and increasing N deposition might thus increase C storage in plant biomass, but the potential for increased soil C storage is limited.

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Nonlinear turnover rates of soil carbon following cultivation of native grasslands and subsequent afforestation of croplands

10.5194/soil-2021-5 ◽

2021 ◽

Author(s):

Guillermo Hernandez-Ramirez ◽

Thomas J. Sauer ◽

Yury G. Chendev ◽

Alexander N. Gennadiev

Keyword(s):

Land Use ◽

C Sequestration ◽

Tree Planting ◽

Lag Phase ◽

Turnover Rates ◽

Soil C ◽

C Storage ◽

Soil C Storage ◽

Changes Over Time ◽

Over Time

Abstract. Land use conversions can strongly impact soil organic matter (SOM) storage, which creates paramount opportunities for sequestering atmospheric carbon into the soil. It is known that land uses such as annual cropping and afforestation can decrease and increase SOM, respectively; however, the rates of these changes over time remain elusive. This study focused on extracting the kinetics (k) of turnover rates that describe these long-term changes in soil C storage and also quantifying the sources of soil C. We used topsoil organic carbon density and δ13C isotopic composition data from multiple chronosequences and paired sites in Russia and United States. Reconstruction of soil C storage trajectory over 250 years following conversion from native grassland to continual annual cropland revealed a C depletion rate of 0.010 years−1 (first-order k rate constant), which translates into a mean residence time (MRT) of 100 years (R2 ≥ 0.90). Conversely, soil C accretion was observed over 70 years following afforestation of annual croplands at a much faster k rate of 0.055 years−1. The corresponding MRT was only 18 years (R2 = 0.997) after a lag phase of 5 years. Over these 23 years of afforestation, trees contributed 14 Mg C Ha−1 to soil C accrual in the 0 to 15 cm depth increment. This tree-C contribution reached 22 Mg C Ha−1 at 70 years after tree planting. Over these 70 years of afforestation, the proportion of tree-C to whole soil C increased to reach a sizeable 79 %. Furthermore, assuming steady state of soil C in the adjacent croplands, we also estimated that 45 % of the prairie-C existent at time of tree planting was still present in the afforested soils 70 years later. As intrinsic of k modelling, the derived turnover rates that represent soil C changes over time are nonlinear. Soil C changes were much more dynamic during the first decades following a land use conversion than afterwards when the new land use system approached equilibrium. Collectively, results substantiated that C sequestration in afforested lands is a suitable means to proactively mitigate escalating climate change within a typical person's lifetime, as indicated by MRTs of few decades.

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Microbial Mechanisms Mediating Increased Soil C Storage under Elevated Atmospheric N Deposition

Applied and Environmental Microbiology ◽

10.1128/aem.03156-12 ◽

2012 ◽

Vol 79 (4) ◽

pp. 1191-1199 ◽

Cited By ~ 47

Author(s):

Sarah D. Eisenlord ◽

Zachary Freedman ◽

Donald R. Zak ◽

Kai Xue ◽

Zhili He ◽

...

Keyword(s):

Forest Floor ◽

Forest Ecosystems ◽

N Deposition ◽

Fungal Communities ◽

Functional Genes ◽

Atmospheric N Deposition ◽

Soil C ◽

C Storage ◽

Genes Encoding ◽

Soil C Storage

ABSTRACTFuture rates of anthropogenic N deposition can slow the cycling and enhance the storage of C in forest ecosystems. In a northern hardwood forest ecosystem, experimental N deposition has decreased the extent of forest floor decay, leading to increased soil C storage. To better understand the microbial mechanisms mediating this response, we examined the functional genes derived from communities of actinobacteria and fungi present in the forest floor using GeoChip 4.0, a high-throughput functional-gene microarray. The compositions of functional genes derived from actinobacterial and fungal communities was significantly altered by experimental nitrogen deposition, with more heterogeneity detected in both groups. Experimental N deposition significantly decreased the richness and diversity of genes involved in the depolymerization of starch (∼12%), hemicellulose (∼16%), cellulose (∼16%), chitin (∼15%), and lignin (∼16%). The decrease in richness occurred across all taxonomic groupings detected by the microarray. The compositions of genes encoding oxidoreductases, which plausibly mediate lignin decay, were responsible for much of the observed dissimilarity between actinobacterial communities under ambient and experimental N deposition. This shift in composition and decrease in richness and diversity of genes encoding enzymes that mediate the decay process has occurred in parallel with a reduction in the extent of decay and accumulation of soil organic matter. Our observations indicate that compositional changes in actinobacterial and fungal communities elicited by experimental N deposition have functional implications for the cycling and storage of carbon in forest ecosystems.

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Biomass and carbon storage in an age-sequence of Acacia mangium plantation forests in Southeastern region, Vietnam

Forest Systems ◽

10.5424/fs/2020292-16685 ◽

2020 ◽

Vol 29 (2) ◽

pp. e009

Author(s):

Cuong Levan ◽

Hung Buimanh ◽

Bolanle-Ojo Oluwasanmi Tope ◽

Xiaoniu Xu ◽

Thanh Nguyenminh ◽

...

