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Journal articles on the topic 'Clay soils – Costa Rica'

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Author: Grafiati

Published: 10 December 2022

Last updated: 29 January 2023

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1

Chatterjee, Nilovna, P. K. Ramachandran Nair, Vimala D. Nair, Abhishek Bhattacharjee, Elias de Melo Virginio Filho, Rheinhold G. Muschler, and Martin R. A. Noponen. "Do Coffee Agroforestry Systems Always Improve Soil Carbon Stocks Deeper in the Soil?—A Case Study from Turrialba, Costa Rica." Forests 11, no. 1 (December 31, 2019): 49. http://dx.doi.org/10.3390/f11010049.

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Shaded perennial agroforestry systems (AFS) are regarded as desirable land-use practices that improve soil carbon sequestration. However, most studies assume a positive correlation between above ground and below ground carbon without considering the effect of past and current land management, textural variations (silt and clay percentage), and such other site-specific factors that have a major influence on the extent of soil C sequestration. We assessed SOC stock at various depths (0–10, 10–30, 30–60, and 60–100 cm) in shaded perennial coffee (Coffea arabica L.) AFS in a 17-year-old experimental field at the Centro Agronómico Tropical de Investigación y Enseñanza, (9°53′44′′ N, 83°40′7′′ W; soil type: Ultisols and Inceptisols, Turrialba, Costa Rica. The treatments included coffee (Coffea arabica L.) grown conventionally (with chemical fertilizers) and organically (without chemical fertilizers) under two shade trees, Erythrina poeppigiana (Walp.) O.F. Cook., and Terminalia Amazonia J.F.Gmel., Sun Coffee (Coffea arabica L.) (Sole stand of coffee without shade), and Native Forest. Three replicated composite soil samples were collected from each system for each depth class, and SOC stocks in three soil aggregate fractions (2000–250 µm, 250–53 µm, and <53 µm) and in the whole soil determined. The total SOC stocks were highest under forest (146.6 Mg C ha−1) and lowest under sun coffee (92.5 Mg C ha−1). No significant differences were noted in SOC stock within coffee AFS and sun coffee across fraction sizes and depth classes. Organic management of coffee under heavily pruned E. poeppigiana, with pruned litter returned to soil, increased SOC stocks for 0–10 cm depth soil only. High input of organic materials including pruned litter did not improve SOC stocks in deeper soil, whereas variations in silt and clay percentages had a significant effect on SOC stocks. The study suggests that high amounts of aboveground biomass alone are not a good indicator of increased SOC storage in AFS, particularly for soils of sites with historical characteristics and management similar to this study.

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2

Costa, Raimundo Nonato Távora, Daniel Santana Colares, Luís Carlos Uchôa Saunders, and Francisco De Souza. "ANÁLISE DAS EFICIÊNCIAS DE APLICAÇÃO E DE USO DA ÁGUA EM CULTIVO DE ARROZ NO PERÍMETRO IRRIGADO MORADA NOVA, CE." IRRIGA 10, no. 4 (December 22, 2005): 388–98. http://dx.doi.org/10.15809/irriga.2005v10n4p388-398.

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ANÁLISE DAS EFICIÊNCIAS DE APLICAÇÃO E DE USO DA ÁGUA EM CULTIVO DE ARROZ NO PERÍMETRO IRRIGADO MORADA NOVA, CE Raimundo Nonato Távora Costa1; Daniel Santana Colares1; Luís Carlos Uchôa Saunders1; Francisco de Souza21Departamento de Engenharia Agrícola, Universidade Federal do Ceará, Fortaleza, CE, rntcosta@fortalnet.com.br2Departamento Nacional de Obras Contra as Secas, Fortaleza, CE 1 RESUMO Os objetivos da pesquisa foram estudar a eficiência de aplicação e do uso da água do cultivo do arroz no perímetro irrigado Morada Nova, Ceará, no período de julho a dezembro de 2003. Estabeleceu-se a cultivar EPAGRI 109 em unidades de solo com texturas areia-franca, franca e argilo-siltosa. Utilizaram-se calhas Parshall e sifões de plástico como instrumentos para medição e aplicação de água aos tabuleiros. O período de irrigação do cultivo de arroz para as condições de solo e clima no perímetro irrigado Morada Nova situa-se em torno de 120 dias, período este que deve ser tomado como referência para o planejamento da irrigação. A eficiência de uso da água para os solos de textura leve apresentou valor médio de 0,2 kg.m-3; já para os solos de textura pesada, de 0,43 kg.m-3. A eficiência de aplicação de água na unidade textural argilo-siltosa, solo adequado ao cultivo de arroz apresentou um valor médio de 77%. Na unidade textural areia franca, porém, solo não recomendado para o cultivo do arroz, a eficiência de aplicação foi apenas de 38%. UNITERMOS: (Oryza sativa, L., irrigação, eficiência de aplicação. COSTA, R. N.T., COLARES, D.S., SAUNDERS, L.C.U., SOUZA, F.; EFFICIENCY OF WATER APLICATION AND USE FOR RICE IN MORADA NOVA IRRIGATION DISTRICT, CEARÁ 2 ABSTRACT Efficiency of water application and use for rice, cultivated from July to December 2003, was analyzed in Morada Nova Irrigation District, in Ceará – Brazil. Cultivar EPAGRI 109 was established in sandy-loan, loam and clay-loam soil units. Applied water was measured using Parshall flumes and sipluon tubes. Rice irrigation period for local climate and soil conditions was 120 days, also used for irrigation planning. Water use efficiency for sandy soils presented 0.2 kg.m-3 average values, while 0.43 kg.m-3 was the value for heavy soils. Application water efficiency for clay-loam soils, appropriate for rice, was 77%. However, for sandy soils – not recommended for rice – the water application efficiency was only 38%. KEYWORDS: (Oryza sativa, L.), irrigation, application efficiency

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3

Pincus, L. N., P. C. Ryan, F. J. Huertas, and G. E. Alvarado. "The influence of soil age and regional climate on clay mineralogy and cation exchange capacity of moist tropical soils: A case study from Late Quaternary chronosequences in Costa Rica." Geoderma 308 (December 2017): 130–48. http://dx.doi.org/10.1016/j.geoderma.2017.08.033.

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4

Ghanem, Simon J., Hans Ruppert, Thomas H. Kunz, and Christian C. Voigt. "Frugivorous bats drink nutrient- and clay-enriched water in the Amazon rain forest: support for a dual function of mineral-lick visits." Journal of Tropical Ecology 29, no. 1 (January 2013): 1–10. http://dx.doi.org/10.1017/s0266467412000740.

