Impacts of black stain root disease in recently formed mortality centers in the piñon-juniper woodlands of southwestern Colorado

Thirty discrete black stain root disease (BSRD) mortality centers, caused by Leptographium wageneri (Kendr.) Wingf. var. wageneri, were examined in 1999 to determine the effects of BSRD on the composition and structure of piñonjuniper woodlands at the tree, shrub, and herbaceous plant levels and on tree-seedling regeneration. In these recently formed mortality centers, the majority (68%) of all piñon (Pinus edulis Engelm.) was dead, 76% of piñon were affected by BSRD, and 70% had evidence of piñon ips bark beetle (Ips confusus Leconte) attack. BSRD mortality centers had a mean area of 0.28 ha (range 0.07 to 0.63 ha). There were no statistically significant (p > 0.05) differences in shrub composition, cover, or diversity between mortality centers and the unaffected surrounding woodlands. Herbaceous plant cover was significantly greater (p < 0.001) within mortality centers and frequency responses were species specific. There were no significant (p = 0.629) differences in the density of piñon regeneration inside mortality centers compared with outside mortality centers. The pathogen was regularly isolated from piñon roots dead for 58 years and once from a root dead for 16 years. The rate of radial expansion of mortality centers averaged 1.1 m/year (0.07 SE). The rate of mortality center expansion was not significantly (p > 0.05) related to available water-holding capacity, percent organic matter, pH of soils, piñon density, or any other site data recorded.

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Variation in vegetation cover and seedling performance of tree species in a forest-savanna ecotone

Journal of Tropical Ecology ◽

10.1017/s0266467418000469 ◽

2019 ◽

Vol 35 (2) ◽

pp. 74-82 ◽

Cited By ~ 2

Author(s):

Hamza Issifu ◽

George K. D. Ametsitsi ◽

Lana J. de Vries ◽

Gloria Djaney Djagbletey ◽

Stephen Adu-Bredu ◽

...

Keyword(s):

Vegetation Cover ◽

Seedling Recruitment ◽

Seedling Survival ◽

Tree Cover ◽

First Year ◽

Transplant Experiment ◽

Tree Seedling ◽

Savanna Woodland ◽

Specific Effects ◽

Species Specific

AbstractDifferential tree seedling recruitment across forest-savanna ecotones is poorly understood, but hypothesized to be influenced by vegetation cover and associated factors. In a 3-y-long field transplant experiment in the forest-savanna ecotone of Ghana, we assessed performance and root allocation of 864 seedlings for two forest (Khaya ivorensis and Terminalia superba) and two savanna (Khaya senegalensis and Terminalia macroptera) species in savanna woodland, closed-woodland and forest. Herbaceous vegetation biomass was significantly higher in savanna woodland (1.0 ± 0.4 kg m−2 vs 0.2 ± 0.1 kg m−2 in forest) and hence expected fire intensities, while some soil properties were improved in forest. Regardless, seedling survival declined significantly in the first-year dry-season for all species with huge declines for the forest species (50% vs 6% for Khaya and 16% vs 2% for Terminalia) by year 2. After 3 y, only savanna species survived in savanna woodland. However, best performance for savanna Khaya was in forest, but in savanna woodland for savanna Terminalia which also had the highest biomass fraction (0.8 ± 0.1 g g−1 vs 0.6 ± 0.1 g g−1 and 0.4 ± 0.1 g g−1) and starch concentration (27% ± 10% vs 15% ± 7% and 10% ± 4%) in roots relative to savanna and forest Khaya respectively. Our results demonstrate that tree cover variation has species-specific effects on tree seedling recruitment which is related to root storage functions.

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RESTORATION OF FORMER GRASSLAND IN SOUTH-CENTRAL TEXAS

Texas Journal of Science ◽

10.32011/txjsci_71_1_article2 ◽

2019 ◽

Vol 71 (1) ◽

Author(s):

Wendy J. Leonard ◽

O. W. Van Auken

Keyword(s):

