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Jian Sun - One of the best experts on this subject based on the ideXlab platform.
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Grazing enhances soil nutrient effects: Trade-offs between aboveground and Belowground Biomass in alpine grasslands of the Tibetan Plateau
Land Degradation & Development, 2017Co-Authors: Jian SunAbstract:Understanding the impact of grazing patterns on grassland production is of fundamental importance for grassland conservation and management. The objective of this study is to obtain an understanding of the trade-offs between aboveground Biomass and Belowground Biomass, which are influenced by environmental factors in free grazing (FG) and grazing exclusion (GE) alpine grasslands on the Tibetan Plateau. We explored the relationships between the trade-off and environmental factors using correlation analysis, a generalized additive model and a structural equation model, and then found that the key factors that determine trade-off showed differences in FG and GE grasslands and that the final structural equation modeling result explained that 96% (path coefficient=0.96) and 65% (path coefficient=0.65) of the variations in the trade-off were due to FG or GE classifications, respectively. The results demonstrated that soil organic carbon, soil carbon/soil nitrogen, and soil available nitrogen affect the trade-off between aboveground and Belowground Biomass in FG grasslands more obviously than in GE grasslands. However, the effects of growing season temperature on the trade-off were insignificant, -0.218 and -0.181 in FG and GE grasslands, respectively. FG increased the soil bulk density, which resulted in an alteration in the soil pore size distribution and a greater resistance to root penetration. In addition, FG affected the level of soil nutrition, which will affect the nitrogen mineralization of decomposition and absorption, as well as the root Biomass. Consequently, this study can provide guidance to improve the quality of grassland.
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effects of soil nutrients and climate factors on Belowground Biomass in an alpine meadow in the source region of the yangtze yellow rivers tibetan plateau of china
Journal of Arid Land, 2016Co-Authors: Haiming Wang, Jian Sun, Youjun Chen, Wenhui LiuAbstract:Improving our knowledge of the effects of environmental factors (e.g. soil conditions, precipitation and temperature) on Belowground Biomass in an alpine grassland is essential for understanding the consequences of carbon storage in this biome. The object of this study is to investigate the relative importance of soil nutrients and climate factors on Belowground Biomass in an alpine meadow in the source region of the Yangtze and Yellow rivers, Tibetan Plateau. Soil organic carbon (SOC), total nitrogen (TN) and total phosphorous (TP) contents and Belowground Biomass were measured at 22 sampling sites across an alpine meadow on the Tibetan Plateau. We analyzed the data by using the redundancy analysis to determine the main environmental factors affecting the Belowground Biomass and the contribution of each factor. The results showed that SOC, TN and TP were the main factors that influenced Belowground Biomass, and the contribution of SOC, TN and TP on Biomass was in the range of 47.87%–72.06% at soil depths of 0–30 cm. Moreover, the combined contribution of annual mean temperature (AMT) and mean annual precipitation (MAP) on Belowground Biomass ranged from 0.92% to 4.10%. A potential mechanism for the differences in Belowground Biomass was caused by the variations in soil nitrogen and phosphorous, which were coupled with SOC. A significant correlation was observed between MAP and soil nutrients (SOC, TN and TP) at the soil depth of 0–10 cm (P<0.05). We concluded that precipitation is an important driving force in regulating ecosystem functioning as reflected in variations of soil nutrients (SOC, TN and TP) and dynamics of Belowground Biomass in alpine grassland ecosystems.
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Effects of soil nutrients and climate factors on Belowground Biomass in an alpine meadow in the source region of the Yangtze-Yellow rivers, Tibetan Plateau of China
Journal of Arid Land, 2016Co-Authors: Haiming Wang, Jian Sun, Youjun Chen, Wenhui LiuAbstract:Improving our knowledge of the effects of environmental factors (e.g. soil conditions, precipitation and temperature) on Belowground Biomass in an alpine grassland is essential for understanding the consequences of carbon storage in this biome. The object of this study is to investigate the relative importance of soil nutrients and climate factors on Belowground Biomass in an alpine meadow in the source region of the Yangtze and Yellow rivers, Tibetan Plateau. Soil organic carbon (SOC), total nitrogen (TN) and total phosphorous (TP) contents and Belowground Biomass were measured at 22 sampling sites across an alpine meadow on the Tibetan Plateau. We analyzed the data by using the redundancy analysis to determine the main environmental factors affecting the Belowground Biomass and the contribution of each factor. The results showed that SOC, TN and TP were the main factors that influenced Belowground Biomass, and the contribution of SOC, TN and TP on Biomass was in the range of 47.87%–72.06% at soil depths of 0–30 cm. Moreover, the combined contribution of annual mean temperature (AMT) and mean annual precipitation (MAP) on Belowground Biomass ranged from 0.92% to 4.10%. A potential mechanism for the differences in Belowground Biomass was caused by the variations in soil nitrogen and phosphorous, which were coupled with SOC. A significant correlation was observed between MAP and soil nutrients (SOC, TN and TP) at the soil depth of 0–10 cm (P
Yojiro Matsuura - One of the best experts on this subject based on the ideXlab platform.
