scholarly journals Fungal communities living within leaves of native Hawaiian dicots are structured by landscape-scale variables as well as by host plants

2019 ◽  
Author(s):  
JL Darcy ◽  
SOI Switf ◽  
GM Cobian ◽  
G Zahn ◽  
BA Perry ◽  
...  
Keyword(s):  
Host Plant ◽  
Endophytic Fungi ◽  
Native Hawaiian ◽  
Spatial Scales ◽  
Leaf Tissue ◽  
Landscape Scale ◽  
Climatic Conditions ◽  
Bipartite Network ◽  
Plant Phylogeny ◽  
Dicotyledonous Plants

ABSTRACTA phylogenetically diverse array of fungi live within healthy leaf tissue of dicotyledonous plants. Many studies have examined these endophytes within a single plant species and/or at small spatial scales, but landscape-scale variables that determine their community composition are not well understood, either across geographic space, across climatic conditions, or in the context of host plant phylogeny. Here, we evaluate the contributions of these variables to endophyte beta diversity using a survey of foliar endophytic fungi in native Hawaiian dicots sampled across the Hawaiian archipelago. We used Illumina technology to sequence fungal ITS1 amplicons to characterize foliar endophyte communities across five islands and 80 host plant genera. We found that communities of foliar endophytic fungi showed strong geographic structuring between distances of seven and 36 km. Endophyte community structure was most strongly associated with host plant phylogeny and evapotranspiration, and was also significantly associated with NDVI, elevation, and solar radiation. Additionally, our bipartite network analysis revealed that the five islands we sampled each harbored significantly specialized endophyte communities. These results demonstrate how the interaction of factors at large and small spatial and phylogenetic scales shape fungal symbiont communities.

scholarly journals Various chemical groups produced by endophytic fungi isolated from the Calotropis procera- A pharmaceutically important xerophytic plant

2018 ◽  
Vol 9 (1) ◽  
pp. 82
Author(s):  
Vinibha Rajakumari I ◽  
Kalyanaraman Rajagopal ◽  
Sriraman V ◽  
Vanitha V ◽  
Mohanasundaram S
Keyword(s):  
Qualitative Analysis ◽  
Host Plant ◽  
Endophytic Fungi ◽  
Crude Extract ◽  
Leaf Tissue ◽  
Calotropis Procera ◽  
Chemical Groups

In the present study leaf tissue of host plant Calotropis procera was screened for the presence of endophytic fungi. The crude extract of the isolated endophytic fungi was tested for various chemical groups like alkaloids, flavonoids, diterpenoids and phenols. Our study showed the presence of 25 endophytic fungi isolated from the leaf tissue which constituted15 Hyphomycetes, 3 Ascomycetes, 3 Coelomycetes and 4 sterile forms. The qualitative analysis in all the 25 isolates showed the presence of alkaloid, phenol in 23 fungi, flavonoid in 19 and diterpenoids in 18 fungi. Fifteen endophytic fungi produced all chemical groups tested in the crude extract. Bipolaris sp a hyphomycete produced only one compound in culture. Among the four groups endophytic fungi Coelomycetes group able to produce all chemical groups tested. Keywords: Endophytic fungi; Alkaloid; Flavonoid; Diterpenoids

Mapping wildlife: integrating stakeholder knowledge with modelled patterns of deer abundance by using participatory GIS

2009 ◽  
Vol 36 (7) ◽  
pp. 553 ◽  
Author(s):  
Z. Austin ◽  
S. Cinderby ◽  
J. C. R. Smart ◽  
D. Raffaelli ◽  
P. C. L. White
Keyword(s):  
Community Involvement ◽  
Spatial Data ◽  
Spatial Scales ◽  
Stakeholder Participation ◽  
Landscape Scale ◽  
Scientific Data ◽  
Future Research ◽  
Economic Damage ◽  
Participatory Gis ◽  
Wild Deer

