Plant Carbon Storage Research Articles

Ecosystem multifunctionality is more related to the indirect effects than to the direct effects of human management in China's drylands

Drylands provide a wide range of important ecosystem functions but are sensitive to environmental changes, especially human management. Two major land use types of drylands are grasslands and croplands, which are influenced by intensive grazing activities and agricultural management, respectively. However, little is known about whether the ecosystem functioning of these two land use types is predominated affected by human management, or environmental factors (intrinsic environmental factors and factors modified by human management). This limits our understanding of the ecosystem functions under intensive human management in drylands. Here we reported a study where we collected data from 40 grassland and 30 cropland sites along an extensive aridity gradient in China's drylands to quantify the effects of human management intensity, intrinsic environmental factors (i.e., aridity), and environmental factors modified by human management (i.e., soil bulk density and plant density) on specific ecosystem functions (ecosystem multifunctionality, productivity, carbon storage, soil water, and soil nutrients). We found that the relative importance of each function differed between croplands and grasslands. Ecosystem functions varied with human management intensity, with lower productivity and plant carbon storage in grasslands under high grazing intensity than un-grazed, while multifunctionality and carbon storage increased with greater fertilization only in arid croplands. Furthermore, among environmental factors, soil bulk density had the greatest negative effects, which directly reduced multifunctionality in grasslands and indirectly reduced multifunctionality in croplands via suppressing crop density. Crop density was the major environmental factor that positively related to multifunctionality in croplands. However, these effects would be exacerbated with increasing aridity. Our study demonstrated that compared with the direct impacts of human management, environmental factors modified by human management (e.g., soil bulk density) are the major drivers of ecosystem functions, indicating that improving soil structure by alleviating human interferences (e.g., reducing livestock trampling) would be an effective way to restore ecosystem functions in drylands under global warming and drying.

Plant diversity decreases greenhouse gas emissions by increasing soil and plant carbon storage in terrestrial ecosystems.

The decline in global plant diversity has raised concerns about its implications for carbon fixation and global greenhouse gas emissions (GGE), including carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). Therefore, we conducted a comprehensive meta-analysis of 2103 paired observations, examining GGE, soil organic carbon (SOC) and plant carbon in plant mixtures and monocultures. Our findings indicate that plant mixtures decrease soil N2O emissions by 21.4% compared to monocultures. No significant differences occurred between mixtures and monocultures for soil CO2 emissions, CH4 emissions or CH4 uptake. Plant mixtures exhibit higher SOC and plant carbon storage than monocultures. After 10 years of vegetation development, a 40% reduction in species richness decreases SOC content and plant carbon storage by 12.3% and 58.7% respectively. These findings offer insights into the intricate connections between plant diversity, soil and plant carbon storage and GGE-a critical but previously unexamined aspect of biodiversity-ecosystem functioning.

Carbon Sequestration in Sugarcane Plant-soil System as Influenced by Nutrient Integration Practices under Indo-Gangetic Plains of India

Sugarcane is a multi-purpose crop. The capability of sugarcane crop to sequestrate carbon into soil and plant is of great importance. Under this study the carbon sequestration in planted sugarcane and their rhizospheric soil under different nutrient management practices was assessed. As IPCC reported, that the rising temperature of earth surface resulted of GHGs emission which causes global warming. In order to stabilize the global temperature, the anthropogenic CO2 has to be mitigated to a significant level and the surplus atmospheric CO2 in plants and soil has to be sunk, under this circumstance, sugarcane cultivation plays pivotal role in utilising CO2 since it is a C4 plant having high efficiency of utilising CO2 during photosynthesis. There is another intervention might be enhancing the CO2 capture by changing the nutrient management practices which enhances chlorophyll synthesis by the way of increasing nitrogen efficiency in sugarcane. The different treatment composition enhances photosynthesis where more CO2 has been captured. Thus the sugarcane crop and rhizospheric soils act as important carbon sinks in decarbonisation of atmosphere that ultimately reduces carbon level and causes the global cooling. Soil Properties and Carbon Storage: The results showed that soil physical properties and chemical properties were significantly differed among treatments due to application of different organic amendments over control. Soil organic carbon (SOC) was analysed which ranges from 0.47 to 0.67%. The different organic amendments treatments had a considerable effect on soil bulk density and porosity with significant improvement in soil carbon storage. Plant Carbon Storage: The carbon stocks in different sugarcane plant parts, including roots, shoots and leaves were significantly different. The highest amount of carbon stock was found in leaves (877.08 kg ha-1) under T6 followed by roots (668.74 kg ha-1) in T2 and carbon stock in shoots (422.77 kg ha-1) in T5 showing that 30.41% and 107.58% more carbons were stored in the leaves as compared to the roots and shoots while in roots 58.18% more carbon stored in comparison to shoots. The total carbon storage in sugarcane biomass including aboveground parts and belowground part i.e. roots, in different treatment was significantly different. The mean value of carbon stored in the aboveground parts (leaves and stalks) was significantly higher (1239.65 kg ha-1) than that of underground plant part (621.73 kg ha-1) (roots). The results showed that the sugarcane farming practices have promising effect for carbon sequestration and consequently enhancing the mitigation of climate change impacts.

