Top PDF The Synergistic Impact of Climate Change and Anthropogenic Management on the Lake Kinneret Ecosystem

The Synergistic Impact of Climate Change and Anthropogenic Management on the Lake Kinneret Ecosystem

The Synergistic Impact of Climate Change and Anthropogenic Management on the Lake Kinneret Ecosystem

affected by anthropogenic intervention, are a typical issue being under crucial scientific and practical research. This is aimed at both prevention of natural and the human society benefits. The Kinneret-River Jordan ecosystem was under complete natural impact until the early 1930s of the previous century, while later on the “Anthropocene Era” of this system was started [5] accompanied by natural climate change. The latest periodical season (1970–2018) was especially a very sensitive factor of significant impact on this system due to two major constrains: (1) water consumption and agricultural development in the watershed and (2) lake water supply. The major changes of regional climate change and the modifications within the Lake Kinneret Limnological trait are briefly presented: elevation of air tempera- ture and Lake Kinneret water, decline of precipitation, agricultural and hydrologi- cal management of the Hula Valley land, decline of lake water level, reduced input loads of nitrogen and phosphorus accompanied by reduction of nitrogen and a slight elevation of phosphorus in the Kinneret Epilimnion, dominance replace- ment of Peridinium by cyanobacteria, chlorophytes, and diatoms. The tentative objective of this paper is aimed at an answer to the question: why and how were those changes developed? It was previously documented [6] that Nitrogen sources for Lake Kinneret are mostly external and mostly effective is nitrate from the Hula Valley Peat soil degradation and fishponds and domestic sewage. Therefore, after removal of sewage and restriction of fishponds, input loads of organic nitrogen were reduced significantly and the supply of nitrate is primarily precipitation- dependent. Nevertheless, input loads of phosphorus from the watershed were reduced but P availability for the Lake Kinneret biota was slightly enhanced due to internal flux from the sediments and dust storm deposition. The dynamic changes of Phytoplankton composition in Lake Kinneret followed the nutrient alterations: the nitrogen consumer Peridinium was declined and cyanobacterial nitrogen fixers were enhanced [7].
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The potential impacts of anthropogenic and climate changes factors on surface water ecosystem deterioration at Kenyir Lake, Malaysia

The potential impacts of anthropogenic and climate changes factors on surface water ecosystem deterioration at Kenyir Lake, Malaysia

Water ecosystem deterioration can be affected by various factors of either natural environment or physical changes in the river basin.. Data observation were made during dry season (April 2017) and wet season (December 2017). 21 sampling stations were selected along Kenyir Lake Basin. Overall, the water quality status as stated in NWQS is categorized as Class I on dry season and Class II on wet sea- son. The major pollutants in Kenyir Lake are Total Suspended Solids (TSS), Chemical Oxygen Demand (COD), Dissolve Oxygen and pH which are contributed largely by untreated or partially treated sewage from tourism development and construction activities around the basin. The sedimentation problem level in the Kenyir Lake Basin is not in critically stage but the flow rate of water and land use ac- tivities (development around basin) will be contributed to the increasing levels of sedimentation. The good site management such as the implementation of proper site practice measures to control and treat run-off prior to discharge will ensure that the construction works will not affect the quality and quantity of the receiving waters or have significant impact upon the receiving waters.
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Limnological Changes in the Lake Kinneret (Israel) Ecosystem: The Beginning and Its Significance

Limnological Changes in the Lake Kinneret (Israel) Ecosystem: The Beginning and Its Significance

