Restoring oak forests through direct seeding or planting: Protocol for a continental-scale experiment

The choice of revegetating via direct seeding or planting nursery-grown seedlings influences the potential stresses suffered by seedlings such as herbivory and drought. The outcome of the balance between both revegetation methods may ultimately depend on how species identity and traits such as seed and seedling size interact with environmental conditions. To test this, we will conduct a continental-scale experiment consisting of one mini-experiment replicated by multiple participants across Europe. Each participant will establish a site with seeded and planted individuals of one or more native, locally growing oak (Quercus) species; the selection of this genus aims to favour continental-scale participation and to allow testing the response of a widely distributed genus of broad ecological and economic relevance. At each site, participants will follow the present protocol for seed collection, seeding in the field, nursery cultivation, outplanting, protection against herbivores, site maintenance, and measurement of seedling performance and environmental variables. Each measurement on each species at each site will produce one effect size; the data will be analysed through mixed-effects meta-analysis. With this approach we will assess the main effect of revegetation method, species, plant functional traits, and the potential effect of site-specific effect moderators. Overall, we will provide a continental-scale estimate on the seeding vs. planting dilemma and analyse to what extent the differences in environmental conditions across sites, seed size, functional traits, and the phylogenetic relatedness of species can account for the differences in the effect of revegetation method on seedling performance across study sites and species.

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Regional environmental controllers influence continental scale soil carbon stocks and future carbon dynamics

Scientific Reports ◽

10.1038/s41598-021-85992-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Daniel Ruiz Potma Gonçalves ◽

Umakant Mishra ◽

Skye Wills ◽

Sagar Gautam

Keyword(s):

Environmental Factors ◽

Land Cover ◽

Environmental Conditions ◽

Climate Feedback ◽

Soil Types ◽

Climatic Data ◽

Earth System ◽

Land Cover Types ◽

Continental Scale ◽

Soc Stocks

AbstractUnderstanding the influence of environmental factors on soil organic carbon (SOC) is critical for quantifying and reducing the uncertainty in carbon climate feedback projections under changing environmental conditions. We explored the effect of climatic variables, land cover types, topographic attributes, soil types and bedrock geology on SOC stocks of top 1 m depth across conterminous United States (US) ecoregions. Using 4559 soil profile observations and high-resolution data of environmental factors, we identified dominant environmental controllers of SOC stocks in 21 US ecoregions using geographically weighted regression. We used projected climatic data of SSP126 and SSP585 scenarios from GFDL-ESM 4 Earth System Model of Coupled Model Intercomparison Project phase 6 to predict SOC stock changes across continental US between 2030 and 2100. Both baseline and predicted changes in SOC stocks were compared with SOC stocks represented in GFDL-ESM4 projections. Among 56 environmental predictors, we found 12 as dominant controllers across all ecoregions. The adjusted geospatial model with the 12 environmental controllers showed an R2 of 0.48 in testing dataset. Higher precipitation and lower temperatures were associated with higher levels of SOC stocks in majority of ecoregions. Changes in land cover types (vegetation properties) was important in drier ecosystem as North American deserts, whereas soil types and topography were more important in American prairies. Wetlands of the Everglades was highly sensitive to projected temperature changes. The SOC stocks did not change under SSP126 until 2100, however SOC stocks decreased up to 21% under SSP585. Our results, based on environmental controllers of SOC stocks, help to predict impacts of changing environmental conditions on SOC stocks more reliably and may reduce uncertainties found in both, geospatial and Earth System Models. In addition, the description of different environmental controllers for US ecoregions can help to describe the scope and importance of global and local models.

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Opener, packer wheel and packing force effects on crop emergence and yield of direct seeded wheat, canola and field peas

Canadian Journal of Plant Science ◽

10.4141/p01-171 ◽

2003 ◽

Vol 83 (1) ◽

pp. 129-139 ◽

Cited By ~ 7

Author(s):

A. M. Johnston ◽

G. P. Lafond ◽

W. E. May ◽

G. L. Hnatowich ◽

G. E. Hultgreen

Keyword(s):