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Abstract:In Central Amazonia, large mammals create water-filled puddles when consuming soil. These mineral licks are visited by pregnant and lactating frugivorous bats; possibly for two reasons. Frugivorous bats could supplement their mineral-depleted fruit diet by drinking salty water, or they could buffer dietary plant secondary compounds by consuming soil. We analysed bat fruits from Ecuador and showed that they are depleted in elemental concentrations (Na, K, P) compared with similar fruits collected from Costa Rica, where no mineral licks occur (n = 32). Analyses of water from Ecuador revealed that water samples from six mineral licks contained more physiologically relevant elements (Na, K, Mg, Ca) than four samples from river and stream water control sites (Mann–WhitneyU-test). In support of the nutrient supplement hypothesis, we observed bats drinking mineral-enriched water at these licks (video observation). Furthermore, blood collected from 68 bats differed in composition with respect to physiologically relevant minerals (Na, K, Mg, Fe) from that of frugivorous bats captured at control sites. To test whether frugivorous bats also consumed clay for detoxification, we checked for soil tracer elements in 31 faecal samples. Soil tracers are insoluble in water and, thus, are not included in a strict fruit diet. Bats from mineral licks showed higher aluminium soil tracer concentrations in their faeces than bat species that never visit licks, suggesting that frugivorous bats take up clay material at mineral licks. Our results provide evidence that frugivorous bats ingest soluble mineral nutrients and insoluble soil by consuming soil-enriched water at mineral licks, thus supporting the hypothesis that frugivorous bats of western Amazonia may derive a dual benefit from drinking water from mineral licks.

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5

Araya, Mario, Alfonso Vargas, and Alexander Cheves. "Nematode distribution in roots of banana (Musa AAA cv. Valery) in relation to plant height, distance from the pseudostem and soil depth." Nematology 1, no. 7 (1999): 711–16. http://dx.doi.org/10.1163/156854199508739.

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AbstractThe horizontal and vertical distribution of plant parasitic root nematodes on banana (Musa AAA cv. Valery) was determined in a sandy clay loam in Costa Rica. Root samples were taken from soil blocks at distances of 0 to 30, 30 to 60, and 60 to 90 cm from the pseudostem, from 0 to 120 cm depth at intervals of 15 cm, and from plants of 120, 150, 180 or 210 cm high (non-flowering), plus a set from plants at flower stalk. The horizontal distance from the pseudostem affected the percentage of Radopholus similis, Pratylenchus spp., and total nematodes (R. similis + Helicotylenchus spp. + Meloidogyne spp. + Pratylenchus spp.). There was a significant effect of soil depth on the density of each genus. An interaction between soil depth and plant height and with horizontal distance was found for R. similis and total nematodes. For the three horizontal distances from the pseudostem, the percentage of each genus decreased with soil depth. Higher percentages of R. similis and total nematodes were found at 0 to 30 cm horizontal distance from the pseudostem than at greater distances in the upper 30 cm of the soil profile. Therefore, samples for monitoring nematode populations in bananas should be taken within a horizontal distance of 0 to 30 cm from the plant base and down to 30 cm deep from the soil surface. Additional studies are needed to relate the nematode population density at this sampling point to yield. Repartition des nematodes dans les racines du bananier (Musa AAA cv. Valery) en relation avec la hauteur de la plante, la distance au pseudo tronc et la profondeur du sol - La repartition horizontale et verticale des nematodes parasites du bananier (Musa AAA cv. Valery) a ete determinee dans un sol sablo-argileux, au Costa Rica. Les echantillons de racines ont ete preleves dans les blocs de sol extraits a differentes distances (de 0-30, de 30-60 et 60-90 cm) et profondeurs (de 0 a 120 cm avec des intervalles de 15 cm) du pseudo tronc des plantes: ces plantes, non encore fleuries, etaient de differentes hauteurs (120, 150, 180 et 210 cm). Quelques plantes entre le premier et le huitieme jour apres floraison ont egalement ete testees. La distance horizontale affecte le pourcentage de Radopholus similis et de Pratylenchus spp., et le nombre total de nematodes (R. similis + Helicotylenchus spp. + Meloidogyne spp. + Pratylenchus spp.). La profondeur du sol affecte la densite de population pour chaque genre. Pour R. similis et le nombre total de nematodes; il existe des interactions entre la profondeur du sol et la hauteur de la plante et entre la profondeur du sol et la distance horizontale. Le pourcentage de chacun des genres decroit avec la profondeur du sol aux trois distances au pseudo tronc. Les pourcentages les plus eleves de R. similis et du nombre total de nematodes ont ete trouves de 0 a 30 cm de profondeur. De ces resultats, il est conclu que pour etudier correctement les populations des nematodes du bananier, les echantillons de racines devraient ete preleves dans les premiers 30 cm de distance au pseudo tronc et jusqu'aux premiers 30 cm de profondeur du sol. Des etudes complementaires sont necessaires pour mieux etablir les rapports entre la densite des populations de nematodes dans ces points d'echantillonnage et le rendement.

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6

Morera, Jorge A. "Agricultura, recursos naturales, medio ambiente y desarrollo sostenible en Costa Rica." Agronomía Mesoamericana 11, no. 1 (January 1, 2006): 179. http://dx.doi.org/10.15517/am.v11i1.17453.

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The sustainable agriculture in Costa Rica must recognize the need of intensifying the productivity as a way to support the increasing demand created by the population growth, but at the same time it has to prevent the best use and conservation of the natural resources. Without natural resources there is no agriculture and without it there isn’t food support. It’s hoped that Costa Rica can satisfy the growing demand of food and other agriculture products; avoiding the fast process of degradation that our soils and forest are suffering. The sustainable agriculture process in Costa Rica and other countries of the region presents an increasing demand of land and natural resources; which causes social, economic and ecological conflicts and competence. This is why Costa Rica must organize a strategy of sustainable development that contemplates the effects of the demographic growth, food support, biodiversity protection, ecosystem regeneration, development of friendly technologies with the environment, regulation on the use of natural resources and the formation of better thought human beings.

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7

Bossew, P., and F. Strebl. "Radioactive contamination of tropical rainforest soils in Southern Costa Rica." Journal of Environmental Radioactivity 53, no. 2 (March 2001): 199–213. http://dx.doi.org/10.1016/s0265-931x(00)00126-0.

