H+ budget in a Subtropical Evergreen Broad-Leaved Forest in Southern China

Paleoecological data from Poyang Lake, southern China, indicate that significant natural and human-induced vegetational changes have occurred during the Late Quaternary in the Middle Yangtze River valley, the likely location of rice (Oryza sativa L.) domestication. During the late Pleistocene (from ca. 12,830 to ca. 10,500 yr B.P.), the climate was cooler and drier than today's. The subtropical, mixed deciduous–evergreen broad-leaved forest which constitutes the modern, potential vegetation was reduced and herbaceous vegetative cover expanded. A hiatus in sedimentation occurred in Poyang Lake, beginning sometime after ca. 10,500 yr B.P. and lasting until the middle Holocene (ca. 4000 yr B.P.). At ca. 4000 yr B.P., the regional vegetation was a diverse, broad-leaved forest dominated by many of the same arboreal elements (e.g., Quercus, Castanopsis, Liquidambar) that grow in the area today. A significant reduction of arboreal pollen and an increase of herbaceous pollen at ca. 2000 yr B.P. probably reflect human influence on the vegetation and the expansion of intensive rice agriculture into the dryland forests near the river valleys.

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Nitrogen input <sup>15</sup>N signatures are reflected in plant <sup>15</sup>N natural abundances in subtropical forests in China

Biogeosciences ◽

10.5194/bg-14-2359-2017 ◽

2017 ◽

Vol 14 (9) ◽

pp. 2359-2370 ◽

Cited By ~ 8

Author(s):

Geshere Abdisa Gurmesa ◽

Xiankai Lu ◽

Per Gundersen ◽

Yunting Fang ◽

Qinggong Mao ◽

...

Keyword(s):

Southern China ◽

N Deposition ◽

Pine Forest ◽

N Cycling ◽

N Addition ◽

Inorganic N ◽

Subtropical Forests ◽

Broad Leaved Forest ◽

Soil Δ15n ◽

Leaved Forest

Abstract. Natural abundance of 15N (δ15N) in plants and soils can provide time-integrated information related to nitrogen (N) cycling within ecosystems, but it has not been well tested in warm and humid subtropical forests. In this study, we used ecosystem δ15N to assess effects of increased N deposition on N cycling in an old-growth broad-leaved forest and a secondary pine forest in a high-N-deposition area in southern China. We measured δ15N of inorganic N in input and output fluxes under ambient N deposition, and we measured N concentration (%N) and δ15N of major ecosystem compartments under ambient deposition and after decadal N addition at 50 kg N ha−1yr−1, which has a δ15N of −0.7 ‰. Our results showed that the total inorganic N in deposition was 15N-depleted (−10 ‰) mainly due to high input of strongly 15N-depleted NH4+-N. Plant leaves in both forests were also 15N-depleted (−4 to −6 ‰). The broad-leaved forest had higher plant and soil %N and was more 15N-enriched in most ecosystem compartments relative to the pine forest. Nitrogen addition did not significantly affect %N in the broad-leaved forest, indicating that the ecosystem pools are already N-rich. However, %N was marginally increased in pine leaves and significantly increased in understory vegetation in the pine forest. Soil δ15N was not changed significantly by the N addition in either forest. However, the N addition significantly increased the δ15N of plants toward the 15N signature of the added N, indicating incorporation of added N into plants. Thus, plant δ15N was more sensitive to ecosystem N input manipulation than %N in these subtropical forests. We interpret the depleted δ15N of plants as an imprint from the high and 15N-depleted N deposition that may dominate the effects of fractionation that are observed in most warm and humid forests. Fractionation during the steps of N cycling could explain the difference between negative δ15N in plants and positive δ15N in soils, and the increase in soil δ15N with depths. Nevertheless, interpretation of ecosystem δ15N from high-N-deposition regions needs to include data on the deposition 15N signal.

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Effects of simulated acid rain on soil and soil solution chemistry in a monsoon evergreen broad-leaved forest in southern China

Environmental Monitoring and Assessment ◽

10.1007/s10661-015-4492-8 ◽

2015 ◽

Vol 187 (5) ◽

Cited By ~ 25

Author(s):

Qingyan Qiu ◽

Jianping Wu ◽

Guohua Liang ◽

Juxiu Liu ◽

Guowei Chu ◽

...

Keyword(s):

Acid Rain ◽

Soil Solution ◽

Southern China ◽

Simulated Acid Rain ◽

Solution Chemistry ◽

Soil Solution Chemistry ◽

Broad Leaved Forest ◽

Leaved Forest

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A climate change-induced threat to the ecological resilience of a subtropical monsoon evergreen broad-leaved forest in Southern China

Global Change Biology ◽

10.1111/gcb.12128 ◽

2013 ◽

Vol 19 (4) ◽

pp. 1197-1210 ◽

Cited By ~ 88

Author(s):

Guoyi Zhou ◽

Changhui Peng ◽

Yuelin Li ◽

Shizhong Liu ◽

Qianmei Zhang ◽

...

Keyword(s):

Climate Change ◽

Southern China ◽

Ecological Resilience ◽

Broad Leaved Forest ◽

Leaved Forest

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Aboveground Biomass Allometric Models for Evergreen Broad-Leaved Forest Damaged by a Serious Ice Storm in Southern China

Forests ◽

10.3390/f11030320 ◽

2020 ◽

Vol 11 (3) ◽

pp. 320

Author(s):

Houben Zhao ◽

Zhaojia Li ◽

Guangyi Zhou ◽

Zhijun Qiu ◽

Zhongmin Wu

Keyword(s):

Aboveground Biomass ◽

Southern China ◽

Management Strategies ◽

Forest Damage ◽

Diameter Distribution ◽

Ice Storm ◽

Allometric Models ◽

Broad Leaved Forest ◽

Biomass Loss ◽

Leaved Forest

A catastrophic ice storm occurred in the spring of 2008, which severely destroyed nearly 13% of China’s forests; among them, the broad-leaved forest suffered the most extensive damage. In this study, allometric models of the evergreen broad-leaved forests damaged at different recovery stages after the disaster were established to estimate the aboveground biomass of damaged trees. Plant plots were established and surveyed in damaged forests to determine species composition and diameter distribution, and finally a sample scheme was formulated that contained 47 trees from 13 species. The destructive measurements of aboveground biomass of trees selected according to the scheme were conducted in 2008, 2010, 2012 and 2016, respectively. Undamaged trees in the same region were also selected to measure the biomass in 2010. Linear regression of logarithmic transformation of the power function form was performed using Diameter at Breast Height (DBH) as predictor to develop biomass allometric models. The results showed that the ice storm caused tree aboveground biomass loss, which caused different parameters of the tree biomass models at different recovery stages. The models have a high accuracy in predicting trunk and total aboveground biomass, with high determination coefficients (R2, 0.913~0.984, mean 0.957), and have a relatively low accuracy in predicting the biomass of branches and leaves (R2, 0.703~0.892, mean 0.784). The aboveground biomass reduced by 35.0% on average due to the ice storm, and recovered to the same level of undamaged trees in the same diameter 8 years after the disturbance. The branches and leaves recovered very fast, and the biomass of these parts exceeded that of the undamaged trees, reaching the same diameter 2 years after the disaster, indicating an over compensatory growth. The trees with a smaller diameter were mostly composed of middle and late succession species, and recovered faster than other species, indicating that the ice storm may alter the forest structure and accelerate community succession. The biomass allometric models built in this study, combined with forest inventory data, can estimate forest biomass loss and recovery after disturbance, and offer an important sense of the assessment of forest damage and the formulation of forest post-disaster management strategies.

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