NPP Grassland: Badkhyz, Turkmenistan, 1948-1982

Summary:

Climate data for this site are also available: see Any Other Relevant Information in section 11 of this document.

More information on the entire Net Primary Production Project can be found at the NPP homepage.

Table of Contents

1. Data Set Overview
   
2. Investigator(s)
   
3. Theory of Measurements
   
4. Equipment
   
5. Data Acquisition Methods
   
6. Observations
   
7. Data Description
   
8. Data Organization
   
9. Data Manipulations
   
10. Errors
    
11. Notes
    
12. Application of the Data Set
    
13. Future Modifications and Plans
    
14. Software
    
15. Data Access
    
16. Output Products and Availability
    
17. References
    
18. Glossary of Terms
    
19. List of Acronyms
    
20. Document Information
    

1. Data Set Overview:

Data Set Identification:

Introduction:

Long-term observations on climate, soils and productivity of this ecosystem have been published by Nechaeva et al. (1971), Artykov (1975), and Kamelin and Rodin (1989).

Objective/Purpose:

Summary of Parameters:

1. Site

2. Treatment

3. Year

4. Month

5. Day

6. Date in decimal year

7. Above ground biomass

Discussion:

Related Data Sets:

2. Investigator(s):

Investigator(s) Name and Title:

Title of Investigation:

Contact Information:

c/o Department of Biology and Microbiology
South Dakota State University
Brookings, SD 57007
U.S.A.

Telephone (U.S.A.): +1 (605) 688-4925/6141
Fax (Russia): +7 (095) 200-2216/2217 (Attn. Gilmanov 002840)
Fax (U.S.A.): +1 (605) 688-6677
Email: Tagir_Gilmanov@sdstate.edu

3. Theory of Measurements:

Peak above-ground live biomass (or in some cases, the difference between maximum and minimum biomass) has been used as an estimate of net primary production - usually where only one or two measurements per year are available. Sometimes a conversion factor has been applied to take account of estimated turnover and the estimated ratio of above-ground to below-ground dry matter.

The "IBP Standard Method" of Milner and Hughes (1968) assumes that where live biomass increases between successive samples, production equals this increase; where biomass decreases or remains the same, production is assumed to be zero. Annual production is then obtained by summing the estimates for each sample interval.

Essentially, this method was used for the IBP synthesis by Singh and Joshi (1979), in particular for their estimates of below-ground production. A modified method was used for above-ground production, determined by a decision matrix (Singh et al., 1975); where increments in live biomass coincided with increases in standing dead matter, the latter were added to the monthly production.

The limitations of the above methods are discussed in detail by Long et al. (1989). In particular, the peak biomass method and variations on the IBP method underestimate production by not accounting for simultaneous growth and death. This may be significant in temperate grasslands with a long growing season, and is particularly a problem in tropical grasslands where the growing season may extend over much of the year. Some limited overestimation may occur by not accounting for periods of negative NPP (due to stress, or translocation between above and below ground plant parts) but underestimation of root turnover is probably the largest source of error. Long et al. (1989) estimated NPP for three terrestrial tropical grassland sites by summing monthly changes in live biomass plus losses due to death and decomposition for above and below ground vegetation. Monthly losses were determined as the change in dead matter plus the estimated disappearance of dead matter through decomposition. Dead matter disappearance was calculated each month as the product of relative decomposition rate and mean amount of dead matter.

Although some correlation between estimates obtained using different methods has been reported (Singh et al., 1975), the degree of underestimation may be strongly site-specific (Linthurst and Reimold, 1978; Long and Mason, 1983). Where sufficient data are available for a given grassland site, it may be possible to estimate NPP according to the different methods for the purposes of comparison. This may involve entry of data into algorithms or a spreadsheet containing these algorithms.

