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Enrong Yan - One of the best experts on this subject based on the ideXlab platform.
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rhizosphere effects on soil microbial community structure and enzyme activity in a Successional subtropical Forest
FEMS Microbiology Ecology, 2019Co-Authors: Tiantian Zheng, Enrong Yan, Chao Liang, Hongtu Xie, Jinsong Zhao, Xuhui Zhou, Xuelian BaoAbstract:Forest Succession is a central ecological topic due to the importance of its dynamic process for terrestrial ecosystems. However, we have limited knowledge of the relationship between Forest Succession and belowground microbiota, particularly regarding interactions in the rhizosphere. Here, we determined microbial community structure and biomass using phospholipid fatty acid (PLFA) biomarkers and microbial activity using extracellular enzyme activity in bulk and rhizosphere soils from three Successional stages of subtropical Forests in eastern China. Principal component analysis of PLFAs indicated distinct soil microbial communities among different Successional stages and habitat locations. Specifically for the topsoil, we found the total microbial biomass, bacterial biomass and enzyme activities showed higher levels in the late than early stage, with a significant Succession-induced accentuated rhizosphere effect. The increase in total microbial biomass and activity coincided with a net growth in bacterial rather than fungal biomass, indicating a model in which microbial biomass carrying capacity and activity could be affected by the creation or expansion of niches for certain functional group rather than by a rebalancing of competitive interactions among these groups. Furthermore, we demonstrated that Forest Succession significantly influenced enzyme activity via the changes in microbial biomass, as driven by edaphic factors. Overall, our study deepens the mechanistic understanding of Forest recovery by linking soil microbial community and activity along Successional chronosequences.
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long lasting legacy of Forest Succession and Forest management characteristics of coarse woody debris in an evergreen broad leaved Forest of eastern china
Forest Ecology and Management, 2007Co-Authors: Enrong Yan, Xihua Wang, Jianjun Huang, Fanrong Zeng, Long GongAbstract:Coarse woody debris (CWD) is an important structural and functional component in evergreen broad-leaved Forests in Eastern China. In this study, we determine the temporal patterns of CWD in Tiantong National Forest Park by examining the CWD volume and mass in different decay classes and size classes along a chronosequence of secondary Forest Succession. The volume and mass of CWD followed the general ‘‘U-shaped’’ temporal trend: highest in the late-Successional Forest (97.73 m 3 /ha, 42.41 Mg/ha), lowest in the middle Successional Forest (6.13 m 3 /ha, 2.84 Mg/ ha) and intermediate in the early Successional Forest (46.12 m 3 /ha, 19.36 Mg/ha). The late-Successional Forest had larger amount of logs and stumps than the other two Forests. In contrast, snags biomass and volume did not differ among these three Forests. CWD in decay classes III and V was greater in late-Successional Forest than that in the other two Forests, while CWD in decay classes II and IV did not differ among the three Successional Forests. CWD in class I was significantly higher in the early-Successional Forest than that in the middle Successional Forest. In the early and middle Successional Forests, CWD in early decay class was dominated by Pinus massoniana and followed by Schima superba. In the lateSuccessional Forest, CWD in early decay class was dominated by Castanopsis fargesii while CWD in late decay class was dominated by P. massoniana and S. superba. While Forest Succession had a large influence on the amount of CWD in different decay class, it had no effect on CWD distribution among different size classes. Our results suggested that both anthropogenic and natural disturbances have left a long-lasting legacy on the distribution of CWD among three Forests. # 2007 Elsevier B.V. All rights reserved.
Michiel Van Breugel - One of the best experts on this subject based on the ideXlab platform.