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8

Daly, Gillian L., Ying D. Lei, Camilla Teixeira, Derek C. G. Muir, Luisa E. Castillo, Liisa M. M. Jantunen, and Frank Wania. "Organochlorine Pesticides in the Soils and Atmosphere of Costa Rica." Environmental Science & Technology 41, no. 4 (February 2007): 1124–30. http://dx.doi.org/10.1021/es062349d.

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9

Paschke, Mark W., and Jeffrey O. Dawson. "The occurrence of Frankia in tropical forest soils of Costa Rica." Plant and Soil 142, no. 1 (April 1992): 63–67. http://dx.doi.org/10.1007/bf00010175.

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10

Aguilar, Steven, Julio E. Sánchez, and Daniel Martínez. "First record of Clay-colored Sparrow (Spizella pallida Swainson, 1832) (Aves: Emberizidae) in Costa Rica." Check List 9, no. 6 (December 1, 2013): 1592. http://dx.doi.org/10.15560/9.6.1592.

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We present the first record of the Clay-colored Sparrow (Spizella pallida) in Costa Rica. An adult bird was recorded ca. 900 Km south of its common wintering range. This represents the first record of the species for the country and for southern Central America.

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11

Kuehn, Rebecca, Michael Stipp, and Bernd Leiss. "Texture Development of Clay‐Rich Sediments Across the Costa Rica Subduction Zone." Journal of Geophysical Research: Solid Earth 124, no. 8 (August 2019): 7756–70. http://dx.doi.org/10.1029/2018jb016838.

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12

Saborío-Montero, Alejandro, Osvaldo Marín-Taylor, Randall Arguedas-Sánchez, and Sinaí Ramírez-Fallas. "Soil chemical fertility in dairy farms of the Guanacaste volcanic mountain range, Costa Rica." UNED Research Journal 7, no. 2 (December 15, 2015): 157–63. http://dx.doi.org/10.22458/urj.v7i2.1140.

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The aim of this research was to determine the fertility of soils of dairy farms at four zones of the Guanacaste volcanic mountain range. The study was conducted during a two-year period (2009-2010) in farms of Guayabo (Bagaces) and Nubes, San Ramón and Florida (Quebrada Grande, Tilarán). A total of 40 soil samples were collected, each one was composed by 20 sub- samples. The results revealed that soil pH in Guayabo tended to be lower (p=0.0539) than in Nubes, San Ramón and Florida. Guayabo soils showed higher concentrations (p<0.01) of magnesium (Mg), cupper (Cu), iron (Fe) and manganese (Mn) than the soils of the three zones of Tilarán. The soils of Guayabo and San Ramón showed higher values of effective cation exchange capacity (ECEC) (p<0.01) than Nubes and Florida soils. According to the general critical levels for the extracting solution used, none of the soils of the analyzed zones reach a pH higher than 5.5, the Tilarán and Guayabo soils were deficient in Mg and P respectively and no zone was deficient in Zn, Cu, Fe and Mn. These results revealed that the soils of all the zones had some mineral deficiency and low values of pH, therefore fertilizers and amendments should be applied according to nutritional needs of each farm. Adequate soil nutrition could improve productivity of forage and allowed a higher animal charge capacity per unit of area.

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13

Chin-Pampillo, Juan Salvador, Elizabeth Carazo-Rojas, Greivin Pérez-Rojas, Víctor Castro-Gutiérrez, and Carlos E. Rodríguez-Rodríguez. "Accelerated biodegradation of selected nematicides in tropical crop soils from Costa Rica." Environmental Science and Pollution Research 22, no. 2 (August 20, 2014): 1240–49. http://dx.doi.org/10.1007/s11356-014-3414-6.

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14

Pittl, Elisabeth, Gerd Innerebner, Wolfgang Wanek, and Heribert Insam. "Microbial communities of arboreal and ground soils in the Esquinas rainforest, Costa Rica." Plant and Soil 329, no. 1-2 (August 21, 2009): 65–74. http://dx.doi.org/10.1007/s11104-009-0134-7.

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15

Bertolani, Mario, and Anna G. Loschi Ghittoni. "Clay materials from the Central Valley of Costa Rica and their possible ceramic uses." Applied Clay Science 1, no. 3 (April 1986): 239–54. http://dx.doi.org/10.1016/0169-1317(86)90001-3.

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16

Montes de Oca, Paulina, Rafael Mata, and Marco A. Chaves. "Estudios de salinidad en la provincia de Guanacaste (Costa Rica) y caracterización de algunos suelos con influencia salina." Agronomía Mesoamericana 7, no. 2 (June 2, 2016): 77. http://dx.doi.org/10.15517/am.v7i2.24766.

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The soils wich are affected by salts are developing preferently in regions where the precipitation is limited, the temperature is high and the conditions of drainage are restricted like in some soils of Guanacaste's area. A bibliography review about some soils with high salts contents was made in Ing. Taboga, Guanacaste's area. Two soils samples was taking classified in Typic hapluster and Fluventic ustropept. There are analized with methods that caracterize the salinity of soils jour with the technics of rutinary analysis.

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17

Hernández, Juan Carlos, Rodolfo Araya, and Adriana Morales. "Bribri, nueva variedad de frijol rojo pequeño para Costa Rica." Agronomía Mesoamericana 12, no. 1 (January 1, 2006): 15. http://dx.doi.org/10.15517/am.v12i1.17242.

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The line MD 23-24 was introduced and tested in Costa Rica between 1996 and 1999, which served as the precursor of the Bribri bean variety. It was bred, at the Escuela Agrícola Panamericana Zamorano, by crossing (RAB 310/XAN 155) X (DOR 391/POMPADOUR G). The variety characterizes by showing a small bright red grain, with a II-B Type growth habit, an erect bearing and a vegetative cycle from 76-80 days. The two main life zones where it was evaluated were the bh-T (tropical humid forest) and the bmh-P (very humid pre-mountainous forest). Small commercial farms with low fertility soils prevailed in most of the evaluated localities. The Bribri variety outstood in average yield by 17.2% the national control and by 13,4% the local control. Its yield was 8.5% higher than the average yield of all the assays. The verifying and the validation stages were conducted based on the technology applied by the farmers in nine out of eleven localities. Bribri out-yielded the local controls in 67% of the plots at the verifying phase (with an average of 15.5% more kg/ha) and in 80% of the validation plots (with an average of 7.5% more kg/ha). Besides, it showed tolerance to web-blight (Thanatephorus cucumeris (A.B. Frank) Donk).

