Find research datasets worth reusing

opencc-zeroDec 2016View details →

Data from: Soil carbon response to woody plant encroachment: Importance of spatial heterogeneity and deep soil storage

1. Recent global trends of increasing woody plant abundance in grass-dominated ecosystems may substantially enhance soil organic carbon (SOC) storage and could represent a strong carbon (C) sink in the terrestrial environment. However, few studies have quantitatively addressed the influence of spatial heterogeneity of vegetation and soil properties on SOC storage at the landscape scale. In addition, most studies assessing SOC response to woody encroachment consider only surface soils, and have not explicitly assessed the extent to which deeper portions of the soil profile may be sequestering C. 2. We quantified the direction, magnitude, and pattern of spatial heterogeneity of SOC in the upper 1.2 m of the profile following woody encroachment via spatially-specific intensive soil sampling across a landscape in a subtropical savanna in the Rio Grande Plains, USA, that has undergone woody proliferation during the past century. 3. Increased SOC accumulation following woody encroachment was observed to considerable depth, albeit at reduced magnitudes in deeper portions of the profile. Overall, woody clusters and groves accumulated 12.87 and 18.67 Mg C ha-1 more SOC compared to grasslands to a depth of 1.2 m. 4. Woody encroachment significantly altered the pattern of spatial heterogeneity of SOC to a depth of 5 cm, with marginal effect at 5-15 cm, and no significant impact on soils below 15 cm. Fine root density explained greater variability of SOC in the upper 15 cm, while a combination of fine root density and soil clay content accounted for more of the variation in SOC in soils below 15 cm across this landscape. 5. Synthesis: Substantial SOC sequestration can occur in deeper portions of the soil profile following woody encroachment. Furthermore, vegetation patterns and soil properties influenced the spatial heterogeneity and uncertainty of SOC in this landscape, highlighting the need for spatially specific sampling that can characterize this variability and enable scaling and modeling. Given the geographic extent of woody encroachment on a global scale, this undocumented deep soil C sequestration suggests this vegetation change may play a more significant role in regional and global C sequestration than previously thought.

opencc-zeroFeb 2020View details →

Frequent burning causes large losses of carbon from deep soil layers in a temperate savanna

1. Fire activity is changing dramatically across the globe, with uncertain effects on ecosystem processes, especially belowground. Fire‐driven losses of soil carbon (C) are often assumed to occur primarily in the upper soil layers because the repeated combustion of aboveground biomass limits organic matter inputs into surface soil. However, C losses from deeper soil may occur if frequent burning reduces root biomass inputs of C into deep soil layers or stimulates losses of C via leaching and priming. 2. To assess the effects of fire on soil C, we sampled 12 plots in a 51‐year‐long fire frequency manipulation experiment in a temperate oak savanna, where variation in prescribed burning frequency has created a gradient in vegetation structure from closed‐canopy forest in unburned plots to open‐canopy savanna in frequently burned plots. 3. Soil C stocks were non‐linearly related to fire frequency, with soil C peaking in savanna plots burned at an intermediate fire frequency and declining in the most frequently burned plots. Losses from deep soil pools were significant, with the absolute difference between intermediately burned plots versus. most frequently burned plots more than doubling when the full 1 m sample was considered rather than the top 0–20 cm alone (losses of 98.5 MgC ha‐1 (−76%) and 42.3 MgC ha‐1 (−68%) in the full 1 m and 0–20 cm layers, respectively). Compared to unburned forested plots, the most frequently burned plots had 65.8 MgC ha‐1 (−58%) less C in the full 1 m sample. Root biomass below the top 20 cm also declined by 39% with more frequent burning. Concurrent fire‐driven losses of nitrogen and gains in calcium and phosphorus suggest that burning may increase nitrogen limitation and play a key role in the calcium and phosphorus cycles in temperate savannas. 4. Synthesis: Our results illustrate that fire‐driven losses in soil C and root biomass in deep soil layers may be critical factors regulating the net effect of shifting fire regimes on ecosystem C in forest‐savanna transitions. Projected changes in soil C with shifting fire frequencies in savannas may be 50% too low if they only consider changes in the topsoil.