Functional diversity and carbon storage of plant community elevation patterns and carbon accumulation mechanisms in desert shrubland of Yanqi Hola Mountain, China

Exploring the distribution characteristics of plant community functional diversity, functional traits and plant and soil carbon stocks along elevation and the effects of functional diversity and functional traits on carbon stocks is of great significance for revealing the distribution characteristics of plant community functional diversity and carbon stocks in the desert area and understanding the carbon accumulation mechanism. In this study, we took the leaf functional traits of plant community species and the carbon stocks of plants and soils of sample plots in the pre-Hola Mountain desert area as the research objects and explored their altitudinal distribution characteristics and their interrelationships. The results showed that (1) the plant carbon storage capacity of the shrub - herb association was the strongest, and the soil carbon storage capacity of the herb association was the strongest. (2) Functional richness and plant carbon storage capacity tended to increase and then decrease with elevation, while functional evenness and leaf phosphorus content tended to decrease and then increase with elevation. Functional dispersion, leaf water content, chlorophyll content, leaf carbon, nitrogen content, and soil carbon stock all showed a gradual increase with elevation, and the total carbon stock gradually increased with elevation in the middle and low elevation areas (1200–1800 m), and showed a wave-like change in the high elevation areas (1800–2400 m). (3) The accumulation of soil carbon stocks in the study area is mainly dominated by the “mass ratio hypothesis”, while the accumulation of plant carbon stocks is mainly dominated by the “ecological niche complementarity hypothesis”, and plant and soil carbon stocks are mainly affected by the specific leaf area and the content of carbon, nitrogen, and phosphorus in leaves.

Microbial communities and functions changed in rhizosphere soil of Pinus massoniana provenances with different carbon storage.

The average carbon storage of Pinus massoniana is much higher than the average carbon storage of Chinese forests, an important carbon sink tree species in subtropical regions of China. However, there are few studies on the differences in rhizosphere microorganisms of P. massoniana with different carbon storages. To clarify the relationships between plant carbon storage level, environmental parameters and microbial community structure, we identified three carbon storage levels from different P. massoniana provenances and collected rhizosphere soil samples. We determined chemical properties of soil, extracellular enzyme activity, and microbial community structures at different carbon storage levels and examined how soil factors affect rhizosphere microorganisms under different carbon storage levels. The results revealed that soil organic carbon (SOC), nitrate nitrogen (NO3--N), ammonium nitrogen (NH4+-N) contents all increased with increasing carbon storage levels, while pH decreased accordingly. In contrast, the available phosphorus (AP) content did not change significantly. The soil AP content was within the range of 0.91 ~ 1.04 mg/kg. The microbial community structure of P. massoniana changed with different carbon storage, with Acidobacteria (44.27%), Proteobacteria (32.57%), and Actinobacteria (13.43%) being the dominant bacterial phyla and Basidiomycota (73.36%) and Ascomycota (24.64%) being the dominant fungal phyla across the three carbon storage levels. Soil fungi were more responsive to carbon storage than bacteria in P. massoniana. C/N, NH4+-N, NO3--N, and SOC were the main drivers (p < 0.05) of changes in rhizosphere microbial communities. The results revealed that in the rhizosphere there were significant differences in soil carbon cycle and microorganism nutrient preferences at different carbon storages of P. massoniana provenance, which were significantly related to the changes in rhizosphere microbial community structure. Jiangxi Anyuan (AY) provenance is more suitable for the construction of high carbon storage plantation.

Dynamical systems for plant carbon storage: describing complex reserve dynamics from simple fluctuations in photosynthesis and carbon allocation.

