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1.
Zoological Lett ; 10(1): 5, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431697

RESUMO

Bats are important pollinators, but they are difficult to study since they are volant and nocturnal. Thus, long-term studies of nectarivorous bats are scarce, despite their potential to help assess trends in bat populations and their pollination services. We used capture rates of nectarivorous bats at chiropterophilous flowers in order to examine temporal trends in bat visitation in an area that is undergoing extensive land use change. We mist-netted at five bat-pollinated plant taxa (Durio zibethinus, Musa acuminata, Oroxylum indicum, Parkia speciosa, and Sonneratia spp.) in southern Thailand over six years between 2011 and 2021. We found that the most common bat species, Eonycteris spelaea, was the main visitor at all five plant taxa and had consistent visitation rates across all study years. In contrast, two other important pollinators, Macroglossus minimus and M. sobrinus, showed 80% declines in the number of individuals netted at mangrove apple (Sonneratia spp.) and banana (Musa acuminata) flowers, respectively. These findings suggest that E. spelaea (a large, cave-roosting species with a broad diet) is more tolerant of anthropogenic change than are Macroglossus bats (small, foliage-roosting species with specialized diets), which may in turn affect the reproductive success of plants pollinated by these species. Our study demonstrates how decade-long monitoring can reveal species-specific temporal patterns in pollinator visitation, emphasizing the need for tailored conservation plans. While the conservation status of most nectarivorous bats in the area is Least Concern, our results indicate that population studies in Southeast Asia are urgently needed for updated bat species conservation assessments.

2.
AoB Plants ; 16(2): plae001, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38352178

RESUMO

Argyreia versicolor and Argyreia mekongensis are extremely rare plant species. The former had not been seen for nearly 100 years until two individuals were found in Thailand in 2018, and only a handful of populations are known for the latter. The aims of this study were to examine the breeding systems of A. versicolor and A. mekongensis using pollination experiments and to determine their potential pollinators via floral observations. Our controlled pollination experiments uncovered the self-incompatibility of both species. Pollinator censuses indicated that females of two carpenter bee species, Xylocopa aestuans and Xylocopa latipes, were the predominant floral visitors for both Argyreia species. Our observations confirmed a harmonious match between the floral shape of both Argyreia species and the body sizes of these pollinators, ensuring effective pollen transfer and validating their role as putative pollinators. In line with the high frequency of pollinator visits observed, our controlled pollination experiments found no evidence of pollen limitation under field conditions. The findings of this study hold significance for the conservation of these endangered species, yet the situation is dire for A. versicolor, with one of the two individuals under study recently lost. Hence, it is crucial to intensify monitoring efforts for the species, aiming to identify additional individuals for potential inclusion in an ex-situ conservation program. Simultaneously, safeguarding the habitat of these plant species and their pollinators will be critical.

3.
BMC Plant Biol ; 23(1): 432, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715144

RESUMO

BACKGROUND: The Convolvulaceae is a large family containing species exhibiting a range of breeding systems and pollinated by diverse animal taxa. We studied the pollination ecology of 15 Convolvulaceae species, representing seven genera (Argyreia Lour., Camonea Raf., Evolvulus L., Hewittia Wight & Arn., Ipomoea L., Merremia Dennst. ex Endl., and Operculina Silva Manso), in northeastern Thailand, a family that is highly diverse yet understudied in the paleotropics. Specifically, we studied their compatibility systems and degrees of pollinator dependency using pollination experiments, examined pollinator composition and visitation rates using video observation, and determined if there is an association between pollinator visitation rates and degree of pollinator dependence. RESULTS: Our results showed that most species are self-compatible, but the degree of pollinator dependence varies. Six species were found to be highly dependent on pollinators, as two are self-incompatible and four are self-compatible but had reduced seed set when pollinators were excluded, possibly due to herkogamy. Seven species showed low dependence on pollinators and seed set remained high when pollinators were excluded. Pollinator dependence was inconclusive for two species as seed set was low in all pollination treatments. We also found an association between pollinator visitation rates and degree of pollinator dependence. Specifically, species exhibiting high pollinator dependence received frequent visits from pollinators, while species exhibiting low pollinator dependence either received frequent visits from pollinators (and received high amounts of xenogamous pollen) or infrequent visits from pollinators (and received significantly lower amounts of xenogamous pollen). Most of our study species were primarily visited by bees (e.g., Lasioglossum, Amegilla, Apis, and meliponines), with the exception of one night-blooming species that was visited primarily by crepuscular butterflies and hawkmoths. CONCLUSIONS: The cumulative findings of this study demonstrate how pollinator dependence is influenced by breeding system, and suggest that pollinator visitation is consistently high for species exhibiting high pollinator dependence but varies across species exhibiting low pollinator dependence. Our findings are also important for assessing the conservation risks of paleotropical Convolvulaceae.


