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1. Macrosystems revisited: challenges and successes in a new subdiscipline of ecology

Author:
Dodds, Walter K; Rose, Kevin C; Fei, Songlin; Chandra, Sudeep
Source:
Frontiers in ecology and the environment 2021 v.19 no.1 pp. 4-10
ISSN:
1540-9295
Subject:
biogeochemistry,   etc   ; biogeography; biosphere; community ecology; humans;     Show all 5 Subjects
Abstract:
... Macrosystems biology research has expanded and evolved over the past decade as the scientific community grapples with ecological issues at regional to continental scales relevant to human interactions within the biosphere. Macrosystems biology builds on established fields of study like population and community ecology, biogeography, and global biogeochemistry, and has the potential to develop into ...
DOI:
10.1002/fee.2286

2. Investigating soil carbon diversity by combining the MAXimum ENTropy principle with the Q model

Author:
Ågren, Göran I.
Source:
Biogeochemistry 2021 v.153 no.1 pp. 85-94
ISSN:
0168-2563
Subject:
biogeochemistry,   etc   ; fallow; mechanistic models; soil; soil organic carbon; variance;     Show all 6 Subjects
Abstract:
... Soil carbon diversity can be an important property for the stability of soil carbon. A problem is the lack of techniques for measuring this diversity. I suggest here the use of a combination of a general statistical principle, MAXimum ENTropy (MaxEnt), and a mechanistic model of organic matter decomposition, the Q model. The Q model provides the temporal development of the average carbon quality o ...
DOI:
10.1007/s10533-021-00771-1

3. Tracking Improvement in Simulated Marine Biogeochemistry Between CMIP5 and CMIP6

Author:
Séférian, Roland; Berthet, Sarah; Yool, Andrew; Palmiéri, Julien; Bopp, Laurent; Tagliabue, Alessandro; Kwiatkowski, Lester; Aumont, Olivier; Christian, James; Dunne, John; Gehlen, Marion; Ilyina, Tatiana; John, Jasmin G.; Li, Hongmei; Long, Matthew C.; Luo, Jessica Y.; Nakano, Hideyuki; Romanou, Anastasia; Schwinger, Jörg; Stock, Charles; Santana-Falcón, Yeray; Takano, Yohei; Tjiputra, Jerry; Tsujino, Hiroyuki; Watanabe, Michio; Wu, Tongwen; Wu, Fanghua; Yamamoto, Akitomo
Source:
Current climate change reports 2020 v.6 no.3 pp. 95-119
ISSN:
2198-6061
Subject:
biogeochemistry,   etc   ; climate; climate change; models;     Show all 4 Subjects
Abstract:
... PURPOSE OF REVIEW: The changes or updates in ocean biogeochemistry component have been mapped between CMIP5 and CMIP6 model versions, and an assessment made of how far these have led to improvements in the simulated mean state of marine biogeochemical models within the current generation of Earth system models (ESMs). RECENT FINDINGS: The representation of marine biogeochemistry has progressed wit ...
DOI:
10.1007/s40641-020-00160-0

4. Iron deposits turn blue shrimp gills to orange

Author:
Lemonnier, Hugues; Wabete, Nelly; Pham, Dominique; Lignot, Jean-Hervé; Barri, Kiam; Mermoud, Isabelle; Royer, Florence; Boulo, Viviane; Laugier, Thierry
Source:
Aquaculture 2021 v.540 pp. 736697
ISSN:
0044-8486
Subject:
biogeochemistry,   etc   ; Litopenaeus stylirostris; aquaculture; color; exoskeleton; histology; income; iron; sediments; shrimp; New Caledonia;     Show all 11 Subjects
Abstract:
... In the grow-out ponds of the blue shrimp (Litopenaeus stylirostris) farms of New Caledonia, animals with orange gills (OG) have been observed over the last ten years, with up to 70% of the shrimp in a given pond being affected. During the processing and marketing of the product, this coloring leads to reduced quality and selling prices, resulting in lower income for the producers concerned. Indivi ...
DOI:
10.1016/j.aquaculture.2021.736697