Context. Some species that are perceived by certain stakeholders as a valuable resource can also cause ecological or economic damage, leading to contrasting management objectives and subsequent conflict between stakeholder groups. There is increasing recognition that the integration of stakeholder knowledge with formal scientific data can enhance the information available for use in management. This is especially true where scientific understanding is incomplete, as is frequently the case for wide-ranging species, which can be difficult to monitor directly at the landscape scale. Aims. The aim of the research was to incorporate stakeholder knowledge with data derived from formal quantitative models to modify predictions of wildlife distribution and abundance, using wild deer in the UK as an example. Methods. We use selected predictor variables from a deer–vehicle collision model to estimate deer densities at the 10-km square level throughout the East of England. With these predictions as a baseline, we illustrate the use of participatory GIS as a methodological framework for enabling stakeholder participation in the refinement of landscape-scale deer abundance maps. Key results. Stakeholder participation resulted in modifications to modelled abundance patterns for all wild deer species present in the East of England, although the modifications were minor and there was a high degree of consistency among stakeholders in the adjustments made. For muntjac, roe and fallow deer, the majority of stakeholder changes represented an increase in density, suggesting that populations of these species are increasing in the region. Conclusions. Our results show that participatory GIS is a useful technique for enabling stakeholders to contribute to incomplete scientific knowledge, especially where up-to-date species distribution and abundance data are needed to inform wildlife research and management. Implications. The results of the present study will serve as a valuable information base for future research on deer management in the region. The flexibility of the approach makes it applicable to a range of species at different spatial scales and other wildlife conflict issues. These may include the management of invasive species or the conservation of threatened species, where accurate spatial data and enhanced community involvement are necessary in order to facilitate effective management.

scholarly journals Spatial Relationship between Precipitation and Runoff in Africa

2018 ◽  
Author(s):  
Fidele Karamage ◽  
Yuanbo Liu ◽  
Xingwang Fan ◽  
Meta Francis Justine ◽  
Guiping Wu ◽  
...  
Keyword(s):  
Land Surface ◽  
Spatial Scales ◽  
Spatial Relationship ◽  
Resource Planning ◽  
Climatic Conditions ◽  
Runoff Coefficient ◽  
Global Precipitation Climatology Centre ◽  
High Runoff ◽  
Monthly Runoff

Abstract. Lack of sufficient and reliable hydrological information is a key hindrance to water resource planning and management in Africa. Hence, the objective of this research is to examine the relationship between precipitation and runoff at three spatial scales, including the whole continent, 25 major basins and 55 countries. For this purpose, the long-term monthly runoff coefficient (Rc) was estimated using the long-term monthly runoff data (R) calculated from the Global Runoff Data Centre (GRDC) streamflow records and Global Precipitation Climatology Centre (GPCC) precipitation datasets for the period of time spanning from 1901 to 2017. Subsequently, the observed Rc data were interpolated in order to estimate Rc over the ungauged basins under guidance of key runoff controlling factors, including the land-surface temperature (T), precipitation (P) and potential runoff coefficient (Co) inferred from the land use and land cover, slope and soil texture information. The results show that 16 % of the annual mean precipitation (672.52 mm) becomes runoff (105.72 mm), with a runoff coefficient of 0.16, and the remaining 84 % (566.80 mm) evapotranspirates over the continent during 1901–2017. Spatial analysis reveals that the precipitation–runoff relationship varies significantly among different basins and countries, mainly dependent on climatic conditions and its inter-annual variability. Generally, high runoff depths and runoff coefficients are observed over humid tropical basins and countries with high precipitation intensity compared to those located in subtropical and temperate drylands.

scholarly journals Geomorphological indicators of large-scale climatic changes in the Eastern Bolivian lowlands

2006 ◽  
Vol 61 (2) ◽  
pp. 120-134 ◽  
Author(s):  
J. May
Keyword(s):  
South America ◽  
Large Scale ◽  
Climate Changes ◽  
Landscape Evolution ◽  
Spatial Scales ◽  
Climatic Changes ◽  
Climatic Conditions ◽  
Fluvial Erosion ◽  
Paleoclimatic Significance ◽  
Bolivian Lowlands

Abstract. This study provides an inventory of geomorphological landforms in Eastern Bolivia at different spatial scales. Landforms and associated processes are interpreted and discussed regarding landscape evolution and paleoclimatic significance. Thereby, preliminary conclusions about past climate changes and the geomorphic evolution in Eastern Bolivia can be provided. Fluvial and aeolian processes are presently restricted to a few locations in the study area. A much more active landscape has been inferred from large-scale Channel shifts and extensive paleodune Systems. Mobilization. transport and deposition of Sediments are thought to be the result of climatic conditions drier than today. However. there are also indications of formerly wetter conditions such as fluvial erosion and paleolake basins. In conclusion, the documentation and interpretation of the manifold landforms has shown to contain a considerable amount of paleoecological information, which might serve as the base for further paleoclimatic research in the central part of tropical South America.