Assuntos
Borboletas , Convolvulaceae , Ipomoea , Animais , Abelhas , Melhoramento Vegetal , Ecologia
4.
Inflamm Bowel Dis ; 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37650888

RESUMO

BACKGROUND: Given the complexity of inflammatory bowel disease (IBD) care, utilization of multidisciplinary teams is recommended to optimize outcomes. There is a growing recognition that clinical pharmacists should be an integral part of this care model. We sought to define the roles of IBD clinical pharmacists in the United States. METHODS: A national multidisciplinary expert panel of 12 gastroenterologists and clinical pharmacists practicing in IBD clinics was assembled. We used the RAND/University of California, Los Angeles appropriateness method, with a total of 281 statements generated based on a systematic literature review and expert opinion. Each statement was anonymously rated as appropriate, uncertain, or inappropriate in 2 rounds of voting. RESULTS: The number of publications evaluating the clinical pharmacists' roles in IBD is limited, primarily focusing on thiopurine initiation and monitoring, medication adherence, and switching to biosimilars. Medication education; medication initiation and monitoring; therapeutic drug monitoring; biosimilar management; health maintenance review; and transitions of care were deemed by the panel to be appropriate roles for IBD clinical pharmacists. In considering real-world settings, IBD clinical pharmacists should practice clinically under a predefined scope and primarily focus on complex treatments (eg, immunomodulators, biologics, and small molecules). Clinical pharmacists should also be included in practice settings with IBD specialized physicians. Additionally, clinical pharmacists caring for patients with IBD should be residency trained and board certified. CONCLUSIONS: This consensus defines IBD clinical pharmacists' roles and provides a framework for embedded clinical pharmacists in IBD care.

5.
Animals (Basel) ; 12(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36230422

RESUMO

Forest management practice plays a critical role in conserving biodiversity. However, there are few studies on how forest management practice affects bird communities. Here, we compare the effectiveness of the Panchase Protection Forest (PPF; protected forest with government administration) and the Tibrekot Community Forest (TCF; community forest with community forest users' group administration) in hosting bird diversity in the mid-hills of Nepal. We examined 96 point count stations during summer and winter in 2019 and recorded 160 species of birds with three globally threatened vultures (red-headed vulture Sarcogyps calvus, slender-billed vulture Gyps tenuirostris, and white-rumped vulture Gyps bengalensis). Forest management practice, season, and elevation all influenced the richness and abundance of birds. The diversity, richness, and abundance of birds and the most common feeding guilds (insectivore, omnivore, and carnivore) were higher in TCF than in PPF; however, globally threatened species were only recorded in PPF. We also recorded a higher bird species turnover (beta diversity) in TCF than in PPF. Our study indicates that community-managed forests can also provide quality habitats similar to those of protected forests managed by the government, and provide refuge to various bird species and guilds. However, we recommend more comparative studies in other tropical and sub-tropical areas to understand how different forest management practices influence bird diversity.