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high Belowground Biomass allocation in an upland black spruce picea mariana stand in interior alaska
Polar Science, 2012Co-Authors: Kyotaro Noguchi, Masako Dannoura, Mayuko Jomura, Motoko Awazuharanoguchi, Yojiro MatsuuraAbstract:The root system of forest trees account for a significant proportion of the total forest Biomass. However, data is particularly limited for forests in permafrost regions. In this study, therefore, we estimated the above- and Belowground Biomass of a black spruce (Picea mariana) stand underlain with permafrost in interior Alaska. Allometric equations were established using 4–6 sample trees to estimate the Biomass of the aboveground parts and the coarse roots (roots >5 mm in diameter) of P. mariana trees. The aboveground Biomass of understory plants and the fine-root Biomass were estimated by destructive sampling. The aboveground and coarse-root Biomasses of the P. mariana trees were estimated to be 3.97 and 2.31 kg m−2, respectively. The aboveground Biomass of understory vascular plants such as Ledum groenlandicum and the Biomass of forest floor mosses and lichens were 0.10 and 0.62 kg m−2, respectively. The Biomass of fine roots <5 mm in diameter was 1.27 kg m−2. Thus, the above- and Belowground Biomasses of vascular plants in the P. mariana stand were estimated to be 4.07 and 3.58 kg m−2, respectively, indicating that Belowground Biomass accounted for 47% of the total Biomass of vascular plants. Fine-root Biomass was 36% of the total root Biomass, of which 90% was accumulated in the surface organic layer. Thus, this P. mariana stand can be characterized as having extremely high Belowground Biomass allocation, which would make it possible to grow on permafrost with limited soil resource availability.
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High Belowground Biomass allocation in an upland black spruce (Picea mariana) stand in interior Alaska
Polar Science, 2012Co-Authors: Kyotaro Noguchi, Masako Dannoura, Mayuko Jomura, Motoko Awazuhara-noguchi, Yojiro MatsuuraAbstract:The root system of forest trees account for a significant proportion of the total forest Biomass. However, data is particularly limited for forests in permafrost regions. In this study, therefore, we estimated the above- and Belowground Biomass of a black spruce (Picea mariana) stand underlain with permafrost in interior Alaska. Allometric equations were established using 4–6 sample trees to estimate the Biomass of the aboveground parts and the coarse roots (roots >5 mm in diameter) of P. mariana trees. The aboveground Biomass of understory plants and the fine-root Biomass were estimated by destructive sampling. The aboveground and coarse-root Biomasses of the P. mariana trees were estimated to be 3.97 and 2.31 kg m−2, respectively. The aboveground Biomass of understory vascular plants such as Ledum groenlandicum and the Biomass of forest floor mosses and lichens were 0.10 and 0.62 kg m−2, respectively. The Biomass of fine roots
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above and Belowground Biomass and net primary productivity of a larix gmelinii stand near tura central siberia
Tree Physiology, 1999Co-Authors: Takuya Kajimoto, Yojiro Matsuura, Mark A Sofronov, A V Volokitina, Shigeta Mori, Akira Osawa, A P AbaimovAbstract:We assessed above- and Belowground Biomass and net primary production (NPP) of a mature Larix gmelinii (Rupr.) Rupr. forest (240-280 years old) established on permafrost soils in central Siberia. Specifically, we investigated annual carbon budgets in roots in relation to root system development and availability of soil resources. Total stand Biomass estimated by allometry was about 39 Mg ha −1 . Root Biomass (17 Mg ha −1 ) comprised about 43% of total Biomass. Coarse root (≥ 5 mm in diameter) Biomass was about twice that of fine roots (< 5 mm). The aboveground Biomass/root Biomass ratio (T/R) of the larch stand was about unity, which is much less than that of other boreal and subalpine conifer forests. The proportion of fine roots in total root Biomass (35%) was relatively high compared with other cold-climate evergreen conifer forests. Total NPP, defined as the sum of annual Biomass increment of woody parts and needle Biomass, was estimated to be 1.8 Mg ha −1 year −1 . Allocation of total NPP to needle production was 56%. The proportion of total NPP in Belowground production (27%) was less than for evergreen taiga forests. However, Belowground NPP was probably underestimated because root mortality was excluded. We conclude that L. gmelinii trees invested annual carbon gains largely into needle production or roots, or both, at the expense of growth of aboveground woody parts. This carbon allocation pattern, which resulted in the construction of exploitative root networks, appeared to be a positive growth response to the nutrient-poor permafrost soil of central Siberia.