Methodological aspects of field experimental studies of biomass and production of grassland ecosystems in the Commonwealth of Independent States (former USSR) were summarized by Titlyanova (1988). The methods of field measurements of above-ground and below-ground biomass in Russian grasslands are based on the harvest technique and with respect to sampling area, replication, etc., are very close to the methods used by western ecologists during the IBP studies (e.g. Milner and Hughes, 1968; Sims and Coupland, 1979). The Russian approach to estimation of the annual production of grassland plant communities (with subdivision on aboveground and belowground components) is based on a calculation procedure utilizing data of repeated (usually 2-weekly) sampling during the season of live, standing dead and litter fractions of phytomass. This method of calculation gives the estimates of production which are 1.6 to 2.0 times higher than the seasonal maximum of the standing crop of the corresponding phytomass fraction (Titlyanova, 1988).

4. Equipment:

Sensor/Instrument Description:

• laboratory balance
• quadrat sampling frame

Collection Environment:

Platform/Source:

Platform/Source Mission Objectives:

Key Variables:

Principles of Operation:

Sensor/Instrument Measurement Geometry:

Manufacturer of Sensor/Instrument:

Calibration:

5. Data Acquisition Methods:

6. Observations:

Data/Field Notes:

site elevation (m): 700

mean annual precipitation (mm): 266

mean monthly min temperature (C): -14.7 (Jan)

mean monthly maximum temperature (C): 41.2 (July)

vegetation type: desert steppe

dominant species: Poa bulbosa (C3? photosynthetic types)

historical long-term management regime (estimated): NOT KNOWN

maximum aboveground live biomass (typical month): 69 g/m2 (May)

soil type: serozem, light loam

soil pH: 8.0

soil texture (sand/silt/clay): 0.68/ 0.23/ 0.15

soil carbon content: 1160 g/m2 (0-20 cm)

soil nitrogen content: 140 g/m2 (0-20 cm)

7. Data Description:

Spatial Characteristics:

Spatial Coverage:

Spatial Coverage Map:

Spatial Resolution:

Projection:

Grid Description:

Temporal Characteristics:

Temporal Coverage:

Temporal Coverage Map:

Temporal Resolution:

Data Description:

1.
variable=Site
definition=site where data were gathered
code=bdk: Badkhyz

2.
variable=Treatmt
definition=long term management of site
code=lngtrm: data not available

3.
variable=Year
definition=year in which data were collected
units=year
minimum=1948
maximum=1982

4.
variable=Mn
definition=month in which data were collected
units=month
minimum=01
maximum=05

5.
variable=Dy
definition=day in which data were collected
units=day
minimum=01
maximum=15

6.
variable=Tyear
definition=Date in decimal year
units=year plus the Julian date divided by 365
minimum=1948.041
maximum=1982.332

7.
variable=AGbiomass
definition=above ground biomass
units=[g][m^-2]
minimum=0
maximum=172

Sample Data Record:

Site   Treatmt   Year   Mn   Dy   Tyear     AGbiomass
------------------------------------------------------
bdk     lngtrm   1948   01   15   1948.041  5.0

8. Data Organization:

Data Granularity:

1. Data File bdk_npp.txt 4.7 KBytes
Period: 01 Jan 1948 through 01 May 1982
Latitude: 35.68N, Longitude: 62E

A general description of data granularity as it applies to the IMS appears in the EOSDIS Glossary.

Data Format:

Site;Treatmt;Year;Mn;Dy;Tyear;AGbiomass [units g/m2]

bdk;lngtrm  ;1948;01;15;1948.041;   5.0
bdk;lngtrm  ;1948;02;15;1948.126;   7.0

9. Data Manipulations:

Formulae:

Derivation Techniques and Algorithms:

Data Processing Sequence:

Calculations

Graphs and Plots

10. Errors:

11. Notes:

Limitations of the Data:

Known Problems with the Data:

Usage Guidance:

12. Application of the Data Set:

13. Future Modifications and Plans:

14. Software:

Software Description:

Software Access:

15. Data Access:

Contact Information:

Telephone: +1 (865) 241-3952
Email Address: ornldaac@ornl.gov

Data Center Identification:

Telephone: +1 (865) 241-3952
Email Address: ornldaac@ornl.gov

Procedures for Obtaining Data:

Data Center Status/Plans:

16. Output Products and Availability:

17. References:

Gilmanov, T.G., W.J. Parton and D.S. Ojima (1996) Testing the CENTURY ecosystem level model on data sets from eight grassland sites in the former USSR representing a wide climatic/soil gradient. Ecological Applications (in press).

