Functional traits drive the difference in soil respiration between Gilbertiodendron dewevrei monodominant forests patches and Scorodophloeus zenkeri mixed forests patches in the Central Congo basin.

Soil respiration is one of the main fluxes in the global carbon cycle. The effect of temperature on soil respiration is well understood. The response of soil respiration to temperature warming is called apparent temperature sensitivity (Q10) of soil respiration, which is an important parameter in modeling soil CO2 effluxes under global climate warming. The difference of Q10 between daytime and nighttime was hardly reported although attentions are attracted by the differences of temperature change and its effects on vegetation productivity. In this study, we investigated the Q10 of soil respiration in daytime and nighttime by modeling empirical functions based on the in situ measurement of soil respiration and temperature in temperate and subtropical forests of eastern China. Our results showed that the Q10 of soil respiration is higher in nighttime with the mean value of 2.74 and 2.35 than daytime with the average of 2.49 and 2.18 in all measured months and growing season, respectively. Moreover, the explanatory rate of soil temperature to soil respiration in nighttime is also higher than in daytime in each site in both all measured and growing seasons. The Q10 and explanatory rate of soil temperature to soil respiration in nighttime is 1.08 and 1.15 times in daytime in growing season. These findings indicate that soil respiration has a bigger sensitivity to temperature in nighttime than daytime. The change of soil temperature explains more variation of soil respiration in nighttime than daytime.

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The role of vegetation in the CO2 flux from a tropical urban neighbourhood

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-10185-2013 ◽

2013 ◽

Vol 13 (20) ◽

pp. 10185-10202 ◽

Cited By ~ 37

Author(s):

E. Velasco ◽

M. Roth ◽

S. H. Tan ◽

M. Quak ◽

S. D. A. Nabarro ◽

...

Keyword(s):

Soil Respiration ◽

Anthropogenic Activities ◽

Co2 Flux ◽

Accurate Estimation ◽

Urban Vegetation ◽

Co2 Uptake ◽

Total Contribution ◽

The Difference ◽

Residential Neighbourhood

Abstract. Urban surfaces are usually net sources of CO2. Vegetation can potentially have an important role in reducing the CO2 emitted by anthropogenic activities in cities, particularly when vegetation is extensive and/or evergreen. A direct and accurate estimation of carbon uptake by urban vegetation is difficult due to the particular characteristics of the urban ecosystem and high variability in tree distribution and species. Here, we investigate the role of urban vegetation in the CO2 flux from a residential neighbourhood in Singapore using two different approaches. CO2 fluxes measured directly by eddy covariance are compared with emissions estimated from emissions factors and activity data. The latter includes contributions from vehicular traffic, household combustion, soil respiration and human breathing. The difference between estimated emissions and measured fluxes should approximate the flux associated with the aboveground vegetation. In addition, a tree survey was conducted to estimate the annual CO2 sequestration using allometric equations and an alternative model of the metabolic theory of ecology for tropical forests. Palm trees, banana plants and turfgrass were also included in the survey with their annual CO2 uptake obtained from published growth rates. Both approaches agree within 2% and suggest that vegetation sequesters 8% of the total emitted CO2 in the residential neighbourhood studied. An uptake of 1.4 ton km−2 day−1 (510 ton km−2 yr−1) was estimated as the difference between assimilation by photosynthesis minus the aboveground biomass respiration during daytime (4.0 ton km−2 day−1) and release by plant respiration at night (2.6 ton km−2 day−1). However, when soil respiration is added to the daily aboveground flux, the biogenic component becomes a net source amounting to 4% of the total CO2 flux and represents the total contribution of urban vegetation to the carbon flux to the atmosphere.

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Comparison of static and dynamic closed chambers for measurement of soil respiration under field conditions

Canadian Journal of Soil Science ◽

10.4141/cjss92-050 ◽

1992 ◽

Vol 72 (4) ◽

pp. 605-609 ◽

Cited By ~ 65

Author(s):

P. Rochette ◽

E. G. Gregorich ◽

R. L. Desjardins

Keyword(s):

Soil Respiration ◽

Sandy Loam ◽

Flux Measurement ◽

Organic Soil ◽

Exponential Model ◽

Field Conditions ◽

Parameter Estimates ◽

Static Chamber ◽

The Difference ◽

Negative Exponential

The objective of this study was to compare the dynamic closed and static chamber techniques for the measurement of soil respiration under field conditions. The static chamber method consistently produced lower soil respiration values than did the dynamic closed system and the difference was larger at higher CO2 fluxes. A negative exponential model describes the relation between CO2 fluxes measured by both techniques. A good fit was obtained for measurements on a sandy loam soil (R2 = 0.61) and an organic soil (R2 = 0.74) but parameter estimates were different for each soil. Key words: Carbon dioxide, enclosure, gas flux measurement

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Effects of forest types on leaf functional traits and their interrelationships of Pinus massoniana coniferous and broad‐leaved mixed forests in the subtropical mountain, Southeastern China