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liana effects on biomass dynamics strengthen during secondary Forest Succession
Ecology, 2017Co-Authors: Jefferson S Hall, Benjamin L Turner, Michiel Van BreugelAbstract:: Secondary Forests are important carbon sinks, but their biomass dynamics vary markedly within and across landscapes. The biotic and abiotic drivers of this variation are still not well understood. We tested the effects of soil resource availability and competition by lianas on the biomass dynamics of young secondary tropical Forests in Panama and assessed the extent to which liana effects were mediated by soil resource availability. Over a five-year period, growth, mortality, and recruitment of woody plants of ≥1 cm diameter were monitored in 84 plots in 3-30-year-old secondary Forests across the Agua Salud site in central Panama. Biomass dynamics and the effects of lianas and soil resources were examined using (generalized) linear mixed-effect models and a model averaging approach. There was strong spatial and temporal variation in liana biomass within and across the plots. The relative biomass of lianas had a strong negative effect on overall tree growth, growth of understory trees decreased with soil fertility and dry season soil water content, and the effect of lianas on tree mortality varied with soil fertility. Tree recruitment was not associated with any of the predictor variables. Our model indicates that tree biomass growth across our landscape was reduced with 22% due to competition with lianas, and that the effect of lianas increased during Succession, from 19% after five years to 32% after 30 years. The projected liana-induced growth reduction after 60 years was 47%, which was consistent with data from a nearby site. Our study shows that the observed liana proliferation across tropical Forests may reduce the sequestration and storage of carbon in young secondary Forests, with important implications for the carbon balance of tropical Forest landscapes and consequently for global climate change. Our study highlights the need to incorporate lianas and soil variables in research on the biomass dynamics of secondary Forest across tropical landscapes, and the need for well-replicated longitudinal studies to cover landscape-level variability in the relevant abiotic and biotic components.
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species dynamics during early secondary Forest Succession recruitment mortality and species turnover
Biotropica, 2007Co-Authors: Michiel Van Breugel, Frans Bongers, Miguel MartinezramosAbstract:The “Initial Floristic Composition” hypothesis is applied to secondary tropical rain Forest Succession in abandoned agricultural fields with light previous land-use and close to seed sources. This hypothesis predicts that both pioneer and shade-tolerant species colonize a site directly after abandonment, and as the canopy closes, the recruitment of pioneers sharply declines, while recruitment of shade-tolerant species continues. It also predicts higher mortality among pioneers. Consequently, recruited and dead trees are expected to differ in species composition, with highest species richness for the recruits. During 18 mo, we monitored recruitment and mortality of trees with height ≥ 1.5 m in eight plots in abandoned cornfields with initial fallow age of 1–5 yr, in SE Mexico. Shade-tolerant species established in the first years of Succession, albeit in low numbers. As predicted, recruited and dead trees differed in species richness and composition, and in shade-tolerant frequency. In contrast to our expectations, over 50 percent of recruits were from pioneer species, as high stand-level mortality opened new opportunities for continued pioneer colonization. Species turnover starts very early in Succession but is not always a gradual and continuous process, complicating prevailing Succession models. The strong spatial and temporal variability of Succession emphasizes the need to monitor these dynamics in permanent plots across a range of initial stand ages, with multiple plots in a given age class.
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community dynamics during early secondary Succession in mexican tropical rain Forests
Journal of Tropical Ecology, 2006Co-Authors: Michiel Van Breugel, Frans BongersAbstract:Stand structure dynamics during early secondary Forest Succession were related to mortality, growth and recruitment rates, and the dependence of these demographic processes on fallow age and initial stand structure attributes was evaluated. In 11 secondary tropical rain-Forest sites (1.5-19 y) in Chiapas, Mexico, one plot of 10 × 50 m was established. Diameter and height were measured for all trees ≥ 1 cm dbh, and their survival, growth and recruitment was monitored over a 2-y period. Changes in stand structure were especially fast in the first 5 y of Succession, and decreased rapidly afterwards, which resulted from similar stand-level changes in relative mortality, growth and recruitment rates. Demographic processes were negatively related with initial stand basal area, but independent of initial tree density. Basal area was a better explanatory variable of the among-stand variability in these rates than fallow age. Results suggest that asymmetric competition and resulting patterns of tree-thinning are major driving forces determining secondary Forest Successional pathways. Fallow age per se is a compound variable reflecting community organization at a certain point along the Successional axis, while community structure drives Succession. Sudden mass mortality among dominant species in some stands showed that early secondary Forest Succession is not always a gradual and unidirectional process.
