Habitat and Demography of Understory Trees in Mixed Species Hardwood Forests in Northern Florida, United States of America.

Temperate mixed-species hardwood forests of northern Florida, USA, contain a high diversity of understory tree species, some of which have been hypothesized to require disturbance (e.g., hurricanes and/or treefall gaps). Taxus floridana is a rare understory conifer endemic to midslopes of ravines of the Apalachicola River Bluffs, and is found primarily on north-facing slopes. Vegetation sampling in the southern portion of T. floridana\u27s range revealed the presence of an upslope oak-hickory community of suggested recent origin, and higher densities of American beech (Fagus grandifolia ), southern magnolia (Magnolia grandiflora), and evergreen understory trees on north-facing midslopes with T. floridana than on randomly chosen north-facing midslopes. Thus, T. floridana presently exhibits high habitat specificity to restricted areas of north-facing midslopes. The status of T. floridana was investigated by acquiring demographic data on stem recruitment, survival, and growth, in three different populations (Rock Creek, Long Branch, and Beaverdam Creek) over four years. Seedling recruitment was temporally variable; seedling recruitment was also characterized by an episode in 1996 that was approximately ten-fold higher than in the proceeding years. Fates of seedlings varied both spatially and temporally, while fates of non-seedling stems with small diameters varied spatially. Growth of individual stems was similar in all populations sampled. Periodic matrix models incorporating such demographic data predicted declining growth rates for all sampled populations of T. floridana . This is consistent with recent anthropogenic changes in T. floridana\u27s habitat, and/or its prolonged existence in low quality habitats. Annual episodic regeneration essentially did not influence population growth rates. Increasing the survival of juvenile stems may help promote net positive population growth in such rare species. Finally, recruitment of Ostrya virginiana and Carpinus caroliniana, two more common understory species was examined following Hurricane Kate in 1985 using long-term data from Woodyard Hammock in north Florida. Post-hurricane recruitment was equally high in gaps of different ages (i.e., different histories), and was higher than in areas under closed canopy. The presence of a juvenile sapling bank before and at the time of Kate may be responsible for their present dominance in the understory stratum in Woodyard Hammock

Conserving slow-growing, long-lived tree species: Input from the demography of a rare understory conifer, Taxus floridana

Although land preservation and promotion of successful regeneration are important conservation actions, their ability to increase population growth rates of slow-growing, long-lived trees is limited. We investigated the demography of Taxus floridana Nutt., a rare understory conifer, in three populations in different ravine forests spanning its entire geographic range along the Apalachicola River Bluffs in northern Florida (U.S.A.). We examined spatial and temporal patterns in demographic parameters and projected population growth rates by using four years of data on the recruitment and survival of seedlings and established stems, and on diameter growth from cross-sections of dead stems. All populations experienced a roughly 10-fold increase in seedling recruitment in 1996 compared with other years. The fates of seedlings and stems between 8 and 16 mm differed among populations. The fates of stems in two other size classes (the 2- to 4-mm class and the 4- to 8-mm class) differed among both populations and years. Individual stems in all populations exhibited similarly slow growth rates. Stochastic matrix models projected declines in all populations. Stochastic matrix analysis revealed the high elasticity of a measure of stochastic population growth rate to perturbations in the stasis of large reproductive stems for all populations. Additional analyses also indicated that occasional episodes of high recruitment do not greatly affect population growth rates. Conservation efforts directed at long-lived, slow-growing rare plants like Taxus floridana should both protect established reproductive individuals and further enhance survival of individuals in other life-history stages, such as juveniles, that often do not appear to contribute greatly to population growth rates

Advances in biotechnology and genomics of switchgrass

Switchgrass (Panicum virgatum L.) is a C4 perennial warm season grass indigenous to the North American tallgrass prairie. A number of its natural and agronomic traits, including adaptation to a wide geographical distribution, low nutrient requirements and production costs, high water use efficiency, high biomass potential, ease of harvesting, and potential for carbon storage, make it an attractive dedicated biomass crop for biofuel production. We believe that genetic improvements using biotechnology will be important to realize the potential of the biomass and biofuel-related uses of switchgrass. Tissue culture techniques aimed at rapid propagation of switchgrass and genetic transformation protocols have been developed. Rapid progress in genome sequencing and bioinformatics has provided efficient strategies to identify, tag, clone and manipulate many economically-important genes, including those related to higher biomass, saccharification efficiency, and lignin biosynthesis. Application of the best genetic tools should render improved switchgrass that will be more economically and environmentally sustainable as a lignocellulosic bioenergy feedstock