Ecology and Evolution ◽

10.1002/ece3.5259 ◽

2019 ◽

Vol 9 (12) ◽

pp. 6922-6932 ◽

Cited By ~ 3

Author(s):

Juan Qin ◽

Zhouping Shangguan

Keyword(s):

Functional Traits ◽

Pinus Massoniana ◽

Forest Types ◽

Southeastern China ◽

Mixed Forests ◽

Leaf Functional Traits

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Description of a dynamic closed chamber for measuring soil respiration and its comparison with other techniques

Canadian Journal of Soil Science ◽

10.4141/s96-110 ◽

1997 ◽

Vol 77 (2) ◽

pp. 195-203 ◽

Cited By ~ 90

Author(s):

P. Rochette ◽

B. Ellert ◽

E. G. Gregorich ◽

R. L. Desjardins ◽

E. Pattey ◽

...

Keyword(s):

Carbon Dioxide ◽

Soil Respiration ◽

Field Measurements ◽

Eddy Correlation ◽

Carbon Dioxide Exchange ◽

Closed Chamber ◽

Dynamic Chamber ◽

New Information ◽

The Difference ◽

Good Agreement

Soil respiration is an important component of the net carbon dioxide exchange between agricultural ecosystems and the atmosphere, and reliable estimates of soil respiration are required in carbon balance studies. Most of the field measurements of soil respiration reported in the literature have been made using alkali traps. The use of portable CO2 analysers in dynamic closed chamber systems is recent. The introduction of this new technique requires its evaluation against existing methods in order to compare new information with older data. Nine intercomparisons between dynamic systems and alkali traps were made. Measurements of Fc,s obtained by both chambers showed a good agreement in all but two comparisons in which alkali trap measurements were lower than the dynamic chamber by about 22%. This first report of agreement between both techniques suggests that many measurements made in the past using alkali traps may be comparable to the measurements made more recently using the dynamic chambers. Analysis of the soil temperature and CO2 concentration inside the alkali traps failed to explain why the alkali traps occasionally underestimated the fluxes. Soil respiration measured with a dynamic closed chamber were also compared to eddy-correlation measurements. The results did not reveal any consistent bias between techniques but the scattering was large. This dispersion is likely the result of the difference between the areas measured by the two techniques. Key words: Carbon dioxide, greenhouse gases, CO2 flux, soil carbon

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New species of Synodontella (Monogenea, Ancyrocephalidae) gill parasites of two Synodontis spp. (Pisces, Mochokidae) from the Boumba River (Congo Basin, East Cameroon)

Parasite ◽

10.1051/parasite/2019037 ◽

2019 ◽

Vol 26 ◽

pp. 37 ◽

Cited By ~ 2

Author(s):

Jonathan A. Mbondo ◽

Jacques Nack ◽

Arnold R. Bitja Nyom ◽

Antoine Pariselle ◽

Charles F. Bilong Bilong

Keyword(s):

New Species ◽

Accessory Piece ◽

Copulatory Organ ◽

The Other ◽

Congo Basin ◽

Thin Tube ◽

The Difference ◽

Three New Species ◽

Gill Parasites ◽

Parasite Populations

Three new species of Synodontella Dossou & Euzet, 1993 are described from two species of Synodontis (Mochokidae) collected from the middle course of the Boumba River (East Cameroon): Synodontella angustupenis n. sp. from Synodontis nummifer, Synodontella longipenis n. sp. and Synodontella simplex n. sp. from Synodontis decorus. These new species are different from the other Synodontella species already described due to their horseshoe-shaped dorsal transverse bars. Synodontella angustupenis differs from S. longipenis and S. simplex by the morphology of its penis, a thin tube, and its accessory piece, bifid at its extremity. Synodontella longipenis differs from the other two species by the morphology and the size of its male copulatory organ, which is very long. Synodontella simplex differs from S. angustupenis and S. longipenis by the shape of its penis, which is simple, and of its accessory piece, with a developed heel. The difference between the dorsal transverse bars of Synodontella species from the Sanaga River in Cameroon (and other localities in Africa), slightly curved, and those from the Boumba River, horseshoe-shaped, makes it possible to separate Synodontella species into two different subgroups. This difference can be explained by a long isolation period of the hosts, living in different river basins, followed by the divergence of the parasite populations (vicariant speciation).

