{"title":"Effect of expanding clones of Gaylussacia baccata (black huckleberry) on species composition in sandplain grassland on Nantucket Island, Massachusetts","authors":"K. Harper, K. Koch","doi":"10.2307/2996451","DOIUrl":"https://doi.org/10.2307/2996451","url":null,"abstract":"community were investigated. Expansion rates of G. baccata clones were determined by measuring the diameters of clones on 1975 aerial photographs and in the field in 1990. Data were collected on the cover, maximum height and stem density of G. baccata, as well as the presence of other species, in 0.25 m2 quadrats placed along radial transects within and outside clones. G. baccata clones nearly doubled in area from 1975 to 1990. Clone expansion was accompanied by an increase in G. baccata cover, height and stem density, and a corresponding decrease in species richness. The frequencies of other plant species displayed three different patterns along a transect into G. baccata clones: no change, a gradual decrease, and a sharp decrease in frequency at the clone edge.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996451","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68407108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fifteen-Year Population and Habitat Changes in a Narrow Idaho Endemic, Phlox idahonis Wherry","authors":"R. Moseley, Rex C. Crawford","doi":"10.2307/2996449","DOIUrl":"https://doi.org/10.2307/2996449","url":null,"abstract":"","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996449","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68407514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tropical Forests: Management and Ecology","authors":"A. Lugo, C. Lowe","doi":"10.1007/978-1-4612-2498-3","DOIUrl":"https://doi.org/10.1007/978-1-4612-2498-3","url":null,"abstract":"","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/978-1-4612-2498-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50952475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Photosynthesis and water-use efficiency of two sandhill oaks following additions of water and nutrients","authors":"M. Vaitkus, K. McLeod","doi":"10.2307/2996401","DOIUrl":"https://doi.org/10.2307/2996401","url":null,"abstract":"VAITKUS, M. R. AND K. W. McLEOD (Savannah River Ecology Laboratory, P.O. Drawer E, Aiken, SC 29802). Photosynthesis and water-use efficiency of two sandhill oaks following additions of water and nutrients. Bull. Torrey Bot. Club 122: 30-39. 1995.-Water and nutrients are considered the primary factors limiting vegetative growth in many plant communities. We examined the effects of added water and nutrients on photosynthesis and water use efficiency (WUE) of juveniles of Quercus hemisphaerica and Quercus laevis growing together in a sandhill community in South Carolina. Supplemental water and nutrients were added in a 2 x 2 factorial design. Diurnal photosynthesis was determined approximately biweekly from June to October and integrated long-term WUE was evaluated using carbon isotope discrimination at the end of this period. Analysis of diurnal photosynthesis curves indicated no significant differences between species, but differences within species were significant between day of sampling, time of measurement, and treatment. Net photosynthesis of Q. hemisphaerica in watered treatments was significantly greater than photosynthesis in unwatered treatments, primarily at midday on days with high temperatures following prolonged drought. Neither nutrients nor water significantly affected the photosynthesis of Q. laevis, regardless of environmental conditions. Fertilization was found to differentially affect WUE of Q. hemisphaerica and Q. laevis, possibly confounding WUE differences between these two species. Because Q. hemisphaerica is often found in more mesic environments than Q. laevis, and because it responded to the addition of water with an increase in photosynthesis, we concluded that in a sandhill community Q. hemisphaerica juveniles are limited primarily by water rather than by low fertility. Our results indicated that juveniles of Q. laevis, the community dominant, are not as plastic as Q. hemisphaerica in their response to fertilizer and water additions.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996401","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68406683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Greller, L. McDade, K. Bawa, H. Hespenheide, G. Hartshorn