6.
J Fungi (Basel) ; 8(8)2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-36012811

RESUMO

Periglandula is a fungal genus that is associated with plants in the family Convolvulaceae. They produce medicinally important constituents called ergot alkaloids, which are stored in their host plants. Previously, the fungi were reported to mainly interact with young leaves and seeds of Convolvulaceae species. However, knowledge about how ergot alkaloid-producing fungi interact with their host plants is still lacking. Therefore, we investigated the interaction of Periglandula fungus with different plant parts of Ipomoea asarifolia, using molecular, histochemical, anatomical and micromorphological techniques. Our findings confirm the presence of Periglandula ipomoeae on six out of the eight plant parts examined (young folded leaves, mature leaves, flower buds, mature flowers, young seeds and mature seeds). The fungus was mostly distributed along external plant surfaces, and particularly on areas that were relatively unexposed. Our results suggest that the density of fungal mycelium varies depending on glandular trichome density and the growth stage of the host plant. Detection of the fungus in the flowers of its host plant, for the first time, fills a missing link in understanding how vertical transmission of Periglandula species occurs.

7.
Plants (Basel) ; 11(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35956546

RESUMO

Plants have evolved numerous secretory structures that fulfill diverse roles and shape their interactions with other organisms. Rivea ornata (Roxb.) Choisy (Convolvulaceae) is one species that possesses various external secretory organs hypothesized to be ecologically important. This study, therefore, aimed to investigate five secretory structures (nectary disc, petiolar nectaries, calycinal glands, staminal hairs, and foliar glands) using micromorphology, anatomy, histochemistry, and field observations of plant-animal interactions in order to assess the functional contributions of these structures. Results show that the nectary disc and petiolar nectaries are complex working units consisting of at least epidermis and ground tissue, while the other structures are glandular trichomes. Various groups of metabolites (lipids, phenolic compounds, polysaccharides, terpenoids, flavonoids, and alkaloids) were detected in all structures, while starch grains were only found in the nectary disc, petiolar nectaries, and their adjacent tissues. Integrating preliminary observation of animal visitors with micromorphological, anatomical, and histochemical results, two hypotheses are proposed: (I) nectary disc and staminal hairs are important for pollination as they potentially attract and reward floral visitors, and (II) petiolar nectaries, calycinal glands, and foliar glands contribute to plant defense. Specifically, petiolar nectaries and calycinal glands provide protection from herbivores via guard ants, while calycinal and foliar glands may use plant metabolites to help prevent tissue damage from dehydration and insolation.

8.
New Phytol ; 235(4): 1629-1640, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35194792

RESUMO

The evolution of floral traits is often considered to reflect selection for increased pollination efficiency. Known as the pollination-precision hypothesis, increased pollination efficiency is achieved by enhancing pollen deposition on precise areas of the pollinator. Most research to date addressing this hypothesis has examined plant species that are a priori predicted to place pollen precisely, but we still lack comparisons with species predicted to have low pollination efficiency. We studied 39 plant species with diverse floral morphologies and measured the precision of pollen placement on two pollinator groups: honey bees (genus Apis) and nectar bats (family Pteropodidae). Pollen was collected from four locations of each pollinator's body (bees: dorsal thorax, ventral thorax, dorsal abdomen, ventral abdomen; bats: crown, face, chest, wing) to calculate pollen placement precision using Pielou's evenness index. We also quantified variation in floral design by scoring floral symmetry, corolla fusion, floral orientation and stamen number. We confirm the importance of four floral character states (bilateral symmetry, fused corollas, horizontal orientation and reduced stamen number) in promoting precise pollen placement on diverse pollinators. Our findings provide phylogenetically corrected, empirical support that the evolution of the four floral characters reflect selection for enhanced precision of pollen placed on pollinators.