Grain Yield ◽

Environmental Conditions ◽

Direct Seeding ◽

Soil Conditions ◽

High Soil Moisture ◽

Pea Seedlings ◽

Field Peas ◽

Furrow Opener ◽

Direct Seeded ◽

Moisture Conditions

An understanding of the effects of different opener designs and on-row packing force would help producers in their selection of appropriate direct seeding implement options for their soil conditions. A field trial was conducted at three locations (Indian Head, Sylvania and Watrous) in Saskatchewan from 1997 to 1999 to evaluate the effect of opener-packer design (spoon-steel V packer; spoon-flat rubber packer; paired row-steel V packer; paired row-flat rubber packer; sweep-pneumatic tire) in combination with a range of on-row packing forces [0, 333, 549, 746, and 1000 Newton (N) per press wheel] on crop emergence and grain yield with direct seeding. The differences observed between opener-packer combinations in this study varied by less than 10% for grain yield, and were almost always associated with the opener design and not the packer type. Despite the variable results, there was a tendency for higher pea and wheat emergence with the sweep + tire compared with other opener types at those locations that tended to be drier in the spring. Also, grain yield tended to be greater for the sweep + tire in 1999 at Indian Head, when the heavy-textured soil at this site had high soil moisture conditions at seeding. The responses to packing force varied with different years and among the crops. Generally, 333 N per press wheel provided adequate emergence and grain yield across the environmental conditions encountered in this study, regardless of the opener-packer combination. In 1997, 5% more pea seedlings emerged with some amount of packing compared with no packing. Relative to the check, some packing resulted in wheat grain yield that was 13% greater at three of the location-by-year combinations, and wheat emergence that was 9% greater in 1998. However, with canola excessive packing force (i.e., the two highest vs. lower packing forces) resulted in 11 fewer seedlings m-2 in 1999. A packing pressure of 333 N per press wheel provided adequate emergence and grain yield across varied environmental conditions, with higher packing force only negatively influencing emergence in canola, and not yield. Key words: Furrow opener, packing force, emergence, direct seeding, zero till

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Rehabilitation of degraded areas in northeastern Patagonia, Argentina: Effects of environmental conditions and plant functional traits on performance of native woody species

Journal of Arid Land ◽

10.1007/s40333-020-0021-x ◽

2020 ◽

Vol 12 (4) ◽

pp. 653-665

Author(s):

Juan M. Zeberio ◽

Carolina A. Pérez

Keyword(s):

Functional Traits ◽

Environmental Conditions ◽

Woody Species ◽

Plant Functional Traits ◽

Native Woody Species

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Functional traits related to seedling performance in the Mediterranean leguminous shrub Retama sphaerocarpa: Insights from a provenance, fertilization, and rhizobial inoculation study

Environmental and Experimental Botany ◽

10.1016/j.envexpbot.2008.04.005 ◽

2008 ◽

Vol 64 (2) ◽

pp. 145-154 ◽

Cited By ~ 26

Author(s):

Pedro Villar-Salvador ◽

Fernando Valladares ◽

Susana Domínguez-Lerena ◽

Beatriz Ruiz-Díez ◽

Mercedes Fernández-Pascual ◽

...

Keyword(s):

Functional Traits ◽

Seedling Performance ◽

Retama Sphaerocarpa ◽

Rhizobial Inoculation ◽

The Mediterranean ◽

Inoculation Study

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Maximum entropy models elucidate the contribution of metabolic traits to patterns of community assembly

10.1101/526764 ◽

2019 ◽

Cited By ~ 1

Author(s):

Jason Bertram ◽

Erica A Newman ◽

Roderick Dewar

Keyword(s):

Community Structure ◽

Maximum Entropy ◽

Functional Traits ◽

Community Assembly ◽

Species Abundance ◽

Metabolic Rates ◽

Species Identity ◽

Metabolic Traits ◽

Abundance Patterns ◽

Species Specific

Aim: Maximum entropy (MaxEnt) models promise a novel approach for understanding community assembly and species abundance patterns. One of these models, the "Maximum Entropy Theory of Ecology" (METE) reproduces many observed species abundance patterns, but is based on an aggregated representation of community structure that does not resolve species identity or explicitly represent species-specific functional traits. In this paper, METE is compared to "Very Entropic Growth" (VEG), a MaxEnt model with a less aggregated representation of community structure that represents species (more correctly, functional types) in terms of their per capita metabolic rates. We examine the contribution of metabolic traits to the patterns of community assembly predicted by VEG and, through aggregation, compare the results with METE predictions in order to gain insight into the biological factors underlying observed patterns of community assembly. Innovation: We formally compare two MaxEnt-based community models, METE and VEG, that differ as to whether or not they represent species-specific functional traits. We empirically test and compare the metabolic predictions of both models, thereby elucidating the role of metabolic traits in patterns of community assembly. Main Conclusions: Our analysis reveals that a key determinant of community metabolic patterns is the "density of species" distribution, defined as the intrinsic number of species with metabolic rates in a given range that are available to a community prior to filtering by environmental constraints. Our analysis suggests that appropriate choice of of the density of species in VEG may lead to more realistic predictions than METE, for which this distribution is not defined, and thus opens up new ways to understanding the link between functional traits and patterns of community assembly.

