Změny sladkovodních ekosystémů v prostoru a čase Z8025 (učebna Z2, pondělí 14.00-15.50) 3. Změny vodních toků v podélném profilu GEOGRAFICKY USTAV PŘÍRODOVĚDECKÁ FAKULTA MU Mgr. Karel Brabec, Ph.D, brabec@sci.muni.cz SYLABUS 1. Úvod - teoretické koncepty 2. Prostorové škály říční krajiny 3. Změny vodních toků v podélném profilu 4. Laterální a vertikální interakce vodních toků s okolním prostředím 5. Stojaté vody - vztahy k povodí, procesy ve vazbě na prostorové členění 6. Dlouhodobé trendy ve vývoji vodních ekosystémů 7. Sezónní dynamika faktorů prostředí a biologických společenstev 8. Teplotní režim povrchových vod 9. Ekologické aspekty průtokového režimu a hydraulických podmínek 10. Antropogenní modifikace vodních ekosystémů (se zřetelem na časoprostorové aspekty) 11. Potenciální dopady změn klimatu ve sladkovodních ekosystémech 12. Časo-prostorové aspekty adaptačních opatření a revitalizací degradovaných ekosystémů 13. Případové studie PODÉLNÝ PROFIL TOKŮ ZONACE TOKŮ - toky energie - toky látek - biota - experimenty ukazující roli kouskovačů (odstranění hmyzu - role při rozkladu a transportu detritu) Small Streams shaded, zuol low n itrogen.high con nectivity to local riparian community; id others.., Mid lirrcl Slri*Jim%: ^^Sům*ihidifigrsůme Lonnectittty to riparian, ^^moderare nirrůgeri. Highly diverse. ^Munctionalfeeding groups ilrpcndance gf food webs, pfůdiiClian http://www.rivercontinuum.org/about.php TEORIE ŘÍČNÍHO KONTINUA - struktura a funkce říčních společenstev - predikovatelný průběh - geomorfologické a hydrologické změny - dynamická rovnováha River Continuum Concept (Vannote et al. 1980) PERIPHYTON VASCULAR HYDROPHYTE QĹ LU O O 4 LU to 5H < cc 6 f— 8-1 9 10 I I 12 ^PREDATORS 11........'MIHI RELATIVE CHANNEL WÍDTH Fig. 1. A proposed relationship between stream size and the progressive shift in structural and functional attributes of lotic communities. See text for fuller explanation. FLUVIAL ECOSYSTEMS changes of channel slope, shading, origin of organic matter, ratio of production and respiration, thermal regime, substrate characteristics River Continuum Concept (Vannote et al. 1980) ORGANICKÁ HMOTA - VELIKOST ČÁSTIC >LU Table 3.2 Nature and size categories of non-living particulate organic matter. (Modified from Cummins, 1974). Detritus Categories and Subcategories Coarse particulate organic matter (CPOM) Large woody debris Terrestrial leaves forming leaf packs Leaf, twig & bark fragments, needles, fruits, buds and flowers Plant and animal detritus, faeces Fine particulate organic matter {FROM} Ultrafine particulate organic matter (includ. microbes) Dissolved organic matter (DOM) Approximate Size Ranges >1 mm >64 mm >16to <64 mm >4to <16 mm >1 to < 4 mm >0.5 iim to <1 mm >0.45 (Jim to <75 |üliti <0.45 \xrr\ ORGANICKÁ HMOTA ■ ■ ® ŕ ' - ■ Soil organic matter Imports from upstream ecosystems Macrophytes Attached algae CPOM -7— Shredders Herbivores 1-,--1 Suspended algae .