Publications by authors named "Dayong Fan"

20 Publications

  • Page 1 of 1

Contrasting vegetation response to climate change between two monsoon regions in Southwest China: The roles of climate condition and vegetation height.

Sci Total Environ 2021 Aug 13;802:149643. Epub 2021 Aug 13.

School of Ecology and Nature Conservation, Beijing Forest University, Beijing, China.

Southwest China is an important biodiversity hotspot in the world and is controlled by the Pacific and Indian Ocean monsoon in the east and west part respectively. However, how abiotic and biotic factors affect the response of vegetation to climate change in different monsoon regions is still not clear. Here we used the annual change rate of growing-season normalized difference vegetation index (NDVI trend) during 1982-2015 to explore the vulnerability of vegetation (forests and shrubs) activity to climate change in southwest China. We examined NDVI trend in relation to: 1) climate change trends, i.e. annual change rate of water and energy availability, indicated by the Palmer Drought Index (PDSI) and potential evapotranspiration (PET), respectively; 2) climatic condition, i.e. mean PDSI and PET during 1982-2015; 3) vegetation height; 4) biome type; 5) monsoon region. The results showed that NDVI generally increased in the Pacific monsoon region, especially in the southern areas, probably because the vegetation under more productive climate were more resistant to climate change, and also because decreased temperature lead to lower evapotranspiration which alleviated the slight drought trend in this region. In contrast, NDVI generally decreased in the Indian Ocean monsoon region which showed more pronounced drought trend, especially in the tall subalpine and tropical forests of Southeast Tibetan Mountains, which supports the "hydraulic limitation hypothesis" that vegetation height interacted with climate change in affecting vegetation vulnerability. Our analysis highlighted the critical roles of different monsoon systems, climate condition and vegetation height in affecting ecosystem vulnerability. We suggest that the (sub)tropical forests in the Pacific monsoon region may have act as an important carbon sink during the past decades, while the tall forests in Southeast Tibetan mountains (a biodiversity center with high carbon stock) are highly vulnerable to climate change and should have priority in ecosystem protection.
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http://dx.doi.org/10.1016/j.scitotenv.2021.149643DOI Listing
August 2021

Wah Soon Chow, a teacher, a friend and a colleague.

Photosynth Res 2021 Aug;149(1-2):253-258

Climate Change Cluster (C3), University of Technology Sydney, Sydney, NSW, 2007, Australia.

To finish this special issue, some friends, colleagues and students of Prof. Chow (Emeritus Professor, the Research School of Biology, the Australian National University) have written small tributes to acknowledge not only his eminent career but to describe his wonderful personality.
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http://dx.doi.org/10.1007/s11120-021-00864-wDOI Listing
August 2021

The construction of a single-crystalline SbSI nanorod array-WO heterostructure photoanode for high PEC performance.

Chem Commun (Camb) 2021 Jan;57(3):335-338

College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 116023, China.

A novel kind of highly efficient photoanode was constructed with a SbSI/WO3 heterostructurefabricated through two hydrothermal reactions followed by an iodination reaction (WO3 → Sb2S3/WO3 → SbSI/WO3). After optimizing the solvent [carbon disulfide (CS2)] for SbI3, the SbSI(CS2)/WO3 photoanode shows high-density single-crystalline SbSI nanorods growing along the polar [001] direction on WO3 nanoplates, resulting in excellent photocurrent performance (∼2.1 mA [email protected] V vs. RHE) and an improved photostability. It is evidenced that the higher crystallinity of SbSI has a positive effect on the photostability of the constructed SbSI/WO3 photoanodes.
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http://dx.doi.org/10.1039/d0cc06148dDOI Listing
January 2021

Carbohydrate saving or biomass maintenance: which is the main determinant of the plant's long-term submergence tolerance?

Photosynth Res 2021 Aug 1;149(1-2):155-170. Epub 2020 Nov 1.

College of Forestry, Beijing Forestry University, Beijing, 100083, China.

