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Aim: Termites are a crucial group of macroinvertebrates regulating rates of deadwood decomposition across tropical and subtropical regions. When examining global patterns of deadwood decay, termites are treated as a homogenous group. There exist key biogeographical differences in termite distribution. One such clear distinction is the distribution of fungus‐growing termites (FGT, subfamily Macrotermitinae). Considering that climate will have shaped termite distribution and ecosystem processes, we evaluate the roles of termite distribution (presence of FGT) and climate (aridity) on global patterns in deadwood decay. Location: Between 46° N‐43° S and 175° E‐85° W. Time Period: Present (between 2016 and 2021). Major Taxa Studied: Termites (Blattodea: Termitoidae). Methods: We add salient data to an existing global dataset on deadwood decomposition, including new data from five existing sites and seven additional African sites. We analyse a dataset spanning six continents, 16 countries and 102 experimental sites. Firstly, we evaluate climatic differences (mean annual temperature, mean annual precipitation and mean annual aridity) between sites with and without FGT. Secondly, using aridity as a single comparative climate metric between sites that accounts for temperature and precipitation differences, we examine the interaction between FGT and aridity on global patterns of termite deadwood discovery and decay through multivariate logistic and linear regressions. Results: Termite‐driven decay and wood discovery increased with aridity; however, responses differed between FGT and NFGT sites. Wood discovery increased with aridity in FGT sites only, suggesting a greater role of FGT to deadwood decay in arid environments. On average, both termite discovery and decay of deadwood were approximately four times greater in regions with FGT compared with regions without FGT. Main Conclusions: Termite discovery and decay of deadwood is climate dependent, and higher decay may be through greater discovery of deadwood in FGT sites. Inclusion of biogeographical differences in termite distribution could potentially alter current and future global estimates of deadwood turnover. [ABSTRACT FROM AUTHOR]

Termite mounds are keystone structures in African savannas, affecting multiple ecosystem processes. Despite the large size of termite mounds having the potential to modify conditions around them, patterns of mound‐induced ecosystem effects have been assumed to be isotropic, with little attention given to how effects might vary around mounds. We measured soil nitrogen content, grass species composition, and mammalian grazing on and off termite mounds in the four cardinal directions, and across wet and dry seasons at three savanna sites varying in mean annual rainfall in South Africa's Kruger National Park. Evidence of directional effects (anisotropy) on ecosystem properties around termite mounds varied with site. Grass species composition differed between north‐ and south‐facing slopes at the two drier sites where mounds were taller. However, differences in grazing extent and soil nitrogen content around mounds were only present at the intermediate rainfall site where mammalian herbivore biomass was highest, and mounds were of medium height. Our results suggest that termite mound effects display significant variation with direction, but that the emergence of directional effects is context dependent. Our results further suggest that such context‐dependent directional effects can lead to positive feedback loops between termites, abiotic conditions, and mammalian herbivores. [ABSTRACT FROM AUTHOR]

Ordered mesoporous carbons (OMCs) have shown great promise in a variety of applications, including adsorption, energy storage, and catalysis. To elevate their performance further, it is important to introduce additional functionalities into their composition and surface chemistry, as well as to enhance their pore surface area. Recently, a simple method for OMC synthesis is established through leveraging commodity thermoplastic elastomers (TPEs) as precursors. In this system, a sulfonation-induced crosslinking reaction is employed to selectively crosslink the olefinic majority phase of TPEs, enabling its conversion to carbon upon pyrolysis, while decomposing the styrenic minority phase to develop mesopores. Building on this platform approach, this works demonstrates multiple functionalization pathways to modulate pore texture and chemical composition of TPE-derived OMCs, which can allow their further and enhanced use in a variety of applications. This work first shows that chemical activation can significantly enhance the surface area of TPE-derived OMCs, increasing from 485 m2 g−1 to approximately 1250 m2 g−1. Furthermore, the introduction of dopants into crosslinked TPEs facilitates the incorporation of heteroatoms, such as boron, nitrogen, sulfur, and phosphorus into the carbon framework during carbonization. The hydrophilic nature of the crosslinked polymer also enables the incorporation of water-soluble metal nitrates, which can then form metal nanoparticles within the carbon framework upon carbonization. Collectively, this work demonstrates simple and scalable methods to improve the capabilities of TPE-derived OMCs via functionalization, including chemical activation to increase surface area, heteroatom doping, and introducing nanoparticles into the carbon framework. [ABSTRACT FROM AUTHOR]

Hierarchically macro-/mesoporous (HMM) materials generally contain at least two distinct populations of pore sizes with ranges of 2-50 nm and >50 nm; they exhibit promising performance for various applications, such as water remediation and energy storage, due to the combined advantages of high surface area, pore accessibility, and porosity. Conventional synthesis of HMM materials typically utilize multiple templating agents to develop varied sizes of pores, often involving complex processes and the use of relatively expensive precursors with low recourse-efficiency, leading to significant challenges toward scaled production. Therefore, development of a simple approach for HMM materials synthesis is important for facilitating their commercialization and broad use. In this work, we demonstrate a generalizable method for the fabrication of HMM polymers and carbons using immiscible thermoplastic elastomer (TPE) blends, through incorporating a small amount of polystyrene-blockpolyisoprene-block-polystyrene (SIS) within the matrix of polystyrene-block-poly(ethylene-ranbutylene)- block-polystyrene (SEBS), followed by sulfonation-induced crosslinking. During this reaction, the presence of SIS not only leads to the formation of macropores from released gaseous products, but it also facilitates the selective degradation of polystyrene domains to develop ordered mesopores. These porous polymers can then be converted to HMM carbons upon pyrolysis, where ordered nanostructures can be retained. This approach to produce HMM materials can be generalized to different selections of TPE blends with varied precursor identity and molecular weight. Furthermore, we demonstrate that HMM polymers can be employed as sorbents for the efficient removal of heavy metals from aqueous systems, while their derived carbons are efficient for organic pollutant remediation. We believe this work demonstrates a simple and robust approach with great potential for the scaled manufacturing of HMM materials to enable their broad use in practical applications. [ABSTRACT FROM AUTHOR]