A national scientific reference site network within the Terrestrial Ecosystem Research Network, site stratification and establishment methods

Transcription

1 A natinal scientific reference site netwrk within the Terrestrial Ecsystem Research Netwrk, site stratificatin and establishment methds Fulkes, J. N, White, I. A, and Lwe, A. J. Science Resurce Centre, Department fr Envirnment and Natural Resurces, Adelaide, Suth Australia Keywrds: bidiversity; rangelands; reference sites Abstract The Australian rangelands cver arund 80% f the cntinent yet, frm a bidiversity perspective, prbably cnstitutes the mst understudied part. T further the understanding f these ecsystems and prgress analytical and predictive mdelling, the Terrestrial Ecsystem Research Netwrk (TERN) thrugh a cllabratin between Adelaide University and the SA Department f Envirnment and Natural Resurces, is in the initial stages f a prcess t establish a Natinal Scientific Reference Site Netwrk (NSRSN) acrss the rangelands. This paper describes the TERN setup. Intrductin T further the understanding f these ecsystems and prgress analytical and predictive mdelling, the Terrestrial Ecsystem Research Netwrk (TERN), thrugh a cllabratin between Adelaide University and the SA Dept f Envirnment and Natural Resurces, is in the initial stages f a prcess t establish a Natinal Scientific Reference Site Netwrk (NSRSN) acrss the rangelands. (A reference site is defined as a benchmark area f land in best n ffer cnditin and characteristic f larger, significant areas acrss bth widely distributed and restricted ecsystems). Fulkes et al. (2010) 1 f 6

2 Establishing the NSRSN will present challenges, but will als prvide pprtunities t: imprve the knwledge and understanding f the dynamics f the mst extensive and prly understd Australian ecsystems, by prviding quantitative infrmatin n the causal relatinship between species and envirnmental variables; help prgress the predictive analysis f species and ecsystems under envirnmental stressrs, including climate change; prvide the first majr reginal estimate f sil and vegetatin carbn and nutrient stcks; prvide a systematic baseline f reference areas that allw; nging and future assessment f change in cnditin due t envirnmental and anthrpgenic stressrs, including drught, management and climate change, directing restratin utcmes fr large-scale develpment prjects and ffset schemes, and a natinal integratin f the extensive plt-based data undertaken by state and territry survey and mnitring effrts; significantly advance a new range f mnitring methds, including pht pint based assessment f ecsystem change, integratin and calibratin f remte sensing methds and new DNA-based assessment f phylgenetic diversity, bigegraphic structuring, cnnectivity and demgraphics. The challenges f establishing the TERN NSRSN are cnsiderable. Fundamental t the success f the NSRSN is the need t acknwledge the data that has been cllected ver decades acrss a variety f pastral mnitring prgrams and ther lng-term scientific assessments. Where valuable and apprpriate, this needs t be captured and used as an imprtant fundatin fr lcating sites fr the prpsed NSRSN and t direct mnitring methds. Supprting this will be effective relatinships with the current custdians f this data. Ntwithstanding these imprtant backgrund cnsideratins, the establishment challenges include: Fulkes et al. (2010) 2 f 6

3 develping a cnsistent mnitring methd based upn apprpriate eclgical cnceptual framewrks suitable fr the rangelands regin and extensin int ther regins; lcating and establishing reference sites based n a lgical stratificatin prcess t adequately represent the rangelands; cllecting eclgically representative, site-based, baseline data and samples Thrugh plt-based methds, the NSRSN will seek t (see Table 1): quantify the diversity and abundance f perennial vegetatin (trees, shrubs and grasses); assess the state, cnditin and structural cmplexity f vegetatin, including demgraphic parameters f size and age class; derive sil carbn and nutrient stck estimatins; establish and recrd pht pint infrmatin; assess cnditin and landscape functin parameters; recrd vegetatin parameters that assist remte sensing interpretatin (e.g. grund cver and leaf area index) cllect species vucher specimens fr taxnmic validatin, and cllect leaf and sil samples fr establishment f an assciated DNA bank and future assessment f bidiversity genetic parameters (including DNA barcding and ppulatin genetic prfiling) The mnitring and assessment prcedures will be flexible and adaptive t respnd t stchastic events characteristic f the rangelands. Methds used will be cnsistent acrss the rangelands, repeatable, quantifiable and suitable fr each brad vegetatin cmmunity being studied. Data cllectin will be based n permanently marked plts t facilitate relcatin and re-sampling. Up t 3,000 reference plts will be established, with 15 t 20 plts lcated within a 20 km 2 area cnstituting a reference site. All sites will have a minimum data cllectin set, but sme sites may be sampled mre intensively than thers. Plt dimensins (i.e. hundreds f metres) will facilitate direct linking with remte sensing data. Fulkes et al. (2010) 3 f 6

