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Yu Q, Li H, Zhao Y, Mulder J, Duan L. Long-term Trends of Dissolved Organic Carbon Dynamics in a Subtropical Forest Responding to Environmental Changes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 38965050 DOI: 10.1021/acs.est.3c08262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/06/2024]
Abstract
Dissolved organic carbon (DOC) dynamics are critical to carbon cycling in forest ecosystems and sensitive to global change. Our study, spanning from 2001 to 2020 in a headwater catchment in subtropical China, analyzed DOC and water chemistry of throughfall, litter leachate, soil waters at various depths, and streamwater. We focused on DOC transport through hydrological pathways and assessed the long-term trends in DOC dynamics amidst environmental and climatic changes. Our results showed that the annual DOC deposition via throughfall and stream outflow was 14.2 ± 2.2 and 1.87 ± 0.83 g C m-2 year-1, respectively. Notably, there was a long-term declining trend in DOC deposition via throughfall (-0.195 mg C L-1 year-1), attributed to reduced organic carbon emissions from clean air actions. Conversely, DOC concentrations in soil waters and stream waters showed increasing trends, primarily due to mitigated acid deposition. Moreover, elevated temperature and precipitation could partly explain the long-term rise in DOC leaching. These trends in DOC dynamics have significant implications for the stability of carbon sink in terrestrial, aquatic, and even oceanic ecosystems at regional scales.
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Affiliation(s)
- Qian Yu
- State Key Laboratory of Pollution Control & Resource Reuse and School of Environment, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Han Li
- State Key Laboratory of Pollution Control & Resource Reuse and School of Environment, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Yu Zhao
- State Key Laboratory of Pollution Control & Resource Reuse and School of Environment, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Jan Mulder
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Box 5003, NO-1432 Ås, Norway
| | - Lei Duan
- State Key Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
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Amin AEEAZ. Impact of some amendments on kinetics of leaching dissolved organic carbon and ammonium in calcareous sandy soil under vinasse addition. Sci Rep 2024; 14:4233. [PMID: 38378751 PMCID: PMC10879135 DOI: 10.1038/s41598-024-54420-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Accepted: 02/13/2024] [Indexed: 02/22/2024] Open
Abstract
The access of vinasse leachates to water bodies and groundwater exacerbates environmental problems, especially eutrophication. Therefore, a column experiment was performed to examine the effect of adding zeolite (ZL), bone char (BC), and wood chips biochar (WCB) in the presence of vinasse on carbon dioxide (CO2) emission, leaching dissolved organic carbon (DOC) and ammonium (NH4+) in calcareous sandy soil, as well as studying the kinetics of leaching dissolved organic carbon and ammonium. This column experiment contains four treatments: soil alone (CK), soil + zeolite (SZL), soil + bone char (SBC), and soil + wood chips biochar (SWCB). These amendments were applied to the soil at a level of 4%. Vinasse was added to all treatments at a level of 13 mL per column. The leached total cumulative DOC and total cumulative soluble ammonium amounts decreased significantly with applying ZL, BC, and WCB compared with the soil alone. The effectiveness of these amendments in lowering the total cumulative DOC leaching is in the order of SBC > SWCB > SZL > CK. However, the effectiveness of these amendments in decreasing the total cumulative NH4+ leaching is in the order of SZL > SWCB > SBC > CK. The rate constant (k) of DOC leaching decreased significantly with the application of bone char compared to soil alone treatment. In the presence of vinasse, the apparent half-life of leached DOC from the soil was 8.1, 12.9, 36.7, and 15.5 days for soil CK, SZL, SBC, and SWCB treatments, respectively. Half-life values of leached soluble ammonium from the soil in the presence of vinasse addition were 10.1, 39.5, 28.5, and 37.9 days for CK, SZL, SBC, and SWCB treatments, respectively. Amending soil with BC increased significantly the phosphorus availability, however, applying ZL and BC caused a significant increase in the available potassium in calcareous sandy soil compared to the control treatment. According to these results, it is recommended not to add vinasse alone to sandy soils, but it is preferred to be co-applied with BC amendment at the level of 4% better than ZL and WCB. This would decrease leaching DOC and ammonium to the water table and groundwater as well as enhance nutrient retention in the soil, which in turn, plays a vital role in reducing the harmful effect of vinasse and improving soil fertility.