• • ů .\r: ■ Collector-gatherers Microbial production Macro-and micro-predators T~ I I X Microbial loop Exports to downstream ecosystems FIGURE 12.1 Simplified model of principal carbon fluxes in a stream ecosystem. Solid lines indicate dominant pathways of transport or metabolism of organic matter in a woodland stream. * denotes mineralization of organic carbon to carbon dioxide by respiration. See Figure 12.7 for a depiction of how energy inputs change with increasing river size. Note that storage is omitted. CPOM, coarse particulate organic matter; FPOM, fine paniculate organic matter; DOM, dissolved organic matter. (Modified from Wetzel, 1983.) MIKROBIÁLNI SMYČKA Ptiytoplankton (Primofy Production) GRAZING FOOD CHAIN Zooplankton Carbon D km ide Mb Phosphorus (CofnivOfŕsJ Fish " é Zooplankton — Microflagellcites MICROBIAL LOOP TEORIE ŘÍČNÍHO KONTINUA ZONACE TOKŮ i ' 2 ' 3 ' 4 ' 5 ' 6 ' 7 ' 8 ' 9 ' 10 ' II ' 12 ' STREAM ORDER Fig. 2. Hypothetical distribution of selected parameters through the river continuum from headwater seeps to a twelfth order river. Parameters include heterogeneity of soluble organic matter, maximum die! temperature pulse, total biotic diversity within the river channel, coarse to fine particulate organic matter ratio, and the gross photosynthesis/respiration ratio. limity TEORIE ŘÍČNÍHO KONTINUA - antropogenní vlivy (využití krajiny) - formulována pro povodí s listnatými lesy (mírné pásmo Severní Ameriky) - např. novozélandské toky - málo kouskovačů -nižší hranice lesa - malá retence CPOM -nepravidelné povodně - nezohledňuje vliv přítoků, jezer a dalších lokálních nebo regionálních faktorů (např. rozsáhlé záplavové území) • RELATIVE CHANNEL WIOTH Fig. 1, A proposed relationship between stream size and the progressive shift in structural and functional attributes of lotic communities. See text for fuller explanation. River Continuum Concept (Vannote et al. 1980) limity TEORIE ŘÍČNÍHO KONTINUA maximální diverzita je vázána na střední toky kde se vyskytuje největší variabilita abiotických podmínek (teplota) ale: diverzita ryb a planktónu je největší v tocích vyssino radu ale: v tropech mají největší teplotní variabilitu toky ' RELATIVE CHANNEL WIDTH Fig. 1. A proposed relationship between stream size and the progressive shift in structural and functional attributes of Iotic communities. See text for fuller explanation. nízkého řádu River Continuum Concept (Vannote et al. 1980) Questions and Comments on the River Continuum Concept (Statzner&Higler, 1985) limity TEORIE ŘÍČNÍHO KONTINUA předpoklad, že toky nízkého řádu jsou charakteristické velkým přísunem CPOM a mají vysoký podíl kouskovačů (shredders) - heterotrofní systém ale: mnohé říční systémy postrádají v pramenné oblasti lesy (např. suché a vysokohorské oblasti) ' RELATIVE CHANNEL WIDTH Fig. 1. A proposed relationship