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The influence of salinization on seed germination and plant growth under mono and polyculture
2020
Sea level rise induced-salinization is lowering coastal soils productivity. In order to assess the effects that increased salinity may provoke in terrestrial plants, using as model species: Trifolium pratense, Lolium perenne, Festuca arundinacea and Vicia sativa, two specific objectives were targeted: i) to determine the sensitivity of the selected plant species to increased salinity (induced by seawater-SW or by NaCl, proposed as a surrogate of SW) and, ii) to assess the influence of salinization in total biomass under different agricultural practices (mono- or polycultures).The four plant species exhibited a higher sensitivity to NaCl than to SW. Festuca arundinacea was the most tolerant species to NaCl (EC₅₀,ₛₑₑd gₑᵣₘᵢₙₐₜᵢₒₙ and EC₅₀,gᵣₒwₜₕ of 18.6 and 10.5 mScm⁻¹, respectively). The other three species presented effective conductivities in the same order of magnitude and, in general, with 95% confidence limits overlapping. Soil moistened with SW caused no significant adverse effects on seed germination and growth of L. perenne. Similar to NaCl, the other three species, in general, presented a similar sensitivity to SW exposure with EC₅₀,ₛₑₑd gₑᵣₘᵢₙₐₜᵢₒₙ and EC₅₀,gᵣₒwₜₕ within the same order of magnitude and with confidence limits overlapping.The agricultural practice (mono-vs polyculture) showed some influence on the biomass of each plant species. When considering total productivity, for aerial and root biomass, it was higher in control comparatively to salinization conditions. Under salinization stress, the practice of polyculture was associated with a higher aerial and root total biomass than monocultures (for instance with combinations with T. pratense and F. arundinacea).Results suggest that the effects of salinity stress on total productivity may be minimized under agricultural practices of polyculture. Thus, this type of cultures should be encouraged in low-lying coastal ecosystems that are predicted to suffer from salinization caused by seawater intrusions.
Mostrar más [+] Menos [-]Chemical characterization of polycyclic aromatic hydrocarbons (PAHs) in 2013 Rayong oil spill-affected coastal areas of Thailand
2018
Pongpiachan, S. | Hattayanone, M. | Tipmanee, D. | Suttinun, O. | Khumsup, C. | Kittikoon, I. | Hirunyatrakul, P.
Among Southeast Asian countries, Thailand has gradually accustomed to extremely prompt urbanization, motorization, and industrialization. Chonburi and Rayong provinces are two provinces involved in “eastern seaboard” industrial zones, which is an emerging economic region that plays a key role in Thailand's economy. The 2013 Rayong oil spill did not only cause damages to the coastal and maritime environment, but also undermine trust in the overall safety system and negatively affect the investor confidence. In this study, 69 coastal soils collected around Koh Samed Island were chemically extracted and analyzed for 15 PAHs by using a Shimadzu GCMS-QP2010 Ultra system comprising a high-speed performance system with ASSP function. In this study, numerous diagnostic binary ratios were applied to identify potential sources of PAHs. Advanced statistical techniques such as hierarchical cluster analysis coupled with principal component analysis were also conducted for further investigations of source identifications.
Mostrar más [+] Menos [-]Distribution and source analysis of heavy metals in soils and sediments of Yueqing Bay basin, East China Sea
2017
Yang, Xiaohui | Wu, Pengbao | Yin, Aijing | Zhang, Huan | Zhang, Ming | Gao, Chao
Concentrations of heavy metals in coastal soils, stream sediments and intertidal sediments of Yueqing Bay basin were analyzed to study their distribution and trace the possible sources. According to various single- and multi-index methods, heavy metal enrichment, especially for Cu, Zn, Cr and Ni in stream sediments, should draw environmental concern. Controlling factors such as inorganic scavengers, organic matter, sample grain size and hydrodynamic conditions were identified to influence the transportation and distribution of metals within coastal soils and sediments. Principal component analysis indicated that most metals in soils and stream sediments originate primarily from natural and anthropogenic sources, respectively. Most metals in intertidal sediments, originating both from natural processes and human activities, tend to be concentrated in fine particles. The exchange of water and sediment between the bay and open waters is strong enough to keep the metals in the tidal flats from rising to very high levels.
