Tree species and time since afforestation drive soil C and N mineralization on former cropland

Wetlands store a large amount of carbon (C) and many are vulnerable to potential global warming. It is critical to quantify the temperature sensitivity of soil nitrogen (N) and C mineralization in response to external labile C or N addition in different types of wetland. Through incubation experiments, the effects of temperature and the addition of N or C on soil C and N mineralization were tested using soils from the Sanjiang Plain wetland (SW), Zoigê alpine wetland (ZW), Yellow River estuary wetland (YW), and Baiyangdian Lake (BL). Our findings showed that temperature, available C and wetland type were dominant factors in the regulation of soil C loss, with soil C in SW and ZW being less stable and poorly resistant to increases in temperature. The response of net N mineralization to N addition showed regional differences. A lack of long-term effects of the deposition of N on soil mineralization suggested that there may be a particular N addition threshold level for changed C and N mineralization. It is predicted that an increase in labile C supply due to elevated carbon dioxide (CO2) and its interactions with wetland types will increase CO2 efflux more than N deposition in wetland soils.

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Moisture effect on carbon and nitrogen mineralization in topsoil of Changbai Mountain, Northeast China

Journal of Forest Science ◽

10.17221/56/2010-jfs ◽

2011 ◽

Vol 57 (No. 8) ◽

pp. 340-348 ◽

Cited By ~ 11

Author(s):

G. Qi ◽

Q. Wang ◽

W. Zhou ◽

H. Ding ◽

X. Wang ◽

...

Keyword(s):

N Mineralization ◽

Northeast China ◽

Vegetation Type ◽

Changbai Mountain ◽

Annual Precipitation ◽

Soil C ◽

Natural Reserve ◽

C And N Mineralization ◽

Soil C And N ◽

C And N

Changbai Mountain Natural Reserve (1,985 km2 and 2,734 m a.s.l.) of Northeast China is a typical ecosystem representing the temperate biosphere. The vegetation is vertically divided into 4 dominant zones: broadleaved Korean pine forest (annual temperature 2.32°C, annual precipitation 703.62 mm), dark coniferous forest (annual temperature –1.78°C, annual precipitation 933.67 mm), Erman's birch forest (annual temperature –2.80°C, annual precipitation 1,002.09 mm) and Alpine tundra (annual temperature –3.82°C, annual precipitation 1,075.53 mm). Studies of soil carbon (C) and nitrogen (N) mineralization have attracted wide attention in the context of global climate change. Based on the data of a 42-day laboratory incubation experiment, this paper investigated the relationship between soil moisture and mineralization of C and N in soils with different vegetation types on the northern slope of the Natural Reserve Zone of Changbai Mountain. The elevation influence on soil C and N mineralization was also discussed. The results indicated that for the given vegetation type of Changbai Mountain the C and N mineralization rate, potential mineralizable C (C0) and potential rate of initial C mineralization (C0k) all increased as the soil moisture rose. The elevation or vegetation type partially affected the soil C and N mineralization but without a clear pattern. The moisture-elevation interaction significantly affected soil C and NO3–-N mineralization, but the effect on NH4+-N mineralization was not significant. The complex mechanism of their impact on the soil C and N mineralization of Changbai Mountain remains to be studied further based on data of field measurements in the future.

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Interactive effects of belowground organic matter input, increased precipitation and clipping on soil carbon and nitrogen mineralization in a temperate steppe

Biogeosciences Discussions ◽

10.5194/bgd-10-9493-2013 ◽

2013 ◽

Vol 10 (6) ◽

pp. 9493-9521

Author(s):

L. N. Ma ◽

C. Y. Guo ◽

X. P. Xin ◽

S. Yuan ◽

R. Z. Wang

Keyword(s):

Organic Matter ◽

N Mineralization ◽

Interactive Effects ◽

Mineralization Rate ◽

Temperate Steppe ◽

Soil Microbial Community Structure ◽

Soil C ◽

C And N Mineralization ◽

Soil C And N ◽

C And N

Abstract. Soil organic matter (SOM) inputs, increased precipitation and clipping (reducing belowground photosynthates allocation) are predicted to affect soil C and N cycling in temperate grassland ecosystems. However, the interactive effects between SOM inputs (or increased precipitation) and clipping on soil C and N mineralization in temperate steppes are still poorly understood. A field manipulation experiment was conducted to quantify the effects of SOM inputs, increased precipitation, clipping and their interactions on soil C and N mineralization in a temperate steppe of northeastern China from 2010 to 2011. The results showed that SOM inputs significantly increased soil C mineralization rate (CMR) and net N mineralization rate (NMR). Increased precipitation-induced enhancement of soil CMR essentially ceased after the first year, stimulation of soil NMR and NNR continued into the second year. However, clipping only marginally decreased soil CMR and NMR during the two years. There were significant synergistic interactions between SOM inputs (or increased precipitation) and clipping on soil CMR and NMR, as SOM inputs (or increased precipitation) showed greater effects on soil CMR and NMR under clipped plots than under unclipped plots, which could be explained by the relative shifts in soil microbial community structure because of bacterial biomass increases, and by the relative decreases in arbuscular mycorrhizal fungi biomass due to the reduction of belowground photosynthates allocation. These results highlight the importance of plants in mediating the responses of soil C and N mineralization to potentially increased SOM and precipitation by controlling belowground photosynthates allocation in the temperate steppe. Thus, the findings have important implications for improving prediction of C and N sequestration potential and its feedbacks to climate change in temperate steppe ecosystems.

