Ectomycorrhizal access to organic nitrogen mediates CO2 fertilization response in a dominant temperate tree

AbstractPlant–mycorrhizal interactions mediate plant nitrogen (N) limitation and can inform model projections of the duration and strength of the effect of increasing CO2 on plant growth. We present dendrochronological evidence of a positive, but context-dependent fertilization response of Quercus rubra L. to increasing ambient CO2 (iCO2) along a natural soil nutrient gradient in a mature temperate forest. We investigated this heterogeneous response by linking metagenomic measurements of ectomycorrhizal (ECM) fungal N-foraging traits and dendrochronological models of plant uptake of inorganic N and N bound in soil organic matter (N-SOM). N-SOM putatively enhanced tree growth under conditions of low inorganic N availability, soil conditions where ECM fungal communities possessed greater genomic potential to decay SOM and obtain N-SOM. These trees were fertilized by 38 years of iCO2. In contrast, trees occupying inorganic N rich soils hosted ECM fungal communities with reduced SOM decay capacity and exhibited neutral growth responses to iCO2. This study elucidates how the distribution of N-foraging traits among ECM fungal communities govern tree access to N-SOM and subsequent growth responses to iCO2.

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Biogeochemical Effects of a Forest Understory Plant Invasion Depend More On Dissimilar Nutrient Economies Than Invader Biomass

10.21203/rs.3.rs-941156/v1 ◽

2021 ◽

Author(s):

Laura Y Podzikowski ◽

Marissa Lee ◽

Catherine Fahey ◽

Justin Wright ◽

S. Luke Flory ◽

...

Keyword(s):

Native Species ◽

Soil Nutrient ◽

Arbuscular Mycorrhizal ◽

Nutrient Acquisition ◽

Forest Understory ◽

Soil Conditions ◽

N Availability ◽

Invasive Grass ◽

Acquisition Strategies ◽

Nutrient Economy

Abstract There is an increasing need to better understand how and why invasion impacts differ across heterogeneous landscapes. One hypothesis predicts invader impacts are greatest where the invader is most abundant (the mass ratio hypothesis; MRH). Alternatively, invader impacts may be greatest in communities where the nutrient acquisition strategies of the invader are most dissimilar from those of native species (the nutrient economy dissimilarity hypothesis; NEDH). We tested whether the effects of an invasive grass, Microstegium vimineum, on soil biogeochemistry were best explained by MRH, NEDH, or both. At three locations (Indiana, North Carolina, and Georgia), invaded and reference plots were established across a nutrient economy gradient. Plots varied in the relative abundance of arbuscular mycorrhizal (AM) vs. ectomycorrhizal (ECM) associated overstory trees, reflecting gradients in biotic nutrient acquisition strategies and edaphic factors. At two locations, we found NEDH predicted invader effects on soil conditions. The net effect of M. vimineum homogenized soil properties across the nutrient economy gradient towards conditions consistent with AM-dominated stands; as such, the nutrient economy gradients observed in uninvaded plots were mostly absent in invaded plots. At one location with high N availability and intermediate acidity, both ECM-dominance (NEDH) and invader abundance (MRH) predicted differences in soil moisture, pH, and nitrification rates. Collectively, these results suggest the biogeochemical consequences of M. vimineum depend, in part, on pre-invasion soil nutrient economies. Where pre-invasion conditions are known, we provide a scalable and predictive approach to determine where impacts on biogeochemical cycling of C and N may be greatest.

