Microclimatic differences between young longleaf-pine silvopasture and open-pasture

Abstract

Information is needed relative to changes that occur in microclimatic conditions in the early stages of open-pasture to pine silvopasture conversion in the Southeastern USA. This research tested the hypothesis that microclimatic conditions would vary between young-pine silvopasture and open-pasture. The research was conducted in a longleaf-pine (Pinus palustris Mill.)-bahiagrass (Paspalum notatum Flugge) silvopasture and adjacent open bahiagrass pasture at Americus, Georgia. Longleaf-pine was planted in the bahiagrass pasture in December 2000; the trees were not pruned or thinned until the study was completed. Microclimatic parameters (air temperature, soil temperature at 5 and 10 cm, wind speed, gust speed, wind direction, humidity, dew point, rainfall, soil-moisture content, total solar radiation, and photosynthetically active radiation) were collected from November 2005 to October 2008 using HOBO Ó weather stations located in each pasture type. Data were analyzed to determine overall, as well as seasonal, monthly, and diurnal differences between pasture types. Evapotranspiration was calculated from air temperature, wind speed, relative humidity, and total solar radiation. With the exception of rainfall, overall average values for all microclimatic parameters were different between pasture types. Silvopasture had higher overall average values for air temperature, soil temperature at both depths, and soil water content, but lower values for all remaining microclimatic parameters. Seasonal, monthly, and diurnal differences between pasture types were also detected for several parameters. The results suggested that water loss can be significantly reduced in the early stages of open-pasture to longleaf-pine silvopasture conversion in the Southeastern USA.

Resistance and resilience of root fungal communities to water limitation in a temperate agroecosystem

“…Given that trees in an agricultural system provide modifications to air temperature, water vapor content, relative humidity, PAR, and wind velocity (Jose, Gillespie, & Pallardy, 2004;Karki & Goodman, 2013), and stimulate higher biodiversity in both above-and belowground flora and fauna (Bainard et al, 2012;De Beenhouwer, Aerts, & Honnay, 2013), we expected the agroforestry systems to contribute to resistance and resilience of AMF to water limitation. While it has been shown that trees and crops can harbor the same species of AMF (Ingelby, Wilson, Munro, & Cavers, 2007), further research is needed to assess to the role of trees in maintaining AMF and other beneficial F I G U R E 5 Nonmetric multidimensional scaling (NMDS) ordinations for fungal communities in an agroforest (panels a and b) and monoculture (panels c and d).…”

Hair Cortisol as a Measure of Chronic Stress in Ewes Grazing Either Hardwood Silvopastures or Open Pastures

“…Microclimatic measures (ambient temperature, relative humidity, soil moisture, and PAR) indicate environmental conditions in OP were more stressful than in silvopasture treatments. Ambient temperature and PAR tend to be lower under tree canopies compared with open systems [31], and past studies have reported cooler microclimatic conditions in silvopasture versus OP [3,4,32,33]. The BSP and HSP silvopasture systems used in this study provided shade and lowered the PAR and ambient temperature within the system compared with OPs with no canopy cover.…”

Modelling Agroforestry’s Contributions to People—A Review of Available Models

“…For example, agroforestry can reduce the net loss in long-wave radiation from plant surfaces and protect plants from radiation frosts locally [32], alleviate drought stress of the crop [33,34], and alter the temperature, with positive and negative effects on the crop depending on the growth stage [33]. Agroforestry can further alter surface roughness and thus airflows [35], with potential effects on plant productivity through the reduction of wind speed [33,36], and reduce evapotranspiration of the crop [37] with potential effects of the tree age [38].…”