Find research datasets worth reusing

opencc-by-4.0Feb 2015View details →

Fig. 1 in First investigation on the diet of the eastern grass owl during the nesting period in Thailand

Fig. 1. Typical pellet of an eastern grass owl (left) and a Circus harrier (right).

opencc-by-4.0Feb 2015View details →

Fig. 2 in First investigation on the diet of the eastern grass owl during the nesting period in Thailand

Fig. 2. Different sizes of pellets and prey's skulls of eastern grass owl.

opencc-zeroNov 2022View details →

Data from: Demographic effects of a megafire on a declining prairie grouse in the mixed-grass prairie

Recent studies have documented benefits of small, prescribed fire and wildfire for grassland-dependent wildlife, such as lesser prairie-chickens (Tympanuchus pallidicintus), but wildlife demographic response to the scale and intensity of megafire (wildfire > 40,000 ha) in modern fragmented grasslands remains unknown. Limited available grassland habitat makes it imperative to understand if increasing frequency of megafires could further reduce already declining lesser prairie-chicken populations, or if historical evolutionary interactions with fire make lesser prairie-chickens resilient. To evaluate lesser prairie-chicken demographic response to megafires, we compared lek counts, nest density, and survival rates of adults, nests, and chicks before (2014–2016) and after (2018–2020) a 2017 megafire in the mixed-grass prairie of Kansas, USA (Starbuck fire ~254,000 ha). There was a 67% decline in attending males on leks post-fire and a 46% decline in occupied leks post-fire. Despite population declines as indicated by lek counts, adult female breeding season survival (Ŝ) was similar pre- (Ŝ = 0.65 ± 0.08 [SE]) and post-fire (0.61 ± 0.08), as was chick survival (pre-fire: 0.23 ± 0.07; post-fire: 0.27 ± 0.11). Nest survival appeared lower post-fire (pre-fire: 0.38 ± 0.06; post-fire: 0.20 ± 0.06), but did not differ at the 95% confidence interval. Nest density of marked females declined 73% in areas burned by megafire. Although lesser prairie-chickens persisted in the study area and we documented minimal effects on most demographic rates, reduced lesser prairie-chicken abundance and reproductive output suggests full recovery may take >3 years. Increased propensity for megafire resulting from suppression of smaller fires, compounded by climate change and woody encroachment, may impose a short-term (3-5 year) threat to already declining lesser prairie-chicken populations.

opencc-zeroDec 2022View details →

Data for: Invasion by an exotic grass species homogenises native freshwater plant communities

A growing body of evidence has shown that biological invasions cause shifts in species composition of communities in space and time. Although biological invasions are considered a major driver of biotic homogenisation worldwide, most previous studies are conducted at small spatial scales and over short time periods, which may have underestimated the impacts of exotic species on native communities. Using a unique dataset of aquatic plants sampled in 235 sites over 12 years (2007–2010 and 2015–2019) in a large reservoir (Itaipu Reservoir; 1,350 km²), we analyzed how the invasion of a non-native grass (Urochloa arrecta) affects the species richness, ecological uniqueness (i.e., local contribution to beta diversity – LCBD) and temporal β–diversity of native plant communities. From 3,934 surveyed plant communities, U. arrecta was recorded in 2,888 samples and it was absent from 1,046 samples. Overall, species richness and ecological uniqueness of native plant communities were markedly lower in sites invaded than non-invaded by U. arrecta. From 2007 to 2019, the ecological uniqueness of native plants was 60% lower in the invaded than non-invaded sites. Whereas in invaded sites the species loss was the dominant mechanism driving native communities over time, in non–invaded sites the gain of new native species was the primary mechanism underlying community trajectories. Moreover, comparing native plant communities before and after the invasion of U. arrecta, species richness, ecological uniqueness and species gains of native plant communities decreased, whereas species losses increased after the invasion of U. arrecta. Finally, the positive relationship between native biodiversity and precipitation was stronger in sites non-invaded than invaded by U. arrecta. Synthesis: Our findings provide comprehensive evidence that an invasive plant is decreasing the spatial and temporal β–diversity of native plant communities through declining species richness, rather than simply correlating with them. This suggests that U. arrecta is driving native plants to become less diverse and homogeneous after the invasion, both spatially and temporally. Our findings illustrate that at broad scales, aquatic plant communities may become increasingly homogeneous with the increasing number of biological invasion events taking place worldwide.