It is hypothesized that plant submergence tolerance could be assessed from the decline of plant biomass due to submergence, as biomass integrates all eco-physiological processes leading to fitness. An alternative hypothesis stated that the consumption rate of carbohydrate is essential in differing tolerance to submergence. In the present study, the responses of biomass, biomass allocation, and carbohydrate content to simulated long-term winter submergence were assessed in four tolerant and four sensitive perennials. The four tolerant perennials occur in a newly established riparian ecosystem created by The Three Gorges Dam, China. They had 100% survival after 120 days' simulated submergence, and had full photosynthesis recovery after 30 days' re-aeration, and the photosynthetic rate was positively related to the growth during the recovery period. Tolerant perennials were characterized by higher carbohydrate levels, compared with the four sensitive perennials (0% survival) at the end of submergence. Additionally, by using a method which simulates posterior estimates, and bootstraps the confidence interval for the difference between strata means, it was found that the biomass response to post-hypoxia, rather than that to submergence, could be a reliable indicator to assess submergence tolerance. Interestingly, the differences of changes in carbohydrate content between tolerant and sensitive perennials during submergence were significant, which were distinct from the biomass response, supporting the hypothesis that tolerant perennials could sacrifice non-vital components of biomass to prioritize the saving of carbohydrates for later recovery. Our study provides some insight into the underlying mechanism(s) of perennials' tolerance to submergence in ecosystems such as temperate wetland and reservoir riparian.
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http://dx.doi.org/10.1007/s11120-020-00791-2DOI Listing
August 2021

Does , an ancient and threatened species endemic to China, show eco-physiological outliers to its relatives?

Conserv Physiol 2020 14;8(1):coaa094. Epub 2020 Oct 14.

State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, No. 20, Xiangshan Nanxin Cun, Haidian District, Beijing 100093, China.

is an ancient and threatened Pinaceae species endemic to China, but its eco-physiological traits are rarely reported. We hypothesized that showed eco-physiological outliers to its Pinaceae relatives, which lead to its current endangered status. Here we collected the photosynthetic capacity ( , maximum photosynthesis rate) and branchlet hydraulic safety ( , the water potential at which a 50% loss in conductivity occurs) of Pinaceae species globally, including our measurements on . We applied the phylogenetic comparative methods to investigate: (i) the phylogenetic signal of the two key traits across Pinaceae species, and (ii) the trait-climate relationships and the photosynthesis-cavitation resistance relationship across Pinaceae species. We applied the polygenetic quantile regression (PQR) method to assess whether showed eco-physiological outliers to its Pinaceae relatives in terms of cavitation resistance and photosynthetic capacity. It was found that , and to a less extent, , had a strong phylogenetic signal consistent with niche conservation among Pinaceae species. Hydraulic safety largely determined non-threatened Pinaceae species' distribution across moisture gradients at the global scale. There was also an adaptive trade-off relationship between and . is a high cavitation resistant, low photosynthetic capacity species. It showed eco-physiological outliers to its Pinaceae relatives because it had lower and below the 10% quantile boundaries along moisture and/or temperature gradients; also, it was above the 90% quantile boundary of the and relationship across non-endangered Pinaceae species. The PQR output demonstrated that in the subtropical area of China characterized by abundant rainfall, has extra high hydraulic safety, suggesting inefficiency of carbon economy associated with either competition or other life history strategies, which lead to its current endangered status.
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http://dx.doi.org/10.1093/conphys/coaa094DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7566968PMC
October 2020

Determination of the Mono and Dibromo Derivatives Ratio Resulting from Semiconductor Bromination Using Ultraviolet-visible Absorption Spectroscopy and Gaussian Peak Fitting.

Anal Sci 2021 Apr 2;37(4):569-573. Epub 2020 Oct 2.

Guangxi Key Laboratory of Electrochemical and Magneto-chemical Functional Materials, College of Chemistry and Bioengineering, Guilin University of Technology.

