Becky A. Ball 2014-11-12 Moss nutrient plasticity and stoichiometry tabular digitial data McMurdo Dry Valleys LTER McMurdo Dry Valleys LTER 10.6073/pasta/7de39d6f2feec6b636d3e0988b50ebcf https://mcm.lternet.edu/content/moss-nutrient-plasticity-and-stoichiometry     The McMurdo Dry Valleys of Antarctica is one of the coldest and driest habitats on the planet. As vascular plants are absent in this region, moss is the main form of above-ground primary production with a potentially important contribution to biogeochemical cycling, yet little is known about their ecological role. To determine the relationship between moss and soil properties relevant to biogeochemistry, we sampled both from a variety of locations in the Dry Valleys. Moss presence was compared to soil properties, and we measured the plasticity of moss stoichiometry (C:N:P) across gradients in nutrient availability. Results demonstrate that many soil properties significantly differed with moss presence, particularly conductivity and pH, but there is no strong evidence that this is caused by the  moss presence and not the conditions inherent to the microsites where moss was found. There is great variability in moss stoichiometry, with some significant differences between sites, but generally variability within sites is larger than variation among sites. Results suggest that the main source of moss nutrients is from the soil, rather than water, but correlations with any one nutrient source are weak, suggesting a great deal of plasticity in moss stoichiometry and nutrient uptake.        Related Publication citation: Ball, B. and R. Virginia. 2014. The ecological role of moss in a polar desert: implications for aboveground-belowground and terrestrial-aquatic linkages. Polar Biology 37:651-664.      Notes about the attribute table SITE Codes: In the attribute table, the site is the 3-letter code for the location of the moss and soil sample. The actual lat/lon point coordinates can be retrieved from the map at http://mcmlter.org/moss_samples_map.For MossNutrientData.csv, the sites are: AIK Aiken Creek 77.6013-77.6022 163.2772-163.299AND Anderson Creek 77.623 162.9071BOH Bohner Creek 77.6962 162.5573CAN Canada GlacierASPA 77.607-77.6131 162.9955-163.0915CPCR Cape Crozier 77.4568 169.2001CPRO Cape Royds 77.5411 166.174-164.1742CRES Crescent Stream 77.6195-77.62 163.1837-163.1845DEL Delta Stream 77.6249-77.65136111 163.104944444444-163.1374722GAR Garwood Valley 78.0171666666667-78.0238 163.9256-164.0430278RN Green Creek 77.6228-77.6243 163.0563-163.0654HARN Harnish Creek 77.6089-77.6139 163.2355-163.2532HUEY Huey Creek 77.5972-77.6045 163.1045-163.125LB Lake Bonney (south shore) 77.7245-77.7302 162.2879-162.3151LKCHD Lake Chad (south shore) 77.653 162.7047LF Lake Fryxell (south shore) 77.5996-77.6551 163.125-163.2645LH Lake Hoare (north shore) 77.6245-77.6246 162.8891-162.8913LSC Lost Seal Creek 77.5917-77.5947 163.2466-163.2586LYONS Lyons Stream 77.7281 162.2803MCK McKnight Creek 77.5993-77.5594 163.2659-163.2669OBH Observation Hill 77.85 166.68PRISC Priscu Stream 77.7124-77.7128 162.576-162.5935SNOW Snow Patch north of Lake Fryxell 77.6004 163.102VONG Von Guerard Stream 77.6104-77.6188 163.2553-163.2835WHAR Wharton Creek 77.6451 162.7447For SoilTransectData.csv, the sites are: SP1 Snow Patch 1SP2 Snow Patch 2SP3 Snow Patch 3SP4 Snow Patch 4SP5 Snow Patch 5CS1 Canada Stream 1CS3 Canada Stream 3DS Delta StreamGV Garwood ValleyVG Von Guerard StreamHC1 Huey Creek 1HC2 Huey Creek 2GC Green Creek LS Lost Seal StreamMC McKnight CreekPreserved Samples Preserved samples are stored in R. Virginia's lab at Dartmouth College and B. Ball's lab at Arizona State University at the West Campus. 2007-12-01 2011-01-31 ground condition As needed [term:vocabulary] None <cntorg>McMurdo Dry Valleys LTER</cntorg> <onlink>http://mcmlter.org/</onlink> <span property="dc:title" content="McMurdo Dry Valleys LTER" class="rdf-meta element-hidden"></span> Name: Ross A. Virginia Role: associated researcher Name: Inigo San Gil Role: data manager Not Applicable Not Applicable Field and/or Lab Methods Stream and snow patch transect sampling: At 10 stream locations and 5 different snow patches, transect sampling was conducted to determine soil parameters under moss vs. without moss presence. At stream locations, three replicate parallel transects were sampled. Between four and six samples were taken along each transect: in the dry soil beyond the hyporheic margin (Position 1), in the wetted area of the hyporheic zone (Position 2), at the edge of the flow of water in the stream from beneath a moss patch (Position 3a) and a nearby location not below moss (Position 3b), and from the center of the stream beneath a moss patch (Position 4a) and a nearby location not below moss (Position 4b). Because streams differ in morphology (e.g. stream width and size of wetted hyporheic zone), the length of the transects differs with each stream, ranging from 5-33 m in total length, as does the distance between sampling positions. At snow patch locations, three replicate parallel transects were sampled downslope of the snow patch, running parallel to the base of the snow patch. Transect A was within 30 cm of the base of the snow patch, B was 1.5-2 m below A, and C was 2-3 m below B. Transects were each 10 m in length, with five evenly-spaced points sampled along each. Moss samples occur randomly among those sampling points, and no moss was found below snow patches 1 and 4. At each sampling position, a soil moisture probe was inserted into the soil to measure field levels of soil water content. Any existing moss was sampled using a clean plastic spoon and put into a clean bag. Below the moss, soil samples were taken at two depths (0-2 cm and 2-7 cm, approx. 500 g each) using a clean plastic scoop and placed in a separate sterile bag. Both moss and soil were transported to the laboratory in a cooler, where they were stored at 4°C until processing. Moss tissues and subsamples of soil were frozen at -20°C and shipped to the United States for nutrient analysis. A variety of soil properties were measured on each soil sample. First, soils were hand-sorted to remove particles larger than approx. 2 mm diameter (or sieved, when soils were dry enough). Gravimetric SWC was estimated by drying approximately 25 g of soil at 105°C for 24 hrs and calculated as the percentage of dry soil. Soil pH was measured using a 2:1 water:soil dilution with a standard pH electrode. Electrical conductivity (EC) was measured using an EC meter on a 5:1 DI water:soil dilution by weight and reported as µS/cm. Measurements were calibrated by measuring the conductivity of a standard solution of 0.01 M KCl and correcting values for the influence of solution temperature (Barrett et al. 2004). For measurements of extractable phosphate (PO4-P), 10 ± 0.5 g soil was extracted in 50 ml 0.5 M NaHCO3 at pH 8.5. Samples were filtered to remove soil, then 3 ml of 6 N HCl were added to each. Samples were allowed to degas prior to being frozen until run on a Lachat Autoanalyzer. For extractable inorganic N (NO3 + NO2-N and NH4-N), 20 ± 0.5 g soil was extracted in 50 ml 2 M KCl, filtered, then frozen until run on a Lachat Autoanalyzer. Total and inorganic C and N were measured on soils ground using a sapphire mortar and pestle that were either left unacidified or acidified with HCl respectively. Samples were analyzed on a Carlo Erba Elemental Analyzer. Moss stoichiometry sampling and processing: Moss was sampled from multiple locations within and near the McMurdo Dry Valleys over the course of several field seasons. Samples were found across the three lake basins of Taylor Valley, as well as at several other locations, including a nearby valley (Garwood Valley) and Ross Island (n ear McMurdo Station at Observation Hill, as well as adjacent too two of the penguin rookeries at Cape Royds and Cape Crozier). When moss turfs were located, a moss sample of approx. 3 cm in diameter was collected (to a depth that included the entire core of moss carpet, usually ~1 cm) using a clean plastic spoon and placed in a sterile whirl-pack bag. The soil immediately beneath the moss was collected at the same time to approximately 7 cm (~150 g) using a clean plastic scoop and placed in a separate sterile whirl-pack bag. Both moss and soil were transported to the laboratory in a cooler, where they were both stored at 4°C until processing. When possible, stream and groundwater samples were also taken. Stream samples were collected directly from the nearby streamflow by submerging a plastic syringe, then ejecting the water into a clean, acid-washed plastic bottle through a sterile 0.45 μm nylon syringe filter. Groundwater samples were taken using a mini piezometer comprised of perforated plastic tubing inserted into the ground below the moss using a hand-vacuum pump to remove water. The groundwater was collected in clean Nalgene bottles, then vacuum filtered into a new plastic bottles. Filtered water samples were frozen until analyzed in the Crary Laboratory at McMurdo Station. Inorganic N (NO3 + NO2-N and NH4-N) and P (PO4-P) were measured on a Lachat Autoanalyzer. Soil samples were analyzed for gravimetric SWC, mineral N and P, and total and organic C and N, as described in the previous section. Moss samples, including those from the transects, were measured for nutrient content. Given the amount of sedimentation, moss samples were washed