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Plant functional traits provide a valuable tool to improve our understanding of ecological processes at a range of scales. Previous handbooks on plant functional traits have highlighted the importance of standardising measurements of traits to improve our understanding of ecological and evolutionary processes. In open ecosystems (i.e. grasslands, savannas, open woodlands and shrublands), traits related to disturbance (e.g. herbivory, drought, and fire) play a central role in explaining species performance and distributions and are the focus of this handbook. We provide brief descriptions of 34 traits and list important environmental filters and their relevance, provide detailed sampling methodologies and outline potential pitfalls for each trait. We have grouped traits according to plant functional type (grasses, forbs and woody plants) and, because demographic stages may experience different selective pressures, we have separated traits according to the different plant life stages (seedlings saplings and adults). We have attempted to not include traits that have been covered in previous handbooks except for where updates or additional information was considered beneficial.

The mineral goethite (a-FeOOH) has previously been investigated as a thermodynamically stable repository for many potentially toxic metals (e.g., Cd, Pb, Cu). The substitution of uranium (U as uranyl, UO22+) for Fe, however, has been studied sparingly, and conclusive uranium incorporation into the goethite structure has been obscured by formation of ploymineralic Fe systems that all appeared involved in U's sequestration. In this study, we investigated the formation of goethite from FeCl2 in the presence of seven nominal uranyl concentrations (0.2-4mole percent, U/(U+Fe)×100) and characterised the solids using quantitative X-ray diffraction (QXRD), X-ray absorption fine structure (XAFS) spectroscopy at the U LIII edge (17,166eV), diffuse reflectance infrared Fourier Transform (DRIFT) spectrometry and congruency of acid dissolution. Our findings show that U does indeed, however sparingly, incorporate into the goethite structure. The unit cell volume, ascertained from Rietveld models of XRD patterns, increased linearly as a function of U content, which could be ascribed to a linear increase of the unit cell length a and c. The highest U-for-Fe substitution was 0.48mole percent, however, most U-containing goethite samples showed substitution levels around 0.2mole percent, which was in good agreement with previous findings. DRIFT spectra showed a shift of the symmetric Fe-O and asymmetric Fe-OH stretch modes (t-O and t-OH bands, respectively) to lower frequency, which by Hooks analogy, can only occur if a heavier atom substitutes for Fe, i.e., U. The congruency of acid dissolution results showed that fractional U release was greater than the corresponding fractional Fe release into solution, suggesting that U was overall more soluble. In two of the synthates, however, (initial U mole percent of 2 and 4), the dissolution was congruent. XAFS data collected on a selected subset of samples showed the disappearance of the uranyl moiety with higher levels of U incorporation a

Quantitative and/or qualitative characterising of physical and chemical properties at a range of scales can be used to interpret ore genesis, assess and model the chemistry and variation of ore feed, identify problematic gangue or refractory minerals, determine liberation and size distribution, or evaluate the efficiency of an extraction technique. Three critical factors are correct sample selection, suitable preparation and the use of an appropriate characterisation tool that gives adequate resolution. Certainty of interpretation can be improved by using complementary analytical techniques to acquire parallel data sets. In the case of a low-grade, fine-grained uranium ore, to re-classify sub-economic resources as extractable reserves required a focus on optimising ore recovery and metal extraction; feed and leached samples were investigated using multiple methods including synchrotron-based studies, field emission-gun electron-probe microanalysis and QEMScan., Quantitative and/or qualitative characterising of physical and chemical properties at a range of scales can be used to interpret ore genesis, assess and model the chemistry and variation of ore feed, identify problematic gangue or refractory minerals, determine liberation and size distribution, or evaluate the efficiency of an extraction technique. Three critical factors are correct sample selection, suitable preparation and the use of an appropriate characterisation tool that gives adequate resolution. Certainty of interpretation can be improved by using complementary analytical techniques to acquire parallel data sets. In the case of a low-grade, fine-grained uranium ore, to re-classify sub-economic resources as extractable reserves required a focus on optimising ore recovery and metal extraction; feed and leached samples were investigated using multiple methods including synchrotron-based studies, field emission-gun electron-probe microanalysis and QEMScan.

Dipositive cation substitution in sulfate minerals has been a topic of investigation both experimentally and computationally. Here the possibility of tripositive cation substitution with accompanying vacancy formation is considered, specifically lanthanum ion substitution in barium sulfate. Experimentally, the lanthanum ions impact "bulk" crystallization in a way that is best explained by considering the solution phase ion-pair interactions. However, morphological results suggest that lanthanum ions do more than impact the free sulfate levels. Atomic force microscopy results showed that both lanthanum and calcium ions are strong inhibitors of barite growth. X-ray diffraction on bulk samples showed that lanthanum ions do indeed incorporate, as determined by lattice parameter changes. Finally, computational modeling suggests that while calcium incorporation is more energetically favorable, lanthanum ions prefer to substitute on the surface more so than calcium ions.

Slurry flow properties are important for plant design and operation and the use of a simple vane test for shear yield stress determination can be time-consuming and require large amounts of sample material. Tests were carried out on samples from a calcrete-hosted U ore to determine whether the compressive yield stress may be used as an alternative to shear yield stress to obtain a relative indication of sample rheological behaviour. Qualitative comparison of the relative shear and compressive yield stress for 21 samples showed good agreement, with the exception of 2 samples for which the relative trend varied significantly. The squared correlation coefficient between the compressive and shear tests was 0.6 and increased to 0.75 when the two outliers were removed, indicating that a compressive centrifuge test may allow for more rapid yield stress determination. In relation to sample mineralogy quartz and dolomite had a positive effect on rheology and smectite had a negative effect on yield stress. Larger particles gave improved behaviour, but the correlation with particle size was less than that observed for smectite content., Slurry flow properties are important for plant design and operation and the use of a simple vane test for shear yield stress determination can be time-consuming and require large amounts of sample material. Tests were carried out on samples from a calcrete-hosted U ore to determine whether the compressive yield stress may be used as an alternative to shear yield stress to obtain a relative indication of sample rheological behaviour. Qualitative comparison of the relative shear and compressive yield stress for 21 samples showed good agreement, with the exception of 2 samples for which the relative trend varied significantly. The squared correlation coefficient between the compressive and shear tests was 0.6 and increased to 0.75 when the two outliers were removed, indicating that a compressive centrifuge test may allow for more rapid yield stress determination. In relation to sample mineralogy quartz and dolomite had a positive effect on rheology and smectite had a negative effect on yield stress. Larger particles gave improved behaviour, but the correlation with particle size was less than that observed for smectite content.