The chemical-industrial production of organic semiconductors urgently needs a cheap and fast approach to determine the components' proportion of the reaction system. In the present work, the Gaussian peak fitting method was applied to process monobromo and dibromo-substituted perylene diimide mixed solutions' ultraviolet-visible absorption curves. The functional relationship formula between the peak-intensity ratio and the component ratio is then concluded. Finally, field experiments of the perylene imide brominating reaction can be used to confirm that such a formula is able to accurately calculate the proportion of ingredients in the synthesis reaction solution system.
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http://dx.doi.org/10.2116/analsci.20P273DOI Listing
April 2021

A Fast and Automatic Method for Leaf Vein Network Extraction and Vein Density Measurement Based on Object-Oriented Classification.

Front Plant Sci 2020 5;11:499. Epub 2020 May 5.

Inspection Department of Guangxi Medical College, Nanning, China.

Rapidly determining leaf vein network patterns and vein densities is biologically important and technically challenging. Current methods, however, are limited to vein contour extraction. Further image processing is difficult, and some leaf vein traits of interest therefore cannot be quantified. In this study, we proposed a novel method for the fast and accurate determination of leaf vein network patterns and vein density. Nine tree species with different leaf characteristics and vein types were applied to verify this method. To overcome the image processing difficulties at the microscopic scale, we adopted the remote object-oriented classification method applied comprehensively in the field of remote sensing research. The key to this approach is to determine the universally applicable leaf vein extraction threshold values (scale parameter, shape parameter, compactness parameter, brightness feature, spectral feature and geometric feature). Based on our analysis, the following recommended threshold values were determined: the scale parameter was 250, the shape parameter was 0.7, the compactness parameter was 0.3, the brightness feature value was 230∼280, the spectral feature value was 180∼230, and the geometric feature value was less than 2. With the optimal extraction parameters applied, the extraction precision was above 96.40% on average for the nine species studied. The leaf vein density calculation rate increased by more than 87.3% compared to that of the traditional methods. The results showed that this method is accurate, fast, flexible and complementary to existing technologies. It is an effective tool for the fast extraction of vein networks and the exploration of leaf vein characteristics, particularly for large-scale studies in plant vein physiology.
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http://dx.doi.org/10.3389/fpls.2020.00499DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7214732PMC
May 2020

SnS Nanosheets/H-TiO Nanotube Arrays as a Type II Heterojunctioned Photoanode for Photoelectrochemical Water Splitting.

ChemSusChem 2019 Mar 4;12(5):961-967. Epub 2019 Feb 4.

Department of Chemistry, University of Missouri-Kansas City, Kansas City, Missouri, 64110, USA.

Improving the separation efficiency of photogenerated electron-hole pairs and the conductivity of electrons to photoanode substrates are critical to achieve high-performance photoelectrochemical (PEC) water splitting. Here, a SnS /H-TiO /Ti heterojunction photoanode was fabricated with SnS nanosheets vertically grown on hydrogen-treated TiO (H-TiO ) nanotube arrays on a Ti substrate. It showed a significantly enhanced photocurrent of 4.0 mA cm at 1.4 V (vs. reversible hydrogen electrode) under AM 1.5 G illumination, 70 times higher than that of SnS /TiO /Ti. Kelvin probe force microscopy measurements indicated that photogenerated electrons could be easily transported through the SnS /H-TiO interface but not through the SnS /TiO interface. Through hydrogen treatment, defects were created in H-TiO nanotubes to convert type I junctions to type II with SnS nanosheets. As a result, a high efficiency of electron-hole separation at the SnS /H-TiO interface and a high electron conductivity in H-TiO nanotubes were achieved and improved PEC performance. These findings show an effective route towards high-performance photoelectrodes for water splitting.
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http://dx.doi.org/10.1002/cssc.201802691DOI Listing
March 2019

Functional coordination between leaf traits and biomass allocation and growth of four herbaceous species in a newly established reservoir riparian ecosystem in China.

