scholarly journals Myco- and photobiont associations in crustose lichens in the McMurdo Dry Valleys (Antarctica) reveal high differentiation along an elevational gradient

2019 ◽  
Author(s):  
Monika Wagner ◽  
Arne C. Bathke ◽  
Craig Cary ◽  
Robert R. Junker ◽  
Wolfgang Trutschnig ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Water Availability ◽  
Abiotic Factors ◽  
Distribution Patterns ◽  
Elevational Gradient ◽  
Mcmurdo Dry Valleys ◽  
Bipartite Network ◽  
Dry Valleys ◽  
Climate Conditions ◽  
Crustose Lichens

AbstractThe climate conditions of the McMurdo Dry Valleys (78° S) are characterized by low temperatures and low precipitation. The annual temperatures at the valley bottoms have a mean range from −30 °C to −15 °C and decrease with elevation. Precipitation occurs mostly in form of snow (3-50 mm a−1 water equivalent) and, liquid water is rare across much of the landscape for most of the year and represents the primary limitation to biological activity. Snow delivered off the polar plateau by drainage winds, dew and humidity provided by clouds and fog are important water sources for rock inhibiting crustose lichens. In addition, the combination of the extremely low humidity and drying caused by foehn winds, confined to lower areas of the valleys, with colder and moister air at higher altitudes creates a strongly improving water availability gradient with elevation.We investigated the diversity and interaction specificity of myco-/photobiont associations of a total of 232 crustose lichen specimens, collected along an elevational gradient (171-959 m a.s.l.) within the McMurdo Dry Valleys with regard to the spatial distribution caused by climatological and geographical factors. For the identification of the mycobiont and photobiont species three markers each were amplified (nrITS, mtSSU, RPB1 and nrITS, psbJ-L, COX2, respectivley). Elevation, associated with a water availability gradient, turned out to be the key factor explaining most of the distribution patterns of the mycobionts. Pairwise comparisons showed Lecidea cancriformis and Rhizoplaca macleanii to be significantly more common at higher, and Carbonea vorticosa and Lecidea polypycnidophora at lower, elevations. Lichen photobionts were dominated by the globally distributed Trebouxia OTU, Tr_A02 which occurred at all habitats. Network specialization resulting from mycobiont-photobiont bipartite network structure varied with elevation and associated abiotic factors.Along an elevational gradient, the spatial distribution, diversity and genetic variability of the lichen symbionts appear to be mainly influenced by improved water relations at higher altitudes.

scholarly journals Myco- and photobiont associations in crustose lichens in the McMurdo Dry Valleys (Antarctica) reveal high differentiation along an elevational gradient

Polar Biology ◽  
2020 ◽  
Vol 43 (12) ◽  
pp. 1967-1983
Author(s):  
Monika Wagner ◽  
Arne C. Bathke ◽  
S. Craig Cary ◽  
T. G. Allan Green ◽  
Robert R. Junker ◽  
...  
Keyword(s):  
Abiotic Factors ◽  
Distribution Patterns ◽  
Elevational Gradient ◽  
Mcmurdo Dry Valleys ◽  
Bipartite Network ◽  
Dry Valleys ◽  
Continental Antarctica ◽  
Key Factor ◽  
Crustose Lichens ◽  
Globally Distributed

AbstractClimatically extreme regions such as the polar deserts of the McMurdo Dry Valleys (78° S) in Continental Antarctica are key areas for a better understanding of changes in ecosystems. Therefore, it is particularly important to analyze and communicate current patterns of biodiversity in these sensitive areas, where precipitation mostly occurs in form of snow and liquid water is rare. Humidity provided by dew, clouds, and fog are the main water sources, especially for rock-dwelling crustose lichens as one of the most common vegetation-forming organisms. We investigated the diversity and interaction specificity of myco-/photobiont associations of 232 crustose lichen specimens, collected along an elevational gradient (171–959 m a.s.l.) within the McMurdo Dry Valleys. The mycobiont species and photobiont OTUs were identified by using three markers each (nrITS, mtSSU, RPB1, and nrITS, psbJ-L, COX2). Elevation, positively associated with water availability, turned out to be the key factor explaining most of the distribution patterns of the mycobionts. Pairwise comparisons showed Lecidea cancriformis and Rhizoplaca macleanii to be significantly more common at higher elevations and Carbonea vorticosa and Lecidea polypycnidophora at lower elevations. Lichen photobionts were dominated by the globally distributed Trebouxia OTU, Tr_A02 which occurred at all habitats. Network specialization resulting from myco-/photobiont bipartite network structure varied with elevation and associated abiotic factors. Along an elevational gradient, the spatial distribution, diversity, and genetic variability of the lichen symbionts appear to be mainly influenced by improved water relations at higher altitudes.