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Kopáček J, Bače R, Choma M, Hejzlar J, Kaňa J, Oulehle F, Porcal P, Svoboda M, Tahovská K. Carbon and nutrient pools and fluxes in unmanaged mountain Norway spruce forests, and losses after natural tree dieback. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166233. [PMID: 37572919 DOI: 10.1016/j.scitotenv.2023.166233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 08/02/2023] [Accepted: 08/09/2023] [Indexed: 08/14/2023]
Abstract
Forest areas infected by insects are increasing in Europe and North America due to accelerating climate change. A 2000-2020 mass budget study on major elements (C, N, P, Ca, Mg, K) in the atmosphere-plant-soil-water systems of two unmanaged catchments enabled us to evaluate changes in pools and fluxes related to tree dieback and long-term accumulation/losses during the post-glacial period. A bark-beetle outbreak killed >75 % of all trees in a mature mountain spruce forest in one catchment and all dead biomass was left on site. A similar forest in a nearby catchment was only marginally affected. We observed that: (1) the long-term (millennial) C and N accumulation in soils averaged 10-22 and 0.5-1.1 kg ha-1 yr-1, respectively, while losses of Ca, Mg, and K from soils ranged from 0.1 to 2.6 kg ha-1 yr-1. (2) Only <0.8 % and <1.5 % of the respective total C and N fluxes entering the soil annually from vegetation were permanently stored in soils. (3) The post-disturbance decomposition of dead tree biomass reduced vegetation element pools from 27 % (C) to 73 % (P) between 2004 and 2019. (4) Tree dieback decreased net atmospheric element inputs to the impacted catchment, and increased the leaching of all elements and gaseous losses of C (∼2.3 t ha-1 yr-1) and N (∼14 kg ha-1 yr-1). The disturbed catchment became a net C source, but ∼50 % of the N released from dead biomass accumulated in soils. (5) Despite the severe forest disturbance, the dissolved losses of Ca and Mg represented 52-58 % of their leaching from intact stands during the peaking atmospheric acidification from 1970 to 1990. (6) Disturbance-related net leaching of P, Ca, Mg, and K were 4, 69, 16, and 114 kg ha-1, respectively, which represented 7-38 % of the losses potentially related to sanitary logging and subsequent removal of the aboveground tree biomass.
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Affiliation(s)
- Jiří Kopáček
- Biology Centre CAS, Institute of Hydrobiology, České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic.
| | - Radek Bače
- Czech University of Life Sciences, Faculty of Forestry and Wood Science, Prague, Czech Republic
| | - Michal Choma
- University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic
| | - Josef Hejzlar
- Biology Centre CAS, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Jiří Kaňa
- Biology Centre CAS, Institute of Hydrobiology, České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic
| | - Filip Oulehle
- Czech Geological Survey, Klárov 3, 11821 Prague 1, Czech Republic
| | - Petr Porcal
- Biology Centre CAS, Institute of Hydrobiology, České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic
| | - Miroslav Svoboda
- Czech University of Life Sciences, Faculty of Forestry and Wood Science, Prague, Czech Republic
| | - Karolina Tahovská
- University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic
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Li H, Jin R, Xu Z, Hu H, Kalkhajeh YK, Zhao Y, Zhan L. Application of chelate GLDA for remediating Cd-contaminated farmlands using Tagetes patula L. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:3774-3782. [PMID: 35960470 DOI: 10.1007/s11356-022-22470-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 08/06/2022] [Indexed: 05/27/2023]
Abstract
In the present study, via a 180-day field trial, the indicators of soil total cadmium, DTPA-Cd, organic matter, and plant cadmium extraction were tested after the application of chelate tetrasodium glutamate diacetate (GLDA) to investigate the potential of GLDA combined with Tagetes patula L. to remediate cadmium-contaminated soil. To do so, five GLDA treatments (e.g., 0, 292.5, 585, 1170, and 2340 kg hm-2) were practiced. For each treatment, the total GLDA was divided into two applications with 15-day intervals (0.25, 0.47, and 0.61 mg·kg-1) under T. patula plantation. Compared with the control, our results showed that GLDA application significantly increased the biomass of aerial parts of T. patula by 21.9% (p < 0.05). Likewise, Cd content in aboveground and underground parts of T. patula increased by 94.7% and 60.5%, respectively, compared with the control (p < 0.05). GLDA application caused significant increases in Cd accumulations in cell soluble fraction and cell wall by 290% and 123%, respectively (p < 0.05); soil pH and DTPA-Cd content increased with the increase of total application of GLDA. Co-application of GLDA (2340 kg hm-2) and T. patula reduced the total soil Cd content by 12.87% compared with the soil background. Altogether, our findings conclude on the efficacy of GLDA application for the remediation of Cd-contaminated farmlands under T. patula cultivation.