opencc-zeroDec 2022View details →

Alloteropsis semialata as a study system for C4 evolution in grasses

Background Numerous groups of plants have adapted to CO2 limitations by independently evolving C4 photosynthesis. This trait relies on concerted changes in anatomy and biochemistry to concentrate CO2 within the leaf and thereby boost productivity in tropical conditions. The ecological and economical importance of C4 photosynthesis has motivated intense research, often relying on comparisons between distantly related C4 and non-C4 plants. The photosynthetic type is fixed in most species, with the notable exception of the grass Alloteropsis semialata. This species includes populations exhibiting the ancestral C3 state in southern Africa, intermediate C3+C4 populations in the Zambezian region and C4 populations spread around the paleotropics. Scope We compile here the knowledge on the distribution and history of Alloteropsis as a whole and discuss how this has furthered our understanding of C4 evolution. We further generate a chromosome-level reference genome for a C3 individual and compare the genomic architecture to that of a C4 accession. Conclusions Alloteropsis semialata represents one of the best systems to investigate the evolution of C4 photosynthesis as the genetic and phenotypic variation provides a fertile ground for comparative and population-level studies. Initial comparative genomics show the C3 and C4 genomes are highly syntenic and have undergone a modest amount of gene duplication and translocation since the different photosynthetic groups divided. The background knowledge and publicly available genomic resources make Alloteropsis semialata a great model for further comparative analyses of photosynthetic diversification.

opencc-by-4.0Dec 2022View details →

Inter- and infraspecific plant-soil feedbacks of grass species

Plants continuously interact with soil microbiota. These plant-soil feedbacks (PSFs) are considered a driving force in plant community dynamics. However, most PSF information comes from inter-family studies, with limited information on possible causes. We studied the variation of PSFs between and within grass species and identified the soil microbes that are associated with the observed PSFs effects. We grew monocultures of ten cultivars of three grass species (Lolium perenne, Poa pratensis, Schedonorus arundinaceus) using a two-phase PSF experiment. We measured plant total biomass to determine PSFs between and within species and correlated it with sequenced rhizosphere bacteria and fungi. In the soil conditioning phase, grass species developed microbial legacies that affected the performance of other grass species in the feedback phase.  We detected overall negative interspecific PSFs. While we show that L. perenne and P. pratensis increased their performance respectively in conspecific and heterospecific soils, S. arundinaceus was not strongly affected by the legacies of the previous plant species. Contrary to our expectation, we found no evidence for intraspecific variation in PSFs. Bacterial taxa associated with PSFs included members of Proteobacteria, Firmicutes, Verrucomicrobia and Planctomycetes whereas fungal taxa included members of Ascomycota. Our results suggest differences in PSF effects between grass species, but not between cultivars within species. Thus, in the studied grass species, there might be limited potential for breeding on plant traits mediated by PSFs. Furthermore, we point out potential microbial candidates that might be driving the observed PSF effects that could be further explored.

opencc-by-4.0Jul 2022View details →

Herbicide resistance in black grass in LU - Treer et al.

The file contains the raw data of the manuscript " Overrepresentation of Alopecurus myosuroides with high levels of resistance towards herbicides applied in spring on heavy clay soils" by Treer S, Scherer K, Pallez-Barthel M, Dam D, Beyer M

opencc-zeroFeb 2023View details →

Does the effect of flowering time on biomass allocation across latitude differ between invasive and native salt marsh grass Spartina alterniflora?