between stream size and the progressive shift in structural and functional attributes of lotic communities. See text for fuller explanation. River Continuum Concept (Vannote et al. 1980) Questions and Comments on the River Continuum Concept (Statzner&Higler,1985) obhajoba TEORIE ŘÍČNÍHO KONTINUA rozpory pocházejí z výzkumu zaměřeného na jednotlivé typy habitatů (kamenité peřeje) kvantita organismů vyjádřena biomasou (namísto relativní abundance) vyvolání diskuze, vznik dalších konceptů ' RELATIVE CHANNEL WIOTH Fig. 1. A proposed relationship between stream size and the progressive shift in structural and functional attributes of lotic communities. See text for fuller explanation. River Continuum Concept (Vannote et al. 1980) (Grubaugh et al., 1996) (Giller & Malmquist, 1998) stream zonation concept (ILLIES & BOTOSANEANU 1963) • crenal • rhithral • potamal Teorie spirálního koloběhu látek (Nutrient Spiralling Concept) Teorie spirálního koloběhu látek (Nutrient Spiralling Concept) Fig. 1.—Nutrient spiralling in a two-compartment stream. The spiralling length, S (m), is the sum of the uptake length, Sw (m), and the turnover length, SB (m). Fw (g s"1) is the downstream flux of dissolved nutrient in the water compartment, W, and FB (g s-1) is the downstream flux of nutrient in the particulate compartment, B. R and U (g m~2 s-1) are exchange rates of dissolved nutrient between the water compartment and a unit surface area of the particulate compartment. Nutrient Spiralling in Streams: Implications for Nutrient Limitation and Invertebrate Activity (Newbold et al., 1982) TEORIE OPAKOVANÉHO DISKONTINUA The serial discontinuity concept of lotic ecosystems - délka diskontinua (discontinuity distance)- posun parametru v rámci podélného profilu toku (pozitivní/negativní) vlivem regulace - intenzita - rozdíl v hodnotách parametru - vliv mají vlastnosti nádrže a její poloha na toku WARD, J. V., AND J. A. STANFORD. 1983. The serial discontinuity concept of lotic ecosystems, pp. 29-42 in T. D. Fontaine and S. M. Bartell (editors). Dynamics of lotic ecosystems. Ann Arbor Science Publishers, Ann Arbor, Michigan TEORIE OPAKOVANÉHO DISKONTINUA o 5 ís i- z m ■o CT E I T IM tbl [«] 1 Ä '/ v. if tf r/ t* ^ 1 ' * iii _ MT Ir Kí M j Li.LařT 1 1 1 in 1 t 1 11 L_L-aŕf 1 1 1 1 1 1 i 1 i.jaŕ'i 1 1 1 1 3 5 7 9 11 13 5 7 «11 1 9 1 7 S 11 Ihl STREAM OR D E R CC CL m N co to Q 'E >u O O 4-1 c Q. hifurt I, Relative change* in various parameters as a function ol stream order, based on our interpretation of natural *tream continua theory (solid lints I and postulated effect* (dashed lines) of damming head waters (left column), middle reaches (center column), urn) lower reaches (right column) of a riw system. Sec tm for luriher explanation. re % a Z 'J í re s i u E ut - UJ Ô > o O) re > o d) ■» — í3 .T . T > '/ I til tf n>, ! ÍF AS sŕ* V j*„____^s** 1a (U > "D O 4-1 C CD 3 E > D > > O O (X) 00 OJ ^ 2 _ j Figur« 2. Relative changes ui addntonal paramcicrs (see Fie,. I kgend), TEORIE OPAKOVANÉHO DISKONTINUA REGULATED RIVERS: RESEARCH Sc MANAGEMENT Regal. Rivers: Res. Mgrnt. 