189 research outputs found

    Floristic response to urbanization: Filtering of the bioregional flora in Indianapolis, Indiana, USA

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    PREMISE OF THE STUDY: Globally, urban plant populations are becoming increasingly important, as these plants play a vital role in ameliorating effects of ecosystem disturbance and climate change. Urban environments act as filters to bioregional flora, presenting survival challenges to spontaneous plants. Yet, because of the paucity of inventory data on plants in landscapes both before and after urbanization, few studies have directly investigated this effect of urbanization. METHODS: We used historical, contemporary, and regional plant species inventories for Indianapolis, Indiana USA to evaluate how urbanization filters the bioregional flora based on species diversity, functional traits, and phylogenetic community structure. KEY RESULTS: Approximately 60% of the current regional flora was represented in the Indianapolis flora, both historically and presently. Native species that survived over time were significantly different in growth form, life form, and dispersal and pollination modes than those that were extirpated. Phylogenetically, the historical flora represented a random sample of the regional flora, while the current urban flora represented a nonrandom sample. Both graminoid habit and abiotic pollination are significantly more phylogenetically conserved than expected. CONCLUSIONS: Our results likely reflect the shift from agricultural cover to built environment, coupled with the influence of human preference, in shaping the current urban flora of Indianapolis. Based on our analyses, the urban environment of Indianapolis does filter the bioregional species pool. To the extent that these filters are shared by other cities and operate similarly, we may see increasingly homogenized urban floras across regions, with concurrent loss of evolutionary information

    Chromosome Number Changes Associated with Speciation in Sedges: a Phylogenetic Study in Carex section Ovales (Cyperaceae) Using AFLP Data

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    Phylogenetic analysis of amplified fragment length polymorphisms (AFLP) was used to infer patterns of morphologic and chromosomal evolution in an eastern North American group of sedges (ENA clade I of Carex sect. Ovales). Distance analyses of AFLP data recover a tree that is topologically congruent with previous phylogenetic estimates based on nuclear ribosomal DNA (nrDNA) sequences and provide support for four species groups within ENA clade I. A maximum likelihood method designed for analysis of restriction site data is used to evaluate the strength of support for alternative topologies. While there is little support for the precise placement of the root, the likelihood of topologies in which any of the four clades identified within the ENA clade I is forced to be paraphyletic is much lower than the likelihood of the optimal tree. Chromosome counts for a sampling of species from throughout sect. Ovales are mapped onto the tree, as well as counts for all species in ENA clade I. Parsimony reconstruction of ancestral character states suggest that: (1) Heilborn’s hypothesis that more highly derived species in Carex have higher chromosome counts does not apply within sect. Ovales, (2) the migration to eastern North America involved a decrease in average chromosome count within sect. Ovales, and (3) intermediate chromosome counts are ancestral within ENA clade I. A more precise understanding of chromosomal evolution in Carex should be possible using likelihood analyses that take into account the intraspecific polymorphism and wide range of chromosome counts that characterize the genus

    Isolation of 11 Polymorphic Tri- and Tetranucleotide Microsatellite Loci in a North American Sedge (\u3ci\u3eCarex scoparia\u3c/i\u3e: Cyperaceae) and Cross-Species Amplification in Three Additional \u3ci\u3eCarex\u3c/i\u3e Species

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    We report on the isolation and evaluation of 11 microsatellites from a widespread eastern North American wetland sedge, Carex scoparia. Loci exhibit 3–9 alleles over five populations and significant FIS (0.204–0.717) in most populations. All primers cross-amplify in at least two other species, and 10 cross-amplify in the more distantly related C. stipata. These markers will be used to examine population genetics and patterns of chromosomal diversification in this ecologically important sedge species and its relatives

    Phylogeny and biogeography of Croton alabamensis (Euphorbiaceae), a rare shrub from Texas and Alabama, using DNA sequence and AFLP data