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Above- and Belowground Biomass and net primary productivity of a Larix gmelinii stand near Tura, central Siberia
Tree physiology, 1999Co-Authors: Takuya Kajimoto, Yojiro Matsuura, Mark A Sofronov, A V Volokitina, Shigeta Mori, Akira Osawa, A P AbaimovAbstract:We assessed above- and Belowground Biomass and net primary production (NPP) of a mature Larix gmelinii (Rupr.) Rupr. forest (240-280 years old) established on permafrost soils in central Siberia. Specifically, we investigated annual carbon budgets in roots in relation to root system development and availability of soil resources. Total stand Biomass estimated by allometry was about 39 Mg per ha. Root Biomass (17 Mg per ha) comprised about 43% of total Biomass. Coarse root (>/= 5 mm in diameter) Biomass was about twice that of fine roots (< 5 mm). The aboveground Biomass/root Biomass ratio (T/R) of the larch stand was about unity, which is much less than that of other boreal and subalpine conifer forests. The proportion of fine roots in total root Biomass (35%) was relatively high compared with other cold-climate evergreen conifer forests. Total NPP, defined as the sum of annual Biomass increment of woody parts and needle Biomass, was estimated to be 1.8 Mg per ha per year. Allocation of total NPP to needle production was 56%. The proportion of total NPP in Belowground production (27%) was less than for evergreen taiga forests. However, Belowground NPP was probably under-estimated because root mortality was excluded. We conclude that L. gmelinii trees invested annual carbon gains largely into needle production or roots, or both, at the expense of growth of aboveground woody parts. This carbon allocation pattern, which resulted in the construction of exploitative root networks, appeared to be a positive growth response to the nutrient-poor permafrost soil of central Siberia.
A P Abaimov - One of the best experts on this subject based on the ideXlab platform.
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above and Belowground Biomass and net primary productivity of a larix gmelinii stand near tura central siberia
Tree Physiology, 1999Co-Authors: Takuya Kajimoto, Yojiro Matsuura, Mark A Sofronov, A V Volokitina, Shigeta Mori, Akira Osawa, A P AbaimovAbstract:We assessed above- and Belowground Biomass and net primary production (NPP) of a mature Larix gmelinii (Rupr.) Rupr. forest (240-280 years old) established on permafrost soils in central Siberia. Specifically, we investigated annual carbon budgets in roots in relation to root system development and availability of soil resources. Total stand Biomass estimated by allometry was about 39 Mg ha −1 . Root Biomass (17 Mg ha −1 ) comprised about 43% of total Biomass. Coarse root (≥ 5 mm in diameter) Biomass was about twice that of fine roots (< 5 mm). The aboveground Biomass/root Biomass ratio (T/R) of the larch stand was about unity, which is much less than that of other boreal and subalpine conifer forests. The proportion of fine roots in total root Biomass (35%) was relatively high compared with other cold-climate evergreen conifer forests. Total NPP, defined as the sum of annual Biomass increment of woody parts and needle Biomass, was estimated to be 1.8 Mg ha −1 year −1 . Allocation of total NPP to needle production was 56%. The proportion of total NPP in Belowground production (27%) was less than for evergreen taiga forests. However, Belowground NPP was probably underestimated because root mortality was excluded. We conclude that L. gmelinii trees invested annual carbon gains largely into needle production or roots, or both, at the expense of growth of aboveground woody parts. This carbon allocation pattern, which resulted in the construction of exploitative root networks, appeared to be a positive growth response to the nutrient-poor permafrost soil of central Siberia.