Kamelin R.V. and L.E. Rodin, eds. (1989) Pistacea woodlands of Badkhyz. (In Russian). Nauka, Leningrad. 246 pp.

Linthurst, R. and R.J. Reimold (1978) An evaluation of methods for estimating the net primary production of estuarine angiosperms. J. Applied Ecology 15, 919-932.

Long, S.P. and Mason, C.F. (1983) Saltmarsh Ecology. Blackie, Glasgow.

Long, S.P., E. Garcia Moya, S.K. Imbamba, A. Kamnalrut, M.T.F. Piedade, J.M.O. Scurlock, Y.K. Shen and D.O. Hall (1989) Primary productivity of natural grass ecosystems of the tropics: a reappraisal. Plant and Soil 115, 155-166.

Milner, C. and R.E. Hughes (1968) Methods for the Measurement of the Primary Production of Grassland. IBP Handbook No.6. Blackwell, Oxford.

Nechaeva N.T., S.Ya. Prikhod'ko and K.F. Shuravin (1971) Harvest formation on the Poa-Carex pastures of the foothills of Central Asia in relation to meteorological conditions (as exemplified by Badkhyz, Turkmenian Republic). In: Biokompleksy pustyn' i povyshenie ikh produktivnosti. Ylym, Ashkhabad. p. 71-113. (In Russian).

Nechaeva, N. T., S. Ya Prikhod'ko, and K. F. Shuravin. 1971. Net Primary Production for Badkhyz (Turkmenistan) Grassland Site Dataset, In Nechaeva N.T., S.Ya. Prikhod'ko and K.F. Shuravin (1971) Harvest formation on the Poa-Carex pastures of the foothills of Central Asia in relation to meteorological conditions (as exemplified by Badkhyz, Turkmenian Republic). In: Biokompleksy pustyn' i povyshenie ikh produktivnosti. Ylym, Ashkhabad. p. 71-113. (In Russian).

Sims, P.L. and R.T. Coupland (1979) Producers. In: Grassland ecosystems of the world: analysis of grassland and their uses (ed. R.T. Coupland). Cambridge University Press. pp. 49-72.

Singh, J.S. and M.C. Joshi (1979) Tropical grasslands primary production. IN: Grassland Ecosystems of the World (R.T. Coupland, ed.) Cambridge University Press. pp. 197-218.

Singh, J.S., W.K. Lauenroth and R.K. Sernhorst (1975) Review and assessment of various techniques for estimating net aerial primary production in grasslands from harvest data. Botanical Review 41, 181-232.

Titlyanova, A.A. (1988) Methodology and methods of studying of the production-destruction processes in herbaceous ecosystems, In: Biologicheskaya produktivnost' travyanykh ecosistem [Biological productivity of herbaceous ecosystems] (V.B. Ilyin, ed.). Nauka, Novosibirsk (In Russian). pp. 3-10.

18. Glossary of Terms

A glossary of EOSDIS terms is available at http://www-v0ims.gsfc.nasa.gov/v0ims/glossary.of.terms.html.

19. List of Acronyms:

The EOSDIS Acronym and Abbreviation List is located at http://www-v0ims.gsfc.nasa.gov/v0ims/acronyms.html

20. Document Information:

Document Revision Date:

Review Date:

Document ID:

Citation:

Document Curator:

Document Author:

Document URL: