Relationships between Plant Biodiversity and Soil Fertility in a Mature Tropical Forest, Costa Rica

Abstract

We aimed to study relationships between plant biodiversity and soil chemical fertility in a mature tropical forest of Costa Rica. Soil samples were collected in nine sampling plots (5 m by 25 m) in order to identify P, K, Ca, Mg, Fe, Zn, Mn, Cu, and Al and total N contents, soil fertility index, CEC, pH, and C/N ratio. Furthermore, species richness, Shannon-Wiener and Simpson's species diversities, structural richness, and structural diversity were calculated for each plot. Simple linear regression analyses were conducted. Tree species richness was inversely related to concentration levels of K, Ca, and P, CEC, and soil fertility index. Therefore, higher tree species richness tended to be found on sites with lower soil fertility, which is the complete opposite of temperate forests. As a result, tropical and temperate forest ecology should be considered separately. Shannon-Wiener tree species diversity was positively correlated to C/N ratio. Herb structural richness was positively correlated with soil fertility index and P concentration. Therefore, herb structural richness may be a good indicator of soil fertility. This study gives important insights on ecological relationships between plant biodiversity and soil chemical fertility in a primary tropical forest.

Canonical Correlation Analysis across Vegetation and Soil Properties of the Disturbed and Undisturbed Coastal Forest Ecosystems

“…Interestingly, these variations can contribute into interpreting soil and diversity dynamics and complexity in agreement with [42,40]. Conversely, the observation trees stand parameters had no significant correlation with soluble bases agree the results of [39]. The implication of these findings in forest management is that some nutrients are affected more than others during and after disturbances.…”

“…These correlation values show that soil and above ground forest properties are characterized by the same dynamics directions in the coastal forests like in many other forest ecosystems [28,41]. The positive correlations in Shannon index and soluble bases, Shannon and soil physical properties, equitability and soil physical properties, independent value index and soil physical properties are important in showing that each kind of forest diversity is affected by soil factors contrary to observations made in [39]. This controversy is possibly resulting from variations in geographical locations and nature of vegetation.…”

“…Then this solution was put in the centrifuge at 8000 to 10000 rotation per minute, for about 10 minutes then a clear solution was decanted and the EC was measured in the decanted solution after calibrating the instrument by means of Potassium Chloride (0.01M KCl). The EC meter was used to get EC values [38,39,27].…”

Influencia de las condiciones edáficas sobre la dominancia y diversidad de árboles en bosques pluviales tropicales del Chocó biogeográfico.

“…Las condiciones edáficas han sido consideradas como un factor ambiental que explica significativamente la alta diversidad de especies arbóreas en bosques lluviosos tropicales (Huston, 1980;Gentry, 1981;Clark, Clark, & Read, 1998;Clark, 2002;Quinto & Moreno, 2014;Nadeau & Sullivan, 2015). Por ejemplo, Huston (1980Huston ( , 1994 sintetizó varios trabajos que proponen que la diversidad de plantas es baja en suelos pobres en nutrientes, aumenta conforme incrementa el nivel de nutrientes, y finalmente vuelve a disminuir cuando el suelo es muy fértil.…”

“…Asimismo, Huston (1980) evaluó la riqueza de especies arbóreas y su relación con los nutrientes del suelo en boques lluviosos tropicales de Costa Rica y encontró que la diversidad tiende a disminuir con la fertilidad del suelo (sumatoria de los porcentajes de P, K y Ca). En suelos pobres en nutrientes (P, K y Ca) se registra la mayor riqueza de especies arbóreas (Huston, 1980;Nadeau & Sullivan, 2015). Esta tendencia en diversidad arbórea también ha sido reportada por Faber-Langendoen y Gentry (1991), Clinebell, Phillips, Gentry, Stark, y Zuuring (1995), Duque, Cavelier, y Posada (2003), y Quinto y Moreno (2014), quienes han encontrado altos valores de riqueza de especies arbóreas en suelos pobres en nutrientes de diferentes regiones tropicales.…”