人类活动对太湖地区地表水水质的影响

Taihu Lake region is one of the most industrialized areas in China, and the surface water is progressively susceptible to anthropogenic pollution. The physicochemical parameters of surface water quality were determined at 20 sampling sites in Taihu Lake region, China in spring, summer, autumn, and winter seasons of 2005-2006 to assess the effect of human activities on the surface water quality. Principal component analysis (PCA) and cluster analysis (CA) were used to identify characteristics of the water quality in the studied water bodies. PCA extracted the first three principal components (PCs), explaining 80.84% of the total variance of the raw data. Especially, PC1 (38.91%) was associated with NH₄-N, total N, soluble reactive phosphorus, and total P. PC2 (22.70%) was characterized by NO₃-N and temperature. PC3 (19.23%) was mainly associated with pH and dissolved organic carbon. CA showed that streams were influenced by urban residential subsistence and livestock farming contributed significantly to PC1 throughout the year. The streams influenced by farmland runoff contributed most to PC2 in spring and winter compared with other streams. PC3 was affected mainly by aquiculture in spring, rural residential subsistence in summer, and livestock farming in fall and winter seasons. Further analyses showed that farmlands contributed significantly to nitrogen pollution of Taihu Lake, while urban residential subsistence and livestock farming also polluted water quality of Taihu Lake in rainy season. The results would be helpful for the authorities to take sound actions for an effective management of water quality in Taihu Lake region.     

广西沿海红树林区的水鸟

广西沿海地区位于一条重要的候鸟迁徙通道上，那里的红树林区给为数众多的水鸟提供了繁殖、越冬和迁徙中途歇息的场所。在红树林区记录到115种水鸟。这些鸟类中，102种是候鸟，包括13种夏候鸟、64种冬候鸟、25种旅鸟，因此红树林区水鸟类的多样性表现出明显的季节性。迁徙季节水鸟的种类和数量都最多，繁殖季节则最少。黑脸瑟鹭（Platalea minor)是世界上最濒危的鸟类之一，一个越冬种群在该地区红树林中被发现。     

Anthropogenic effects on the physical and chemical properties of subtropical coastal urban soils

We investigated the effects of various anthropogenic factors on urban soil properties in subtropical, coastal Tampa, FL, USA. Specifically, we explored the influence of (i) urbanization as measured by land use, land cover, population density and years since urban development and (ii) socioeconomic conditions as reflected in household income and property values on bulk density (BD) and several key soil chemical properties. Results indicate that Tampa’s urban soils were affected to varying degrees by these factors with chemical properties being more variable than BD. Across land uses significant differences were found for Mehlich‐1 (M1) extractable P, Ca and Na. A similar trend was observed for land‐cover classes, although significant differences were also found for pH and M1‐Cu. Soil properties had no statistically significant relationship with population density. However, time since urbanization did with M1‐P and Na varying significantly across age categories. For our socioeconomic analyses, M1‐K and Mg levels differed significantly by household income while pH, P, Ca and Na values differed significantly by property value. Overall, our findings indicate that despite their inherent heterogeneity, there are identifiable patterns among subtropical coastal urban soil properties. We suggest that a more thorough understanding of these patterns and their drivers is an essential first step towards developing soil management strategies aimed at maintaining environmental quality and ecosystem services in subtropical cities.     

The impact of high speed, high volume traffic axes on brown bears in Slovenia

The Ljubljana-Razdrto highway and the parallel Ljubljana-Trieste railway cut through critical brown bear (Ursus arctos) habitat in south-central Slovenia. These high speed, high volume traffic axes are located close to the main dispersal corridor for bears from the Dinaric Mountain range into the Alps. We analyzed radiotracking data of 15 individual bears that lived within 10 km of the highway, compared transportation related and overall known bear mortality, and analyzed the spatial distribution of bear-vehicle accidents. The highway posed a home range boundary to resident bears, but was not an absolute barrier. Transportation-related mortality was high in the vicinity of the highway and railway, and averaged 31% of the total known local mortality from 1992 to 1999. At present the detrimental impact of transportation routes on the bear population in Slovenia is modest due to the high density of bears and the low density of highways—but new highways are planned or already under construction. Managers have to be aware that, due to bears large home ranges and long dispersal distances, a single highway affects bears from a huge area—emphasizing the importance of international cooperation and a landscape approach in highway planning.     