Dynamical systems for plant carbon storage: describing complex reserve dynamics from simple fluctuations in photosynthesis and carbon allocation.

Nitrogen and water availability control plant carbon storage with warming

Plants may slow global warming through enhanced growth, because increased levels of photosynthesis stimulate the land carbon (C) sink. However, how climate warming affects plant C storage globally and key drivers determining the response of plant C storage to climate warming remains unclear, causing uncertainty in climate projections. We performed a comprehensive meta-analysis, compiling 393 observations from 99 warming studies to examine the global patterns of plant C storage responses to climate warming and explore the key drivers. Warming significantly increased total biomass (+8.4 %), aboveground biomass (+12.6 %) and belowground biomass (+10.1 %). The effect of experimental warming on plant biomass was best explained by the availability of soil nitrogen (N) and water. Across the entire dataset, warming-induced changes in total, aboveground and belowground biomass all positively correlated with soil C:N ratio, an indicator of soil N availability. In addition, warming stimulated plant biomass more strongly in humid than in dry ecosystems, and warming tended to decrease root:shoot ratios at high soil C:N ratios. Together, these results suggest dual controls of warming effects on plant C storage; warming increases plant growth in ecosystems where N is limiting plant growth, but it reduces plant growth where water availability is limiting plant growth.

Dynamic estimates of tree carbon storage and shade in Mediterranean urban areas

To highlight the ecosystem value of trees in the urban environment an EU's funding instrument for the environment and climate action – LIFE Project – was undertaken involving four Mediterranean cities as study cases: Thessaloniki in Greece, Cascais in Portugal, and Perugia and Bologna in Italy. The methodology utilized to evaluate plant carbon storage and shade areas highlighted the usefulness of gathering data about both the current urban green asset in the Project's investigated areas and future potential performances of the same asset to evaluate its efficiency in the forthcoming decades (2030–2050). The lower future potential of some cities for CO2 storage can be attributed to having older 'green assets' in comparison to other municipalities. A projection over the next 30 years on the basis of census results in the 4 studied areas highlighted the potential of some green areas characterised by the presence of efficient carbon storage tree species (high-growing broadleaf plants) while still small in size. &lt;br/&gt;The main objective of this study was to present both the current urban green asset carbon storage potential in the studied areas and also its future potential efficiency. Another aim of the work was to develop tree growth curves in urban areas, not only to estimate tree volumes but also to estimate the present and future shade areas related to woody plants' presence. &lt;br/&gt;With regard to CO2 storage simulation, the research highlighted the potential of green areas in Perugia that present tree species particularly efficient at carbon storage yet still small in size. Conversely, the lowest value presented by the species recorded in Cascais was influenced by the predominance of Cupressus sempervirens and Pinus pinea : two species not particularly efficient and large in size with average DBH values above 50 cm.

Decadal variation in CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; fluxes and its budget in a wheat and maize rotation cropland over the North China Plain

Abstract. Carbon sequestration in agroecosystems has great potential to mitigate global greenhouse gas emissions. To assess the decadal trend of CO2 fluxes of an irrigated wheat–maize rotation cropland over the North China Plain, the net ecosystem exchange (NEE) with the atmosphere was measured by using an eddy covariance system from 2005 to 2016. To evaluate the detailed CO2 budget components of this representative cropland, a comprehensive experiment was conducted in the full 2010–2011 wheat–maize rotation cycle by combining the eddy covariance NEE measurements, plant carbon storage samples, and a soil respiration experiment that differentiated between heterotrophic and below-ground autotrophic respirations. Over the past decade (from 2005 to 2016), the cropland exhibited a statistically nonsignificant decreasing carbon sequestration capacity; the average of total NEE, gross primary productivity (GPP), and ecosystem respiration (ER), respectively, were −364, 1174, and 810 gC m−2 for wheat and −136, 1008, and 872 gC m−2 for maize. The multiple regression revealed that air temperature and groundwater depth showed pronounced correlations with the CO2 fluxes for wheat. However, in the maize season, incoming shortwave radiation and groundwater depth showed pronounced correlations with CO2 fluxes. For the full 2010–2011 agricultural cycle, the CO2 fluxes for wheat and maize were as follows: for NEE they were −438 and −239 gC m−2, for GPP 1078 and 780 gC m−2, for ER 640 and 541 gC m−2, for soil heterotrophic respiration 377 and 292 gC m−2, for below-ground autotrophic respiration 136 and 115 gC m−2, and for above-ground autotrophic respiration 128 and 133 gC m−2. The net biome productivity was 59 gC m−2 for wheat and 5 gC m−2 for maize, indicating that wheat was a weak CO2 sink and maize was close to CO2 neutral to the atmosphere for this agricultural cycle. However, when considering the total CO2 loss in the fallow period, the net biome productivity was −40 gC m−2 yr−1 for the full 2010–2011 cycle, implying that the cropland was a weak CO2 source. The investigations of this study showed that taking cropland as a climate change mitigation tool is challenging and that further studies are required for the CO2 sequestration potential of croplands.

