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Botanic gardens unite to prevent species extinctions: the Global Conservation Consortium for Erica. Michael Pirie et al. describe an international project to prevent extinctions of species of Erica, the heaths or heathers. The ‘Global Conservation Consortium for Erica’ is coordinated at the Bergen University Gardens under the umbrella of Botanic Gardens Conservation International (BGCI). The authors describe the challenges of understanding and protecting species rich plant groups where much of the diversity is concentrated in biodiversity hotspots. Around 700 Erica species are only found in South Africa’s Cape Floristic Region. They explain how GCC Erica will address those challenges, including through both ‘in situ’ and ‘ex situ’ conservation.

Poster for Botany2021 meeting: http://www.botanyconference.org/engine/search/643.html Image credits:Top left: Anthony Hitchcock with reintroduced Erica verticillata.Top right: Alex Lansdowne at the Princess Vlei Forum in 2019 http://www.princessvlei.org/events--projects/today-we-are-planting-wolves. Photo by Bridget Pitt.Centre left: Erica propagation at Belvedere Garden, Vienna (image MK/DR).Centre right: Millennium seed bank.Bottom left: TL: Erica recurvata (Critically Endangered), TR: E. verticillata (Extinct in the Wild) (images MDP); BL: E. turgida (Extinct in the Wild; image AL); BR: E. baueri (Endangered; image RB-M). Bottom right: Seth Musker performs field work in the Western Cape sampling for a phylogenomics project on Erica species complexes (image MDP).

Hva forklarer Øresundsregiones fremvekst? Undersøkelsen er en casestudie av Øresundsregionen. Undersøkelsens hovedproblemstilling er Hva forklarer Øresundsregionens fremvekst? Denne problemstillingen ledsages nødvendig vis av spørsmålet: Hva er Øresundsregionen? For å besvare hovedproblemstillingen benyttes en analysemodell bestående av tre analytiske komponenter: 1) fire regionbyggende drivkrefter, 2) en initieringsinstans og 3) oppnådd integrasjon. De fire regionbyggende drivkreftene som er strukturelle forklaringsvariabler i undersøkelsen er henholdsvis statlig regionalisering, identitetsregionalisme, utviklingsregionalisme og påtrykket fra Brussel. Oppnådd integrasjon som er undersøkelsens avhengige variabel deles inn i oppnådd økonomisk, kulturell og politisk integrasjon. Initieringsinstansen som innebærer en politikkutformende regionbyggende aktør fungerer som et bindeledd mellom de strukturelle forklaringsvariablene og den oppnådde integrasjonen. I denne undersøkelsen betraktes Øresundskomiteen som initieringsinstans. Når det gjelder Øresundskomiteens regionbyggende politikk for å fremme integrasjon i regionen, viste gjennomgangen av sentrale politikkdokumenter, at komiteens målsetninger og strategier fremfor alt er knyttet til økonomisk vekst og økonomisk integrasjon. Komiteen har få målsetninger og strategier om å skape kulturell integrasjon, og ingen med tanke på politisk integrasjon. Undersøkelses avhengige variabel utrykkes gjennom den oppnådde økonomiske, kulturelle og politiske integrasjonen i Øresundsregionen frem til 2004. De empiriske resultatene tyder på en begrenset, men likevel observerbar økonomisk integrasjon mellom danske og svenske områder. Spesielt innefor noen utvalgte områder har man fått til merkbare resultater med henhold til grenseoverskridende aktivitet. Empirien tyder videre på liten grad av oppnådd kulturell og politisk integrasjon. Når det gjelder hvilke av de fire regionbyggende drivkreftene, viser den empiriske analysen at utviklingsregionalisme og påtrykket fra Brussel er treffende forklaringer på Øresundsregionens fremvekst. Statlig regionalisering og identitetsregionalisme er begge lite treffende forklaringer på regionens fremvekst. Det er således grunn til å betrakte Øresundsregionen som blanding av en økonomisk utviklingsregion og en euroregion.