Topographic disequilibrium, landscape dynamics and active tectonics: an example from the Bhutan Himalayas

2021 ◽  
Author(s):  
Martine Simoes ◽  
Timothée Sassolas-Serrayet ◽  
Rodolphe Cattin ◽  
Romain Le Roux-Mallouf ◽  
Matthieu Ferry ◽  
...  
Keyword(s):  
Spatial Organization ◽  
Spatial Scales ◽  
Active Tectonics ◽  
Recent Change ◽  
Climatic Conditions ◽  
Landscape Dynamics ◽  
Drainage Basins ◽  
Equilibrium Conditions ◽  
Longitudinal Band ◽  
Active Tectonic

<p>The quantification of active tectonics from geomorphological and morphometric approaches most often implies that erosion and tectonics have reached a certain balance. Such equilibrium conditions may however be seldom found in nature, in particular because drainage basins may be quite dynamic even though tectonic and climatic conditions remain constant. Here, we document this drainage dynamics from the particular case example of the Bhutan Himalayas. Evidence for out-of-equilibrium morphologies have for long been noticed in Bhutan, from major (> 1 km high) river knickpoints and from the existence of high-altitude low-relief regions within the mountain hinterland. These peculiar morphologies were generally interpreted as representing a recent change in climatic and/or tectonic conditions. To further characterize these morphologies and their dynamics, and from there discuss their origin and meaning, we perform field observations and a detailed quantitative morphometric analysis using Chi plots and Gilbert metrics of drainages over various spatial scales, from major Himalayan rivers to local streams draining the low-relief regions. We first find that the river network is highly dynamic and unstable. Our results emphasize that the morphology of Bhutan does not result from a general wave of incision propagating upstream, as expected from most previous interpretations. Also, the specific spatial organization in which all major knickpoints and low-relief regions are located along a longitudinal band in the Bhutan hinterland, whatever their spatial scale and the dimensions of the associated drainage basins, calls for a common local supporting mechanism most probably related to active tectonic uplift. Our results emphasize the need for a precise documentation of landscape dynamics and disequilibrium over various spatial scales as a first-order step in morpho-tectonic studies of active landscapes.</p>

scholarly journals Surface predictor of overturning circulation and heat content change in the subpolar North Atlantic

Ocean Science ◽  
2019 ◽  
Vol 15 (3) ◽  
pp. 809-817 ◽  
Author(s):  
Damien G. Desbruyères ◽  
Herlé Mercier ◽  
Guillaume Maze ◽  
Nathalie Daniault
Keyword(s):  
North Atlantic ◽  
Spatial Scales ◽  
Low Frequency ◽  
Heat Content ◽  
Climatic Conditions ◽  
Meridional Overturning Circulation ◽  
Overturning Circulation ◽  
The North ◽  
Wide Range ◽  
Key Aspects

Abstract. The Atlantic Meridional Overturning Circulation (AMOC) impacts ocean and atmosphere temperatures on a wide range of temporal and spatial scales. Here we use observational datasets to validate model-based inferences on the usefulness of thermodynamics theory in reconstructing AMOC variability at low frequency, and further build on this reconstruction to provide prediction of the near-future (2019–2022) North Atlantic state. An easily observed surface quantity – the rate of warm to cold transformation of water masses at high latitudes – is found to lead the observed AMOC at 45∘ N by 5–6 years and to drive its 1993–2010 decline and its ongoing recovery, with suggestive prediction of extreme intensities for the early 2020s. We further demonstrate that AMOC variability drove a bi-decadal warming-to-cooling reversal in the subpolar North Atlantic before triggering a recent return to warming conditions that should prevail at least until 2021. Overall, this mechanistic approach of AMOC variability and its impact on ocean temperature brings new key aspects for understanding and predicting climatic conditions in the North Atlantic and beyond.