5. Acid sulfate soils on the west coast of Sri Lanka: A review

Author:
Vithana, Chamindra L.; Ulapane, Prashani A.K.; Chandrajith, Rohana; Sullivan, Leigh A.; Bundschuh, Jochen; Toppler, Nadia; Ward, Nicholas J.; Senaratne, Atula
Source:
Geoderma regional 2021 v.25 pp. e00382
ISSN:
2352-0094
Subject:
biogeochemistry,   etc   ; acid sulfate soils; acidity; coasts; landscapes; marshes; peat; peatlands; saltwater intrusion; sulfates; weather; Sri Lanka;     Show all 12 Subjects
Abstract:
... This article provides a general introduction to acid sulfate soil materials including those in Muthurajawela, a marsh of high ecological significance on the western coast of Sri Lanka. This peat bog is identified as one of the country's two acid sulfate soils landscapes. It covers ~3000 ha in area and contains a 3 to 7 m thick peat layer. Here we review the acid sulfate soils landscape of Muthuraj ...
DOI:
10.1016/j.geodrs.2021.e00382

6. Nitrogen biogeochemistry of water-agro-food systems: the example of the Seine land-to-sea continuum

Author:
Billen, Gilles; Garnier, Josette
Source:
Biogeochemistry 2021 v.154 no.2 pp. 307-321
ISSN:
0168-2563
Subject:
biogeochemistry,   etc   ; aquatic ecosystems; case studies; estuaries; food production; nitrogen; rivers; surface water; trade; waste management; watersheds;     Show all 11 Subjects
Abstract:
... As an illustration of the usefulness of the concept of water-agro-food systems, this paper describes the mechanisms behind the nitrogen cascade from agricultural soils to the coastal sea rivers through aquifers, riparian wetlands, rivers and streams and the estuary, for the case study of the Seine river watershed and its receiving coastal sea. It is stressed that the structure of the agro-food sys ...
DOI:
10.1007/s10533-020-00739-7

7. Origin and fate of dissolved organic matter in four shallow Baltic Sea estuaries

Author:
Voss, Maren; Asmala, Eero; Bartl, Ines; Carstensen, Jacob; Conley, Daniel J.; Dippner, Joachim W.; Humborg, Christoph; Lukkari, Kaarina; Petkuviene, Jolita; Reader, Heather; Stedmon, Colin; Vybernaite-Lubiene, Irma; Wannicke, Nicola; Zilius, Mindaugas
Source:
Biogeochemistry 2021 v.154 no.2 pp. 385-403
ISSN:
0168-2563
Subject:
biogeochemistry,   etc   ; carbon; dissolved organic matter; freshwater; land use; nitrogen; phosphorus; salinity; spring; watersheds; Baltic Sea;     Show all 11 Subjects
Abstract:
... Coastal waters have strong gradients in dissolved organic matter (DOM) quantity and characteristics, originating from terrestrial inputs and autochthonous production. Enclosed seas with high freshwater input therefore experience high DOM concentrations and gradients from freshwater sources to more saline waters. The brackish Baltic Sea experiences such salinity gradients from east to west and from ...
DOI:
10.1007/s10533-020-00703-5

8. Role of external inputs of nutrients to aquatic ecosystems in determining prevalence of nitrogen vs. phosphorus limitation of net primary productivity

Author:
Howarth, R. W.; Chan, F.; Swaney, D. P.; Marino, R. M.; Hayn, M.
Source:
Biogeochemistry 2021 v.154 no.2 pp. 293-306
ISSN:
0168-2563
Subject:
biogeochemistry,   etc   ; continental shelf; lakes; net primary productivity; nitrogen; phosphorus; phytoplankton; watersheds;     Show all 8 Subjects
Abstract:
... Whether net primary productivity in an aquatic ecosystem is limited by nitrogen (N), limited by phosphorus (P), or co-limited by N & P is determined by the relative supply of N and P to phytoplankton compared to their elemental requirements for primary production, often characterized by the “Redfield” ratio. The supply of these essential nutrients is affected by both external inputs and biogeochem ...
DOI:
10.1007/s10533-021-00765-z

