Life Sciences Commons^™

The Effect Of Temperature On Seed Quality And Quantity In Crosses Between European (Populus Tremula) And Hybrid Aspens (P. Tremula X P. Tremuloides), L. Koviuranta, T. Latva-Karjanmaa, P. Pulkkinen

Aspen Bibliography

Hybrid aspen (Populus tremula L. Populus tremuloides Michx.) plantations are expanding in Fennoscandia and the Baltic countries; however, the possible effects of plantations on the native European aspen (P. tremula) and the level of gene flow between European and hybrid aspen have not been investigated. We studied seed quantity and quality in intraspecific and interspecific crosses of the European and hybrid aspens over a two year period. In order to study whether elevated temperatures due to climate change would benefit the species differently, we performed the crosses in different temperatures. In both years, interspecific crosses produced more seeds with higher …

Bmp Planning To Address Urban Runoff: Plaster Creek Watershed Sustain Pilot, Tetra Tech, Inc.

Watershed Reports

The Plaster Creek watershed is tributary to the Grand River in west Michigan. Plaster Creek is one of several impaired streams in this area, located in metropolitan Grand Rapids. There are several listed impairments for the Creek including 1) other indigenous aquatic life and wildlife, 2) warm water fishery, and 3) total and partial body contact recreation. Total maximum daily load (TMDL) studies were completed in 2002 for biota and E. coli to address the listed impairments. In 2008, a watershed management plan (WMP) was developed which outlines an implementation plan for water quality improvement in the watershed. This pilot …

Effect Of Muscle Length On Cross-Bridge Kinetics In Intact Cardiac Trabeculae At Body Temperature, Nima Milani-Nejad, Ying Xu, Jonathan P. Davis, Kenneth S. Campbell, Paul M. L. Janssen

Physiology Faculty Publications

Dynamic force generation in cardiac muscle, which determines cardiac pumping activity, depends on both the number of sarcomeric cross-bridges and on their cycling kinetics. The Frank–Starling mechanism dictates that cardiac force development increases with increasing cardiac muscle length (corresponding to increased ventricular volume). It is, however, unclear to what extent this increase in cardiac muscle length affects the rate of cross-bridge cycling. Previous studies using permeabilized cardiac preparations, sub-physiological temperatures, or both have obtained conflicting results. Here, we developed a protocol that allowed us to reliably and reproducibly measure the rate of tension redevelopment (k_tr; which depends …

Promoting Amphibian Conservation Through The College Classroom: Detection Of Batrachochytrium Dendrobatidis Among Local Amphibians, Julie Wunder, Noel Lampazzi, Kelsey Acre, Nicholas Bent, Sadie Canter, Alexandra Chapman, Margaret Davies, David Kashan, Jonathan Keiley, Rachel Macintyre, Tamara Milton, Kara Weichler, Matthew Wilson, Mizuki Takahashi

Faculty Journal Articles

Many global amphibian declines have been linked to the fungal pathogen Batrachochytrium dendrobatidis (Bd). The knowledge on Bd distribution provides a fundamental basis for amphibian conservation planning. Yet, such Bd distribution information is currently insufficient, in particular at a regional scale. The college classroom provides an excellent opportunity to expand the knowledge of Bd distribution. Here we provide an example of such research projects to detect Bd prevalence among local amphibians in a college course setting and present the results of work conducted in central Pennsylvania, USA. We collected toe clips and conducted PCR assays of six species, …

Molecularly Imprinted Polymer Technology: A Powerful, Generic, Facile And Cost Effective Alternative For Enantio-Recognition And Separation: A Glance At Advances And Applications, Jyn Philip, Dms Mosha

Tanzania Journal of Science

The emerging Molecularly Imprinted Polymer (MIP) technology has yielded proof of concept, harnessing nature’s fundamentals to yield recognition receptor mimics from the miniaturized basics, borrowing on the ground rules, but conveniently avoiding the complexity, fragility, instability, costs and ethics of animal based bio-affinity matrices. Thus, the impact of bio-sciences on the future of technology is not via direct use of the molecules, but rather the lessons learned. Molecular imprinting is a powerful specialty representing the generic, cost effective and facile alternative for preparation of synthetic custom-tailored receptors. It achieves this via creation of specific selective recognition sites for a pre-determined …