Achilleas Psomas - One of the best experts on this subject based on the ideXlab platform.
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mapping secondary Forest Succession on abandoned agricultural land with lidar point clouds and terrestrial photography
Remote Sensing, 2015Co-Authors: Natalia Kolecka, Jacek Kozak, Dominik Kaim, Monika Dobosz, Christian Ginzler, Achilleas PsomasAbstract:Secondary Forest Succession on abandoned agricultural land has played a significant role in land cover changes in Europe over the past several decades. However, it is difficult to quantify over large areas. In this paper, we present a conceptual framework for mapping Forest Succession patterns using vegetation structure information derived from LiDAR data supported by national topographic vector data. This work was performed in the Szczawnica commune in the Polish Carpathians. Using object-based image analysis segments of no vegetation, and sparse/dense low/medium/high vegetation were distinguished and subsequently compared to the national topographic dataset to delineate agricultural land that is covered by vegetation, which indicates secondary Succession on abandoned fields. The results showed that 18.7% of the arable land and 40.4% of grasslands, that is 31.0% of the agricultural land in the Szczawnica commune, may currently be experiencing secondary Forest Succession. The overall accuracy of the approach was assessed using georeferenced terrestrial photographs and was found to be 95.0%. The results of this study indicate that the proposed methodology can potentially be applied in large-scale mapping of secondary Forest Succession patterns on abandoned land in mountain areas.
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mapping secondary Forest Succession on abandoned agricultural land with lidar point clouds and terrestrial photography
Remote Sensing, 2015Co-Authors: Natalia Kolecka, Jacek Kozak, Dominik Kaim, Monika Dobosz, Christian Ginzler, Achilleas PsomasAbstract:Secondary Forest Succession on abandoned agricultural land has played a significant role in land cover changes in Europe over the past several decades. However, it is difficult to quantify over large areas. In this paper, we present a conceptual framework for mapping Forest Succession patterns using vegetation structure information derived from LiDAR data supported by national topographic vector data. This work was performed in the Szczawnica commune in the Polish Carpathians. Using object-based image analysis segments of no vegetation, and sparse/dense low/medium/high vegetation were distinguished and subsequently compared to the national topographic dataset to delineate agricultural land that is covered by vegetation, which indicates secondary Succession on abandoned fields. The results showed that 18.7% of the arable land and 40.4% of grasslands, that is 31.0% of the agricultural land in the Szczawnica commune, may currently be experiencing secondary Forest Succession. The overall accuracy of the approach was assessed using georeferenced terrestrial photographs and was found to be 95.0%. The results of this study indicate that the proposed methodology can potentially be applied in large-scale mapping of secondary Forest Succession patterns on abandoned land in mountain areas.
Hai Ren - One of the best experts on this subject based on the ideXlab platform.