Stand structure and dynamics of sand pine differ between the Florida panhandle and peninsula

Size and age structures of stand populations of numerous tree species exhibit uneven or reverse J-distributions that can persist after non-catastrophic disturbance, especially windstorms. Among disjunct populations of conspecific trees, alternative distributions are also possible and may be attributed to more localized variation in disturbance. Regional differences in structure and demography among disjunct populations of sand pine (Pinus clausa (Chapm. ex Engelm.) Vasey ex Sarg.) in the Florida panhandle and peninsula may result from variation in hurricane regimes associated with each of these populations. We measured size, age, and growth rates of trees from panhandle and peninsula populations and then compiled size and age class distributions. We also characterized hurricanes in both regions over the past century. Size and age structures of panhandle populations were unevenly distributed and exhibited continuous recruitment; peninsula populations were evenly sized and aged and exhibited only periodic recruitment. Since hurricane regimes were similar between regions, historical fire regimes may have been responsible for regional differences in structure of sand pine populations. We hypothesize that fires were locally nonexistent in coastal panhandle populations, while periodic high intensity fires occurred in peninsula populations over the past century. Such differences in local fire regimes could have resulted in the absence of hurricane effects in the peninsula. Increased intensity of hurricanes in the panhandle and current fire suppression patterns in the peninsula may shift characteristics of sand pine stands in both regions. © 2007 Springer Science+Business Media B.V

Sensitivity of a real-time PCR method for the detection of transgenes in a mixture of transgenic and non-transgenic seeds of papaya (\u3cem\u3eCarica papaya\u3c/em\u3e L.)

Background Genetically engineered (GE) ringspot virus-resistant papaya cultivars ‘Rainbow’ and ‘SunUp’ have been grown in Hawai’i for over 10 years. In Hawai’i, the introduction of GE papayas into regions where non-GE cultivars are grown and where feral non-GE papayas exist have been accompanied with concerns associated with transgene flow. Of particular concern is the possibility of transgenic seeds being found in non-GE papaya fruits via cross-pollination. Development of high-throughput methods to reliably detect the adventitious presence of such transgenic material would benefit both the scientific and regulatory communities. Results We assessed the accuracy of using conventional qualitative polymerase chain reaction (PCR) as well as real-time PCR-based assays to quantify the presence of transgenic DNA from bulk samples of non-GE papaya seeds. In this study, an optimized method of extracting high quality DNA from dry seeds of papaya was standardized. A reliable, sensitive real-time PCR method for detecting and quantifying viral coat protein (cp) transgenes in bulk seed samples utilizing the endogenous papain gene is presented. Quantification range was from 0.01 to 100 ng/μl of GE-papaya DNA template with a detection limit as low as 0.01% (10 pg). To test this system, we simulated transgene flow using known quantities of GE and non-GE DNA and determined that 0.038% (38 pg) GE papaya DNA could be detected using real-time PCR. We also validated this system by extracting DNA from known ratios of GE seeds to non-GE seeds of papaya followed by real-time PCR detection and observed a reliable detection limit of 0.4%. Conclusions This method for the quick and sensitive detection of transgenes in bulked papaya seed lots using conventional as well as real-time PCR-based methods will benefit numerous stakeholders. In particular, this method could be utilized to screen selected fruits from maternal non-GE papaya trees in Hawai’i for the presence of transgenic seed at typical regulatory threshold levels. Incorporation of subtle differences in primers and probes for variations in cp worldwide should allow this method to be utilized elsewhere when and if deregulation of transgenic papaya occurs

Sensitivity of a real-time PCR method for the detection of transgenes in a mixture of transgenic and non-transgenic seeds of papaya (Carica papaya L.)