Ecol Evol 2018 Dec 8;8(23):11372-11384. Epub 2018 Nov 8.

The Key Laboratory of Oasis Eco-agriculture Xinjiang Production and Construction Corps Shihezi University Shihezi China.

The flood-dry-flood cycle in the reservoir riparian zone (RRZ) of the Three Gorges Dam has dramatically altered the riparian ecosystem structure and composition. Previous field studies have shown that leaf traits varied greatly and were restricted to the lower-investment and faster-return end of the global leaf spectrum, which are typical characteristics of fast-growing species. However, it is unclear as to the mechanism underpinning the growth potential of these species and how it will respond to soil nutrient availability and temperature. Here, we linked the plant functional traits of four representative dominant C herbaceous species (, , and ) to their relative growth rates (RGR) under ambient and elevated temperatures, with different nitrogen and phosphorus levels, to explore the potential mechanism of species growth in the newly established reservoir riparian ecosystem in the Three Gorges Reservoir Area, China. We grew seedlings of these species in four open-top chambers, with three levels of nutrient supplies under two temperature gradients (ambient temperature and an elevated temperature of 4°C). We found that the responses of the RGR and plant traits to soil N and P supply levels and temperature varied considerably among studied species. displayed the lowest RGR associated with relatively low specific leaf area (SLA), leaf nitrogen content (LN), stem mass ratio (SMR), and high leaf mass ratio (LMR) and was less affected by soil N and P supply levels and temperature. and showed the highest RGR compared to the other two species grown at the substrate of N = 0.4 mg/g, P = 0.2 mg/g at ambient air temperature, associated with a relatively high SMR, low LMR and low plant carbon content (PCC). However, the RGR advantage of the two species was diminished at elevated temperatures, while showed the highest RGR compared to the other species. Across all datasets, the RGR had no association with the leaf area ratio (LAR) and SLA. The RGR also showed no significant relationships with the LN and leaf phosphorus content (LP). On the other hand, the RGR was captured adequately by the SMR, which can therefore be considered as a powerful functional marker of species' functioning in this newly established reservoir riparian ecosystem. Our study provides some insight into the underlying mechanisms of species growth in reservoir riparian ecosystems.
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http://dx.doi.org/10.1002/ece3.4494DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6303726PMC
December 2018

Effectively Measuring Respiratory Flow With Portable Pressure Data Using Back Propagation Neural Network.

IEEE J Transl Eng Health Med 2018 26;6:1600112. Epub 2018 Jan 26.

Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen518055China.

Continuous respiratory monitoring is an important tool for clinical monitoring. The most widely used flow measure device is nasal cannulae connected to a pressure transducer. However, most of these devices are not easy to carry and continue working in uncontrolled environments which is also a problem. For portable breathing equipment, due to the volume limit, the pressure signals acquired by using the airway tube may be too weak and contain some noise, leading to huge errors in respiratory flow measures. In this paper, a cost-effective portable pressure sensor-based respiratory measure device is designed. This device has a new airway tube design, which enables the pressure drop efficiently after the air flowing through the airway tube. Also, a new back propagation (BP) neural network-based algorithm is proposed to stabilize the device calibration and remove pressure signal noise. For improving the reliability and accuracy of proposed respiratory device, a through experimental evaluation and a case study of the proposed BP neural network algorithm have been carried out. The results show that giving proper parameters setting, the proposed BP neural network algorithm is capable of efficiently improving the reliability of newly designed respiratory device.
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http://dx.doi.org/10.1109/JTEHM.2017.2688458DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5951610PMC
January 2018

In-situ ion-exchange synthesis AgS modified SnS nanosheets toward highly photocurrent response and photocatalytic activity.

J Colloid Interface Sci 2018 Feb 31;512:784-791. Epub 2017 Oct 31.

Guangxi Key Laboratory of Electrochemical and Magneto-chemical Functional Materials, Guilin University of Technology, Guilin, PR China; College of Chemistry and Bioengineering, Guilin University of Technology, Guilin, PR China.