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18

Saenz, Fernando, and Ruerd Ruben. "Export contracts for non-traditional products: Chayote from Costa Rica." Journal on Chain and Network Science 4, no. 2 (December 1, 2004): 139–50. http://dx.doi.org/10.3920/jcns2004.x048.

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This paper focuses on the determinants of market and contract choice for non-traditional crops and the possibilities for involving local producers in global agro-food chains through delivery relationships with packers and brokers. Main attention is given to the importance of quality for entering the export market and the impact of contractual arrangements on loyal behaviour. Core stipulations in the contract regarding the frequency of delivery and the provision of technical assistance are mediating factors between quality and loyalty. The study among traditional and recently established producers of chayote in Costa Rica confirms the importance of production scale and experience for engagement in exports. The export share is positively related to quality performance but inversely related to delivery frequency and sales at the local market. Apparently, traditional producers rely on market diversification to maintain a certain bargaining power vis-à-vis traders and processors. Verbal contractual arrangements are mainly offered to newly established but less-experienced farmers living in settlements that try to reduce risk and demonstrate a high commitment. These farmers cultivate on better soils and have more family labour available. Further quality improvement requires technical assistance and a high frequency of delivery. Supplier arrangements that guarantee timely collection, input support and flexible credit services are therefore of critical importance. Additional support from packers and exporters could enable farmers to improve product quality and is likely to be rewarded. with a high degree of loyalty.

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19

Vitousek, Peter M., and Julie S. Denslow. "Differences in Extractable Phosphorus Among Soils of the La Selva Biological Station, Costa Rica." Biotropica 19, no. 2 (June 1987): 167. http://dx.doi.org/10.2307/2388740.

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20

Tilki, Fahrettin, and Richard F. Fisher. "Tropical leguminous species for acid soils: studies on plant form and growth in Costa Rica." Forest Ecology and Management 108, no. 3 (August 1998): 175–92. http://dx.doi.org/10.1016/s0378-1127(98)00225-4.

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21

Becklund, Kristen K., Linda L. Kinkel, and Jennifer S. Powers. "Landscape-scale Variation in Pathogen-suppressive Bacteria in Tropical Dry Forest Soils of Costa Rica." Biotropica 46, no. 6 (October 30, 2014): 657–66. http://dx.doi.org/10.1111/btp.12155.

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22

Echeverría-Beirute, Fabián, Ingrid Varela-Benavides, Jose P Jiménez-Madrigal, Milagro Carvajal-Chacon, and Tomás Guzmán-Hernández. "eDNA extraction protocol for metagenomic studies in tropical soils." BioTechniques 71, no. 6 (December 2021): 580–86. http://dx.doi.org/10.2144/btn-2021-0057.

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The lack of knowledge about biological communities residing in soils, especially those in tropical regions, represents a constraint to management practices to take advantage of the ecological services provided by soil microbiota to agroecosystems. One of the complexities derived from describing biological diversity in such tropical conditions comes from the methods used to isolate microorganisms without altering the composition of the sample. The goal of this study was to establish a protocol for adequate soil sampling and environmental DNA extraction from a tropical region in Costa Rica. We present an up-to-date protocol optimized for tropical soils which improves sevenfold the amount of DNA extracted without significantly affecting the 260/280 and 260/230 ratios compared with commercially available kits and standard protocols.

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23

Araya, Rodolfo, and Jorge A. Acosta. "Adaptación del frijol a suelos de baja fertilidad bajo presión de enfermedades foliares en Costa Rica." Agronomía Mesoamericana 11, no. 2 (July 1, 2006): 31. http://dx.doi.org/10.15517/am.v11i2.17303.

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The aim of this study was to identify bean genotypes with high yield potential when grown in soils of low fertility and under the pressure of foliar diseases. Diverse genotypes, known for its adaptation in soils of low fertility and/or resistance to other biotic and abiotic stresses were evaluated in the field during 1996 and 1997. In total, 562 genotypes, 251 bred and 311 landraces, were evaluated in two locations in Costa Rica: Fraijanes (1750 msnm; 15.3 °C; 3025 mm annual precipitation; 10º09’ North and 84°12’ West); and Alajuela (840 msnm, 23,1 °C; 1966 mm annual precipitation; 10°01’ North and 84° 16’ West). Plant stand was of 15 seeds per lineal m and plot size was variable due to seed availability; at planting inoculant of Rhizobium tropici was added directly onto the seed in the row (4 kg/ha). Bred line A 321, the control genotype UCR 55, A 483, G11640, G19696, G10843 and BAC50 displayed high yields in both locations. Genotypes that showed high yield in only one location were, in Alajuela: Guanajuato 132, Negro INIFAP, VAX 2 and MAR 3; in Fraijanes higher yielders were G13860, G92, MOC 112, Bayo Alteño, J 117; Negro 8025 and A 247. Outstanding landraces and bred lines from diverse geographical areas and genetic pools that displayed adaptation in soils of low fertility were identified in germplasm introduced from CIAT, México, Perú and Guatemala. It is emphasized the importance of evaluating native material and the exchange of germplasm among countries. Superior genotypes will be used for bean breeding in low input agriculture.

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24

Kesel, R. H., and B. E. Spicer. "Geomorphologic relationships and ages of soils on alluvial fans in the Rio General Valley, Costa Rica." CATENA 12, no. 1 (January 1985): 149–66. http://dx.doi.org/10.1016/s0341-8162(85)80014-x.

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25

Powers, Jennifer S., and William H. Schlesinger. "Geographic and vertical patterns of stable carbon isotopes in tropical rain forest soils of Costa Rica." Geoderma 109, no. 1-2 (September 2002): 141–60. http://dx.doi.org/10.1016/s0016-7061(02)00148-9.

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26

Kesel, R. H., and B. E. Spicer. "Geomorphologic relationships and ages of soils on alluvial fans in the Rio General Valley, Costa Rica." CATENA 12, no. 2-3 (June 1985): 149–65. http://dx.doi.org/10.1016/0341-8162(85)90007-4.

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27

Montagnini, Florencia, Freddy Sancho, and Haworth Continuing Features Submission. "Aboveground Biomass and Nutrients in Young Plantations of Indigenous Trees on Infertile Soils in Costa Rica." Journal of Sustainable Forestry 1, no. 4 (May 23, 1994): 115–39. http://dx.doi.org/10.1300/j091v01n04_06.