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    Croton alabamensis (Euphorbiaceae s.s. ) is a rare plant species known from several populations in Texas and Alabama that have been assigned to var. texensis and var. alabamensis , respectively. We performed maximum parsimony, maximum likelihood, and Bayesian analyses of DNA sequences from the nuclear ribosomal internal transcribed spacer (ITS) and 5.8S regions and chloroplast trn L- trn F regions from collections of the two varieties of C. alabamensis and from outgroup taxa. C. alabamensis emerges alone on a long branch that is sister to Croton section Corylocroton and the Cuban endemic genus Moacroton . Molecular clock analysis estimates the split of C. alabamensis from its closest relatives in sect. Corylocroton at 41 million years ago, whereas the split of the two varieties of C. alabamensis occurred sometime in the Quaternary. Amplified fragment length polymorphism (AFLP) analyses were performed using two selective primer pairs on a larger sampling of accessions (22 from Texas, 17 from Alabama) to further discriminate phylogenetic structure and quantify genetic diversity. Using both neighbour joining and minimum evolution, the populations from the Cahaba and Black Warrior watersheds in Alabama form two well-separated groups, and in Texas, geographically distinct populations are recovered from Fort Hood, Balcones Canyonlands, and Pace Bend Park. Most of the molecular variance is accounted for by variance within populations. Approximately equal variance is found among populations within states and between states (varieties). Genetic distance between the Texas populations is significantly less than genetic distance between the Alabama populations. Both sequence and AFLP data support the same relationships between the varieties of C. alabamensis and their outgroup, while the AFLP data provide better resolution among the different geographical regions where C. alabamensis occurs. The conservation implications of these findings are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72311/1/j.1365-294X.2006.02970.x.pd

    White-Tailed Deer are a Biotic Filter During Community Assembly, Reducing Species and Phylogenetic Diversity

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    Community assembly entails a filtering process, where species found in a local community are those that can pass through environmental (abiotic) and biotic filters and successfully compete. Previous research has demonstrated the ability of white-tailed deer (Odocoileus virginianus) to reduce species diversity and favour browse-tolerant plant communities. In this study, we expand on our previous work by investigating deer as a possible biotic filter altering local plant community assembly. We used replicated 23-year-old deer exclosures to experimentally assess the effects of deer on species diversity (H′), richness (SR), phylogenetic community structure and phylogenetic diversity in paired browsed (control) and unbrowsed (exclosed) plots. Additionally, we developed a deer-browsing susceptibility index (DBSI) to assess the vulnerability of local species to deer. Deer browsing caused a 12 % reduction in H′ and 17 % reduction in SR, consistent with previous studies. Furthermore, browsing reduced phylogenetic diversity by 63 %, causing significant phylogenetic clustering. Overall, graminoids were the least vulnerable to deer browsing based on DBSI calculations. These findings demonstrate that deer are a significant driver of plant community assembly due to their role as a selective browser, or more generally, as a biotic filter. This study highlights the importance of knowledge about the plant tree of life in assessing the effects of biotic filters on plant communities. Application of such knowledge has considerable potential to advance our understanding of plant community assembly

    Analisis Kesediaan Membayar Wtp (Willingness To Pay) dalam Upaya Pengelolaan Obyek Wisata Taman Alun Kapuas Pontianak, Kalimantan Barat

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    Berbagai fungsi yang terkait dengan sumber daya alam (fungsi ekologis, sosial, ekonomi, dan arsitektural) dannilai estetika yang dimilikinya (obyek dan lingkungan) dapat meningkatkan kualitas lingkungan dan untukkelangsungan kehidupan perkotaan juga dapat menjadi nilai kebanggaan dan identitas kota. Sebagai obyekwisata alam, Taman Alunalun Kapuas belum tertata dengan baik, pelaksanaan upaya pengelolaan objek wisataTaman Alun Kapuas membutuhkan biaya yang tidak sedikit. Untuk itu diharapkan bagi pengunjung untukmembayar dalam pengelolaan Taman Alun Kapuas. Penelitian ini menggunakan analisis regresi logistik dalammenganalisis faktor-faktor kesediaan pengunjung untuk membayar. Sedangkan metode CVM (ContingenValuation Method) digunakan untuk mengestimasi biaya yang akan dikeluarkan oleh pengunjung, dan metoderegresi berganda digunakan untuk menganalisis faktor-faktor apa yang mempengaruhi besar kesediaanmembayar pengunjung. Program yang dapat membantu dalam penelitian ini yaitu Microsoft Excel 2007 danMinitab For Windows Realise 16. Hasil penelitian menunjukkan bahwa sebanyak 84% responden bersediamembayar dalam upaya pengelolaan lingkungan obyek wisata Taman Alun Kapuas. Faktor-faktor yangmempengaruhi kesediaan membayar responden pengunjung dalam upaya pengelolaan lingkungan obyekwisata Taman Alun Kapuas antara lain pendapatan (PNDPTN3) dan pengetahuan (PNGTHUAN). Nilai rata-rataWTP responden pengunjung adalah sebesar Rp 3360,00/orang. Faktor yang mempengaruhi nilai WTPresponden yaitu usia (U)