The Kinneret ecosystem has undergone significant changes: WL decline (lower TSS density under WL de- cline but no periodical change Figure 10), Temperature increase [6] [11] (Figure 8), pH (slightly higher during 1990-2001) (Figure 11), hydrological components (water inputs and output, precipitation,) phytoplankton community composition (Peridinium decline, Cyanobacteria proliferation) [8], fishery management (the decline of Sarotherodon galilaeus and Bleaks enhancement) nutrient dynamics (N/P mass ration) and more. Commonly, such modification are respected as the principle changes. Nevertheless, temporal analysis of TSS fluctuation during the period assigned as change initiation has indicated a level of stability that the ecosystem responded to. The WL decline, for example, did not stimulate long-term modification and the optional repeated process of Pe- ridinium blooming was documented. Moreover, as documented here, quantitative mass changes of TSS/Plank- ton/Detritus ratio were not accompanied. Climate changes [13] precipitation decline and, consequently, river discharges are an obvious linkage which is followed by WL decrease. The question is, were those changes also a response of Peridinium disappearance? The change of phytoplankton assemblages is probably due to the change of nutrient dynamics, i.e. the shift from N to P limitation [8]. The decline of Sarotherodon galilaeus landings was ascribed to natural long-term cycling of their population size as well as to the enhancement of predation by Cormorant, fish disease infection, illegal usage of small mesh size nets, and decline of stocking. Therefore, anthropogenic improvement confirmed positive renewal. The fluctuations of the zooplankton communities (Figure 1) is attributed to the elimination of the zooplanktivorous Bleak fishery. Conclusively, the basic eco- system structure was not modified and management improvements were efficient. The mass ratio between the major components in the epilimnion were not modified. The seasonal activities of the living fraction of the TSS compartment (Figure 4 and Figure 5) indicate differences: dominance of plankton and consequently total TSS in winter and their decline in summer when Detritus fraction is dominant. The winter Phytoplankton increase is also reflected by the documented values of Secchi depth (Figure 12) which become shallower but deepen in summer. Those seasonal and periodical dynamics are also reflected in the Particulate N and P contents: high in winter and low in summer (Figure 6) and positive direct relation (Figure 7).
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Predictability of Ecological Changes in Lake Kinneret

Predictability of Ecological Changes in Lake Kinneret

mcm/y), Lake Kinneret, was the national major source for domestic water supply. The Kinneret ecosystem has undergone man-made and natural modifi- cations: dam construction (1933), salty water diversion (1967), salinity fluctua- tions, National Water Carrier construction (1957), fish stocking and fisheries management, long term decline and increase of water level, droughts and floods, modification of phytoplankton biomass and species composition, beach vegeta- tion; nitrogen decline and a slight increase of phosphorus in the lake epilimnion; decline of nitrogen loads in the Jordan River; decline of the epilimnetic N/P mass ratio, followed by enhancement of cyanobacteria. The Kinneret ecosystem shifted from P to N limitation. The decline of water level is due to both natural droughts and surplus pumping. Decline in nitrogen in the Kinneret epilimnion was probably due to both the reduction of river discharges (droughts) and a lower N contribution from the drainage basin, as a result of anthropogenic ac- tivities. The Hula old Lake and swamps in the vicinity were drained and land was converted to agricultural development; most of the sewage (human and fishpond effluents) was eliminated from the lake; conclusively, the change in the Kinneret ecosystem structure by shifting from P to N limitation was affected by both the anthropogenic and natural processes. Those changes implemented from 1933 and onwards [1].
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The Impact of EL NINO/Southern Oscillation (ENSO) on Fishery and Water Quality in Lake Kinneret (Israel)

The Impact of EL NINO/Southern Oscillation (ENSO) on Fishery and Water Quality in Lake Kinneret (Israel)

last 20 years, the Kinneret ecosystem structure has undergone significant modifications. The major change was a turnaround of nutrient availabilities from Phosphorus to Nitrogen limitation within the biotic compartments of the ecosystem [1]. The algal dominance of the bloom, forming Pyrrhophyte Peridinium, was replaced with Cyanobacteria, and the fish food resources were modified, respectively. Independently, other external, natural and anthropogenic constraints created an additional pressure on the fishery: population increase of the migratory fish predator, Great Cormorant (Phalacrocorax carbo) in the lake, reduction in stocked fingerlings of the cichlid, Sarotherodon galilaeus (SG), the use of illegal small mesh sized fishing nets, the elimination of Bleaks fishing, and the outburst of Virus disease, which mostly infected Tilapias. It is most likely that the climatic conditions also resulted in fluctuations of the population size as well as that of SG. SG is a species of fish on top priority in the fishery management design, and it is aimed at water quality protection and fisher’s income. During the year 2007-2008, landings of S. galilaeus sharply declined from an earlier amount of 200 - 400 tons annually to less than 10 tons in the year 2008 [1]. Among several other potential reasons for the decline of SG landings, the re- levance of climatic conditions periodicity was also considered. In this paper, the analysis of correlation between SG fishery and the periodical impact of EL-NINO/Southern Oscillation Index (ENSO) was presented.
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Assessment of Impacts of Climate Change on Hydro-meteorological  Ecosystem Services and Water Stress in Lake Kyoga Catchment

Assessment of Impacts of Climate Change on Hydro-meteorological Ecosystem Services and Water Stress in Lake Kyoga Catchment