Deciphering belowground nitrifier assemblages with elevational soil sampling in a subtropical forest ecosystem (Mount Lu, China)

2019 ◽  
Vol 96 (1) ◽  
Author(s):  
Shun Han ◽  
Shuang Tan ◽  
Achen Wang ◽  
Wenli Chen ◽  
Qiaoyun Huang
Keyword(s):  
Forest Ecosystem ◽  
Ammonia Oxidation ◽  
Abiotic Factors ◽  
Distribution Patterns ◽  
Elevational Gradient ◽  
Variance Partitioning ◽  
Subtropical Forest ◽  
Elevational Gradients ◽  
Oxidation Activity ◽  
Soil Variables

ABSTRACT The elevational distribution patterns of microbial functional groups have long been attracting scientific interest. Ammonia-oxidizers (ammonia-oxidizing archaea [AOA] and bacteria [AOB]), complete ammonia oxidation (comammox) Nitrospira and nitrite-oxidizers (e.g. Nitrobacter and Nitrospira) play crucial roles in the nitrogen cycle, yet their activities and abundances in response to elevational gradients in a subtropical forest ecosystem remain unclear. Here, we investigated the distribution of potential functions and abundances of these nitrifiers in forest soils along elevational gradients on Mount Lu, China. Our results showed that AOA and Nitrospira abundance was higher than that of their counterparts. Only AOA, Nitrobacter and comammox Nitrospira abundances followed a hump-backed-model with altitude. Soil potential ammonia-oxidation activity (PAO) and nitrite-oxidation activity (PNO) ranged from 0.003 to 0.084 and 0.34 to 0.53 μg NO2−-N g−1 dry soil h−1, respectively. The biotic (AOA, Nitrobacter, Nitrospira and comammox Nitrospira abundances) and abiotic factors (soil variables) jointly affected PAO, whereas the abiotic factors were mainly responsible for PNO. Variance partitioning analysis showed that contemporary environmental disturbance is the most important driver for the biogeography of nitrifier assemblages. Overall, our findings indicate that forest soil nitrifier assemblages exhibit a biogeographic pattern largely shaped by soil chemistry along an elevational gradient.

scholarly journals Spatial Distribution Patterns of Lantana camara L. Population as Invasive Alien Species In Pringtali Savana Bandealit Resort Meru Betiri National Park

2021 ◽  
Vol 22 (1) ◽  
pp. 19
Author(s):  
Hari Sulistiyowati ◽  
Emitria Rahmawati ◽  
Retno Wimbaningrum
Keyword(s):  
Spatial Distribution ◽  
Distribution Pattern ◽  
Alien Species ◽  
National Park ◽  
Abiotic Factors ◽  
Distribution Patterns ◽  
Lantana Camara ◽  
Percent Cover ◽  
Negative Impacts ◽  
The Individual

Bandealit is one of the resorts in Meru Betiri National Park (MBNP). This area has many endemic floras and faunas affected by the presence of invasive alien spesies plants. These plants tend to give negative impacts on savana ecosystem among them is, Lantana camara L. The distribution of this invasive alien spesies in the savana can be used to provide information about the characteristic of the environment. This study was conducted to investigate the patterns of spatial distribution of invasive alien L. camara population in the Pringtali Resort Bandealit savana region. The characters of plant species morphology was recorded for species name identification and validation. Percent cover of the individual L. camara species was collected within 50 plots (5x5 m2), while each of coordinate species found in the plots was recorded by using GPS (Global Positioning System). Abiotic factors such as temperature, pH, light intensity, and soil moisture were measured within the plots. The location of the data collection is 5,000 m2. The distribution pattern of invasive alien L. camara population was analyzed using ArcGIS and Dispersion Morisita’s Index (Ip). The result showed that 51.7% of L. camara population grew spasially close together (clumped) or overlapped one another based on the ArcGIS. This means that L. camara individuals distributein clumped pattern. While the other individuals (48.3%) grew apart randomly from each other. This distribution pattern showed by Ip value, 0.51 was also clumped or clustered. It can be concluded that the distribution pattern ofinvasive alien species L. camara is clumped because the reproduction of plant was by seeds dispersal or vegetative buds that lived around parental individuals.Keywords: ArcGIS, Lantana camara L., Invasive Foreign Plants, Morisita index, Distribution Pattern.