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28

Rojas-Barrantes, Martín, and Mario Fernández-Arce. "Volcanic Deposits and Volcanic Hazard in Santo Domingo de Heredia, Costa Rica." Journal of Geography and Geology 8, no. 2 (June 4, 2016): 111. http://dx.doi.org/10.5539/jgg.v8n2p111.

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The present research aims to investigate more precisely about the geology of the Eastern region of the Santo Domingo County. Santo Domingo is part of the structural plateau in the center of Costa Rica, which is located at the foot of the Cordillera Volcánica Central (CVF) [Central Volcanic Front] and is covered by volcanic deposits. On this plateau, called Central Valley, is the highest percentage of the population of the country and therefore, a large sector of the Costa Rican population is exposed to volcanic eruptions of the volcanoes in the CVF. For existing the national system for risk management and a law that demands actions to local authorities to prevent and mitigate disaster, it is necessary to identify the threats that exist in the cantons (counties) of Costa Rica. This will serve to take the prevention and mitigation actions necessary to reduce the impact of volcanic eruptions in the area of Santo Domingo.The research method consisted of review and analysis of previous works through literature research, data collection and analysis of boreholes from records of water-supply wells and open pits, and field work to better know the geology of the area. The results indicate that there are deposits of powerful volcanic eruptions of pyroclastic fall deposits (volcanic ash and lapilli) that mostly form clayey soils and lahars deposits that practically covers the entire territory. Underlying these deposits there is a pyroclastic flow deposit (ignimbrite), followed by lapilli tephra (a layer of pumice of at least 2 meters thick) that mark a change in the volcanic activity. Such pyroclastic flow is overlaid by an igneous presumably sub-volcanic activity of andesites interlayered with ancient tuffs, with a considerable thickness of over 350 meters according with borehole data and the exposure recognition on Pará river study sites. According to site locations (P1 to P23) of volcaniclastic deposits, there is evidence of an important environmental impact caused by the last eruptions of the CVF volcanoes. The real and current volcanic threat to the population of the County is the fall-out of ash emitted from the Turrialba and Irazú volcanoes. From local observations along the Virilla and Pará rivers sections, there is no evidence of younger pyroclastic flows overlying the volcanic sequence.

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Looby, Caitlin I., Emily C. Hollenbeck, and Kathleen K. Treseder. "Fungi in the Canopy: How Soil Fungi and Extracellular Enzymes Differ Between Canopy and Ground Soils." Ecosystems 23, no. 4 (September 16, 2019): 768–82. http://dx.doi.org/10.1007/s10021-019-00439-w.

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Abstract Tropical montane cloud forests contain a large abundance and diversity of canopy epiphytes, which depend on canopy soil to retain water and nutrients. We lack an in depth understanding of how these soils contribute to ecosystem processes and soil diversity and how sensitive they may be to projected climate change. We compared canopy and ground soils in Monteverde, Costa Rica, to determine how these two soil types differ in their extracellular enzyme activity (EEA) and fungal communities. Samples were also collected along two elevation gradients to reveal if canopy soils differed in how EEA and fungal communities responded to elevation compared to ground soils. We found that canopy soils had higher EEA than ground soils. Fungal communities were less diverse and differed significantly between the two soil types. These differences were associated with higher relative abundances of yeasts and endophytes in canopy soils. The relative abundances of free-living filamentous fungi and yeasts shifted more dramatically with elevation in canopy soils compared to ground soils. Our study suggests that canopy soils may be a reservoir for endophytes. Epiphytes may invest in symbionts that promote stress tolerance over mycorrhizal fungi whose high resource demands are costly and less beneficial. Overall, soils harbor distinct fungal communities that may be altered under projected climate change.

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Alvarado, Alfredo, Argenis Mora, Eduardo Chacón, José Villalobos, and Carlos Sandí. "Concentración foliar de macro- y micro-nutrimentos en cuatro leguminosas maderables del trópico estacionalmente seco de Costa Rica." Revista de Biología Tropical 66, no. 3 (July 4, 2018): 969. http://dx.doi.org/10.15517/rbt.v66i3.29838.

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The information about nutritional aspects of trees in the tropical dry forest is scarce. This investigation aims to establish a normal range of foliar nutrient concentration to four forestry species as related to their growth rates and biological nitrogen fixation capacity in the seasonally dry ecosystem at Guanacaste, Costa Rica. Foliar samples for four species, Dalbergia retusa (cocobolo), Enterolobium cyclocarpum (guanacaste), Hymenaea courbaril (guapinol or jatobá) and Schizolobium parahyba (gallinazo or pachaco), all belonging to the Fabaceae family, were analyzed for N, P, Ca, Mg, K, S, Fe, Mn, Cu, Zn, B and Na. Nutrient concentration varied with species according to their ability to fix nitrogen and their rate of growth. The overall concentration of macronutrients was higher in nitrogen-fixing species compared with non-fixing species, and within each one of those groups, the species with higher growth rate presented more macronutrients than species with low growth rate. According to the concentration of foliar nutrients accumulated in the foliage, we recommend that H. courbaril and D. retusa could be grown in the region soils with medium fertility and E. cyclocarpum and S. parahyba in the more fertile soils. Values ranges of foliar concentrations considered as satisfactory presented in this work are new for D. retusa and H. courbaril and improve the scarce information available for E. cyclocarpum and S. parahyba.

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Veldkamp, Edzo, Michael Keller, and Marvin Nuñez. "Effects of pasture management on N2O and NO emissions from soils in the humid tropics of Costa Rica." Global Biogeochemical Cycles 12, no. 1 (March 1998): 71–79. http://dx.doi.org/10.1029/97gb02730.

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Thrupp, Lori Ann. "Long-term losses from accumulation of pesticide residues: a case of persistent copper toxicity in soils of Costa Rica." Geoforum 22, no. 1 (January 1991): 1–15. http://dx.doi.org/10.1016/0016-7185(91)90026-m.

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Spaans, E. J. A., G. A. M. Baltissen, J. Bouma, R. Miedema, A. L. E. Lansu, D. Schoonderbeek, and W. G. Wielemaker. "Changes in physical properties of young and old volcanic surface soils in Costa Rica after clearing of tropical rain forest." Hydrological Processes 3, no. 4 (October 1989): 383–92. http://dx.doi.org/10.1002/hyp.3360030409.