Conclusion: Anthropogenic activities have contributed to changing patterns of extreme weather across the globe, ranging from longer and hotter heat waves to heavier and erratic rains. These events are all anticipated to be as a result of climate change. (Gervais.F.2014). While climate variability and change continue to impact as more extreme events are anticipated to occur as result of increased temperatures and change in rainfall intensities, both extremes will have an impact on the river flows as erratic and heavy rains will lead to more floods, soil erosion among others and a reduction results into prolonged droughts/ water scarcity. As more understanding of how climate change will affect extreme weather is still developing, it’s more likely that extreme weather may be affected even more than anticipated as the extremes are on the rise an indication that they will continue both in predictable and unpredictable ways.
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The Impact of Available Nitrogen Deficiency on Long Term Changes in the Lake Kinneret Ecosystem

The Impact of Available Nitrogen Deficiency on Long Term Changes in the Lake Kinneret Ecosystem

As a result of over utilization and natural droughts, the Water level in the lake fluctuated at an amplitude of approximately 6 meters. The lake is also under heavy fishery utilization and fishery management including in- troduction of native and exotic species [6] [7]. Salts diversion was carried out and the lake water chloridity fluc- tuated between 210 and 300 ppm chloride. Hula Old Lake and Swamps in the Hula Valley (drainage basin) were drained [4] and domestic sewage was eliminated from the Kinneret inputs and fishpond effluents were reduced dramatically [8] [9]. Agricultural practices in the catchment area were changed also. Regional air temperatures and consequently lake water were increased and heat balance and precipitations were modified. Changes of phytoplankton composition and density within the Kinneret ecosystem were documented. When anthropogenic and natural changes are accompanied by both eutrophication and global changes, it is possible that impact rein- forcement of each other is carried out. Consequently, the evaluation of the process dynamics involved in the transition of Lake Kinneret ecosystem between different structures may be confounded and/or misleading. Long- term changes in the subtropical Lake Kinneret were widely documented followed by impact evaluations of cli- mate changes and anthropogenic factors. The major criteria of impact were mostly related to water level fluctua- tions constrained by water consumption and droughts. In this paper, I present an attempt aimed at sole element of ecological trait, available Nityrogen, which might be the dominant factor which enhances the recorded changes.
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The Impact of Water Level Decline on Water Quality in the Epilimnion of Lake Kinneret (Israel): Perennial Perspectives

The Impact of Water Level Decline on Water Quality in the Epilimnion of Lake Kinneret (Israel): Perennial Perspectives

The Kinneret ecosystem has undergone significant changes during the last 70 years. Some of the changes are natural like droughts and floods, and others are anthropogenic like land-use in the drainage basin or fishery and salts diversion in the lake. Increasing population up to above 200,000 inhabitants in the drainage basin, sewage removal and fishpond restriction in the catchment, operating new agricultural technologies (crop types, irrigation) and development of eco-tourism [2]-[4]. The Lake Kinneret water quality is of a national concern therefore the lake is depends on the nation and the nation is depends on the lake [2] [3]. The lake supplies 16% - 30% of the national water demands and >55% of drinking water requirements. Kinneret is a warm monomictic lake which is stratified from May through mid December (anoxic hypolimnion) and totally mixed during mid December through April. Among fluctuations of lake conditions are high (6.3 m) amplitude of water level (208.57 - 214.87 mbsl); high inflow discharges (>10 9 m 3 per annum) and droughts (<260 × 10 6 m 3 per annum); low (333 mm/y) and high (1060 mm/y) precipitations in the drainage area; plankton biomass and composition changes, fish stocks, epilimnetic temperatures and nutrient concentrations. The seasonal pattern of the distribution of hydro- logical, chemical and biological parameters consistently represents subtropical climate conditions: high levels in winter and low in summer months but high hypolimnetic inventories of dissolved phosphorus, ammonium, sul- fides and CO 2 in summer-fall period as a result of the thermal and chemical stratification.
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The Ecological Outcome of Climate Change in Lake Kinneret—Thermal Pollution