Keyword(s):

Carbon Storage ◽

Acacia Mangium ◽

Understory Vegetation ◽

Stand Age ◽

Tree Biomass ◽

Organic C ◽

Soil C ◽

C Storage ◽

Age Sequence ◽

Southeastern Region

Aim of the study: The major objective of this study was to estimate the biomass increment and carbon (C) storage of the main ecosystem components in an age-sequence of three Acacia mangium plantation stands.Area of study: Chang Riec Historical - Cultural Forest, Southeastern region, Vietnam.Material and methods: In order to assess the biomass of different tree components, 36 trees with diameter at breast height ranging from 13.38 to 22.87 cm were harvested from the different aged stands. Biomasses of understory (shrubs and herbs), and litter were also determined. Carbon storage in the trees and understory biomass, litter, and mineral soil (0-50 cm) were determined by analyzing the C content of each compartment.Main results: The biomass in trees, understory vegetation, litter, and ecosystem increased with stand age. Soil C represented 61.99% of the total, aboveground tree biomass C made up 26.73%, belowground tree biomass C accounted for 7.01%, and litter comprised 2.96%, whereas only a small amount (1.30%) was associated with understory vegetation. The average C content of total tree (47.97%) was higher than those of understory and litter. Soil organic C stock in the top 50 cm depth in 4-, 7- and 11-year-old stands of A. mangium were 86.86, 126.88 and 140.94 Mg. C ha-1 respectively. Soil C concentration decreased continually with increasing soil depth. Total C storage of three planted forests ranged from 131.36 to 255.86 Mg. C ha-1, of which 56.09 - 67.61% of C storage was in the soil and 26.88 - 40.40% in the trees.Research highlights: These results suggest that A. mangium is a promising afforestation tree species with fast growing, high biomass accumulation and high C sequestration potential.Keywords: Acacia mangium plantations; Biomass; Ecosystem carbon storage; Age-sequence; Vietnam.

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Reforestation can sequester two petagrams of carbon in US topsoils in a century

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1719685115 ◽

2018 ◽

Vol 115 (11) ◽

pp. 2776-2781 ◽

Cited By ~ 33

Author(s):

Lucas E. Nave ◽

Grant M. Domke ◽

Kathryn L. Hofmeister ◽

Umakant Mishra ◽

Charles H. Perry ◽

...

Keyword(s):

National Level ◽

Mineral Soil ◽

C Sequestration ◽

The United States ◽

Forest Sector ◽

Soil C ◽

C Storage ◽

C Stocks ◽

The Us ◽

Land Use And Management

Soils are Earth’s largest terrestrial carbon (C) pool, and their responsiveness to land use and management make them appealing targets for strategies to enhance C sequestration. Numerous studies have identified practices that increase soil C, but their inferences are often based on limited data extrapolated over large areas. Here, we combine 15,000 observations from two national-level databases with remote sensing information to address the impacts of reforestation on the sequestration of C in topsoils (uppermost mineral soil horizons). We quantify C stocks in cultivated, reforesting, and natural forest topsoils; rates of C accumulation in reforesting topsoils; and their contribution to the US forest C sink. Our results indicate that reforestation increases topsoil C storage, and that reforesting lands, currently occupying >500,000 km2 in the United States, will sequester a cumulative 1.3–2.1 Pg C within a century (13–21 Tg C·y−1). Annually, these C gains constitute 10% of the US forest sector C sink and offset 1% of all US greenhouse gas emissions.

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Assessment of soil carbon storage and nutrient contents in some wetlands soils of the northeastern region of Bangladesh

Dhaka University Journal of Biological Sciences ◽

10.3329/dujbs.v30i1.51815 ◽

2021 ◽

Vol 30 (1) ◽

pp. 115-124

Author(s):

Arafat Rahman ◽

MS Islam ◽

Humyra B Murshed ◽

MJ Uddin ◽

ASM Mohiuddin ◽

...

Keyword(s):

Soil Depth ◽

Integrated Management ◽

Management Approach ◽

Wetland Soils ◽

Soil Layers ◽

Soil C ◽

Nutrient Contents ◽

C Storage ◽

Soil C Storage ◽

Land Types

An investigation was carried out in four designated wetlands to assess soil organic carbon (SOC) storage and evaluate soil nutrients of the northeastern Sylhet basin of Bangladesh. SOC storage was the highest in the Nikli wetland (4.1 Tg), followed by Hakaluki (4.0 Tg), Hail (2.8 Tg) and Balai wetland soils (2.6 Tg) at 100 cm depths. It is found that the total soil C storage across the medium low land (MLL) and low land (LL) sites covering the four wetlands of the Sylhet basin is about 13.5Tg. C storage across the MLL and LL sites at 100 cm depths was estimated about 5.1Tg and 8.4Tg respectively. It is found that SOC storage was higher in the low land sites in contrast to medium low land sites. The soil property varies depending on land types, soil depths and spatial distributions. Among the investigated wetland soils, Hakaluki wetland stored higher amount of SOC in the deeper soil layers whereas an inverse relationship between soil depth and SOC storage was noted for rest of the wetlands. It is apprehended that SOC storage thus gradually lessening in greater magnitude due to climate change and other anthropogenic reasons. An integrated management approach should be developed to restore the SOC sink. Dhaka Univ. J. Biol. Sci. 30(1): 115-124, 2021 (January)

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