Assuntos
Quirópteros , Polinização , Animais , Abelhas , Flores , Néctar de Plantas , Pólen
9.
Ann Pharmacother ; 56(5): 592-599, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34423657

RESUMO

OBJECTIVE: To review the pharmacological and clinical profile of ozanimod in the treatment of ulcerative colitis (UC). DATA SOURCES: A PubMed search was conducted from inception to July 2021 using the keywords ozanimod, ulcerative colitis, and sphingosine 1-phosphate receptor modulator. Information was also extracted from published abstracts and the package insert. STUDY SELECTION AND DATA EXTRACTION: Phase 2 and 3 studies and relevant literature on ozanimod pharmacological and clinical profiles were reviewed. DATA SYNTHESIS: Ozanimod approval was based on True North, a phase 3 trial evaluating ozanimod's efficacy and safety in the treatment of moderate to severe UC. Compared with placebo, ozanimod led to clinical remission in a significantly higher proportion of patients in both the induction and maintenance phase. Additionally, for secondary end points of clinical response, endoscopic improvement, corticosteroid-free remission, and mucosal healing, ozanimod performed significantly better than placebo. Common adverse events included infections, headaches, hypertension, bradycardia, and liver enzyme elevations. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: Ozanimod is the first sphingosine 1-phosphate modulator to be approved for UC and is administered orally. Its efficacy profile is comparable with other UC medications. However, its safety profile is unique, requiring extensive assessments prior to initiation of and during treatment. Thus, it is unclear how ozanimod will be positioned in UC treatment. CONCLUSION: Ozanimod is another option in the growing arsenal of UC treatment. Although it offers a novel mechanism of action and is administered orally, there are important safety, dosing, and pharmacokinetic factors to consider prior to initiation and use.


Assuntos
Colite Ulcerativa , Indanos , Oxidiazóis , Ensaios Clínicos Fase III como Assunto , Colite Ulcerativa/tratamento farmacológico , Humanos , Fatores Imunológicos , Indanos/efeitos adversos , Oxidiazóis/efeitos adversos , Moduladores do Receptor de Esfingosina 1 Fosfato/efeitos adversos
10.
Plants (Basel) ; 10(11)2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34834765

RESUMO

Argyreia siamensis is extremely rare, and very little is known about its reproduction. The species has colorful flowers that seem likely to attract pollinators, but population sizes are typically small (<30 individuals). To determine whether poor reproduction contributes to its rarity, we investigated its mating system and potential pollinators in two populations. We also examined the staminal trichomes and floral nectary to investigate their role in pollinator attraction. The mating system was assessed with a bagging experiment and pollinator visits were recorded with action cameras. Additionally, we tested the staminal trichomes and floral nectary for terpenes and flavonoids and examined floral nectary micromorphology via scanning electron microscope and compound light microscope. Our results reveal that A. siamensis is self-incompatible and dependent on pollinators; the western population was pollinated by bees (Meliponini and Amegilla), while the eastern population was mainly pollinated by skipper butterflies (Hesperiidae). Both staminal trichomes and the floral nectary appear to contribute to pollinator attraction through the presence of terpenes and flavonoids (in both secretory structures) and nectariferous tissue and nectarostomata (in the nectary). Our results indicate that A. siamensis has reliable and effective pollinators and that insufficient pollination is likely not a primary cause of its rarity.