free of as much soil as possible using tap water under a dissecting stereomicroscope. Moss samples were then dried at 60°C before being ground to a fine powder using a mortar and pestle. Total C and N were measured on a subsample of moss on an elemental analyzer. Total P, as well as other cations micronutrients (K, Ca, Na, Zn, Mg, Mn, and Fe), were measured using a dry ash acid digestion method in which a moss subsample was ashed in a muffle oven that was gradually brought to 475°C over 1.5 hours, held at 475°C for 4 hours, then dropped to 105°C until digested. Moss ash was then weighed for calculation of ash-free dry mass (AFDM), then digested in 5 ml of 35% HNO3. Samples were then centrifuged at 25250 x g for 10 min, and the supernatant diluted to 5% HNO3 for measurement using inductively coupled plasma optical emissions spectroscopy (ICP-OES). Stream and snow patch transect sampling: At 10 stream locations and 5 different snow patches, transect sampling was conducted to determine soil parameters under moss vs. without moss presence. At stream locations, three replicate parallel transects were sampled. Between four and six samples were taken along each transect: in the dry soil beyond the hyporheic margin (Position 1), in the wetted area of the hyporheic zone (Position 2), at the edge of the flow of water in the stream from beneath a moss patch (Position 3a) and a nearby location not below moss (Position 3b), and from the center of the stream beneath a moss patch (Position 4a) and a nearby location not below moss (Position 4b). Because streams differ in morphology (e.g. stream width and size of wetted hyporheic zone), the length of the transects differs with each stream, ranging from 5-33 m in total length, as does the distance between sampling positions. At snow patch locations, three replicate parallel transects were sampled downslope of the snow patch, running parallel to the base of the snow patch.Transect A was within 30 cm of the base of the snow patch, B was 1.5-2 m below A, and C was 2-3 m below B.Transects were each 10 m in length, with five evenly-spaced points sampled along each. Moss samples occur randomly among those sampling points, and no moss was found below snow patches 1 and 4. At each sampling position, a soil moisture probe was inserted into the soil to measure field levels of soil water content. Any existing moss was sampled using a clean plastic spoon and put into a clean bag. Below the moss, soil samples were taken at two depths (0-2 cm and 2-7 cm, approx. 500 g each) using a clean plastic scoop and placed in a separate sterile bag. Both moss and soil were transported to the laboratory in a cooler, where they were stored at 4°C until processing. Moss tissues and subsamples of soil were frozen at -20°C and shipped to the United States for nutrient analysis. A variety of soil properties were measured on each soil sample. First, soils were hand-sorted to remove particles larger than approx. 2 mm diameter (or sieved, when soils were dry enough). Gravimetric SWC was estimated by drying approximately 25 g of soil at 105°C for 24 hrs and calculated as the percentage of dry soil. Soil pH was measured using a 2:1 water:soil dilution with a standard pH electrode. Electrical conductivity (EC) was measured using an EC meter on a 5:1 DI water:soil dilution by weight and reported as µS/cm.Measurements were calibrated by measuring the conductivity of a standard solution of 0.01 M KCl and correcting values for the influence of solution temperature (Barrett et al. 2004). For measurements of extractable phosphate (PO4-P), 10 ± 0.5 g soil was extracted in 50 ml 0.5 M NaHCO3 at pH 8.5. Samples were filtered to remove soil, then 3 ml of 6 N HCl were added to each. Samples were allowed to degas prior to being frozen until run on a Lachat Autoanalyzer. For extractable inorganic N (NO3 + NO2-N and NH4-N), 20 ± 0.5 g soil was extracted in 50 ml 2 M KCl, filtered, then frozen until run on a Lachat Autoanalyzer. Total and inorganic C and N were measured on soils ground using a sapphire mortar and pestle that were either left unacidified or acidified with HCl respectively. Samples were analyzed on a Carlo Erba Elemental Analyzer.Moss stoichiometry sampling and processing: Moss was sampled from multiple locations within and near the McMurdo Dry Valleys over the course of several field seasons. Samples were found across the three lake basins of Taylor Valley, as well as at several other locations, including a nearby valley (Garwood Valley) and Ross Island (n ear McMurdo Station at Observation Hill, as well as adjacent too two of the penguin rookeries at Cape Royds and Cape Crozier). When moss turfs were located, a moss sample of approx. 