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dynamics of community structure and bio thermodynamic health of soil organisms following subtropical Forest Succession
Journal of Environmental Management, 2021Co-Authors: Jun Wang, Yongbiao Lin, Daniel E Campbell, Hongyue Cai, Hai RenAbstract:Abstract Soil organisms play essential roles in maintaining multiple ecosystem processes, but our understanding of the dynamics of these communities during Forest Succession remains limited. In this study, the dynamics of soil organism communities were measured along a 3-step Succession sequence of subtropical Forests (i.e., a conifer Forest, CF; a mixed conifer and broad-leaved Forest, MF; and a monsoon evergreen broad-leaved Forest, BF). The eco-exergy evaluation method was used as a complement to the classic community structure index system to reveal the holistic dynamics of the bio-thermodynamic health of soil organism communities in a Forest Succession series. Association between the self-organization of soil organisms, soil properties, and plant factors were explored through redundancy analyses (RDA). The results indicated that the biomass of soil microbes progressively increased in the dry season, from 0.75 g m−2 in CF to 1.75 g m−2 in BF. Microbial eco-exergy showed a similar pattern, while the community structure and the specific eco-exergy remained constant. Different trends for the seasons were observed for the soil fauna community, where the community biomass increased from 0.72 g m−2 to over 1.97 g m−2 in the dry season, but decreased from 3.94 g m−2 to 2.36 g m−2 in the wet season. Faunal eco-exergies followed a similar pattern. Consequently, the average annual biomass of the soil faunal community remained constant (2.17–2.39 g m−2) along the Forest Succession sequence, while the significant seasonal differences in both faunal biomass and eco-exergy observed at the early Successional stage (CF) were insignificant in the middle and late Forest Successional stages (MF and BF). Both the dynamics of soil microbes and soil fauna were tightly correlated with tree biomass and with soil physicochemical properties, especially soil pH, moisture, total nitrogen, nitrate nitrogen, and organic matter content.
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quantifying ecological memory during Forest Succession a case study from lower subtropical Forest ecosystems in south china
Ecological Indicators, 2013Co-Authors: Zhongyu Sun, Jun Wang, Hai Ren, Valentin Schaefer, Nan LiuAbstract:Abstract The concept of ecological memory provides a new perspective for research on Forest Succession by including historical factors and the initial state of ecological processes. However, there are still significant gaps between the concept and its application. We selected nine proxy indicators (plant species, soil seed banks, soil microbes, soil animals, birds, soil age, soil pollen, soil mineral distribution, and light environment) and developed a method to quantify ecological memory and Succession in a subtropical Forest Succession in South China. Taking the climax-monsoon evergreen broad-leaved Forest as the reference ecosystem, we found that ecological memory increased nonlinearly and accumulated following a specific assembly rule during Succession. Memory concerning major soil microbes and soil animals, which improve the soil substrate, mainly accumulated from the initial to the early Successional stage. Memory concerning the number of bird species and the availability of light, which ensure a source of regenerative seeds and the survival of understory seedlings, mainly accumulated from the early to middle Successional stages. Memory concerning vegetation and soil seed banks mainly accumulated late in Succession, guaranteeing that the ecosystem would reach the regional climax stage. Prospective memory was greater than retrospective memory in every Successional stage except the late stage, which indicated that all stages but the late stage were undergoing progressive Succession. Our study demonstrates that the concept of ecological memory and the proposed evaluation framework are useful for guiding research on Succession and restoration, and especially for assessing how “far” a restored ecosystem is from a reference ecosystem or how far a restored ecosystem has deviated from its natural Succession trajectory.
Jun Wang - One of the best experts on this subject based on the ideXlab platform.
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dynamics of community structure and bio thermodynamic health of soil organisms following subtropical Forest Succession
Journal of Environmental Management, 2021Co-Authors: Jun Wang, Yongbiao Lin, Daniel E Campbell, Hongyue Cai, Hai RenAbstract:Abstract Soil organisms play essential roles in maintaining multiple ecosystem processes, but our understanding of the dynamics of these communities during Forest Succession remains limited. In this study, the dynamics of soil organism communities were measured along a 3-step Succession sequence of subtropical Forests (i.e., a conifer Forest, CF; a mixed conifer and broad-leaved Forest, MF; and a monsoon evergreen broad-leaved Forest, BF). The eco-exergy evaluation method was used as a complement to the classic community structure index system to reveal the holistic dynamics of the bio-thermodynamic health of soil organism communities in a Forest Succession series. Association between the self-organization of soil organisms, soil properties, and plant factors were explored through redundancy analyses (RDA). The results indicated that the biomass of soil microbes progressively increased in the dry season, from 0.75 g m−2 in CF to 1.75 g m−2 in BF. Microbial eco-exergy showed a similar pattern, while the community structure and the specific eco-exergy remained constant. Different trends for the seasons were observed for the soil fauna community, where the community biomass increased from 0.72 g m−2 to over 1.97 g m−2 in the dry season, but decreased from 3.94 g m−2 to 2.36 g m−2 in the wet season. Faunal eco-exergies followed a similar pattern. Consequently, the average annual biomass of the soil faunal community remained constant (2.17–2.39 g m−2) along the Forest Succession sequence, while the significant seasonal differences in both faunal biomass and eco-exergy observed at the early Successional stage (CF) were insignificant in the middle and late Forest Successional stages (MF and BF). Both the dynamics of soil microbes and soil fauna were tightly correlated with tree biomass and with soil physicochemical properties, especially soil pH, moisture, total nitrogen, nitrate nitrogen, and organic matter content.
