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Understanding the composition of soil organic matter (SoM) is vital to our understanding of how soils form, evolve and respond to external stimuli. the shear complexity of SoM, an inseparable mixture of thousands of compounds hinders the determination of structure-function relationships required to explore these processes on a molecular level. Litter bags and soil hot water extracts (HWe) have frequently been used to study the transformation of labile SoM, however these are still too complex to examine beyond compound classes. in this work, a much simpler mixture, HWe buried green tea, was investigated by nuclear Magnetic Resonance (nMR) spectroscopy and fourier transform ion cyclotron Resonance Mass Spectrometry (ft-icR-MS), as a proxy for labile SoM. changes induced by the burial over 90 days in a grassland, woodland and two peatland sites, one damaged by drainage and one undergoing restoration by drain-blocking, were analysed. Major differences between the extracts were observed on the level of compound classes, molecular formulae and specific molecules. The causes of these differences are discussed with reference to abiotic and biotic processes. Despite the vastly different detection limits of NMR and MS, chemometric analysis of the data yielded identical separation of the samples. These findings provide a basis for the molecular level interrogation of labile SOM and c-cycling processes in soils. Earth's soils store a greater amount of C than both the vegetation and atmosphere combined and thus play a crucial role in the global C cycle 1. The accumulation of C is largely the result of restricted decomposition rates, which are ecosystem dependent. Three major causes for these restrictions include climate (temperature and moisture), substrate quality (chemical and physical characteristics), and the composition, abundance and activity of the soil biotia 2,3. Soil decomposition has historically been studied using litter bags, which consist of plant material of known mass enclosed in a screened container 4,5. A variety of different litter bag compositions and protocols have been used over the years, which makes a cross-study comparison practically impossible 6,7. More recently, a standardized method using green and rooibos Lipton tea bags has emerged 8 , which involves burying pairs of pre-weighed green and rooibos tea bags 15 cm apart to a depth of 8 cm. After 90 days, the tea bags are collected, dried and weighed. Using the fact that the rooibos tea decomposes slower than the green tea permits the so-called stabilization factor, S and decomposition rate, k, to be calculated from the determined weight losses. These two variables constitute the Tea Bag Index (TBI) which has been measured for different soils worldwide in order to define the relationships between soil types, decomposition rates and environmental factors 6,8-10. The tea bag decomposition rates, k, have been shown to positively correlate with those of local litter and respond in similar ways to biotic factors 7,9,11. On a molecular level soil litter d...

Despite great scientific and industrial interest in waterproof cellulosic paper, its real world application is hindered by complicated and costly fabrication processes, limitations in scale-up production, and use of organic solvents. Furthermore, simultaneously achieving nonwetting properties and printability on paper surfaces still remains a technical and chemical challenge. Herein, we demonstrate a nonsolvent strategy for scalable and fast fabrication of waterproofing paper through in situ surface engineering with polysilsesquioxane nanorods (PSNRs). Excellent superhydrophobicity is attained on the functionalized paper surface with a water contact angle greater than 160°. Notably, the engineered paper features outstanding printability and writability, as well as greatly enhanced strength and integrity upon prolonged exposure to water (tensile strength ≈ 9.0 MPa). Additionally, the PSNRs concurrently armor paper-based printed items and artwork with waterproofing, self-cleaning, and antimicrobial functionalities without compromising their appearance, readability, and mechanical properties. We also demonstrate that the engineered paper holds the additional advantages of easy processing, low cost, and mechanochemical robustness, which makes it particularly promising for real world applications.