3 cm in diameter was collected (to a depth that included the entire core of moss carpet, usually ~1 cm) using a clean plastic spoon and placed in a sterile whirl-pack bag. The soil immediately beneath the moss was collected at the same time to approximately 7 cm (~150 g) using a clean plastic scoop and placed in a separate sterile whirl-pack bag. Both moss and soil were transported to the laboratory in a cooler, where they were both stored at 4°C until processing. When possible, stream and groundwater samples were also taken. Stream samples were collected directly from the nearby streamflow by submerging a plastic syringe, then ejecting the water into a clean, acid-washed plastic bottle through a sterile 0.45 μm nylon syringe filter. Groundwater samples were taken using a mini piezometer comprised of perforated plastic tubing inserted into the ground below the moss using a hand-vacuum pump to remove water. The groundwater was collected in clean Nalgene bottles, then vacuum filtered into a new plastic bottles. Filtered water samples were frozen until analyzed in the Crary Laboratory at McMurdo Station.Inorganic N (NO3 + NO2-N and NH4-N) and P (PO4-P) were measured on a Lachat Autoanalyzer. Soil samples were analyzed for gravimetric SWC, mineral N and P, and total and organic C and N, as described in the previous section. Moss samples, including those from the transects, were measured for nutrient content. Given the amount of sedimentation, moss samples were washed free of as much soil as possible using tap water under a dissecting stereomicroscope. Moss samples were then dried at 60°C before being ground to a fine powder using a mortar and pestle.Total C and N were measured on a subsample of moss on an elemental analyzer. Total P, as well as other cations micronutrients (K, Ca, Na, Zn, Mg, Mn, and Fe), were measured using a dry ash acid digestion method in which a moss subsample was ashed in a muffle oven that was gradually brought to 475°C over 1.5 hours, held at 475°C for 4 hours, then dropped to 105°C until digested. Moss ash was then weighed for calculation of ash-free dry mass (AFDM), then digested in 5 ml of 35% HNO3. Samples were then centrifuged at 25250 x g for 10 min, and the supernatant diluted to 5% HNO3 for measurement using inductively coupled plasma optical emissions spectroscopy (ICP-OES). unknown MossNutrientData CSV file Moss Nutrients DATASET_CODE Unique identifier for the table in the MCM LTER database - SOILS_MOSS_NUTRIENTS The data provider Unique identifier for the table in the MCM LTER database - SOILS_MOSS_NUTRIENTS SITE The 3- or 4-letter code for the location of the moss sample The data provider AIK Aiken Creek The data provider AND Anderson Creek The data provider BOH Bohner Creek The data provider CAN Canada Glacier ASPA The data provider CPCR Cape Crozier The data provider CPRO Cape Royds The data provider CRES Crescent Stream The data provider DEL Delta Stream The data provider GAR Garwood Valley The data provider GRN Green Creek The data provider HARN Harnish Creek The data provider HUEY Huey Creek The data provider LB Lake Bonney (south shore) The data provider LKCHD Lake Chad (south shore) The data provider LF Lake Fryxell (south shore) The data provider LH Lake Hoare (north shore) The data provider LSC Lost Seal Creek The data provider LYONS Lyons Stream The data provider MCK McKnight Creek The data provider OBH Observation Hill The data provider PRISC Priscu Stream The data provider SNOW Snow Patch north of Lake Fryxell The data provider VONG Von Guerard Stream The data provider WHAR Wharton Creek The data provider LOCATION_NAME Name of the location were the sample was acquired The data provider Name of the location were the sample was acquired DATE_TIME The date (MM/DD/YY) the moss and soil samples were collected from the field The data provider calendar date/time MM/DD/YYYY gregorian calendar MossC Total carbon content of the moss - percent by weight The data provider percent MossN Total nitrogen content of the moss - percent by weight The data provider percent MossP Total phosphorous content of the moss - percent by weight The data provider percent SoilAmmo Extractable ammonia concentration in the soil - in micrograms per gram of soil The data provider microgramsPerGram SoilNitr Extractable nitrate concentration in the soil - in micrograms per gram of soil The data provider microgramsPerGram SoilPhos Extractable phosphate concentration in the soil - in micrograms per gram of soil The data provider microgramsPerGram SoilC Total carbon content of the unacidified soil -percent by weight The data provider percent SoilN Total nitrogen content of the unacidified soil -percent by weight The data provider percent