Effects of anthracene on microbial activities and organic matter decomposition in a Pinus halepensis litter from a Mediterranean coastal area

Due to increasing atmospheric pollution, it has become highly important to investigate how anthropic chronic contaminations may affect ecosystem functioning. To explore the effect of polycyclic aromatic hydrocarbons (PAHs) on indigenous microbial activities, anthracene was used as a model PAH in a mesocosm experiment with Pinus halepensis litter from the Massif of Marseilleveyre (Marseille, France). The effects of anthracene on microbial activities were followed after 1- and 3- month incubations by: Catabolic Level Physiological Profile (CLPP) using ECO and FF plates and four enzyme activities (cellulase, β-glucosidase, acid phosphatase and lipase). Moreover the chemical variations in organic matter were evaluated by solid-state ¹³C NMR and C/N ratio. These experiments revealed an increase in cellulase, β-glucosidase and phosphatase activities and a decrease in lipase activities after a 3-month incubation in the presence of anthracene. Principal Component Analysis (PCA) from CLPP showed that bacterial catabolic diversity is more influenced than that of fungal communities by anthracene. Correlation between both chemical and biological indicators revealed that the increase in lignocellulolytic enzymes (cellulase, laccase and β-glucosidase) was significantly correlated to the decrease in phenolic compounds. In addition, aromaticity ratio also decreased in the presence of anthracene suggesting that transformation of the recalcitrant part of organic matter was enhanced. Our results highlight the difference in sensitivity of bacterial and fungal communities to PAHs, the later especially active while exposed to high concentrations of pollutant. This suggests that microbial communities inhabiting P. halepensis litters in Mediterranean coastal areas may resist to chronic pollution involving PAH.     

Perceptions of environmental change in a tropical coastal wetland

To assess whether local knowledge can contribute to the identification and evaluation of natural and anthropogenic disturbances in a mangrove forest, interviews were conducted with local fisherman of the Teacapán‐Agua Brava lagoon–estuarine system of Mexico. The results indicate that an increase in water salinity, following the opening of an artificial canal, has resulted in a major disturbance in the mangroves of this region. Observations of changes in the fauna of the mangroves also coincide with this modification. The responses of the fishermen further suggest that the degree of impact from the salinity on the mangroves varies by species (e.g. Laguncularia racemosa is less tolerant than Rhizophora mangle). Other factors identified as inciting disturbances, but not previously reported for this system, include a hurricane and an infestation by caterpillars. According to the fishermen, the continued modification of the water salinity and hurricanes are the two greatest threats to the remaining mangroves. Copyright © 2000 John Wiley & Sons, Ltd.     

Historical morphogenesis of the Turia River coastal flood plain in the Mediterranean littoral of Spain

The cross-referencing of sedimentological, stratigraphic, geoarchaeological and radiocarbon data enables us to establish the geomorphologic evolution of the Late Holocene coastal flood plain of the Turia River. The Holocene marine transgression formed a coastal barrier lagoon environment in the coastal plain. During the Late Holocene, increased sediments supplied to the low reach of the river promoted: (a): the progradation of deltaic coastal sandy ridges on the coastline and (b): the aggradation of the floodplain on top of the sedimentary sequence. Four phases are clearly recognised in the geoarchaeological record of the flood plain. (1): High magnitude flooding events (2800 BP to 3rd century BC). (2): Slow riverbed aggradation and progressive levee formation (low energy flood regime) in Roman times (2nd century BC to 5th century AD). (3): Swampy environmental processes (6th to 9th centuries). (4): Second high-magnitude flooding phase (11th century). The navigable channel of the Roman and early Islamic periods became a wide and shallow braided channel in Medieval times. These phases are correlated with others detected by researchers in many areas of the Mediterranean region and with global Holocene climate events.     

Human impact in the Holocene fluvial and coastal evolution of the Marche region, Central Italy

Today, the coasts of the Marche region are represented by almost continuous rectilinea sand beaches except in the north, at the border with the Romagna region, and in the central part, around the Conero ridge, where there are active rock cliffs. The sandy coasts are protected almost everywhere by artificial barriers built up as a protection against the general tendency to retreat. Along some tracts, the coastal erosion started at the beginning of this century but became generalized after 1940–1950. This was mainly due, first, to the reduction in sediment supply, following the improvement in agricultural techniques after the Italian Unification, and, later, to the widespread extraction of gravels from the thalwegs related to the rapid increase in urban population in the 1950s. However, in the same period, along the rivers, there was a widespread creation of artificial levees to prevent lateral erosion or flooding and to extend areas suitable for agriculture. Following these practices, the lower-middle tracts of the rivers underwent a strong vertical downcutting which increased as a result of the creation of checkdams downvalley of many bridges which contributed to the store of the sediments in the upper part of the valleys. At present, most of the rivers have an irregular course and are deeply entrenched in the bedrock or inside their own sediments.Up to the beginning of the century, most of the lower tracts of the valleys were characterized by strong aggradation in a braidplain system. This aggradation started as early as the Middle Ages (1100 AD) but increased after the Renaissance as a consequence of a generalized deforestation of the Periadriatic Basin and the following severe soil erosion. In the mean time, the coast underwent a very fast progradation, in some places more than 500 m. Small deltas were created at the mouths of the rivers, and longshore bars and sandy beaches began to occupy the base of the active cliffs which previously extended between one river and another. However, in the mountain parts of the river basins, a meander course existed, and in many cases still exists, expecially where the human interventions were of limited extent.Before 1000–1100 AD, all the rivers had a meander pattern and, at the junction with the sea, entered lagoons and swamps in most cases protected by littoral barrier beaches. These conditions were established earlier than the third century BC and have been attributed to the first systematic land clearance and the following soil erosion during the Bronze and Iron Ages. At that time, the regional coastline became almost rectilinear but with many active cliffs between one river and another.Before being affected by a major human impact (earlier than 4000 years BP) the ‘natural’ coastal environment was represented by active rock cliffs which alternated with pocket beaches corresponding to a river mouth. In some rivers, embayments and beaches were located up to 4–5 km inland from the present-day position. After the Flandrian transgression the evidence presented reveals major changes that can be attributed to human impact.     

Natural and Anthropogenic Contributions to PM10 and PM2.5 in an Urban Area in the Western Mediterranean Coast

Source apportionment analysis was used to identify the factors contributing to atmospheric pollution at a monitoring location in the Southeast of Spain, a well documented area with an arid climate and high insolation favouring two sources of particulate matter: secondary transformation in the atmosphere and resuspension of crustal dry soils to the air. These conditions are further complicated by numerous industrial facilities in the area of the historical city of Cartagena. This paper describes the air quality of an area which includes a zinc metallurgical industry, a petrochemical factory, an oil power station, a shipyard and natural phenomena including African dust transport and resuspension of regional and/or local crustal materials. Major and trace element concentrations in PM10 and PM2.5 were determined at two monitoring stations in Cartagena (one PM10 sampler located at a traffic hotspot and the PM2.5 sampler at a suburban station), during 2004 and 2005. Results showed that in the PM10 fraction, the zinc metallurgical activity was linked to high levels of Cd, Zn and Pb; shipyard emission was associated with high levels of Cr and Ni; and high Ni and V levels were associated with the secondary aerosol indicating the contribution from oil combustion (oil-fired power station or petrochemical facilities). In the PM2.5 size fraction, the zinc source is defined by Zn and Pb; V, Ni and As appear with the oil combustion emissions. In contrast to PM10, shipyard activity is not consistently defined. Consistent sources found in both size fractions include crustal materials and traffic emissions.     

Classifying land cover conversions in coastal wetlands in the Mediterranean: Pairwise comparisons of landsat images

This study classified land cover conversions by using quantitative change detection methods in the eastern Mediterranean coastal wetlands of Turkey. Three Landsat TM scenes acquired in 1984, 1998 and 2007 were analysed using image pairs of consecutive dates. The amounts of change were calculated for the periods from 1984 to 1998 and from 1998 to 2007, using binary change masks and supervised image classifications, in which eleven a priori defined land cover classes were used. Change areas accounted for 14.81 and 15.64 per cent of the total area, in the first and second periods, respectively. Conversions from/to sand dunes, mud flats and afforestation were by far the most extensive changes. Sand dunes and mud flats decreased, while afforestation and agriculture areas increased in the 23‐year period between 1984 and 2007. Five types of qualitative change were identified on the basis of land cover transformations within and between natural and anthropogenic systems. Type I changes, which indicated conversions from (semi)natural to anthropogenic systems, took place as agricultural expansion over coastal sand dunes, while Type II changes mostly occurred within agricultural systems. Type III changes included changes in human uses, leading to conversions from one anthropogenic system to another. Conversions between semi(natural) systems such as salt marshes and mud‐flats were typical Type IV changes. Type V changes were mainly due to conversions from agriculture to wetland categories or other semi(natural) cover types. Implications of these changes were discussed for management of coastal environmental resources. Copyright © 2011 John Wiley & Sons, Ltd.     

Yield responses of cauliflower (Brassica oleracea L. var. Botrytis) to different water and nitrogen levels in a Mediterranean coastal area

Abstract

Global warming along with the increasing population and fresh water shortages necessitates a specific fertilization programme under water-scarce conditions. This study was conducted to investigate the effects of different irrigation and nitrogen levels on yield, growth components and water use characteristics of cauliflower (Brassica oleracea L. var. Botrytis cv. Tetris-F1) cultivated in a field for three consecutive years from 2005 to 2007 in the Eastern Mediterranean region of Turkey. Four irrigation (Kcp) levels with a drip irrigation system based on adjustment coefficients (0, 0.75, 1.0 and 1.25) of pan evaporation were used. Nitrogen (N) treatments were consisted of four different nitrogen rates (0, 75, 150 and 225 kg N ha^–1). The following yield and quality parameters were determined: curd weight, curd diameters, number of leaves per crop, above ground biomass (AGB) and curd/AGB ratio. Fertilizer use efficiency (FUE) and leaf mineral contents were also determined to clarify the productivity of N treatments. According to the results; the amount of irrigation water and/or total received water affects the plant water consumption, consequently, crop yield in a field grown cauliflower. The highest yield was obtained in Kcp1.0 irrigation level which represents full irrigation treatment. The excess water applications had negative effect on yield and AGB of cauliflower. Highest yield was obtained at 225 kg N ha^–1.

The water use efficiency and irrigation water use efficiency values increased with decreasing irrigation rate. However, lower Kcp coefficients resulted in lower total yield. The FUE in irrigation treatments showed linear increases from non irrigation to full irrigation plots. However, excessive irrigation caused a decrease in FUE. It can be recommended that the Kcp1.0 crop-pan coefficient with 225 kg ha^–1 nitrogen application can be used to achieve the highest yield for field grown cauliflower in the Eastern Mediterranean coastal region of Turkey.     

木霉制剂改良滨海盐渍土台田生态效应

生物改良滨海盐渍土是一种投资少、需时短、见效快、长期受益的环保生态型技术。通过田间试验将木霉制剂[活性成分为木霉分生孢子,1×107(CFU)·g~(-1)]施用到滨海中度盐渍土台田(含盐量2.99 g·kg~(-1),砂壤土),对土壤改良台田试验区不同处理(施用木霉制剂和常规对照处理)及辅助试验区日光温室(含盐量0.98 g·kg~(-1),壤土)、滨海轻度盐渍土开垦田(含盐量1.75 g·kg-1,轻壤土)、滨海重度盐渍土河滩地(含盐量26.19 g·kg~(-1),砂壤土)的耕层土壤取样室内测定,探究木霉在滨海中度盐渍土台田施用的生态效应。滨海中度盐渍土台田木霉处理与对照处理相比,土壤紧实度提高177.04%,土壤水稳性团聚体数量(≥0.25 mm)提高265.78%,土壤含水率提高320.83%,土壤碱解氮、有效磷、速效钾和有机质含量分别提高96.14%、42.17%、105.65%和63.79%;土壤稀释法培养微生物,细菌、放线菌、真菌、固氮菌数量比对照分别提高170.95%、82.68%、152.17%和471.93%。滨海中度盐渍土台田木霉处理与滨海重度盐渍土河滩地比较,有利于植物生长的指标土壤紧实度、水稳性团聚体、有机质和微生物群落数量分别提高1.53倍、2.11倍、3.20倍和28.33倍,不利植物生长的水溶性盐下降96.60%;滨海中度盐渍土台田通过木霉制剂改良,土壤紧实度、总孔隙度、含水率、有效磷、有机质和微生物数量与滨海轻度盐渍土开垦田相比无显著差异;滨海中度盐渍土台田木霉处理后土壤容重降低、总孔隙度增加,与高产日光温室非盐渍化土壤相比接近。滨海重度盐渍土通过沙土抬高1.2 m筑田变为中度盐渍土,降盐效果较好,再通过加入生物改良措施提高土壤营养和有益微生物,优化土壤团粒结构,利于提高滨海中度盐渍土台田改良效率和质量,促进滨海中度盐渍土台田生态的改善。     