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34

Eaton, William D., Katie M. McGee, Elizabeth Hoke, Alex Lemenze, and Mehrdad Hajibabaei. "Influence of Two Important Leguminous Trees on Their Soil Microbiomes and Nitrogen Cycle Activities in a Primary and Recovering Secondary Forest in the Northern Zone of Costa Rica." Soil Systems 4, no. 4 (November 6, 2020): 65. http://dx.doi.org/10.3390/soilsystems4040065.

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Inga edulis and Pentaclethra macroloba are dominant N-fixing forest trees in Costa Rica, likely important for recovery of soil N and C after deforestation, yet little is known of their soil microbiomes nor how land use impacts them. Soils from both trees in a primary and secondary forest were assessed for N-cycle metrics and DNA sequence-based composition of total bacterial, potential N-fixing bacterial, and potential ammonium oxidizing bacterial genera. The compositions of the functional groups of bacteria, but not their total relative abundance of DNA, were different across the soils. The P. macroloba soils had greater NO3− levels and richness of both functional groups, while I. edulis soils had greater NH4+ levels, consistent with its NH4+ preference for root nodule development. The bacterial communities were different by habitat, as secondary forest I. edulis microbiomes were less rich, more dominant, possibly more affected by the disturbance, or reached equilibrium status quicker than the richer, less dominant P. macroloba microbiomes, which may be developing slower along with secondary forest succession, or were less affected by the disturbance. Functional redundancy and switching of 10 N-cycle bacterial genera was evident between the primary and secondary forest soils, likely to maintain stable levels of N-cycle activity following disturbance. In summary, the two tree soil microbiomes are different, land use differentially affects them, and, thus, both tree species should be used during forest regeneration strategies in this region.

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Kleber, Markus, Luitgard Schwendenmann, Edzo Veldkamp, Jenny Rößner, and Reinhold Jahn. "Halloysite versus gibbsite: Silicon cycling as a pedogenetic process in two lowland neotropical rain forest soils of La Selva, Costa Rica." Geoderma 138, no. 1-2 (February 2007): 1–11. http://dx.doi.org/10.1016/j.geoderma.2006.10.004.

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García, Francisco Javier López, and Juan Guillermo Cruz Castillo. "YIELD OF Coffea arabica GRAFTED ONTO Coffea canephora IN SOILS INFESTED WITH NEMATODES IN MEXICO." Coffee Science 14, no. 3 (September 25, 2019): 308. http://dx.doi.org/10.25186/cs.v14i3.1579.

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The total of three consecutive years of fruit production was evaluated in six coffee cultivars (<em>Coffea arabica L</em>.) propagated by seed and grafted onto Robusta (<em>Coffea canephora</em> var. Robusta). The plantations were established at 640 m, 920 m, and 1340 m altitude in the central region of the Veracruz State, Mexico. The <em>coffea</em> plants were established in soils naturally infested with nematodes. Grafted plants had higher production than those propagated by seed. Fruit production was higher at 640 m and 920 m than at 1340 m for the two types of propagation. The cultivars Colombia Brote Café and Colombia Brote Verde had the highest fruit yield regardless of the propagation methods; in contrast, Pacamara, had the lowest. The grafted coffee plants that were planted at 1340 m had a yield reduction of 27% in comparison with those at 640 and 920 m. When the Costa Rica 95 variety was grafted, it achieved fruit yield similar to Colombia Brote Verde and Colombia Brote Café. Pacamara produced almost 28% more fruit when it was grafted onto Robusta.

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Becknell, Justin M., and Jennifer S. Powers. "Stand age and soils as drivers of plant functional traits and aboveground biomass in secondary tropical dry forest." Canadian Journal of Forest Research 44, no. 6 (June 2014): 604–13. http://dx.doi.org/10.1139/cjfr-2013-0331.

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The distribution of tropical forest biomass across the landscape is poorly understood, particularly in increasingly common secondary tropical forests. We studied the landscape-scale distribution of edaphic properties, plant community characteristics, and aboveground biomass (AGB) in secondary tropical dry forests in northwest Costa Rica. We used structural equation modeling to examine conceptual models of relationships among these factors, with data from 84 0.1 ha plots. Stand age and soils explained 33%–60% of the variation in community-weighted mean values of foliar traits including specific leaf area, foliar nitrogen, phosphorus, and δ13C. Aboveground biomass ranged from 1.7 to 409 Mg·ha−1 among plots between 5 and >100 years old. Stand age alone explained 46% of the variation in AGB among plots, while a model including age, soil pH, traits, and forest type explained 58%. Stand age was the most important variable explaining the distribution of AGB and community characteristics in secondary forests. We speculate that plot size, landscape heterogeneity, disturbance history, and stand dynamics contribute to the unexplained variation in AGB across the landscape.

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Ramírez, Lenín, Alfredo Durán, and Dennis Mora. "Combate integrado de la pudrición radical de la papaya (Phytophthora sp.) a nivel de vivero." Agronomía Mesoamericana 9, no. 1 (May 31, 2016): 72. http://dx.doi.org/10.15517/am.v9i1.24645.

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The effect of several strategies - alone and integrated - on the control of the Phytophthora sp. fungae, which causes radical rotting of papaya fruits, was evaluated under nursery conditions. The experiment took place between August 1994 and March 1995 at the University of Costa Rica's Estación Experimental Fabio Baudrit, located in Alajuela, Costa Rica. The treatments applied were: sun heat for 30 days; organic fertilizer made from hen droppings; etridiazole fungicide; and the following combinations: sun heat + etridiazole + organic fertilizer; etridiazole + organic fertilizer; sun heat + etridiazole; sun heat + etridiazole + organic fertilizer, and finally, an inoculated control treatment. Soil rows were made, and then they were innoculated with the pathogenic agent, and finally the aforementioned treatments were applied. The treated soils were bagged separately. The Solo Sunrise Hawaiian variety was planted in bags. The percentage of gerrnination, stem diameter at soillevel, plant height, radical system fresh weight, and severity of radical rotting were evaluated three months later. In addition, the effect of the treatments on beneficent soil microorganism populations (actinomyces, protozoa, bacteria, and fungi) was evaluated, as well as those of pathogenic populations. Organic fertilizer increased plant strength. All treatments affected germination; the innoculated control had the greatest germination percentage. Treatments containing organic fertilizer affected germination most.

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Shebitz, Daniela J., and William Eaton. "Forest Structure, Nutrients, and Pentaclethra macroloba Growth after Deforestation of Costa Rican Lowland Forests." ISRN Ecology 2013 (April 17, 2013): 1–10. http://dx.doi.org/10.1155/2013/414357.

