Data set ID:
There are 3 sites for this study: Gravelly Ridges, Aeolian, and Dona Ana. Within each site,
there are 8 plots. The plots are 8x8 meters and have an 8x8 buffer zone on both sides of the
plot (up and down). There are four BSNE stands for each plot, 2 in each of the 2 buffer zones
(8 collectors per plot). Each stand contains 2 BSNE collectors with the collection opening at
10cm and 30cm height and an opening of 2 cm wide and 5 cm height. These BSNE collectors are in
a fixed position pointing into the direction of the prevailing wind, which corresponds to the
plot alignment. The collectors in the upwind buffer are facing away from the plot and the
collectors in the downwind buffer are facing into the plot. The idea is the upwind BSNEs
measure the amount of dust entering the plot, and the downwind BSNEs measure the amount of dust
moving off the plot. This provides a measure of the effectiveness of the plot obstructions to
wind blown dust. It is important the BSNEs are fixed in an orientation that points across the
full length of the plot.
field data sheets and lab data sheets
Methodology document: Conn_BSNE_Collection_Procedure.doc
Plot maps: Maps with the location of each stand within the plots are found in ConnectivityMicroplotMaps_A-D-G.pdf.
Connectivity BSNE Collection Procedure
Basic Set Up and Location
There are 3 sites for this study: Gravelly Ridges, Aeolian, and Dona Ana. Within each site, there are 8 plots. The plots are 8x8 meters and have an 8x8 buffer zone on both sides of the plot (up and down). There are four BSNE stands for each plot, 2 in each of the 2 buffer zones (8 collectors per plot). Each stand contains 2 collectors, 10cm and 30cm. These BSNEs are in a fixed position and all collectors should be pointing the same direction. The collectors in the upwind buffer are facing away from the plot and the collectors in the downwind buffer are facing into the plot. The idea is the upwind BSNEs measure the amount of dust entering the plot, and the downwind BSNEs measure the amount of dust moving off the plot. This provides a measure of the effectiveness of the plot obstructions to wind blown dust. It is important the BSNEs are fixed in an orientation that points across the full length of the plot. Maps of the location of each stand within the plots are found in ConnectivityMicroplotMaps_A-D-G.pdf.
1. The Connectivity BSNEs are collected quarterly in February, May, August, and November. They should be collected in the last week of the month and if not able, then the first week of the next month.
2. Use 6x4 inch, 4-mil Ziploc-style bags to collect samples. (When ordering bags, make sure you order 6x4 NOT 4x6 since the width is 6 inches and the length is 4 inches. Vender: National Bag Company, Inc., 800-247-6000, Part #90-760C6, 1000 bags/box)
3. The bags need to be preweighed before going to field. It is best to do this is as small of numbers as possible to get a better average. 10 at a time is appropriate.
4. Individual collection bags should be labeled as follows: Site (A, D, or G), Plot # (1-8), Stand # (1-4), and Height (10 or 30). So Aeolian site, Plot 3, Stand 1, 10 cm collector would be labeled: A3-1-10.
5. All bags from one site should be placed in a larger bag that is labeled with the site name, date collected, and the average bag weight.
NOTE: If you need to use multiple large bags to hold a particular site, make sure that all of the appropriate identifying information is on each of them. Write a set number on bags when multiple large bags are used; e.g., "1 of 2" if there are 2 large bags for All NPP. This will reduce chance of samples being misplaced.
1. To collect a sample, slide the cover off of the collector and put the narrow end of the collector inside the bag. Use a stencil brush to brush out all dust possible, paying close attention to dust caught on screws, behind the opening, and in corners. Remove most of the air and seal the bag shut. Shake out any debris above the screen, inspect the condition of the collector, slide the cover back on, and place the collector back on its fin.
2. Record collection dates and times and any sample or maintenance notes in the LTER V Connectivity Pilot Study LTER study #308, BSNE Sample Collection Book at time of collection. This is kept in the filing cabinet in office 211.
3. A "pinch" or about 0.10 g is minimum sample size to collect. If a collector has less than this, dump the sample out and do not collect it. Make a note on the datasheet that it was not collected and why. Collect all others that have the minimum sample size.
4. Do not collect samples out in the open if it is windy enough to blow some of the fine dust away, as this will bias the samples in the particle size analysis.
5. If a collector has water in it, do not collect the sample.
* Wait until the collector dries out naturally and collect it then.
* If one or more collectors are wet and others are dry, do not collect the dry collectors until the wet ones dry out.
* All collectors that will be compared with each other should be collected on the same day. (All collectors within a sampler and all samplers within a site should be collected at the same time.
* If many samplers at a site have wet collectors, postpone collection until they are all dry.
* If some have been collected before you realize that others are wet, use your best judgment as to whether the remainder of the site should be collected or postponed. (I.e., What will allow for the best comparison? If the majority were collected before the wet ones were discovered, finish the site, and collect the others as soon as possible.) Do NOT throw out samples that were already collected!
6. If samples are not collected on the expected date(s), a history log entry should be made explaining the delay so that Greg knows that he is not missing samples from the expected dates. The appropriate history log file can be found at connectivity.his.
7. If a collector is completely full with dust (i.e. potentially overflowing), it should be dumped in the field and not collected. A note should be made in the appropriate databook.
