The solid electrolyte interphase (SEI) that forms on Li-ion battery anodes is critical to their long-term performance, however observing SEI formation processes at the buried electrode-electrolyte interface is a significant challenge. Here we show that operando soft X-ray absorption spectroscopy in total electron yield mode can resolve the chemical evolution of the SEI during electrochemical formation in a Li-ion cell, with nm-scale interface sensitivity. O, F, and Si K-edge spectra, acquired as a function of potential, reveal when key reactions occur on high-capacity amorphous Si anodes cycled with and without fluoroethylene carbonate (FEC). The sequential formation of inorganic (LiF) and organic (-(C=O)O-) components is thereby revealed, and results in layering of the SEI. The addition of FEC leads to SEI formation at higher potentials which is implicated in the rapid healing of SEI defects and the improved cycling performance observed. Operando TEY-XAS offers new insights into the formation mechanisms of electrode-electrolyte interphases and their stability for a wide variety of electrode materials and electrolyte formulations.

The density, biomass, species richness and composition of birds in plots in two Mountain Fynbos plantspecies assemblages (Tall Mixed Fynbos and Restionaceous Tussock Marsh), infested with alien woody plants (mainly Australian Acacia spp.) at the Cape of Good Hope Nature Reserve, South Africa, were compared with those of uninfested plots. The relative density of frugivorous and granivorous birds tended to increase, but total bird density did not change significantly with increasing density of Acacia cyclops in Tall Mixed Fynbos. However, the density of nectarivorous birds decreased with increasing A. cyclops infestation as a result of the elimination of their food plants (proteaceous and ericaceous shrubs). Thus, alien woody plants have the capacity to disrupt the putative avian nectarivore-indigenous plant pollination relationship. Dense infestations of mixed alien species in Restionaceous Tussock Marsh supported fewer nectarivorous birds, but more granivores and insectivores than did uninfested vegetation. Moreover, bird species more typical of woodland and thicket (and absent from uninfested fynbos vegetation), notably large granivores, were found in dense mixed-alien infestations of this plant-species assemblage. Die digtheid, biomassa, spesierykheid en-samestelling van voels in persele in twee bergfynbosplantspesiegroepe (Hoe Gemengde Fynbos en Restioonagtige Polvleij vervuil met uitheemse houtagtige plante (hoofsaaklik Australiese Acacia spp.), in die Kaap die Goeie Hoop-Natuurreservaat, Suid-Afrika, is vergelyk met die van onvervuilde persele. Die relatiewe digthede van vrugte-en saadvretende voels het effens toegeneem, alhoewel totale voeldigtheid nie betekenisvol deur toenemende Acacia cyc/ops-digthede in Hoe Bergfynbos be"invloed is nie. Nietemin het digthede van nektarvretende voels afgeneem met toenemende A. cyc/opsvervuiling as gevolg van die verdringing van hul voedselplante (protea-en erika-agtige struike). Gevolglik het uitheemse houtagtige plantvervuilings die vermoe om die veronderstelde nektarvretende voels-inheemse plant-bestuiwingsverhouding te ontwrig. Digte gemengde uitheemse spesievervuilings in Restioonagtige Polvleie het minder nektarvretende voels, maar meer saad-en insektevretende voels as onvervuilde plantegroei, onderhou. Verder is voelspesies, wat meer tipies van boswereld en digbos is (en afwesig is in onvervuilde fynbosplantegroei), vernaamlik groat saadvreters, in digte gemengde-uitheemse vervuilings van hierdie plantspesiegroep gevind.

FRASER, M. W. 1989. Short-term responses of birds to fire in old Mountain Fynbos. Ostrich: 60: 172-182. Observations of birds were made from six weeks before until one year after a fire in 28-year-old Mountain Fynbos vegetation near Stellenbosch, Cape Province, South Africa. No fire attendance by birds was observed, in contrast to observations made at fires in other southern African vegetation types. Bird species composition in the study site as a whole was virtually unchanged after the fire. With the exception of the density of nectarivorous birds (which decreased), variation in the bird densities of study plots in six vegetation structural formations was considered to be as much seasonal as fire-related.

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