Rubber plantations act as water pumps in tropical China

Abstract

.[1] Whether rubber plantations have the role of water pumps in tropical Southeast Asia is under active debate. Fifteen years (1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008) of paired catchments water observation data and one year paired eddy covariance water flux data in primary tropical rain forest and tropical rubber plantation was used to clarify how rubber plantation affects local water resources of Xishuangbanna, China. Both catchment water observations and direct eddy covariance estimates indicates that more water was evapotranspired from rubber plantation (1137 mm based on catchment water balance, 1125 mm based on eddy covariance) than from the rain forest (969 mm based on catchment water balance, 927 mm based on eddy covariance). Soil water storage during the rainy season is not sufficient to maintain such high evapotranspiration rates, resulting in zero flow and water shortages during the dry season in the rubber plantation. Therefore, this study supports the idea that rubber plantations act as water pumps as suggested by local inhabitants.

Carbon Sequestration Potential and Edaphic Properties Along the Plantation Age of Rubber in Tripura, Northeastern India

“…The increase in soil moisture content with depth was may be due to the fact that in younger rubber plantation maximum root density is found in top 30 cm soil depth. Further the rubber plantation has other concerns over primary forest like high 15-17% high evapo-transpiration rate 13 . The physiology of the rubber tree is like that, it cannot hold the water in the tree 13 .…”

“…Further the rubber plantation has other concerns over primary forest like high 15-17% high evapo-transpiration rate 13 . The physiology of the rubber tree is like that, it cannot hold the water in the tree 13 .…”

“…Deforestation and burning of natural tropical forests have significant impact on the global carbon cycle by decreasing the above-and below-ground carbon stocks and by increasing rates of carbon emissions to the atmosphere 9 . The negative ecological and environmental implications of converting primary and secondary forests into rubber plantations have been suggested as loss of biodiversity 10 and total carbon biomass 11 , alteration of the hydrological cycle 8 and rapid soil erosion 12,13 . Globally, carbon stocks in terrestrial vegetation are 466 giga tons carbon and in the soil down to a depth of 1 meteris about 2011 giga tons carbon 14 .…”

Physiological mechanism for the reduction in soil water in poplar (Populus deltoides) plantations in Dongting Lake wetlands

“…The water-pumping effects of fast-growing tree plantations have been clarified in different ecosystems, such as in semiarid areas (Wilske et al 2009;Tan et al 2011) and wetlands (Le Maitre et al 2002;Hernández-Santana et al 2008;Migliavacca et al 2009). For example, poplar plantations have the potential to extract groundwater and to reduce the water table in wetland ecosystems (Migliavacca et al 2009).…”

“…Tree species used in plantations include eucalyptus (Gerber 2011), rubber (Tan et al 2011), pines (Licata et al 2008), and poplars (Perry et al 2001). Fast-growing trees are generally planted in monocultures, and these species have obvious advantages over native plants in competing for light, nutrients, and water resources.…”