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Root foraging of birch and larch in heterogeneous soil nutrient patches under water deficit

PLoS ONE ◽

10.1371/journal.pone.0255848 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0255848

Author(s):

Long Tan ◽

Ruifeng Fan ◽

Huifeng Sun ◽

Shenglei Guo

Keyword(s):

Temperate Forest ◽

Soil Nutrient ◽

Soil Conditions ◽

Drought Treatment ◽

Root Foraging ◽

Nutrient Patches ◽

N Concentration ◽

N Utilization ◽

Split Root System ◽

Heterogeneous Soil

Water and nutrient are two critical factors that limit plant growth to spatial-temporal extents. Tree root foraging behavior has not received adequate attention in heterogeneous soil environments in temperate forest under drought pressure. In this study, birch (Betula platyphylla) and larch (Larix olgensis) seedlings were raised in pots in a split-root system with artificially heterogeneous soil environments to study the root foraging response to drought. Potted space was split into two halves where substrates were mixed with fertilizers in 67.5 mg nitrogen (N) plant-1 (N-P2O5-K2O, 14-13-13) to both halves as to create a homogeneous condition. Otherwise, a rate of 135 mg N plant-1 of fertilizers was delivered to a random half to create a heterogeneous condition. Half of seedlings were fully sub-irrigated every three days with the other half received the drought treatment by being watered every six days. Both birch and larch seedlings showed greater net shoot growth and biomass increment in well-watered condition, while root morphology was promoted by drought. Both species placed more fine roots with higher root N concentration in nutrient-enriched patches. In the heterogeneous pattern, birch showed a higher foraging precision assessed by biomass and greater foraging plasticity assessed in morphology and physiology. In contrast, larch seedlings had higher root N concentration in the well-watered condition. Neither species showed a significant response of N utilization to the heterogeneous pattern, but both used more N when water supply was improved. Overall, birch is better at acclimating to heterogeneous soil conditions, but its ability to seize N was lower than larch when drought was alleviated.

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Effects of elevated atmospheric carbon dioxide, soil nutrients and water conditions on photosynthetic and growth responses of Alnus hirsuta

Functional Plant Biology ◽

10.1071/fp11024 ◽

2011 ◽

Vol 38 (9) ◽

pp. 702 ◽

Cited By ~ 12

Author(s):

Hiroyuki Tobita ◽

Akira Uemura ◽

Mitsutoshi Kitao ◽

Satoshi Kitaoka ◽

Yutaka Maruyama ◽

...

Keyword(s):

Elevated Co2 ◽

Biomass Allocation ◽

Environmental Changes ◽

Soil Conditions ◽

Soil Drought ◽

N Availability ◽

P Availability ◽

Growth Responses ◽

Alnus Hirsuta ◽

Photosynthetic Properties

The objective of this paper is to clarify the effects of multiple environmental conditions, elevated atmospheric CO2 concentration ([CO2]) and soil conditions on the physiological and morphological properties of Alnus hirsuta Turcz., an N2-fixing species, to predict its responses to environmental changes. We examined the responses of photosynthetic properties, leaf characteristics, biomass and N allocation of A. hirsuta to elevated [CO2], soil N and phosphorus availability, and soil drought by using the results of two experiments. The effects of P availability were more marked than those of N availability and soil drought. The photosynthetic responses of A. hirsuta to elevated [CO2] under high P were considered to be ‘photosynthetic acclimation’, while A. hirsuta presented the obvious ‘photosynthetic downregulation’ to elevated [CO2] under low P. Soil P availability affected the growth responses to elevated [CO2] through effects on these photosynthetic properties and biomass allocation. Though elevated [CO2] caused no marked change in the allometric relationships in biomass, with some exceptions, the responses of N allocation among tissue to elevated [CO2] differed from those of biomass allocation. These results suggest that it is necessary to evaluate N mass allocation as well as biomass when we consider the N2-fixing ability of Alnus under elevated [CO2].

