scholarly journals Innovated Management Design of Lake Kinnere (Israel) and its Drainage Basin

2016 ◽  
Vol 3 (1) ◽  
pp. 1 ◽  
Author(s):  
Moshe Gophen

<p>During the last 80 years, the Lake Kinneret and its Drainage Basin ecosystems have undergone significant anthropogenic and natural modifications. Man made operations in the drainage basin and in the lake, accompanied by natural climatic conditions, resulted in modifications of the ecosystem structure. Old lake Hula and swamps were dredged and were being converted for agricultural development. Years later, the partial land utilization was modified, in an operation, referred to as the Hula Project operation. Twenty years later, several improvements for the Hula Project structure are suggested. Regimes of nutrient inputs into Lake Kinneret were changed by a decline in Nitrogen influx. Air and epilimnetic water temperature increase, as well as change of the nutrients composition. The lake ecosystem was shifted from P to N limitation. The phytoplankton and fish communities in the lake, were respectively modified. There were enhancements in N<sub>2</sub>-Fixing Cyano-bacteria and Bleak fishes beside the partial decline of tilapias. The impact of Albedo and ENSO (EL-NIÑO/SOUTHERN OSCILLATION) factors is indicated. A combined impact of the natural and anthropogenic parameters are involved. An innovation in the management design within the lake, and the drainage basin ecosystems are suggested: 1: Cutoff of beach vegetation along 20% of the shoreline length enabling public recreation; 2: Intensification of Bleak and improvement of Tilapias fisheries aimed at both, the fishers’ income and the water quality improvement; 3) Slight changes in the Hula Project structure.</p>

2020 ◽  
pp. 1-12
Author(s):  
Moshe Gophen

The long-term record of River Jordan-Lake Kinneret ecosystem indicates some significant climate condition changes: water temperature increase, decline in rainfall, and diminishing river discharges and lake water inflows accompanied by a reduction in nitrogen and a slight increase in phosphorus in the Lake upper layers (Epilimnion). Lake Water level decreased, Prolongation of Residence Time was documented, nutrient inputs and dynamics modifications resulting water quality deterioration. As a result of temperature elevation and nitrogen deficiency, the biomass of Peridinium spp significantly reduced and was replaced by Cyanobacterial biomass enhancement. Dryness trend expressed as enhanced frequency of drought seasons initiated an elevation of lake water salinity. It has been suggested that these changes in the phytoplankton community structure are caused by regional climate change. This study evaluates a multi-annual respective approach although the summer is the most critical. The objective of this research is evaluate the background of the ecosystem structure modification aimed at define future potential management design.


Hydrology ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 61 ◽  
Author(s):  
Kleoniki Demertzi ◽  
Dimitris Papadimos ◽  
Vassilis Aschonitis ◽  
Dimitris Papamichail

This study proposes a simplistic model for assessing the hydroclimatic vulnerability of lakes/reservoirs (LRs) that preserve their steady-state conditions based on regulated superficial discharge (Qd) out of the LR drainage basin. The model is a modification of the Bracht-Flyr et al. method that was initially proposed for natural lakes in closed basins with no superficial discharge outside the basin (Qd = 0) and under water-limited environmental conditions {mean annual ratio of potential/reference evapotranspiration (ETo) versus rainfall (P) greater than 1}. In the proposed modified approach, an additional Qd function is included. The modified model is applied using as a case study the Oreastiada Lake, which is located inside the Kastoria basin in Greece. Six years of observed data of P, ETo, Qd, and lake topography were used to calibrate the modified model based on the current conditions. The calibrated model was also used to assess the future lake conditions based on the future climatic projections (mean conditions of 2061-2080) derived by 19 general circulation models (GCMs) for three cases of climate change (three cases of Representative Concentration Pathways: RCP2.6, RCP4.5 and RCP8.5). The modified method can be used as a diagnostic tool in water-limited environments for analyzing the superficial discharge changes of LRs under different climatic conditions and to support the design of new management strategies for mitigating the impact of climate change on (a) flooding conditions, (b) hydroelectric production, (c) irrigation/industrial/domestic use and (d) minimum ecological flows to downstream rivers.