New Glucopyranosylglyceryl-N-Octenyl Adipate And Bioactivity Of Retro And Condensed Chalcones From Toussaintia Orientalis, Ss Nyandoro, Mhh , Nkunya, Cc Josepha, Jo Odalo, I Sattler

Tanzania Journal of Science

1-(3-β-D-Glucopyranosylglycer-2-yl)-6-N-(oct-2-enyl)-adipate, [orientalin, 1] was isolated as a new metabolite from the polar leaf extracts of Toussaintia orientalis Verdc (Annonaceae), together with the glycoflavonoids afzelin and quercitrin, and the indolidinoids toussaintines A-C. The reversed chalcones 2-hydroxy-3,4,6-trimethoxychalcone (2) and 2-hydroxy-3,4,6- trimethoxydihydrochalcone (3), the condensed chalcone (+)-6a,12a-dihydro-6-phenyl-7-styryl- 6H,7H-[1]benzopyrano[4,3-][l]benzopyran (4), and mixtures of known triterpenoids and steroids were isolated from the less polar extracts of the root and stem bark of the same plant. The structures were established upon detailed analysis of spectroscopic data and other physical parameters. The chalcones exhibited antimicrobial, anti-inflammatory, antiproliferative and cytotoxic activity at varying efficacy levels, the reversed chalcone …

Effects Of Temperature On The Physicochemical Properties Of Traditionally Processed Vegetable Oils And Their Blends, Fn Ngassapa, Ss Nyandoroa, Tr Mwaisaka

Tanzania Journal of Science

The quality and stability of traditionally processed palm, sunflower and sesame oils and their blends as affected by temperature were evaluated by analyzing their physicochemical properties which included acid, saponification, peroxide, iodine values and refractive indices.. The initial quality of traditionally processed oils studied was found to be within the specifications of TZS and Codex requirements. The results further indicate that the quality of both unblended and blended traditionally processed vegetable oils deteriorate significantly at elevated temperatures (p < 0.05). However, the blends showed relatively better quality and stability than the unblended ones whereby the formulations of palm oil (PO) and sesame oil (SSO) appeared to be more stable than those of PO and sunflower oil (SO). This work suggests that blending of traditionally processed PO, SO and SSO improves the quality and stability of these oils.

Comparison Of Chemical Nano Structure, Rheological And Mechanical Properties Of Long Oil Alkyd Resin Synthesized Using Polybasic Acids Catalyst, Ar Ilkhani

Tanzania Journal of Science

In this research, chemical nano structures, rheological and mechanical properties of long oil alkyd resin which was synthesized using different polybasic acid catalysts have been studied. These catalyst were phosphoric acid, 1,2,4-benzene tricarboxylic acid and succinic acid. The new compounds were compared with reference formula of long oil alkyd resin. For this idea, same formula of clear air drying varnishes were prepared based on different long oil resins which have been synthesized using different catalysts and reference long oil alkyd resin. FTIR spectroscopy was employed to investigate the nano chemical structures of the resins and varnishes. The rheological properties of …

Evaluation Of Patterns And Spatial Trends Of Pesticide Residues From Vikuge Farm, Coast Region, Tanzania By Principal Components Analysis, Kf Kilulya, Gs Mhinzi

Tanzania Journal of Science

This paper reports on the analysis of organochlorine pesticides pollution data obtained from samples collected from Vikuge farm, Coast Region, Tanzania between 2000 and 2003 by principal component analysis (PCA). PCA of the data sets for pesticide residues in water, soil and sediments samples from Vikuge has shown that the obsolete pesticides dumped at Vikuge pasture farm for a number of years undergo degradation with time and the distribution pattern of the pesticides in the three environments is similar. Strong outliers were also identified in the data by the use of PCA score plots. Further analysis of the data by …

Composition Of Non Volatile Oils And Antimicrobial Activities Of Extracts From Monanthotaxis Discolor, And An Undescribed Uvariondedron Species, Ds Parmena, Ca Mgina, Cc Joseph

Tanzania Journal of Science

The chemical compositions of non volatile oil extracts from two Annoneceous plant species Monanthotaxis discolor and an undescribed Uvariodendron species which are endemic to Eastern Arc Mountains, Tanzania were determined by GC-MS. The biological activities of extracts and fractionated samples were also determined. Both methanol and dichloromethane extracts of the root bark of M. discolor showed mild antimicrobial activity and had positive brine shrimp test (BST). The BST test for dichloromethane extract of M. discolor root bark were LC50 41.794 μg/ml and that of methanol extract showed LC50 13.560 μg/ml. The petroleum ether and dichloromethane extracts of root bark of …