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Impact of tillage and landscape position on nitrogen availability and yield of spring wheat in the Brown soil zone in southwestern Saskatchewan

Canadian Journal of Soil Science ◽

10.4141/s97-065 ◽

1998 ◽

Vol 78 (3) ◽

pp. 563-572 ◽

Cited By ~ 36

Author(s):

V. Jowkin ◽

J. J. Schoenau

Keyword(s):

Spring Wheat ◽

Nitrogen Availability ◽

N Uptake ◽

Wheat Crop ◽

N Availability ◽

Inorganic N ◽

Brown Soil ◽

Soil Zone ◽

No Till ◽

Crop N Uptake

Nitrogen availability to a spring wheat crop was examined in the cropping season in a side-by-side comparison of no-till (first year) and tillage fallow in an undulating farm field in the Brown soil zone in southwestern Saskatchewan. Thirty different sampling points along a grid in each tillage landscape were randomly selected, representing 10 each of shoulder, footslope and level landscape positions. Nitrogen availability was studied i) by profile inorganic N content ii) by crop N uptake and yield of spring wheat (Triticum aestivum L.) and iii) by 15N tracer technique and in situ burial of anion exchange resin membranes (AEM).Pre-seeding available moisture content of the surface soil samples was significantly higher under no-till compared with tillage fallow. However, no significant differences in pre-seeding profile total inorganic N, crop N uptake and yield were observed between the treatments. At the landform scale, shoulder positions of the respective tillage systems had lower profile inorganic N, crop N uptake and yield compared with other slope positions. Soil N supply power, as determined by 15N tracer and AEM techniques, was not significantly different between the tillage treatments, indicating that N availability is not likely to be greatly affected in initial years by switching to no-till fallow in these soils under normal moisture conditions. Key words: Summerfallow, landscape, nitrogen, wheat

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Insights into mechanisms governing forest carbon response to nitrogen deposition: a model–data comparison using observed responses to nitrogen addition

Biogeosciences ◽

10.5194/bg-10-3869-2013 ◽

2013 ◽

Vol 10 (6) ◽

pp. 3869-3887 ◽

Cited By ~ 46

Author(s):

R. Q. Thomas ◽

G. B. Bonan ◽

C. L. Goodale

Keyword(s):

Plant Uptake ◽

Temperate Forest ◽

Growth Response ◽

N Fertilization ◽

N Deposition ◽

Forest Carbon ◽

Biogeochemical Model ◽

N Fixation ◽

N Availability ◽

Fertilization Experiments

Abstract. In many forest ecosystems, nitrogen (N) deposition enhances plant uptake of carbon dioxide, thus reducing climate warming from fossil fuel emissions. Therefore, accurately modeling how forest carbon (C) sequestration responds to N deposition is critical for understanding how future changes in N availability will influence climate. Here, we use observations of forest C response to N inputs along N deposition gradients and at five temperate forest sites with fertilization experiments to test and improve a global biogeochemical model (CLM-CN 4.0). We show that the CLM-CN plant C growth response to N deposition was smaller than observed and the modeled response to N fertilization was larger than observed. A set of modifications to the CLM-CN improved the correspondence between model predictions and observational data (1) by increasing the aboveground C storage in response to historical N deposition (1850–2004) from 14 to 34 kg C per additional kg N added through deposition and (2) by decreasing the aboveground net primary productivity response to N fertilization experiments from 91 to 57 g C m−2 yr−1. Modeled growth response to N deposition was most sensitive to altering the processes that control plant N uptake and the pathways of N loss. The response to N deposition also increased with a more closed N cycle (reduced N fixation and N gas loss) and decreased when prioritizing microbial over plant uptake of soil inorganic N. The net effect of all the modifications to the CLM-CN resulted in greater retention of N deposition and a greater role of synergy between N deposition and rising atmospheric CO2 as a mechanism governing increases in temperate forest primary production over the 20th century. Overall, testing models with both the response to gradual increases in N inputs over decades (N deposition) and N pulse additions of N over multiple years (N fertilization) allows for greater understanding of the mechanisms governing C–N coupling.