11.
JMIR Pediatr Parent ; 4(3): e26040, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34319249

RESUMO

BACKGROUND: Virtual reality (VR) has shown promise in reducing children's pain and anxiety during venipuncture, but studies on VR lack objective observations of pediatric coping. Notably, the process of capturing objective behavioral coping data can be labor- and personnel-intensive. OBJECTIVE: The primary aims of this pilot trial were to assess the feasibility of conducting a trial of VR in a pediatric emergency department and the feasibility of documenting observed coping behaviors during pediatric procedures. Secondarily, this study examined whether VR affects child and caregiver coping and distress during venipuncture in the pediatric emergency department. METHODS: This stratified, randomized, controlled pilot trial compared coping and distress between child life-supported VR engagement and child life specialist support without VR during painful procedures in children aged 7-22 years in the pediatric emergency department. An external control (reference group) received no standardized support. Primary feasibility outcomes included rates of recruitment, rates of withdrawal from VR, and rates of completed Child Adult Medical Procedure Interaction Scale-Short Form (CAMPIS-SF) observations. Secondary clinical outcomes were applied to venipuncture procedures and included CAMPIS-SF coping and distress (range 0-1.0), pain and anxiety on a visual analog scale (range 0-10), and cybersickness symptoms. RESULTS: Overall recruitment was 93% (66/71), VR withdrawal rate was 27% (4/15), and of the completed procedures, 100% (63/63) CAMPIS-SF observations were completed. A total of 55 patients undergoing venipuncture in the pediatric emergency department were included in the analyses of clinical outcomes: 15 patients (15 caregivers) randomized to VR, 20 patients (15 caregivers) randomized to child life specialist support, and 20 patients (17 caregivers) in the reference group. Patient coping differed across groups with higher coping in the VR group and child life specialist group than in the reference group (P=.046). There were no significant differences in the distress and pain ratings for patients and caregivers between the groups. Caregivers rated the lowest perceived anxiety in the child life specialist group (P=.03). There was no apparent change in cybersickness symptoms before and after VR use (P=.37). CONCLUSIONS: Real-time documentation of observed behaviors in patients and caregivers was feasible during medical procedures in which VR was utilized, particularly with the availability of research staff. VR and child life specialists improved coping in children during venipuncture procedures. Given the high participation rate, future studies to evaluate the efficacy of VR are recommended to determine whether an off-the-shelf VR headset can be a low-cost and low-risk tool to improve children's coping during venipuncture or other related procedures. TRIAL REGISTRATION: ClinicalTrials.gov NCT03686176; https://clinicaltrials.gov/ct2/show/NCT03686176.

12.
Hosp Pediatr ; 11(7): 775-778, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34127486

RESUMO

OBJECTIVES: Virtual reality (VR) therapy is growing in use and popularity during pediatric medical procedures. Currently, data that describe the hospital resources used during pediatric procedures with off-the-shelf VR games that are not tailored to medical procedures are lacking. In this study, we aimed to characterize procedural resources associated with VR use during venipuncture in a pediatric emergency department. METHODS: This was a secondary analysis of a 2-arm randomized, controlled pilot trial with an external group. Resource use was evaluated in 3 groups: child life (CL)-supported VR engagement, CL support without VR, and a reference group that received no intervention (ie, no CL and no VR). RESULTS: The study sample (N = 55) included the following: 15 patients randomly assigned to VR, 20 patients randomly assigned to CL, and 20 patients in the reference group. There was a significant difference in procedure duration, with the VR group exhibiting the longest duration compared with the CL and reference groups (P = .01). CONCLUSIONS: Longer procedure times associated with VR use during venipunctures (4-6 minutes on average) may be attributed to pauses to troubleshoot VR games not tailored for medical procedures. Although they are inexpensive and accessible, nontailored VR games may warrant the need for dedicated staff to provide restraint and/or assistance to navigate the VR application. In this study, we offer a protocol on the application of nontailored VR games for pediatric procedures. For those considering a VR program in an inpatient setting, the benefits of pain/anxiety reduction must be weighed against the resources needed, including device costs, staff availability, and increased procedure duration.


Assuntos
Realidade Virtual , Criança , Humanos , Manejo da Dor , Medição da Dor , Flebotomia , Projetos Piloto
13.
Ecol Evol ; 11(5): 2086-2099, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33717444