Woody plant encroachment may decrease plant carbon storage in grasslands under future drier conditions

Abstract Aims Woody plants are widely distributed in various grassland types along the altitudinal/climatic gradients in Xinjiang, China. Considering previously reported change in carbon (C) storage following woody plant encroachment in grasslands and the mediating effect of climate on this change, we predicted that a positive effect of woody plants on plant C storage in semiarid grasslands may revert to a negative effect in arid grasslands. We first investigated the spatial variation of aboveground C (AGC) and belowground C (BGC) storage among grassland types and then tested our prediction. Methods We measured the living AGC storage, litter C (LC) and BGC storage of plants in two physiognomic types, wooded grasslands (aboveground biomass of woody plants at least 50%) and pure grasslands without woody plants in six grassland types representing a gradient form semiarid to arid conditions across Xinjiang. Important Findings Living AGC, LC, BGC and total plant C storage increased from desert to mountain meadows. These increases could also be explained by increasing mean annual precipitation (MAP) or decreasing mean annual temperature (MAT), suggesting that grassland types indeed represented an aridity gradient. Woody plants had an effect on the plant C storage both in size and in distribution relative to pure grasslands. The direction and strength of the effect of woody plants varied with grassland types due to the mediating effect of the climate, with wetter conditions promoting a positive effect of woody plants. Woody plants increased vegetation-level AGC through their high AGC relative to herbaceous plants. However, more negative effects of woody plants on herbaceous plants with increasing aridity led to a weaker increase in the living AGC in arid desert, steppe desert and desert steppe than in the less arid other grassland types. Under greater aridity (lower MAP and higher MAT), woody plants allocated less biomass to roots and had lower BGC and had a more negative impact on herbaceous plant production, thereby reducing vegetation-level BGC in the desert, steppe desert and desert steppe. In sum, this resulted in a negative effect of woody plants on total plant C storage in the most arid grasslands in Xinjiang. As a consequence, we predict that woody plant encroachment may decrease rather than increase C storage in grasslands under future drier conditions.

Projections of water, carbon, and nitrogen dynamics under future climate change in an alpine tundra ecosystem in the southern Rocky Mountains using a biogeochemical model

Using statistically downscaled future climate scenarios and a version of the biogeochemical model (PnET-BGC) that was modified for use in the alpine tundra, we investigated changes in water, carbon, and nitrogen dynamics under the Representative Concentration Pathways at Niwot Ridge in Colorado, USA. Our simulations indicate that future hydrology will become more water-limited over the short-term due to the temperature-induced increases in leaf conductance, but remains energy-limited over the longer term because of anticipated future decreases in leaf area and increases in annual precipitation. The seasonal distribution of the water supply will become decoupled from energy inputs due to advanced snowmelt, causing soil moisture stress to plants during the growing season. Decreases in summer soil moisture are projected to not only affect leaf production, but also reduce decomposition of soil organic matter in summer despite increasing temperature. Advanced future snowmelt in spring and increasing rain to snow ratio in fall are projected to increase soil moisture and decomposition of soil organic matter. The extended growing season is projected to increase carbon sequestration by 2% under the high radiative forcing scenario, despite a 31% reduction in leaf display due to the soil moisture stress. Our analyses demonstrate that future nitrogen uptake by alpine plants is regulated by nitrogen supply from mineralization, but plant nitrogen demand may also affect plant uptake under the warmer scenario. PnET-BGC simulations also suggest that potential CO2 effects on alpine plants are projected to cause larger increases in plant carbon storage than leaf and root production.