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The Influences of Disturbance Histories and Soil Properties on Aboveground Biomass through Plant Functional Traits in a Tropical Rainforest

Forests ◽

10.3390/f10090774 ◽

2019 ◽

Vol 10 (9) ◽

pp. 774 ◽

Cited By ~ 1

Author(s):

Wensheng Bu ◽

Cancan Zhang ◽

Jihong Huang ◽

Runguo Zang ◽

Yi Ding ◽

...

Keyword(s):

Environmental Factors ◽

Soil Properties ◽

Functional Traits ◽

Environmental Conditions ◽

Aboveground Biomass ◽

Ecosystem Functioning ◽

Plant Functional Traits ◽

Old Growth ◽

Adult Trees ◽

Adult Tree

Research Highlights: We try to evaluate the relative contribution of environmental factors and functional traits on aboveground biomass in a species rich tropical forest ecosystem after a 40-years natural recovery. Background and Objectives: Functional traits have a potential to incorporate community dynamics into the impacts of disturbance histories or environmental conditions on ecosystem functioning, but few studies have been conducted to understand these processes. Materials and Methods: We measured plant functional traits and soil properties in the tropical montane rainforests on Hainan Island, China, which had experienced different disturbance histories (clear cutting, selective logging, and old-growth) 40 years ago. A structural equation model was used to elucidate how disturbance histories and soil factors influence aboveground biomass (AGB) across different size classes (saplings, treelets, and adult trees) through plant functional traits. Results: The results demonstrated logging stimulated seedling establishment but decreased AGB of adult trees and wood density at community-level (CWM_WD) of sapling and adult tree. Generally, CWM_WD of sapling, treelet, and adult tree decreased linearly with the increasing of specific leaf area at community-level (CWM_SLA) in old-growth forest and these two disturbed forests. Moreover, CWM_SLA explained more variation of CWM_WD with increasing intensity of logging within sapling, treelet, and adult tree. CWM_SLA and CWM_WD not only responded to environmental conditions and disturbance intensity but also affected AGB in all size classes; meanwhile, CWM_SLA was a major driver of AGB. CWM_SLA had a stronger effect on AGB in sapling and treelet classes than on the adult tree class. Conclusions: Our results suggested that disturbance history and environmental factors could directly or indirectly affect ecosystem functioning through plant functional traits. Functional traits always had a stronger effect on AGB than environmental conditions. Moreover, CWM_SLA is a key trait that can be used to link the relationship between environmental conditions and AGB.

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Functional traits of epiphytic lichens as potential indicators of environmental conditions in forest ecosystems

Ecological Indicators ◽

10.1016/j.ecolind.2011.12.006 ◽

2012 ◽

Vol 18 ◽

pp. 413-420 ◽

Cited By ~ 82

Author(s):

Paolo Giordani ◽

Giorgio Brunialti ◽

Giovanni Bacaro ◽

Juri Nascimbene

Keyword(s):

Functional Traits ◽

Environmental Conditions ◽

Forest Ecosystems ◽

Epiphytic Lichens

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Performance of carrot seeds possessing different germination rates within a seed lot

The Journal of Agricultural Science ◽

10.1017/s0021859600079739 ◽

1988 ◽

Vol 110 (1) ◽

pp. 93-99 ◽

Cited By ~ 3

Author(s):

W. E. Finch-Savage ◽

C. I. McQuistan

Keyword(s):

Environmental Conditions ◽

Coefficient Of Variation ◽

Germination Rate ◽

Seedling Emergence ◽

Seedling Performance ◽

Controlled Conditions ◽

Carrot Seed ◽

The Relationship ◽

Fluid Drilling

SummaryThe relationship between germination rate within a carrot seed lot and subsequent seedling performance was studied in four seed lots of different viability. Seedling performance was assessed using slope tests conducted under controlled conditions and in the field following fluid drilling under a range of environmental conditions. Germination rate within a seed lot was positively related to vigour measured by slope tests, percentage emergence and seedling weight, and was negatively related to the spread of emergence times (In variance days) and the coefficient of variation (c.v.) of seedling weights. Sowing seeds selected as fast germinating resulted in greater seedling emergence percentages over a range of environmental conditions than when sowing seeds selected as slowly germinating.

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