17: 303-310 (2001) DOl: 10.1002/rrr.659 ARENA REVISITING THE SERIAL DISCONTINUITY CONCEPT JACK A. STANFORD* * AND J.V. WARDb 1 Table L Regulated rivers where the serial discontinuity concept has been empirically evaluated with respect to responses to a suite of biophysical parameters, including flow, temperature and some measure of species distribution River (country1) Basin area Reach length Mode Discontinuity Distance Parameter References (km2) (km) orders (km) intensity Flathead (USA)* Upper 22 .H9 185 II + 1.5 + 30 Moderate (Stanford et a/., 1988) Lower 25 220 82 i: -1 >-82 Minor (Stanford et cti. 1988) Kootenai (USA) 27 250 7^ s + 1 + 75 Severe (Perry et tr/., 1986) Clearwater (USA) 24 960 225 II 1 1 + 40 Moderate (Mann and Brusven, 1991) Colorado (USA) Gunnison* 20 533 239 II + 2 + 80 Moderate (Ward and Stanford, 1991) Green 18 149 339 s + 2? 1 150 Severe (Stanford, 1994- Vinson, 2001) Grand Canyon 21........ 472 II NA >+472 Severe (Stevens et ai, 1997) Buffalo (South Africa) 1230 137 S, H NA + 0-30 Moderate (Palmer and O'Keefe, 1990) Caning (Australia) 804 0 L -1 -5 Moderate (Storey et a/., 1991) Tees (UK) NA 1 II + 0.5 Minor (Armitage and Blackburn, 1990) Ter (Spain) 3010 208* II + 1? + 32 Moderate (Sabater et ai. 1989) Loire (France) 117 000 1012* M n ii NA (Guinand et 1 9%) Mode refers to hypolimnial (H), epilimnial (E), or selective (S) release of wa ter from the dam(s). No n-regulated tributaries in every case significantly influenced discontinuities. * Entire length of river system included in study. TEORIE OPAKOVANÉHO DISKONTINUA n, W E Ľ CL Non-regulated Headwater Reach Regulated, Braided Mid-reach Regulated, Meandering Lower-Reach (partially reset) Figure ]. The theoretical framework of the SDC within a stream corridor from headwaters to mouth. Discontinuity distance (DD) is the downstream (positive) or upstream (negative) shift of a given parameter at a given distance (Jf, measured in steam orders or Euclidean distance) because of the regulation scheme. Parameter intensity (PI) is the strength (Y> which may also be positive or negative) of the regulation effect on biophysical parameter A. Interactive arrows that expand or contract show influences on longitudinal, lateral and vertical connectivity in direct relation to the position and mode of regulation (after Ward and Stanford, 1983a,b, 1995) Rhithron - podhorské potoky LAND DRAINAGE terrestrial Hynes, 1970: The Ecology of Running Waters Potamon - nížinné řeky LAND DRAINAGE terrestrial animals plant nutrients dissolved organic matter vegetable debris RWTHRON plant nutrients detritus and drift Ipiscňorous fishes |*V- TIT isgg$ plant nutrients dissolved 4 organic matter 4 drift