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Above- and Belowground Biomass and net primary productivity of a Larix gmelinii stand near Tura, central Siberia
Tree physiology, 1999Co-Authors: Takuya Kajimoto, Yojiro Matsuura, Mark A Sofronov, A V Volokitina, Shigeta Mori, Akira Osawa, A P AbaimovAbstract:We assessed above- and Belowground Biomass and net primary production (NPP) of a mature Larix gmelinii (Rupr.) Rupr. forest (240-280 years old) established on permafrost soils in central Siberia. Specifically, we investigated annual carbon budgets in roots in relation to root system development and availability of soil resources. Total stand Biomass estimated by allometry was about 39 Mg per ha. Root Biomass (17 Mg per ha) comprised about 43% of total Biomass. Coarse root (>/= 5 mm in diameter) Biomass was about twice that of fine roots (< 5 mm). The aboveground Biomass/root Biomass ratio (T/R) of the larch stand was about unity, which is much less than that of other boreal and subalpine conifer forests. The proportion of fine roots in total root Biomass (35%) was relatively high compared with other cold-climate evergreen conifer forests. Total NPP, defined as the sum of annual Biomass increment of woody parts and needle Biomass, was estimated to be 1.8 Mg per ha per year. Allocation of total NPP to needle production was 56%. The proportion of total NPP in Belowground production (27%) was less than for evergreen taiga forests. However, Belowground NPP was probably under-estimated because root mortality was excluded. We conclude that L. gmelinii trees invested annual carbon gains largely into needle production or roots, or both, at the expense of growth of aboveground woody parts. This carbon allocation pattern, which resulted in the construction of exploitative root networks, appeared to be a positive growth response to the nutrient-poor permafrost soil of central Siberia.
Yuanhe Yang - One of the best experts on this subject based on the ideXlab platform.
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above and Belowground Biomass allocation in shrub biomes across the northeast tibetan plateau
PLOS ONE, 2016Co-Authors: Yuanhe Yang, Lucun Yang, Guoying ZhouAbstract:Biomass partitioning has been explored across various biomes. however, the strategies of allocation in plants still remain contentious. this study investigated allocation patterns of above-and Belowground Biomass at the community level, using Biomass survey from the tibetan plateau. we explored above-and Belowground Biomass by conducting three consecutive sampling campaigns across shrub biomes on the northeast tibetan plateau during 2011-2013. we then documented the above-ground Biomass (agb), below-ground Biomass (bgb) and root: shoot ratio (r/s) and the relationships between r/s and environment factors using data from 201 plots surveyed from 67 sites. we further examined relationships between above-ground and below-ground Biomass across various shrub types. our results indicated that the median values of agb, bgb, and r/s in tibetan shrub were 1102.55, 874.91 g m(-2), and 0.85, respectively. r/s showed significant trend with mean annual precipitation (map), while decreased with mean annual temperature (mat). reduced major axis analysis indicated that the slope of the log-log relationship between above-and Belowground Biomass revealed a significant difference from 1.0 over space, supporting the optimal hypothesis. interestingly, the slopes of the allometric relationship between log agb and log bgb differed significantly between alpine and desert shrub. our findings supported the optimal theory of above-and Belowground Biomass partitioning in tibetan shrub, while the isometric hypothesis for alpine shrub at the community level.
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above and Belowground Biomass allocation in tibetan grasslands
Journal of Vegetation Science, 2009Co-Authors: Yuanhe Yang, Jingyun Fang, Chengjun JiAbstract:Question: Optimal partitioning and isometric allocation are two important hypotheses in plant Biomass allocation. We tested these two hypotheses at the community level, using field observations from Tibetan grasslands. Location: Qinghai-Tibetan Plateau, China. Methods: We investigated allocation between above- and Belowground Biomass in alpine grasslands and its relationship with environmental factors using data collected from 141 sites across the plateau during 2001-2005. We used reduced major axis (RMA) regression and general linear models (GLM) to perform data analysis. Results: The median values of aboveground Biomass (MA), Belowground Biomass (MB), and root:shoot (R:S) ratio in alpine grasslands were 59.7, 330.5 g m−2, and 5.8, respectively. About 90% of total root Biomass occurred in the top 30 cm of soil, with a larger proportion in the alpine meadow than in the alpine steppe (96 versus 86%). As soil nitrogen and soil moisture increased, both MA and MB increased, but R:S ratio did not show a significant change. MA scaled as 0.92 the power of MB, with 95% confidence intervals of 0.82-1.02. The slope of the isometric relationship between log MA and log MB did not differ significantly between alpine steppe and alpine meadow. The isometric relationship was also independent of soil nitrogen and soil moisture. Conclusions: Our results support the isometric allocation hypothesis for the MA versus MB relationship in Tibetan grasslands.
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Above- and Belowground Biomass in relation to environmental factors in temperate grasslands, Inner Mongolia.
