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51.
Environmental Science and Pollution Research - Arsenic (As) indelibly exists in the environment and may reach to a food chain. Flavors and herbs are recognized sources of natural antioxidants that...  相似文献   
52.
Environmental Science and Pollution Research - The aim of this study is to describe the existence of the inflammatory marker nuclear factor kappa light chain B lymphocyte protein (NF-?B P65)...  相似文献   
53.
Environmental Science and Pollution Research - The contamination left by abandoned mines demands sustainable mitigation measures. Hence, the aim of this study was to examine the phytoremediator...  相似文献   
54.
Water represents 71% of all earth area and about 97% of this water is salty water. So, only 3% of the overall world water quantity is freshwater. Human can benefit only from 1% of this water and the remaining 2% freeze at both poles of earth. Therefore, it is important to preserve the freshwater through increasing the plants consuming salty water. The future prosperity of feed resources in arid and semi-arid countries depends on economic use of alternative resources that have been marginalized for long periods of time, such as halophytic plants, which are one such potential future resource. Halophyte plants can grow in high salinity water and soil and to some extent during drought. The growth of these plants depends on the contact of the salted water with plant roots as in semi-desert saline water, mangrove swamps, marshes, and seashores. Halophyte plants need high levels of sodium chloride in the soil water for growth, and the soil water must also contain high levels of salts, as sodium hydroxide or magnesium sulfate. There are many uses for halophyte plants, including feed for animals, vegetables, drugs, sand dune stabilizers, wind shelter, soil cover, wetland cultivation, laundry detergents, and paper production. This paper will focus on the use of halophytes as a feed additive for animals. In spite of the good nutritional value of halophytes, some anti-nutritional factors as nitrates, nitrite complexes, tannins, glycosides, phenolic compounds, saponins, oxalates, and alkaloids may be present in some of them. The presence of such anti-nutritional agents makes halophytes unpalatable to animals, which tends to reduce feed intake and nutrient use. Therefore, the negative effects of these plants on animal performance are the only objection against using halophytes in animal feed diets. This review article highlights the beneficial impact of considering halophytes in animal feeding on saving freshwater and illustrates its nutritive value for livestock from different aspects.  相似文献   
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56.
The survey of fish fauna in Kaveri River at polluted and unpolluted sites revealed a direct effect on the distribution of fishes in that 14 species were observed in unpolluted site and only 6 species in polluted site. Further, the haemotological parameters like RBC, WBC and haemoglobin content increased in fishes collected from polluted site whereas the organic constituents of muscle decreased in the above fishes when compared to the fishes of unpolluted site. The reason for the above changes is discussed.  相似文献   
57.
ABSTRACT

The seasonal variations in Pseudo-nitzschia species and domoic acid (DA) concentration were investigated, at three shellfish farms in SW coastal Mediterranean. In parallel, the toxicity of mussels was tested. Two distinct groups of species were enumerated according to morphology and size (Pseudo-nizschia delicatissima and P. seriata groups). DA was detected over a nine-week period from July to October 2012 in the Lagoon, with a maximum concentration recorded in July (12.71?ng?DA?L?1). DA was positively correlated with the presence of P. seriata-group and P. delicatissima-group and was mostly occurred during P limitation period in seawater. No DA was found in mussels that were collected during the period of DA absence in seawater. Our results suggest that temperature, salinity, inorganic and organic nutrients were significant for the seasonal dynamics of P. seriata and P. delicatissima groups, but that the P limitation was the most driving factor for DA production in these areas. The relative influence of environmental factors should be further studied to better understand the recent surfacing of massive blooms of toxigenic Pseudo-nitzschia in SW Mediterranean coast.  相似文献   
58.
Managing mangroves in Bangladesh: A strategy analysis   总被引:1,自引:0,他引:1  
Bangladesh, favoured by a tropical climate, houses the world’s largest stretch of mangroves forests (Sundarbans Reserved Forest) and plantations. Around half of the forests of the country occur in the coastal zone. People extract various goods and services from the mangroves. Nevertheless the mangrove forests are depleting. Although the extent of the Sundarbans forest has not changed much, its decline is of a qualitative nature. Mangrove plantations are increasing in area but they are losing growing stock. To arrest this, Bangladesh has adopted several strategies. The ‘Sustainable Ecosystem Management’ strategy has now been adopted instead of the ‘Sustained Yield Principle’. Biodiversity conservation and enhancement has been taken as a key management goal. A zoning system is being developed for both production and protection purposes. The government facilitates alternative income for the local people by generating activities for the communities which are dependent on the forest. Different non-governmental organizations collaborate with the government in reducing the local people’s dependence on the forest. Coastal plantations are erected to protect people from cyclones and to make the land more suitable for habitation. Through this greening of the coastal belt tree plantation is encouraged in coastal villages. Coastal embankments are being planted and leased to poor settlers in exchange for routine maintenance of the embankments. Plantations on newly accreted mud flats help in stabilizing the land, which can later on be settled by victims of erosion elsewhere. These adopted management measures do not only contribute to forestry resource management but also to the social, environmental and economic wellbeing of the coastal communities. These efforts are at present being integrated into an Integrated Coastal Zone Management (ICZM) project.  相似文献   
59.