4 Measurements at the establishment phase will include phtgraphic descriptins and pint based measurements f substrate type, perennial vegetatin species (trees, shrubs and grasses) and vertical structure, t describe plant phrenlgy and cver (t calibrate remte sensing). Vegetatin measurements at each plt will ccur alng 3 x 300 m transects (75 m apart) and sils will be cllected frm a minimum f 4 lcatins within the plt, frm depths f 0-5 cm and 5-30 cm. Samples f sils and leaf material frm each plant species will be cllected fr further analyses. Fllwing calibratins, mid infrared spectrmetry will be used t analyse the cllected sils fr carbn, nutrients, catin exchange capacity, misture cntent, and DNA bar-cding f the leaf specimens will be used t assess bidiversity genetic parameters f the perennial plants and sil cryptgams. Rainfall timing and amunt will be recrded (a majr driver f rangelands systems). Cllected data will initially be used t benchmark bidiversity in the biregins f the rangelands. Cllabratin with ther mnitring grups will be encuraged t btain the mst cmplete inventries pssible f flra and fauna at significant sites, and t value-add t the permanent sites. The lcatin f reference sites will invlve negtiatin with State and Territry agencies that will be undertaking the surveys fr the prject. Cnsideratin will be given t lcatin f current reference sites and lcatin f prpsed survey and mnitring effrts f partner rganisatins (e.g. Bush Blitz). The lcatin f reference sites will then be determined using a hierarchical stratificatin prcess which includes: IBRA biregins; land type; and disturbance regime. Reference sites will be replicated within and acrss the abve levels. The TERN NSRSN will als ffer multiple use (nn-destructive) pprtunities and additinal benefits including prviding: the framewrk n which t base ther research cmpnents (e.g. fauna mnitring); bilgical references t guide attainable targets fr restratin prjects; sites where ther agencies can undertake mnitring using their jurisdictinal methds t develp benchmarks/cntrls which have previusly been beynd the lgistical and financial resurces f that jurisdictin; and pprtunities fr jint prjects within TERN, such as lcating additinal flux twers within a TERN Scientific Reference Site Netwrk site. Fulkes et al. (2010) 4 f 6

5 Table 1. Summary parameters, methds and applicatins relevant t the NSRSN Parameter Methdlgy Applicatin Bidiversity discvery - taxnmic ID - DNA barcding species knwledge Species distributin - presence/absence - plt based assessment species distributin mdelling (e.g. biclimatic envelpe predictin fr present/future) Demgraphic prfile Cnditin assessment Remte sensing grund parameters Sil resurces - sil crusts - micrbilgy - sil respiratin Climate/Misture - plt-based age prfile - pht pints - ppulatin genetic assessment f cnnectivity and diversity - demgraphic surrgates (e.g. dendrchrnlgy) - landscape functin analysis - plt/pht based - prductivity - plt-based assessment f grund cver (%, green fractin, nngreen fractin, bare grund), vegetatin structure categries (frb, grass, shrub, tree) and leaf area index, etc. - C, N, P, K assessment - DNA barcding/taxnmy - rainfall cllectin - sil misture/temperature prbes mdelling species dynamics, demgraphic prcesses change in cnditin, structure r invasive species cmpsitin ver time imprved remte sensing accuracy and validatin f derived prducts stcks and flws f sils and rle in arid ecsystems water cycling in rangelands Fulkes et al. (2010) 5 f 6

6 The NSRSN in the rangelands will frm the quantitative methdlgical framewrk fr the TERN integratin f plt-based ecsystem research in Australia. Being built n a sund cnceptual framewrk will facilitate the extensin f the NSRSN int mesic ecsystems thrugh partnership with ther survey effrts (state and federal, e.g. Bush Blitz). The advantage f such an extensin will be t allw the c-analysis f a range f histrical pltbased data using the quantitative base-line framewrk prvided by the NSRSN. Tempral mnitring can be added t the spatial cverage f the NSRSN by cmbinatin with the Lng Term Eclgical Research (LTER) site netwrk, and ther lng term mnitring sites. Fulkes, J.N., White, I.A. and Lwe, A.J. (2010). A natinal scientific site netwrk within the Terrestrial Ecsystem Research Netwrk, sit stratificatin and establishment methds. In: Prceedings f the 16 th Biennial Cnference f the Australian Rangeland Sciety, Burke (Eds D.J. Eldridge and C. Waters) (Australian Rangeland Sciety: Perth). Fulkes et al. (2010) 6 f 6