Welcome to the 31st IUBS General Assembly and Conference on ...

Environmental (conservation) education is recognized as
one of <strong>the</strong> processes that shall contribute individuals <strong>to</strong>
change, by acquiring essential knowledge <strong>and</strong> skills <strong>to</strong>
take positive action <strong>to</strong>wards a better environment,
especially regarding natural ecosystems. As new
environmental problems arise, conservation education
has <strong>to</strong> include <strong>the</strong>se new <strong>and</strong> future scenarios, <strong>the</strong>
science, <strong>the</strong> methods, <strong>the</strong> resources <strong>and</strong> <strong>the</strong> technology,
<strong>to</strong> cope with <strong>the</strong> challenge. Thirty years after <strong>the</strong> first
time <strong>IUBS</strong> discussed <strong>and</strong> integrated Environmental
education in<strong>to</strong> its scope of work, we will review <strong>the</strong> state
of <strong>the</strong> art <strong>and</strong> <strong>the</strong> challenges ahead.
species can be described within this century, <strong>and</strong> before
<strong>the</strong>y go extinct.
H 2 S acts an antioxidative role in delaying
maturation <strong>and</strong> senescence in plants
Shuaiping GAO, Shiping LI, Lanying HU,
Yanhong LI <strong>and</strong> Hua ZHANG
School of Biotechnology <strong>and</strong> Food Engineering, Hefei
University of Technology, Hefei 230009, China. Email:
zh<strong>and</strong>zhy@yahoo.com.cn
Global databases reveal progress in
discovering all species on Earth: will most
species be discovered before <strong>the</strong>y go
extinct?
Mark J COSTELLO
Leigh Marine Labora<strong>to</strong>ry, University of Auckl<strong>and</strong>, New Zeal<strong>and</strong>.
Email: m.costello@auckl<strong>and</strong>.ac.nz
Claims that taxonomists are in decline <strong>and</strong> tens of millions
of species remain <strong>to</strong> be discovered, have led <strong>to</strong> suggestions
that taxonomy is fruitless because most species will be
extinct before <strong>the</strong>y are described. The advent of
biodiversity informatics is enabling production of global
databases <strong>and</strong> associated statistics, <strong>and</strong> may be improving
efficiency <strong>and</strong> productivity in <strong>the</strong> process of discovering
life on Earth. Some recent results have been surprising,
such as <strong>the</strong> continued high rates of discovery of new
species in well‐studied geographic regions. More
statistically robust predictions of how many species may
exist on Earth have been in <strong>the</strong> range of 2–12 million, with
hyper‐estimates of tens of millions of species finding no
support. Estimates of extinction rates are now more
variable than estimates of species richness on Earth.
Evidence that <strong>the</strong>re are more taxonomists describing
species than ever before, <strong>and</strong> <strong>the</strong>ir numbers have been
increasing, have been more controversial. If <strong>the</strong>re really is
increased taxonomic effort, <strong>the</strong>n does this explain <strong>the</strong>
continued high rates of species discovery ra<strong>the</strong>r than <strong>the</strong>
ease with which new species may be found? This
presentation examines this evidence <strong>and</strong> its implications. It
concludes that with modest increase in effort that most
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Accumulating evidence shows that hydrogen sulfide
(H 2 S) plays various physiological roles in plants, such as
seed germination, root organogenesis, abiotic stress
<strong>to</strong>lerance, <strong>and</strong> senescence of cut flowers. However,
whe<strong>the</strong>r H 2 S participates in <strong>the</strong> regulation of
maturation <strong>and</strong> senescence in plants remains unclear. In
<strong>the</strong> present work, cut flowers <strong>and</strong> postharvest fruits
were used as <strong>the</strong> experimental materials, <strong>the</strong> effects of
H 2 S on postharvest shelf life in fruits or vase life in cut
flowers were reviewed, <strong>and</strong> <strong>the</strong> mechanism of
antioxidant metabolism involving in H 2 S signal
regulation in plants was discussed. It showed that H 2 S
was involved in preventing senescence of cut flowers
<strong>and</strong> prolonging flower vase life in a wide spectrum of
botanical species including herbaceous <strong>and</strong> woody
plants. It also anticipated in delaying <strong>the</strong> ripening <strong>and</strong>
senescence in postharvest fruits, such as <strong>the</strong> strawberry
<strong>and</strong> pear. Fur<strong>the</strong>r investigation showed that H 2 S
maintained higher activities of antioxidant enzymes
such as catalase (CAT), guaiacol peroxidase (POD),
ascorbate peroxidase (APX), glutathione reductase (GR),
SOD <strong>and</strong> lower activities of lipoxygenase (LOX) relative
<strong>to</strong> untreated controls. H 2 S also reduced malondialdehyde
(MDA),hydrogen peroxide (H 2 O 2 ) <strong>and</strong> superoxide anion
( • O 2− ) <strong>to</strong> levels below control plants. We interpret <strong>the</strong>se
data as indicating that H 2 S plays an antioxidant function
in prolonging vase life of cut flowers <strong>and</strong> delaying
postharvest shelf life of fruits. Its antioxidant role in
alleviating peroxidative damage induced by ROS
overproduction in plants might be a universal event.
Harvesting microalgae using bioflocculating
agents produced by Solibacillus silvestris
for efficient bioenergy production