Polyphenoloxidase And Perioxidase Activity During Open Air Ripening Storage Of Pineapple (Ananas Comosus L.), Mango (Mangifera Indica) And Papaya (Carica Papaya) Fruits Grown In Dar Es Salaam, Tanzania, Oc Othman

Tanzania Journal of Science

Polyphenoloxidase (PPO) and perioxidase (POD), the enzymes responsible for causing browning and change in texture and flavor of fruits and vegetables, were extracted and measured in harvested mature pineapple (Ananas comosus L.), mango (Mangifera indica) (Viringe and Dodo varieties) and papaya (Carica papaya) fruits during off vine, open air, room temperature ripening storage. The initial (at harvest) average PPO activity values in Δ Optical Density (OD) per minute per cm3 of enzyme solution were 0.00074, 0.00083 and 0.0010 for early, mid and late season pineapple fruits respectively. The initial average PPO activity values in ΔOD/min/ cm3 of enzyme solution were …

Status Of Pesticides And Degradation Products In Soil After Clean-Up Of Stockpiles And Treatment With Sodium Hydroxide At A Former Storage Site In Korogwe, Tanzania, Jam Mahugija

Tanzania Journal of Science

The status of pesticide residues in soil samples collected from a former storage site one year after clean-up of stockpiles and treatment with NaOH was investigated. The analytes were extracted from samples by pressurized fluid extraction using n-hexane:acetone (75:25) mixture. Clean-up of extracts was conducted by using silica gel and alumina with 3% H2O and the extracts were eluted with hexane:dichloromethane (1:1). Extra clean-up was performed through C18 SPE cartridges using acetonitrile as the eluting solvent. Labelled internal standards were used for identification and quantification. Analysis of the analytes was performed using a high resolution GC–MS. The dominant contaminants detected …

Activity Of Enzyme Trypsin Immobilized Onto Macroporous Poly(Epoxy-Acrylamide) Cryogel, W Johnson, Ymm Makame

Tanzania Journal of Science

Bovine pancreatic trypsin has been covalently immobilized onto monolithic polyacrylamide cryogels with epoxy functionality (Epoxy-MPAAGs). The covalent immobilization of trypsin onto Epoxy-MPAAGs was achieved through incorporation of ethylenediamine-glutaraldehyde spacers on the cryogels’ surfaces. The immobilization yield and the influence of pH and temperature conditions on the activity of the immobilized trypsin were assessed by using the hydrolysis of a low molecular weight substrate, N-α-benzoyl-D, L-arginine-p-nitroanilide (BAPNA). Optimal pH and temperature values of 9 and 50 °C, respectively, were established for both the immobilized trypsin and the free trypsin. Activity measurements from the native trypsin before immobilization and the residual free …

Electrochemical Behaviour Of Environmentally Friendly Inhibitor Of Aloe Secundiflora Extract In Corrosion Control Of Carbon Steel In Soft Water Media, J Mutasingwa, J Buchweishaija, Jeg Mdoe

Tanzania Journal of Science

Electrochemical behaviour of Aloe secundiflora on carbon steel corrosion control in neutral and aerated soft water solutions have been investigated using electrochemical impedance spectroscopy and Tafel polarization techniques. The investigation was performed at different inhibitor concentrations under static and dynamic conditions using a Rotating Disk Electrode (RDE). The impedance and polarization results revealed that A. Secundiflora could be a potential corrosion inhibitor for carbon steel undergoing corrosion in fresh water medium. It was found that Aloe secundiflora reduces the electrochemical processes taking place on carbon steel undergoing corrosion. The inhibitor efficiency increases with increase in A. Secundiflora concentration and gradually …

Heavy Metal Content In Some Commonly Consumed Vegetables From Kariakoo Market, Dar Es Salaam, Tanzania, Eb Mubofu

Tanzania Journal of Science

This work reports on the levels of cadmium, lead, copper, manganese and zinc in 174 samples from eight varieties of green vegetables (amaranth, Chinese cabbage, cowpea leaves, green pepper, leafy cabbage, lettuce, okra and pumpkin leaf) commonly grown in Dar es Salaam and marketed at Kariakoo, Tanzania. The amount of cadmium and lead ranged between 3-42 and 11-60 μg/kg respectively. The amount of copper, manganese and zinc ranged between 0.35 - 2.12, 1.01 - 7.57, and 1.19 - 6.33 μg/kg respectively. On average consumption pattern, the contribution of these vegetables to the recommended daily intakes (RDI) for cadmium and lead …