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Affiliation(s)
- Hongchuan Li
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, School of Resource and Environment, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Rui Jin
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, School of Resource and Environment, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Zhaowen Xu
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, School of Resource and Environment, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Hongxiang Hu
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, School of Resource and Environment, Anhui Agricultural University, Hefei, 230036, People's Republic of China.
| | - Yusef Kianpoor Kalkhajeh
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, School of Resource and Environment, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Yingying Zhao
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, School of Resource and Environment, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Linchuan Zhan
- Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, School of Resource and Environment, Anhui Agricultural University, Hefei, 230036, People's Republic of China
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Chemical forms of cadmium in soil and its distribution in French marigold sub-cells in response to chelator GLDA. Sci Rep 2022; 12:17577. [PMID: 36266400 PMCID: PMC9584924 DOI: 10.1038/s41598-022-20780-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/19/2022] [Indexed: 01/13/2023] Open
Abstract
The use of degradable chelating agents to facilitate phytoextraction is a promising low-cost method for the remediation of heavy metal-contaminated soils. However, there are few studies on how plants and soils respond to the chelating agents. In this study, the responses of French marigold (Tagetes patula L.) and soil cadmium (Cd) to the chelator tetrasodium glutamate (GLDA) was investigated in a 180 d field trial. Five GLDA treatments (0, 292.5, 585, 1170, and 2340 kg hm-2) were carried out in a Cd-contaminated soil (0.47 mg kg-1) under French marigold plantation. The results showed that the application of GLDA promoted the transformation of other forms of Cd in soil to exchangeable state, and the exchangeable Cd and Fe-Mn oxide bound state increased by 42.13% and 32.97% (p < 0.05), respectively. The cell wall Cd accumulations significantly increased 9.39% (p < 0.05) and the percentages of soluble fractions increased by 460.33% (p < 0.05). Furthermore, increases occurred in soil pH, as well as DOC and DTPA-Cd contents with increasing the total amount of GLDA. The composite application of GLDA (2340 kg hm-2) with French marigold reduced the total soil Cd content by 7.59% compared with the soil background. Altogether, results of this study suggested that the application of GLDA can effectively activate soil Cd and enhance the capability of French marigold for the remediation of Cd-contaminated soils.
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Schmidt SI, Hejzlar J, Kopáček J, Paule-Mercado MC, Porcal P, Vystavna Y, Lanta V. Forest damage and subsequent recovery alter the water composition in mountain lake catchments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 827:154293. [PMID: 35259388 DOI: 10.1016/j.scitotenv.2022.154293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/20/2022] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
Forest damage by insect infestation directly affects the trees themselves, but also indirectly affects water quality via soil processes. The changes in water composition may undergo different pathways depending on site-specific characteristics and forest components, especially the proportion of coniferous and deciduous trees. Here, we test whether changes in forest components and the intensity of disturbance can predict the chemical properties of water outflow from affected lake catchments. Information about forest regeneration (a phase dominated by deciduous trees) and the proportions of damaged and healthy coniferous trees and treeless areas were obtained from satellite data. The four study catchments of Prášilské, Laka, Plešné, and Čertovo lakes are geographically close and located in the same mountain range (Šumava Mts., Czech Republic) at similar altitude, but they differ in extents of forest disturbances and recoveries. The water quality measured at the lake catchment outflows differed, and better reflected the development of forest components and health than did meteorological (temperature and precipitation) or hydrological (discharge) variables. Several of the outflow properties (concentrations of inorganic aluminium, protons, potassium, calcium, magnesium, alkalinity, dissolved organic carbon (DOC), nitrate, and total phosphorus), responded catchment-specifically and with different delays to forest disturbance. The most pronounced differences occurred in DOC concentrations, which started to increase in the most disturbed Plešné and Laka catchments 7 and 6 years, respectively, after the peak in tree dieback, but did not increase significantly in the Prášilské catchment, which was disturbed several times during the last 3-4 decades. This study demonstrates an importance of extents of forest disturbances, the following changes in forest composition, and catchment-specific characteristics on water composition.