RESUMO

Floral attributes often influence the foraging choices of nectar-feeding butterflies, given the close association between plants and these butterfly pollinators. The diversity of butterflies is known to a large extent in Nepal, but little information is available on the feeding habits of butterflies. This study was conducted along the periphery of Rupa Wetland from January to December 2019 to assess butterfly species diversity and to identify the factors influencing their foraging choices. In total, we recorded 1535 individuals of 138 species representing all six families. For our examination of butterfly-nectar plant interactions, we recorded a total of 298 individuals belonging to 31 species of butterfly visiting a total of 28 nectar plant species. Overall, total butterfly visitation was found to be significantly influenced by plant category (herbaceous preferred over woody), floral color (yellow white and purple preferred over pink), and corolla type (tubular preferred over nontubular). Moreover, there was a significant positive correlation between the proboscis length of butterflies and the corolla tube length of flowers. Examining each butterfly family separately revealed that, for four of the families (Lycaenidae, Nymphalidae, Papilionidae, and Pieridae), none of the tested factors (flower color, plant category, and corolla type) were shown to significantly influence butterfly abundance at flowers. However, Hesperidae abundance was found to be significantly influenced by both flower color (with more butterflies observed at yellow flowers than purple) and flower type (with more butterflies observed at tubular flowers than nontubular flowers). Our results reveal that Rupa Lake is a suitable habitat for butterflies, providing valuable floral resources. Hence, further detailed studies encompassing all seasons, a greater variety of plants, and other influential factors in different ecological regions are fundamental for creating favorable environments to sustain important butterfly pollinators and help create balanced wetland ecosystems.

14.
Int J Phytoremediation ; 23(2): 162-170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32755387

RESUMO

Phenotypic plasticity is one mechanism that allows organisms to adapt to changing environmental conditions, and is especially important for plants since they are generally immobile. Recent anthropogenic disturbances such as oil spills have expanded the types of stressors that plants must cope with, and more work is needed to understand the extent to which plants can adapt. This study examined the physiological and anatomical responses of Ipomoea pes-caprae to crude oil, and determined its plasticity in response to crude oil. Four concentrations of crude oil (1%, 2%, 3%, and 4% v/w) were applied to experimental plants and then compared with control plants over the next 120 days. Crude oil meaningfully impacted 4 out of 5 physiological characters (survival time, leaf length, leaf width, and chlorophyll content) and 4 out of 19 anatomical characters (leaf blade thickness, leaf spongy layer height, leaf adaxial cutin thickness, and leaf abaxial cutin thickness). These results demonstrate that I. pes-caprae exhibits low anatomical plasticity in response to crude oil, resulting in reduced survival and physiological performance. Our findings highlight the importance of understanding how anthropogenic actions affect relatively immobile plants, which are not always able to cope with such stressors.


Assuntos
Poluição por Petróleo , Petróleo , Biodegradação Ambiental , Clorofila , Folhas de Planta
15.
J Am Pharm Assoc (2003) ; 60(5): 750-756, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32482500

RESUMO

OBJECTIVE: To create a novel screening tool that identified patients who were most likely to benefit from pharmacist in-home medication reviews. DESIGN: Single-center, retrospective study. SETTING AND PARTICIPANTS: A total of 25 homebound patients in Forsyth County, NC, aged 60 years or older with physical or cognitive impairments and enrolled in home-based primary care or transitional and supportive care programs participated in the study. Pharmacy resident-provider pairs conducted home visits for all patients in the study. Pharmacy residents assessed the subjective risk (high, medium, low) of medication nonadherence using information obtained from home visits (health literacy, support network, medications, and detection of something unexpected related to medications). An electronic medical record-based risk score was simultaneously calculated using screening tool components (i.e., electronic frailty index score, LACE+ index [length of stay in the hospital, acuity of admission, comorbidity, emergency department utilization in the 6 months before admission], and 2015 American Geriatric Society Beers Criteria). OUTCOME MEASURES: The electronic medical record-based screening tool numerical risk scores were compared with pharmacy resident subjective risk assessments using tree-based classification models to determine screening tool components that best predicted pharmacy residents' subjective assessment of patients' likelihood of benefit from in-home pharmacist medication review. Following the study, satisfaction surveys were given to providers and pharmacy residents. RESULTS: The best predictor of high-risk patients was an electronic frailty index score greater than 0.32 (indicating very frail) or LACE+ index greater than or equal to 59 (at high risk for hospital readmission). Pharmacy residents and providers agreed that homebound patients at high-risk for medication noncompliance benefited from pharmacist time and attention in home visits. CONCLUSION: In homebound older persons, this screening tool allowed for the identification of patients at high-risk for medication nonadherence through targeted in-home pharmacist medication reviews. Further studies are needed to validate the accuracy of this tool internally and externally.