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Effects of belowground litter addition, increased precipitation and clipping on soil carbon and nitrogen mineralization in a temperate steppe

Biogeosciences ◽

10.5194/bg-10-7361-2013 ◽

2013 ◽

Vol 10 (11) ◽

pp. 7361-7372 ◽

Cited By ~ 17

Author(s):

L. Ma ◽

C. Guo ◽

X. Xin ◽

S. Yuan ◽

R. Wang

Keyword(s):

Soil Carbon ◽

N Mineralization ◽

Mineralization Rate ◽

Temperate Steppe ◽

Soil Microbial Community Structure ◽

Soil C ◽

C And N Mineralization ◽

Soil C And N ◽

C And N ◽

Photosynthate Allocation

Abstract. Soil carbon (C) and nitrogen (N) cycling are sensitive to changes in environmental factors and play critical roles in the responses of terrestrial ecosystems to natural and anthropogenic perturbations. This study was conducted to quantify the effects of belowground particulate litter (BPL) addition, increased precipitation and their interactions on soil C and N mineralization in two adjacent sites where belowground photosynthate allocation was manipulated through vegetation clipping in a temperate steppe of northeastern China from 2010 to 2011. The results show that BPL addition significantly increase soil C mineralization rate (CMR) and net N mineralization rate (NMR). Although increased precipitation-induced enhancement of soil CMR essentially ceased after the first year, stimulation of soil NMR and net nitrification rate continued into the second year. Clipping only marginally decreased soil CMR and NMR during the two years. There were significant synergistic interactions between BPL addition (and increased precipitation) and clipping on soil CMR and NMR, likely to reflect shifts in soil microbial community structure and a decrease in arbuscular mycorrhizal fungi biomass due to the reduction of belowground photosynthate allocation. These results highlight the importance of plants in mediating the responses of soil C and N mineralization to potentially increased BPL and precipitation by controlling belowground photosynthate allocation in the temperate steppe.

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Simulation of protozoa-induced mineralization of bacterial carbon and nitrogen

Canadian Journal of Soil Science ◽

10.4141/cjss92-020 ◽

1992 ◽

Vol 72 (3) ◽

pp. 201-216 ◽

Cited By ~ 17

Author(s):

P. M. Rutherford ◽

N. G. Juma

Keyword(s):

N Mineralization ◽

Ecological Research ◽

Clay Loam ◽

Glucose Addition ◽

Soil C ◽

Carbon And Nitrogen ◽

Soil C And N ◽

C And N ◽

Typic Cryoboroll ◽

Bacterial C

Modelling in soil ecological research is a means of linking the dynamics of microbial and faunal populations to soil processes. The objectives of this study were (i) to simulate bacterial-protozoan interactions and flows of C and N in clay loam Orthic Black Chernozemic soil under laboratory condtions; and (ii) to quantify the flux of C and N (inputs and outputs) through various pools using the simulation model. The unique features of this model are: (i) it combines the food chain with specific soil C and N pools, and (ii) it simultaneously traces the flows of C, 14C, N and 15N. It was possible to produce a model that fitted the data observed for the soil. The simulated CO2-C evolved during the first 12 d was due mainly to glucose addition (171 μg C g−1 soil) and cycling of C in the soil (160 μg C g−1 soil). During this interval, bacterial C uptake was 5.5-fold greater than the initial bacterial C pool size. In the first 12 d protozoa directly increased total CO2-C evolution by 11% and increased NH4-N mineralization 3-fold, compared to soil containing only bacteria. Mineralization of C and N was rapid when bacterial numbers were increased as a result of glucose addition. Key words: Acanthamoeba sp., modelling, N mineralization-immobilization, organic matter, Pseudomonas sp., Typic Cryoboroll

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Modeling the effects of tree species and incubation temperature on soil's extracellular enzyme activity in 78-year-old tree plantations

Biogeosciences ◽

10.5194/bg-14-5393-2017 ◽

2017 ◽

Vol 14 (23) ◽

pp. 5393-5402 ◽

Cited By ~ 2

Author(s):

Xiaoqi Zhou ◽

Shen S. J. Wang ◽

Chengrong Chen

Keyword(s):