Thesis (M. Environmental Science (Ecological Remediation and Sustainable Utilisation))--North-West University, Potchefstroom Campus, 2007. Hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) have been the main substitutes for CFCs since the signing of the Montreal Protocol in 1987. According to the literature HFCs can degrade in the troposphere by the action of OH, NO and O2 radicals, amongst others to trifluoroacetic acid (TFA). Studies have also shown that thermolysis of fluoropolymers, such as Teflon, can lead to the formation of HFCs. Water bodies with little or no outflow and high evaporation rate may have the potential to accumulate TFA, and can potentially achieve levels as high as 100 μg.l-1 in as little as 30 years. The occurrence of TFA has been detected in water and air samples from many geographical areas and studies have confirmed the fact that TFA is a ubiquitous contaminant of the hydrosphere with levels as high as 41 μg.l-1. Although information is available for the analogous compound trichloroacetic acid (TCA), little is known about the phytotoxic effects of TFA. The prediction of higher estimated future concentrations of TFA, highlights the necessity for research on the phytotoxic relevance of TFA. Both P. vulgaris and Z. mays, representative crop plants of the C3 and C4 photosynthetic pathways, have been used as test plants in this study. Initial experiments were carried out over a 3 day NaTFA treatment period with plants grown and treated in sand culture. In order to obtain better control over treatment levels, later experiments were carried out over a 14 day treatment period with plants grown and treated in water culture. In both experiments in vivo photosynthetic gas exchange and fast phase chlorophyll a fluorescence measurement were routinely measured during the treatment period. In the case of the water culture treatments additional measurements with respect to chlorophyll content and plant development were carried out. At the end of the water culture experiment freeze clamp samples were taken for in vitro Rubisco analysis, and dry weight of roots and shoots were measured. In a separate experiment the effect of trifluoroacetate (NaTFA) and trichloroacetate (NaTCA) on photosynthetic electron transport was studied by measuring oxygen evolution of isolated thylakoids. Motivated by observations of NaTFA treatment on plant growth, a further simple experiment was done to determine the effect of NaTFA and NaTCA on cell growth by means of a bioassay. The results of this study have shown that trifluoroacetate affects not only photosynthesis, but also the utilisation of photosynthates. Photosynthetic gas exchange measurements indicated that stomatal conductance were initially (day 4 and 8 of treatment) increased by low NaTFA concentrations (0.625 mg.l-1) and then subsequently reduced by higher concentrations (40- 160 mg.l-1) for both P. vulgaris and Z. mays. Photosynthetic gas exchange data indicated increasing reduction of Rubisco andlor PEP-case activity with increasing NaTFA concentration. The reduction in Rubisco activity was also confirmed by Rubisco activity assays, which displayed decreases with increasing NaTFA treatment levels (0.625-160 mg.l-1), for both P. vulgaris and Z. mays. The photosynthetic gas exchange data also showed a decline in Jmax which suggested that RuBP regeneration became limiting with increasing NaTFA concentrations, especially in the case of Z. mays. This finding was corroborated by the chlorophyll a fluorescence data, indicating that the formation of reducing equivalents (μR0) as reduced by NaTFA treatment. In vitro measurements of oxygen evolution on isolated thylakoid membranes revealed that trifluoroacetate partly inhibited the photosynthetic electron transport between QA and QB, as well as on the electron acceptor side of PSII (OEC), similarly to inhibition induced by trichloroacetate. These last two mentioned sites of inhibition were however shown not to be the primary point of inhibition of photosynthesis by chlorophyll a fluorescence measurements, and that FNR was also inhibited. Photosynthesis in Z. mays was more severely affected, possibly due to the complex nature of the C, photosynthetic pathway. The accumulation of starch in chloroplasts of treated plants (observed by TEM, in Z. mays) and the observation that all NaTFA concentrations severely reduced root growth, suggested that the inhibition of root growth (more severe for Z. mays) and photosynthate utilisation was an additional cause of the phytotoxic effects of trifluoroacetate. Furthermore the fact that it has been shown that trifluoroacetate affects plant growth and development, in both species, may be due to induced changes in auxin activity. The combination of subtle effects of root growth inhibition and simultaneous stimulation of stomatal conductance suggest that trifluoroacetate may have marked effects on crops and natural vegetation, even at low environmental relevant concentrations, if an additional stress such as drought is added. The fact that this study has shown some phytotoxic effect of trifluoroacetate at much lower concentration than previously reported (0.625 mg NaTFA.l-1) and the fact that environmental concentrations are predicted to rise by orders of magnitude, point out the relevance of this work in the understanding of this pollutant's phytotoxicity. Masters

Hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) have been the main substitutes for CFCs since the signing of the Montreal Protocol in 1987. According to the literature HFCs can degrade in the troposphere by the action of OH, NO and O2 radicals, amongst others to trifluoroacetic acid (TFA). Studies have also shown that thermolysis of fluoropolymers, such as Teflon, can lead to the formation of HFCs. Water bodies with little or no outflow and high evaporation rate may have the potential to accumulate TFA, and can potentially achieve levels as high as 100 g.l-1 in as little as 30 years. The occurrence of TFA has been detected in water and air samples from many geographical areas and studies have confirmed the fact that TFA is a ubiquitous contaminant of the hydrosphere with levels as high as 41 g.l-1. Although information is available for the analogous compound trichloroacetic acid (TCA), little is known about the phytotoxic effects of TFA. The prediction of higher estimated future concentrations of TFA, highlights the necessity for research on the phytotoxic relevance of TFA. Both P. vulgaris and Z. mays, representative crop plants of the C3 and C4 photosynthetic pathways, have been used as test plants in this study. Initial experiments were carried out over a 3 day NaTFA treatment period with plants grown and treated in sand culture. In order to obtain better control over treatment levels, later experiments were carried out over a 14 day treatment period with plants grown and treated in water culture. In both experiments in vivo photosynthetic gas exchange and fast phase chlorophyll a fluorescence measurement were routinely measured during the treatment period. In the case of the water culture treatments additional measurements with respect to chlorophyll content and plant development were carried out. At the end of the water culture experiment freeze clamp samples were taken for in vitro Rubisco analysis, and dry weight of roots and shoots were measured. In a separate experiment the effect of trifluoroacetate (NaTFA) and trichloroacetate (NaTCA) on photosynthetic electron transport was studied by measuring oxygen evolution of isolated thylakoids. Motivated by observations of NaTFA treatment on plant growth, a further simple experiment was done to determine the effect of NaTFA and NaTCA on cell growth by means of a bioassay. The results of this study have shown that trifluoroacetate affects not only photosynthesis, but also the utilisation of photosynthates. Photosynthetic gas exchange measurements indicated that stomatal conductance were initially (day 4 and 8 of treatment) increased by low NaTFA concentrations (0.625 mg.l-1) and then subsequently reduced by higher concentrations (40- 160 mg.l-1) for both P. vulgaris and Z. mays. Photosynthetic gas exchange data indicated increasing reduction of Rubisco andlor PEP-case activity with increasing NaTFA concentration. The reduction in Rubisco activity was also confirmed by Rubisco activity assays, which displayed decreases with increasing NaTFA treatment levels (0.625-160 mg.l-1), for both P. vulgaris and Z. mays. The photosynthetic gas exchange data also showed a decline in Jmax which suggested that RuBP regeneration became limiting with increasing NaTFA concentrations, especially in the case of Z. mays. This finding was corroborated by the chlorophyll a fluorescence data, indicating that the formation of reducing equivalents (R0) as reduced by NaTFA treatment. In vitro measurements of oxygen evolution on isolated thylakoid membranes revealed that trifluoroacetate partly inhibited the photosynthetic electron transport between QA and QB, as well as on the electron acceptor side of PSII (OEC), similarly to inhibition induced by trichloroacetate. These last two mentioned sites of inhibition were however shown not to be the primary point of inhibition of photosynthesis by chlorophyll a fluorescence measurements, and that FNR was also inhibited. Photosynthesis in Z. mays was more severely affected, possibly due to the complex nature of the C, photosynthetic pathway. The accumulation of starch in chloroplasts of treated plants (observed by TEM, in Z. mays) and the observation that all NaTFA concentrations severely reduced root growth, suggested that the inhibition of root growth (more severe for Z. mays) and photosynthate utilisation was an additional cause of the phytotoxic effects of trifluoroacetate. Furthermore the fact that it has been shown that trifluoroacetate affects plant growth and development, in both species, may be due to induced changes in auxin activity. The combination of subtle effects of root growth inhibition and simultaneous stimulation of stomatal conductance suggest that trifluoroacetate may have marked effects on crops and natural vegetation, even at low environmental relevant concentrations, if an additional stress such as drought is added. The fact that this study has shown some phytotoxic effect of trifluoroacetate at much lower concentration than previously reported (0.625 mg NaTFA.l-1) and the fact that environmental concentrations are predicted to rise by orders of magnitude, point out the relevance of this work in the understanding of this pollutant's phytotoxicity. Thesis (M. Environmental Science (Ecological Remediation and Sustainable Utilisation))--North-West University, Potchefstroom Campus, 2007.