Global patterns of insect herbivory in gap and understorey environments, and their implications for woody plant carbon storage

Insect herbivory is thought to favour carbon allocation to storage in juveniles of shade‐tolerant trees. This argument assumes that insect herbivory in the understorey is sufficiently intense as to select for storage; however, understoreys might be less attractive to insect herbivores than canopy gaps, because of low resource availability and – at temperate latitudes – low temperatures. Although empirical studies show that shade‐tolerant species in tropical forests do allocate more photosynthate to storage than their light‐demanding associates, the same pattern has not been consistently observed in temperate forests. Does this reflect a latitudinal trend in the relative activity of insect herbivory in gap versus understorey environments? To date there has been no global review of the effect of light environment on insect herbivory in forests. We postulated that if temperature is the primary factor limiting insect herbivory, the effect of gaps on rates of insect herbivory should be more evident in temperate than in tropical forests; due to low growing season temperatures in the oceanic temperate forests of the Southern Hemisphere, the effect of gaps on insect herbivory rates should in turn be stronger there than in the more continental temperate climates of the Northern Hemisphere. We examined global patterns of insect herbivory in gaps versus understories through meta‐analysis of 87 conspecific comparisons of leaf damage in contrasting light environments. Overall, insect herbivory in gaps was significantly higher than in the understorey; insect herbivory was 50% higher in gaps than in understoreys of tropical forests but did not differ significantly between gaps and understories in temperate forests of either hemisphere. Results are consistent with the idea that low resource availability – and not temperature – limits insect herbivore activity in forest understoreys, especially in the tropics, and suggest the selective influence of insect herbivory on late‐successional tree species may have been over‐estimated.

豫西丘陵坡地弃耕农田植被演替对土壤碳、氮库的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 豫西丘陵坡地弃耕农田植被演替对土壤碳、氮库的影响 DOI: 10.5846/stxb201709261739 作者: 作者单位: 河南科技大学,河南科技大学,河南科技大学,河南科技大学,河南科技大学 作者简介: 通讯作者: 中图分类号: 基金项目: NSFC-河南人才培养联合基金（U1304306）；中国科学院战略性先导科技专项（XDA05050402）；河南科技大学第六届研究生创新基金（CXJJ-2016-ZR12） Effects of vegetation succession on soil carbon and nitrogen storage in abandoned hilly farmlands of the Western Henan Region Author: Affiliation: Henan University of Science and Technology,,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:在豫西丘陵坡地弃耕农田中，设置一个时间梯度为1，3，8，15，25 a的弃耕演替系列，调查其群落数量特征、物种组成、植被与土壤的碳、氮储量，分析群落的自然次生演替过程，并探讨土壤碳库与氮库对植物群落演替的响应机制。结果表明，弃耕农田群落演替缓慢，阶段性不明显，大致可划分为一、二年生草本→多年生草本+灌木两个阶段。定植物种的多样性变化与附近的原生植被有关。在25 a的演替进程中，草本植物始终占据优势，旱生植物数量约是中生植物的4倍，C3植物数量逐渐增多；群落α多样性指数呈先增大后减小趋势，Margalef丰富度指数、Pielou均匀度指数与Shannon-Wiener综合多样性指数最大值分别为1.53、0.95、2.18，表明弃耕农田的自然演替促使群落结构更加复杂并趋向稳定。群落植物的碳、氮储量随着生物量的增加而增加，在25 a时分别达到313.14 g/m2和11.69 g/m2。土壤碳储量与氮储量的变化相反，在演替后期（25 a）土壤碳储量增加到960.98 g/m2，而氮储量则降低至27.08 g/m2，表明豫西弃耕农田土壤具有"固碳放氮"的生态现象。RDA分析表明，群落盖度、密度和生物量是影响土壤碳、氮储量的主要因子。从群落的生态功能变化分析，按照弃耕演替时间推进，土壤碳储量逐渐增大，有利于生态系统碳固定；而土壤氮库的缩减则不利于群落的稳定，建议增加群落中豆科植物的丰富度，从而促进土壤氮素固定，缓解氮素流失。 Abstract:Understanding the vegetation, soil status, and their relationship on abandoned farmland plays an important role in the determination of future land use. In this study, five hilly farmlands abandoned for different periods of time (1, 3, 8, 15, and 25 years) were selected as a series of successive abandonments in the Western henan region to investigate the quantitative characteristics and species composition of the plant community and the carbon and nitrogen storage in vegetation and the soil, to analyze the natural secondary succession process of the plant community, and to discuss how the soil carbon and nitrogen pool responded to the plant community succession. The main results indicated that:The abandoned farmland communities that possessed a slow succession progress and generally included two indistinct succession stages, from annual or biennial herbs to perennial herbs and shrubs. The plant species diversity was closely related to the surrounding native vegetation. Over 25 years, herbs in the community always had an advantage status, the number of xerophytes was more than four times that of mesophytes, and the quantity of C3 plants increased gradually. The α diversity index first increased and then decreased, and the maximum values of the Margalef, Pielou and Shannon-Wiener indices were 1.53, 0.95, and 2.18, respectively. These data could provide proof that the community structure became more complex and stable after a natural succession process of 25 years. Both plant carbon storage and nitrogen storage increased as the community biomass constantly accumulated, reaching values of 313.14 g/m2 and 11.69 g/m2, respectively, at the 25-year succession stage. The soil carbon storage trend opposed that of soil nitrogen storage. In the climax stage (25 a), the soil carbon storage increased to 960.98 g/m2, whereas the soil nitrogen storage was reduced to 27.08 g/m2. Therefore, the changes in the soil property of the abandoned farmlands in the Western henan region resulted in the ecological phenomenon of "carbon fixation and nitrogen release". Redundancy analysis (RDA) showed that the community coverage, density and biomass were the main factors affecting soil carbon and nitrogen storage. The analysis of the ecological function changes of these communities showed that soil carbon storage gradually increased as the time since abandonment increased, which was beneficial to the carbon fixation of the ecosystem. However, the reduction in soil nitrogen storage in abandoned farmlands did not, contribute to the stability of the ecosystem. Thus, an increase the richness of leguminous plants in the community was suggested to promote biological immobilization of soil total nitrogen and alleviate soil nitrogen loss. 参考文献 相似文献 引证文献