Heterojunction photocatalyst systems are deemed to be an excellent option to improve the photocatalytic behavior of a material. In this paper, AgS/SnS heterojunction photocatalysts were prepared by a simple in-situ ion exchange method from SnS nanosheets. The AgS/SnS composite photoanode exhibits 13.99 μA/cm photocurrent density at 0.7 V (vs. Ag/AgCl) in 0.5 M NaSO solution and a significant increase in photocatalytic activity compared to SnS nanosheets. AgS (8 wt%)/SnS composite shows the highest activity (0.0440 mg/min) in the degradation of MO and good stability. The reactive species trapping experiments confirmed hole (h) and hydroxyl radical (OH) are active groups and play key roles in the photocatalytic degradation reaction. The highly effective photoelectrochemical and phocatalytic activities of AgS/SnS heterojunctions are attributed to the efficient separation of photogenerated hole-electron pairs. This work may provide a novel concept for the rational design of high performance SnS-based photocatalysts.
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http://dx.doi.org/10.1016/j.jcis.2017.10.112DOI Listing
February 2018

Epigenetic map and genetic map basis of complex traits in cassava population.

Sci Rep 2017 01 25;7:41232. Epub 2017 Jan 25.

The Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agriculture Sciences, Haikou, China.

Cassava (Manihot esculenta Crantz) is an important tropical starchy root crop that is adapted to drought but extremely cold sensitive. A cold-tolerant, high-quality, and robust supply of cassava is urgently needed. Here, we clarify genome-wide distribution and classification of CCGG hemi-methylation and full-methylation, and detected 77 much candidate QTLs for cold stress and 103 much candidate QTLs for storage root quality and yield in 186 cassava population, generated by crossing two non-inbred lines with female parent KU50 and male parent SC124 (KS population). We developed amplified-fragment single nucleotide polymorphism and methylation (AFSM) genetic map in this population. We also constructed the AFSM QTL map, identified 260 much candidate QTL genes for cold stress and 301 much candidate QTL genes for storage root quality and yield, based on the years greenhouse and field trials. This may accounted for a significant amount of the variation in the key traits controlling cold tolerance and the high quality and yield of cassava.
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http://dx.doi.org/10.1038/srep41232DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5264614PMC
January 2017

Insight into the charge transfer in particulate TaN photoanode with high photoelectrochemical performance.

Chem Sci 2016 Jul 16;7(7):4391-4399. Epub 2016 Mar 16.

State Key Laboratory of Catalysis , Dalian Institute of Chemical Physics , Chinese Academy of Sciences , Dalian National Laboratory for Clean Energy , The Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) , Zhongshan Road 457 , Dalian , 116023 , China . Email:

Charge separation is one of the most critical factors for generating solar fuels photoelectrochemical water splitting, but it is still not well understood. This work reveals the fundamental role of charge transfer in photoanodes for achieving high charge separation efficiency. Specifically, we fabricated a particulate TaN photoanode by a bottom-up method. By improving the charge separation with refined necking treatment, the photocurrent is increased by two orders of magnitude. The charge separation efficiency () is analyzed by dividing it into charge generation efficiency () and transportation efficiency (). Necking treatment is found to substantially improve the electron transfer. Transient photovoltage (TPV) measurements based on the Dember effect is used to confirm the benefit of necking treatment in improving the charge transportation. The superior electron transfer in the necked-TaN electrode is further evidenced by the facile electron exchange reaction with the ferri/ferrocyanide redox couple. Moreover, cobalt phosphate is found to promote both charge separation and surface reaction, resulting in a photocurrent of 6.1 mA cm at 1.23 V RHE, which is the highest response for a particulate photoanode.
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http://dx.doi.org/10.1039/c6sc00245eDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6014074PMC
July 2016

Roles of adsorption sites in electron transfer from CdS quantum dots to molecular catalyst cobaloxime studied by time-resolved spectroscopy.

Phys Chem Chem Phys 2016 Jun;18(26):17389-97

State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, China.

Electron transfer from CdS quantum dots (QDs) to cobaloxime (Co(dmgH)2pyCl) is demonstrated by transient absorption spectroscopy (TAS), and further confirmed using photoluminescence (PL) techniques. The analysis of the PL quenching results offers a novel way to understand the roles of the surface adsorption sites of CdS QDs in the performance of charge transfer in the CdS QDs-cobaloxime hybrid system. Two types of quenching dynamics reveal that there are two different adsorption modes of cobaloxime on the CdS QD surface. When cobaloxime substitutes the surface capping ligands of CdS QDs under low cobaloxime concentrations, the transfer is nearly unfavorable for both the free and trapped electrons. When cobaloxime occupies the surface defect sites of the CdS QDs under high cobaloxime concentrations, the transfer of both the free and trapped electrons is very effective, with an extremely high quenching rate constant of ∼10(12) M(-1) s(-1). Therefore, controlling the molecular adsorption sites and adjusting the surface defect properties of semiconductor QDs provide a strategy to improve the electron transfer efficiency of the QDs-cobaloxime photocatalytic system.
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http://dx.doi.org/10.1039/c6cp02808jDOI Listing
June 2016

Dual Extraction of Photogenerated Electrons and Holes from a Ferroelectric Sr0.5Ba0.5Nb2O6 Semiconductor.

ACS Appl Mater Interfaces 2016 Jun 23;8(22):13857-64. Epub 2016 May 23.

State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy , Dalian 116023, China.

The separation of photogenerated charges is a critical factor in photocatalysis. Recently, anomalous photovoltaic (APV) field effects (Voc ∼ 10(3) V/cm) in ferroelectrics, with their strong driving force for charge separation, have attracted much attention in photocatalysis and photoelectrocatalysis. However, it is still unknown whether photogenerated electrons and holes can be simultaneously extracted by the strong driving force toward the surface of ferroelectrics and can become available for surface reactions. This issue becomes critically important in photocatalysis because the surface reaction utilizes both the electrons and holes that reach the surface. In this work, a model lateral symmetric structure, metal/Sr0.5Ba0.5Nb2O6/metal (metal = Ag or Pt), as an electrode was fabricated. The dual extractions of photogenerated electrons and holes on the two opposite metal electrodes were achieved, as revealed by photovoltaic and ferroelectrical hysteresis measurements and photoassisted Kelvin probe force microscopy (KPFM). It was found that the high Schottky barriers of the two opposite Sr0.5Ba0.5Nb2O6-Pt electrodes are key factors that alter the two space charge regions (SCRs) by a poling effect. The resulting built-in electrical fields with parallel directions near both electrodes significantly enhance the charge separation ability. Our model unravels the driving force of charge separation in ferroelectric semiconductors, thus demonstrating the potential for highly efficient charge separation in photocatalysis.
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http://dx.doi.org/10.1021/acsami.6b00809DOI Listing
June 2016

Eco-physiological adaptation of dominant tree species at two contrasting karst habitats in southwestern China.

F1000Res 2013 9;2:122. Epub 2013 May 9.

State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China ; Graduate University of the Chinese Academy of Sciences, Beijing, 100093, China.

The purpose of this study was to investigate the eco-physiological adaptation of indigenous woody species to their habitats in karst areas of southwestern China. Two contrasting forest habitats were studied: a degraded habitat in Daxiagu and a well-developed habitat in Tianlongshan, and the eco-physiological characteristics of the trees were measured for three growth seasons. Photosynthetic rate (Pn), stomatal conductance (gs), and transpiration rate (Tr) of the tree species in Daxiagu were 2-3 times higher than those in Tianlongshan under ambient conditions. However, this habitat effect was not significant when measurements were taken under controlled conditions. Under controlled conditions, Pn, gs, and Tr of the deciduous species were markedly higher than those for the evergreen species. Habitat had no significant effect on water use efficiency (WUE) or photochemical characteristics of PSII. The stomatal sensitivity of woody species in the degraded habitat was much higher than that in the well-developed habitat. Similarly, the leaf total nitrogen (N) and phosphorus (P) contents expressed on the basis of either dry mass or leaf area were also much higher in Daxiagu than they were in Tianlongshan. The mass-based leaf total N content of deciduous species was much higher than that of evergreen species, while leaf area-based total N and P contents of evergreens were significantly higher than those of deciduous species. The photosynthetic nitrogen- and phosphorus-use efficiencies (PNUE and PPUE) of deciduous species were much higher than those of evergreens. Further, the PPUE of the woody species in Tianlongshan was much higher than that  of the woody species in Daxiagu. The results from three growth seasons imply that the tree species were able to adapt well to their growth habitats. Furthermore, it seems that so-called "temporary drought stress" may not occur, or may not be severe for most woody plants in karst areas of southwestern China.
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http://dx.doi.org/10.12688/f1000research.2-122.v2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3892915PMC
February 2014

Control of nanomorphology in all-polymer solar cells via assembling nanoaggregation in a mixed solution.

ACS Appl Mater Interfaces 2014 Feb 11;6(4):2350-5. Epub 2014 Feb 11.

State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy , 457 Zhongshan Road, Dalian 116023, P. R. China.

The formation of interconnected phase-separated domains on sub-20 nm length scale is a key requirement for all-polymer solar cells (all-PSCs) with high efficiency. Herein, we report the application of crystalline poly(3-hexylthiophene) (P3HT) nanowires via an O-dichlorobenzene/hexane mixed solution blended with poly{(9,9-dioctylfluorenyl-2,7-diyl)-alt-[4,7-bis(3-hexylthiophen-5-yl)-2,1,3-benzothiadiazole]-2',2″-diyl} (F8TBT) for the first time. The nanomorphology of P3HT:F8TBT all-PSCs can be controlled by P3HT nanowires. The improved film morphology leads to enhanced light absorption, exciton dissociation, and charge transport in all-PSCs, as confirmed by ultraviolet-visible absorption spectra, X-ray diffraction, transmission electron microscopy, atomic force microscopy, and time-resolved photoluminescence spectra. The P3HT nanowire:F8TBT all-PSCs could achieve a power conversion efficiency of 1.87% and a Voc of 1.35 V, both of which are the highest values for P3HT:F8TBT all-PSCs. This work demonstrates that the semiconductor nanowires fabricated by the mixed solvents method is an efficient solution process approach to controlling the nanomorphology of all-PSCs.
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http://dx.doi.org/10.1021/am404483gDOI Listing
February 2014

A novel proteinase, SNOWY COTYLEDON4, is required for photosynthetic acclimation to higher light intensities in Arabidopsis.

Plant Physiol 2013 Oct 12;163(2):732-45. Epub 2013 Aug 12.

Australian Research Council Centre of Excellence in Plant Energy Biology , Australian National University Canberra, Acton, Australian Capital Territory 0200, Australia;

Excess light can have a negative impact on photosynthesis; thus, plants have evolved many different ways to adapt to different light conditions to both optimize energy use and avoid damage caused by excess light. Analysis of the Arabidopsis (Arabidopsis thaliana) mutant snowy cotyledon4 (sco4) revealed a mutation in a chloroplast-targeted protein that shares limited homology with CaaX-type endopeptidases. The SCO4 protein possesses an important function in photosynthesis and development, with point mutations rendering the seedlings and adult plants susceptible to photooxidative stress. The sco4 mutation impairs the acclimation of chloroplasts and their photosystems to excess light, evidenced in a reduction in photosystem I function, decreased linear electron transfer, yet increased nonphotochemical quenching. SCO4 is localized to the chloroplasts, which suggests the existence of an unreported type of protein modification within this organelle. Phylogenetic and yeast complementation analyses of SCO4-like proteins reveal that SCO4 is a member of an unknown group of higher plant-specific proteinases quite distinct from the well-described CaaX-type endopeptidases RAS Converting Enzyme1 (RCE1) and zinc metallopeptidase STE24 and lacks canonical CaaX activity. Therefore, we hypothesize that SCO4 is a novel endopeptidase required for critical protein modifications within chloroplasts, influencing the function of proteins involved in photosynthesis required for tolerance to excess light.
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http://dx.doi.org/10.1104/pp.113.216036DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3793054PMC
October 2013