The Ecological Outcome of Climate Change in Lake Kinneret—Thermal Pollution

Surface water heat fluctuates very little (±0.5˚C) under high WL (>211 mbsl). Under low WL (<211 mbsl), the temperature of surface water increases with WL decline (211 - 214 mbsl). The temperature of deeper layers during high WL de- creased. A direct positive relationship between the temperature of the air and surface waters was indicated when the air temperature was higher than 21.5˚C with a surface temperature >23.5. Consequently, it is suggested that surface wa- ter is affected by air heating and partly also by upward Heat Conductivity from deeper layers. Conclusively, the thermal impact is related to air warming, preci- pitation decline and water warming. Because the outcome of warming lake water is an enhancement of the metabolic activity of the lake biota, the appropriate management design is shortening of water residence time by enhancement of water exchange. This study exemplifies that even minor thermal fluctuations might be a signal of ecological modification. The only thermal measure of de- grees might be insignificance for a lake under water input reduction accompa- nied by WL and volume decline.
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Temperature Impact on the Shannon Wiener Biodiversity Index (BDI) of Zooplankton in Lake Kinneret (Israel)

Temperature Impact on the Shannon Wiener Biodiversity Index (BDI) of Zooplankton in Lake Kinneret (Israel)

Wang et al. [1] [2] documented the greatest level of dependence between Bio- diversity and Temperature at the extreme nutrient level, confirming the direct effect of Temperature and nutrients on Biodiversity. Consequently, future cli- mate scenarios such as global warming could alter Biodiversity. The positive re- lations between temperature and species richness (Biodiversity) were widely documented [1] [2] [3] [4]. The impact of Biodiversity on ecosystem productiv- ity [5] and relationships between Phosphorus and richness of species in lakes and rivers [6] were previously documented. A systematic review and me- ta-analysis on the interactions between climate and effects of habitat loss on Biodiversity [7], and the impact of nutrient enrichment on loss of Biodiversity and consequent declines in ecosystem productivity [8] are only few examples from the huge mass of documentation about the ecological impacts on Biodiver- sity traits in aquatic habitats. The global ecological role of aquatic conditions and the involvement of water in climate change, particularly biosphere warming, were considered by Parsons [3] and [4]. As on a global scale, the close relations between Biodiversity decline along latitude-elevation were widely documented [2] [9]. The crucial concern is the impact of climate change on the future of Bio- diversity [1] [10] (and many others). The objective of the present paper is an at- tempt at correlating zooplankton diversity to temperature aimed at potential water quality modification. For the evaluation of this study, long-term Kinneret records of Zooplankton and Epilimnetic temperatures were analyzed. The correlations between periodical fluctuations of the “Shannon and Wiener Alpha Index of Bio- diversity” (BDI) and the Kinneret Epilimnion Temperature records were analyzed.
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Can climate finance in Bangladesh be helpful in making transformational change in ecosystem management?

Can climate finance in Bangladesh be helpful in making transformational change in ecosystem management?

5. Goals and targets for transformational development should explicitly acknowledge that reducing climate vulnerability helps achieve goals on poverty, food security and other basic development priorities. At the same time, international climate change debates and initiatives should give more attention to ensur- ing they benefit development. Both international cli- mate change processes and international agendas on poverty reduction and sustainable development can learn from the innovative ways individual countries are bringing together these issues, and the funding to address them, at national levels. To support these synergies, climate finance instruments should be designed and governed in ways that aim to deliver such co-benefits, thereby helping achieve globally agreed development goals (IIED:Briefing 2013). Climate fiscal framework for sustainable climate financing for ecosystem management
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Land Use, Climate Change and Ecosystem Services

Land Use, Climate Change and Ecosystem Services

We use the data described in section 3.1.2 to estimate (1) and (2). For each equation we use a log-linear specification, and a one-way fixed effects model to capture unobserved cross- sectional heterogeneity 9 . In the pond equation (1), we include temperature (T) one- and two-year lags for precipitation (P) because prairie wetlands are dependent on accumulated soil moisture (Sorenson et al. 1998), and the change in the crop share ( Δ CS) as changes in crop area better capture potential wetland loss. In the duck equation (2), we include the current year and one-year lag of ponds, the crop share and the lagged harvest (H) since birds are harvested in the fall and thus affect the following spring migration. The regressions fit the data well with R 2 of 0.75 and 0.83 for the pond and waterfowl models, respectively, and highly significant F-statistics. The estimated equations, with fixed effects omitted for simplicity and p-values in parentheses, are: (3) ln(Ponds) = 13.76 – 0.04*T + 0.01*P + 0.09*P t-1 + 0.14*P t-2 – 1.49* Δ CS
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Assessing the Influence of Global Climate and Anthropogenic Activities on the Water Balance of an Andean Lake

Assessing the Influence of Global Climate and Anthropogenic Activities on the Water Balance of an Andean Lake