Assuntos
Serviços de Assistência Domiciliar , Assistência Farmacêutica , Idoso , Idoso de 80 Anos ou mais , Humanos , Farmacêuticos , Atenção Primária à Saúde , Estudos Retrospectivos
16.
PLoS One ; 15(4): e0230490, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32275717

RESUMO

Plant-pollinator interactions are known to vary across time, both in terms of species composition and the associations between partner species. However, less is known about tropical pollination networks, and tropical urban parks provide a unique opportunity to study network stability in an environment where temperature and floral resources are relatively constant due to both the tropical climate as well as park horticulture. The objectives of this study were thus to examine the interactions between flowering plants and their potential pollinators in a large, tropical city (Bangkok, Thailand) across 12 consecutive months, and to assess the stability of network properties over time. We conducted monthly pollinator observations at 9 parks spaced throughout the city, and collected data on temperature, precipitation, floral abundance and floral species richness. We found that neither pollinator abundance nor richness varied significantly across months when all parks were pooled. However, pollinator abundance was significantly influenced by floral abundance, floral richness, and their interaction, and pollinator richness was significantly influenced by floral richness and precipitation. Finally, we found that network properties did not change across months, even as species composition did. We conclude that the year-round constancy of floral resources and climate conditions appear to create a network in dynamic equilibrium, where plant and pollinator species compositions change, but network properties remain stable. The results of this study provide useful information about how tropical pollinators respond to urban environments, which is particularly relevant given that most urban development is predicted to occur in the tropics.


Assuntos
Biodiversidade , Insetos , Parques Recreativos , Polinização , Animais , Dípteros , Ecossistema , Himenópteros , Insetos/classificação , Lepidópteros , Magnoliopsida , Plantas , Estações do Ano , Tailândia , Clima Tropical
17.
Environ Sci Pollut Res Int ; 25(28): 28075-28085, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30069774

RESUMO

Oil pollution is one potential consequence of industry development, and oil contamination occurs in countries around the world. However, few studies have examined the detrimental effects of oil on plant anatomy. Therefore, the objectives of this study were (1) to determine the impacts of crude oil on the physiological and anatomical parameters of Ischaemum muticum L. (Poaceae) and (2) to examine its potential as a bioindicator of oil pollution. Experimental plants were treated with one of four concentrations of crude oil (1%, 2%, 3%, and 4% volume/weight) and compared to control plants (no oil applied). Four physiological and 23 anatomical parameters were measured 7, 15, 30, 45, and 60 days after treatment. Crude oil negatively affected both physiological traits (leaf width and chlorophyll content) and anatomical traits (midrib vascular bundle height, leaf cutin thickness, leaf vascular bundle width and height, abaxial and adaxial margin cutin thickness, adaxial stomata density, adaxial short cell width, and abaxial long cell width). In general, the affected traits were modified by even the lowest oil concentration tested (1%). We discuss the potential of I. muticum as a bioindicator of oil pollution, given its prevalence in coastal areas of the paleotropics and its sensitivity to oil contamination.


Assuntos
Poluição por Petróleo/efeitos adversos , Petróleo/toxicidade , Poaceae/efeitos dos fármacos , Clorofila/metabolismo , Monitoramento Ambiental/métodos , Folhas de Planta/anatomia & histologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Poaceae/anatomia & histologia , Poaceae/metabolismo
18.
PeerJ ; 6: e5335, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30042902