Elie Gaget  Diego Pavón-Jordán  Alison Johnston  Aleksi Lehikoinen  Wesley M. Hochachka  Brett K. Sandercock  Alaaeldin Soultan  Hichem Azafzaf  Nadjiba Bendjedda  Taulant Bino  Luka Božič  Preben Clausen  Mohamed Dakki  Koen Devos  Cristi Domsa  Vitor Encarnação  Kiraz Erciyas-Yavuz  Sándor Faragó  Teresa Frost  Clemence Gaudard  Lívia Gosztonyi  Fredrik Haas  Menno Hornman  Tom Langendoen  Christina Ieronymidou  Vasiliy A. Kostyushin  Lesley J. Lewis  Svein-Håkon Lorentsen  Leho Luigujõe  Włodzimierz Meissner  Tibor Mikuska  Blas Molina  Zuzana Musilová  Viktor Natykanets  Jean-Yves Paquet  Nicky Petkov  Danae Portolou  Jozef Ridzoň  Samir Sayoud  Marko Šćiban  Laimonas Sniauksta  Antra Stīpniece  Nicolas Strebel  Norbert Teufelbauer  Goran Topić  Danka Uzunova  Andrej Vizi  Johannes Wahl  Marco Zenatello  Jon E. Brommer 《Conservation biology》2021,35(3):834-845
Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species. An evaluation of the relative importance of colonization-extirpation processes is important to inform conservation strategies that aim for both climate debt reduction and species conservation. We assessed the colonization-extirpation dynamics involved in community changes in response to climate inside and outside PAs. To do so, we used 25 years of occurrence data of nonbreeding waterbirds in the western Palearctic (97 species, 7071 sites, 39 countries, 1993–2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate species turnover induced by temperature increase. We determined whether thermal community adjustment was associated with colonization by warm-dwelling species or extirpation of cold-dwelling species by modeling change in standard deviation of the CTI (CTISD). Using linear mixed-effects models, we investigated whether communities in PAs had lower climatic debt and different patterns of community change than communities outside PAs. For CTI and CTISD combined, communities inside PAs had more species, higher colonization, lower extirpation, and lower climatic debt (16%) than communities outside PAs. Thus, our results suggest that PAs facilitate 2 independent processes that shape community dynamics and maintain biodiversity. The community adjustment was, however, not sufficiently fast to keep pace with the large temperature increases in the central and northeastern western Palearctic. Our results underline the potential of combining CTI and CTISD metrics to improve understanding of the colonization-extirpation patterns driven by climate warming.  相似文献   
60.
Deepwater rice is grown in South and Southeast Asia on 11 million hectares flooded deeply during the monsoon. Surveys for the incidence of stem borers in deepwater rice in Bangladesh from 1977 to 1980, and in Thailand during 1981 and 1982, showed that borer incidence and species composition were remarkably similar. Scirpophaga incertulas (Walker) usually comprised more than 90% of the borer population and was almost exclusively present during the main flooding period. Chilo polychrysus (Meyr.) comprised 11% and Sesamia inferens (Walker) 6% of the population in the pre-flood and ripening stages.Low borer activity in the early part of the season was explained by a low nucleus population, the synchronous planting of deepwater rice, and severe moisture stress and high temperatures in the pre-flood period. In Bangladesh, a severe drought in 1979 limited Scirpophaga incertulas populations to unusually low levels until the flowering stage. In Thailand, drier conditions, the lack of an intervening rice crop in the dry season and a longer pre-flood period, appeared to severely restrict early season borer activity. The onset of flooding and stem elongation provided a more favourable environment for S. incertulas. Borer activity increased steadily during the first 3–4 months of flooding, to average 23% damaged stems (26 m?2) and 13 borer immature stages/100 stems (13 m?2) by the flowering stage. Borer activity continued at about the same level as the water receded, to reach maximum annual levels of 38–44% damaged stems (35 m?2) at the late-ripening stage. At harvest, 60% of the fields were at outbreak level (>40% damaged stems). Such high levels of damage are explained by the long growth period of deepwater rice, favourable weather during the flooding period, and the optimum habitat of the elongated stem. S. incertulas populations then crashed to low levels; the larvae entering diapause in the field stubble. Although related to actual damage, the deadheart and whitehead symptoms grossly under-estimated the extent of stem damage.  相似文献   
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