Mostrar más [+] Menos [-]Heavy metal pollution and assessment in the tidal flat sediments of Haizhou Bay, China
2013
Zhang, Rui | Zhou, Li | Zhang, Fan | Ding, Yingjun | Gao, Jinrong | Chen, Jing | Yan, Hongqiang | Shao, Wei
The heavy metal inventory and the ecological risk of the tidal flat sediments in Haizhou Bay were investigated. Results show that the average concentrations of heavy metals in the surface sediments exceeded the environment background values of Jiangsu Province coastal soil, suggesting that the surface sediments were mainly polluted by heavy metals (Cd, Cr, Cu, Mn, Pb and Zn). In addition, the profiles of heavy metals fluxes can reflect the socio-economic development of Lianyungang City, and heavy metals inputs were attributed to anthropogenic activities. Cr, Cu, Pb and Zn were mainly present in the non-bioavailable residual form in surface sediments, whereas Cd and Mn were predominantly in the highly mobile acid soluble and reducible fractions. The ecological risk of the polluted sediments stemmed mainly from Cd and Pb. According to the Sediment quality guidelines (SQGs), however, the adverse biological effects caused by the heavy metals occasionally occurred in tidal flat.
Mostrar más [+] Menos [-]Soil Depletion of Ca, Mg and K Due to Vicinal Intensive Hog Farming Operation Located in East Mediterranean
2012
Michalopoulos, Charalampos | Liodakis, Stylianos
One of the main environmental impacts of concentrated animal feeding operations is soil degradation in the vicinity of the livestock breeding facilities due to substances such as ammonia emitted from the various stages of the process. In this research, the soil degradation effects of an intensive hog farming operation (IHFO) located at a Mediterranean limestone soil coastal area have been investigated. Soil samples of the upper mineral soil were taken in various distances and directions from the IHFO boundaries. Thirteen experimental cycles were carried out in the duration of 1.5 years starting in March 2009 until October 2010. The soil samples were analysed on total, exchangeable and water-soluble Ca, Mg and K as well as water-soluble ammonium concentrations. Significantly lower concentrations of the exchangeable and water-soluble base cations were observed on soil samples at increasing proximity downwind from the farm (south). Southern soil average concentrations of exchangeable base cations ranged between 78.6 and 128.52 mmol Ca²⁺ kg⁻¹ soil, 8.42–21.39 mmol Mg²⁺ kg⁻¹ soil and 4.25–8.1 mmol K⁺ kg⁻¹ soil, respectively. Southern soil average concentrations of water-soluble base cations ranged between 0.57 and 2.17 mmol Ca²⁺ kg⁻¹ soil, 0.16–0.89 mmol Mg²⁺ kg⁻¹ soil and 0.48–0.95 mmol K⁺ kg⁻¹ soil, respectively.
Mostrar más [+] Menos [-]Soil Mobilisation of Al, Fe and Mn Due to Vicinal Intensive Hog Farming Operation Located in East Mediterranean
2012
Michalopoulos, Charalampos | Liodakis, Stylianos
Concentrated Animal Feeding Operation activities lead to soil degradation in vicinity with the livestock breeding facilities, mainly due to ammonia emissions from the various stages of the process. In this research, the soil degradation effects of an intensive hog farming operation (IHFO) located at a Mediterranean limestone soil coastal area, have been investigated. Soil samples of the upper mineral soil were taken in various distances (10–1,500 m) and directions from the IHFO boundaries. Thirteen experimental cycles were carried out in the duration of 1.5 years starting in March 2009 until October 2010. The soil samples were analysed on total, exchangeable and water-soluble Al, Fe and Mn. Significantly higher concentrations of the exchangeable and water-soluble Al, Fe and Mn were observed on soil samples at increasing proximity downwind from the farm (south). Southern soil average concentrations of exchangeable Al³⁺, Fe³⁺ and Mn²⁺ ranged between 3.56 and 7.45 mmol Al³⁺ kg⁻¹ soil, 5.85 and 7.11 mmol Fe³⁺ kg⁻¹ soil and 2.36 and 5.03 mmol Mn²⁺ kg⁻¹ soil, respectively. Southern soil average concentrations of water-soluble Al, Fe and Mn forms ranged between 1.1 and 4.6 ppm Al, 0.5 and 0.8 ppm Fe and 0.4 and 1 ppm Mn, respectively.
Mostrar más [+] Menos [-]The Simulated Effects of Iron Dust and Acidity During the Early Stages of Establishment of Two Coastal Plant Species
2009
Kuki, K. N. | Oliva, M. A. | Costa, António Carlos (António Carlos Borges Santos da)
In Brazil's littoral, many iron ore industries are located in areas of restinga, a type of coastal ecosystem; such industries represent stationary sources of iron and acid particulates. The industrial sector is under expansion, threatening the already fragile ecosystem. In the present study, the simulated impact of these emissions was studied on the early establishment stages of two native plant species, Sophora tomentosa and Schinus terebinthifolius. The results indicate that S. tomentosa display deficient germination and low root tolerance when exposed to iron dust and acidity. Toxic iron concentrations were found to accumulate only in the roots of S. tomentosa plants exposed to increasing doses of iron dust. In these plants, initial growth was reduced, leading to the conclusion that S. tomentosa was unable to regulate, and, thus, to overcome, the effects of the iron dust in the substrate. In contrast, the germination, root tolerance index, and initial growth of S. terebinthifolius were not affected by iron dust and acidity, revealing the species' resistance to these pollutants. We propose that under similar field conditions, S. tomentosa would be adversely affected, whereas S. terebinthifolius would thrive. On a long-term basis, this imbalance is likely to interfere in the vegetational composition and dynamics of the affected ecosystem.