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Logging impacts on the biogeochemistry of boreal forest soils and nutrient export to aquatic systems: A review

Environmental Reviews ◽

10.1139/a08-006 ◽

2008 ◽

Vol 16 (NA) ◽

pp. 157-179 ◽

Cited By ~ 184

Author(s):

David P. Kreutzweiser ◽

Paul W. Hazlett ◽

John M. Gunn

Keyword(s):

Boreal Forest ◽

Nutrient Availability ◽

Soil Nutrient ◽

Soil Conditions ◽

Soil Nutrient Availability ◽

Clear Cutting ◽

Partial Harvest ◽

Forest Watersheds ◽

Logging Impacts ◽

Receiving Waters

Logging disturbances in boreal forest watersheds can alter biogeochemical processes in soils by changing forest composition, plant uptake rates, soil conditions, moisture and temperature regimes, soil microbial activity, and water fluxes. In general, these changes have often led to short-term increases in soil nutrient availability followed by increased mobility and losses by leaching to receiving waters. Among the studies we reviewed, dissolved organic carbon (DOC) exports usually increased after logging, and nitrogen (N) mineralization and nitrification often increased with resulting increased N availability and exports to receiving waters. Similar processes and responses occurred for phosphorus (P), but to a lesser extent than for N. In most cases, base cations were released and exported to receiving waters after logging. Several studies demonstrated that stem-only or partial-harvest logging reduced the impacts on nutrient release and exports in comparison to whole-tree clear-cutting. Despite these logging-induced increases in soil nutrient availability and movement to receiving waters, most studies reported little or no change in soil chemical properties. However, responses to logging were highly variable and often site specific. The likelihood, extent and magnitude of logging impacts on soil nutrient cycling and exports in boreal forest watersheds will be dependent on soil types, stand and site conditions, hydrological connectivity, post-logging weather patterns, and type and timing of harvest activities. Additionally, logging impacts can interact with, and be confounded by, atmospheric pollutant deposition and climate change. Further watershed-level empirical studies and modeling efforts are required to elucidate these interactions, to improve predictive capabilities, and to advance forest management guidelines for sustaining forest soil productivity and limiting nutrient exports.

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Vineyard ecosystems are structured and distinguished by fungal communities impacting the flavour and quality of wine

10.1101/2019.12.27.881656 ◽

2019 ◽

Author(s):

Di Liu ◽

Qinglin Chen ◽

Pangzhen Zhang ◽

Deli Chen ◽

Kate S. Howell

Keyword(s):

Regional Distribution ◽

Distribution Patterns ◽

Wine Fermentation ◽

Fungal Communities ◽

Soil Microbiome ◽

Soil Conditions ◽

Wine Aroma ◽

Wine Production ◽

Microbial Distribution

AbstractThe flavours of foods and beverages are formed by the agricultural environment where the plants are grown. In the case of wine, the location and environmental features of the vineyard site imprint the wine with distinctive aromas and flavours. Microbial growth and metabolism play an integral role in wine production from the vineyard to the winery, by influencing grapevine health, wine fermentation, and the flavour, aroma and quality of finished wines. The mechanism by which microbial distribution patterns drive wine metabolites is unclear and while flavour has been correlated with bacterial composition for red wines, bacterial activity provides a minor biochemical conversion in wine fermentation. Here, we collected samples across six distinct winegrowing areas in southern Australia to investigate regional distribution patterns of both fungi and bacteria and how this corresponds with wine aroma compounds. Results show that soil and must microbiota distinguish winegrowing regions and are related to wine chemical profiles. We found a strong relationship between microbial and wine metabolic profiles, and this relationship was maintained despite differing abiotic drivers (soil properties and weather/ climatic measures). Notably, fungal communities played the principal role in shaping wine aroma profiles and regional distinctiveness. We found that the soil microbiome is a potential source of grape- and must-associated fungi, and therefore the weather and soil conditions could influence the wine characteristics via shaping the soil fungal community compositions. Our study describes a comprehensive scenario of wine microbial biogeography in which microbial diversity responds to surrounding environments and ultimately sculpts wine aromatic characteristics. These findings provide perspectives for thoughtful human practices to optimise food and beverage flavour and composition through understanding of fungal activity and abundance.

