scholarly journals Soil respiration and net ecosystem productivity in a chronosequence of hybrid poplar plantations

2020 ◽  
Vol 100 (4) ◽  
pp. 488-502
Author(s):  
Scott X. Chang ◽  
Zheng Shi ◽  
Barb R. Thomas
Keyword(s):  
Soil Respiration ◽  
Soil Temperature ◽  
Populus Deltoides ◽  
Hybrid Poplar ◽  
Stand Age ◽  
Net Ecosystem Productivity ◽  
Ecosystem Productivity ◽  
Short Rotation ◽  
C Dynamics ◽  
Woody Crop

Forest stand age can affect ecosystem carbon (C) cycling and net ecosystem productivity (NEP). In Canada, establishment of short-rotation plantations on previously agricultural lands has been ongoing, but the effect of stand development on soil respiration (Rs) and NEP in such plantations is poorly understood. These types of data are essential for constraining ecosystem models that simulate C dynamics over the rotation of a plantation. We studied Rs (including autotrophic, Ra, and heterotrophic, Rh) and NEP in 2008 and 2009 in a chronosequence of 5-, 8-, 14-, and 16-yr-old (ages in 2009) hybrid poplar (Populus deltoides × Populus × petrowskyana var. Walker) plantations in northern Alberta. The highest Rs and NEP were generally found in the 14-yr-old stand. Seasonal variations in Rs were similar among the plantations, with most of the variation explained by soil temperature at the 10 cm depth in 2008 with far less explained in 2009, a much drier year. In diurnal measurements, hysteresis was found between soil respiration and soil temperature, with the patterns of hysteresis different among stand ages. Soil respiration in the 14-yr-old plantation had the greatest sensitivity to temperature changes. Stand age did not affect the Rh:Rs ratio, whereas the NEP exhibited strong inter-annual variability. We conclude that stand age was a major factor affecting Rs and NEP, and such effects should be considered in empirical models used to simulate ecosystem C dynamics to evaluate potentials for C sequestration and the C source–sink relationship in short-rotation woody crop systems.

Comparison of soil respiration among three temperate forests in Changbai Mountains, China

2010 ◽  
Vol 40 (4) ◽  
pp. 788-795 ◽  
Author(s):  
Xu Wang ◽  
Yanling Jiang ◽  
Bingrui Jia ◽  
Fengyu Wang ◽  
Guangsheng Zhou
Keyword(s):  
Soil Respiration ◽  
Soil Temperature ◽  
Secondary Forest ◽  
Temperature Response ◽  
Stand Age ◽  
Changbai Mountains ◽  
Primary Forest ◽  
Plantation Forest ◽  
Successional Stage ◽  
Coniferous Plantation

CO2 efflux from forest soils is an important process in the global carbon cycle; however, effects of stand age and successional status remain uncertain. We compared soil respiration and its relationship to soil carbon content, forest floor mass, root biomass, soil temperature, and soil moisture content among three temperate forest ecosystems in Changbai Mountains, northeastern China, from 2003 to 2005. Forest types included an old-growth, mixed coniferous and broad-leaved primary forest (MN), a middle-aged, broad-leaved secondary forest (BL), and a young coniferous plantation forest (CP). Average annual soil CO2 efflux at BL (1477.9 ± 61.8 g C·m–2·year–1) was significantly higher than at CP (830.7 ± 48.7 g C·m–2·year–1) and MN (935.4 ± 53.3 g C·m–2·year–1). Differences in soil temperature among those sites were not statistically significant but contributed to the differences in annual CO2 efflux. In addition, the temperature response of soil CO2 efflux was higher at MN (Q10 = 2.78) than that at BL (Q10 = 2.17) and CP (Q10 = 2.02). Our results suggest that successional stage affects soil respiration by the differences in substrate quantity and quality, environmental conditions, and root respiration.

scholarly journals High-resolution forest carbon flux mapping and monitoring in the Pacific Northwest with time since disturbance and disturbance legacies inferred from remote sensing and inventory data

2016 ◽  
Author(s):  
Huan Gu ◽  
Christopher A. Williams ◽  
Bardan Ghimire ◽  
Feng Zhao ◽  
Chengquan Huang
Keyword(s):  
Remote Sensing ◽  
Pacific Northwest ◽  
Forest Inventory ◽  
Stand Age ◽  
Net Ecosystem Productivity ◽  
Fine Scale ◽  
Ecosystem Productivity ◽  
Inventory Data ◽  
Forest Inventory Data ◽  
The Pacific

