Allozymic diversity was studied for proteins encoded by 28 putative loci in 170 plants of wild ba... more Allozymic diversity was studied for proteins encoded by 28 putative loci in 170 plants of wild barley, Hordeum spontaneum, and for 13 loci in 78 different thalli of the lichen Caloplaca aurantia, from the Lower Nahal Oren microsite, Mt. Carmel, Israel, designated by us 'Evolu-tion Canyon'. The samples of wild barley were collected from six stations: three (upper, middle, lower) on the south-facing slope (SF-slope) and three (lower, middle, upper) on the north-facing slope (NF-slope). The samples of C. aurantia were collected from three stations: two (middle and upper) on the SF-slope and one (upper) on the NF-slope. Higher solar radiation on the SF-than on the NF-slope makes it warmer, drier, spatiotemporally more heterogeneous, and climatically more fluctuating and stressful. Consequently, it exhibits an open park forest representing an 'African' savanna landscape. Significant inter-and intraslope allozymic differentiation was found in both organisms with generally higher polymorphism, heterozygosity, allele and gene diversity on the more variable and stressful upper station of the SF-slope, as expected by the niche-width variation hypothesis, and the environmental theory of genetic diversity. Solar radiation, temperature and aridity stress caused intersiope and intra-slope differences on the SF-slope in genotypes and phenotypes of wild barley and the lichen at the 'Evolution Canyon' microsite, as was the case for beetles, diplopods and earthworms tested at the site. Diversifying natural (microclimatic) selection appears to be the major evolutionary driving force causing interslope and SF-intraslope adaptative genetic divergence. 'Evolution Canyon' proves an optimal model for unravelling evolution in action, across life and organizational levels.
Lichens are considered the result of a symbiotic association of a fungus and an alga. More precis... more Lichens are considered the result of a symbiotic association of a fungus and an alga. More precisely the term "alga" indicates either a Cyanobacteriae or a Chlorophyceae; the fungus is usually an Ascomycetes, although on rare occasions it may be either a Basidiomycetes or a Phycomycetes. In this association, the alga is the part that is occupied with the formation of nutrients, since it contains chlorophyll (Chl), while the fungus supplies the alga with water and minerals. These organisms are perennial and maintain a uniform morphology over time. They grow slowly, have a large-scale dependence upon the environment for their nutrition, and-differently from vascular plants-they do not shed parts during growth. Furthermore, their lack of cuticle or stoma means that the different contaminants are absorbed over the entire surface of the organism [1-3]. As far back as 1866, a study was published on epiphytic lichens used as bioindicators [4]. Lichens are the most studied bioindicators of air quality [5]. They have been defined as "permanent control systems" for air pollution assessment [6]. During the last 30 years, many studies have stressed the possibility of using lichens as biomonitors of air quality in view of their sensitivity to various environmental factors, which can provoke changes in some of their components and/or specific parameters [3, 7-30]. For indeed, many physiological parameters are used to evaluate environmental damage to lichens, such as: photosynthesis [31-33]; chlorophyll content and degradation [34-37]; decrease of ATP; variations in respiration levels [34]; changes in the level of endogenous auxins; and ethylene production [38-40]. Furthermore, laboratory exposure to SO 2 causes relevant membrane damage to lichen cells [41]. Many studies show a positive correlation between the sulphur content of lichens and SO 2 present in the atmosphere [42-45]. Various authors report that the concentration of Chl a + b is altered by vehicle traffic pollution [46-48], and by urban emissions [49]. In general, lichens that are transplanted into areas with intense vehicle traffic show an increase in Chl a + b concentration that is proportional to increases in emissions. Such effects are
Environmental and Experimental Botany, Jul 1, 1992
Lichen thalli were soaked in water adjusted to pH 1.0 12.0 to stud? the influence of different pH... more Lichen thalli were soaked in water adjusted to pH 1.0 12.0 to stud? the influence of different pH conditions on the integrity of the photohiont's chlorophyll. The ratio OD 435 nm/OD 415 nm, used to estimate the chlorophyll degradation, decreased aftcr a 30 rain treatment in water acidified to pH 1.0 2,0. Thalli were exposed to solutions containing potassimn or heavy metal chlorides, sultktes and nitrates under acidic conditions, all of which excrted different degrees of chlorophyll damage. The chlorophyU integrity was espccially affected lbllowing treatment of the thalli with Cu, Zn, Mn, Pb, Fe(II) and Fe{.III) salts under pH 2.0. Under the same pH, SO~-comhined with K + proved more harnfful to the photohiont chlorophyll than C1 anions. After a treatment with CuC1.,, a very low OD 435 nm/OD 415 nm ratio was obtained.
