# Influence of coniferous tree invasion on forest meadow soil properties on Bunch Grass Ridge and Deer Creek near the Andrews Experimental Forest, 1998 ## Dataset - **Database Code:** SP016 - **Title:** Influence of coniferous tree invasion on forest meadow soil properties on Bunch Grass Ridge and Deer Creek near the Andrews Experimental Forest, 1998 - **Abstract:** Measurements were made along transects running from mountain meadows, into transition zones where trees were invading meadows and then into mature forest to determine if the invasion of high central Oregon Cascade Mountain meadows by the surrounding forest altered soil properties. Prior studies shown that meadow soil chemical and biological characteristic change when they are invaded by surrounding trees. For instance meadow litter has been shown to be enriched in nitrogen when compared with tree litter. In this study, differences in nitrogen pools and cycling were observed supporting the view that nitrogen is more available in meadow soils than in forests and that these differences change rapidly when tree invade mountain meadows. As trees invade meadows, ß-glucosidase activity is also rapidly reduced suggesting that qualitative changes are taking place in microbial populations as microorganisms adjust to changes in litter quality. High correlations between litter depth and most variables suggest that meadow litter may control other aspects of biogeochemical cycling; a relationship not observed in the transition zone or the mature forest. With one exception, the values observed in the transition zone were intermediate between those in meadows and those in forest soils. In most cases, the values found in this zone were closer to those found in mature forests than in meadow soils suggesting that when trees invade meadows, soil properties are rapidly shifted toward those found in forests. These rapid changes may alter soils so that they are more likely to support trees than grass. This may partially explain why, areas where trees had been cut after they became established as small islands within the meadow are rapidly recolonized by trees rather than grass. - **Keywords:** soil properties; disturbance; inorganic nutrients; meadows; Long-Term Ecological Research (LTER); disturbance; inorganic nutrients - **Temporal coverage:** 1998-01-07 to 1998-01-09 - **Principal Investigator:** Robert P. Griffiths ## Data Entities 1. SP01601 ## Entity 1: SP01601 ### Attribute list - **TRANSLOC** — numeric(1.000000), range 1.0000 48.0000, number Location of sample site along transect starting within og - **SITE_NO** — numeric(1.000000), range 53.0000 57.0000, number Site designator - **TYPECODE** — numeric(1.000000), range 1.0000 3.0000, number Type code: 1=grass; 2=transition; 3=old-growth - **HYSTER** — numeric(1.000000), range 0.0000 100.0000, percent Percentage of core containing mycorrhizal mats like those of the genus Hysterangium - **GAUT** — numeric(1.000000), range 0.0000 100.0000, percent Percentage of core containing mycorrhizal mats like those of the genus Gautieria - **LITTER** — numeric(1.000000), range 0.0000 20.0000, centimeters Litter depth - **MOIST** — numeric(0.100000), range 0.0000 110.0000, percent Percent moisture - **SOILTEMP** — numeric(0.100000), range 0.0000 30.0000, degrees Celsius Soil temperature measured with Licor - **AIRTEMP** — numeric(0.100000), range 0.0000 30.0000, degrees Celsius Air temperature measured with Licor - **LIGHT** — numeric(0.100000), range 0.0000 2000.0000, micromoles per square meter per second Amount of light measured with Licor - **SOM** — numeric(0.010000), range 10.0000 110.0000, percent Soil organic matter - **PH** — numeric(0.010000), range 4.0000 7.0000, pH units pH - **EXAMM** — numeric(0.010000), range 0.0000 3.0000, micromoles per gram Extractable ammonium (dry weight basis) - **MINN** — numeric(0.010000), range 0.0000 50.0000, micromoles per gram Mineralizable nitrogen (dry weight basis) - **DENIT** — numeric(0.100000), range 0.0000 100.0000, nanograms per gram per hour Denitrification potential (dry weight basis) - **B_GLUC** — numeric(0.001000), range 0.0000 1.0000, micromoles per gram per hour Beta-glucosidase activity (dry weight basis) - **LABRESP** — numeric(0.100000), range 0.0000 50.0000, micrograms per gram per hour Laboratory respiration rates (dry weight basis, as C) - **FLDRESP** — numeric(0.010000), range 0.0000 100.0000, grams per square meter per day Field respiration rates (dry weight basis) - **SIR_H2O** — numeric(0.010000), range -3.0000 10.0000, micrograms per gram per hour Substrate-induced respiration with only H2O; no substrate added (dry weight basis, as C) - **SIR_1NM** — numeric(0.010000), range -8.0000 10.0000, micrograms per gram per hour Substrate-induced respiration with 1 nm glucose added (dry weight basis, as C) - **SIR_1M** — numeric(0.010000), range -9.0000 20.0000, micrograms per gram per hour Substrate-induced respiration with 1 m glucose added (dry weight basis, as C ) ## Attribute Definitions **AIRTEMP** Air temperature measured with Licor **B_GLUC** Beta-glucosidase activity (dry weight basis) **DENIT** Denitrification potential (dry weight basis) **EXAMM** Extractable ammonium (dry weight basis) **FLDRESP** Field respiration rates (dry weight basis) **GAUT** Percentage of core containing mycorrhizal mats like those of the genus Gautieria **HYSTER** Percentage of core containing mycorrhizal mats like those of the genus Hysterangium **LABRESP** Laboratory respiration rates (dry weight basis, as C) **LIGHT** Amount of light measured with Licor **LITTER** Litter depth **MINN** Mineralizable nitrogen (dry weight basis) **MOIST** Percent moisture **PH** pH **SIR_1M** Substrate-induced respiration with 1 m glucose added (dry weight basis, as C ) **SIR_1NM** Substrate-induced respiration with 1 nm glucose added (dry weight basis, as C) **SIR_H2O** Substrate-induced respiration with only H2O; no substrate added (dry weight basis, as C) **SITE_NO** Site designator **SOILTEMP** Soil temperature measured with Licor **SOM** Soil organic matter **TRANSLOC** Location of sample site along transect starting within og **TYPECODE** Type code: 1=grass; 2=transition; 3=old-growth