(R)-Β-Lysine Modified Elongation Factor P Functions In Translation Elongation, Tammy J. Bullwinkle, S. Betty Zou, Andrei Rajkovic, Steven J. Hersch, Sara Elgamal, Nathaniel Robinson, David Smil, Yuri Bolshan, William Wiley Navarre, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Post-translational modification of bacterial elongation factor P (EF-P) with (R)-β-lysine at a conserved lysine residue activates the protein in vivo and increases puromycin reactivity of the ribosome in vitro. The additional hydroxylation of EF-P at the same lysine residue by the YfcM protein has also recently been described. The roles of modified and unmodified EF-P during different steps in translation, and how this correlates to its physiological role in the cell, have recently been linked to the synthesis of polyproline stretches in proteins. Polysome analysis indicated that EF-P functions in translation elongation, rather than initiation as proposed previously. This was …

Filtering Efficiency And Feeding Mechanisms Of Daphnia Pulex On Microcystis Aeruginosa And Nannochloropsis, Elizabeth Orlowicz

Honors Theses and Capstones

The filtering and feeding rate of Daphnia pulex from the Old Durham Reservoir, Durham, NH, were measured to determine the feeding efficiency on different concentrations of non-toxic Nannochloropsis (Class Eustigmatophyceae) and toxigenic cyanobacteria Microcystis aeruginosa. Direct observations of thoracic appendage beats and post-abdominal rejections were also measured at 5*10⁵ and 10⁶ cells mL^-1 concentrations of Nannochloropsis and M. aeruginosa to examine the feeding mechanisms of the D. pulex. In the presence of increasing Nannochloropsis concentrations, the filtering rates decreased and the feeding rates increased. When exposed to M. aeruginosa, both the filtering and feeding …

Measuring Population Transmission Potential For Hiv: An Alternative Metric Of Transmission Risk In Men Who Have Sex With Men (Msm) In The Us, Colleen F. Kelley, Eli S. Rosenberg, Brandon M. O'Hara, Paula M. Frew, Travis Sanchez, John L. Peterson, Carlos Del Rio, Patrick S. Sullivan

Environmental & Global Health Faculty Research

Background Various metrics for HIV burden and treatment success [e.g. HIV prevalence, community viral load (CVL), population viral load (PVL), percent of HIV-positive persons with undetectable viral load] have important public health limitations for understanding disparities. Methods and Findings Using data from an ongoing HIV incidence cohort of black and white men who have sex with men (MSM), we propose a new metric to measure the prevalence of those at risk of transmitting HIV and illustrate its value. …See full text for complete abstract.

Orofacial Neuropathic Pain Mouse Model Induced By Trigeminal Inflammatory Compression (Tic) Of The Infraorbital Nerve, Fei Ma, Liping Zhang, Danielle Lyons, Karin N. Westlund

Physiology Faculty Publications

BACKGROUND: Trigeminal neuropathic pain attacks can be excruciating for patients, even after being lightly touched. Although there are rodent trigeminal nerve research models to study orofacial pain, few models have been applied to studies in mice. A mouse trigeminal inflammatory compression (TIC) model is introduced here which successfully and reliably promotes vibrissal whisker pad hypersensitivity.

RESULTS: The chronic orofacial neuropathic pain model is induced after surgical placement of chromic gut suture in the infraorbital nerve fissure in the maxillary bone. Slight compression and chemical effects of the chromic gut suture on the portion of the infraorbital nerve contacted cause mild …

Morc2 Signaling Integrates Phosphorylation-Dependent, Atpase-Coupled Chromatin Remodeling During The Dna Damage Response, Da-Qiang Li, Sujit S. Nair, Kazufumi Ohshiro, Anupam Kumar, Vasudha S. Nair, Suresh B. Pakala, Sirigiri Divijendra Natha Reddy, Rajendra P. Gajula, Jeyanthy Eswaran, L. Aravind, Rakesh Kumar