Environmental and Experimental Botany, Oct 1, 1993
Temporal and spatial fluctuations of ethylene production and the concentrations of sulfur, sodium... more Temporal and spatial fluctuations of ethylene production and the concentrations of sulfur, sodium, chlorine and iron on/in the thallus cortex in the lichen Ramalina duriaei (De Not.) Bagl. ENVIRONMENTAL AND EXPERIMENTAL BOTANY 33, 553-563, 1993. ~ Thalli of the lichen Ramalina duriaei (De Not.) Bagl., growing on carob twigs, were taken from an unpolluted forest area and transplanted within the original forest and to an industrial area in Northwest Israel. The production of ethylene by transplanted and nontransplanted lichen thalli left in the original forest and by transplanted thalli in the industrial area was measured after various periods of exposure of the thalli to their surroundings. Lichens produced larger amounts of ethylene in the polluted industrial sites than in the control site within their original unpolluted forest area. Changes in the production of ethylene were observed rather quickly under certain pollution conditions. Temporal and spatial fluctuations in the production of ethylene of a sensitive lichen, rather than the absolute amounts of ethylene produced by transplanted thalli, were deemed to reflect environmental stress in the lichen and were used as a bioindicator of air pollution. Thalli retrieved in the vicinity of a steel smelter bore on/in their cortex large amounts of S and Fe, as detected with a scanning electron microscope (SEM) combined with energy dispersive X-ray analysis (EDX). Such thalli also showed large amounts of Na and C1 on/in the cortex. Probable correlations between fluctuations in ethylene production by lichens and environmental factors are discussed.
Archives of Environmental Contamination and Toxicology, Sep 1, 1988
... changes in the quality of the air in the region of a new coal-fired power station, the ... Su... more ... changes in the quality of the air in the region of a new coal-fired power station, the ... Such damage, which affects in different ways the integrity of ATP in the whole organism, are ... Assessment of all the data referring to the lichen material, ie, its heavy metals content, its chloro-phyll ...
The microclimate of the cryptoendolithic lichen habitat was studied on Linnaeus Terrace (1,600-1,... more The microclimate of the cryptoendolithic lichen habitat was studied on Linnaeus Terrace (1,600-1,650 m alt.) in the mountainous region of the Antarctic dry valleys between Nov. 30 and Dec. 11, 1979. Three types of weather conditions occurred: 1) overcast, with periods of fog and snow, 2a) clear and windy, and 2b) clear with no winds. Air temperature was consistently below-6 DC. Relative humidity rose to 74% on an overcast day, but was lower (16-47%) on clear days. The northern face of sandstone rocks, mostly exposed to the sun, is colonized by lichens, while the southern, shaded face is free of lichens. Temperature of rocks with a southern exposure remained at all times below 0 DC. For rock surfaces exposed to the north, temperatures rose to 7 DC on clear days, but remained below 0 DC on overcast days. On a windy day, mean rock temperatures were significantly lower. Heat gradients were recorded in the upper 15 mm of the rock substrate. Photosynthetically active solar radiation at the rock surface amounted to over I,OOO,uE m-2 S-1 on an overcast day and to about 1,500 ,uE m-2 S-1 on clear days. Approximately 1 % of incident light penetrates the rock to the level of the lichens. Relative humidity inside the rock was generally high and remained at 80 % or more for 5 days following snowfall. Meltwater entering the porous rocks is a water reservoir for the lichens. Measurements on rock samples collected in earlier years at Linnaeus Terrace indicated that the water content of rocks may not stay high at all times. Steep or vertical rock faces where snow cannot accumulate are dry and are not colonized by lichens. Water loss (evaporation) from the rock surface is of the same order of magnitude as that from an open water-saturated system. The results show that both temperature and humidity conditions are significantly more favorable for the life in the lichen zone inside the rock than on the surface. It was estimated tentatively that, on an overcast day, cryptoendolithic lichens may have been photosynthetically active for about 15 h, although these conditions were suboptimal. On a clear and windy day, photosynthesis may have been possible for 11 h, with 4 h optimal activity. On a clear, warm and calm day, the estimates amounted to 13.5 and 6.5 h, respectively. 1) The term "dry valleys" is used in this paper to denote the entire mountain region rather than the valley bottoms only.