San Antonio ◽

Plant Cover ◽

Woody Species ◽

Bare Soil ◽

Grass Species ◽

Herbaceous Plant ◽

Percent Cover ◽

Juniperus Ashei ◽

South Central ◽

Central Texas

Abstract In the past, grasslands and savannas were common in many areas of south-central Texas, including the San Antonio area. With the advent of European settlers and their livestock, much of this area was converted to agriculture and rangeland. Today, most of San Antonio is developed, but some preservation has occurred. Restored grassland, mechanically cleared of Juniperus ashei (juniper, Ashe juniper) and other woody species in 2013, was examined and compared to adjacent non-cleared woodland. The woodland examined was dominated by Diospyros texana (Texas persimmon) and Juniperus ashei. Richness in the woodland canopy was 15 species. The understory below the canopy had 25 woody species. In the restored grassland area, herbaceous plant cover was 41.8%, woody plant cover 5.8%, bare soil 2.9%, and litter cover 49.5%. Species richness was 71, with 60 herbaceous and 11 woody species (percent cover of each from <0.1–7.1%). The most common species in the restored grassland in descending order were Nassella leucotricha (Texas winter grass), Calyptocarpus vialis (straggler daisy), Carex planostachys (cedar sedge), Sporobolus crypandrus (sand dropseed), D. texana, and Verbesina virginica (frost weed). Several C4 grass species were present with low cover but may increase in abundance over time. Four of the six most common restored grassland species were present below the woodland canopy and 12 woody species were present in the restored grassland as juveniles. Cost of restoration was approximately $38,500 ($7,500 supplies, $31,000 labor).

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Effects of different nanoparticles and biochar application on the biological indicators of a polluted mine soil

10.5194/egusphere-egu21-8247 ◽

2021 ◽

Author(s):

Rubén Forján Castro ◽

Diego Baragaño Coto ◽

Daniel Arenas Lago ◽

José Luis Rodríguez Gallego ◽

Erika Silva Santos

Keyword(s):

Contaminated Soils ◽

Iron Nanoparticles ◽

Plant Cover ◽

Treatment Plant ◽

Biological Indicators ◽

Enzymatic Activities ◽

Herbaceous Plant ◽

Mine Soil ◽

Hydroxyapatite Nanoparticles ◽

Commercial Mixture

In active mines areas without environmental management plans or abandoned mines, the mineral processing and mining-waste disposal are common sources of pollution that can affect large areas comprising soils and waters. Inevitably this situation leads to a degradation of plant cover whether natural or planted. Thus, a sustainable recovery of mine tailings and contaminated soils, located inside or surrounding the mine area is necessary, especially with innovative strategies for in situ elements stabilization. Within different stabilization options, nanoremediation, i.e. amending with nanomaterials (usually Fe-based nanoparticles) alone or combined with other amendments, is an interesting approach. Most of the studies are focused on the immobilization of metal(oid)s by nanoparticles, however only a few works assess the effects of these amendments on contaminated soils on their microbiology and plants. For these reasons, the main scope of this study was the assessment of some biological indicators, namely several enzymatic activities in soils and plant development, of a contaminated mine soil amended with two different types of commercial nanoparticles (iron nanoparticles nZVI and hydroxyapatite nanoparticles) and their combinations with biochar (by PYREG Carbon Technology Solutions, was made from wood following the PYREG&#174; methodology). The studied soil belongs to a broad mining area in NW Spain and it revealed high total concentrations of Cu and As (5000 and 300 mg/kg, respectively). The mine soil was amended in a factorial experiment in pots assay, under controlled conditions in greenhouse, with iron nanoparticles (nZVI), hydroxyapatite nanoparticles (nHP), biochar, and the combination of nZVI+biochar and nHP+biochar. In these pots was sown a commercial mixture of herbaceous plant species for pasture being monitored for 45 days. Plant cover was determined and once this assay time had elapsed, four enzymatic activities (dehydrogenase, &#946;-glucosidase, acid phosphatase and urease) of the soil and biomass weight was analyzed.Only rye grass germinated. Same result was verified in the pot assay and independently of treatment. Plant cover in all treatments was similar reaching more than 80 %, however dry plant biomass varied. Notable differences were observed in the enzymatic activity among the soil amended only with nanoparticles, the soil amended with the combination of nanoparticles and biochar or biochar alone. In general, the application of studied amendments, alone or combined and compared to the control, increased the functioning of the overall microbial community and microbial communities associated to C and N cycling. The soil amended with biochar and biochar combined with nanoparticles presented a greater enzymatic activities in the soil compared to the direct application of nanoparticles. A differentiation in the some enzymatic activities (e.g. dehydrogenase and urease) with the nanoparticles type was verified.&#160;Acknowledgment: This work was supported by the research project NANOCAREM MCI-20-PID2019-106939GB-I00 (AEI/FEDER, UE) and Portuguese funds through Funda&#231;&#227;o para a Ci&#234;ncia e Tecnologia within the scope of the project UID/AGR/04129/2020 (LEAF). The authors thanks the grants: Arenas-Lago D. (postdoc contract ED481D 2019/007) and Baraga&#241;o D. (Formaci&#243;n del Profesorado Universitario program) financed by of Xunta de Galicia and Universidade de Vigo and Ministerio de Educaci&#243;n, Cultura y Deporte de Espa&#241;a, respectively.&#160;

