Impacts of extreme weather on mercury uptake and storage in subtropical forest ecosystems

Abstract. Tropical cyclones (typhoons/hurricanes) have major impacts on the biogeochemistry of forest ecosystems, but the stochastic nature and the long intervals between storms means that there are limited data on their effects. We characterised the impacts of 14 typhoons over six years on hydrochemistry of a subtropical forest plantation in Taiwan, a region experiencing frequent typhoons. Typhoons contributed 1/3 of the annual rainfall on average, but ranged from 4 to 55%. The stochastic nature of annual typhoon related precipitation poses a challenge with respect to managing the impacts of these extreme events. This challenge is exacerbated by the fact that typhoon-related rainfall is not significantly correlated with wind velocity, the current focus of weather forecasts. Thus, little advance warning is provided for the hydrological impacts of these storms. The typhoons we studied contributed approximately one third of the annual input and output of most nutrients (except nitrogen) during an average 9.5 day yr−1 period, resulting in nutrient input/output rates an order of magnitude greater than during non-typhoon months. Nitrate output balanced input during the non-typhoon period, but during the typhoon period an average of 10 kg ha−1 yr−1 nitrate was lost. Streamwater chemistry exhibited similarly high variability during typhoon and non-typhoon periods and returned to pre-typhoon levels one to three weeks following each typhoon. The streamwater chemistry appears to be very resilient in response to typhoons, resulting in minimal loss of nutrients.

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Responses of soil respiration to elevated carbon dioxide and nitrogen addition in young subtropical forest ecosystems in China

Biogeosciences ◽

10.5194/bg-7-315-2010 ◽

2010 ◽

Vol 7 (1) ◽

pp. 315-328 ◽

Cited By ~ 84

Author(s):

Q. Deng ◽

G. Zhou ◽

J. Liu ◽

S. Liu ◽

H. Duan ◽

...

Keyword(s):

Soil Respiration ◽

Elevated Co2 ◽

Forest Ecosystems ◽

N Deposition ◽

Subtropical Forest ◽

N Addition ◽

Above Ground Biomass ◽

Respiration Rates ◽

Ambient Co2 ◽

Ambient N Deposition

Abstract. Global climate change in the real world always exhibits simultaneous changes in multiple factors. Prediction of ecosystem responses to multi-factor global changes in a future world strongly relies on our understanding of their interactions. However, it is still unclear how nitrogen (N) deposition and elevated atmospheric carbon dioxide concentration [CO2] would interactively influence forest floor soil respiration in subtropical China. We assessed the main and interactive effects of elevated [CO2] and N addition on soil respiration by growing tree seedlings in ten large open-top chambers under CO2 (ambient CO2 and 700 μmol mol−1) and nitrogen (ambient and 100 kg N ha−1 yr−1) treatments. Soil respiration, soil temperature and soil moisture were measured for 30 months, as well as above-ground biomass, root biomass and soil organic matter (SOM). Results showed that soil respiration displayed strong seasonal patterns with higher values observed in the wet season (April–September) and lower values in the dry season (October–March) in all treatments. Significant exponential relationships between soil respiration rates and soil temperatures, as well as significant linear relationships between soil respiration rates and soil moistures (below 15%) were found. Both CO2 and N treatments significantly affected soil respiration, and there was significant interaction between elevated [CO2] and N addition (p<0.001, p=0.003, and p=0.006, respectively). We also observed that the stimulatory effect of individual elevated [CO2] (about 29% increased) was maintained throughout the experimental period. The positive effect of N addition was found only in 2006 (8.17% increased), and then had been weakened over time. Their combined effect on soil respiration (about 50% increased) was greater than the impact of either one alone. Mean value of annual soil respiration was 5.32 ± 0.08, 4.54 ± 0.10, 3.56 ± 0.03 and 3.53 ± 0.03 kg CO2 m−2 yr−1 in the chambers exposed to elevated [CO2] and high N deposition (CN), elevated [CO2] and ambient N deposition (CC), ambient [CO2] and high N deposition (NN), and ambient [CO2] and ambient N deposition (CK as a control), respectively. Greater above-ground biomass and root biomass was obtained in the CN, CC and NN treatments, and higher soil organic matter was observed only in the CN treatment. In conclusion, the combined effect of elevated [CO2] and N addition on soil respiration was apparent interaction. They should be evaluated in combination in subtropical forest ecosystems in China where the atmospheric CO2 and N deposition have been increasing simultaneously and remarkably.

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Quantifying ecological memory during forest succession: A case study from lower subtropical forest ecosystems in South China

Ecological Indicators ◽

10.1016/j.ecolind.2013.05.010 ◽

2013 ◽

Vol 34 ◽

pp. 192-203 ◽

Cited By ~ 16

Author(s):

Zhongyu Sun ◽

Hai Ren ◽

Valentin Schaefer ◽

Hongfang Lu ◽

Jun Wang ◽

...