Plant community effects on CH4 fluxes, root surface area, and carbon storage in experimental wetlands

Wetland creation is a form of ecological engineering that often relies on establishing a plant community to increase ecosystem services. However, we still lack understanding about how species composition and diversity affect certain wetland ecosystem functions associated with these ecosystem services. Our objective was to investigate the link between plant community (diversity and composition) and plant carbon storage, root surface area and methane (CH4) emission. We hypothesized that more diverse mixtures would 1) store more carbon in above and belowground biomass and 2) emit less CH4 due to increased root surface area and aeration. Three plant groups that represented different growth forms (i.e., “functional groups”: ferns, reeds and tussocks) were planted in mesocosms to represent four levels of functional diversity and every combination of functional groups at each diversity level. Unplanted mesocosms served as the zero diversity treatment. At peak biomass in 2014 and 2015, we harvested aboveground biomass and took soil cores from each mesocosm at 0–10cm to determine the root biomass and surface area. Methane fluxes were measured in situ using a closed chamber system and a Picarro G2301 CRDS analyzer. Fluxes did not vary by functional group richness level or composition. Presence of the reed and tussock functional groups decreased fluxes; however, root surface area was not correlated with CH4 emission. Plant carbon storage was greater in all treatments containing tussocks (expect for the reed tussock mixture) compared with ferns grown alone. Functional group richness did not have a significant effect on plant carbon storage, however there was a positive trend. Root surface area increased 87% from the first to second year; however, there were no differences among functional group richness levels or mixtures. Our results indicate that planting reed and tussock functional groups in dense clumps during restoration could maintain a high level of carbon storage and relatively low CH4 emissions.

Individual size but not additional nitrogen regulates tree carbon sequestration in a subtropical forest

Recent studies have indicated that tree carbon accumulation in subtropical forests has been negatively affected by global change phenomena such as warming and drought. However, the long-term effect of nitrogen addition on plant carbon storage remains poorly understood in these regions. In this study, we conducted a 10-year field experiment examining the effect of experimental N addition on plant growth and carbon storage in a subtropical Chinese fir forest. The N levels were 0 (control), 60, 120, and 240 kg ha−1 yr−1, and the N effects on tree carbon were divided into stand and individual levels. The results indicated that tree carbon storage at the stand scale was not affected by long-term N addition in the subtropical forest. By contrast, significant impacts of different tree size classes on carbon sequestration were found under different N treatments, which indicated that the amount of plant carbon sequestration was significantly enhanced with tree size class. Our findings highlight the importance of community structure and growth characteristics in Chinese fir forests, in which individual size but not additional N regulates tree carbon sequestration in this subtropical forest.

