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881.
Phosphorus (P) is an essential macronutrient in agriculture; however, lack of reporting makes its supply chain a black box. By using literature synthesis on the P challenge, we identify four areas where the reporting process is problematic: P reserves and resources; P losses along the supply chain; P externalities; and access to data. We find that in these areas, the reporting system is inconsistent, inaccurate, incomplete, fragmented and non-transparent. We use systems analysis to discuss implications of reporting on the sustainability of the P supply chain. We find that reporting is essential for the achievement of global P governance and the human right to adequate food. It can also inform decision makers and other impacted stakeholders on policies on agriculture, food security, pollution and international conflict. An improved P reporting process also allows a better evaluation of global sustainability commitments such as the United Nations Sustainable Development Goals.  相似文献   
882.
Environmental Science and Pollution Research - Highly time-resolved particle number size distributions (PNSDs) were evaluated during 5 years (2013–2017) at four background stations in the...  相似文献   
883.
Environmental Science and Pollution Research - The present study evaluates the development of visible injury related to phytotoxic ozone dose (PODy) in native tropical species Astronium graveolens...  相似文献   
884.
Environmental Science and Pollution Research - Organochlorine pesticides have generated public concern worldwide because of their toxicity to human health and the environment, even at low...  相似文献   
885.

The contamination of soils and water with copper (Cu) can compromise the crops production and quality. Fungicides containing Cu are widely and intensively used in viticulture contributing to environmental contamination and genotoxicity in Vitis vinifera L. Despite the difficulty in reproducing field conditions in the laboratory, hydroponic solutions enriched with Cu (1, 10, 25 and 50 μM) were used in forced V. vinifera cuttings to evaluate the DNA damage in leaves of four wine-producing varieties (‘Tinta Barroca’, ‘Tinto Cão’, ‘Malvasia Fina’ and ‘Viosinho’). Alkaline comet assay followed by fluorescence in situ hybridisation (Comet-FISH) was performed with the 45S ribosomal DNA (rDNA) and telomeric [(TTTAGGG)n] sequences as probes. This study aimed to evaluate the tolerance of the four varieties to different concentrations of Cu and to determine which genomic regions were more prone to DNA damage. The comet assay revealed comets of categories 0 to 4 in all varieties. The DNA damage increased significantly (p < 0.001) with the Cu concentration. ‘Tinto Cão’ appeared to be the most sensitive variety because it had the highest DNA damage increase in 50 μM Cu relative to the control. Comet-FISH was only performed on slides of the control and 50 μM Cu treatments. Comets of all varieties treated with 50 μM Cu showed rDNA hybridisation on the head, ‘halo’ and tail (category III), and their frequency was significantly higher than that of control. The frequency of category III comets hybridised with the telomeric probe was only significantly different from the control in ‘Malvasia Fina’ and ‘Tinta Barroca’. Comet-FISH revealed partial damage on rDNA and telomeric DNA in response to Cu but also in control, confirming the high sensitivity of these genomic regions to DNA fragmentation.

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886.
Environmental Science and Pollution Research - The study used scattered literature to summarize the effects of excess Cd, As, and Pb from contaminated soils on plant secondary metabolites/bioactive...  相似文献   
887.
Some conservation prioritization methods are based on the assumption that conservation needs overwhelm current resources and not all species can be conserved; therefore, a conservation triage scheme (i.e., when the system is overwhelmed, species should be divided into three groups based on likelihood of survival, and efforts should be focused on those species in the group with the best survival prospects and reduced or denied to those in the group with no survival prospects and to those in the group not needing special efforts for their conservation) is necessary to guide resource allocation. We argue that this decision-making strategy is not appropriate because resources are not as limited as often assumed, and it is not evident that there are species that cannot be conserved. Small population size alone, for example, does not doom a species to extinction; plants, reptiles, birds, and mammals offer examples. Although resources dedicated to conserving all threatened species are insufficient at present, the world's economic resources are vast, and greater resources could be dedicated toward species conservation. The political framework for species conservation has improved, with initiatives such as the UN Sustainable Development Goals and other international agreements, funding mechanisms such as The Global Environment Facility, and the rise of many nongovernmental organizations with nimble, rapid-response small grants programs. For a prioritization system to allow no extinctions, zero extinctions must be an explicit goal of the system. Extinction is not inevitable, and should not be acceptable. A goal of no human-induced extinctions is imperative given the irreversibility of species loss.  相似文献   
888.
The reproductive patterns of four Antarctic gorgonian species have been investigated. Two of them, Dasystenella acanthina and Thouarella sp., present the bottle-brush-shape type; the other two, Fannyella rossii and Fannyella spinosa, are fan-shaped. Two different reproductive patterns have been observed in D. acanthina and Thouarella sp., which point to two size classes in the frequency distribution of oocytes. This feature indicates a reproduction cycle with overlapping generations, being each of them of more than one year, probably with seasonal spawning. F. rossii and F. spinosa show only one size class of oocytes, which could point towards an annual reproductive cycle. The presence of larvae in the gastrovascular cavities in both Fanyella species and Thoaurella sp. is a sign of a possible larvae release during austral summer. The number of oocytes per polyp ranges from 1.1 ± 0.10 SE to 1.5 ± 0.06 SE, and the size ranges from 50 to 1200 μm. The number of spermatic cysts ranges from 2.6 ± 0.19 SE to 5.0 ± 0.21SE, and their sizes range from 50 to 800 μm. These values are comparable to the reproductive trends and features found in gorgonians from other latitudes, which correspond in some cases with similar morphotypes. These coincident strategies could be related to morphological similarities rather than with latitude or water temperature. The results of this study indicate that octocoral morphology may play a crucial role in determining the reproductive output of these organisms.  相似文献   
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