Landscape-scale soil phosphorus variability in the McMurdo Dry Valleys

2017 ◽  
Vol 29 (3) ◽  
pp. 252-263 ◽  
Author(s):  
Ruth C. Heindel ◽  
Angela M. Spickard ◽  
Ross A. Virginia
Keyword(s):  
Nutrient Cycling ◽  
Soil Texture ◽  
Water Availability ◽  
Aquatic Ecosystems ◽  
Soil Phosphorus ◽  
Parent Material ◽  
Mineral Weathering ◽  
Mcmurdo Dry Valleys ◽  
Dry Valleys ◽  
Extractable Phosphorus

AbstractThe predicted increase in liquid water availability in the McMurdo Dry Valleys (MDV), Antarctica, may have profound consequences for nutrient cycling in soil and aquatic ecosystems. Our ability to predict future changes relies on our understanding of current nutrient cycling processes. Multiple hypotheses exist to explain the variability in soil phosphorus content and availability found throughout the MDV region. We analysed 146 surface soil samples from the MDV to determine the relative importance of parent material, landscape age, soil chemistry and texture, and topography on two biologically relevant phosphorus pools, HCl- and NaHCO3-extractable phosphorus. While HCl-extractable phosphorus is highly predicted by parent material, NaHCO3-extractable phosphorus is unrelated to parent material but is significantly correlated with soil conductivity, soil texture and topography. Neither measure of soil phosphorus was related to landscape age across a gradient of ~20 000 to 1 500 000 years. Glacial history has played an important role in the availability of soil phosphorus by shaping patterns of soil texture and parent material. With a predicted increase in water availability, the rate of mineral weathering may increase, releasing more HCl-extractable phosphorus into soil and aquatic ecosystems.

Factors influencing spatial distribution and growth of juvenile lake sturgeon (Acipenser fulvescens)

2015 ◽  
Vol 93 (11) ◽  
pp. 823-831 ◽  
Author(s):  
Cameron C. Barth ◽  
W. Gary Anderson
Keyword(s):  
Spatial Distribution ◽  
Relative Abundance ◽  
Condition Factor ◽  
Abiotic Factors ◽  
Distribution Patterns ◽  
Lake Sturgeon ◽  
Conservation Strategies ◽  
Acipenser Fulvescens ◽  
Catch Per Unit Effort ◽  
Fourth Section

Understanding biotic and abiotic factors that influence spatial distribution patterns, condition factor, and growth of lotic fish species within river impoundments is essential for the development of effective management and conservation strategies. This study aimed to compare relative abundance, condition factor, and growth rate of juvenile lake sturgeon (Acipenser fulvescens Rafinesque, 1817) among eight sections of a 41 km long impoundment of the Winnipeg River, Manitoba, Canada. Relative abundance of juvenile lake sturgeon, as measured by catch per unit effort (CPUE), was 3–6 times greater in the two farthest upstream sections when compared with the five farthest downstream sections. Growth in length was slowest for individuals captured in the two farthest upstream sections, moderate in the third section, and highest in the fourth section, with individuals from the fourth section attaining lengths approximately double those from the two farthest upstream sections by age 6. Condition factor varied among sections of the impoundment in a pattern similar to that observed for growth. Given similarities in many environmental factors such as water temperature and water chemistry among sections of this study area, our results provide important insight into how abiotic and biotic factors, combined with behavioural characteristics of this species, may influence distribution patterns and growth of juvenile lake sturgeon within river impoundments.

Diversity and spatial distribution of autotrophic communities within and between ice-covered Antarctic lakes (McMurdo Dry Valleys)

2015 ◽  
Vol 60 (3) ◽  
pp. 977-991 ◽  
Author(s):  
Jenna M. Dolhi ◽  
Amber G. Teufel ◽  
Weidong Kong ◽  
Rachael M. Morgan-Kiss
Keyword(s):  
Spatial Distribution ◽  
Mcmurdo Dry Valleys ◽  
Dry Valleys ◽  
Antarctic Lakes