2020 ◽  
Author(s):  
Katrina A. Moser ◽  
Elizabeth J Hundey ◽  
Maria E. Sia ◽  
Rebecca M. Doyle ◽  
Holly Dunne ◽  
...  

&lt;p&gt;Mountain lakes are often remote, located in environments that experience cold temperatures, high incident solar and ultraviolet radiation, and prolonged ice and snow cover. They are, therefore, frequently dilute and oligotrophic. Together these factors can a&amp;#64256;ect mountain lake ecosystem structure, diversity, and productivity. However, distant human activities resulting in atmospheric pollution, as well as more local disturbances, such as fish stocking, potentially increase nutrient inputs and alter mountain lake ecosystems. Our research addresses how these human activities have altered algal production in Uinta Mountain (Utah, USA) lakes. Sedimentary chlorophyll a and its derivatives were measured using visible reflectance spectroscopy in short sediment cores from a total of 12 lakes, including both alpine and subalpine lakes, to determine trends in algal production. All sediment cores were dated using &lt;sup&gt;210&lt;/sup&gt;Pb and &lt;sup&gt;14&lt;/sup&gt;C dating, and the records were shown to extend back 300 to 500 years. Our results show that regardless of whether lakes were stocked or not, algal production remained virtually unchanged until 1950 when it increased dramatically in most lakes. The widespread distribution of the sites points to a regional stressor, such as atmospheric deposition of nutrients, as being the main cause for increased algal production. Additional analyses, including diatoms and C and N isotopes, measured in sediments from some lakes support this finding. The few lakes where algal production trends differed showed either that algal production had changed little overtime or that it was variable throughout the record. Although speculative, the lake that showed unchanged algal production is surrounded by a wetland that may have contributed nitrogen to the lake throughout the record meaning that additional nitrogen had little effect on algal production. Lakes with more variable algal production were subalpine lakes. The variable trend may point to more complex pathways and transport of nitrogen from the catchment to the lakes at lower elevation sites. Our findings show that remote mountain lakes, which typically are important water resources and biodiversity hotspots, are rapidly changing as a result of human activities, but not all of these lakes are responding in the same way. To effectively protect mountain lakes it will be important to identify and quantify influential factors affecting lake response to anthropogenic stressors.&amp;#160;&amp;#160;&lt;/p&gt;


2020 ◽  
pp. 50-64
Author(s):  
Kuladeep Kumar Sadevi ◽  
Avlokita Agrawal

With the rise in awareness of energy efficient buildings and adoption of mandatory energy conservation codes across the globe, significant change is being observed in the way the buildings are designed. With the launch of Energy Conservation Building Code (ECBC) in India, climate responsive designs and passive cooling techniques are being explored increasingly in building designs. Of all the building envelope components, roof surface has been identified as the most significant with respect to the heat gain due to the incident solar radiation on buildings, especially in tropical climatic conditions. Since ECBC specifies stringent U-Values for roof assembly, use of insulating materials is becoming popular. Along with insulation, the shading of the roof is also observed to be an important strategy for improving thermal performance of the building, especially in Warm and humid climatic conditions. This study intends to assess the impact of roof shading on building’s energy performance in comparison to that of exposed roof with insulation. A typical office building with specific geometry and schedules has been identified as base case model for this study. This building is simulated using energy modelling software ‘Design Builder’ with base case parameters as prescribed in ECBC. Further, the same building has been simulated parametrically adjusting the amount of roof insulation and roof shading simultaneously. The overall energy consumption and the envelope performance of the top floor are extracted for analysis. The results indicate that the roof shading is an effective passive cooling strategy for both naturally ventilated and air conditioned buildings in Warm and humid climates of India. It is also observed that a fully shaded roof outperforms the insulated roof as per ECBC prescription. Provision of shading over roof reduces the annual energy consumption of building in case of both insulated and uninsulated roofs. However, the impact is higher for uninsulated roofs (U-Value of 3.933 W/m2K), being 4.18% as compared to 0.59% for insulated roofs (U-Value of 0.33 W/m2K).While the general assumption is that roof insulation helps in reducing the energy consumption in tropical buildings, it is observed to be the other way when insulation is provided with roof shading. It is due to restricted heat loss during night.