Mostrar más [+] Menos [-]The Impact of Penguins on the Content of Trace Elements and Nutrients in Coastal Soils of North Western Chile and the Antarctic Peninsula Area
2017
Espejo, Winfred | Celis, José E. | Sandoval, Marco | González Acuña, Daniel | Barra, Ricardo | Capulín, Juan
In isolated areas without direct human impact where several species of seabirds nest, transformations affecting the soil come mainly from natural processes, such as chemical enrichment caused by seabirds. Penguins constitute an important bird biomass in the Southern Hemisphere, where they breed in colonies on different sites from 100 to thousands of individuals. The accumulation of trace elements and nutrients in soils within two perennial colonies of Humboldt penguins (Spheniscus humboldti) located in north western Chile and three colonies of Adélie penguins (Pygoscelis adeliae) in the Antarctic Peninsula area were investigated here. Surface soil samples were collected directly from nesting sites. Control samples were taken outside the colonies within sites adjacent to the nesting areas, but not affected by bird excrement. The contents of Cd, Co, Cr, Cu, Mo, Ni, Sr, V and Zn were determined by inductively coupled plasma optical emission spectrometry. Ammonium (NH₄) and nitrate (NO₃) ions were determined colorimetrically. Extractable potassium (K) was determined by flame emission spectrometry, and available phosphorus (Olsen-P) was determined by spectrophotometry. The highest concentrations of trace metals (Cd, Co, Cr, Cu, Mo, V and Zn) and macronutrients (available N, K and P), along with an increase in salinity and acidity levels, were found directly below the seabird colony, a situation occurring in northern Chile as well as in the Antarctic Peninsula area, highlighting the role that penguins have as bio-vectors on generating geochemical changes in different ecosystems. Some terrestrial plants and animals that live near those penguin colonies might be affected at a greater level than the organisms that live in sites similar but distant from colonies of birds. New data about the role of these species of seabirds as bio-vectors of chemical contaminants are added.
Mostrar más [+] Menos [-]Trace Element Concentrations in Biotic Matrices of Gentoo Penguins (Pygoscelis Papua) and Coastal Soils from Different Locations of the Antarctic Peninsula
2015
The aim of this work is to increase the information on trace metals in seabirds and coastal soils in the Antarctica. Concentrations (mg kg⁻¹dry weight) of Cd, Cu, Cr, Ni, Mn, Zn and Pb were determined by ICP-MS in fresh excreta and feathers of Gentoo penguins as well as in soils around the nesting sites where this species inhabits. Samples were collected in four locations throughout the Antarctic Peninsula (January 2014): O’Higgins Base, Stranger Point, Neko Harbor and Doumer Island. The highest levels of elements were found in excreta from O’Higgins Base (2.92, 266.83, 2.99, 44.75, 18.15, 1.68 and 317.92 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively) and Stranger Point (1.97, 222.51, 2.98, 36.62, 13.41, 1.46 and 201.18 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively. Similarly, the highest levels were found in feathers from O’Higgins Base (0.21, 20.89, 1.44, 1.19, 5.90, 0.63 and 64.07 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively) and Stranger Point (0.14, 19.65, 1.47, 1.23, 3.85, 0.60 and 64.19 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively). In soils, the highest levels were found in O’Higgins Base (4.31, 421.94, 64.75, 404.76, 28.13, 281.54 and 484.99 for Cd, Cu, Cr, Mn, Ni, Pb and Zn, respectively), whereas the lowest levels were found in Neko Harbor and Doumer Island. These results observed could be related to the major human presence in the northern area of the Antarctic Peninsula and large-scale transport of pollutants. The metals detected in the excreta of the Gentoo penguin can contribute to increase the contamination of coastal terrestrial ecosystems, which could also affect other living organisms.
Mostrar más [+] Menos [-]Effects of nesting yellow-legged gulls (Larus cachinnans pallas) on the heavy metal content of soils in the Cies Islands (Galicia, North-West Spain)
1998
Perez, X.L.O. (Departamento de Edafoloxia e Quimica Agricola, Facliltade de Bioloxia, 15 706 Santiago de Compostela (Spain))