RESUMO

BACKGROUND: Pollinators are well known for the ecosystem services they provide, and while urban areas are generally perceived as low-quality habitat for most wildlife, these cities often support a surprising degree of pollinator diversity. The current rapid growth of urban areas and concern over global pollinator declines have spurred numerous studies examining pollinator communities in temperate cities, but knowledge about tropical urban pollinators remains scarce. METHODS: This study investigated the effects of habitat and landscape factors on pollinator richness and abundance in a highly-populated, tropical city: Bangkok, Thailand. We conducted pollinator observations in 52 green areas throughout the city and collected data on patch size, floral abundance, plant richness, location type, and percent vegetation at five spatial scales. RESULTS: Of the 18,793 pollinators observed, over 98% were bees. Both patch size and floral abundance generally had positive effects on pollinators, although there was a significant interaction between the two factors; these findings were generally consistent across all focal taxa (Tetragonula stingless bees, Apis honey bees, Xylocopa carpenter bees, and butterflies). DISCUSSION: Our results demonstrate the importance of maintaining large green areas in cities, since small green areas supported few pollinators, even when floral resources were abundant. Moreover, most pollinator taxa utilized a variety of location types (e.g., public parks, school campuses, temple grounds), with the exception of butterflies, which preferred parks. Our findings are generally consistent with those of temperate urban studies, but additional studies in the tropics are needed before global patterns can be assessed.

19.
Ann Bot ; 119(1): 73-79, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27864223

RESUMO

BACKGROUND AND AIMS: Sympatric plant species that share pollinators potentially compete for pollination and risk interspecific pollen transfer, but this competition can be minimized when plant species place pollen on different areas of the pollinator's body. Multiple studies have demonstrated strong differential pollen placement by sympatric plant species under laboratory conditions; however, field evidence collected in natural settings is less common. Furthermore, it is unknown whether precise pollen placement on the pollinator's body remains constant throughout the foraging period, or if such patterns become diffused over time (e.g. due to grooming). To test the prevalence of differential pollen placement in the wild, we examined a community of five night-blooming plant species in southern Thailand that share common bat pollinators. METHODS: We mist-netted wild foraging nectar bats and collected pollen samples from four body parts: the crown of the head, face, chest and ventral side of one wing. We also noted the time of pollen collection to assess how pollinator pollen loads change throughout the foraging period. KEY RESULTS: Our findings revealed that most of our plant study species placed pollen on precise areas of the bat, consistent with experimental work, and that patterns of differential pollen placement remained constant throughout the night. CONCLUSIONS: This study demonstrates how diverse floral morphologies effectively limit interspecific pollen transfer among Old World bat-pollinated plants under natural conditions. Additionally, interspecific pollen transfer is probably minimal throughout the entire foraging period, since patterns of pollen on the bats' bodies were consistent over time.


Assuntos
Quirópteros , Flores/anatomia & histologia , Pólen/anatomia & histologia , Polinização , Animais , Flores/fisiologia , Polinização/fisiologia , Tailândia
20.
Ann Bot ; 117(1): 145-52, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26482654

RESUMO

BACKGROUND AND AIMS: Plant species that share pollinators are potentially subject to non-adaptive interspecific pollen transfer, resulting in reduced reproductive success. Mechanisms that increase pollination efficiency between conspecific individuals are therefore highly beneficial. Many nocturnally flowering plant species in Thailand are pollinated by the nectar bat Eonycteris spelaea (Pteropodidae). This study tested the hypothesis that plant species within a community reduce interspecific pollen movement by placing pollen on different areas of the bat's body. METHODS: Using flight cage trials, pollen transfer by E. spelaea was compared between conspecific versus heterospecific flowers across four bat-pollinated plant genera. Pollen from four locations on the bat's body was also quantified to determine if pollen placement varies by plant species. KEY RESULTS: It was found that E. spelaea transfers significantly more pollen between conspecific than heterospecific flowers, and that diverse floral designs produce significantly different patterns of pollen deposition on E. spelaea. CONCLUSIONS: In the Old World tropics, differential pollen placement is a mechanism that reduces competition among bat-pollinated plant species sharing a common pollinator.


Assuntos
Quirópteros/fisiologia , Néctar de Plantas/fisiologia , Pólen/fisiologia , Polinização/fisiologia , Animais , Intervalos de Confiança , Flores/anatomia & histologia , Modelos Biológicos
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