Sample Paper_Submission.pdf

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Therefore, algal-bloom control is an important issue for water environment protection.
Till now, there are three kinds of methods used for algal control, i.e. physical methods, chemical
treatment and biological manipulation. Physical methods has mechanical cleanup, carbon absorption,
ultrasonic disturbance, and ultraviolet irradiation, etc, which usually need expensive instruments, are
time-consuming and just available on small-scale waterbodies[3-7]. The algicides used for chemical
treatment usually include heavy metal compounds, pro-oxidants and organic amines, which are
cost-effective but with broad-spectrum toxicity to all the aquatic organisms[8-9]. Biological manipulation
utilizes fish, shell, zooplankton, epiphyte, actinomycete, bacteria, phycophage and etc to directly or
indirectly control the algal biomass. Microbes preferably with high mutation rates are considered not be
singly used in algal control, and moreover, algal heavy extracellular polymeric substances or other
complicated factors caused algae-grazing zooplankton and algae-lysing microbes just under
investigation[10-12]. The successful application cases are primarily on filter-feeding fish but with unstable
control effects and potential ecological risks.
In the last decades, there has been an increasing focus on the prospect of exploiting macrophytes as an
alternative strategy for controlling algal bloom. Barley straw is the most successful macrophyte in the
practical application of algal-bloom control[13]. Some reports revealed that to release inhibitory second
metabolites might be the inhibitory mode of action of barley straw, and associated epiphytes (e.g.
Pycnidiophora dispersa Clum、Zopfiella、Fusarium tricinctum) and even invertebrates might be also
involved in the process[14-19]. At present, other extensively distributed and abundant terrestrial plants are
investigated. Ridge et al. reported leaf litter had inhibition on algae, but less effective than barley straw[20].
Wang et al. observed decomposed rice straw had similar inhibitory effects with barley straw on several
kinds of cyanobacteria, e.g. Microcystis aeruginosa[21]. Terrestrial plant has some potential problems to
be applied for algal control, such as large one-off dosage, its long time before inhibitory effects occurs,
unstable effects, bad to landscape and tourism, hard to dispose its residue, its ambiguous ecological
impacts to aquatic organisms.
Considering that the low efficiency, limited applied scale, secondary pollution from the methods
mentioned above, it is still urgent to find other environment-friendly, cost-effective and convenient
methods. In aquatic ecological system, complicated interactions exist among various organisms, such as
prey relationships, the competition for nutrient, living space and light and allelopathy[22, 23]. All
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