Wang J.-G.,National Taiwan University |
Chen C.-H.,National Taiwan University |
Chien C.-T.,Taiwan Forestry Research Institute |
Hsieh H.-L.,National Taiwan University
Plant Physiology | Year: 2011
FAR-RED INSENSITIVE219 (FIN219) in Arabidopsis (Arabidopsis thaliana) is involved in phytochrome A-mediated far-red (FR) light signaling. Previous genetic studies revealed that FIN219 acts as an extragenic suppressor of CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1). However, the molecular mechanism underlying the suppression of COP1 remains unknown. Here, we used a transgenic approach to study the regulation of COP1 by FIN219. Transgenic seedlings containing ectopic expression of the FIN219 amino (N)-terminal domain in wild-type Columbia (named NCox for the expression of the N-terminal coiled-coil domain and NTox for the N-terminal 300-amino acid region) exhibited a dominant-negative long-hypocotyl phenotype under FR light, reflected as reduced photomorphogenic responses and altered levels of COP1 and ELONGATED HYPOCOTYL5 (HY5). Yeast two-hybrid, pull-down, and bimolecular fluorescence complementation assays revealed that FIN219 could interact with the WD-40 domain of COP1 and with its N-terminal coiled-coil domain through its carboxyl-terminal domain. Further in vivo coimmunoprecipitation study confirms that FIN219 interacts with COP1 under continuous FR light. Studies of the double mutant fin219-2/cop1-6 indicated that HY5 stability requires FIN219 under darkness and FR light. Moreover, FIN219 levels positively regulated by phytochrome A can modulate the subcellular location of COP1 and are differentially regulated by various fluence rates of FR light.We conclude that the dominant-negative long-hypocotyl phenotype conferred by NCox and NTox in a wild-type background was caused by the misregulation of COP1 binding with the carboxyl terminus of FIN219. Our data provide a critical mechanism controlling the key repressor COP1 in response to FR light. © 2011 American Society of Plant Biologists.
Lasky J.R.,University of Texas at Austin |
Sun I.-F.,National Dong Hwa University |
Su S.-H.,Taiwan Forestry Research Institute |
Chen Z.-S.,National Taiwan University |
Keitt T.H.,University of Texas at Austin
Journal of Ecology | Year: 2013
Individual performance is a function of an individual's traits and its environment. This function, known as an environmental filter, varies in space and affects community composition. However, filters are poorly characterized because dispersal patterns can obscure environmental effects, and few studies utilize longitudinal data linking individual performance to environment. We model the effects of environmental filters on demographic rates of nearly all tree species (99) in a 25-ha subtropical rain forest plot. We develop a hierarchical Bayesian model of environmental filtering, drawing inspiration from classic studies of intraspecific natural selection. We characterize the specific environmental gradients and trait axes most important in filtering of demographic rates across species. We found that stronger filtering along a given trait axis corresponded to less spatial variation in the value of favoured traits. Environmental gradients associated with filtering were different for growth versus survivorship. Species maximum height was under the strongest filtering for growth, with shorter species favoured on convex ridges. Shorter stature species may be favoured on ridges because trees on ridges experience higher wind damage and lower soil moisture. Wood density filtering had the strongest effects on survival. Steep slopes and high available P in the soil favoured species with low-density wood. Such sites may be favourable for fast-growing species that exploit resource-rich environments. Synthesis: We characterized trait-mediated environmental filters that may underlie spatial niche differentiation and life-history trade-offs, which can promote species coexistence. Filtering along trait axes with the strongest effects on local community composition, that is, traits with the strongest filtering, may necessarily have a weaker potential to promote species coexistence across the plot. The weak spatial variation in filters with strong effects on demography may result from long-term processes affecting the species pool that favour habitat generalist strategies. © 2013 The Authors. Journal of Ecology © 2013 British Ecological Society.
Kuo L.-Y.,National Taiwan University |
Li F.-W.,National Taiwan University |
Li F.-W.,Duke University |
Chiou W.-L.,Taiwan Forestry Research Institute |
Wang C.-N.,National Taiwan University
Molecular Phylogenetics and Evolution | Year: 2011
MatK, the only maturase gene in the land plant plastid genome, is a very popular phylogenetic marker that has been extensively applied in reconstructing angiosperm phylogeny. However, the use of matK in fern phylogeny is largely unknown, due to difficulties with amplification: ferns have lost the flanking trnK exons, typically the region used for designing stable priming sites. We developed primers that are either universal or lineage-specific that successfully amplify matK across all fern families. To evaluate whether matK is as powerful a phylogenetic marker in ferns as in angiosperms, we compared its sequence characteristics and phylogenetic performance to those of rbcL and atpA. Among these three genes, matK has the highest variability and substitution evenness, yet shows the least homoplasy. Most importantly, applying matK in fern phylogenetics better resolved relationships among families, especially within eupolypods I and II. Here we demonstrate the power of matK for fern phylogenetic reconstruction, as well as provide primers and extensive sequence data that will greatly facilitate future evolutionary studies of ferns. © 2011 Elsevier Inc.