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Affiliation(s)
- Susanne I Schmidt
- Biology Centre CAS, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic.
| | - Josef Hejzlar
- Biology Centre CAS, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic
| | - Jiří Kopáček
- Biology Centre CAS, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic
| | | | - Petr Porcal
- Biology Centre CAS, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic
| | - Yuliya Vystavna
- Biology Centre CAS, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic
| | - Vojtěch Lanta
- Institute of Botany, Czech Academy of Sciences, Dukelská 135, 37901 Třeboň, Czech Republic
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Kaal J, Pérez-Rodríguez M, Biester H. Molecular Probing of DOM Indicates a Key Role of Spruce-Derived Lignin in the DOM and Metal Cycles of a Headwater Catchment: Can Spruce Forest Dieback Exacerbate Future Trends in the Browning of Central European Surface Waters? ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:2747-2759. [PMID: 35104105 DOI: 10.1021/acs.est.1c04719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Peatlands of the Northern Hemisphere and Central European coniferous forests experience significant environmental change. The resultant browning of surface waters, that is, elevated concentrations of dissolved organic matter (DOM) and metals, is of interest in the context of the global C cycle, peatland and forest management, and water treatment. In an attempt to identify the causes of this process in the Harz Mountains (Central Germany), we studied the spatiotemporal variations in DOM molecular composition (thermally assisted hydrolysis and methylation combined with GC-MS) and metal concentrations in headwater stream samples. We found strong relationships between DOM and metals and seasonal variations in the DOM quality and tentatively DOM-metal binding mode: during summer base flow, DOM and metal concentrations are low, and all elements other than the alkali and alkaline earth metals (Ca, Mg, Sr, K, and Na) are positively correlated to DOM, whereas during spring and autumn (high discharge), only metals with strong affinity for DOM (Fe, As, Cu, Cr, Pb, and Ti), but not weakly binding ones (Al, Cd, La, Mn, Ni, Zn, and Zr), are correlated to DOM, indicative of selectivity in DOM-metal interactions. The products of polyphenols are the key ingredients of the DOM-metal complexes. We argue the importance of spruce lignin-derived vanillic acid moieties, which are involved in weak (all seasons) and strong, multidentate and/or colloidal, binding (spring and autumn) of metals. Considering the ongoing spruce forest dieback and climate change acceleration, it is tempting to conclude that spruce necromass and forest soils may release vast amounts of lignin-derived DOM and associated metals to headwater streams. This would have significant implications for forest soil C stocks and the management of connected drinking water reservoirs.
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Affiliation(s)
- Joeri Kaal
- Institut für Geoökologie, Abteilung Umweltgeochemie, Technische Universität Braunschweig, Langer Kamp 19C, Braunschweig 38106, Germany
| | - Marta Pérez-Rodríguez
- Institut für Geoökologie, Abteilung Umweltgeochemie, Technische Universität Braunschweig, Langer Kamp 19C, Braunschweig 38106, Germany
| | - Harald Biester
- Institut für Geoökologie, Abteilung Umweltgeochemie, Technische Universität Braunschweig, Langer Kamp 19C, Braunschweig 38106, Germany
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Yang H, Graham NJD, Wang W, Liu M, Yu W. Evaluating and improving the reliability of the UV-persulfate method for the determination of TOC/DOC in surface waters. WATER RESEARCH 2021; 196:116918. [PMID: 33765497 DOI: 10.1016/j.watres.2021.116918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 02/04/2021] [Accepted: 02/07/2021] [Indexed: 06/12/2023]
Abstract
The UV-persulfate oxidation method is widely used for determining the total organic carbon concentration of aqueous samples (denoted for convenience as UVP-TOC). However, for some surface water samples, the measurement of TOC by this method can be unreliable, deviating significantly from the true carbon content. In this study, the performance of the UVP-TOC method has been investigated by comparing the results from the analysis of a variety of aqueous samples that included two kinds of surface water samples and related surface water model substances: bovine serum albumin (BSA), sodium alginate (SA), humic acid (HA), tannic acid (TA), benzoic acid (BA) and citric acid (CA), with those from a high-temperature combustion method (elemental analysis); the latter providing the true carbon content value. By comparing the above data, it was found that the UVP-TOC method significantly underestimated the TOC value of the surface water samples, and it was also found that the model components BSA (protein) and HA (humic substances, HS) had a substantial influence on the TOC underestimation, while the SA (polysaccharide), TA (complex organic molecule) and CA/BA (small molecules) had little effect. The results showed that the agglomeration within and between BSA and HA molecules was an important reason for the inaccurate UVP-TOC values of BSA and HA. A further limitation was that for BSA, surfactants (e.g. sodium dodecylbenzene sulfonate, SDBS) and other surfactant-like substances, foam was formed during the CO2 removal purging process by N2 that seriously interfered with the determination of TOC. The study provides new information and insight into the causes of inaccuracies in the UVP-TOC analysis of surface waters and possible approaches to improve the accuracy.