Abstract. Assessment of forest carbon storage and uptake is central to understanding the role forests play in the global carbon cycle and policy-making aimed at mitigating climate change. Current U.S. carbon stocks and fluxes are monitored and reported at fine-scale regionally, or coarse-scale nationally. We proposed a new methodology of quantifying carbon uptake and release across forested landscapes in the Pacific Northwest (PNW) at a fine scale (30 m) by combining remote-sensing based disturbance year, disturbance type, and aboveground biomass with forest inventory data in a carbon modelling framework. Time since disturbance is a key intermediate determinant that aided the assessment of disturbance-driven carbon emissions and removals legacies. When a recent disturbance was detected, time since disturbance can be directly determined by remote sensing-derived disturbance products; and if not, time since last stand-clearing was inferred from remote sensing-derived 30 m biomass map and field inventory-derived species-specific biomass regrowth curves. Net ecosystem productivity (NEP) was further mapped based on carbon stock and flux trajectories that described how NEP changes with time following harvest, fire, or bark beetle disturbances of varying severity. Uncertainties from biomass map and forest inventory data were propagated by probabilistic sampling to provide a probabilistic, statistical distribution of stand age and NEP for each forest pixel. We mapped mean, standard deviation and statistical distribution of stand age and NEP at 30 m in the PNW region. Our map indicated a net ecosystem productivity of 5.2 Tg C y−1 for forestlands circa 2010 in the study area, with net uptake in relatively mature (> 24 year old) forests (13.6 Tg C y−1) overwhelming net negative NEP from tracts that have seen recent harvest (−6.4 Tg C y−1), fires (−0.5 Tg C y−1), and bark beetle outbreaks (−1.4 Tg C y−1). The approach will be applied to forestlands in other regions of the conterminous U.S. to advance a more comprehensive monitoring, mapping and reporting the carbon consequences of forest change across the U.S.

Morphological and physiological traits influencing biomass productivity in short-rotation coppice poplar

2004 ◽  
Vol 34 (7) ◽  
pp. 1488-1498 ◽  
Author(s):  
A M Rae ◽  
K M Robinson ◽  
N R Street ◽  
G Taylor
Keyword(s):  
Biomass Yield ◽  
Populus Deltoides ◽  
Hybrid Poplar ◽  
Biomass Productivity ◽  
Biomass Energy ◽  
Short Rotation Coppice ◽  
High Yield ◽  
Breeding Programs ◽  
Basal Diameter ◽  
Short Rotation

Fast-growing hybrid poplar (Populus spp.) have potential as a short-rotation coppice crop grown for biomass energy. This work identifies traits for fast growth studied in an American interspecific pedigree derived from Populus trichocarpa Torr. & A. Gray × Populus deltoides Marsh. grown in the United Kingdom for the first time. The biomass yield after the first coppice rotation was estimated to range from 0.04 to 23.68 oven-dried t·ha–1·year–1. This great range suggests that genotypes from this pedigree may be used to understand the genetic basis of high yield in short-rotation coppice, which would be advantageous for informing breeding programs for biomass crops. Relationships between stem, leaf, cell traits, and biomass yield were investigated. Partial least-squares analysis was used to order the traits by importance. The traits most influential on biomass were maximum stem height throughout the growing season, basal diameter, number of stems, and number of sylleptic branches, which showed high heritability, indicating excellent potential for breeding programs. The leaf traits, leaf area, number of leaves on the leading stem, and plastochron index were also associated with an increase in biomass, leading to a better understanding of this trait.

scholarly journals Carbon–nitrogen interactions in European forests and semi-natural vegetation – Part 2: Untangling climatic, edaphic, management and nitrogen deposition effects on carbon sequestration potentials

2020 ◽  
Vol 17 (6) ◽  
pp. 1621-1654 ◽  
Author(s):  
Chris R. Flechard ◽  
Marcel van Oijen ◽  
David R. Cameron ◽  
Wim de Vries ◽  
Andreas Ibrom ◽  
...  
Keyword(s):  
Carbon Sequestration ◽  
Nitrogen Deposition ◽  
C Sequestration ◽  
Forest Growth ◽  
Limiting Factors ◽  
Stand Age ◽  
Net Ecosystem Productivity ◽  
Growth Responses ◽  
Ecosystem Productivity ◽  
Forest Growth Model

