2007 Wetland Inventory for the Eyre Peninsula

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Survey ResultsTurbidity values were generally below 30 NTUs with the exception of two sites, S3034 (lake Greenly) with areading of 1000 NTUs and S3035 (Big Lake Malata) with 721 NTUs. Both of these sites displayed fine siltyclay particles that obviously clouded the water column. The water depth was less than 15 cm and the landsurrounding the waterbody was generally cleared. It is assumed that the combination of these factors,particularly the soil characteristics, contributed to these high NTU readings.Many sites that contained moderate to high salinity levels tended to record a very low turbidity reading,generally zero. To put the survey readings in perspective the guidelines used by the NSW EPA have beenadopted. Interpreting these results should be done with caution, as other water chemistry factors play a partin the overall health of a wetland.Table 2. Turbidity guidelines.Guideline NTUs Number of WetlandsGood 50 2(lake Greenly and Big LakeMalata)21.4 Water TemperatureMany of the physical, biological and chemical characteristics of a wetland are directly affected bytemperature. Temperature affects the solubility of oxygen in water with warmer water holding less oxygenthan cooler water. These factors affect the rate of photosynthesis by algae and larger water plants, withwarm water temperatures being susceptible to eutrophication and therefore algal blooms. The sensitivity oforganisms to toxic waste, parasites and diseases is also related to water temperature. Organisms canbecome stressed as temperatures rises and become less resilient to other stresses, this results in mostaquatic organisms having a narrow temperature range in which they can function effectively.Most aquatic organisms are cold-blooded which means they are unable to internally regulate their corebody temperature. Therefore, temperature exerts a major influence on the biological activity and growth ofaquatic organisms. To a point, the higher the water temperature, the greater the biological activity. Fish,insects, zooplankton and other aquatic species all have preferred temperature ranges. As temperatures gettoo far above or below this preferred range, the number of individuals of the species decreases until finallythere are few, or none.The most obvious reason for temperature change in lakes is the change in seasonal air temperature waterlevel. Daily variation also may occur, especially in the surface layers, which are warm during the day andcool at night. In deeper lakes (typically greater than 5 m for small lakes and 10 m for larger ones) duringsummer, the water separates into layers of distinctly different density caused by differences in temperature,this process is called thermal stratification.When the surface water cools again in the fall to about the same temperature as the lower water, thestratification is lost and the wind can turbulently mix the two water masses together because their densitiesare so similar. A similar process also may occur during the spring as colder surface waters warm to thetemperature of bottom waters and the lake mixes. The lake mixing associated with a turnover oftencorresponds with changes in many other chemical parameters and this can affect biological communities(The National Advisory Committee to Water on the Web 2001).40
For aquatic systems the maximum recommended increase in the natural temperature range of any inland ormarine water is 2 0 C (Waterwatch Manual 1994). Because the surveys have recorded the first readings formany wetlands, this natural temperature range is largely unknown. As a general guide, temperaturesbetween zero and 20 degrees are acceptable limits for Mediterranean climates, while temperatures over 20degrees can start impacting on aquatic fauna and fauna (Waterwatch Manual 1994).24.4.1 AnalysisThe average water temperature was 19 degrees, with temperature variations between 11degrees (EllistonHamp Lake) and 26 degrees being recorded. The influencing factor in wetland temperatures on EyrePeninsula is that the majority of water bodies are very shallow, usually no more than 60 cm in depth. Thetime of sampling will also effect temperature ranges, readings taken early in the morning will be muchdifferent from temperatures in the afternoon. Temperature readings are required over several time periodsand during different seasons to attain a true indication of temperature regimes.22.0 RAPID ASSESSMENTThe rapid assessment component of the survey provides a quick snap shot of the condition within differentriparian habitats. Generally the score is a subjective one given by the observer, it is an estimate ofpercentage of intact native vegetation and the diversity and abundance of aquatic flora and fauna.22.1 Aquatic FaunaThis is a subjective score according to the abundance and diversity of invertebrates, fish and birds locatedwithin or on the water body. Low (1) refers to no fish or birds with little or no invertebrate presence, Moderate (3) refers to some bird presence and good vertebrate abundance, fish usually are not present, High (5) indicates good bird and invertebrate diversity and abundance with the presence of fish.Aquatic Fauna Score30%15%55%1 = Low3 = Moderate5 = HighFour sites received a low score (Pillie Lake, OldPlough Swamp, Lake Greenly and Samphire Flat).Fifteen sites scored a moderate score and eightsites scored a high score (eg Orana Swamp).Figure 16. Aquatic Fauna Rapid Assessment41
Page 3: Executive SummaryThe Wetland Invent
Page 7 and 8: PLATESPLATE 1. MELALEUCA HALMATUROR
Page 9 and 10: 4.0 OVERVIEW OF WETLAND INVENTORY T
Page 11 and 12: 6.3 GIS DatabaseThis project builds
Page 13 and 14: SECTION TWOWETLAND ASSESSMENT FOR E
Page 15 and 16: 10.0 TENURE AND MANAGEMENT AUTHORIT
Page 17 and 18: Bay, Sleaford Mere and Kathai Conse
Page 19 and 20: 14.0 LANDFORM ELEMENT14.1 Backgroun
Page 21 and 22: 16.0 HYDROLOGY16.1 BackgroundThe we
Page 23 and 24: Melaleuca halmaturorum infull flowe
Page 25 and 26: 19.0 AQUATIC VEGETATION CLASSES19.1
Page 27 and 28: GrazersGrazers consist of aquatic s
Page 29 and 30: Table 1. Invertebrate abundanceInve
Page 31 and 32: Plate 8. Old Plough Swamp. Plate 9.
Page 33 and 34: Brock and Boulton (1999) state that
Page 35 and 36: Effects on biodiversitySecondary sa
Page 37 and 38: Plate 12. Hamp LakeHamp Lake (S3025
Page 39: 100,00010,0001,000100FishAbandonCov
Page 43 and 44: 25.0 RAPID ASSESSMENT TOTAL SCORETh
Page 45 and 46: 26.1 AnalysisOf the 27 wetlands sur
Page 47 and 48: 13. Shrub swamps, shrub dominated f
Page 49 and 50: SECTION THREEWETLAND MONITORING28.0
Page 51 and 52: 29.0 MONITORING PROTOCOLS AND INDIC
Page 53 and 54: Attributes of rapid assessment incl
Page 55: 31.1 Recommended priority wetlandsT
Page 58 and 59: Lloyd, B.(1986). Wetlands & Water R
Page 60 and 61: APPENDIX 1Wetland Inventory descrip
Page 62 and 63: Salt lake: Lake, which contains a c
Page 64 and 65: Conservation measures taken and mea
Page 66 and 67: Water Temperature: Water temperatur
Page 68 and 69: Photographic recordsPhotographic re

2007 Wetland Inventory for the Eyre Peninsula

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