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Species-specific flowering phenology responses to experimental warming and drought alter herbaceous plant species overlap in a temperate–boreal forest community

Annals of Botany ◽

10.1093/aob/mcaa156 ◽

2020 ◽

Author(s):

Karen E Rice ◽

Rebecca A Montgomery ◽

Artur Stefanski ◽

Roy L Rich ◽

Peter B Reich

Keyword(s):

Species Interactions ◽

Summer Rainfall ◽

Flowering Phenology ◽

Forest Community ◽

Herbaceous Plant ◽

Experimental Warming ◽

Ambient Conditions ◽

Climate Conditions ◽

Herbaceous Perennials ◽

Species Specific

Abstract Background and Aims Warmer temperatures and altered precipitation patterns are expected to continue to occur as the climate changes. How these changes will impact the flowering phenology of herbaceous perennials in northern forests is poorly understood but could have consequences for forest functioning and species interactions. Here, we examine the flowering phenology responses of five herbaceous perennials to experimental warming and reduced summer rainfall over 3 years. Methods This study is part of the B4WarmED experiment located at two sites in northern Minnesota, USA. Three levels of warming (ambient, +1.6 °C and +3.1 °C) were crossed with two rainfall manipulations (ambient and 27 % reduced growing season rainfall). Key Results We observed species-specific responses to the experimental treatments. Warming alone advanced flowering for four species. Most notably, the two autumn blooming species showed the strongest advance of flowering to warming. Reduced rainfall alone advanced flowering for one autumn blooming species and delayed flowering for the other, with no significant impact on the three early blooming species. Only one species, Solidago spp., showed an interactive response to warming and rainfall manipulation by advancing in +1.6 °C warming (regardless of rainfall manipulation) but not advancing in the warmest, driest treatment. Species-specific responses led to changes in temporal overlap between species. Most notably, the two autumn blooming species diverged significantly in their flowering timing. In ambient conditions, these two species flowered within the same week. In the warmest, driest treatment, flowering occurred over a month apart. Conclusions Herbaceous species may differ in how they respond to future climate conditions. Changes to phenology may lead to fewer resources for insects or a mismatch between plants and pollinators.

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Short-duration rotational grazing leads to improvements in landscape functionality and increased perennial herbaceous plant cover

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2019.04.031 ◽

2019 ◽

Vol 281 ◽

pp. 134-144 ◽

Cited By ~ 3

Author(s):

Rachel Lawrence ◽

R.D.B. Whalley ◽

Nick Reid ◽

Romina Rader

Keyword(s):

Short Duration ◽

Plant Cover ◽

Herbaceous Plant ◽

Rotational Grazing ◽

Perennial Herbaceous Plant ◽

Landscape Functionality

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Influence of Sulfonylurea and Other Herbicides on Selected Woody and Herbaceous Species

Weed Science ◽

10.1017/s0043174500056484 ◽

1990 ◽

Vol 38 (3) ◽

pp. 249-255 ◽

Cited By ~ 5

Author(s):

Robert E. Meyer ◽

Rodney W. Bovey

Keyword(s):

Plant Cover ◽

Woody Species ◽

Herbaceous Plant ◽

Herbaceous Species ◽

Grass Cover ◽

Weed Cover ◽

Broadleaf Species ◽

Honey Mesquite

Chlorsulfuron and metsulfuron were effective on Texas whitebrush, killing 70 to 75% of the plants at 0.28 kg ai ha, marginally effective on Macartney rose, killing 15 to 43% of the plants at 1.12 kg ha, but ineffective on honey mesquite and huisache, killing no more than 10% of the plants at 1.12 kg ha. Sulfometuron was ineffective on all woody species at 1.12 kg ai ha. Clopyralid and picloram were effective, killing 70 to 92% of the huisache at 2.24 kg ae ha. Tebuthiuron killed 72% of the Texas whitebrush at 1.12 kg ai ha. Sulfometuron generally reduced herbaceous plant cover the year of application. Chlorsulfuron and metsulfuron often resulted in increased grass cover the year of application. Most herbicides reduced broadleaf weeds the year of application. Woolly croton often was the first prominent broadleaf species to return to areas treated with clopyralid and sulfometuron. Few differences occurred among herbicides in herbaceous weed cover the year following treatment.