8. If there are spider webs inside or in the opening of the collector, remove the spider web and do not put it in the sample bag. Make a note in the data book and record whether part of the sample might have been lost (due to sticking to the web) and approximately how much. (For estimating amounts, don't use "a little" or "a lot." These are very subjective terms. A "pinch" or "half a teaspoon" or "~0.5 gram" are better qualitative answers.
9. If there is debris in the sample and the debris is easy to remove without removing sample along with it, do not include the debris in the sample. We are only interested in sand and soil, so leaves, insects, and twigs can be removed. However, if dust is stuck to the debris or the debris is too small to grab without grabbing dust too, collect the debris along with the sample.
10. If there is rust or paint flakes in the sample, collect the sample and make a note in the appropriate data book of the contamination and amount of contamination. These collectors should be replaced.
11. If there is white mineral crust on the inside of the collector, make a note of this, too. These collectors should be replaced and cleaned in the lab. Note: a white, airborne dust deposition has occurred in the past that is part of the dust sample and should be collected. A mineral crust is a metallic reaction and would need cleaning with LimeAway in the lab to remove it. This has not occurred for many years and the manufacturing process may have improved that alleviates the potential. Document its occurrence and notify John Anderson if this occurs.
12. When a collector is replaced, record in the databook when it was replaced and the reasoning of doing so.
13. It is very important not to stand or kneel in front of the BSNE collector opening. Stay behind or to the side of the collectors at all times to minimize soil disturbance in the prevailing wind direction. When it is necessary to walk near the samplers (i.e., during maintenance or collection) minimize disturbance by walking flatfooted and smoothing out any disturbances made.
1. Clip to ground level any vegetation growing immediately in front of the fixed collectors to allow unrestricted dust entrance. Avoid disturbing the ground in front of the collector.
2. The height of the collectors needs to be checked periodically, especially during windy periods or following overland water flow when scouring can remove soil from the ground surface below them. The height should be measured to the bottom of the opening of each collector to the ground.
3. To lower the height of the sampler as a whole, hammer down the sampler stem (center pipe on which the dust collectors are mounted). A tape measure should be kept in the "Icky Box" at all times. The angle of the sampler stem must also be checked, especially after height adjustments are made. The sampler stem should be vertical, parallel to the plane of gravity.
4. If the distance between the collectors has changed (as opposed to the whole sampler moving as a unit) or if sampler height must be increased, loosen the screw on the collars that the fins rest on. Move the fins to the appropriate height, and re-tighten the screws.
5. Any collector with excessive mineral crusts developing inside (caused by rainwater evaporation) should be brought back to the lab to be cleaned. A few drops of Lime-Away will dissolve the crust so it can be wiped out easily. The collector should be rinsed thoroughly when done; the samples may eventually be analyzed for mineral content and we don't want Lime-Away to be the primary constituent. Please note any excessive deposition in the data book at the time of collection and record that it was removed and why it was removed.
6. If a collector is rusted or has holes in it, it must be replaced.
Sample and Data Processing
1. The samples are brought back to the lab and individually weighed (plastic bag + sample).
a. Record data on Connectivity BSNE lab datasheets. Print these forms from Connectivity_BSNE_sample_weights_lab_datasheet.xls.
b. Weigh and record sample weight to 3 decimal places.
c. When weighing, make sure that no part of the sample bag is touching anything but the weigh pan it rests on. Do not let the bag touch the edge of the scale cover or body of scale; this will affect the weight.
d. It helps to tare a medium sized bolt to hold down the sample bag when it is folded in half on the scale. This keeps the bag from moving around and results in a more accurate weight. The weight will also stabilize more quickly if the bag is not changing shape during the weigh process.
2. Data entry
a. After weighing all samples, the weights need to be entered and error checked (verified) into Connectivity_BSNE_sample_weights.xls.
b. The field data from the databook also needs to be entered into this same spreadsheet.
3. After all data has been entered and error checked:
a. Dust samples will be retained and archived here at the Jornada (as of 11/16/2010).
i. Data file: Connectivity_BSNE_sample_weights.xls
ii. History file: Connectivity.his
4. When samples are moved to the archive storage location , make sure to log the samples into the Shipping Log, including date and sample sites. This documentation of when and where the samples went is important for tracking purposes.
There are 3 site locations: Aeolian, Dona Ana, Gravelly Ridges. The UTM coordinates
below are approximate, and based on the UAV photo coverage we have for each site.
Precise GPS coordinates are available.
Dona Ana. These are located north of Herrick's SD97C (Surface Disturbance) exclosure,
which is north of the Dona Ana exclosure, which is in the SW corner of JER Pasture 6..
DA1 334992.42476300000 3596630.43159000000
DA2 334992.42675400000 3596112.28705000000
DA3 335490.35961900000 3596112.30170000000
DA4 335490.36881400000 3596630.40896000000
Aeolian. These are located just east of the gas pipeline, near the scrape site.
AE1 334253.41442800000 3606226.21293000000
AE2 333263.17702400000 3606226.21887000000
AE3 333263.16474900000 3605411.37177000000
AE4 334253.40961100000 3605411.35650000000
Gravelly Ridges. These are located south of the SE corner of the Gravelly Ridges
exclosure, north of the road to NASA. All are outside of the exclosure.
GR1 350381.01412200000 3604795.02860000000
GR2 349883.09428900000 3604795.02926000000
GR3 349883.11877100000 3604276.88904000000
GR4 350381.05237400000 3604276.87003000000
quarterly from 2008 to 2010
annually 2011 to 2016