Organic geochemical parameters for estimation of petrogenic inputs in the coastal area of Kavala City,Greece

Background, aims, and scope  Sediments and soils in coastal areas are frequently polluted by anthropogenic contaminants as the result of both riverine or terrestrial discharge and autochthonic marine emissions. In order to determine petrogenic contamination in the coastal industrial area of Kavala City in northern Greece, a combination of polycyclic aromatic hydrocarbon (PAH) and organic geochemical petroleum biomarker analyses has been performed on marine and freshwater sediments as well as soils. Materials and methods  Soils, freshwater, and marine sediments have been treated by standard extraction methods. The dried and desulphurized sample extracts have been fractionated by column chromatography, followed by addition of surrogate standards. Qualitative and quantitative data were obtained by gas chromatograph connected with a flame ionization and electron capture detector (GC-FID/ECD) and by GC linked to a mass spectrometer (GC/MS), whereas identification of compounds was based on EI⁺-mass spectra and gas chromatographic retention times. Quantitative data were obtained by integration of specific ion chromatograms. Results  The total PAH concentrations measured in the area varied highly, showing different levels from 18 up to 318,000 ng g⁻¹ dry weight (dw). Several PAH ratios, as well as the ratio of pristane (Pr) to phytane (Phyt), have been considered. Out of 39 samples, 22 revealed a specific distribution of hopane fingerprints indicating petrogenic input. Finally, in numerous samples, the ratio of 17α(H)-22,29,30-trisnorhopane (Tm) and 18α(H)-22,29,30-trisnorhopane (Ts) was calculated, as well as the ratio of 22S-17α(H),21β(H)-30 homohopane (αβC₃₁-hopane 22S) and 22R-17α(H),21β(H)-30 homohopane (αβC₃₁-hopane 22R). Discussion  Based on the specific PAH ratios, a group of samples was clearly characterized to be contaminated dominantly by combustion-derived emissions, whereas a second group of samples exhibited mixed influence from petrogenic and pyrogenic PAHs. On the other hand, the exhibition of specific hopane fingerprints in many samples indicates a direct petrogenic input. Finally, the values of the ratio of Tm/(Ts + Tm) and of αβC₃₁-hopanes 22S/(22S+22R)-isomer demonstrated an input of highly mature organic matter that has to be clearly attributed to petroleum-derived contamination, while the ratio of Pr/Phyt showed that most samples exhibited an input of organic matter. Conclusions  The coastal area of Kavala is strongly affected by anthropogenic contaminants. Petrogenic emissions were pointed out firstly by PAH analyses that separated dominantly pyrogenic contaminated sites from areas affected by both pyrogenic and petrogenic emissions. However, analyses of organic geochemical biomarkers revealed a much higher sensitivity in identifying petroleum-derived contaminations and were successfully used to differentiate several petrogenic contaminations in the marine and terrestrial samples. Recommendations and perspectives  Based on this study, it was recommended to use a complementary approach of source-specific substances to successfully characterize petrogenic emissions. Generally, a PAH-based source identification of petrogenic versus pyrogenic contaminations should be combined with petroleum biomarker analysis. PAH and biomarker ratios as well as individual biomarker fingerprints revealed a more comprehensive view on the quality and quantity of petrogenic emissions in sediments and soils.     