Porter J.H.,University of Virginia |
Hanson P.C.,University of Wisconsin - Madison |
Lin C.-C.,Taiwan Forestry Research Institute
Trends in Ecology and Evolution | Year: 2012
Developments in sensor design, electronics, computer technology and networking have converged to provide new ways of collecting environmental data at rates hitherto impossible to achieve. To translate this 'data deluge' into scientific knowledge requires comparable advances in our ability to integrate, process and analyze massive data sets. We review the experience of one large project in ingesting and analyzing sensor data from global lakes and provide a synopsis of innovative approaches being used to confront the information management and analytical challenges posed by massive volumes of data. © 2011 Elsevier Ltd.
Hsu T.-C.,Taiwan Forestry Research Institute |
Kuo C.-M.,National Taiwan University
Annales Botanici Fennici | Year: 2011
A new species, Gastrodia albida T.C. Hsu & C.M. Kuo (Orchidaceae), is described and illustrated from Taiwan. Gastrodia albida is closely related to G. theana but differs by having a perianth tube indistincy striate outside, larger and oblong-ovate petals, narrower lip with truncate base, and by the absence of a rostellum. Gastrodia albida is predicted to be self-pollinated based on the morphological and ecological features. © Finnish Zoological and Botanical Publishing Board.
Chen J.-H.,National Taiwan University |
Jiang H.-W.,National Taiwan University |
Hsieh E.-J.,National Taiwan University |
Chen H.-Y.,National Taiwan University |
And 3 more authors.
Plant Physiology | Year: 2012
Although glutathione S-transferases (GSTs) are thought to play major roles in oxidative stress metabolism, little is known about the regulatory functions of GSTs. We have reported that Arabidopsis (Arabidopsis thaliana) GLUTATHIONE S-TRANSFERASE U17 (AtGSTU17; At1g10370) participates in light signaling and might modulate various aspects of development by affecting glutathione (GSH) pools via a coordinated regulation with phytochrome A. Here, we provide further evidence to support a negative role of AtGSTU17 in drought and salt stress tolerance. When AtGSTU17 was mutated, plants were more tolerant to drought and salt stresses compared with wild-type plants. In addition, atgstu17 accumulated higher levels of GSH and abscisic acid (ABA) and exhibited hyposensitivity to ABA during seed germination, smaller stomatal apertures, a lower transpiration rate, better development of primary and lateral root systems, and longer vegetative growth. To explore how atgstu17 accumulated higher ABA content, we grew wild-type plants in the solution containing GSH and found that they accumulated ABA to a higher extent than plants grown in the absence of GSH, and they also exhibited the atgstu17 phenotypes. Wild-type plants treated with GSH also demonstrated more tolerance to drought and salt stresses. Furthermore, the effect of GSH on root patterning and drought tolerance was confirmed by growing the atgstu17 in solution containing L-buthionine-(S,R)- sulfoximine, a specific inhibitor of GSH biosynthesis. In conclusion, the atgstu17 phenotype can be explained by the combined effect of GSH and ABA. We propose a role of AtGSTU17 in adaptive responses to drought and salt stresses by functioning as a negative component of stress-mediated signal transduction pathways. © 2011 American Society of Plant Biologists. All Rights Reserved.
Rothfels C.J.,Duke University |
Larsson A.,Uppsala University |
Kuo L.-Y.,National Taiwan University |
Korall P.,Uppsala University |
And 2 more authors.
Systematic Biology | Year: 2012
Backbone relationships within the large eupolypod II clade, which includes nearly a third of extant fern species, have resisted elucidation by both molecular and morphological data. Earlier studies suggest that much of the phylogenetic intractability of this group is due to three factors: (i) a long root that reduces apparent levels of support in the ingroup; (ii) long ingroup branches subtended by a series of very short backbone internodes (the "ancient rapid radiation" model); and (iii) significantly heterogeneous lineage-specific rates of substitution. To resolve the eupolypod II phylogeny, with a particular emphasis on the backbone internodes, we assembled a data set of five plastid loci (atpA, atpB, matK, rbcL, and trnG-R) from a sample of 81 accessions selected to capture the deepest divergences in the clade. We then evaluated our phylogenetic hypothesis against potential confounding factors, including those induced by rooting, ancient rapid radiation, rate heterogeneity, and the Bayesian star-tree paradox artifact. While the strong support we inferred for the backbone relationships proved robust to these potential problems, their investigation revealed unexpected model-mediated impacts of outgroup composition, divergent effects of methods for countering the star-tree paradox artifact, and gave no support to concerns about the applicability of the unrooted model to data sets with heterogeneous lineage-specific rates of substitution. This study is among few to investigate these factors with empirical data, and the first to compare the performance of the two primary methods for overcoming the Bayesian star-tree paradox artifact. Among the significant phylogenetic results is the near-complete support along the eupolypod II backbone, the demonstrated paraphyly of Woodsiaceae as currently circumscribed, and the well-supported placement of the enigmatic genera Homalosorus, Diplaziopsis, and Woodsia. © 2012 The Author(s).