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Succession following deforestation in Neotropical forests has been investigated extensively, yet rarely have studies connected nutrient dynamics with vegetation. This study was conducted in lowland wet forests of Maquenque, Costa Rica. The objectives were (1) to compare carbon (C), nitrogen (N), and phosphorus (P) characteristics and understory vegetation diversity between regenerating forests and primary forests; and (2) to use these variables to evaluate P. macroloba’s successional role. Four 300 m2 plots were established in primary and secondary forests where P. macroloba was the dominant N-fixing tree. Soil and vegetation data were collected from 2008 to 2010. Values of indicators of C, N, and P cycle activity were generally greater in primary than in secondary forest soils. Efficiency of organic C use and the relative contribution of respiration and organic C to soil biomass were also greater in the primary forest. These trends corresponded with greater richness, biomass, and cover of total and leguminous plant species, greater volume of P. macroloba in primary stands, and greater density of P. macroloba in secondary stands. As cleared regions of former primary forest regenerate, P. macroloba is the important dominant N-fixing tree and a critical driver of C, N, and P recuperation and ecosystem recovery.

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Stoorvogel, J. J., R. A. Schipper, and D. M. Jansen. "USTED: a methodology for a quantitative analysis of land use scenarios." Netherlands Journal of Agricultural Science 43, no. 1 (March 1, 1995): 5–18. http://dx.doi.org/10.18174/njas.v43i1.581.

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Scenarios are a useful tool to study the effects of changes in the socio-economic and/or biophysical environment on agricultural land use. For the analysis of these scenarios an operational methodology, USTED, has been developed. The methodology is based on a linear programming model in combination with GIS, crop growth simulation models, and expert systems. The data requirements include quantitative descriptions of land use systems and technologies, attribute data on such features as prices and chemical compositions, and georeferenced data on farms and soils. Sustainability is incorporated in the methodology by a limited number of quantified sustainability parameters. The linear programming model analyses, on the basis of different farm types, the effect of different scenarios on land use. Customized computer software (MODUS) is used to integrate the different models. The methodology is illustrated with a case study for the Neguev settlement in the Atlantic Zone of Costa Rica.

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Hargis, Hailey, Sybil G. Gotsch, Philipp Porada, Georgianne W. Moore, Briana Ferguson, and John T. Van Stan. "Arboreal Epiphytes in the Soil-Atmosphere Interface: How Often Are the Biggest “Buckets” in the Canopy Empty?" Geosciences 9, no. 8 (August 5, 2019): 342. http://dx.doi.org/10.3390/geosciences9080342.

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Arboreal epiphytes (plants residing in forest canopies) are present across all major climate zones and play important roles in forest biogeochemistry. The substantial water storage capacity per unit area of the epiphyte “bucket” is a key attribute underlying their capability to influence forest hydrological processes and their related mass and energy flows. It is commonly assumed that the epiphyte bucket remains saturated, or near-saturated, most of the time; thus, epiphytes (particularly vascular epiphytes) can store little precipitation, limiting their impact on the forest canopy water budget. We present evidence that contradicts this common assumption from (i) an examination of past research; (ii) new datasets on vascular epiphyte and epi-soil water relations at a tropical montane cloud forest (Monteverde, Costa Rica); and (iii) a global evaluation of non-vascular epiphyte saturation state using a process-based vegetation model, LiBry. All analyses found that the external and internal water storage capacity of epiphyte communities is highly dynamic and frequently available to intercept precipitation. Globally, non-vascular epiphytes spend <20% of their time near saturation and regionally, including the humid tropics, model results found that non-vascular epiphytes spend ~1/3 of their time in the dry state (0–10% of water storage capacity). Even data from Costa Rican cloud forest sites found the epiphyte community was saturated only 1/3 of the time and that internal leaf water storage was temporally dynamic enough to aid in precipitation interception. Analysis of the epi-soils associated with epiphytes further revealed the extent to which the epiphyte bucket emptied—as even the canopy soils were often <50% saturated (29–53% of all days observed). Results clearly show that the epiphyte bucket is more dynamic than currently assumed, meriting further research on epiphyte roles in precipitation interception, redistribution to the surface and chemical composition of “net” precipitation waters reaching the surface.

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42

Stanley, William G., and Florencia Montagnini. "Biomass and nutrient accumulation in pure and mixed plantations of indigenous tree species grown on poor soils in the humid tropics of Costa Rica." Forest Ecology and Management 113, no. 1 (January 1999): 91–103. http://dx.doi.org/10.1016/s0378-1127(98)00417-4.

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43

Toohey, Ryan C., Jan Boll, Erin S. Brooks, and Jeffrey R. Jones. "Effects of land use on soil properties and hydrological processes at the point, plot, and catchment scale in volcanic soils near Turrialba, Costa Rica." Geoderma 315 (April 2018): 138–48. http://dx.doi.org/10.1016/j.geoderma.2017.11.044.

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44

Montagnini, Florencia, and Freedy Sancho. "Net nitrogen mineralization in soils under six indigenous tree species, an abandoned pasture and a secondary forest in the atlantic lowlands of costa rica." Plant and Soil 162, no. 1 (May 1994): 117–24. http://dx.doi.org/10.1007/bf01416097.

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45

Villagra-Mendoza, Karolina, Federico Masís-Meléndez, Jaime Quesada-Kimsey, Carlos A. García-González, and Rainer Horn. "Physicochemical Changes in Loam Soils Amended with Bamboo Biochar and Their Influence in Tomato Production Yield." Agronomy 11, no. 10 (October 13, 2021): 2052. http://dx.doi.org/10.3390/agronomy11102052.

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Soil degradation and water stress in Costa Rica challenge the production of highly sensitive crops. This work is aimed at evaluating the physical and chemical changes in sandy loam (SL) and a silt loam (SiL) soil when amended with bamboo biochar while estimating the enhancement of tomato productivity. Biochar, obtained from Guadua Angustifolia bamboo feedstock, was mixed into sieved bulk soil substrate from the topsoil, from Andosol and Umbrisol groups, at application rates of 1, 2.5, and 5% (dry mass). Physicochemical and morphological properties of biochar such as pH, hydrophobicity, scanning electron microscopy images, helium picnometry, specific surface area by the Brunauer–Emmett–Teller (BET) method, CHNS, and ash content were determined. Soil hydrophobicity, acidity, electrical conductivity, cation exchange capacity and water retention, available water content, and air capacity were analyzed for the amended soils. Tomato yield was quantified after a harvest period of two months. The admixture of biochar did not significantly increase soil cation exchange capacity but increased water retention in the range of available water content. Class A (>200 g) tomato yield increased 350% in the SL and 151% in the SiL. Class B (100–200 g) tomato yields increased 27% in the SL but decreased about 30% in the SiL. Tomato yield response seems attributable to variation of water retention capacity, available water content, and air capacity. These results support the use of adapted water management strategies for tomato production based on soil physical changes of biochar.

