Distribution and Floristics of Bryophytes in Soil Crusts in Semi-Arid and Arid Eastern Australia

A total of 56 bryophyte taxa associated with biological soil crusts was collected from 282 sites in semi-arid and arid eastern Australia. The 41 moss taxa and 15 liverwort taxa found were dominated by the families Pottiaceae and Ricciaceae respectively. Bryophytes were present at 224 of the 282 sites, and their distribution varied widely according to different landscapes. The mean number of taxa per site ranged from 8.9 on plains with red earths to 2.1 on active floodplains. The most common bryophytes found in the survey area were Bryum pachytheca, Didymodon torquatus, Gigaspermum repens, Goniomitrium enerve, Desmatodon convolutus, Stonea oleaginosa, Crossidium davidai, Riccia limbata and Riccia lamellosa. In this paper, the distribution of bryophytes in relation to landscape types, and some strategies for surviving in arid environments and their roles in biodiversity and rangeland condition assessment are discussed. Their distribution is compared with other published and unpublished studies from similar areas of Australia.

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Small-scale patterns of abundance of mosses and lichens forming biological soil crusts in two semi-arid gypsum environments

Australian Journal of Botany ◽

10.1071/bt05078 ◽

2006 ◽

Vol 54 (4) ◽

pp. 339 ◽

Cited By ~ 64

Author(s):

I. Martínez ◽

A. Escudero ◽

F. T. Maestre ◽

A. de la Cruz ◽

C. Guerrero ◽

...

Keyword(s):

Biological Soil Crust ◽

Aggregate Stability ◽

Bare Soil ◽

Biological Soil Crusts ◽

Small Scale ◽

Arid Environments ◽

Soil Variables ◽

Constrained Ordination ◽

Soil Crusts ◽

Semi Arid

Despite important advances in the understanding of biological soil crusts and their key role in ecosystem processes in arid and semi-arid environments, little is known about those factors driving the small-scale patterns of abundance and distribution of crust-forming lichens and mosses. We used constrained ordination techniques (RDAs) to test the hypothesis that the spatial patterning of lichens and mosses is related to surface and subsurface soil variables in two semi-arid gypsum environments of Spain. Our results show that the abundance of mosses and lichens forming biological soil crusts was related to a limited set of variables (cover of bare soil and litter, soil respiration, potassium content and aggregate stability). Moreover, they provide some insights into the importance of these variables as drivers of biological soil-crust composition and abundance in semi-arid gypsum environments.

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Maximising trapping efficiency in reptile surveys: the role of seasonality, weather conditions and moon phase on capture success

Wildlife Research ◽

10.1071/wr09157 ◽

2010 ◽

Vol 37 (2) ◽

pp. 104 ◽

Cited By ~ 14

Author(s):

Lisa M. Spence-Bailey ◽

Dale G. Nimmo ◽

Luke T. Kelly ◽

Andrew F. Bennett ◽

Michael F. Clarke

Keyword(s):

Weather Conditions ◽

Trapping Efficiency ◽

Individual Species ◽

Arid Environments ◽

Moon Phase ◽

Mixed Effect ◽

Capture Success ◽

Eastern Australia ◽

Semi Arid ◽

Capture Rates

Context. Designing an appropriate survey protocol requires understanding of how capture rates of target species may be influenced by factors other than on-ground abundance, such as weather conditions or seasonality. This is particularly relevant for ectotherms such as reptiles, as activity can be affected by environmental conditions such as ambient temperature. Aims. The present study examines factors affecting capture success of reptiles in semi-arid environments of southern Australia, and addresses the following two main questions: (1) what is the influence of weather and seasonal factors on capture rates of reptiles, and (2) what are the implications for developing an effective protocol for reptile surveys? Methods. We surveyed reptiles using pitfall traps in spring and summer of 2006/07 and 2007/08 at sites (n = 280) throughout the Murray Mallee region of south-eastern Australia. We used mixed-effect regression models to investigate the influence of seasonal and weather-related variables on species’ capture success. Key results. Total captures of reptiles, and the likelihood of capture of 15 reptile species, increased with rising daily temperature. Greater numbers of individual species were captured during spring than in summer, even though temperatures were cooler. This probably reflects greater levels of activity associated with breeding. Several species were more likely to be captured when maximum or minimum daily temperatures exceeded a certain level (e.g. Lerista labialis, Delma australis, Nephrurus levis). Other factors, such as rainfall and moon phase, also influenced capture success of some species. Conclusions. Surveys for reptiles in semi-arid environments are likely to capture the greatest diversity of species on warm days in late spring months, although surveys on hot days in summer will enhance detection of particular species (e.g. Morethia boulengeri, Varanus gouldii). We recommend trapping during periods with maximum temperatures exceeding 25–30°C and minimum overnight temperatures of 15°C. Finally, trapping during rainfall and full-moon events will maximise chances of encountering species sensitive to these variables (blind snakes and geckoes). Implications. Selecting the most favourable seasonal and weather conditions will help ensure that reptile surveys maximise the likelihood of capturing the greatest diversity of reptiles, while minimising trap-effort required.

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A New Application of Random Forest Algorithm to Estimate Coverage of Moss-Dominated Biological Soil Crusts in Semi-Arid Mu Us Sandy Land, China

Remote Sensing ◽

10.3390/rs11111286 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1286 ◽

Cited By ~ 3

Author(s):

Xiang Chen ◽

Tao Wang ◽

Shulin Liu ◽

Fei Peng ◽

Atsushi Tsunekawa ◽

...

Keyword(s):

Random Forest ◽

Biological Soil Crusts ◽

Data Availability ◽

Sandy Land ◽

Desert Ecosystems ◽

Mu Us Sandy Land ◽

Soil Crusts ◽

Band Combinations ◽

Semi Arid ◽

Sentinel 2

Biological soil crusts (BSCs) play an essential role in desert ecosystems. Knowledge of the distribution and disappearance of BSCs is vital for the management of ecosystems and for desertification researches. However, the major remote sensing approaches used to extract BSCs are multispectral indices, which lack accuracy, and hyperspectral indices, which have lower data availability and require a higher computational effort. This study employs random forest (RF) models to optimize the extraction of BSCs using band combinations similar to the two multispectral BSC indices (Crust Index-CI; Biological Soil Crust Index-BSCI), but covering all possible band combinations. Simulated multispectral datasets resampled from in-situ hyperspectral data were used to extract BSC information. Multispectral datasets (Landsat-8 and Sentinel-2 datasets) were then used to detect BSC coverage in Mu Us Sandy Land, located in northern China, where BSCs dominated by moss are widely distributed. The results show that (i) the spectral curves of moss-dominated BSCs are different from those of other typical land surfaces, (ii) the BSC coverage can be predicted using the simulated multispectral data (mean square error (MSE) < 0.01), (iii) Sentinel-2 satellite datasets with CI-based band combinations provided a reliable RF model for detecting moss-dominated BSCs (10-fold validation, R2 = 0.947; ground validation, R2 = 0.906). In conclusion, application of the RF algorithm to the Sentinel-2 dataset can precisely and effectively map BSCs dominated by moss. This new application can be used as a theoretical basis for detecting BSCs in other arid and semi-arid lands within desert ecosystems.

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Flux balance modeling to predict bacterial survival during pulsed-activity events

Biogeosciences ◽

10.5194/bg-15-2219-2018 ◽

2018 ◽

Vol 15 (7) ◽

pp. 2219-2229 ◽

Cited By ~ 4

Author(s):

Nicholas A. Jose ◽

Rebecca Lau ◽

Tami L. Swenson ◽

Niels Klitgord ◽

Ferran Garcia-Pichel ◽

...

Keyword(s):

Mass Spectroscopy ◽

Compatible Solutes ◽

Soil Microbial Communities ◽

Metabolic Model ◽

Biological Soil Crusts ◽

Arid Environments ◽

Bacterial Survival ◽

Flux Balance ◽

Soil Crusts ◽

Microcoleus Vaginatus

Abstract. Desert biological soil crusts (BSCs) are cyanobacteria-dominated surface soil microbial communities common to plant interspaces in arid environments. The capability to significantly dampen their metabolism allows them to exist for extended periods in a desiccated dormant state that is highly robust to environmental stresses. However, within minutes of wetting, metabolic functions reboot, maximizing activity during infrequent permissive periods. Microcoleus vaginatus, a primary producer within the crust ecosystem and an early colonizer, initiates crust formation by binding particles in the upper layer of soil via exopolysaccharides, making microbial dominated biological soil crusts highly dependent on the viability of this organism. Previous studies have suggested that biopolymers play a central role in the survival of this organism by powering resuscitation, rapidly forming compatible solutes, and fueling metabolic activity in dark, hydrated conditions. To elucidate the mechanism of this phenomenon and provide a basis for future modeling of BSCs, we developed a manually curated, genome-scale metabolic model of Microcoleus vaginatus (iNJ1153). To validate this model, gas chromatography–mass spectroscopy (GC–MS) and liquid chromatography–mass spectroscopy (LC–MS) were used to characterize the rate of biopolymer accumulation and depletion in in hydrated Microcoleus vaginatus under light and dark conditions. Constraint-based flux balance analysis showed agreement between model predictions and experimental reaction fluxes. A significant amount of consumed carbon and light energy is invested into storage molecules glycogen and polyphosphate, while β-polyhydroxybutyrate may function as a secondary resource. Pseudo-steady-state modeling suggests that glycogen, the primary carbon source with the fastest depletion rate, will be exhausted if M. vaginatus experiences dark wetting events 4 times longer than light wetting events.

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