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Ground-exploring routes of the Volyn region

Visnyk of the Lviv University. Series Geography ◽

10.30970/vgg.2017.51.8857 ◽

2017 ◽

pp. 179-192

Author(s):

Pavlo Kucher ◽

Ivan Voloshyn ◽

Andrii Kukhtiy

Keyword(s):

Chemical Properties ◽

Soil Science ◽

Soil Conditions ◽

Natural Soil ◽

Peat Bogs ◽

Forest Steppe ◽

Podzolic Soils ◽

Typical Chernozems ◽

Soil Forming Processes ◽

Soil Distribution

The article highlights the features of conducting soil excursion cognitive routes. We have proposed a comprehensive cognitive route for tourists of various degrees of educational level: schoolchildren and students of natural sciences. For each type of tourists, according to their wishes, information on natural features, soil cover and other excursion facilities are provided. Complex excursions are offered to attract more tourists. It is proposed to include in excursion routes: monuments and memorable places, architectural, archaeological, historical, sacral, museum and other valuable tourist objects. The excursion route in the Volyn region consists of eight soil study areas, where information is provided on the natural soil conditions, the most common types of soils, including gray forest soils, typical chernozems, sod-podzolic soils, peat soils and peat bogs. Two soils study areas are located on the forest-steppe area, where information on the main types of soils, their granulometric composition, and chemical properties are highlighted. The third-eighth field is laid within Volyn Polissya. Based on the study of the features of soil distribution, a soil-cognitive tourism route within the limits of the Forest-steppe and Volyn Polissya has been developed. The tour consists of information on the natural features of this territory, which testify to the conditions of the soil-forming processes, depending on the characteristics of natural conditions. During the soil study route, the peculiarities of distribution of the main types of soils and soil-forming rocks are highlighted. A table is prepared, in which a brief description of all types of soils found on the route and interesting tourist objects is located. Key words: soil, soil science cognitive field, tourist object, soil science route.

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Influence of Cover Crop, Tillage, and Crop Rotation Management on Soil Nutrients

Agriculture ◽

10.3390/agriculture10060225 ◽

2020 ◽

Vol 10 (6) ◽

pp. 225 ◽

Cited By ~ 2

Author(s):

Samuel I. Haruna ◽

Nsalambi V. Nkongolo

Keyword(s):

Crop Rotation ◽

Soil Nutrients ◽

Cover Crop ◽

Crop Production ◽

Production Systems ◽

Soil Nutrient ◽

Conventional Tillage ◽

N Availability ◽

P Availability ◽

Long Term Effects

Cover cropping, tillage and crop rotation management can influence soil nutrient availability and crop yield through changes in soil physical, chemical and biological processes. The objective of this study was to evaluate the influence of three years of cover crop, tillage, and crop rotation on selected soil nutrients. Twenty-four plots each of corn (Zea mays) and soybean (Glycine max) were established on a 4.05 ha field and arranged in a three-factor factorial design. The three factors (treatments) were two methods of tillage (no-tillage (NT) vs. moldboard plow [conventional] tillage (CT)), two types of cover crop (no cover crop (NC) vs. cover crop (CC)) and four typess of rotation (continuous corn, continuous soybean, corn/soybean and soybean/corn). Soil samples were taken each year at four different depths in each plot; 0–10 cm, 10–20 cm, 20–40 cm and 40–60 cm, and analyzed for soil nutrients: calcium (Ca), magnesium (Mg), nitrogen (NO3 and NH4), potassium (K), phosphorus (P), sulfur (S), sodium (Na), iron (Fe), manganese (Mn) and copper (Cu). The results in the first year showed that CT increased NO3-N availability by 40% compared with NT. In the second year, NH4-N was 8% lower under CC compared with NC management. In the third year, P was 12% greater under CC management compared with NC management. Thus, CC can enhance crop production systems by increasing P availability and scavenging excess NH4-N from the soil, but longer-term studies are needed to evaluate long-term effects.

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