Physical Sciences and Mathematics Commons^™

Initial Limnology Of Laguna Pozo Verde, Costa Rica: Bathymetry, Water, Sediments, And Diatoms, Sally P Horn, Erik N. Johanson, Mauricio Murillo Herrera, Kurt A. Haberyan, Taber Friedel, Chad S. Lane

Geography Publications and Other Works

ABSTRACT. Introduction: Costa Rica has hundreds of lakes, many of which have never been scientifically studied. Objective: To carry out a first, basic limnological study of Laguna Pozo Verde in Juan Castro Blanco National Park, Costa Rica (~1935m elevation), to provide baseline data for studying future changes. Methods: We measured water depths and temperatures, and Secchi depth; analyzed surface sediments; and examined maps and satellite imagery. Results: Though described by some as formed by volcanic processes, Laguna Pozo Verde likely formed in a landslide, which occur frequently in this rainy area on the steep south slope of the inactive Porvenir …

Initial Limnological Observations At Five Small Lakes In Southern Pacific Costa Rica, Sally P Horn, Erik N. Johanson, Kurt A. Haberyan, Mathew S. Boehm, Jessie L. Johanson, Maureen Sánchez P., Mario Hernández V.

Geography Publications and Other Works

Costa Rica has hundreds of lakes, many of which have never been described or sampled by limnologists. Here we summarize initial observations of five small (0.2–1.7ha) lakes located at low elevation (365–490m) in the cantón of Buenos Aries. We collected basic limnological data and samples during visits in 2013 and 2014, and compiled environmental and archaeological data for their surroundings as a contribution to the documentation of lake diversity in Costa Rica, and to support parallel investigations of indicators of environmental history preserved in the sediments of the lakes. Lagunas Carse, Los Mangos, Danta, and Ojo de Agua all appear …

Hypericum Irazuense Kuntze Ex N. Robson In The Buenavista And Chirripó Páramos Of Costa Rica: Photographs Of Stem Cross Sections, Plants, And Study Sites, Sally P Horn, Matthew T. Kerr

Geography Publications and Other Works

Hypericum irazuense Kuntze ex N. Robson is a common shrub in the high-elevation páramos that occur above treeline on the high peaks of the Cordillera de Talamanca in Costa Rica and westernmost Panama. In this report and accompanying high-resolution images we make available photographs of stem cross sections, plants, and habitats of H. irazuense in support of a recent study of the dendrochronological potential of the species (Kerr et al., forthcoming paper in Physical Geography) and other research on this plant and the páramo vegetation in which it occurs. We also include images from the Google Earth^TM map …

Fire History Of The Appalachian Region: A Review And Synthesis, Charles W. Lafon, Adam T. Naito, Henri D. Grissino-Mayer, Sally P Horn, Thomas A. Waldrop

Geography Publications and Other Works

The importance of fire in shaping Appalachian vegetation has become increasingly apparent over the last 25 years. This period has seen declines in oak (Quercus) and pine (Pinus) forests and other fire-dependent ecosystems, which in the near-exclusion of fire are being replaced by fire-sensitive mesophytic vegetation. These vegetation changes imply that Appalachian vegetation had developed under a history of burning before the fire-exclusion era, a possibility that has motivated investigations of Appalachian fire history using proxy evidence. Here we synthesize those investigations to obtain an up-to-date portrayal of Appalachian fire history. We organize the report by …

Incendios En Los Pinares De Las Zonas Montañosas De La República Dominicana: La Visión De Fondo, Sally P Horn

Geography Publications and Other Works

Fire in Highland Pine Forests of the Dominican Republic―The Long View

Large forest fires in Valle Nuevo National Park in 2014 and 2015 have increased interest in fire as an ecological force in montane pine forests of the Dominican Republic. Geographer Dr. José Ramón Martínez Batlle estimated using Landsat imagery and GIS that some 4700 ha burned in July 2014 (http://www.geografiafisica.org/2014/07/29/superficie-quemada-incendio-valle-nuevo/), and an additional 1600 ha burned in late April 2015 (http://www.geografiafisica.org/2015/09/25/superficie-quemada-en-valle-nuevo-finales-de-abril-principios-de-mayo-2015/).

Since 1995, when I first visited what is today Valle Nuevo National Park (then, Valle Nuevo Scientific Reserve), as a guest of the Moscoso …

Limnología De Las Lagunas Glaciales En El Páramo Del Chirripó, Costa Rica. (Limnology Of Glacial Lakes In The Chirripó Páramo Of Costa Rica.), Sally P Horn, Kenneth H. Orvis, Kurt A. Haberyan

Geography Publications and Other Works

More than 30 lakes of glacial origin exist within the Chirripó páramo in the Cordillera de Talamanca of Costa Rica. This chapter describes the geomorphic setting and physical and chemical limnology of 19 lakes located between 3450-3570 m elevation in the upper basins of five glaciated valleys. All lakes are clear, dilute, and apparently polymictic. Water chemistry data from 1998, 2000, and 2001 are similar from lake to lake and year to year, and are consistent with sparse prior measurements between 1966 and 1991. However, the lake water temperatures we have measured are much higher than those reported by earlier …

Registros De Sedimentos Lacustres De La Vegetación Del Holoceno Y Historia Del Fuego En El Páramo De Costa Rica. (Lake-Sediment Records Of Holocene Vegetation And Fire History In The Costa Rican Páramos), Sally P Horn, Brandon L. League

Geography Publications and Other Works

We examined pollen, pteridophyte (ferns and fern-allies) spores, and charcoal in a 5.6 m long sediment core from Lago de las Morrenas 1, and charcoal in a 1.1 m long sediment core from Lago Chirripó, to reconstruct postglacial vegetation and fire history in the Chirripó páramo. Lago de las Morrenas 1, the largest lake in the Valle de las Morrenas of Chirripó National Park, is presently surrounded by treeless páramo vegetation and has apparently been so since deglaciation approximately 10,000 radiocarbon years ago. Pollen spectra suggest no pronounced changes in vegetation since ice retreat. Pollen percentages for Gramineae and other …