SoilCorg Soil organic carbon content determined as the carbon content of acidified soil -percent by weight The data provider percent Swc The gravimetric soil water content -per unit weight % g/g The data provider percent GroundNitr Nitrate concentration in the groundwater - micrograms per Liter The data provider microgramsPerLiter GroundAmmo Ammonia concentration in the groundwater - micrograms per Liter The data provider microgramsPerLiter GroundPhos Phosphate concentration in the groundwater - micrograms per Liter The data provider microgramsPerLiter StreamNitr Nitrate concentration in the stream water - micrograms per Liter The data provider microgramsPerLiter StreamAmmo Ammonia concentration in the stream water - micrograms per Liter The data provider microgramsPerLiter StreamPhos Phosphate concentration in the groundwater - micrograms per Liter The data provider microgramsPerLiter McMurdo Dry Valleys LTER The data distributor shall not be liable for innacuracies in the content http 1 0 \r\n 1 column , https://mcm.lternet.edu/sites/default/files/MossNutrientData.csv None SoilTransectData CSV file for Soil Transects DATASET_CODE Unique identifier for the table in the MCM LTER database - SOILS_MOSS_NUTRIENTS The data provider Unique identifier for the table in the MCM LTER database - SOILS_MOSS_NUTRIENTS LOCATION_NAME Name of the location were the sample was acquired The data provider Name of the location were the sample was acquired SITE The 3- or 4-letter code for the location of the moss sample The data provider CS1 Canada Stream #1 The data provider CS3 Canada Stream #3 The data provider DS Delta Stream The data provider GV Garwood Valley The data provider GC Green Creek The data provider HC1 Huey Creek #1 The data provider HC2 Huey Creek #2 The data provider LS Lost Seal Stream The data provider MC McKnight Creek The data provider SP1 Snow Patch #1 The data provider SP2 Snow Patch #2 The data provider SP3 Snow Patch #3 The data provider SP4 Snow Patch #4 The data provider SP5 Snow Patch #5 The data provider VG Von Guerard Stream The data provider TRANSECT The letter representing the replicate transect at that site (A, B, or C) The data provider The letter representing the replicate transect at that site (A, B, or C) POSITION The number representing the position of the soil sample along the transect (1, 2, 3 or 3b, 4 or 4b) The data provider The number representing the position of the soil sample along the transect (1, 2, 3 or 3b, 4 or 4b) DEPTH The upper 0-2 cm soil sample (U) or lower 2-7 cm soil sample (L). The data provider U upper 0-2 cm soil sample The data provider L lower 2-7 cm soil sample The data provider MOSS Presence/Absence of moss in the sample The data provider Y Yes, there was moss present above that soil sample The data provider No No, there was no moss present and the soil sample did not come from under moss. The data provider DATE_TIME The date (MM/DD/YY) the moss and soil samples were collected from the field The data provider calendar date/time MM/DD/YYYY gregorian calendar NH4 Extractable ammonia concentration in the soil - in micrograms per gram of soil The data provider microgramsPerGram NO3 Extractable nitrate concentration in the soil - in micrograms per gram of soil The data provider microgramsPerGram PO4 Extractable phosphate concentration in the soil - in micrograms per gram of soil The data provider microgramsPerGram SoilC Total carbon content of the unacidified soil -percent by weight The data provider percent SoilN Total nitrogen content of the unacidified soil -percent by weight The data provider percent SoilCorg Soil organic carbon content determined as the carbon content of acidified soil -percent by weight The data provider percent pH The inverse of log of the hydrogen ion concentration of a 1:2 soil water paste - dimensionless number that may range from 0 to 14. The data provider dimensionless EC The electrical conductivity in microSiemens/cm of a 1:5 soil:deionized water solution. The data provider microSiemensPerCentimeter Swc The gravimetric soil water content -per unit weight % g/g The data provider percent Bmass The Microbial biomass carbon in micro grams of carbon per gram of soil The data provider microgramsPerGram McMurdo Dry Valleys LTER The data distributor shall not be liable for innacuracies in the content http 1 0 \r\n 1 column , https://mcm.lternet.edu/sites/default/files/SoilTransectData.csv None 2014-11-12 2014-11-12 McMurdo Dry Valleys LTER http://mcmlter.org/ Biological Data Profile of the Content Standards for Digital Geospatial Metadata devised by the Federal Geographic Data Committee. Drupal Ecological information Management Systems, version D7, Biological Data Profile module