Land degradation: socioeconomic and environmental causes and consequences in the eastern Mediterranean

Land degradation is a natural and socioeconomic cause–effect phenomenon that is widespread all over the world. This study investigated the socioeconomic factors and causes of land degradation (e.g. population growth and urbanization, poverty, overgrazing, pollution, biodiversity, erosion) in the eastern part of the Mediterranean region. The study revealed a significant land use change from agricultural and natural vegetation to urbanized areas due to the high population increase during the last ca. 80 years (51‐times the magnitude of the total built‐up area). The high poverty rate that exists in the area (57 per cent of the population can be classed as ‘poor’) has resulted in damaging environmental practices (overgrazing and intensive usage of natural plants); we found 83 per cent of the farmers admitted to the adoption of these practices. Poverty has also resulted in an inverse and significant correlation (at the 95 per cent confidence level) between holding size and the sale of land for urban uses. We also noted that 75 per cent of the smallholder farmers surveyed had sold their lands for immediate benefits to cope with poverty. This relation was affected by the education level of the farmers; we found a direct and significant (95 per cent confidence level) correlation existed between these factors. Overgrazing was practised by 70 per cent of the farmers and was found to be one of the most important environmental consequences of land use change (1600 ha have been transformed from natural grazing to built‐up (urban) in the study area). Socio‐economic induced land degradation demands efforts to improve farmer environmental awareness as well as environmental standards, laws and bylaws and the reduction of mismanagement of land. Copyright © 2010 John Wiley & Sons, Ltd.     

Rice cultivation and its environmental conditions in the Mediterranean countries II. Soils,their fertility and mineralogy

In Italy paddy aolls have a broad varfability with respect to region and age of the parent material. The regional characteristics, however, predominate over the age relations, i.e., the Po delta soils have higher potentialities than the youngest of those in the middle reaches of the Po. Among soils of the middle reaches the older the parent material, the more depleted the bases. Some of the better drained terrace soils have the morphology of “aquorizem.”

Spanish paddy soils along the Mediterranean coast are all alike, having an alkaline reaction due to the presence of free lime, and SiCL to SiC textures. Morphologically there are two types of paddy soils, one having gleyed subsoils due to groundwater influence, and the other having brown subsoils below strongly gleyed aurface soils under aubmergence.

Portugese paddy soils are generally similar to Spanish soils both in mode of occurrence and In nature, except for neutral to slightly acidic reaction and absence of free lime in the former.

The general soil potentiality aa judged from chemical and mineralogical atudies is in the order of Spanish>Portugese>Italian paddy aoils.     

Polycyclic aromatic hydrocarbons (PAHs) in marine sediments of the Hellenic coastal zone, eastern Mediterranean: levels, sources and toxicological significance

Purpose  

Polycyclic aromatic hydrocarbons (PAHs) are widespread in sediments, particularly near areas of intense human activities. Due to their mutagenic and carcinogenic behaviour, PAHs are classified as priority contaminants to be monitored in environmental quality control schemes. The purpose of this study was to determine the levels of PAHs in major coastal areas of Greece that receive various pressures, investigate their sources and evaluate their potential toxicity by comparison against effects-based Sediment Quality Guidelines (SQG).     

Soil‐quality‐index model for assessing the impact of groundwater on soil in an intensively farmed coastal area of E China

Soil quality is important in measuring sustainable land‐use and soil‐management practices. It is usually assessed by evaluating important physical, chemical, and biological soil properties. For this study, a site‐specific 22 variables representing pertinent soil (0–10 cm) and groundwater properties were selected as potential soil‐quality indicators in a coastal salt‐affected farmland of E China. To investigate the role of groundwater in soil‐quality assessment, we designed two sets of minimum data sets (MDSs). Minimum data set 1 (MDS1) had inputs of the 19 soil chemical and physical properties whereas MDS2 was based on the 22 soil and groundwater properties. Using principal‐component analysis, discriminant analysis, and soil‐quality‐index (SQI) model, we demonstrated the procedures of MDS selection, indicator normalization, and integration of MDS into SQI value for soils used for the two cropping systems. Results indicated selection of SOCD, AK, and ρ_b as MDS1 indicators but MDS2 indicators included SOM, SOCD, Cl, Na, WT_g, and EC_g. These were found to be the most effective discriminators between the two cropping systems. Available K (AK) made greatest contribution to SQI using MDS1 indicators, however, WT_g, EC_g, and Cl were the greatest contributors to the SQI for MDS2. Contribution of SOCD to SQI was severely inhibited in cotton–barley rotation system while EC_g and WT_g contributions to SQI were inhibited in rice–rape rotation system. In general, cotton–barley rotation system had a better soil quality over rice–rape rotation system as the former had higher SQI values than the latter for both MDSs. Crop parameters did also exhibit significant relationship with the SQI values using MDS2 but it was not significant for MDS1. Our results suggest that in addition to soil chemical, physical, and biological indicators, groundwater properties particularly the WT_g and EC_g are also important for assessing soil quality in an intensively farmed coastal area.     