Biochemistry and Molecular Medicine Faculty Publications

Chromatin dynamics play a central role in maintaining genome integrity, but how this is achieved remains largely unknown. Here, we report that microrchidia CW-type zinc finger 2 (MORC2), an uncharacterized protein with a derived PHD finger domain and a conserved GHKL-type ATPase module, is a physiological substrate of p21-activated kinase 1 (PAK1), an important integrator of extracellular signals and nuclear processes. Following DNA damage, MORC2 is phosphorylated on serine 739 in a PAK1-dependent manner, and phosphorylated MORC2 regulates its DNA-dependent ATPase activity to facilitate chromatin remodeling. Moreover, MORC2 associates with chromatin and promotes gamma-H2AX induction in a PAK1 phosphorylation-dependent manner. …

The Posterior Hypothalamus Exerts Opposing Effects On Nociception Via The A7 Catecholamine Cell Group In Rats, Y. Jeong, J. R. Moes, M. Wagner, J. E. Holden

University Faculty Publications and Creative Works

Stimulation of the posterior hypothalamic area (PH) produces antinociception in rats and humans, but the precise mechanisms are unknown. The PH forms anatomical connections with the parabrachial area, which contains the pontine A7 catecholamine cell group, a group of spinally projecting noradrenergic neurons known to produce antinociception in the dorsal horn. The aim of the present study was to determine whether PH-induced antinociception is mediated in part through connections with the A7 cell group in female Sprague-Dawley rats, as measured by the tail flick and foot withdrawal latency. Stimulation of the PH with the cholinergic agonist carbachol (125nmol) produced antinociception …

Forest Regeneration On The Osa Peninsula, Costa Rica, Manette E. Sandor

Master's Theses

Woody species diversity of secondary forest has the potential to converge with that found in old growth forest. This study is the first to examine multiple aspects of species and reproductive trait diversity, and their relationship to each other, across a successional chronosequence. Species richness and species diversity increases with increasing age of forest. Diaspore size and diversity as well as fruit size generally increased with increasing age of forest, but fruit size diversity did not. Abundance of animal-dispersed species increased whereas wind-dispersed species decreased in abundance over succession. Insect-pollinated individuals were most abundant overall. Diaspore diversity, pollination diversity, and …

The Posterior Hypothalamus Exerts Opposing Effects On Nociception Via The A7 Catecholamine Cell Group In Rats, Y. Jeong, J. R. Moes, M. Wagner, J. E. Holden

University Faculty Publications and Creative Works

Stimulation of the posterior hypothalamic area (PH) produces antinociception in rats and humans, but the precise mechanisms are unknown. The PH forms anatomical connections with the parabrachial area, which contains the pontine A7 catecholamine cell group, a group of spinally projecting noradrenergic neurons known to produce antinociception in the dorsal horn. The aim of the present study was to determine whether PH-induced antinociception is mediated in part through connections with the A7 cell group in female Sprague-Dawley rats, as measured by the tail flick and foot withdrawal latency. Stimulation of the PH with the cholinergic agonist carbachol (125nmol) produced antinociception …

Historical And Contemporary Dna Indicate Fisher Decline And Isolation Occurred Prior To The European Settlement Of California, Jody M. Tucker, Michael K. Schwartz, Richard L. Truex, Kristine L. Pilgrim, Fred W. Allendorf

Biological Sciences Faculty Publications

Establishing if species contractions were the result of natural phenomena or human induced landscape changes is essential for managing natural populations. Fishers (Martes pennanti) in California occur in two geographically and genetically isolated populations in the northwestern mountains and southern Sierra Nevada. Their isolation is hypothesized to have resulted from a decline in abundance and distribution associated with European settlement in the 1800s. However, there is little evidence to establish that fisher occupied the area between the two extant populations at that time. We analyzed 10 microsatelliteloci from 275 contemporary and 21 historical fisher samples (1880-1920) to evaluate the demographic …

U.S. Drought Monitor, December 25, 2012, Richard R. Heim Jr.

United States Agricultural Commodities in Drought Archive

Drought map of the United States for December 25, 2012 (12/25/12) plus: United States crop areas experiencing drought (map), an approximate percentage of crop located in drought by state (bar graph), and the percentage of crop area located in drought during the past 52 weeks (line graph) for hay, cattle, and winter wheat.