Tropical regions along the Andean Cordillera face an uncertain future as mountain lakes and snow peaks ex- hibit receding trends associated with factors such as climatic precursors and local anthropogenic activities. Tota, the largest mountain lake in the Colombian Andes, exemplifies the role played by these factors on the lake's hydrologic evolution. A monthly water balance in Tota Lake was performed using available hydro- logical information from 1958 to 2007 to address interannual and multiannual level fluctuations associated with human activities and climatic precursors. The balance shows that net water uses fluctuated around 2 m 3 /s during this period with a pattern that, although constrained during years of severe decline in lake levels, is able to explain most of the multiannual decaying trend of 1.5 cm/year in the last 50 years. The lake’s naturalized levels were used to determine the influence of climate precursors on the lake evolution. Using Multichannel Singular Spectrum Analysis (M-SSA), significant five-year ENSO and 20-year PDO related quasi-oscillations were detected, explaining 54% of the variance associated with mean annual naturalized level fluctuations. ENSO is markedly in-phase with lake levels, with critical declines associated with low precipitation and high evaporation rates during El Niño years, whereas the PDO signal exhibits a phase op- position with lake levels, with low naturalized levels during a positive PDO phase and high levels during a negative PDO phase (an important result to consider given the current cooling trend of the PDO signal).
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Hydrological Impact Assessment of Climate Change on Lake Tana’s Water Balance, Ethiopia

Hydrological Impact Assessment of Climate Change on Lake Tana’s Water Balance, Ethiopia

In this study, climate change impact for Lake Tana basin area is assessed at monthly time step by using downscaled GSM outputs that serve as input to hydrological models. We simulate the lake water balance for all three time periods and assess the pattern of hydrological alteration by summing model-simulated stream-flow from gauged and ungauged catchments, and by estimating over-lake precipitation and lake evaporation. In the approach, the stream flow from ungauged catchments is estimated by the HBV (Hydrologiska Byrans Vattenba- lansavdelning) hydrological model [5] using model parameters by a regionalization study in the Lake Tana basin [6]. For the baseline period as well as the three future time periods windows the same HBV model parameters are applied that as such remain unchanged.
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Timing anthropogenic stressors to mitigate their impact on marine ecosystem resilience

Timing anthropogenic stressors to mitigate their impact on marine ecosystem resilience

Globally consistent timing of ecological windows across dredging scenarios of similar durations were observed, despite variability in local conditions including depth, subtidal vs. intertidal, baseline light conditions and tropical vs. temperate climate, as well as differences among life histories of the seagrass genera. Therefore, scheduling of dredging according to time of year, where many sites with different local environmental conditions share the same window, provides a powerful tool for maximising resilience under uncertainty. For example, Austral April–May and Boreal October–November is one such seasonally consistent window for opportunistic meadows being dredged for 3 months (Fig. 3) despite meadow locations ranging from 38 south to 64 north latitude and irrespective of differences in light conditions among locations (Fig. 4). For dredging durations of up to 3 months, windows also tended to align with autumn and winter for enduring-colonising and opportunistic meadows. Persistent meadows were generally resistant to small stressors independent of when they occurred while transitory colonising meadows tended to display narrow windows around late summer early autumn (Austral January–February; Boreal July–August for 3 months dredging).
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Low Mercury Levels in Lake Kinneret Fish

Low Mercury Levels in Lake Kinneret Fish

The widespread occurrence of unacceptable levels of MeHg in fish and seafood is due, in part, to the fact that human activities such as coal-power generation have greatly increased the global pool of inorganic mercury released into the atmosphere (Lindberg et al., 2007). Atmospheric mercury has a lengthy residence time, allowing for long-range dispersal before it is eventually deposited to aquatic ecosystems and their watersheds. Inorganic mercury from atmospheric deposition is converted to MeHg by sulfur-reducing bacteria, a process that occurs primarily in anoxic environments such as lake sediments and hypolimnia of stratified lakes (Gilmour et al., 1992). MeHg readily bioaccumulates and biomagnifies in aquatic food webs, resulting in MeHg concentrations in top predatory fish that can be a million-fold greater than the concentration in the water (Bowles et al., 2001). Subsequently, dietary exposure and food chain length can be important determinants of MeHg concentration among fish species. For example, fish that eat phytoplankton (primary consumers) have lower MeHg concentrations than fish that feed at higher trophic positions on zooplankton, benthos, or fish (Wiener et al., 2003). MeHg binds to proteins in fish muscle and is eliminated very slowly from this tissue (Van Walleghem et al., 2007), further contributing to high MeHg concentrations in the fish that humans consume.
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The Ecology of Keratella cochlearis in Lake Kinneret (Israel)