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Interpreting the Difference in Magnitudes of PETM Carbon Isotope Excursions in Paleosol Carbonate and Organic Matter: Oxidation of Methane in Soils Versus Elevated Soil Respiration Rates

Paleoceanography and Paleoclimatology ◽

10.1029/2019pa003596 ◽

2019 ◽

Vol 34 (12) ◽

pp. 2113-2128

Author(s):

Timothy M. Gallagher ◽

Christopher G. Cacciatore ◽

Daniel O. Breecker

Keyword(s):

Organic Matter ◽

Soil Respiration ◽

Carbon Isotope ◽

Respiration Rates ◽

Oxidation Of Methane ◽

Organic Matter Oxidation ◽

The Difference

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Diversity and abundance of ants (Hymenoptera: Formicidae) in Phu Luong, Thai Nguyen province, Vietnam

Journal of Vietnamese Environment ◽

10.13141/jve.vol8.no1.pp45-49 ◽

2016 ◽

Vol 8 (1) ◽

pp. 45-49

Author(s):

Dai Dac Nguyen ◽

Lien Thi Phuong Nguyen

Keyword(s):

Species Diversity ◽

Dominant Species ◽

Secondary Forest ◽

Diversity Index ◽

Pitfall Traps ◽

Species Diversity Index ◽

Anoplolepis Gracilipes ◽

Mixed Forests ◽

Species Similarity ◽

The Difference

Three different habitats: secondary forest, acacia plantation, and mixed forests on limestone, were chosen to determine and compare the ant species diversity in these habitats. A total of 24 identified species and 11 morphology species belonging to 20 genera in seven subfamilies were collected using pitfall traps from June 2014 to May 2015. The Shannon-Wiener’s species diversity index indicated that the diversity was the highest in the acacia plantation (2.08), followed by the secondary forest (1.99) and lowest in the mixed forests on limestone (1.83). There are three dominant species in the habitat (I), Pheidole noda, Odontomachus cf. monticola, and Odontoponera denticulate; four dominant species in the habitat (II), Odontoponera denticulata, Carebara diversa, Technomyrmex brunneus and Anoplolepis gracilipes; and only one dominant species in the habitat (III), Anoplolepis gracilipes. The species similarity (S) relatively low may be because of the difference vegetation and condition in the three habitats. Đa dạng loài kiến trong ba môi trường sống khác nhau: rừng rậm thường xanh nhiệt đới, rừng keo và rừng hỗn giao trên núi đá vôi, được nghiên cứu để xác định và so sánh sự đa dạng các loài kiến trong những môi trường sống. Phương pháp nghiên cứu: sử dụng bẫy hố từ tháng 6 năm 2014 đến tháng 5 năm 2015. Đã ghi nhận được 35 loài, thuộc 20 giống, 7 phân họ. Chỉ số đa dạng loài Shannon-Wiener cho thấy rừng keo có chỉ số đa dạng cao nhất (2,08), tiếp theo là rừng rậm thường xanh nhiệt đới (1,99) và cuối cùng là rừng hỗn giao trên núi đá vôi (1,83). Có 3 loài ưu thế ở sinh cảnh (I) là Pheidole noda, Odontomachus cf. monticola và Odontoponera denticulata, bốn loài ưu thế ở sinh cảnh (II) là Carebara diversa, Technomyrmex brunneus, Odontoponera denticulate và Anoplolepis gracilipes. Ở sinh cảnh (III) chỉ có duy nhất một loài chiếm ưu thế là loài Anoplolepis gracilipes. Chỉ số tương đồng (S) tương đối thấp có thể là do sự khác nhau ở các thảm thực vật và điều kiện sống trong ba sinh cảnh.

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Spatial Heterogeneity of Soil Respiration Response to Precipitation Pulse in a Temperate Mixed Forest in Central China

Journal of Plant and Animal Ecology ◽

10.14302/issn.2637-6075.jpae-17-1863 ◽

2017 ◽

Vol 1 (1) ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Yanchun Liu ◽

Qing Shang ◽

Zhongwei Wang ◽

Kesheng Zhang

Keyword(s):

Soil Respiration ◽

Spatial Heterogeneity ◽

Carbon Cycling ◽

Biological Activities ◽

Mixed Forest ◽

Central China ◽

Terrestrial Carbon ◽

Size Classes ◽

The Difference ◽

Precipitation Pulse

Water availability is one of the fundamental drivers for biological activities and terrestrial carbon cycling. Although the response of soil respiration to precipitation has been well documented in arid and semiarid ecosystems, our understanding of its pattern in forests is rather limited. This study was conducted to examine the difference of precipitation effect on soil respiration under different canopy conditions in a temperate coniferous (Pinus armandii Franch) and broadleaved (Quercus aliena var. acuteserrata) mixed forest in Central China. The results showed that precipitation significantly reduced soil temperature, but increased soil volumetric water content and soil respiration (6.0%-35.3%). Precipitation caused a greater increment in soil respiration beneath the canopy of broadleaved trees (24.2%) than that beneath coniferous ones (13.5%). Precipitation-induced increase in soil respiration was consistently lower beneath the canopy of small size classes (7.1%-32.6%) than large size classes (9.5%-33.3%). Mean soil respiration of forest gaps increased 22.4% following precipitations. Our study highlights the positive response of soil respiration to precipitation pulses in water-unlimited ecosystems. The findings suggest that the spatial heterogeneity of soil respiration to precipitation pulse under different canopy conditions should be emphasized while assessing terrestrial carbon cycling and its feedback to climate change.

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