Parallel latitudinal clines in flowering time have been documented in both the invasive and native ranges of plants. Furthermore, flowering time has been found to affect biomass at maturity. Therefore, understanding how these flowering times affect biomass accumulation across latitude is essential to understanding plant adaptations and distributions. We investigated and compared trends in first flowering day (FFD), aboveground biomass (AGB), belowground biomass (BGB) and BGB:AGB ratio of the salt marsh grass Spartina alterniflora along latitudinal gradients from the invasive (China, 19-40o N) and native range (United States, 27-43o N) in a greenhouse common garden experiment, and tested whether FFD would drive these divergences between invasive and native ranges. The invasive populations produced more (~20%, ~19%) AGB and BGB than native populations, but there were no significant differences in the FFD and BGB:AGB ratio. We found significant parallel latitudinal clines in FFD in both invasive and native ranges. In addition, the BGB:AGB ratio was negatively correlated with the FFD in both the invasive and native ranges but non-significant in invasive populations. In contrast, AGB and BGB increased with latitude in the invasive range, but declined with latitude in the native range. Most interestingly, we found AGB and BGB positively correlated with the FFD in the native range, but no significant relationships in the invasive range. Our results indirectly support the evolution of increased competitive ability hypothesis (EICA) that S. alterniflora has evolved to produce greater AGB and BGB in China, and climatic conditions in the native might select for a flowering and allocation pattern is maintained in the invasive range. Our results also suggest that invasive S. alterniflora in China is not constrained by the trade-off of earlier flowering with smaller size, and that flowering time has played an important role on biomass allocation across latitude.

opencc-zeroApr 2023View details →

Drought susceptibility of southern African C4 grasses: phylogenetically and photosynthetically determined?

<ol> <li> Factors that determine C4 grass distributions have been well documented, with evidence in the literature for C4 photosynthetic subtypes displaying varying levels of drought susceptibility. However, the interactions between C4 photosynthetic subtype and phylogeny add complexity and are relatively under-studied. </li> <li>We use species distribution modelling to determine the influence of rainfall on distribution patterns of representative C4 grass families and subtypes. Select C4 grass species, representing different photosynthetic subtypes (NADP-Me and NAD-Me) and lineages (Panicoideae and Aristidoideae), were then subjected to a progressive 58-day drought period and recovery phase, to explore drought responses through leaf water relations, gas exchange and chlorophyll fluorescence. </li> <li>We show Panicoideae NADP-Me species to be more susceptible to drought than both Panicoideae NAD-Me and Aristidoideae NADP-Me species due to apparent greater metabolic impairment. The differences between groups were related to how rapidly photosynthesis declines with exposure to drought and the rate of recovery post-drought, rather than the maximum extent of photosynthetic decline. The mechanisms for the relative maintenance of plant water status differed between the Panicoideae NAD-Me species, which utilised greater stomatal control, and the Aristidoideae NADP-Me species, which maintained water uptake through osmotic adjustment. </li> <li> Synthesis: We show here that drought susceptibility differs both phylogenetically and according to photosynthetic subtype, but that the role of phylogeny may outweigh physiological control. This research adds novel insight into the physiological differences behind observed rainfall-related differences in C4 grass distribution patterns. </li> </ol>

opencc-zeroMay 2023View details →

Sensitivity of different grass functional groups to honey mesquite

Quantifying the relationship of different grass functional groups to increasing woody plant cover is necessary to better understand the effects of woody plant encroachment on grasslands. This study explored biomass production responses of three perennial grass groups based on photosynthetic pathway and potential canopy height (C4 short-grasses, C3 mid-grasses and C4 mid-grasses) to different percent canopy covers of the surrounding deciduous woody legume, honey mesquite (Prosopis glandulosa). Two methods were used to determine mesquite canopy cover, line-intercept and geospatial analysis of aerial images, and both were used to predict production of the 3 grass groups. Five years of grass production data were included in the mesquite cover/grass production regressions. Two years had extreme grass production responses, one due to drought and the other to high rainfall. Of the 3 remaining years, best-fit curves were negative linear for C4 short-grasses and C3 mid-grasses, and negative sigmoidal for C4 mid-grasses using both cover determination methods, although slopes of the curves differed between cover determination methods. C4 mid-grasses were more sensitive than the other grass groups to increasing mesquite cover. Loss of production potential when mesquite cover increased from 0–35% was 75.5, 28.7 and 23.2% for C4 mid-grasses, C3 mid-grasses and C4 short-grasses, respectively. Moreover, production potential of C4 mid-grasses under no mesquite cover was 3 and 6 times greater than C3 mid-grasses or C4 short-grasses, respectively. Spatial settings of the different grass groups in relation to mesquite tree size and size of intercanopy areas provided indirect evidence that the process of mesquite encroachment in the last 50 to 100 years may have negatively impacted C4 mid-grasses more than the other grass groups. Results suggest that gains in grass production following mesquite treatment would be limited if the system has degraded to where only C3 mid-grasses and C4 short-grasses dominate.

