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In this study,LI-6400XT portable photosynthesis test system was employed to observe physiological indicators of 8 widely used species of Sha river′s plant corridor in Chengdu.Furthermore,the carbon sequestration,oxygen release capacity,cooling and humidification effects were also evaluated.Our results indicated: The capacity of carbon sequestration,oxygen release,cooling and humidification effect per unit of leaf area was in the order of summer autumn spring.The order of daily carbon sequestration and oxygen release capability per unit of leaf area from strong to weak was O.fragrans,S.babylonica,C.camphora,F.virens,E.sylvestris,G.biloba,C.pedunculatum and M.glyptostroboides;and the order of annual carbon sequestration and oxygen release capability per unit of leaf area from strong to weak was S.babylonica,C.camphora,F.virens,G.biloba,O.fragrans,C.pedunculatum,M.glyptostroboides and E.sylvestris.The capabilities of daily cooling and humidification effect per unit leaf area of the trees pecies from strong to weak was S.babylonica,E.sylvestris,M.glyptostroboides,C.pedunculatum,F.virens,C.camphora,G.biloba and O.fragrans.It was estimated that the total amount of annual carbon sequestration of trees in Sha river was about 5.87×104 t and the oxygen release was about 4.27×104 t.Based on the above analysis of the main tree species,it was suggested that S.babylonica,O.fragrans,E.sylvestris,and C.camphora should be taken as the priority tree species.Due to the weak C sequestration oxygen release and cooling and humidification effect,G.biloba should not be virescenced in a large area,but could be used as a longevous and ornamental tree species.

A smut fungus Ustilago esculenta causes enlargement of infected culms of Zizania latifolia,a perennial aquatic grass.The swollen culm is used as a vegetable in China and some southeastern countries.Interaction between the fungus and the host plant plays a vital role in the enlargement of infected culms.U.esculenta is a biotrophic endophyte that completes its life cycle in host tissues.In our previous studies,we have observed that Z.latifolia plants infected by U.esculenta showed higher net photosynthetic rate and chlorophyll content,which is different from the results obtained after induction by pathogens.However,in this plant-fungus association,detailed biochemical,physiological or morphological changes,and the role of reactive oxygen species(ROS) and their scavenging system as well as photosystem(PS) Ⅱ efficiency during this interactive process,have not been studied.To ascertain the actual relationship between U.esculenta and Z.latifolia,we determined the antioxidative system and chlorophyll fluorescence in leaves of Z.latifolia. The experiment was carried out at Zhejiang University,Hangzhou.Z.latifolia plants(cv."Zhejiao No.2",a double-harvest variety) were used in this study.There were 16 pots(10 plants each pot) in each treatment.These plants were regularly watered to keep a 10 cm-layer of water above soil.Pesticides were sprayed for the prevention of pests and diseases if needed. In this study,the response of Z.latifolia plants to U.esculenta infection was investigated,and activities of antioxidant enzymes,superoxide radical(O·-2) formation rate,hydrogen peroxide(H2O2) content,malondialdehyde(MDA) content,and chlorophyll fluorescence were determined.Our results showed that plant height,leaf length,leaf width,leaf thickness,root length,biomass of culm,root and aboveground were reduced,but tiller number was increased by U.esculenta infection.Meanwhile,U.esculenta infection caused increase in activities of ascorbate peroxidase(APX),catalase(CAT),peroxidase(POD),glutathione reductase(GR),superoxide dismutase(SOD) and H2O2 content,but decrease in O·-2 formation rate and MDA content(P0.05).The decrease of O·-2 formation rate in U.esculenta infected plants might be due to the higher SOD activity,which transformed O·-2 to H2O2 and O2.In this study,we also observed that quantum efficiency of PS Ⅱ(ΦPSⅡ) and electron transport rate(ETR) were slightly increased(P 0.05),but non-photochemical quenching(NPQ) was decreased by U.esculenta infection(P 0.05).It is observed that maximum quantum efficiency of PSⅡ(Fv/Fm) was not altered by U.esculenta infection,indicating that U.esculenta infection may not be a biotic stress for Z.latifolia plants.Therefore,based on the changes of the plant growth indices,PS Ⅱ efficiency and membrane lipid peroxidation in infected plants,we found the interactive relationship between U.esculenta and Z.latifolia was neither pathogenic nor mutualistic.

This paper describes the development of a novel infrared point-diffraction interferometer (IPDI), which can be readily applied to real-time quantitative phase measurement. We generate reference wave with the help of Michelson-like unit combined with a low-pass spatial filter, and extract the phase information using windowed Fourier transform algorithm from single off-axis fringes. The arrangement of the proposed setup offers a quasi-common-path geometry, which could significantly minimize the systematic errors. The proposed method of IPDI is effective and sufficient for the dynamic process measurement of small deformation with higher spatial resolution compared with the conventional off-axis scheme. The feasibility of the proposed setup is demonstrated, followed by methods of reconstruction and system calibration. The nanoscale repeatability is achieved in our experiment.

Three-dimensional spatio-temporal variation characteristics of pulse intensity is numerically simulated in detail in multi-pass amplifier of high power laser system.Theoretical calculation indicates that the complicated spatio-temporal distortion occurs as the pulse with specific spatio-temporal distribution passes the amplifier.This change imposes some difficulties on shaping prediction of the pulse power.The curve fitting method of input-output integral energy is proposed to achieve the inverse prediction of inject pulse shape formulti-pass amplifier system with high precision.The better prediction result is achieved not only for square pulse shape but also for multiple-steps complex pulse output,the relative power deviation reaches up to 0.032%for the square pulse output,and 0.78% for multiple-steps complex pulse output.In addition,the inverse prediction of more complicated Haan pulse is achieved.The relative power deviation is 0.13%.This method has not only high precision but also rapid computation and strong applicability.