Keyword(s):

South China ◽

Forest Ecosystems ◽

Forest Succession ◽

Subtropical Forest ◽

Ecological Memory

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Epiphytic lichens in subtropical forest ecosystems in southwest China: Species diversity and implications for conservation

Biological Conservation ◽

10.1016/j.biocon.2012.12.027 ◽

2013 ◽

Vol 159 ◽

pp. 88-95 ◽

Cited By ~ 15

Author(s):

Su Li ◽

Wen-Yao Liu ◽

Da-Wen Li

Keyword(s):

Species Diversity ◽

Forest Ecosystems ◽

Southwest China ◽

Subtropical Forest ◽

Epiphytic Lichens

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The mechanism for exclusion of Pinus massoniana during the succession in subtropical forest ecosystems: light competition or stoichiometric homoeostasis?

Scientific Reports ◽

10.1038/srep10994 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 6

Author(s):

Junhua Yan ◽

Kun Li ◽

Xingju Peng ◽

Zhongliang Huang ◽

Shizhong Liu ◽

...

Keyword(s):

Forest Ecosystems ◽

Pinus Massoniana ◽

Subtropical Forest ◽

Light Competition

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Classification of radicular biomass and monitoring of litter in Pantanal and Cerrado Mato-Grossense

Revista Ibero-Americana de Ciências Ambientais ◽

10.6008/cbpc2179-6858.2020.007.0040 ◽

2020 ◽

Vol 11 (7) ◽

pp. 501-512

Author(s):

Ana Carolina Freitas da Silva Taques ◽

Osvaldo Borges Pinto Junior ◽

George Louis Vourlities ◽

Roberta Daniela de Souza Lauxen da Silva

Keyword(s):

Root Biomass ◽

Forest Ecosystems ◽

Sensu Stricto ◽

Root Density ◽

Study Objective ◽

Monthly Average ◽

Significant Difference ◽

The Difference ◽

And Storage

The quantification of root biomass and the assessment of its dynamics in forest ecosystems has been intensified due to its important role in carbon sequestration and storage and the possible consequences under climate change conditions. In general, biomass stocks between and within forest ecosystems are highly variable. It is necessary to study all the different components of vegetation, however, the vast majority of the works found in the literature, address only the biomass of the aerial part of the plants, with few studies involving the quantification of these stocks by the roots, in the different ecosystems. The present study objective quantify and classify a root biomass with a depth of 0 to 10 cm, and to monitor accumulated litter in the soil (litter pool), in two different regions, in the Pantanal (Acurizal) and in the Cerrado (Sensu stricto) Mato-Grossense. The root biomass was obtained by means of unformed soil samples (0-10 cm) and the roots were classified by diameter, with the aid of digital calipers, between thick (> 10 mm), medium (5-10 mm), slightly thin (2-5 mm) and fine (<2 mm). The samples collected monthly between August 2018 and July 2019. Was observed that in both areas, about 90% of the roots collected, were fine (<2 mm). The root density in Acurizal was on average 124.92 g/m² and in Sensu stricto it was on average 57.5 g/m². The difference in root density in the soil, between the two study areas, significant (p<0.05). However, there no significant difference in root density between the dry and wet periods in each area. The monthly average of litter pool in the area of Acurizal and Sensu stricto was, respectively: 526.52 g/m² and 588.96 g/m². In both areas, the accumulated litter was significantly different between periods of drought and precipitation.

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Impacts of tropical cyclones on hydrochemistry of a subtropical forest

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-10-4537-2013 ◽

2013 ◽

Vol 10 (4) ◽

pp. 4537-4566 ◽

Cited By ~ 1

Author(s):

C. T. Chang ◽

S. P. Hamburg ◽

J. L. Hwong ◽

N. H. Lin ◽

M. L. Hsueh ◽

...

Keyword(s):

Tropical Cyclones ◽

Forest Ecosystems ◽

Subtropical Forest ◽

Annual Rainfall ◽

Limited Data ◽

Nutrient Input ◽

Weather Forecasts ◽

Streamwater Chemistry ◽

Stochastic Nature ◽

Order Of Magnitude

Abstract. Tropical cyclones (typhoons/hurricanes) have major impacts on the biogeochemistry of forest ecosystems, but the stochastic nature and the long intervals between storms means that there are limited data on their effects. We characterized the impacts of 14 typhoons over six years on hydrochemistry of a subtropical forest plantation in Taiwan, a region experiencing frequent typhoons. Typhoons contributed 1/3 of annual rainfall on average, but ranged from 4% to 55%. The stochastic nature of annual typhoon related precipitation poses a challenge with respect to managing the impacts of these extreme events. This challenge is exacerbated by the fact that typhoon-related rainfall is not significantly correlated with wind velocity, the current focus of weather forecasts. Thus little advance warning is provided for the hydrological impacts of these storms. The typhoons we studied contributed approximately one third of the annual input and output of most nutrients (except nitrogen) during an average 9.5d yr−1 period, resulting in nutrient input/output rates an order of magnitude greater than during non-typhoon period. Nitrate output balanced input during the non-typhoon period, but during the typhoon period an average of 10 kg ha−1 yr−1 nitrate was lost. Streamwater chemistry exhibited similarly high variability during typhoon and non-typhoon periods and returned to pre-typhoon levels one to three weeks following each typhoon. The streamwater chemistry appears to be very resilient in response to typhoons, resulting in minimal loss of nutrients.

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