ABSTRACT The ecosystem services provided by wetlands can be direct or indirect. The direct services can be mostly valued through market prices, but the indirect service like aesthetic beauty and its impact on property prices surrounding the natural resource cannot be directly measured. To single out the economic effect of particular amenity which influenced the land property prices, the advanced valuation technique Hedonic property pricing was most popularly used. In this study, it was attempted to assess using the hedonic property pricing technique, the impact of the presence of the freshwater body, the Vellayani Lake on land property prices surrounding it. The results revealed that the marginal implicit price of getting one cent of land with lake view evaluated at mean property price of Rs. 2,44250 was Rs.79171. The total aesthetic value of land with the scenic beauty of the lake was Rs. 275.92 crores.


Author(s):  
S.E. Rudov ◽  
◽  
V.Ya. Shapiro ◽  
O.I. Grigoreva ◽  
I.V. Grigorev ◽  
...  

In the Russian Federation logging operations are traditionally carried out in winter. This is due to the predominance of areas with swamped and water-logged (class III and IV) soils in the forest fund, where work of forestry equipment is difficult, and sometimes impossible in the warm season. The work of logging companies in the forests of the cryolithozone, characterized by a sharply continental climate, with severe frosts in winter, is hampered by the fact that forest machines are not recommended to operate at temperatures below –40 °C due to the high probability of breaking of metal structures and hydraulic system. At the same time, in the warm season, most of the cutting areas on cryosolic soils become difficult to pass for heavy forest machines. It turns out that the convenient period for logging in the forests of the cryolithozone is quite small. This results in the need of work in the so-called off-season period, when the air temperature becomes positive, and the thawing processes of the soil top layer begin. The same applies to the logging companies not operating in the conditions of cryosolic soils, for instance, in the Leningrad, Novgorod, Pskov, Vologda regions, etc. The observed climate warming has led to a significant reduction in the sustained period of winter logging. Frequent temperature transitions around 0 °C in winter, autumn and spring necessitate to work during the off-season too, while cutting areas thaw. In bad seasonal and climatic conditions, which primarily include off-season periods in general and permafrost in particular, it is very difficult to take into account in mathematical models features of soil freezing and thawing and their effect on the destruction nature. The article shows that the development of long-term predictive models of indicators of cyclic interaction between the skidding system and forest soil in adverse climatic conditions of off-season logging operations in order to improve their reliability requires rapid adjustment of the calculated parameters based on the actual experimental data at a given step of the cycles.


1993 ◽  
Vol 28 (1) ◽  
pp. 83-110 ◽  
Author(s):  
Richard E. Farrell ◽  
Jae E. Yang ◽  
P. Ming Huang ◽  
Wen K. Liaw

Abstract Porewater samples from the upper Qu’Appelle River basin in Saskatchewan, Canada, were analyzed to obtain metal, inorganic ligand and amino add profiles. These data were used to compute the aqueous speciation of the metals in each porewater using the computer program GEOCHEM-PC. The porewaters were classified as slightly to moderately saline. Metal concentrations reflected both the geology of the drainage basin and the impact of anthropogenic activities. Whereas K and Na were present almost entirely as the free aquo ions, carbonate equilibria dominated the speciation of Ca. Mg and Mn (the predominant metal ligand species were of the type MCO3 (s). MCO30. and MHCO3+). Trace metal concentrations were generally within the ranges reported for non-polluted freshwater systems. Whereas the speciation of the trace metals Cr(III) and Co(II) was dominated by carbonate equilibria, Hg(II)-, Zn(II)- and Fe(II)-speciation was dominated by hydroxy-metal complexes of the type M(OH)+ and M(OH)2°. The speciation of Fe(III) was dominated by Fe(OH)3 (s). In porewaters with high chloride concentrations (&gt; 2 mM), however, significant amounts of Hg(II) were bound as HgCl20 and HgClOH0. The aqueous speciation of Al was dominated by Al(OH)4− and Al2Si2O4(OH)6 (s). Total concentrations of dissolved free amino acids varied from 15.21 to 25.17 umole L−1. The most important metal scavenging amino acids were histidine (due to high stability constants for the metal-histidine complexes) and tryptophan (due to its relatively high concentration in the porewaters. i.e., 5.96 to 7.73 umole L−1). Secondary concentrations of various trace metal-amino add complexes were computed for all the porewaters, but metal-amino acid complexes dominated the speciation of Cu(II) in all the porewaters and Ni(II) in two of the porewaters.


Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3746
Author(s):  
Magdalena Polak-Śliwińska ◽  
Małgorzata Tańska

The benefits of natural honeybee products (e.g., honey, royal jelly, beeswax, propolis, beevenom and pollen) to the immune system are remarkable, and many of them are involved in the induction of antibody production, maturation of immune cells and stimulation of the immune system. The type of plants in the geographical area, climatic conditions and production method have a significantly influence on the nutritional quality of honey. However, this variability can influence consumer liking by the sensory attributes of the product. The aim of this work was to compare the most popular honeys from Poland in terms of nutritional value, organoleptic properties and antioxidant activity. In the study, five varieties of honey (honeydew, forest, buckwheat, linden and dandelion) from conventional and organic production methods were tested. The nutritional characteristics of honey samples included acidity, content of water, sugars, vitamin C, HMF and phenolics (total and flavonoids), while honey color, taste, aroma and consistency were investigated in the organoleptic characteristics. The antioxidant activity was determined in water- and ethanol-soluble honey extracts using DPPH and ORAC tests. The results showed that organoleptic and nutritional characteristics of popular Polish honeys differ significantly in relation to plant source and production method. The significant effect of honey variety on the content of HMF, saccharose and phenolics, as well as acidity and antioxidant capacity were noted. The impact of variety and variety × production method interaction was significant in the case of the content of vitamin C, glucose and fructose. A visible difference of buckwheat and forest honeys from other samples was observed. The highest content of total phenolics with antioxidant activity based on the SET mechanism was found in buckwheat honeys, while forest honeys were richer in flavonoids.


Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 454
Author(s):  
Andrew R. Jakovlev ◽  
Sergei P. Smyshlyaev ◽  
Vener Y. Galin

The influence of sea-surface temperature (SST) on the lower troposphere and lower stratosphere temperature in the tropical, middle, and polar latitudes is studied for 1980–2019 based on the MERRA2, ERA5, and Met Office reanalysis data, and numerical modeling with a chemistry-climate model (CCM) of the lower and middle atmosphere. The variability of SST is analyzed according to Met Office and ERA5 data, while the variability of atmospheric temperature is investigated according to MERRA2 and ERA5 data. Analysis of sea surface temperature trends based on reanalysis data revealed that a significant positive SST trend of about 0.1 degrees per decade is observed over the globe. In the middle latitudes of the Northern Hemisphere, the trend (about 0.2 degrees per decade) is 2 times higher than the global average, and 5 times higher than in the Southern Hemisphere (about 0.04 degrees per decade). At polar latitudes, opposite SST trends are observed in the Arctic (positive) and Antarctic (negative). The impact of the El Niño Southern Oscillation phenomenon on the temperature of the lower and middle atmosphere in the middle and polar latitudes of the Northern and Southern Hemispheres is discussed. To assess the relative influence of SST, CO2, and other greenhouse gases’ variability on the temperature of the lower troposphere and lower stratosphere, numerical calculations with a CCM were performed for several scenarios of accounting for the SST and carbon dioxide variability. The results of numerical experiments with a CCM demonstrated that the influence of SST prevails in the troposphere, while for the stratosphere, an increase in the CO2 content plays the most important role.


Sign in / Sign up

Export Citation Format

Share Document