Environmental Pollution Series A, Ecological and Biological, 1985
Thalli of the fruticose lichen Ramalina duriaei (De Not.) Jatta collected at a rural unpolluted a... more Thalli of the fruticose lichen Ramalina duriaei (De Not.) Jatta collected at a rural unpolluted area were coated with synthetic coating polymers. The coated lichens were transplanted to a polluted site near a busy road intersection, for a period of 5 months. After the exposure period the content of Cu, Pb, and Ni in the thalli was measured. It was found that some of the coating polymers were effective in reducing the accumulation of Cu and Ni in the lichen thallus, but could not prevent the penetration of Pb. The coating treatment reduced chlorophyll degradation which occurred in the uncoated lichens.
Environmental and Experimental Botany, Jul 1, 1991
Localization of iron and other elements in the lichen Nephroma arcticum collected in Sweden (Abis... more Localization of iron and other elements in the lichen Nephroma arcticum collected in Sweden (Abisko, N Lapland) was studied under acidic conditions after thalli had been soaked in a 20 mM FeC12 solution. Twelve elements accumulating in different parts of the thallus were detected via an SEM linked to an energy dispersive X-ray analysis unit. There were no significant differences in Na and A1 amounts between the control arid the FeCl~-treated samples. The percentages of Fe in apothecial discs, ascospores, necks of apothecia and in thalli of treated samples were higher than in control samples but the percentages in the dorsal part of the discs were similar in the treated and control thalli. The percentage of CI was higher in all five parts of the lichen samples treated with FeC12. Lower percentages of K, Ca and Mg were detected in those parts of the treated lichen in which high elevations of Fe and C1 were tbund. The ratio between "net" percentage of C1 and Fe atoms in discs and in ascospores was tbund to be closest to the 2.00 value, which occurs in the FeC12 tbrmula. The accumulation of these two elements, coupled to the leakage of essential ions from lichen discs and ascospores, appears to be deleterious to lichen mycobiont reproductive capacity.
Free-living cells of a green alga were found on pitted surfaces of old concrete tiles. Ascospores... more Free-living cells of a green alga were found on pitted surfaces of old concrete tiles. Ascospores of the epilithic crustose lichens Lecanora dispersa, Protoblastenia immersa, Candelariella aurella, and Caloplaca aurantia, which colonize this substrate, were found in the same microniches as the algal cells. Free ascospores of these lichens were found in groups of seven or eight and it is suggested, therefore, that under natural conditions these ascospores are liberated from the lichen asci in clusters of eight. Contacts between free-living algal cells and germinating ascospores of the lichens Lecanora dispersa and Caloplaca aurantia were also observed.