Lin Y.-C.,Tunghai University |
Chang L.-W.,Taiwan Forestry Research Institute |
Yang K.-C.,Providence University |
Wang H.-H.,Taiwan Forestry Research Institute |
Sun I.-F.,Tunghai University
Oecologia | Year: 2011
Understanding processes underlying spatial distribution of tree species is fundamental to studying species coexistence and diversity. This study modeled point patterns of tree distribution, expressed by Cartesian coordinates of individual trees within a mapped forest stand, for the purpose of identifying processes that may generate spatial patterns of tree communities. We used four primary point pattern processes (homogeneous Poisson process, inhomogeneous Poisson process, homogeneous Thomas process, and inhomogeneous Thomas process) to model tree distribution in two stem-mapped forests in Taiwan, Republic of China. These four models simulate spatial processes of habitat association and seed dispersal, allowing us to evaluate the potential contribution of habitat heterogeneity and dispersal limitation to the formation of spatial patterns of tree species. The results showed that the inhomogeneous Thomas process was the best fit model and described most of the species studied, suggesting that spatial patterns of tree species might be formed by the joint effects of habitat associations and dispersal limitation. The homogeneous Thomas process that models the effect of dispersal limitation was the second best model. We also found that the best fit models could be predicted by species attributes, including species abundance and dispersal mode. The significant traits, however, differed between the two study plots and demonstrated site-specific patterns. This study indicated that the interactive operation of niche-based (habitat heterogeneity) and neutral-based (dispersal limitation) may be important in generating spatial patterns of tree species in forest communities. © 2010 Springer-Verlag.
Wang Y.-C.,Chinese Culture University |
Lin J.-C.,Taiwan Forestry Research Institute
Forest Policy and Economics | Year: 2012
Air pollution control is an important aspect of environmental protection in Taiwan. In 1995, Taiwan's government began, via afforestation, to establish air quality enhancement zones (AQEZs) in order to promote multiple environmental benefits, including improved air quality, increased carbon sequestration, and enhanced environmental quality of life. In 2010, there were over 504 such zones. In addition to providing urban forests and green spaces, tree growth in AQEZs can sequester atmospheric carbon dioxide and, by shading and evapotranspiration, reduce energy demand and increase soil storage of organic carbon. In addition, afforestation can offset the carbon footprint of the world's population and is one of the best approaches to implementing carbon neutrality. The purpose of this study was to analyze the carbon reduction benefits of afforested AQEZs. Investigations of 48 AQEZs showed (1) a high diversity of trees planted (168 species), (2) an average density of trees of 1142/ha, (3) a forest timber volume of 23.92m 3/ha, lower than in standard plantations, (4) a carbon storage capacity of 9.25tons/ha, and (5) average annual carbon sequestration of 1.34ton-C/ha/yr. Carbon sequestration by AQEZs in Taiwan, although not remarkably high, is nevertheless, along with other ecosystem services provided by AQEZs, a significant and direct benefit to the urban public. This study provides a reliable basis of measureable results with which decision makers can evaluate benefits of urban forest carbon sequestration. © 2012 Elsevier B.V.
Lu S.-Y.,Taiwan Forestry Research Institute
Taiwan Journal of Forest Science | Year: 2016
Rainfall characteristics including types, regimes, frequency behaviors, long-term changes, and design storm distributions were analyzed for the area of the Hengchun Peninsula in this study. The mechanism of rainfall in the study area can mainly be classified as frontal rain, thunderstorms, and typhoon rain. Each of these mechanisms dominates the type and characteristics of rainfall. Rainfall is extremely unevenly distributed in the annual cycle. About 91.03% of the rainfall is concentrated in the period from May to October (wet season), and the rest (8.97%) is in the period from November to April (dry season). There was a total of 121.7 days on average which had at least 0.1 mm d-1 rainfall in the yearly cycle of the study area. The percentage of rainy days in the wet season of the total rainy days in a year was 71.41%, and that of the dry season was 28.59%. This phenomenon indicates that rainfall in the wet season is relatively strong when it occurs, and that in the dry season is usually in smaller amounts. Annual and wet season rainfall totals have significantly increased in the last 4 decades. Annual rainfall has increased about 14.6 mm decades-1 and that in the wet season has increased about 12.8 mm decades-1. However, the rainfall amount in the dry season has slightly decreased at a rate of -2.5 mm decades-1. This phenomenon indicates that there is an increasing trend of rainfall, but the increase is mainly in the wet season. Long-term changes of rainfall-days show a steadily decreasing tendency. Rainfall-days were obviously reduced after 1990. Annual rainfall-days showed the largest declining rate, while rainy days in the dry season showed the least decline. The number of days with a rainfall amount exceeding 30 mm showed an increasing tendency in both the wet and dry seasons. In addition, the Extreme Value Type I distribution was used in this study to estimate magnitudes of 2-, 5-, 10-, 25-, 50-, and 100-year return intervals for 10-min, 1-h, 6-h and 24-h rainfall events. Design storm distributions for 3, 6, and 12 hours were also been analyzed. Results of the design storm analysis combined with those of the frequency analysis can provide a reference for designing hydraulic structures and water control works on the Hengchun Peninsula.