{"title":"La Selva: ecology and natural history of a neotropical rain forest.","authors":"A. Greller, L. McDade, K. Bawa, H. Hespenheide, G. Hartshorn","doi":"10.2307/2996404","DOIUrl":"https://doi.org/10.2307/2996404","url":null,"abstract":"La Selva, a nature reserve and field station in Costa Rica, is one of the most intensively studied and best-understood tropical field sites in the world. For over 30 years, La Selva has been a major focus of research on rainforest ecology, flora and fauna. This volume provides a comprehensive review of this research, covering La Selva's geographical history and physical setting, its plant and animal life, and agricultural development and land use. Drawing together a wealth of information, \"La Selva\" offers a substantive treatment of the ecology of a rainforest. Part 1 summarizes research on the physical setting and environment of the rainforest, as well as the history of the research station. Some chapters in this part focus on climate, geomorphology and aquatic systems, while others look at soils, nutrient acquisition and cycles of energy. Part 2 synthesizes what is known about the plant community. It begins with chapters on vegetation types and plant diversity, and also explores plant demography, spatial patterns of trees, and the impact of treefall gaps on forest structure and dynamics. Other chapters address plant physiological ecology, as well as plant reproductive systems. Part 3 covers the animal community, summarizing information on the six best-known animal taxa of the region: fishes, amphibians, reptiles, birds, mammals and butterflies. This part includes an overview of faunal studies at La Selva and a chapter on animal population biology, which examines animal demography and abundance, and interactions between predators and prey. Part 4 addresses interactions between plants and animals and the effects of these interactions on species diversity. Part 5 considers the impact of land use and agricultural development on La Selva and other areas of Costa Rica. One chapter examines land colonization and conservation in Sarapiqui, another covers subsistence and commercial agricultural development in the Atlantic lowlands region, and a third looks at the forest industry in north-eastern Costa Rica. This part also assesses the role and research priorities of La Selva. \"La Selva\" provides an introduction to tropical ecology for students and researchers at La Selva, a major source of comparative information for biologists working in other tropical areas, and a resource for conservationists.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996404","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68406803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The reproductive biology of Vincetoxicum nigrum (L.) Moench (Asclepiadaceae), a Mediterranean weed in New York State.","authors":"Cecile Lumer, Susan E. Yost","doi":"10.2307/2996399","DOIUrl":"https://doi.org/10.2307/2996399","url":null,"abstract":"York. The small, dark purple flowers open in the morning and remain open for approximately 7 days. Although a heavy, fruity, unpleasant scent is emitted throughout the day and night, it is strongest during the day. The first flowers appear in mid-May, but peak flowering occurs in mid- to late-June, tapering off in early July. The flowers are autogamous, with 4.2% of 167 bagged flowers setting fruits with viable seeds, as compared to 1 1. 1% of 72 unbagged flowers. In addition, the plants are clonal, with deep roots and rhizomes. Of 50 seeds tested in September (without a period of dormancy) 14 germinated, versus 20 of 50 that had overwintered. Of seeds from unbagged flowers, 49% germinated versus 40% of those produced by autogamy. Although more than 14 species of flies visited the flowers of V. nigrum, only six species, representing four families, carried V. nigrum pollinia. Flies pick up pollinia on their proboscises as they probe for nectar. A large territorial fly, Sarcophaga sp., defends flowers from visits by other flies.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996399","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68406620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Variation in survival and biomass of two wetland grasses at different nutrient and water levels over a six week period1","authors":"C. Figiel, B. Collins, G. Wein","doi":"10.2307/2996400","DOIUrl":"https://doi.org/10.2307/2996400","url":null,"abstract":"was greatest in moist and emergent water levels. Both species produced greater biomass in the high nutrient treatment than in the low nutrient treatment. Root: shoot biomass ratio increased for both species with decreasing nutrient level; however, the root: shoot ratio of Echinochloa was significantly lower than that of Phalaris at both nutrient levels. Interspecific competition did not adversely affect survival or biomass allocation strategy of either species; rather, their greater survival in mixture than in monoculture suggests that intraspecific competition is relatively more important for both. In wetlands, Phalaris may be more successful than Echinochloa in fluctuating and submerged water because of low Echinochloa survival.