Photosynthetic light and CO2 utilization and C4 traits of two novel super-rice hybrids.

J Plant Physiol 2006 Mar 2;163(5):529-37. Epub 2005 Aug 2.

Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.

Characteristics of photosynthetic light and CO2 use efficiency from seedling to heading stage, and C4 pathway enzyme activities in both flag leaves and lemma were compared between two newly developed super-rice hybrids (Oryza sativa L.), Liangyoupeijiu and Hua-an 3, and a traditional rice hybrid, Shanyou 63. At seedling and tillering stages, Liangyoupeijiu and Hua-an 3 had higher net photosynthetic rates (Pn) and light saturated assimilation rates (Asat) than did Shanyou 63, at both normal (360 micromol mol(-1)) and doubled (720 micromol mol(-1)) CO2 concentrations. At the heading stage, the flag leaves of all three rice hybrids had similar Pn and Asat. However, the two super-rice hybrids had higher apparent quantum yield (AQY) and carboxylation efficiency (CE) during all three typical developmental stages, and higher quantum yield of CO2 fixation (PhiCO2) at the tillering and heading stages. In addition, Liangyoupeijiu showed significantly higher activities of the C(4) pathway enzymes in both flag leaves and lemmas than did Shanyou 63. As a result, flag leaves of the two super-rice hybrids had higher Pn at morning, noontime and late afternoon during the daily cycle. Since most of the grain yield of rice comes from the photosynthesis of flag leaves, the similar Asat and much higher AQY, CE and PhiCO2 at heading stage of the two super-rice hybrids indicates that higher photosynthetic efficiency rather than higher photosynthetic capacity may be the primary factor contributing to their higher grain yields.
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http://dx.doi.org/10.1016/j.jplph.2005.04.035DOI Listing
March 2006

[Global consequences and control strategies of biological invasion].

Ying Yong Sheng Tai Xue Bao 2003 Oct;14(10):1795-8

Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.

Biological invasion is a worldwide ecological phenomenon, but its mechanism is still not very clear. Invasive species give impacts on native species and ecosystems through competitions, predations, changing habitats, and dispersing diseases. They pose an increasing threat to the composition and structure of natural communities across the globe. Biological invasion has been greatly damaging the ecological and evolutionary integrity of natural ecosystems, which will weaken the functions of the ecosystems and frequently cause natural disasters. A better understanding of the causes, patterns, predictability, consequences, and management options associated with this threat to biodiversity is necessary to guide managers, policy makers, researchers, and general publics. Biological invasion also causes huge economic losses, and 137 billion dollar losses per year from biological invasion were estimated in USA. Invasive diseases impair human health and kill thousands and thousands of people, and invasive bacteria lead to so serious social panic and turbulence that people could feel uneasy even when eating and sleeping. Biological invasion largely decreases global biodiversity, which will threaten the survival and development of our descendants. Three steps are used in prevention and control of biological invasions. Comprehensive quarantine is the most effective way to prevent exotic invasion by accident. Ecological evaluation and monitoring is helpful to avoid disasters from species introduction. Physical methods, chemical approaches and biological controls are used to eradicate and control the spread of invaded species. Before biological controls are chosen, risk analysis of controlling organism is needed. Ideally, there should be both pre-eradication assessment to tailor removal to avoid unwanted ecological effects and post-removal assessment of eradication effects on both the target organism and the invaded ecosystem.
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October 2003
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