Abstract. The effects of atmospheric nitrogen deposition (Ndep) on carbon (C) sequestration in forests have often been assessed by relating differences in productivity to spatial variations of Ndep across a large geographic domain. These correlations generally suffer from covariation of other confounding variables related to climate and other growth-limiting factors, as well as large uncertainties in total (dry + wet) reactive nitrogen (Nr) deposition. We propose a methodology for untangling the effects of Ndep from those of meteorological variables, soil water retention capacity and stand age, using a mechanistic forest growth model in combination with eddy covariance CO2 exchange fluxes from a Europe-wide network of 22 forest flux towers. Total Nr deposition rates were estimated from local measurements as far as possible. The forest data were compared with data from natural or semi-natural, non-woody vegetation sites. The response of forest net ecosystem productivity to nitrogen deposition (dNEP ∕ dNdep) was estimated after accounting for the effects on gross primary productivity (GPP) of the co-correlates by means of a meta-modelling standardization procedure, which resulted in a reduction by a factor of about 2 of the uncorrected, apparent dGPP ∕ dNdep value. This model-enhanced analysis of the C and Ndep flux observations at the scale of the European network suggests a mean overall dNEP ∕ dNdep response of forest lifetime C sequestration to Ndep of the order of 40–50 g C per g N, which is slightly larger but not significantly different from the range of estimates published in the most recent reviews. Importantly, patterns of gross primary and net ecosystem productivity versus Ndep were non-linear, with no further growth responses at high Ndep levels (Ndep > 2.5–3 g N m−2 yr−1) but accompanied by increasingly large ecosystem N losses by leaching and gaseous emissions. The reduced increase in productivity per unit N deposited at high Ndep levels implies that the forecast increased Nr emissions and increased Ndep levels in large areas of Asia may not positively impact the continent's forest CO2 sink. The large level of unexplained variability in observed carbon sequestration efficiency (CSE) across sites further adds to the uncertainty in the dC∕dN response.

scholarly journals Soil respiration of a Moso bamboo forest significantly affected by gross ecosystem productivity and leaf area index in an extreme drought event

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5747 ◽  
Author(s):  
Yuli Liu ◽  
Guomo Zhou ◽  
Huaqiang Du ◽  
Frank Berninger ◽  
Fangjie Mao ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Soil Respiration ◽  
Soil Temperature ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Moso Bamboo ◽  
Drought Event ◽  
Ecosystem Productivity ◽  
Area Index ◽  
Gross Ecosystem Productivity

Moso bamboo has large potential to alleviate global warming through carbon sequestration. Since soil respiration (Rs) is a major source of CO2 emissions, we analyzed the dynamics of soil respiration (Rs) and its relation to environmental factors in a Moso bamboo (Phllostachys heterocycla cv. pubescens) forest to identify the relative importance of biotic and abiotic drivers of respiration. Annual average Rs was 44.07 t CO2 ha−1 a−1. Rs correlated significantly with soil temperature (P < 0.01), which explained 69.7% of the variation in Rs at a diurnal scale. Soil moisture was correlated significantly with Rs on a daily scale except not during winter, indicating it affected Rs. A model including both soil temperature and soil moisture explained 93.6% of seasonal variations in Rs. The relationship between Rs and soil temperature during a day showed a clear hysteresis. Rs was significantly and positively (P < 0.01) related to gross ecosystem productivity and leaf area index, demonstrating the significance of biotic factors as crucial drivers of Rs.

scholarly journals High-resolution mapping of time since disturbance and forest carbon flux from remote sensing and inventory data to assess harvest, fire, and beetle disturbance legacies in the Pacific Northwest

2016 ◽  
Vol 13 (22) ◽  
pp. 6321-6337 ◽  
Author(s):  
Huan Gu ◽  
Christopher A. Williams ◽  
Bardan Ghimire ◽  
Feng Zhao ◽  
Chengquan Huang
Keyword(s):  
Pacific Northwest ◽  
Forest Inventory ◽  
Carbon Flux ◽  
Forest Carbon ◽  
Stand Age ◽  
Net Ecosystem Productivity ◽  
Ecosystem Productivity ◽  
Inventory Data ◽  
Forest Inventory Data ◽  
The Pacific