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Triska, Frank J., Catherine M. Pringle, Gary W. Zellweger, John H. Duff, and Ronald J. Avanzino. "Dissolved Inorganic Nitrogen Composition, Transformation, Retention, and Transport in Naturally Phosphate-Rich and Phosphate-Poor Tropical Streams." Canadian Journal of Fisheries and Aquatic Sciences 50, no. 3 (March 1, 1993): 665–75. http://dx.doi.org/10.1139/f93-077.

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The composition, transformation, and transport of dissolved inorganic nitrogen (DIN) was compared in waters associated with two lowland streams in Costa Rica. The Salto River is enriched by geothermal-based soluble reactive phosphorus (SRP), which raises the concentration up to 200 μg/L whereas Pantano Creek, an unimpacted tributary, has an SRP concentration <10 μg/L. Ammonium concentration in springs adjacent to the Salto and Pantano was typically greater than channel water (13 of 22 locations) whereas nitrate concentration was less (20 of 22 locations). Ground waters were typically high in ammonium relative to nitrate whereas channel waters were high in nitrate relative to ammonium. Sediment slurry studies indicated nitrification potential in two sediment types, firm clay (3.34 μg N∙cm−3∙d−1) and uncompacted organic-rich sediment (1.76 μg N∙cm−3∙d−1). Ammonium and nitrate amendments to each stream separately resulted in nitrate concentrations in excess of that expected after correction for dilution using a conservative tracer. SRP concentration was not affected by DIN amendment to either stream. SRP concentration in the Pantano appeared to be regulated by abiotic sediment exchange reactions whereas DIN composition and concentration were regulated by a combination of biotic and abiotic processes.

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Baraona, Marcia, and German Rivera. "Desarrollo del jocote (Spondias purpurea L.) y del cas (Psidium friedrichstlzalianum (Berg.) Niedz) en el bosque húmedo premontano de Costa Rica." Agronomía Mesoamericana 6 (June 2, 2016): 23. http://dx.doi.org/10.15517/am.v6i0.24804.

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The objetive of this experiment was to study the adaptation of both tree species to agro-ecological conditions and to determine the fruit yield reducing factors. Soil type was a stony andisol. The sour guava experimental plot, consisted of ungrafted trees (15 years old average). Phenological studies have beenconducted and production indexes determined during the last three years. Pest incidence on buds, flowers and fruits was also observed. The heaviest blooming was in March and July, with little variation from year to year. Fruit production was concentrated in March, November and December. All trees reduced fruit production during the dry season. Fruit set varied from 0 to 12% depending on the season and individual tree. The average fruit production was 30 kg/tree, but in better quality soils around the same area yields reached 40 kg/tree. A sample of 200 fruits was evaluated and classified as follows: first class 14%, rejects 26% (because of overripening, fungal infections, trips, crakings and presence of fruit flies' larvae. The spanish plum, "tronador" type, plot was three and one half years old. They were propagated by cuttings, and planted 4x4 meters, and pruned twice a year. Their branches were ringed. The trees bloomed at the end of March, after a defoliation period whieh lasted until the end of May. Prunings at the begining of Marchdelayed blooming and fruit set. Flowers were produced in axilar panicles in variable numbers. Each panicle set one to three fruits. First harvest was at their third year and fruit numbers fluctuated from 20 to 140 fruits per tree. They were pruned during the last-quarter moon. The first two years' shape prunnings were done as tip cuttings. The spanish plum produced more secondary branches when tips were cut oof or branches ringed, and the resulting small branches were the productive ones. The foliage was usually pest free, except for so me aphids and worms. Fruits showed a heavy attack of unknown trip and mite species.

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Durán, Norberto, and Rubén A. Ortíz. "Efectos de algunas propiedades físicas del suelo y la precipitación sobre la producción de la palma aceitera (Elaeis guineensis) en Centroamérica." Agronomía Mesoamericana 6 (June 2, 2016): 07. http://dx.doi.org/10.15517/am.v6i0.24802.

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The soil aeration and hydric shortage greatly influence oil palm yield in Central America. This assay was conducted to identify and quantify the effect of the physical properties of the soil and rainfall on the yield of oil palm orchards in Coto and Quepos (Costa Rica) and San Alejo (Honduras). The following soil characteristics were evaluated: texture, moisture retention (pF), gravimetric moisture, drain water, total porosity, aerial space, large pore percentage, penetration resistance and tensimeter readings. These evaluations were conducted on 20 fruit bearing plots (in each locality) located within representative soil units; classified as: a) well drained (Fluventic Eutropepts), b) inperfect or moderately drained (Fluvaquentic Eutropepts) and c) poorly drained (Tropaquepts). San Alejo also shows soils with low base saturation (Dystropepts and Psamments). Twenty four additional plots were analyzed in this latter orchard to relate their yield with the catographic units. Regression and corre lation analysis were run for the three localities. The main limiting factors on production were: poor soil aeration en Coto, poor soil aeration and hydric shortage en Quepos, and poor aeration, low base saturation and sandy textures in San Alejo.

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Tanner, Lawrence H., David L. Smith, Jessica Curry, and Justin Twist. "Effect of Land Use Change on Carbon Content and CO<sub>2</sub> Flux of Cloud Forest Soils, Santa Elena, Costa Rica." Open Journal of Soil Science 04, no. 02 (2014): 64–71. http://dx.doi.org/10.4236/ojss.2014.42009.

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Messenger, A. Steven, Jose F. Di Stefano, and Luis A. Fournier. "Rooting and Growth of Cuttings ofBursera simarouba, Gliricidia sepium, andSpondias purpureain Upland Stony, Upland Non-Stony and Lowland Non-Stony Soils in Ciudad Colon, Costa Rica." Journal of Sustainable Forestry 5, no. 3-4 (April 10, 1997): 139–51. http://dx.doi.org/10.1300/j091v05n03_08.

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