Large parts of the Middle Eastern countries (Egypt, Israel, Lebanon, Syria, Jordan, Iraq, Saudi A... more Large parts of the Middle Eastern countries (Egypt, Israel, Lebanon, Syria, Jordan, Iraq, Saudi Arabia, Kuwait) are arid and semiarid regions, and thus are characterized by limited higher plant cover. These areas are often densely covered by communities of cyanobacteria, green algae, fungi, lichens, and mosses which form typical biological soil crusts. The information available on these crusts for the
analysis revealed negative correlations between F v /F m ratios To determine the environmental im... more analysis revealed negative correlations between F v /F m ratios To determine the environmental impact of industrial activity, we examined and compared the following parameters of phys-and Ba contents of transplants. High Ba, Cu, Ni and Zn contents correlated negatively with NDVI values. NDVI val-iological integrity in the epiphytic fruticose lichen Ramalina ues correlated with A 435nm /A 415nm , F v /F m and K. The ratio lacera. (1) Potential quantum yield of PSII expressed as the chlorophyll fluorescence ratio F v /F m. (2) Spectral reflectance A 435nm /A 415nm correlated positively with K and negatively with Ba, Cu and Zn. The production of ethylene correlated posi-expressed as values of normalized difference vegetation index tively with Cu and Ba and negatively with A 435nm /A 415nm , (NDVI). (3) Production of ethylene. (4) Electrolyte leakage brought about by degrading cell membranes in terms of F v /F m and NDVI. Electric conductivity values correlated positively with Ba, Cu, Na, S, V and Zn and negatively with electric conductivity. (5) The ratio A 435nm /A 415nm indicating NDVI. Both elemental content and physiological alterations in the disintegration of chlorophyll. The amounts of Ba, Cu, K, Ni, S, V and Zn contained in the lichen thallus were measured transplants of R. lacera point to a high degree of contaminato quantify the degree of pollution. Some of the lichen-carry-tion in the Haifa Bay region, which is polluted by fuel-oil ing twigs collected at a relatively unpolluted control site were combustion apart from other industrial activities. The present resuspended on the original trees as controls. Other lichens work suggests that in our specific study area, the most sensitive parameter to assess the vitality of the lichen thallus is were transplanted to 19 biomonitoring sites. Transplanted lichens in polluted sites contained higher amounts of Ba, Ni, electric conductivity whereas ethylene production is less sensitive. S, V and Zn than lichens in the control site and in most of the rural sites upon an exposure period of 8 months. Statistical
Allozymic diversity was studied for proteins encoded by 28 putative loci in 170 plants of wild ba... more Allozymic diversity was studied for proteins encoded by 28 putative loci in 170 plants of wild barley, Hordeum spontaneum, and for 13 loci in 78 different thalli of the lichen Caloplaca aurantia, from the Lower Nahal Oren microsite, Mt. Carmel, Israel, designated by us 'Evolu-tion Canyon'. The samples of wild barley were collected from six stations: three (upper, middle, lower) on the south-facing slope (SF-slope) and three (lower, middle, upper) on the north-facing slope (NF-slope). The samples of C. aurantia were collected from three stations: two (middle and upper) on the SF-slope and one (upper) on the NF-slope. Higher solar radiation on the SF-than on the NF-slope makes it warmer, drier, spatiotemporally more heterogeneous, and climatically more fluctuating and stressful. Consequently, it exhibits an open park forest representing an 'African' savanna landscape. Significant inter-and intraslope allozymic differentiation was found in both organisms with generally higher polymorphism, heterozygosity, allele and gene diversity on the more variable and stressful upper station of the SF-slope, as expected by the niche-width variation hypothesis, and the environmental theory of genetic diversity. Solar radiation, temperature and aridity stress caused intersiope and intra-slope differences on the SF-slope in genotypes and phenotypes of wild barley and the lichen at the 'Evolution Canyon' microsite, as was the case for beetles, diplopods and earthworms tested at the site. Diversifying natural (microclimatic) selection appears to be the major evolutionary driving force causing interslope and SF-intraslope adaptative genetic divergence. 'Evolution Canyon' proves an optimal model for unravelling evolution in action, across life and organizational levels.