福州市森林碳储量定量估算及其对土地利用变化的响应

PDF HTML阅读 XML下载 导出引用 引用提醒 福州市森林碳储量定量估算及其对土地利用变化的响应 DOI: 10.5846/stxb201502110337 作者: 作者单位: 复旦大学环境科学与工程系,复旦大学环境科学与工程系,复旦大学环境科学与工程系,复旦大学环境科学与工程系 作者简介: 通讯作者: 中图分类号: 基金项目: The quantitative estimation of forest carbon storage and its response to land use change in Fuzhou, China Author: Affiliation: Department of Environmental Science and Engineering,Fudan University,Department of Environmental Science and Engineering,Fudan University,Department of Environmental Science and Engineering,Fudan University,Department of Environmental Science and Engineering,Fudan University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:基于RS与GIS技术，以遥感影像数据、土地利用数据、森林资源二类调查数据为主要数据源，采用逐步回归法建立森林蓄积量定量估测模型。根据“蓄积量-生物量-碳储量”推算方法，对福州市森林植被碳储量和碳密度进行估算。建立福州市土地利用转移矩阵，分析2000-2010年土地利用变化影响下的福州市森林碳储量变化特征。结果表明：（1）根据不同的森林类型，即常绿阔叶林、常绿针叶林、针阔混交林分别建立的多元线性回归模型修正决定系数分别为0.599、0.679、0.694，通过模型适用性检验和精度验证。（2）2000年、2010年福州市森林植被碳储量总量分别为12.499Tg、12.642Tg，植被碳密度分别为18.694、18.708 t/hm2，森林植被碳储量增加了1.430×105 t。（3）福州市闽清县、永泰县、闽侯县的森林植被碳密度常年保持较高水平，并呈现出增长趋势；罗源县、长乐市、连江县森林植被碳密度较低，并呈现下降趋势。（4）2000-2010年，灌木和耕地是主要土地利用类型转出者，森林和建设用地是主要土地利用类型转入者。森林主要由灌木和耕地转化，主要向建设用地、耕地进行转化。由于土地利用变化，10年间福州市总碳储量减少了1.711×104 t，其中土壤碳储量减少2.230×103 t，植被碳储量减少1.489×104 t。 Abstract:In this study, remote sensing (RS) images, land-use data, and forest resource inventory data were used to build a quantitative estimation model of forest volume via the stepwise regression method. The carbon storage and carbon density of forest vegetation in Fuzhou from 2000 to 2010 were analyzed using the Biomass Expansion Factor (BEF) method to correlate forest volume with volume, biomass and carbon storage. A land use transition matrix was created, and used to study the variation of forest carbon storage in response to land use change in Fuzhou. The results showed that:(1) the results of quantitative estimation models of forest volume which were build according to different type of forest (Evergreen broad-leaved forest, Evergreen coniferous forest, Mixed broadleaf-conifer forest) turned out the effects with the adjusted R2 being 0.599, 0.679, 0.694 respectively. All quantitative estimation models of forest volume passed the applicability and accuracy test. The calculated total forest volume in Fuzhou was 2.097×107 m3 in 2000 and 2.594×107 m3 in 2010, revealing an increase in volume over the course of a decade. Of all the geographical subdivisions of Fuzhou, Yongtai County maintained the greatest forest volume throughout the decade, while Changle County contained the lowest forest volume. (2) Total carbon storage by forest vegetation in Fuzhou city was 12.499 Tg in 2000 and 12.642 Tg in 2010. Thus, in ten years, forest vegetation carbon storage increased by 1.430×105 t. The vegetation carbon densities in 2000 and 2010 were 18.694 t/hm2 and 18.708 t/hm2, respectively. (3) The carbon density of forest vegetation in Minqing County, Yongtai County, and Minhou County, which are located in western Fuzhou, remained high during this ten year period, and was observed to increase overall. In contrast, Luoyuan County, Changle County, and Lianjiang County, which are located in eastern Fuzhou, experienced declines in the carbon density of forest vegetation, as a result of increasing socio-economic and anthropogenic activity. (4) In these areas, the forest was mostly converted to shrub and crop land between 2000 and 2010. As a result of this change in land use, forest carbon storage in Fuzhou declined by 1.711×104 t overall. In addition, soil carbon storage and plant carbon storage decreased by 2.230×103 t and 1.489×104 t, respectively. 参考文献 相似文献 引证文献

Mutualism-disrupting allelopathic invader drives carbon stress and vital rate decline in a forest perennial herb.