Large-scale mapping of the catenas vegetation in Subarctic tundra

1995 ◽  
pp. 3-21
Author(s):  
S. S. Kholod
Keyword(s):  
Spatial Distribution ◽  
Vegetation Cover ◽  
Large Scale ◽  
Block Diagram ◽  
Abiotic Factors ◽  
Ecological Factors ◽  
Spatial Arrangement ◽  
Geological Time ◽  
Ecological Barriers ◽  
Functional Zones

One of the most difficult tasks in large-scale vegetation mapping is the clarification of mechanisms of the internal integration of vegetation cover territorial units. Traditional way of searching such mechanisms is the study of ecological factors controlling the space heterogeneity of vegetation cover. In essence, this is autecological analysis of vegetation. We propose another way of searching the mechanisms of territorial integration of vegetation. It is connected with intracoenotic interrelation, in particular, with the changing role of edificator synusium in a community along the altitudinal gradient. This way of searching is illustrated in the model-plot in subarctic tundra of Central Chukotka. Our further suggestion concerns the way of depicting these mechanisms on large-scale vegetation map. As a model object we chose the catena, that is the landscape formation including all geomorphjc positions of a slope, joint by the process of moving the material down the slope. The process of peneplanation of a mountain system for a long geological time favours to the levelling the lower (accumulative) parts of slopes. The colonization of these parts of the slope by the vegetation variants, corresponding to the lowest part of catena is the result of peneplanation. Vegetation of this part of catena makes a certain biogeocoenotic work which is the levelling of the small infralandscape limits and of the boundaries in vegetation cover. This process we name as the continualization on catena. In this process the variants of vegetation in the lower part of catena are being broken into separate synusiums. This is the process of decumbation of layers described by V. B. Sochava. Up to the slope the edificator power of the shrub synusiums sharply decreases. Moss and herb synusium have "to seek" the habitats similar to those under the shrub canopy. The competition between the synusium arises resulting in arrangement of a certain spatial assemblage of vegetation cover elements. In such assemblage the position of each element is determined by both biotic (interrelation with other coenotic elements) and abiotic (presence of appropriate habitats) factors. Taking into account the biogeocoenotic character of the process of continualization on catena we name such spatial assemblage an exolutionary-biogeocoenotic series. The space within each evolutionary-biogeocoenotic series is divided by ecological barriers into some functional zones. In each of the such zones the struggle between synusiums has its individual expression and direction. In the start zone of catena (extensive pediment) the interrelations of synusiums and layers control the mutual spatial arrangement of these elements at the largest extent. Here, as a rule, there predominate edificator synusiums of low and dwarfshrubs. In the first order limit zone (the bend of pediment to the above part of the slope) one-species herb and moss synusiums, oftenly substituting each other in similar habitats, get prevalence. In the zone of active colonization of slope (denudation slope) the coenotic factor has the least role in the spatial distribution of the vegetation cover elements. In particular, phytocoenotic interactions take place only within separate microcoenoses of herbs, mosses and lichens. In the zone of the attenuation of continualization process (the upper most parts of slope, crests) phytocoenotic interactions are almost absent and the spatial distribution of vegetation cover elements depends exclusively on the abiotic factors. The principal scheme of the distribution of vegetation cover elements and the disposition of functional zones on catena are shown on block-diagram (fig. 1).

Modeling spatial distribution of the unionid mussels and the core-satellite hypothesis

1998 ◽  
Vol 38 (7) ◽  
pp. 73-79 ◽  
Author(s):  
Hooi-Ling Lee ◽  
Donald DeAngelis ◽  
Hock-Lye Koh
Keyword(s):  
Spatial Distribution ◽  
Life Cycle ◽  
Success Rate ◽  
Distribution Patterns ◽  
Fish Host ◽  
Limited Movement ◽  
Unionid Mussels ◽  
Species Characteristics ◽  
Major Factors ◽  
Fish Hosts

This paper discusses the spatial distribution patterns of the various species of the Unionid mussels as functions of their respective life-cycle characteristics. Computer simulations identify two life-cycle characteristics as major factors governing the abundance of a species, namely the movement range of their fish hosts and the success rate of the parasitic larval glochidia in finding fish hosts. Core mussels species have fish hosts with large movement range to disperse the parasitic larval glochidia to achieve high levels of abundance. Species associated with fish host of limited movement range require high success rate of finding fish host to achieve at least an intermediate level of abundance. Species with low success rate of finding fish hosts coupled with fish hosts having limited movement range exhibit satellite species characteristics, namely rare in numbers and sparse in distributions.

Sign in / Sign up

Export Citation Format

Share Document