Lichens are considered the result of a symbiotic association of a fungus and an alga. More precis... more Lichens are considered the result of a symbiotic association of a fungus and an alga. More precisely the term "alga" indicates either a Cyanobacteriae or a Chlorophyceae; the fungus is usually an Ascomycetes, although on rare occasions it may be either a Basidiomycetes or a Phycomycetes. In this association, the alga is the part that is occupied with the formation of nutrients, since it contains chlorophyll (Chl), while the fungus supplies the alga with water and minerals. These organisms are perennial and maintain a uniform morphology over time. They grow slowly, have a large-scale dependence upon the environment for their nutrition, and-differently from vascular plants-they do not shed parts during growth. Furthermore, their lack of cuticle or stoma means that the different contaminants are absorbed over the entire surface of the organism [1-3]. As far back as 1866, a study was published on epiphytic lichens used as bioindicators [4]. Lichens are the most studied bioindicators of air quality [5]. They have been defined as "permanent control systems" for air pollution assessment [6]. During the last 30 years, many studies have stressed the possibility of using lichens as biomonitors of air quality in view of their sensitivity to various environmental factors, which can provoke changes in some of their components and/or specific parameters [3, 7-30]. For indeed, many physiological parameters are used to evaluate environmental damage to lichens, such as: photosynthesis [31-33]; chlorophyll content and degradation [34-37]; decrease of ATP; variations in respiration levels [34]; changes in the level of endogenous auxins; and ethylene production [38-40]. Furthermore, laboratory exposure to SO 2 causes relevant membrane damage to lichen cells [41]. Many studies show a positive correlation between the sulphur content of lichens and SO 2 present in the atmosphere [42-45]. Various authors report that the concentration of Chl a + b is altered by vehicle traffic pollution [46-48], and by urban emissions [49]. In general, lichens that are transplanted into areas with intense vehicle traffic show an increase in Chl a + b concentration that is proportional to increases in emissions. Such effects are
Environmental and Experimental Botany, Jul 1, 1992
Lichen thalli were soaked in water adjusted to pH 1.0 12.0 to stud? the influence of different pH... more Lichen thalli were soaked in water adjusted to pH 1.0 12.0 to stud? the influence of different pH conditions on the integrity of the photohiont's chlorophyll. The ratio OD 435 nm/OD 415 nm, used to estimate the chlorophyll degradation, decreased aftcr a 30 rain treatment in water acidified to pH 1.0 2,0. Thalli were exposed to solutions containing potassimn or heavy metal chlorides, sultktes and nitrates under acidic conditions, all of which excrted different degrees of chlorophyll damage. The chlorophyU integrity was espccially affected lbllowing treatment of the thalli with Cu, Zn, Mn, Pb, Fe(II) and Fe{.III) salts under pH 2.0. Under the same pH, SO~-comhined with K + proved more harnfful to the photohiont chlorophyll than C1 anions. After a treatment with CuC1.,, a very low OD 435 nm/OD 415 nm ratio was obtained.
Environmental and Experimental Botany, Oct 1, 1993
Temporal and spatial fluctuations of ethylene production and the concentrations of sulfur, sodium... more Temporal and spatial fluctuations of ethylene production and the concentrations of sulfur, sodium, chlorine and iron on/in the thallus cortex in the lichen Ramalina duriaei (De Not.) Bagl. ENVIRONMENTAL AND EXPERIMENTAL BOTANY 33, 553-563, 1993. ~ Thalli of the lichen Ramalina duriaei (De Not.) Bagl., growing on carob twigs, were taken from an unpolluted forest area and transplanted within the original forest and to an industrial area in Northwest Israel. The production of ethylene by transplanted and nontransplanted lichen thalli left in the original forest and by transplanted thalli in the industrial area was measured after various periods of exposure of the thalli to their surroundings. Lichens produced larger amounts of ethylene in the polluted industrial sites than in the control site within their original unpolluted forest area. Changes in the production of ethylene were observed rather quickly under certain pollution conditions. Temporal and spatial fluctuations in the production of ethylene of a sensitive lichen, rather than the absolute amounts of ethylene produced by transplanted thalli, were deemed to reflect environmental stress in the lichen and were used as a bioindicator of air pollution. Thalli retrieved in the vicinity of a steel smelter bore on/in their cortex large amounts of S and Fe, as detected with a scanning electron microscope (SEM) combined with energy dispersive X-ray analysis (EDX). Such thalli also showed large amounts of Na and C1 on/in the cortex. Probable correlations between fluctuations in ethylene production by lichens and environmental factors are discussed.