The Ecology of Keratella cochlearis in Lake Kinneret (Israel)

conditions for Keratella food resources. Their availabil- ity is high and the abiotic conditions are suitable. Thus, winter populations of Keratella are larger and more pro- ductive (higher number of egg bearing females and E/F) (Table 2; Figure 2). The lower rates of change in winter (Table 2) are indicated by the higher level of stability and lower death rate values (Table 2). The long term analysis (Table 3, Figure 3) implies that the populations, during 1972-1985, when droughts were less frequent [6], were notably more stable, healthy and productive. The lower death and birth rate values, as well as the longer turnover time and higher densities, enhanced these fea- tures. During 1986-2000, droughts became more frequent, runoff discharges declined, and water temperature in- creased [6,12]. Consequently, it was suggested that food source renewal and the shift of the Kinneret ecosystem from a P to N limitation [8], with a lower productivity (a lower N content in suspended particles), caused suppres- sion of Keratella communities (Figure 1). It is proposed that the change in phytoplankton composition, from Peridinium to nano-phtoplankton dominancy [8,9,12], affected the nutritional value of Keratella food sources. The seasonal fluctuations of the population dynamics parameters, presented in Figure 4, imply that the sup- pression of summer (May - Sep.) Keratella populations (Nt < No, see equation 4) is probably a result of food availability and temperature constraints. Productive and healthy assemblages were present in winter (Oct. - Dec. and Feb. - Apr.). The reason for exceptionally low values of instantaneous birth and death rates in October (Figure 4) is unclear.
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Reconciling anthropogenic climate change and variability on decadal  timescales: the challenge

Reconciling anthropogenic climate change and variability on decadal  timescales: the challenge

Paired variables sometimes maintain stationarity across regime changes while at other times may become  nonstationary. Shits that maintain stationarity represent regime changes occurring[r]

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Population Dynamics of Cyclopoid Copepods in Lake Kinneret (Israel)

Population Dynamics of Cyclopoid Copepods in Lake Kinneret (Israel)

Reports on the Kinneret zooplankton in general and particularly on copepods are recently dealing with numerical densities of feeding habit classes. Nevertheless, for the evaluation of the integrated role of copepod assemblages in the entire lake eco- system, their life cycle stages fluctuations are essential. It was not done in previous reports. Therefore, long term analysis of the cyclopoid copepods life stages dynamics in Lake Kinneret was carried out. Due to information availability, two complemen- tary methods of density concentrations were evaluated for two consecutive data sets: 1) 1969-1985 numerical (No/L) documentation of life cycle stages of nauplii (I - III and III - V), copepodites (I, II, III, IV, V) and adults; 2) 1969-2002 monthly averages of wet biomass density (g/m 2 ) of zooplankton major groups combined with metabol-
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The burial efficiency of organic carbon in the sediments of Lake Kinneret

The burial efficiency of organic carbon in the sediments of Lake Kinneret

These calculations may be compared with the initial analysis of OC BE in Lake Kinneret (Sobek et al. 2009 ), which used published sediment trap-based dry mass deposition rates (Koren and Klein 2001), multiplied with the OC content in surficial sediment layers. At the shallow sites, the three different approaches of calculating OC BE agreed fairly well (Table 3 , Fig. 3 ), returning burial effi- ciencies of about 10–30%. At the deep site (KI-C), however, the OC BE of the initial analysis (63%; Sobek et al. 2009 ) was considerably higher than both the burial efficiency calculated from multiannual trap data (if cor- rected for resuspension), and the burial efficiency calculated from OC mineralization (41 and 26%, respec- tively). Hence, the two alternatively calculated estimates of OC BE presented here both indicate that in the initial analysis (Sobek et al. 2009 ), OC BE at site KI-C was overestimated. A recent evaluation of sediment trap deployments in Lake Kinneret supports that view, reporting an OC deposition (unaffected by resuspended matter) of about 173 g C m -2 year -1 at KI-C (Ostrovsky and Yacobi 2010 ), which would return an OC BE at KI-C of about 31%. As a consequence, an OC BE for KI-C in the range of 26–41% follows the relationship between oxygen exposure time and OC BE reported by Sobek et al. ( 2009 ), as expected for a sediment that receives OC mainly from plankton debris (Fig. 4 ).
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