    ParkIndex: Validation and Application of a Pragmatic Measure of Park Access and Use

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    Composite metrics integrating park availability, features, and quality for a given address or neighborhood are lacking. The purposes of this study were to describe the validation, application, and demonstration of ParkIndex in four diverse communities. This study occurred in Fall 2018 in 128 census block groups within Seattle(WA), Brooklyn(NY), Raleigh(NC), and Greenville County(SC). All parks within a half-mile buffer were audited to calculate a composite park quality score, and select households provided data about use of proximal parks via an online, map-based survey. For each household, the number of parks, total park acreage, and average park quality score within one half-mile were calculated using GIS. Logistic regression was used to identify a parsimonious model predicting park use. ParkIndex values (representing the probability of park use) were mapped for all study areas and after scenarios involving the addition and renovation/improvement of parks. Out of 360 participants, 23.3% reported visiting a park within the past 30 days. The number of parks (OR = 1.36, 95% CI = 1.15–1.62), total park acreage (OR = 1.13, 95% CI = 1.07–1.19), and average park quality score (OR = 1.04, 95% CI = 1.01–1.06) within one half-mile were all associated with park use. Composite ParkIndex values across the study areas ranged from 0 to 100. Hypothetical additions of or renovations to study area parks resulted in ParkIndex increases of 22.7% and 19.2%, respectively. ParkIndex has substantial value for park and urban planners, citizens, and researchers as a common metric to facilitate awareness, decision-making, and intervention planning related to park access, environmental justice, and community health

    Pemanfaatan Aplikasi Mind Map Sebagai Media Inovatif Dalam Pembelajaran Mata Kuliah Pengembangan Pendidikan Kewarganegaraan Sekolah Dasar

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    This study was conducted to develop an innovative medium in learning Elementary School-Civic Education (PKn SD) Development course in order to improve the lecturer competency in developing good learning media, improving learning quality, and producing a computer and internet-based media product. The development of innovative media in this study was carried out by utilizing mind map application available in internet. This study was taken place in Elementary School Teacher Education, Pedagogic Faculty, Semarang State University. The subject of research consisted of corresponding students and lecturers. This study was an educational research with research and development approach. The procedure of research included preliminary study with descriptive qualitative approach, media development design, design validation and design improvement, and followed with limited trial on media design by applying experimental method (before-after), and product revision, if any, and final product development. The result achieved in this study was that the author had conducted a preliminary study by mapping competency and indicator into PKn SD Development course and then designed the lecturing learning plan as needed by utilizing the mind map application as learning media. The author had designed an innovative media using mind map application and had the media design validated by the competent validators in their area. The mind map application-based learning media had been tried out in treatment class. The result of test with the data processed by the author showed the following result. 1) The result of pretest and posttest showed significant improvement; it could be seen from the number of correct answer minimally 5 (40%) and maximally 13 (63%) in pre-test result and minimally 16 (80%) and maximally 20 (100%) in posttest result. 2) The result of content quality and objective aspect questionnaire before and after using mind map application showed the ratio of 55%: 89%, with instructional quality aspect of 54% : 88%, and technical quality aspect of 51% : 90%, so that the overall ratio was 54% : 89%. Considering the result of data analysis, it could be found that the mind map application use can be developed further as an innovative learning media utilizing computer technology and informatics technology mastery support. The author organized the result of study into a scientific article to be published and organized a final report as accountability
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