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Herbaceous plant cover establishment on highway road sides

Eco-and Ground Bio-Engineering: The Use of Vegetation to Improve Slope Stability - Developments in Plant and Soil Sciences ◽

10.1007/978-1-4020-5593-5_39 ◽

2007 ◽

pp. 387-391 ◽

Cited By ~ 1

Author(s):

Z. Koukoura ◽

A. Kyriazopoulos ◽

I. Karmiris

Keyword(s):

Plant Cover ◽

Herbaceous Plant

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The acoustic multifrequency classification of two sympatric euphausiid species (Meganyctiphanes norvegica and Thysanoessa raschii), with empirical and SDWBA model validation

ICES Journal of Marine Science ◽

10.1093/icesjms/fst004 ◽

2013 ◽

Vol 70 (3) ◽

pp. 636-649 ◽

Cited By ~ 25

Author(s):

Ian H. McQuinn ◽

Maxime Dion ◽

Jean-François St. Pierre

Keyword(s):

Model Validation ◽

Fishery Management ◽

Noise Removal ◽

Trophic Levels ◽

Angle Distribution ◽

Acoustic Frequency ◽

Frequency Responses ◽

Meganyctiphanes Norvegica ◽

Species Specific

Abstract McQuinn, I. H., Dion, M., and St. Pierre, J.-F. 2013. The acoustic multifrequency classification of two sympatric euphausiid species (Meganyctiphanes norvegica and Thysanoessa raschii), with empirical and SDWBA model validation. – ICES Journal of Marine Science, 70: 636–649. The ecosystem approach to fishery management requires monitoring capabilities at all trophic levels, including pelagic organisms. However, the usefulness of active acoustics for ecosystem monitoring has been limited by ambiguities in the identification of scattering layers. Increasingly, multifrequency acoustic methods are being developed for the classification of scattering layers into species or species groups. We describe a method for distinguishing between sympatric northern and Arctic krill (Meganyctiphanes norvegica and Thysanoessa raschii) using sv amplitude ratios from 38, 120, and 200 kHz data which were pre-processed through a self-noise removal algorithm. Acoustic frequency responses of both euphausiid species were predicted from species-specific parameterizations of a SDWBA physical model using specific body forms (shape, volume, and length) for Arctic and northern krill. Classification and model validation were achieved using macrozooplankton samples collected from multiple-sampler (BIONESS) and ringnet (JackNet) hauls, both equipped with a strobe light to reduce avoidance by euphausiids. SDWBA frequency responses were calculated for a range of orientations (± 45°) and compared with observed frequency responses, solving for orientation by least squares. A tilt angle distribution of N[9°,4°] and N[12°,6°] for T. raschii and M. norvegica, respectively resulted in best fits. The models also provided species-specific TS–length relationships.

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The gut bacterial microbiota of sea turtles differs between geographically distinct populations

Endangered Species Research ◽

10.3354/esr01042 ◽

2020 ◽

Vol 42 ◽

pp. 95-108

Author(s):

TF Scheelings ◽

RJ Moore ◽

TTH Van ◽

M Klaassen ◽

RD Reina

Keyword(s):

Sea Turtles ◽

Microbial Community Composition ◽

Sea Turtle ◽

Microbial Composition ◽

Bacterial Microbiota ◽

Composition And Structure ◽

Loggerhead Turtles ◽

Breeding Grounds ◽

The Usa ◽

Species Specific

The microbiota of metazoans can be influenced by a variety of factors including diet, environment and genetics. In this study we sampled multiple populations from 2 host species that do not overlap in distribution, in order to test whether their bacterial microbiotas are species-specific or more variable. Intestinal swabs were collected from loggerhead turtles originating from Florida, USA, and Queensland, Australia, as well as from flatback turtles from Crab Island, Queensland, and Port Hedland, Western Australia. We then manually extracted bacterial DNA and used 16S rRNA sequencing to explore bacterial microbial community composition and structure. Our investigation showed that the bacterial microbiota of sea turtles is heavily influenced by geography, with loggerhead turtles originating from the USA and Australia harbouring significantly different bacterial microbial populations in terms of composition. Similarly, we also found that flatback turtles from Crab Island had significantly less diverse microbiotas, with a predominance of the bacterial phylum Firmicutes, in comparison to their genetically similar counterparts from Port Hedland. Factors that may explain these observed differences between populations include host genetics, differences in foraging habitat quality and differences in migratory distance (and thus durations of inappetence) between foraging and breeding grounds. The mechanisms by which these factors may influence bacterial microbial composition of sea turtle gastrointestinal tracts warrants further investigation. The results of this study highlight the importance of interpreting microbiota data of wild animals in the context of geography.

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