The Impact Of Coastal Phytoplankton Blooms On Ocean-Atmosphere Thermal Energy Exchange: Evidence From A Two-Way Coupled Numerical Modeling System, Jason K. Jolliff, Travis A. Smith, Charlie N. Barron, Sergio Derada, Stephanie C. Anderson, Richard W. Gould, Robert A. Arnone

Faculty Publications

A set of sensitivity experiments are performed with a two-way coupled and nested ocean-atmosphere forecasting system in order to deconvolve how dense phytoplankton stocks in a coastal embayment may impact thermal energy exchange processes. Monterey Bay simulations parameterizing solar shortwave transparency in the surface ocean as an invariant oligotrophic oceanic water type estimate consistently colder sea surface temperature (SST) than simulations utilizing more realistic, spatially varying shortwave attenuation terms based on satellite estimates of surface algal pigment concentration. These SST differences lead to an similar to 88% increase in the cumulative turbulent thermal energy transfer from the ocean to the …

Evaluasi Berat Badan Tidak Naik Pada Bayi Di Bawah Dua Tahun Warga Miskin Setelah Pemberian Mp-Asi, Ratri Ciptaningtyas, Arif Sumantri, M. Arbi Ramadhan

Kesmas

Program Pemberian Makanan Pendamping ASI (MP-ASI) berupa bubur untuk 6-11 bulan dan biskuit untuk 12-24 bulan dan bertujuan untuk meningkatkan status gizi pada anak, terutama pada keluarga miskin. Tujuan penelitian ini mengevaluasi berbagai faktor yang memengaruhi berat badan tidak naik pada baduta keluarga miskin setelah pemberian program MP-ASI kementerian kesehatan. Penelitian ini dilakukan pada 82 ibu baduta yang menerima MP-ASI dengan desain studi kasus kontrol menggunakan data primer dan sekunder. Analisis dilakukan dengan regresi multivariat. Hasil penelitian menunjukkan hubungan antara berat badan tidak naik dengan ASI eksklusif (OR = 3,48; IK 95% = 1,38-8,80), pemberian MP-ASI kementerian kesehatan (OR = …

Understanding Affordances: History And Contemporary Development Of Gibson’S Central Concept, Dobromir Dotov, Lin Nie, Matthieu M. De Wit

Journal Articles

Gibson developed the affordance concept to complement his theory of direct perception that stands in sharp contrast with the prevalent inferential theories of perception. A comparison of the two approaches shows that the distinction between them also has an ontological aspect. We trace the history and newer formalizations of the notion of affordance and discuss some competing opinions on its scope. Next, empirical work on the affordance concept is reviewed in brief and the relevance of dynamical systems theory to affordance research is demonstrated. Finally, the striking but often neglected convergence of the ideas of Gibson and those of certain …

Chronic Stress Elevates Telomerase Activity In Rats, Annaliese K. Beery, Jue Lin, Joshua S. Biddle, Darlene D. Francis, Elizabeth H. Blackburn, Elissa S. Epel

Neuroscience: Faculty Publications

The enzyme telomerase lengthens telomeres—protective structures containing repetitive DNA sequences at chromosome ends. Telomere shortening is associated with diseases of ageing in mammals. Chronic stress has been related to shorter immune-cell telomeres, but telomerase activity under stress may be low, permitting telomere loss, or high, partially attenuating it. We developed an experimental model to examine the impacts of extended unpredictable stress on telomerase activity in male rats. Telomerase activity was 54 per cent higher in stressed rats than in controls, and associated with stress-related physiological and behavioural outcomes. This significant increase suggests a potential mechanism for resilience to stress-related replicative …

Liana Abundance, Diversity, And Distribution On Barro Colorado Island, Panama, Stefan A. Schnitzer, Scott A. Mangan, James W. Dalling, Claire Baldeck, Stephen P. Hubbell, Alicia Ledo, Helene C. Muller-Laudau, Michael F. Tobin, Salomón Aguilar, David Brassfield, Andres Hernandez, Suzanne Lao, Rolando Perez, Oldemar Valdes, Suzanne R. Yorke

Biological Sciences Faculty Research and Publications

Lianas are a key component of tropical forests; however, most surveys are too small to accurately quantify liana community composition, diversity, abundance, and spatial distribution – critical components for measuring the contribution of lianas to forest processes. In 2007, we tagged, mapped, measured the diameter, and identified all lianas ≥1 cm rooted in a 50-ha plot on Barro Colorado Island, Panama (BCI). We calculated liana density, basal area, and species richness for both independently rooted lianas and all rooted liana stems (genets plus clones). We compared spatial aggregation patterns of liana and tree species, and among liana species that varied …