detritus DOWN STREAM Hynes, 1970: The Ecology of Running Waters _»-~l*r- t> y. P m Morava Seasonal dynamics of chironomids in impounded river: taxa composition and life cycles Department of Geography Faculty of Science Masaryk University Karel Brabec, Ph.D, brabec@sci.muni.cz STUDY AIMS Effects of dams • disruption of river continuum • altered discharge and thermal regimes • sedimentation regime (transparency) • nutrients Study aims • to analyze chironomid response to altered conditions below dams • to apply both seasonaly sumarised characteristics and seasonal pattern CHIRONOMIDS AS INDICATORS • thermal preference/plasticity • feeding strategies and hydraulic preferences • growth, voltinism, seasonal dynamics of instars abundances • taxonomie structure of community/taxocoenoses • trait-based characteristics • life-cycle (instar composition, morphometric characteristics) STUDY AREA METHODS Biota • single habitat type - riffle in central part of river channel • 7 sites x 12 montly dates in 1992 • net with mesh 500 |im, sampling area 25x25 cm, • sorting in laboratory (stereomicroscope) • measurements of head length (in some cases also head width and body length were obtained) • identification (taxa + instar), linking to ecological traits Environmental characteristics • temperature and flow regime from 4 gauging stations (located close to LI, L3, L6 and L7) THERMAL REGIME sampling site LI L2 L3 L4 L5 L6 L7 distance from the source 49.7 59.9 65.1 76.4 92.9 103.1 128.5 distance from Vir Reservoir I (km) -1.0 0.9 6.1 17.4 33.9 44.1 69.5 altitude 467.0 395.0 361.0 324.5 257.7 235.0 194.0 channel width (m) 20.0 19.0 27.0 20.0 19.0 14.5 27.0 slope at site (%o) 2.30 7.50 5.70 2.75 2.85 1.60 1.00 conductivity (uS.cm-1) 180 190 211 238 265 303 324 pH 7.69 7.65 7.79 7.76 7.93 7.75 7.87 mean annual water temperature (°C) 7.70 7.33 7.36 7.41 7.78 8.18 9.41 degree days 2783 2628 2602 2687 2833 2904 3647 mean annual discharge (m3.s_1) 3.319 - 3.741 - - 7.808 7.114 mean diurnal range of water level (cm) 6 - 26 - - 18 36 temporal percentage of temperature exceeded □ > 1 °C □> 2 °C □> 3 °C □ >4°C D>5°C D>7°C □ >10°C ■>15°C ■>20°C 100 L6 90 80 70 60 50 40 30 20 10 j f m a m j j a s o n : o c OG II 111 111 lil f 1111 111 111 j I 1J m 1 1 i i m 11 16/28/yyyy 16/24/yyyy 16/20/yyyy |6/16/yyyy I6/12/yyyy 16/8/yyyy 16/4/yyyy 15/31/yyyy 15/27/yyyy 15/23/yyyy 15/19/yyyy 15/15/yyyy 15/11 /yyyy 15/7/yyyy 15/3/yyyy 14/29/yyyy 14/25/yyyy 14/21/yyyy 14/17/yyyy 14/13/yyyy 14/9/yyyy 14/5/yyyy í 4/1 /yyyy 111 111 111 1 j I 9/27/yyyy lg/23/yyyy 9/19/yyyy 9/15/yyyy 9/11/yyyy 9/7/yyyy 9/3/yyyy 8/30/yyyy 8/26/yyyy 8/22/yyyy 8/18/yyyy 8/14/yyyy 8/10/yyyy 8/6/yyyy 8/2/yyyy 7/29/yyyy 7/25/yyyy 7/21/yyyy 7/17/yyyy 7/13/yyyy 7/9/yyyy 7/5/yyyy 7/1/yyyy > i > X 11 111 111 Iff f X I X 71 1092 5439999999999^ FLOW REGIME 30.00 25.00 20.00 15.00 10.00 5.00 0.00 [ Jd 1 1 I u 1 MIß. 1 i i r 1 \ KM -qLl -qL3 • LI samplings 16-Dec-94 16-Jan-95 16-Feb-95 16-Mar-95 16-Apr-95 16-May-95 16-Jun-95 16-Jul-95 16-Aug-95 16-Sep-95 16-Oct-95 16-Nov-95 50.00 45.00 40.00 35.00 30.00 25.00 20.00 15.00 10.00 5.00 T 1 It 4 A in I A A 11 i H l i A. As. i J f ^q|_6 -qL7 • L6 samplings 0.00 16-Dec-94 16-Jan-95 16-Feb-95 16-Mar-95 16-Apr-95 16-May-95 16-Jun-95 16-Jul-95 16-Aug-95 16-Sep-95 16-Oct-95 16-Nov-95 FLOW REGIME FLOW REGIME ID < u (✓} Q LU > _i LU 800 700 600 500 400 300 200 100 0 -100 -1-1-1--1-1--1-1-1 1 1 1 1 * 1 I 0 n t ■I l 1 K r u: H: ... ■ r r I ill 1 III Li * * 1y * H 1 3 - 1 11 1 y f 1 rl -' ft * is 1U ■__i_i-1-1-1-1-1-"-1--1-■— 5 6 7 8 9 10 sampling 11 12 0 c1 re I at * Outliers « Extremes 0 q3relat e Outliers * Extremes 0 qfrelat * Outliers ft Extremes B q7relat * Outliers « Extremes degree days increment LnOLnOLnOLnoun OOOOOOOOOO Ln o O O 5T ° o o Ln o LO o o LO O O oo O »J O LO O NJ o 4^ O lt> O Ln degree days increment o o O O Ln O O O 2. g o o Ln O LO O O O LO O 4^ LO O O Ln en o o o o o o O oo o o O O LD O cn O Ln O NJ degree days increment p w w ^ o o o o o o o o o Ln en o o o o 00 o o Ln o 5T ° Ln O o O o O oo O LD O O cn O Ln O LO degree days increment o o O O LO O O O O Ln O O en o o Ln o 01 o o Ln o o o Ln o O oo O LD O O LTl O LO O O Ln en FLOW REGIME - WATER LEVEL VARIATION Fig. 1. water level CV (missing data for L3 S10-S12) FLOW REGIME - WATER LEVEL VARIATION FLOW REGIME - WATER LEVEL VARIATION 60 -| 50 - E u 40 - CD BO c TO 30 - oc s, 20 - ro 10 - 0 - o 7 4 O 1 oo 3 4 6 ViPeaksMAX (hours) L3 2 O 10 60 50 ? o M 5,20 L0 12 0 l; o 3 o J L7 _L'' C 10 15 BrPeaksMAX (hours/day) ZD TEMPERATURE REGIME 24 22 20 18 Ü 16 o cd 14 2 12 cd Cl £ cd cd h—I co 10 8 6 4 2 0 -2 * A I I i r 1T ffl i I 5 6 7 8 sampling 10 T I" ;- f t! TI 8. 11 12 B wtL1 * Outliers B wtl_3 * Outliers B wtL6 * Outliers B wtl_7 * Outliers ABUNDANCE 60000 month TEMPERATURE REGIME X ABUNDANCE TAXONOMIC STRUCTURE AT SITES TAXONOMIC STRUCTURE AT SITES Multidimensional Scaling based on Bray-Curtis dissimilarity Rhefus Paralb Tvedis CHIRONOMID TRAITS Thermal preferences from: Rossaro B., 1991: Chironomids and water temperature. Aquat. Insect. 13: 87-98. 17 16 £ 15 CD u c CD CU 14 o 13 CU O 2 12 Q. DC _ < Q- 11 C l/l E e Oi? CU DC" 10 I T I T _ □ Median □ 25%-75% I Non-Outlier Range o Outliers The, Taxa.mdiAuixcdo^y l>a£&b&se,fi>y Prztkamtw Oyy&iuswM E CU o c CU o u L3 L4 L5 L6 L7 O DC < to to O DC CU U c CU 1_ CU «4- cu Q. "J5 E CU sites sites SEASONAL PATTERNS - DIVERSITY tu so o > cu o > 10 11 12 o > SEASONAL PATTERNS TAXONOMIC DISTANCE AMONG DATES Bray-Curtis dissimilarity L3 Ll x L3 - Bray-Curtis dissimilarity 0,8 -i 0,7 0,6 2 0,5 ] 0,4 0,3 L7 0,6 -i 0,5 -\ U k 0,4 co IV _l 0,3 -I 0,2 0,2 0,5 0,6 Ll Bray-Curtis Ll L6 x L7 - Bray-Curtis dissimilarity 4 • • 2 7 / • 6 3 # • 10 • 8 5 9 • > li s y 12 0,3 0,4 L6 Bray-Curtis 0,5 L6 1J •Z 0,8 .i 0,6 CO CO 1 0,4 -I •Ll •L6 •L3 •L7 -1-1-1-1-1-1-1-1-1-1-1 2 3 4 5 6 7 8 9 10 11 12 dates SEASONAL PATTERNS TAXONOMIC AND INSTAR DISTANCE AMONG DATES TEMPORAL DYNAMICS 0.90 > 0.80 j| 0.70 E 0.60 ro 0.50 t/> 12 0.40 3 U I ^_ 0Q 0.30 0.20 0.10 0.00 * ✓ >•%/ ^X A- \ i V ,___ I tX ^JO"-^ i —*-1 — V I \ » \ 1 w ^^BC-tx - ■•- Q \/ LI -i-1-1-1-1-1-r 3 4 5 6 7 8 9 10 11 12 SAMPLING 500 - 250 0.90 > 0.80 4-> j| 0.70 E 0.60 'i/5 „ _„ ro 0.50 t/> IS 0.40 3 U I ^_ 0Q L3 0.30 0.20 0.10 0.00 ■BC-taxa Q X / x,~« » •■-■•V \ >>—a Vp*^X • V / ■ / / \ i i i i i i i 2 3 4 5 6 7 8 SAMPLING 1 1 9 10 11 i 12 500 o a 0.90 > 0.80 J 0.70 E 0.60 ro 0.50 t/> 12 0.40 3 U I ^_ 0Q L6 0.30 0.20 0.10 0.00 •BC-taxa Q -1-1-1-1-1-1-1-1-1-1- 2 3 4 5 6 7 8 9 10 11 12 SAMPLING 500 450 400 350 300 250 200 150 100 50 0 0.90 > 0.80 4-> j| 0.70 E 0.60 '1/5 „ _„ ro 0.50 =5 * t/> IS 0.40 3 U I ^_ 0Q L7 0.30 0.20 0.10 0.00 -1-1-1-1-1-1-1-1-1-1- 2 3 4 5 6 7 8 9 10 11 12 SAMPLING 500 450 400 350 300 250 200 150 100 50 0 TEMPORAL DYNAMICS SUBFAMILIES 100% -90% - 25000 LI 100% -90% - 25000 L6 80% -70% - 20000 ^■TtsniM2 80% -70% - 20000 ^■TtsniM2 60% - 15000 ^■ChniM2 60% - 15000 ^■ChniM2 50% -40% -30% -20% -10% - 10000 5000 ^■OrthM2 ProdiaM2 DiamM2 ■ TanM2 50% -40% -30% -20% -10% - 10000 5000 ^■OrthM2 ProdiaM2 DiamM2 ■ TanM2 0% - 1 1 1 1 " 1 II 1 1 1 1 1 T 123456789 10 11 12 SAMPLING 0 ^D— Total 0% - 1 1 1 1 1 1 1 1 1 1 1 1 T 123456789 10 11 12 SAMPLING 0 ^^Total 25000 100% -r L3 90% - 20000 80% - ^■TtsniM2 70% - 15000 ^■ChniM2 60% - ^■OrthM2 50% - 10000 ProdiaM2 40% - 30% - DiamM2 5000 20% - ■ TanM2 10% - 0 ^^Total 0% - 123456789 10 11 12 SAMPLING 25000 20000 15000 10000 5000 L7 ITtsniM2 lChniM2 lOrthM2 I ProdiaM2 I DiamM2 ITanM2 ■Total 123456789 10 11 12 SAMPLING 4837 8903 LIFE CYCLES - INSTARS (Polypedilum gr. laetum) CM 1000 100 L3 CM CM site L3 MONTH 1 month delayed occurrence of 4th instar SP ON cu U c ro -a c 3 .Q TO cu > cu 1 Instar Jan Mar May Jul Sep 10 11 12 Nov LIFE CYCLES - INSTARS (Parametriocnemus sty latus) Parametriocnemus stylatus month/site 4 Sum ■■■ 1 1 99 101 2 3 3 6 3 11 39 50 4 1 1 6 4 mm 1 5 12 22 34 6 2 2 1 4 38 3 46 8 2 25 9 36 9 1 8 21 8 38 10 2 11 13 11 3 1 1 5 4 14 12 1 4 151 8 164 Sum 5 1 6 17 41 490 33 593 SP ON CD U C TO ■a c .a (TJ CD > 1 1 10 1 11 12 Instar 10 1 11 12 Instar Jan Mar May Jul Sep Nov SUMMARY • both reservoirs caused deviation in downstream chironomid taxa composition • thermal preferences: decrease and higher variation below Vir Reservoir • sites with seasonally adjusted flow regime (L3, L6) exhibited lower temporal beta-diversity (lower dissimilarity among dates) • even though mesh size and monthly sampling life cycles of selected taxa were observed • analyses of taxa with distinguished instars may provide tool for evaluation of thermally-oriented changes • distinguishing of instars allows better linkages to stage-dependend ecological traits and estimation of biomass