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996400","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68406642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparative Gradient Structure and Forest Cover Types in Lassen Volcanic and Yosemite National Parks, California","authors":"A. J. Parker","doi":"10.2307/2996403","DOIUrl":"https://doi.org/10.2307/2996403","url":null,"abstract":"","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996403","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68406743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Habitat distribution and competitive neighborhoods of two Florida palmettos","authors":"W. Abrahamson","doi":"10.2307/2996398","DOIUrl":"https://doi.org/10.2307/2996398","url":null,"abstract":"ABRAHAMSON, W. G. (Department of Biology, Bucknell University, Lewisburg, PA 17837). Habitat distribution and competitive neighborhoods of two Florida palmettos. Bull. Torrey Bot. Club 122: 1-14.-Two ecologically similar palmettos, Serenoa repens and Sabal etonia, co-occur on the Florida peninsula's central and Atlantic coast ridges. Inasmuch as they share many characteristics of growth form, reproductive strategies, responses to fire, and habitat occurrence, these palmettos may be able to coexist because they occur in different microhabitats or plant neighborhoods. Serenoa reached its highest dominance in poorly drained flatwoods and its lowest dominance in well-drained sandhills. Sabal, on the other hand, was uncommon in flatwoods but exhibited its highest dominance in well-drained sand pine scrub and sandhills. Nearest-neighbor and principal components analyses showed that Sabal neighborhoods potentially had more competitive interference and in flatwoods included more oak (Quercus geminata) and fetterbush (Lyonia lucida) than Serenoa neighborhoods. These differences in species microsite-distribution patterns suggest spatial displacement of palmettos based at least partially on competitive interference and adaptations to edaphic conditions. Local populations had different growth forms such that palmettos growing in flatwoods communities lived in more closely spaced but lower canopied neighborhoods and bore more leaves than palmettos growing in scrubby flatwoods. Palmetto leaf numbers of both species were higher in recently burned sites but Serenoa maintained more leaves than Sabal under all post-bum conditions. Measures of plant vigor and performance (e.g., crown size, biomass) did not exhibit the trends expected based on palmetto abundance patterns; rather, local effects (e.g., overstory canopy coverage) may more strongly affect performance. Seedling and adult palmettos had very low mortality rates and slow growth rates suggesting that extremely long-lived individuals (500 yr old palmettos may not be uncommon) compose populations that have remarkably low turnover of genotypes-a likely consequence of adaptation to long-lived, stable environments. These palmettos are vulnerable to human-caused disturbance because of their limited ability to quickly recolonize former habitats.","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996398","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68407069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Collapsible water-storage cells in cacti","authors":"J. Mauseth","doi":"10.2307/2996453","DOIUrl":"https://doi.org/10.2307/2996453","url":null,"abstract":"MAUSETH, J. D. (Department of Botany, University of Texas, Austin, TX 78713). Collapsible water-storage cells in cacti. Bull. Torrey Bot. Club 122: 145-151. 1995.-Part of the cortex in several genera of cacti consists of cells that have highly undulate walls; the cells are collapsed and shrunken. The outermost, photosynthetic cortical cells and the innermost cortical cells, those immediately adjacent to the stele, are not collapsed but instead are large, turgid, isodiametric cells with smooth walls. Cortical bundles that run through the collapsible region are contorted, probably having been distorted by shrinkage of the surrounding cells. The region of collapsible parenchyma cells apparently is a specialized water-storage tissue: by having flexible walls, they lose their water most easily, thus facilitating transfer of water to other cells whose walls are more rigid. Also, they may be the last to refill when water is available, the water going first to cells with more inflexible walls. This tissue was found in Bolivicereus, Borzicactus, Cleistocactus, Espostoa, Gymnocalycium, Haageocereus, Loxanthocereus (all considered closely related), and Jasminocereus (not considered closely related to the others).","PeriodicalId":9453,"journal":{"name":"Bulletin of the Torrey Botanical Club","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/2996453","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68407181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}