Archives of Environmental Contamination and Toxicology, Sep 1, 1988
... changes in the quality of the air in the region of a new coal-fired power station, the ... Su... more ... changes in the quality of the air in the region of a new coal-fired power station, the ... Such damage, which affects in different ways the integrity of ATP in the whole organism, are ... Assessment of all the data referring to the lichen material, ie, its heavy metals content, its chloro-phyll ...
The microclimate of the cryptoendolithic lichen habitat was studied on Linnaeus Terrace (1,600-1,... more The microclimate of the cryptoendolithic lichen habitat was studied on Linnaeus Terrace (1,600-1,650 m alt.) in the mountainous region of the Antarctic dry valleys between Nov. 30 and Dec. 11, 1979. Three types of weather conditions occurred: 1) overcast, with periods of fog and snow, 2a) clear and windy, and 2b) clear with no winds. Air temperature was consistently below-6 DC. Relative humidity rose to 74% on an overcast day, but was lower (16-47%) on clear days. The northern face of sandstone rocks, mostly exposed to the sun, is colonized by lichens, while the southern, shaded face is free of lichens. Temperature of rocks with a southern exposure remained at all times below 0 DC. For rock surfaces exposed to the north, temperatures rose to 7 DC on clear days, but remained below 0 DC on overcast days. On a windy day, mean rock temperatures were significantly lower. Heat gradients were recorded in the upper 15 mm of the rock substrate. Photosynthetically active solar radiation at the rock surface amounted to over I,OOO,uE m-2 S-1 on an overcast day and to about 1,500 ,uE m-2 S-1 on clear days. Approximately 1 % of incident light penetrates the rock to the level of the lichens. Relative humidity inside the rock was generally high and remained at 80 % or more for 5 days following snowfall. Meltwater entering the porous rocks is a water reservoir for the lichens. Measurements on rock samples collected in earlier years at Linnaeus Terrace indicated that the water content of rocks may not stay high at all times. Steep or vertical rock faces where snow cannot accumulate are dry and are not colonized by lichens. Water loss (evaporation) from the rock surface is of the same order of magnitude as that from an open water-saturated system. The results show that both temperature and humidity conditions are significantly more favorable for the life in the lichen zone inside the rock than on the surface. It was estimated tentatively that, on an overcast day, cryptoendolithic lichens may have been photosynthetically active for about 15 h, although these conditions were suboptimal. On a clear and windy day, photosynthesis may have been possible for 11 h, with 4 h optimal activity. On a clear, warm and calm day, the estimates amounted to 13.5 and 6.5 h, respectively. 1) The term "dry valleys" is used in this paper to denote the entire mountain region rather than the valley bottoms only.
Environmental Pollution Series A, Ecological and Biological, 1985
Thalli of the fruticose lichen Ramalina duriaei (De Not.) Jatta collected at a rural unpolluted a... more Thalli of the fruticose lichen Ramalina duriaei (De Not.) Jatta collected at a rural unpolluted area were coated with synthetic coating polymers. The coated lichens were transplanted to a polluted site near a busy road intersection, for a period of 5 months. After the exposure period the content of Cu, Pb, and Ni in the thalli was measured. It was found that some of the coating polymers were effective in reducing the accumulation of Cu and Ni in the lichen thallus, but could not prevent the penetration of Pb. The coating treatment reduced chlorophyll degradation which occurred in the uncoated lichens.