Tree Species ◽

Incubation Temperature ◽

N Cycling ◽

Residual Soil ◽

Coniferous Tree ◽

Soil C ◽

Hoop Pine ◽

Soil C And N ◽

C And N ◽

Coniferous Tree Species

Abstract. Forest plantations have been widely used as an effective measure for increasing soil carbon (C), and nitrogen (N) stocks and soil enzyme activities play a key role in soil C and N losses during decomposition of soil organic matter. However, few studies have been carried out to elucidate the mechanisms behind the differences in soil C and N cycling by different tree species in response to climate warming. Here, we measured the responses of soil's extracellular enzyme activity (EEA) to a gradient of temperatures using incubation methods in 78-year-old forest plantations with different tree species. Based on a soil enzyme kinetics model, we established a new statistical model to investigate the effects of temperature and tree species on soil EEA. In addition, we established a tree species–enzyme–C∕N model to investigate how temperature and tree species influence soil C∕N contents over time without considering plant C inputs. These extracellular enzymes included C acquisition enzymes (β-glucosidase, BG), N acquisition enzymes (N-acetylglucosaminidase, NAG; leucine aminopeptidase, LAP) and phosphorus acquisition enzymes (acid phosphatases). The results showed that incubation temperature and tree species significantly influenced all soil EEA and Eucalyptus had 1.01–2.86 times higher soil EEA than coniferous tree species. Modeling showed that Eucalyptus had larger soil C losses but had 0.99–2.38 times longer soil C residence time than the coniferous tree species over time. The differences in the residual soil C and N contents between Eucalyptus and coniferous tree species, as well as between slash pine (Pinus elliottii Engelm. var. elliottii) and hoop pine (Araucaria cunninghamii Ait.), increase with time. On the other hand, the modeling results help explain why exotic slash pine can grow faster, as it has 1.22–1.38 times longer residual soil N residence time for LAP, which mediate soil N cycling in the long term, than native coniferous tree species like hoop pine and kauri pine (Agathis robusta C. Moore). Our results will be helpful for understanding the mechanisms of soil C and N cycling by different tree species, which will have implications for forest management.

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Changes in the soil C and N contents, C decomposition and N mineralization potentials in a rice paddy after long-term application of inorganic fertilizers and organic matter

Soil Science & Plant Nutrition ◽

10.1080/00380768.2016.1155169 ◽

2016 ◽

Vol 62 (2) ◽

pp. 212-219 ◽

Cited By ~ 21

Author(s):

Weiguo Cheng ◽

Agnes T. Padre ◽

Chizuru Sato ◽

Hiroyuki Shiono ◽

Satoshi Hattori ◽

...

Keyword(s):

Organic Matter ◽

N Mineralization ◽

Rice Paddy ◽

Inorganic Fertilizers ◽

Soil C ◽

C Decomposition ◽

Soil C And N ◽

C And N

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Modeling the effects of tree species and temperature on soil's extracellular enzyme activity in 78-year-old tree plantations

10.5194/bg-2017-144 ◽

2017 ◽

Author(s):

Xiaoqi Zhou ◽

Shen S. J. Wang ◽

Chengrong Chen

Keyword(s):

Tree Species ◽

Soil Enzyme ◽

Residual Soil ◽

Coniferous Tree ◽

Soil C ◽

Hoop Pine ◽

Soil C And N ◽

C And N ◽

Coniferous Tree Species ◽

Over Time

Abstract. Forest plantations have been widely used as an effective measure for increasing soil carbon (C) and nitrogen (N) stocks and soil enzyme activities play a key role in soil C and N losses during decomposition of soil organic matter. However, few studies have been carried out to elucidate the mechanisms for the differences in soil C and N cycling by different tree species in response to climate warming. Here, we measured the responses of soil's extracellular enzyme activity (EEA) to a gradient of temperatures using incubation methods in 78-year-old forest plantations with different tree species. Based on a soil enzyme kinetics model, we established a new statistical model to investigate the effects of temperature and tree species on soil EEA. In addition, we established a soil–enzyme–C/N model to investigate how temperature and tree species influence soil C/N contents over time without considering plant C inputs. These extracellular enzymes included C acquisition enzymes (β-glucosidase, BG), N acquisition enzymes (N-acetylglucosaminidase, NAG; leucine aminopeptidase, LAP) and phosphorus acquisition enzymes (acid phosphatases). The results showed that temperature and tree species significantly influenced all soil EEA and Eucalyptus had higher soil EEA than coniferous tree species. Modeling showed that Eucalyptus had larger soil C losses but had longer soil C residence time than the coniferous tree species over time. The differences in the residual soil C and N contents between Eucalyptus and coniferous tree species, as well as between slash pine (Pinus elliottii Engelm. var. elliottii) and hoop pine (Araucaria cunninghamii Ait), become larger and larger over time. On the other hand, the modeling results help explain why exotic slash pine can grow faster, as it has longer residual soil N residence time than native coniferous tree species like hoop pine and kauri pine (Agathis robusta C. Moore). Our results will be helpful for understanding the mechanisms of soil C and N cycling by different tree species, which will have implications for forest management.

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