Changes in accumulation of organic matter and stable carbon and nitrogen isotopes in sediments of two Slovenian mountain lakes (Lake Ledvica and Lake Planina), induced by eutrophication changes

被引:68
作者
Vreca, Polona
Muri, Gregor
机构
[1] Jozef Stefan Inst, SI-1000 Ljubljana, Slovenia
[2] Natl Inst Biol, SI-1000 Ljubljana, Slovenia
关键词
D O I
10.4319/lo.2006.51.1_part_2.0781
中图分类号
Q [生物科学];
学科分类号
07 ; 0710 ; 09 ;
摘要
We measured accumulation rates of organic carbon (OC) and total nitrogen (TN) and stable carbon (delta C-13(org)) and nitrogen isotopes (delta N-15) in the sediments of two mountain lakes (Lake Ledvica and Lake Planina, northwest Slovenia). Marked variations of these parameters were observed in both sediments. OC accumulation rates ranged from 4 to 23 g m(-2) yr(-1) in Lake Ledvica, whereas in Lake Planina they were one order of magnitude higher and increased substantially in the upper sediments. delta C-13(org) and delta N-15 decreased upward in Lake Ledvica, from -25.5 parts per thousand to -28.4 parts per thousand, and from +2.1 parts per thousand to -3.4 parts per thousand, respectively. In contrast, substantial variations in the delta C-13(org) profile, ranging from -30.9 parts per thousand to -37.4 parts per thousand, but a quite uniform delta N-15 profile of approximately +1.8 parts per thousand, was observed in Lake Planina. Elemental and isotopic changes of bulk sedimentary organic matter in the lakes were related to changes in the past trophic state of the lakes and their watersheds, inferred by natural development of the lake ecosystems, anthropogenic activities, as well as earthquakes and forest fires. Observed changes and differences in the delta C-13(org) and delta N-15 records could be attributed to global changes in isotopic composition of atmospheric CO2 and nitrate in atmospheric deposition, as well as to differences in organic matter, dissolved inorganic carbon, and dissolved inorganic nitrogen sources at various altitudes. Although Lakes Ledvica and Planina are remote mountain lakes, the sediment records showed severe eutrophication in Lake Planina, whereas in Lake Ledvica eutrophication is still moderate, thus reflecting a high sensitivity of these ecosystems to any external inputs.
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页码:781 / 790
页数:10
相关论文
共 37 条
[1]   THE ASSESSMENT OF PB-210 DATA FROM SITES WITH VARYING SEDIMENT ACCUMULATION RATES [J].
APPLEBY, PG ;
OLDFIELD, F .
HYDROBIOLOGIA, 1983, 103 (JUL) :29-35
[2]  
APPLEBY PG, 2000, J LIMNOL S1, V59, P1
[3]   Climate variability and ecosystem dynamics of emote alpine and arctic lakes: the MOLAR project [J].
Battarbee, RW ;
Thompson, R ;
Catalan, J ;
Grytnes, JA ;
Birks, HJB .
JOURNAL OF PALEOLIMNOLOGY, 2002, 28 (01) :1-6
[4]   Lake Jezero v Ledvici ( NW Slovenia) - changes in sediment records over the last two centuries [J].
Brancelj, A ;
Sisko, M ;
Muri, G ;
Appleby, P ;
Lami, A ;
Shilland, E ;
Rose, NL ;
Kamenik, C ;
Brooks, SJ ;
Dearing, JA .
JOURNAL OF PALEOLIMNOLOGY, 2002, 28 (01) :47-58
[5]  
Brancelj A, 2000, PERIOD BIOL, V102, P259
[6]  
Brancelj A, 2002, HIGH MOUNTAIN LAKES
[7]  
Brencic M, 1998, RMZ MATER GEOENVIRON, V45, P17
[8]   BRANCHED-CHAIN AND CYCLOPROPANOID ACIDS IN A RECENT SEDIMENT [J].
CRANWELL, PA .
CHEMICAL GEOLOGY, 1973, 11 (04) :307-313
[9]  
Deines P., 1980, Handbook of environmental isotope geochemistry, P329, DOI DOI 10.1016/B978-0-444-41780-0.50015-8
[10]  
Fogel M.L., 1993, Organic Geochemistry, P73, DOI [10.1007/978-1-4615-2890-6_3, DOI 10.1007/978-1-4615-2890-6_3]