Publications by authors named "Orpheus M Butler"

Climate change is exacerbating a global decline in biodiversity. Numerous observational studies link rising temperatures to declining biological abundance, richness and diversity in terrestrial ecosystems, yet few studies have considered the highly diverse and functionally significant communities of tropical forest soil and leaf litter fauna. Here, we report major declines in the order-level richness and diversity of soil and leaf litter fauna following three years of experimental whole-profile soil warming in a tropical forest.

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Many microorganisms synthesise carbon (C)-rich compounds under resource deprivation. Such compounds likely serve as intracellular C-storage pools that sustain the activities of microorganisms growing on stoichiometrically imbalanced substrates, making them potentially vital to the function of ecosystems on infertile soils. We examined the dynamics and drivers of three putative C-storage compounds (neutral lipid fatty acids [NLFAs], polyhydroxybutyrate [PHB], and trehalose) across a natural gradient of soil fertility in eastern Australia.

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Decadal-scale increases in fire frequency have the potential to deplete ecosystems of essential nutrients and consequently impede nutrient-limited biological processes via stoichiometric imbalance. Decomposition, a fundamental ecosystem function and strong driver of future fire occurrence, is highly sensitive to nutrient availability and is, therefore, particularly important in this context. Here we show that 40 yr of quadrennial (4yB) and biennial (2yB) prescribed burning result in severely P- and N-depleted litter stoichiometry, respectively, relative to fire exclusion.

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The construction and operation of the Three Gorges Reservoir (TGR), the largest hydropower dam in the world, has had significant consequences for the hydrology of riparian zones along the Yangtze river. Little is known about how such changes in hydrology might affect the levels of nutrients and organic matter (OM) in riparian soils. We conducted a nine-year study on the spatio-temporal dynamics and dominant environmental correlates of nutrients and OM in riparian soils along a 600 km section of the Yangtze.

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Riparian ecosystems are particularly prone to heavy metal (HM) contamination, acting as a sink for HMs coming from human activities upstream or on adjacent uplands. An advanced understanding of the spatio-temporal dynamics, environmental drivers and the likely sources of HM contamination in riparian soils will be necessary for the conservation of riparian ecosystems. Thus, we conducted a nine-year study across a 600 km stream gradient along the Yangtze river, which has come under immense pressure in recent years partly due to the establishment of the Three Gorges Dam (TGD), the largest hydropower dam in the world.

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The biogeochemical and stoichiometric signature of vegetation fire may influence post-fire ecosystem characteristics and the evolution of plant 'fire traits'. Phosphorus (P), a potentially limiting nutrient in many fire-prone environments, might be particularly important in this context; however, the effects of fire on P cycling often vary widely. We conducted a global-scale meta-analysis using data from 174 soil studies and 39 litter studies, and found that fire led to significantly higher concentrations of soil mineral P as well as significantly lower soil and litter carbon:P and nitrogen:P ratios.

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Char as a carbon-rich material, can be produced under pyrolytic conditions, wildfires or prescribed burn offs for fire management. The objective of this study was to elucidate mechanistic interactions of copper (Cu) and nickel (Ni) with different chars produced by pyrolysis (green waste, GW; blue-Mallee, BM) and forest fires (fresh-burnt by prescribed fire, FC; aged char produced by wild fire, AC). The pyrolytic chars were more effective sorbents of Cu (∼11 times) and Ni (∼5 times) compared with the forest fire chars.

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