Science in China. Series C Life sciences, 2008Co-Authors: Yuanhe Yang, Hui Zeng, Jingyun FangAbstract:Above- and Belowground Biomasses of grasslands are important parameters for characterizing regional and global carbon cycles in grassland ecosystems. Compared with the relatively detailed information for aboveground Biomass (AGB), Belowground Biomass (BGB) is poorly reported at the regional scales. The present study, based on a total of 113 sampling sites in temperate grassland of the Inner Mongolia, investigated regional distribution patterns of AGB, BGB, vertical distribution of roots, and their relationships with environmental factors. AGB and BGB increased from the southwest to the northeast of the study region. The largest Biomass occurred in meadow steppe, with mean AGB and BGB of 196.7 and 1385.2 g/m2, respectively; while the lowest Biomass occurred in desert steppe, with an AGB of 56.6 g/m2 and a BGB of 301.0 g/m2. In addition, about 47% of root Biomass was distributed in the top 10 cm soil. Further statistical analysis indicated that precipitation was the primary determinant factor in shaping these distribution patterns. Vertical distribution of roots was significantly affected by precipitation, while the effects of soil texture and grassland types were weak.
Takuya Kajimoto - One of the best experts on this subject based on the ideXlab platform.
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above and Belowground Biomass and net primary productivity of a larix gmelinii stand near tura central siberia
Tree Physiology, 1999Co-Authors: Takuya Kajimoto, Yojiro Matsuura, Mark A Sofronov, A V Volokitina, Shigeta Mori, Akira Osawa, A P AbaimovAbstract:We assessed above- and Belowground Biomass and net primary production (NPP) of a mature Larix gmelinii (Rupr.) Rupr. forest (240-280 years old) established on permafrost soils in central Siberia. Specifically, we investigated annual carbon budgets in roots in relation to root system development and availability of soil resources. Total stand Biomass estimated by allometry was about 39 Mg ha −1 . Root Biomass (17 Mg ha −1 ) comprised about 43% of total Biomass. Coarse root (≥ 5 mm in diameter) Biomass was about twice that of fine roots (< 5 mm). The aboveground Biomass/root Biomass ratio (T/R) of the larch stand was about unity, which is much less than that of other boreal and subalpine conifer forests. The proportion of fine roots in total root Biomass (35%) was relatively high compared with other cold-climate evergreen conifer forests. Total NPP, defined as the sum of annual Biomass increment of woody parts and needle Biomass, was estimated to be 1.8 Mg ha −1 year −1 . Allocation of total NPP to needle production was 56%. The proportion of total NPP in Belowground production (27%) was less than for evergreen taiga forests. However, Belowground NPP was probably underestimated because root mortality was excluded. We conclude that L. gmelinii trees invested annual carbon gains largely into needle production or roots, or both, at the expense of growth of aboveground woody parts. This carbon allocation pattern, which resulted in the construction of exploitative root networks, appeared to be a positive growth response to the nutrient-poor permafrost soil of central Siberia.
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Above- and Belowground Biomass and net primary productivity of a Larix gmelinii stand near Tura, central Siberia
Tree physiology, 1999Co-Authors: Takuya Kajimoto, Yojiro Matsuura, Mark A Sofronov, A V Volokitina, Shigeta Mori, Akira Osawa, A P AbaimovAbstract:We assessed above- and Belowground Biomass and net primary production (NPP) of a mature Larix gmelinii (Rupr.) Rupr. forest (240-280 years old) established on permafrost soils in central Siberia. Specifically, we investigated annual carbon budgets in roots in relation to root system development and availability of soil resources. Total stand Biomass estimated by allometry was about 39 Mg per ha. Root Biomass (17 Mg per ha) comprised about 43% of total Biomass. Coarse root (>/= 5 mm in diameter) Biomass was about twice that of fine roots (< 5 mm). The aboveground Biomass/root Biomass ratio (T/R) of the larch stand was about unity, which is much less than that of other boreal and subalpine conifer forests. The proportion of fine roots in total root Biomass (35%) was relatively high compared with other cold-climate evergreen conifer forests. Total NPP, defined as the sum of annual Biomass increment of woody parts and needle Biomass, was estimated to be 1.8 Mg per ha per year. Allocation of total NPP to needle production was 56%. The proportion of total NPP in Belowground production (27%) was less than for evergreen taiga forests. However, Belowground NPP was probably under-estimated because root mortality was excluded. We conclude that L. gmelinii trees invested annual carbon gains largely into needle production or roots, or both, at the expense of growth of aboveground woody parts. This carbon allocation pattern, which resulted in the construction of exploitative root networks, appeared to be a positive growth response to the nutrient-poor permafrost soil of central Siberia.