Invasive plants can negatively affect belowground processes and alter soil microbial communities. For native plants that depend on soil resources from root fungal symbionts (RFS), invasion could compromise their resource status and subsequent ability to manufacture and store carbohydrates. Herbaceous perennials that depend on RFS-derived resources dominate eastern North American forest understories. Therefore, we predict that forest invasion by Alliaria petiolata, an allelopathic species that produces chemicals that are toxic to RFS, will diminish plant carbon storage and fitness. Over a single growing season, the loss of RFS could reduce a plant's photosynthetic physiology and carbon storage. If maintained over multiple growing seasons, this could create a condition of carbon stress and declines in plant vital rates. Here we characterize the signals of carbon stress over a short timeframe and explore the long-term consequence of Alliaria invasion using Maianthemum racemosum, an RFS-dependent forest understory perennial. First, in a greenhouse experiment, we treated the soil of potted Maianthemum with fresh leaf tissue from either Alliaria or Hesperis matronalis (control) for a single growing season. Alliaria-treated plants exhibit significant overall reductions in total non-structural carbohydrates and have 17 % less storage carbohydrates relative to controls. Second, we monitored Maianthemum vital rates in paired experimental plots where we either removed emerging Alliaria seedlings each spring or left Alliaria at ambient levels for 7 years. Where Alliaria is removed, Maianthemum size and vital rates improve significantly: flowering probability increases, while the probability of plants regressing to non-flowering stages or entering prolonged dormancy are reduced. Together, our results are consistent with the hypothesis that disruption of a ubiquitous mutualism following species invasion creates symptoms of carbon stress for species dependent on RFS. Disruption of plant-fungal mutualisms may generally contribute to the common, large-scale declines in forest biodiversity observed in the wake of allelopathic invaders.

The Invasion of Spartina alterniflora Alters Carbon Dynamics in China&amp;apos;s Yancheng Natural Reserve

Ecosystem processes are tightly linked to the structure and functioning of plant communities. Large‐scale invasion of Spartina alterniflora on unvegetated intertidal mudflats is expected to reduce atmospheric CO2 through an increase in the carbon storage of coastal ecosystem. In China&amp;apos;s Yancheng Natural Reserve, plant carbon storage (PCS), soil total organic carbon storage (SCS), as well as CO2 and CH4 fluxes, were compared between Spartina invaded marsh and adjacent native marshes. PCS of Spartina marsh was 16.9 and 1.4 times higher compared to those of Suaeda and Phragmites marshes, whereas relatively larger aboveground PCS but smaller belowground PCS were found in the newly settled seaward margin of the Spartina marsh. SCS in Spartina marsh was also 1.5 times higher than that in unvegetated mudflat. Although Spartina vegetation assimilated a substantial amount of CO2, mass emission of CH4 from the invaded marsh was also noticed, especially in summer, it was 9–16 times higher than those from native marshes. Our study indicates that instead of CO2 being simply incorporated into PCS and SCS, carbon dynamics following Spartina invasion are more complicated. Detailed studies of CH4 emissions are needed before ascertaining whether, and to what degree, the invasion of S. alterniflora may affect the global warming process.

Soil warming, carbon–nitrogen interactions, and forest carbon budgets

Soil warming has the potential to alter both soil and plant processes that affect carbon storage in forest ecosystems. We have quantified these effects in a large, long-term (7-y) soil-warming study in a deciduous forest in New England. Soil warming has resulted in carbon losses from the soil and stimulated carbon gains in the woody tissue of trees. The warming-enhanced decay of soil organic matter also released enough additional inorganic nitrogen into the soil solution to support the observed increases in plant carbon storage. Although soil warming has resulted in a cumulative net loss of carbon from a New England forest relative to a control area over the 7-y study, the annual net losses generally decreased over time as plant carbon storage increased. In the seventh year, warming-induced soil carbon losses were almost totally compensated for by plant carbon gains in response to warming. We attribute the plant gains primarily to warming-induced increases in nitrogen availability. This study underscores the importance of incorporating carbon-nitrogen interactions in atmosphere-ocean-land earth system models to accurately simulate land feedbacks to the climate system.