scholarly journals Scale-dependent environmental filtering of ground-dwelling predators in winter wheat and adjacent set-aside areas in Hungary

2020 ◽  
Vol 24 (5) ◽  
pp. 751-763
Author(s):  
Jana Růžičková ◽  
Ferenc Kádár ◽  
Ottó Szalkovszki ◽  
Anikó Kovács-Hostyánszki ◽  
András Báldi ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Natural Enemies ◽  
Spatial Scales ◽  
Habitat Type ◽  
Environmental Filtering ◽  
Landscape Scale ◽  
Dispersal Ability ◽  
Field Scale ◽  
Wheat Field ◽  
Activity Density

Abstract Agricultural intensification may act as an environmental filter shaping invertebrate assemblages at multiple spatial scales. However, it is not fully understood which scale is the most influential. Therefore, we utilized a hierarchical approach to examine the effect of local management (inorganic fertilization and soil properties; within-field scale), habitat type (winter wheat field and set-aside field; between-field scale) and landscape complexity (landscape scale) on assemblage structure and functional diversity of two important groups of natural enemies, carabids and spiders, in a cultivated lowland landscape in Hungary. Environmental filtering affected natural enemies at different spatial scales; likely as a result of enemies’ different dispersal ability and sensitivity to fertilizer use. Carabids were strongly affected at the within-field scale: positively by soil pH, negatively by soil organic matter and fertilization. At the between-field scale, carabids had higher activity density in the set-aside fields than in the winter wheat fields and simple landscapes enhanced carabids diversity, species richness and activity density at the landscape scale. Spiders were more abundant and species-rich in the set-aside fields than in the winter wheat fields. Although highly mobile (macropterous) carabids might disperse to arable crops from greater distances, while spiders possibly depended more on the proximity of set-aside fields, the winter wheat fields (where pest control should be delivered) were utilized mostly by common agrobiont species. Increasing crop heterogeneity within arable fields could be a potential option to increase the diversity of carabids and spiders in the studied region.

A comparison of targeted and systematic fire-scar sampling for estimating historical fire frequency in south-western ponderosa pine forests

2013 ◽  
Vol 22 (8) ◽  
pp. 1021 ◽  
Author(s):  
Calvin A. Farris ◽  
Christopher H. Baisan ◽  
Donald A. Falk ◽  
Megan L. Van Horne ◽  
Peter Z. Fulé ◽  
...  
Keyword(s):  
Ponderosa Pine ◽  
Fire History ◽  
Spatial Scales ◽  
Fire Frequency ◽  
Landscape Scale ◽  
Pine Forests ◽  
Ponderosa Pine Forests ◽  
Fire Scar ◽  
Targeted Sampling ◽  
Statistical Measures

Fire history researchers employ various forms of search-based sampling to target specimens that contain visible evidence of well preserved fire scars. Targeted sampling is considered to be the most efficient way to increase the completeness and length of the fire-scar record, but the accuracy of this method for estimating landscape-scale fire frequency parameters compared with probabilistic (i.e. systematic and random) sampling is poorly understood. In this study we compared metrics of temporal and spatial fire occurrence reconstructed independently from targeted and probabilistic fire-scar sampling to identify potential differences in parameter estimation in south-western ponderosa pine forests. Data were analysed for three case studies spanning a broad geographic range of ponderosa pine ecosystems across the US Southwest at multiple spatial scales: Centennial Forest in northern Arizona (100ha); Monument Canyon Research Natural Area (RNA) in central New Mexico (256ha); and Mica Mountain in southern Arizona (2780ha). We found that the percentage of available samples that recorded individual fire years (i.e. fire-scar synchrony) was correlated strongly between targeted and probabilistic datasets at all three study areas (r=0.85, 0.96 and 0.91 respectively). These strong positive correlations resulted predictably in similar estimates of commonly used statistical measures of fire frequency and cumulative area burned, including Mean Fire Return Interval (MFI) and Natural Fire Rotation (NFR). Consistent with theoretical expectations, targeted fire-scar sampling resulted in greater overall sampling efficiency and lower rates of sample attrition. Our findings demonstrate that targeted sampling in these systems can produce accurate estimates of landscape-scale fire frequency parameters relative to intensive probabilistic sampling.

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