9. The role of internal feedbacks in shifting deep lake mixing regimes under a warming climate

Author:
Mesman, Jorrit P.; Stelzer, Julio A. A.; Dakos, Vasilis; Goyette, Stéphane; Jones, Ian D.; Kasparian, Jérôme; McGinnis, Daniel F.; Ibelings, Bas W.
Source:
Freshwater biology 2021 v.66 no.6 pp. 1021-1035
ISSN:
0046-5070
Subject:
biogeochemistry,   etc   ; climate; ecosystems; hypoxia; ice cover; insulating materials; lakes; limnology; memory; morphometry; phytoplankton; snow; temperature; winter;     Show all 14 Subjects
Abstract:
... Climate warming is causing changes in the physics of deep lakes, such as longer summer stratification, increased water column stability, reduced ice cover, and a shallower depth of winter overturns. An ultimate consequence of warming would be a transition to a different mixing regime. Here we investigate the role of physical, chemical, and biological feedback mechanisms that unfold during a shift ...
DOI:
10.1111/fwb.13704

10. Periphyton enhances arsenic release and methylation at the soil-water interface of paddy soils

Author:
Guo, Ting; Gustave, Williamson; Lu, Haiying; He, Yan; Tang, Xianjin; Buchwalter, David B.; Xu, Jianming
Source:
Journal of hazardous materials 2021 v.409 pp. 124946
ISSN:
0304-3894
Subject:
biogeochemistry,   etc   ; Kineosporia; arsenic; biotransformation; dissolved organic carbon; methylation; paddies; paddy soils; periphyton; phosphates; rice; soil water;     Show all 12 Subjects
Abstract:
... Periphyton is ubiquitous in rice paddy fields, however its role in paddy soil arsenic (As) biogeochemistry remains unexplored. In this study, microcosm incubations and extensive field sampling were used to better understand the roles of periphyton on As mobility and transformation at the soil-water interface. Microcosm incubations revealed that periphyton on the paddy soil surface enhanced As rele ...
DOI:
10.1016/j.jhazmat.2020.124946

11. Effect of soil amendments on trace element-mediated oxidative stress in plants: Meta-analysis and mechanistic interpretations

Author:
Shahid, Muhammad
Source:
Journal of hazardous materials 2021 v.407 pp. 124881
ISSN:
0304-3894
Subject:
biogeochemistry,   etc   ; ecotoxicology; lipid peroxidation; meta-analysis; oxidative stress; plant response; remediation; soil; toxicity; trace elements;     Show all 10 Subjects
Abstract:
... During the last two decades, the use of soil amendments has gained high attention due to their role in governing trace element biogeochemistry in the soil. Majority of the studies dealing with soil amendments focused on the soil-plant transfer of trace elements, their compartmentation inside the plants and associated toxic effects. However, there is comparatively limited data regarding the effects ...
DOI:
10.1016/j.jhazmat.2020.124881

12. Evidence linking calcium to increased organo-mineral association in soils

Author:
Rowley, Mike C.; Grand, Stephanie; Spangenberg, Jorge E.; Verrecchia, Eric P.
Source:
Biogeochemistry 2021 v.153 no.3 pp. 223-241
ISSN:
0168-2563
Subject:
biogeochemistry,   etc   ; X-ray photoelectron spectroscopy; calcium; fractionation; soil; soil organic carbon; sonication; stable isotopes; thermal stability;     Show all 9 Subjects
Abstract:
... Geochemical indicators are emerging as important predictors of soil organic carbon (SOC) dynamics, but evidence concerning the role of calcium (Ca) is scarce. This study investigates the role of Ca prevalence in SOC accumulation by comparing otherwise similar sites with (CaCO₃-bearing) or without carbonates (CaCO₃-free). We measured the SOC content and indicators of organic matter quality (C stabl ...
DOI:
10.1007/s10533-021-00779-7