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variations of leaf eco physiological traits in relation to environmental factors during Forest Succession
Ecological Indicators, 2020Co-Authors: Jun Wang, Hongfang Lu, Guangman Song, Robin L ChazdonAbstract:Abstract Changes in leaf physiological trait indicators and shifts in their relationships are expected to reveal plant ecological strategies during Succession, and how they interact with the changing environment are thought to be useful in Forest restoration and management. In this study, 9 physiological trait indicators, 7 leaf structural and chemical trait indicators of each dominant species across a Successional series were measured in southern China; 14 environmental factors were also measured to identify which factors were most associated with leaf physiological trait indicators. Results showed that leaf photosynthesis (Amass and Aarea), respiration, transpiration (Tmass and Tarea), photosynthetic N-, and P-use efficiency (PNUE and PPUE) decreased during Succession, which could be explained by plant life forms. Species at a given Amass had higher PPUE and specific leaf area (SLA) in later- than in early-Succession. At a given SLA, leaf N content was higher in early- than in later-Succession. Changes in leaf physiological trait indicators were associated with soil pH. The higher N, P assimilation efficiencies of pioneer species support their rapid growth in the relatively low N, P soils in early stage of Succession. Leaf nutrient-utilization strategies, interacting with soil pH, played an important role in the Succession of subtropical Forest. Soil pH could be used as an indicator of the process of Forest dynamic Succession in south China. This study can also advance the understanding of plant survival and replacement strategies during Forest Succession.
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quantifying ecological memory during Forest Succession a case study from lower subtropical Forest ecosystems in south china
Ecological Indicators, 2013Co-Authors: Zhongyu Sun, Jun Wang, Hai Ren, Valentin Schaefer, Nan LiuAbstract:Abstract The concept of ecological memory provides a new perspective for research on Forest Succession by including historical factors and the initial state of ecological processes. However, there are still significant gaps between the concept and its application. We selected nine proxy indicators (plant species, soil seed banks, soil microbes, soil animals, birds, soil age, soil pollen, soil mineral distribution, and light environment) and developed a method to quantify ecological memory and Succession in a subtropical Forest Succession in South China. Taking the climax-monsoon evergreen broad-leaved Forest as the reference ecosystem, we found that ecological memory increased nonlinearly and accumulated following a specific assembly rule during Succession. Memory concerning major soil microbes and soil animals, which improve the soil substrate, mainly accumulated from the initial to the early Successional stage. Memory concerning the number of bird species and the availability of light, which ensure a source of regenerative seeds and the survival of understory seedlings, mainly accumulated from the early to middle Successional stages. Memory concerning vegetation and soil seed banks mainly accumulated late in Succession, guaranteeing that the ecosystem would reach the regional climax stage. Prospective memory was greater than retrospective memory in every Successional stage except the late stage, which indicated that all stages but the late stage were undergoing progressive Succession. Our study demonstrates that the concept of ecological memory and the proposed evaluation framework are useful for guiding research on Succession and restoration, and especially for assessing how “far” a restored ecosystem is from a reference ecosystem or how far a restored ecosystem has deviated from its natural Succession trajectory.