Abstract. Accurate assessment of forest carbon storage and uptake is central to policymaking aimed at mitigating climate change and understanding the role forests play in the global carbon cycle. Disturbances have highly diverse impacts on forest carbon dynamics, making them a challenge to quantify and report. Time since disturbance is a key intermediate determinant that aids the assessment of disturbance-driven carbon emissions and removals legacies. We propose a new methodology of quantifying time since disturbance and carbon flux across forested landscapes in the Pacific Northwest (PNW) at a fine scale (30 m) by combining remote sensing (RS)-based disturbance year, disturbance type, and above-ground biomass with forest inventory data. When a recent disturbance is detected, time since disturbance can be directly determined by combining three RS-derived disturbance products, or time since the last stand clearing can be inferred from a RS-derived 30 m biomass map and field inventory-derived species-specific biomass accumulation curves. Net ecosystem productivity (NEP) is further mapped based on carbon stock and flux trajectories derived from the Carnegie-Ames-Stanford Approach (CASA) model in our prior work that described how NEP changes with time following harvest, fire, or bark beetle disturbances of varying severity. Uncertainties from biomass map and forest inventory data were propagated by probabilistic sampling to provide a statistical distribution of stand age and NEP for each forest pixel. We mapped mean, standard deviation, and statistical distribution of stand age and NEP at 30 m in the PNW region. Our map indicated a net ecosystem productivity of 5.9 Tg C yr−1 for forestlands circa 2010 in the study area, with net uptake in relatively mature (> 24 years old) forests (13.6 Tg C yr−1) overwhelming net negative NEP from tracts that had recent harvests (−6.4 Tg C yr−1), fires (−0.5 Tg C yr−1), and bark beetle outbreaks (−0.8 Tg C yr−1). The approach will be applied to forestlands in other regions of the conterminous US to advance a more comprehensive monitoring, mapping, and reporting of the carbon consequences of forest change across the US.

Forecasting the deployment of short-rotation intensive culture of willow or hybrid poplar: Insights from a Delphi study

2014 ◽  
Vol 44 (5) ◽  
pp. 422-431 ◽  
Author(s):  
Sylvain Masse ◽  
Pierre P. Marchand ◽  
Michèle Bernier-Cardou
Keyword(s):  
Delphi Study ◽  
Methodological Approach ◽  
Hybrid Poplar ◽  
Agroforestry Systems ◽  
Intensive Culture ◽  
Short Rotation ◽  
Production Technologies ◽  
Policies And Programs ◽  
Woody Crop

Short-rotation intensive culture (SRIC) of willow (Salix spp.) or hybrid poplar (Populus spp.) is currently at a precommercial stage with a potential to be applied economically across important areas to produce lignocellulosic biomass and environmental services in Canada. A two-round Delphi survey was conducted among 50 experts to assess the future deployment of SRIC in this country. The total area in 10 years (2011 base year) was forecasted as 1330, 4100, and 11 400 ha under pessimistic, realistic, and optimistic scenarios, respectively. The deployment of SRIC in the next decade depends mainly on the development of the demand for SRIC biomass and services, that of production technologies, and the establishment of policies and programs promoting its application. In the short term, research and development (R&D) and policy initiatives should be funded or implemented by various stakeholders to facilitate the deployment of the system. On average, respondents deemed that the potential for long-term (20 years) deployment of SRIC in Canada was good. Some of the conclusions and the methodological approach of this study could apply to short-rotation woody crop systems and to agroforestry systems in Canada and elsewhere.

scholarly journals Mullahingamise sesoonne dünaamika kuusikute aegreas / Seasonal dynamics of soil respiration in a chronosequence of the Norway spruce stands

2011 ◽  
Vol 54 (1) ◽  
pp. 5-17 ◽  
Author(s):  
Mai Kukumägi ◽  
Veiko Uri ◽  
Olevi Kull
Keyword(s):  
Soil Moisture ◽  
Soil Respiration ◽  
Soil Temperature ◽  
Norway Spruce ◽  
Respiration Rate ◽  
Stand Age ◽  
Exponential Relationship ◽  
Climate Conditions ◽  
Dry Conditions ◽  
The Individual

Abstract. Soil respiration resulting from microbial and root respiration is a major component of the forest carbon cycle. The response of soil respiration to varying environmental factors (soil temperature and soil moisture) was studied in a Norway spruce chronosequence composed of four age classes (4, 27, 36, and 84 year old) on Gleyic Podzol. Soil respiration was measured monthly with closed dynamic chamber system, soil temperature and soil moisture were measured simultaneously. Mean soil respiration rate averaged over three years was 3.3 μmol CO2 m-2s-1, ranging from 0.6 to 5.4 μmol CO2 m-2s-1, with the maximum occurring in August and the minimum in December. Stand age had a significant effect on soil respiration: the highest respiration rate was found in 27-year-old stand. Over three years an exponential relationship between soil respiration and soil temperature accounted for 68-81% of the seasonal variation, Q10 (the factor by which the respiration rate differs for a temperature interval of 10 °C) for the individual stands ranged between 4.4 and 5.4. The influence of soil moisture content on soil respiration was weak and revealed in dry conditions only. The results of this study can be used to help understand and predict the effect of harvest on soil respiration and how the respiration might respond to changing climate conditions.

Sign in / Sign up

Export Citation Format

Share Document