opencc-by-4.0Aug 2015View details →

Fig. 40 in Revision of the grass huntsman spider genus Pseudomicrommata Järvi, 1914 (Araneae: Sparassidae) in the Afrotropical Region

Fig. 40. Currently known distribution of Pseudomicrommata species.

opencc-zeroMay 2023View details →

Datasets and analysis for: Microclimatic buffering in forest, agricultural and urban landscapes through the lens of a grass-feeding insect

Using this dataset, we aimed to identify the microclimatic offsets that accurately represent the environment in which a small arthropod spends most of its life. As a case study, we selected grassy sites that corresponded to the microhabitat of grass-feeding insects in general, and larvae of the butterfly Pararge aegeria in particular, as this insect recently expanded its habitat use from forest (edges) to agricultural and urban environments. We tested to what extent local microclimates and microclimatic buffering capacity differed between tufts of grass in forest and in two anthropogenic (i.e. agricultural and urban) landscape settings by measuring microclimatic variables with sensors at the level of the grasses. We compared temperature, relative humidity and vapour pressure deficit (VPD) during an exceptionally warm and dry summer period with parallel data from weather stations and tested for differences between microclimatic profiles among the three landscape settings. Using this approach, our findings stress the functional implications of landscape-specific microclimatic profiles at the appropriate organism-centred scale.

opencc-by-4.0Jul 2023View details →

GRASS GIS Location for urban growth case study in Triangle area, NC, USA

GRASS GIS Location containing data prepared for a FUTURES urban growth modeling case study for the broader Raleigh-Durham area in North Carolina, USA. Contains NLCD 2001-2019 (land cover for all years; 2001 and 2019 impervious descriptor), county boundaries, USGS DEM, PAD-US protected areas.

opencc-by-4.0Dec 2021View details →

GRASS Input Data

This record contains the dataset that is used as input to GRASS v1.1.x. See <a href="https://github.com/palumbom/GRASS">https://github.com/palumbom/GRASS</a> for details and instructions.

Lateral gene transfer generates accessory genes that accumulate at different rates within a grass lineage

Lateral gene transfer (LGT) is the movement of DNA between organism without sexual reproduction. The acquired genes represent genetic novelties that have independently evolved in the donor's genome. Phylogenetic methods have shown that LGT is widespread across the entire grass family, although we know little about the underlying dynamics. We identify laterally acquired genes in five de novo reference genomes from the same grass genus (four Alloteropsis semialata and one Alloteropsis angusta). Using additional resequencing data for a further 40 Alloteropsis individuals, we place the acquisition of each gene onto a phylogeny using stochastic character mapping, and then infer rates of gains and losses. We detect 168 laterally acquired genes in the five reference genomes [32-100 per genome]. Exponential decay models indicate that the rate of LGT acquisitions [6-28 per Ma] and subsequent losses [11-24% per Ma] varied significantly among lineages. Laterally acquired genes were lost at a higher rate than vertically inherited loci [0.02-0.8% per Ma]. This high turnover creates intraspecific gene content variation, with a preponderance of them occurring as accessory genes in the Alloteropsis pangenome. This rapid turnover generates standing variation that can ultimately fuel local adaptation.

Data from: Different effects of fire age and fire recurrence on grass and woody plant chemistry in Kafue National Park, Zambia