BACKGROUND: Genetically engineered (GE) ringspot virus-resistant papaya cultivars ‘Rainbow’ and ‘SunUp’ have been grown in Hawai’i for over 10 years. In Hawai’i, the introduction of GE papayas into regions where non-GE cultivars are grown and where feral non-GE papayas exist have been accompanied with concerns associated with transgene flow. Of particular concern is the possibility of transgenic seeds being found in non-GE papaya fruits via cross-pollination. Development of high-throughput methods to reliably detect the adventitious presence of such transgenic material would benefit both the scientific and regulatory communities. RESULTS: We assessed the accuracy of using conventional qualitative polymerase chain reaction (PCR) as well as real-time PCR-based assays to quantify the presence of transgenic DNA from bulk samples of non-GE papaya seeds. In this study, an optimized method of extracting high quality DNA from dry seeds of papaya was standardized. A reliable, sensitive real-time PCR method for detecting and quantifying viral coat protein (cp) transgenes in bulk seed samples utilizing the endogenous papain gene is presented. Quantification range was from 0.01 to 100 ng/μl of GE-papaya DNA template with a detection limit as low as 0.01% (10 pg). To test this system, we simulated transgene flow using known quantities of GE and non-GE DNA and determined that 0.038% (38 pg) GE papaya DNA could be detected using real-time PCR. We also validated this system by extracting DNA from known ratios of GE seeds to non-GE seeds of papaya followed by real-time PCR detection and observed a reliable detection limit of 0.4%. CONCLUSIONS: This method for the quick and sensitive detection of transgenes in bulked papaya seed lots using conventional as well as real-time PCR-based methods will benefit numerous stakeholders. In particular, this method could be utilized to screen selected fruits from maternal non-GE papaya trees in Hawai’i for the presence of transgenic seed at typical regulatory threshold levels. Incorporation of subtle differences in primers and probes for variations in cp worldwide should allow this method to be utilized elsewhere when and if deregulation of transgenic papaya occurs

Implementation of Balanced Scorecard Method in an Engineering Company

Import 23/08/2017Cílem diplomové práce je navrhnout konkrétní formu implementace Balanced Scorecard do systému řízení pro podnik PMB – ZOS, s.r.o., která povede ke zvýšení výkonnosti a konkurenceschopnosti této společnosti. V části teoreticko – metodologické budou definovány principy metody Balanced Scorecard zahrnující specifikaci jednotlivých perspektiv, popis implementace včetně omezení a bariér aplikace této metody. Praktická část se pak již bude zabývat provedením analýz u jednotlivých čtyř perspektiv a následným vytvořením konkrétního návrhu implementace dané metody do podniku. Závěr práce budou tvořit návrhy a doporučení pro podnik včetně vyčíslení nákladů na zavedení této metody.The aim of the diploma thesis is to propose a specific form of implementation of the Balanced Scorecard management system for the company PMB - ZOS, s.r.o., which can promote the increasing of the efficiency and competitiveness of the company. In the theoretical - methodological part will be defined principles of the Balanced Scorecard method comprising the specification of individual perspectives, including description of implementation barriers and limitations of application of this method. The practical part will be engaged in performance analyzes for each of the four perspectives and the subsequent creation of a specific design of the implementation of the method for this company. The final part of this diploma thesis will include proposals and recommendations for this company, including costings for implementation of the method.152 - Katedra podnikohospodářskávýborn

The master data file for AJB-D-18-00217R1

This is a .xlsx file containing the raw and metadata from our study. The first sheet (AJB-D-18-00217R1_Field_2016_raw) contains field observations of ant-seed dispersal distances and rates for endemic-widespread Trillium pairs across 9 study sites. The second sheet (AJB-D-18-00217R1_Cafeteria_raw) contains data from laboratory cafeteria experiments of ant preference. The third sheet (Cafeteria_metadata) contains metadata on the cafeteria raw data. The fourth sheet (Field_metadata) contains metadata on the field raw data

Data from: Overall seed dispersal effectiveness is lower in endemic Trillium species than in their widespread congeners

PREMISE OF THE STUDY: Comparing ecological attributes of endemic species with related, widespread species can reveal differences accounting for rarity. Forests of the southeastern US are home to many range-restricted endemic and widespread species of Trillium, a genus of ant-dispersed herbs. Evidence suggests that aspects of seed-related life history stages are often correlated with plant rarity, but few studies have tested whether the process of seed dispersal differs for endemic and widespread species. To address this question, we compare aspects of seed dispersal effectiveness (SDE) for three sympatric widespread-endemic Trillium species pairs. METHODS: We observed ant seed dispersal for Trillium species pairs at eight sites, recorded numbers of seeds dispersed and dispersal distances, and described disperser interactions. To test disperser preference, we presented seeds of each pair to captive colonies of Aphaenogaster picea, a keystone disperser. Seeds were assigned scores based on worker behavior, and we recorded proportions of seeds dispersed after 60 minutes and 24 hours. KEY RESULTS: Field observations yielded some significant within-pair differences. Ants dispersed more seeds of widespread species for all pairs, although dispersal distances did not differ. In laboratory experiments, after 24 hours, ants dispersed more seeds of widespread species into nests. CONCLUSIONS: Endemic Trillium species exhibited lower overall SDE than their widespread congeners. These findings add to the list of ecological and demographic challenges that face endemic plants when compared to common congeners. Lower SDE may negatively impact reproductive rates and the colonization of new habitats, which may contribute to patterns of endemism. If you would like your personal information to be removed from the database, please contact the publication office