opencc-zeroOct 2022View details →

Spatio-temporal variation in deep soil water use patterns of overstory and understory layers in subtropical plantations predict community assembly

1. Deep soil water utilization allows plants to cope with drought stress. However, little is known about the roles of the understory layers in driving spatio-temporal variations of deep soil water in forests and how the patterns of deep soil water use among life forms contribute to community assembly processes. 2. We assessed the spatio-temporal patterns and determinants of deep water utilization of tree, shrub and herb layers in subtropical coniferous plantations and investigated associations between deep water use parameters and dominance and richness of understory vegetation. 3. We found that the understory layer had a higher reliance on deep soil water in the dry season, a larger seasonal plasticity of deep soil water uptake, but lower spatial variability in deep soil water utilization than the tree layer. We showed that greater reliance of the tree layer on deep soil water was associated with decreased shrub layer diversity, whereas greater reliance of the shrub layer on deep water was associated with increased herb layer diversity. 4. Synthesis. Our results highlight the roles of understory layers in driving the temporal dynamics of deep soil water in forests and improve our understanding of how deep soil water use patterns amongst life forms shape community assembly in forests.

opencc-by-4.0Oct 2022View details →

The natural abundance of stable water isotopes method may overestimate deep-layer soil water use by trees

The dataset is the basic data of the author's paper 'The natural abundance of stable water isotopes method may overestimate deep-layer soil water use by trees'. The main content of this paper is to study the water use strategy of trees in deep vadose zone regions by first identifying the soil layer depths from which trees derive their water source using isotopic labeling in deep layers and then calculating water sources based on the natural abundance of stable isotopes. We also compared the results with the natural abundance of stable water isotopes method. Taking apple plantation as an example, the data set includes the soil moisture, isotopic value in soil water, xylem water and precipitation.

Figure 4 in Deep soil floatation in Chile reveals diverse and mainly nameless fauna of endogean beetles (Coleoptera)

Figure 4. SEM images of endogean non-Staphylinidae beetles of Chile.

Figure 5 in Deep soil floatation in Chile reveals diverse and mainly nameless fauna of endogean beetles (Coleoptera)

Figure 5. SEM images of endogean rove beetles (Staphylinidae) of Chile.

Figure 3 in Deep soil floatation in Chile reveals diverse and mainly nameless fauna of endogean beetles (Coleoptera)

Figure 3. Endogean rove beetles (Staphylinidae) of Chile.

Figure 2 in Deep soil floatation in Chile reveals diverse and mainly nameless fauna of endogean beetles (Coleoptera)

Figure 2. Endogean non-Staphylinidae beetles of Chile.

opencc-by-4.0Jun 2024View details →

Hybrid deep learning framework for evaluating field evapotranspiration considering the impact of soil salinity

Entitled “A novel hybrid deep learning framework for evaluating field evapotranspiration considering the impact of soil salinity” for possible publication in Water Resources Research. Data: The Salinized Farmland Flux Station sites are located in the typical irrigated agricultural area of the arid continental monsoon region in northwest China.In this study, we used data from four flux tower located in saline farmland: two for maize (MZ1, MZ2) and two for sunflower (SF1, SF2). For each site, we collected the following variables at half-hourly temporal resolution: (i) latent heat (LE, W m-2) fluxes, serving as a direct measure representing the energy component of ET (mm h-1), (ii) net radiation (Rn, W m-2), (iii) ground heat flux (G, W m-2), (iv) solar irradiance (Rs, W m-2), (v) air temperature (Ta, °C), (vi) vapor pressure deficit (VPD, KPa), (vii) wind speed (Us, m s-1), (viii) relative humidity (RH, %), and (ix) atmospheric carbon dioxide concentration (Ca, mg m-3). During the crop growth period, field in-situ measurements of soil and vegetation data from these farmlands are conducted approximately every 10 days.   Code: All the codes were executed in Python. The provided hybrid deep learning model code can be run on Jupyter Notebook.