13. Pulse labelling of deep soil layers in forest with 13CH4: testing a new method for tracing methane in the upper horizons, understorey vegetation and tree stems using laser-based spectrometry

Author:
Plain, C.; Epron, D.
Source:
Biogeochemistry 2021 v.153 no.2 pp. 215-222
ISSN:
0168-2563
Subject:
biogeochemistry,   etc   ; forest soils; methane; soil depth; soil water content; spectroscopy; trees; understory; upland forests;     Show all 9 Subjects
Abstract:
... Methane emissions from plants in wetlands are mainly due to internal transport, from the anoxic soil layers where methane is produced, to the atmosphere. This pathway has not yet been clearly demonstrated for upland forest vegetation, where methane can be produced in deep soil layers. We developed a new method to trace methane transfer from the deep soil. We conducted a ¹³CH₄ pulse labelling at 40 ...
DOI:
10.1007/s10533-021-00775-x

14. Underlying riparian lithology controls redox dynamics during stage-driven mixing

Author:
Wallace, Corey D.; Soltanian, Mohamad Reza
Source:
Journal of hydrology 2021 v.595 pp. 126035
ISSN:
0022-1694
Subject:
biogeochemistry,   etc   ; aquifers; hyporheic zone; lithology; organic matter; redox potential; river water; sediments; storms; temporal variation;     Show all 10 Subjects
Abstract:
... The interactions between surface water-groundwater (hyporheic) exchange and sediment lithology influence oxidation–reduction (redox) conditions near river-aquifer interfaces. Redox dynamics have implications for subsurface nutrient transformations, but are difficult to assess spatially and temporally using traditional geochemical observations. This study applied continuous, three-dimensional monit ...
DOI:
10.1016/j.jhydrol.2021.126035

15. Watershed Alnus cover alters N:P stoichiometry and intensifies P limitation in subarctic streams

Author:
Devotta, Denise A.; Fraterrigo, Jennifer M.; Walsh, Patrick B.; Lowe, Stacey; Sewell, Daniel K.; Schindler, Daniel E.; Hu, Feng Sheng
Source:
Biogeochemistry 2021 v.153 no.2 pp. 155-176
ISSN:
0168-2563
Subject:
biogeochemistry,   etc   ; Alnus; climatic factors; hydrology; landscapes; nitrogen; phosphorus; spring; stoichiometry; streams; summer; vegetation; watersheds; Alaska;     Show all 14 Subjects
Abstract:
... In many watersheds, nitrogen (N)-fixing alder (Alnus spp.) provides key nutrient subsidies to terrestrial and aquatic ecosystems. The importance of these subsidies may increase as alder cover expands under climate warming at high latitudes. We assessed how landscape features and meteorological conditions affect aquatic N and phosphorus (P) availability and stoichiometry in 26 streams across natura ...
DOI:
10.1007/s10533-021-00776-w

16. Mercury biogeochemistry over the Tibetan Plateau: An overview

Author:
Sun, Ruiyang; Sun, Guangyi; Kwon, Sae Yun; Feng, Xinbin; Kang, Shichang; Zhang, Qianggong; Huang, Jie; Yin, Runsheng
Source:
Critical reviews in environmental science and technology 2021 v.51 no.6 pp. 577-602
ISSN:
1547-6537
Subject:
biogeochemistry,   etc   ; bioaccumulation; climate; cold; glaciers; mercury; monsoon season; pollution; soil; technology; vegetation; China;     Show all 12 Subjects
Abstract:
... Since the beginning of the 21st century, our knowledge of the sources and fate of Hg over the Tibetan Plateau (TP), the “Roof of the World,” has been greatly enhanced with growing literature. Here, we reviewed the available literature to obtain a comprehensive understanding of Hg biogeochemistry over the TP. The biogeochemical Hg cycling is characterized by the following features: (1) There are ex ...
DOI:
10.1080/10643389.2020.1733894