In savannas, fire and herbivores are important drivers of natural ecosystem processes. Fire is also used intensively for management purposes. However, reported fire effects differ between studies. Reasons for these differences are still poorly understood. Here, we investigated the effects of fire on leaf chemistry of grasses and woody plants in the savanna of the Busanga Flood Plain, Zambia, in relation to the time elapsed between plant sampling and the last fire (fire age) and the frequency of fires during the last 16 years (fire recurrence). We analyzed leaves for their nitrogen, carbon and fiber concentrations, and estimated their metabolizable energy content, reflecting feed quality for browsers and grazers. Grasses and woody plants differed in all chemical components and showed different responses to fire. Grass quality was higher at sites burnt in the year of sample collection than at sites burnt only in previous years, but did not change under different fire recurrences. Leaves of woody plants did not differ in relation to fire age but their quality increased with increasing fire recurrence. In woody plants, the carbon content responded to the interaction between fire age and fire recurrence, indicating changes in carbon allocation in response to fire. Thus, burning increased feed quality for grazers and browsers but on different temporal scales. The scale effects may contribute to the differences in resource allocation described by different studies. They merit more attention in management decisions as well as in future studies on fire effects in savanna systems.

Root functional traits and growth rates in savanna trees and grasses

Root-based functional traits are relatively overlooked as drivers of savanna plant community dynamics, an important gap in water-limited ecosystems. Recent work has shed light on patterns of trait coordination in roots, but less is known about the relationship between root functional traits, water acquisition, and plant demographic rates. Here, we investigated how fine-root vascular and morphological traits are related in two dominant PFTs (C3 trees and C4 grasses from the savanna biome), whether root traits can predict plant relative growth rate (RGR), and whether root trait relationships differ in trees and grasses. We used root data from 21 tree and 18 grass species grown under greenhouse conditions, and quantified a suite of vascular and morphological root traits. We used a principal components analysis (PCA) to identify common axes of trait variation, compared trait correlation matrices between the two PFTs, and investigated the relationship between PCA axes and individual traits and RGR. We found that there was no clear single axis integrating vascular and morphological traits, but found that vascular anatomy predicted RGR in both trees and grasses. Trait correlation matrices differed in trees and grasses, suggesting potentially divergent patterns of trait coordination between the two functional types. Our results suggested that, despite differences in trait relationships between trees and grasses, root conductivity may constrain maximum growth rate in both PFTs, highlighting the critical role that water relations play in savanna vegetation dynamics and suggesting that root water transport capacity is an important predictor of plant performance in the savanna biome.

Silicon and Epichloë-endophyte defences in a model temperate grass diminish feeding efficiency and immunity of an insect folivore

Plants deploy diverse anti-herbivore defences which reduce feeding and performance of herbivores. Temperate grasses use silicon (Si) accumulation and Epichloë-endophytes for physical and chemical (i.e. endophytic-alkaloids) defence against insect herbivores. Recent studies suggest that Epichloë-endophytes increase Si accumulation in their host grass. It is unknown, however, how this affects Si-deposition on the leaf surface, their impacts on insect herbivore feeding efficiency and their immunity to potential infection/parasitism. To address this knowledge gap, we grew tall fescue (Festuca arundinacea) hydroponically with and without Si, in the absence or presence of the novel AR584 Epichloë-strain. We exposed plants to Helicoverpa armigera (Lepidoptera: Noctuidae) in both in-situ (intact leaves) and ex-situ (excised leaves) feeding trials and determined the effects of Si and endophyte defences on herbivore feeding efficiency, growth rates and immunity against potential infection/parasitism. Endophytic plants supplied with Si showed 110% and 143% increases in leaf silica density and leaf Si concentrations, respectively, when exposed to herbivory, compared to non-endophytic plants that were herbivore-free. Despite the endophyte-mediated increases in Si concentrations, H. armigera was only affected by Si supply; growth rates decreased by 87% and most feeding efficiency indices decreased by at least 30%. Si supply also increased mandibular wear by 16%, which was negatively correlated with H. armigera growth rates. Cellular and humoral immunity of H. armigera were negatively affected by both Si and endophytes. Endophytic-loline alkaloid concentrations were unaffected by Si supply or herbivory, whereas herbivory increased peramine concentrations by 290%. To our knowledge, this is the first report of Si defences and Epichloë-endophyte-derived alkaloids compromising insect immunity via reduced melanisation response. Using tall fescue and H. armigera, our study suggests that deploying both physical (i.e. Si accumulation) and chemical (i.e. endophytic-alkaloids) defences acting against multiple insect herbivore traits, including feeding efficiency, growth and immunity, may be a successful defence strategy in temperate grasses. This multi-faceted defence may be particularly difficult for insect herbivores to overcome.