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Affiliation(s)
- Hankun Yang
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Nigel J D Graham
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Wenyu Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Separation Membrane and Membrane Processes, School of Environmental Science and Engineering, Tiangong University, Tianjin 300387, China
| | - Mengjie Liu
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Wenzheng Yu
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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Leonard LT, Mikkelson K, Hao Z, Brodie EL, Williams KH, Sharp JO. A comparison of lodgepole and spruce needle chemistry impacts on terrestrial biogeochemical processes during isolated decomposition. PeerJ 2020; 8:e9538. [PMID: 32742804 PMCID: PMC7369028 DOI: 10.7717/peerj.9538] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 06/23/2020] [Indexed: 12/01/2022] Open
Abstract
This study investigates the isolated decomposition of spruce and lodgepole conifer needles to enhance our understanding of how needle litter impacts near-surface terrestrial biogeochemical processes. Harvested needles were exported to a subalpine meadow to enable a discrete analysis of the decomposition processes over 2 years. Initial chemistry revealed the lodgepole needles to be less recalcitrant with a lower carbon to nitrogen (C:N) ratio. Total C and N fundamentally shifted within needle species over time with decreased C:N ratios for spruce and increased ratios for lodgepole. Differences in chemistry correlated with CO2 production and soil microbial communities. The most pronounced trends were associated with lodgepole needles in comparison to the spruce and needle-free controls. Increased organic carbon and nitrogen concentrations associated with needle presence in soil extractions further corroborate the results with clear biogeochemical signatures in association with needle chemistry. Interestingly, no clear differentiation was observed as a function of bark beetle impacted spruce needles vs those derived from healthy spruce trees despite initial differences in needle chemistry. These results reveal that the inherent chemistry associated with tree species has a greater impact on soil biogeochemical signatures during isolated needle decomposition. By extension, biogeochemical shifts associated with bark beetle infestation are likely driven more by changes such as the cessation of rhizospheric processes than by needle litter decomposition.
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Affiliation(s)
| | | | - Zhao Hao
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Eoin L Brodie
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Kenneth H Williams
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,Rocky Mountain Biological Laboratory, Crested Butte, CO, USA
| | - Jonathan O Sharp
- Colorado School of Mines, Golden, CO, USA.,Rocky Mountain Biological Laboratory, Crested Butte, CO, USA
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Kopáček J, Bače R, Hejzlar J, Kaňa J, Kučera T, Matějka K, Porcal P, Turek J. Changes in microclimate and hydrology in an unmanaged mountain forest catchment after insect-induced tree dieback. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 720:137518. [PMID: 32143039 DOI: 10.1016/j.scitotenv.2020.137518] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 02/06/2020] [Accepted: 02/22/2020] [Indexed: 06/10/2023]
Abstract
Hydrological and microclimatic changes after insect-induced tree dieback were evaluated in an unmanaged central European mountain (Plešné, PL) forest and compared to climate-related changes in a similar, but almost intact (Čertovo, CT) control forest during two decades. From 2004 to 2008, 93% of Norway spruce trees were killed by a bark beetle outbreak, and the entire PL area was left to subsequent natural development. We observed that (1) climate-related increases in daily mean air temperature (2 m above ground) were 1.6 and 0.5 °C on an annual and growing season basis, respectively, and an increase in daily mean soil temperature (5 cm below ground) was 0.9 °C during growing seasons at the CT control from 2004 to 2017; (2) daily mean soil and air temperatures increased by 0.7-1.2 °C on average more at the disturbed PL plots than in the healthy forest; (3) water input to soils increased by 20% but decreased by 17% at elevations of 1122 and 1334 m, respectively, due to decreased occult deposition to, and evaporation from, canopies after tree dieback; (4) soil moisture was 5% higher on average (but up to 17% higher in dry summer months) in the upper PL soil horizons for 5-6 years following the tree dieback; (5) run-off from the PL forest ~6% (~70 mm yr-1) increased relatively to the CT forest (but without extreme peak flows and erosion events) after tree dieback due to the ceased transpiration of dead trees and elevated water input to soils; and (6) relative air humidity was 4% lower on average at disturbed plots than beneath living trees. The rapid tree regeneration during the decade following tree dieback resulted in a complete recovery in soil moisture, a slow recovery of discharge and air humidity, but a still insignificant recovery in air and soil temperatures.
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Affiliation(s)
- Jiří Kopáček
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic.
| | - Radek Bače
- Czech University of Life Sciences, Faculty of Forestry and Wood Science, Prague, Czech Republic.
| | - Josef Hejzlar
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic.
| | - Jiří Kaňa
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic
| | - Tomáš Kučera
- University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic.
| | | | - Petr Porcal
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, České Budějovice, Czech Republic.
| | - Jan Turek
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic.
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