Wild vegetables of the Mediterranean area as valuable sources of bioactive compounds

The intake of traditionally consumed wild edible species is nowadays receiving renewed attention, due to the recognition of their potential benefits for human health. This paper represents a contribution to the knowledge of the chemical composition of different wild and under-utilized vegetables of the Mediterranean area, concerning their organic acid profile and the distribution of ascorbic and dehydroascorbic acids as vitamin C activity. Fifteen species, belonging to ten botanical families, were selected, analyzing two samples of each one from two different localities of Central Spain. Each species showed a specific organic acids fingerprint. Citric acid was 90% of total organic acids in Tamus communis; malic acid was the major one in Humulus lupulus, Taraxacum obovatum and Cichorium intybus, and oxalic acid was the main organic acid in Beta maritima, Papaver rhoeas, Silybum marianum, Foeniculum vulgare, Rumex pulcher, Silene vulgaris, Scolymus hispanicus, Rumex papillaris and Bryonia dioica. The distribution of ascorbic and dehydroascorbic acid was highly variable. Mean values for total vitamin C ranged between 1.5 and 79.4 mg/100 g. Tamus communis, R. pulcher, S. vulgaris and B. dioica, showed the highest content of AA, and together with F. vulgare and H. lupulus, the highest total vitamin C content. These results can be useful to complete food composition databases with the inclusion of wild vegetables from the Mediterranean area, contributing to enhance the diversity of the diet as well as its nutritional quality.     

Varietal and interspecific influence on micronutrient contents in citrus from the Mediterranean area

To specify the genotypic variation of Mediterranean Citrus juices, the contents of carotenoids, flavonoids, and vitamin C were determined by high-performance liquid chromatography. A selection of orange varieties and Mandarin species from the Mediterranean area (Citrus sinensis, Citrus deliciosa Ten, and Citrus clementina Hort. ex Tan) was evaluated using carotenoid profiles and flavanones contents. Among the eight varieties of orange (Salustiana, Hamlin, Shamouti, Pera, Valencia, Maltaise, Sanguinelli, and Cara-cara) and two Mandarin species, only three cultivars (Pera, Sanguinelli, and Shamouti) and the two Mandarin species displayed a high content of vitamin A (374, 381, and 272 ER L(-1) for the three orange cultivars and 1156 and 960 retinol equivalent (RE) L(-1) for the Mandarins) due to a high content of beta-cryptoxanthin. These same Citrus were also rich in hesperidin (502, 537, 552, 767, and 754 mg L(-1), respectively). Principal component analysis allowed the Mediterranean orange varieties and Mandarin species to be differentiated on the basis of nutritional criteria. Strong correlations were observed between beta-cryptoxanthin and hesperidin (r = 0.92) and between beta-cryptoxanthin and beta-carotene (r = 0.98). In contrast, vitamin C content was not correlated with carotenoids and flavanone glycosides. The Mandarin and orange group was quite distinct. The orange varieties could be divided in two groups. In addition, a diversity tree allowed a genetic approach to differentiating Citrus cultivars on the basis of Euclidian distances. This representation showed that the hybrid Clementine was nearer to its parent Mandarin than to its parent orange, suggesting that beta-cryptoxanthin was a dominant genetic factor. With regard to vitamin A, Mandarin and its hybrid Clementine appeared to be the best Citrus species.     

Cyclic influences on the heavy metal chronology in a Central Mediterranean area (Palermo Gulf,Italy)

Purpose  

The evaluation of long-term heavy metal concentrations in the Gulf of Palermo (Italy) has been carried out in order to investigate how changes of pollution levels in the last 50 years can be reflected in marine sediments. Measurements of Cr, Cu, Hg, Pb, and Zn concentrations were performed on dated fractions of a sediment core. Time series analysis has allowed to obtain information on the chronology of the heavy metal pollution of the area and to identify seasonal components and trends.