Environmental and Experimental Botany, Jul 1, 1991
Localization of iron and other elements in the lichen Nephroma arcticum collected in Sweden (Abis... more Localization of iron and other elements in the lichen Nephroma arcticum collected in Sweden (Abisko, N Lapland) was studied under acidic conditions after thalli had been soaked in a 20 mM FeC12 solution. Twelve elements accumulating in different parts of the thallus were detected via an SEM linked to an energy dispersive X-ray analysis unit. There were no significant differences in Na and A1 amounts between the control arid the FeCl~-treated samples. The percentages of Fe in apothecial discs, ascospores, necks of apothecia and in thalli of treated samples were higher than in control samples but the percentages in the dorsal part of the discs were similar in the treated and control thalli. The percentage of CI was higher in all five parts of the lichen samples treated with FeC12. Lower percentages of K, Ca and Mg were detected in those parts of the treated lichen in which high elevations of Fe and C1 were tbund. The ratio between "net" percentage of C1 and Fe atoms in discs and in ascospores was tbund to be closest to the 2.00 value, which occurs in the FeC12 tbrmula. The accumulation of these two elements, coupled to the leakage of essential ions from lichen discs and ascospores, appears to be deleterious to lichen mycobiont reproductive capacity.
Free-living cells of a green alga were found on pitted surfaces of old concrete tiles. Ascospores... more Free-living cells of a green alga were found on pitted surfaces of old concrete tiles. Ascospores of the epilithic crustose lichens Lecanora dispersa, Protoblastenia immersa, Candelariella aurella, and Caloplaca aurantia, which colonize this substrate, were found in the same microniches as the algal cells. Free ascospores of these lichens were found in groups of seven or eight and it is suggested, therefore, that under natural conditions these ascospores are liberated from the lichen asci in clusters of eight. Contacts between free-living algal cells and germinating ascospores of the lichens Lecanora dispersa and Caloplaca aurantia were also observed.
Large parts of the Middle Eastern countries (Egypt, Israel, Lebanon, Syria, Jordan, Iraq, Saudi A... more Large parts of the Middle Eastern countries (Egypt, Israel, Lebanon, Syria, Jordan, Iraq, Saudi Arabia, Kuwait) are arid and semiarid regions, and thus are characterized by limited higher plant cover. These areas are often densely covered by communities of cyanobacteria, green algae, fungi, lichens, and mosses which form typical biological soil crusts. The information available on these crusts for the
analysis revealed negative correlations between F v /F m ratios To determine the environmental im... more analysis revealed negative correlations between F v /F m ratios To determine the environmental impact of industrial activity, we examined and compared the following parameters of phys-and Ba contents of transplants. High Ba, Cu, Ni and Zn contents correlated negatively with NDVI values. NDVI val-iological integrity in the epiphytic fruticose lichen Ramalina ues correlated with A 435nm /A 415nm , F v /F m and K. The ratio lacera. (1) Potential quantum yield of PSII expressed as the chlorophyll fluorescence ratio F v /F m. (2) Spectral reflectance A 435nm /A 415nm correlated positively with K and negatively with Ba, Cu and Zn. The production of ethylene correlated posi-expressed as values of normalized difference vegetation index tively with Cu and Ba and negatively with A 435nm /A 415nm , (NDVI). (3) Production of ethylene. (4) Electrolyte leakage brought about by degrading cell membranes in terms of F v /F m and NDVI. Electric conductivity values correlated positively with Ba, Cu, Na, S, V and Zn and negatively with electric conductivity. (5) The ratio A 435nm /A 415nm indicating NDVI. Both elemental content and physiological alterations in the disintegration of chlorophyll. The amounts of Ba, Cu, K, Ni, S, V and Zn contained in the lichen thallus were measured transplants of R. lacera point to a high degree of contaminato quantify the degree of pollution. Some of the lichen-carry-tion in the Haifa Bay region, which is polluted by fuel-oil ing twigs collected at a relatively unpolluted control site were combustion apart from other industrial activities. The present resuspended on the original trees as controls. Other lichens work suggests that in our specific study area, the most sensitive parameter to assess the vitality of the lichen thallus is were transplanted to 19 biomonitoring sites. Transplanted lichens in polluted sites contained higher amounts of Ba, Ni, electric conductivity whereas ethylene production is less sensitive. S, V and Zn than lichens in the control site and in most of the rural sites upon an exposure period of 8 months. Statistical
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Papers by Jacob Garty