17. Long-term litter type treatments alter soil carbon composition but not microbial carbon utilization in a mixed pine-oak forest

Author:
Guo, Xiaowei; Luo, Zhongkui; Sun, Osbert Jianxin
Source:
Biogeochemistry 2021 v.152 no.2-3 pp. 327-343
ISSN:
0168-2563
Subject:
biogeochemistry,   etc   ; forest litter; forests; leaves; microbial carbon; mineral soils; nitrogen; soil organic carbon; temperate zones;     Show all 9 Subjects
Abstract:
... Changes in litter and nutrient inputs into soil could have significant consequences on forest carbon (C) dynamics via controls on the structure and microbial utilization of soil organic C (SOC). In this study, we assessed changes in physical fractions (250–2000 μm, 53–250 μm, and < 53 μm soil aggregates) and chemical fractions (labile, intermediate and recalcitrant pools) of SOC in the top 20 cm m ...
DOI:
10.1007/s10533-021-00757-z

18. Measuring nitrogen fixation by the acetylene reduction assay (ARA): is 3 the magic ratio?

Author:
Soper, Fiona M.; Simon, Camille; Jauss, Verena
Source:
Biogeochemistry 2021 v.152 no.2-3 pp. 345-351
ISSN:
0168-2563
Subject:
biogeochemistry,   etc   ; acetylene; acetylene reduction; biological soil crusts; ethylene; lichens; nitrogen; nitrogen fixation; nitrogenase; wood;     Show all 10 Subjects
Abstract:
... Despite some well-documented drawbacks, the acetylene reduction assay (ARA) remains one of the most widespread methods for measuring biological nitrogen (N₂) fixation (BNF) in symbiotic and free-living niches due to its low cost, simplicity, and high throughput potential. Because ARA measures a proxy reaction (the reduction of acetylene to ethylene by the nitrogenase enzyme), a conversion ratio (‘ ...
DOI:
10.1007/s10533-021-00761-3

19. The biogeochemistry of copper metallophytes in the Roseby Corridor (North-West Queensland, Australia)

Author:
Tang, Roger H.; Erskine, Peter D.; Lilly, Richard; van der Ent, Antony
Source:
Chemoecology 2021 v.31 no.1 pp. 19-30
ISSN:
0937-7409
Subject:
biogeochemistry,   etc   ; ; Digitaria; Tephrosia; chlorosis; copper; death; hyperaccumulators; leaves; mineralization; rhizosphere; soil; Queensland;     Show all 13 Subjects
Abstract:
... The ability of Australian native metallophytes to tolerate extreme metal concentrations in the soil and other difficult edaphic conditions is still not well understood. Copper is an essential micronutrient for plants to survive, but at high concentrations (> 20 µg g⁻¹) in plant tissues, it can cause foliar chlorosis, stunted growth, and ultimately plant death. The Roseby Corridor in Central Queens ...
DOI:
10.1007/s00049-020-00325-1

20. Ferrous iron enhances arsenic sorption and oxidation by non-stoichiometric magnetite and maghemite

Author:
Gubler, Reto; ThomasArrigo, Laurel K.
Source:
Journal of hazardous materials 2021 v.402 pp. 123425
ISSN:
0304-3894
Subject:
biogeochemistry,   etc   ; X-ray absorption spectroscopy; arsenic; crystallization; iron; maghemite; magnetite; oxidation; pH; risk; sorption; stoichiometry; toxicity;     Show all 13 Subjects
Abstract:
... Arsenic-contaminated waters affect millions of people on a daily basis. Because the toxicity of As is dependent on the redox state, understanding As biogeochemistry, particularly in reducing environments, is critical to addressing the environmental risk that As poses. Sorption of As to Fe(III)-(oxyhydr)oxides is an important mechanism for As removal from solution under anoxic conditions. However, ...
DOI:
10.1016/j.jhazmat.2020.123425