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1.
Ni and V have been determined in snow and ice collected at a high altitude location (Col du D?me) near the summit of Mont Blanc on the French-Italian border; dated from the 1960s and 1990s. Ni and V were simultaneously determined by inductively coupled plasma sector field mass spectrometry. Measured concentrations range from 6 to 700 pg g(-1) and 4 to 1,100 pg g(-1) for Ni and V, respectively. The results show pronounced seasonal variations in the concentrations of both metals, with high concentration values in summer layers and much lower values for winter layers. These seasonal variations are linked especially with the existence of inversion layers during winter months. Ni and V concentrations in excess of the contributions from rock and soil dust (Ni(excess), V(excess)) appear to be mainly associated with anthropogenic inputs, with pronounced seasonal variations. Large variations in the V(excess)/Ni(excess) ratio are observed, with a higher ratio in summer than in winter. This shows differences in anthropogenic inputs at Col du D?me during the different parts of the year. The above ratio was compared with the corresponding ratios for oil combustion from stationary sources and the exhaust from gasoline and diesel engines. It appears that Ni and V concentrations at Col du D?me are probably the result of changing combinations of contributions from oil combustion for power generation, industrial and residential uses, on one side, and automobile and truck traffic, on the other side, with possibly a significant contribution from Ni smelters in Russia during winter months.  相似文献   
2.
The mineral contents of Pistacia vera kernels were determined by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The minimum and maximum values of K, P, Ca, Mg, and S elements ranged from 6,333 to 8,064 mg/kg, 3,630 to 5,228 mg/kg, 1,614 to 3,226 mg/kg, 1,716 to 2,402 mg/kg, and 1,417 to 1,825 mg/kg, respectively. In addition, the mean values of Fe, Zn, Cu, Mn, B, Mo, Cr and Ni elements were determined as 42.48, 20.52, 12.81, 7.48, 11.31, 0.106, 0.511 and 1.67 mg/kg, respectively. Ash levels of kernels were found between 2.28 % (Urfa) and 2.79 % (Halebi). In addition, crude oil and protein contents were determined between 48.8 % (Halebi) to 55.3 % (Siirt) and 23.33 % (Uzun) to 27.16 % (Halebi), respectively.  相似文献   
3.
Agriculture, especially the irrigated sector, is the mainstay of Sudan’s economy as it accounts for 40 % of gross domestic product (GDP) and employs 70 % of the workforce. The economic viability of irrigated schemes is dependent on three factors: crop yield, water management and cropped area. The research question of this study was whether or not the current status of these factors can be sustained in order to maintain the economic viability of irrigation systems? To answer this question, a new (to the best of the author’s knowledge) approach was developed based on time series analysis, and on the Theil–Sen estimator of slope. The study defined sustainability conceptually as “the ability of an irrigation system to sustain crop yields using the optimum cropped area and water consumption to realize the economic viability of the irrigation system without a decline in soil quality and environment”. Time series datasets of crop yields, cropped area and irrigation water consumption are collected routinely by statistical departments. Any abrupt years in the development of trends were detected and related to their driving forces/causes, of which climatic conditions and marketing policies were found to be the most important. The simple approach developed proved its suitability for quantifying the progress of irrigated schemes’ towards sustainability development as tested under the conditions of Gezira irrigated scheme in Sudan—the largest singly managed irrigation scheme in the world. The scheme was found to be sustainable under the condition that the crop yield is considered as the top priority; otherwise, the sustainability of the scheme is jeopardized.  相似文献   
4.
Population viability analysis (PVA) is a reliable tool for ranking management options for a range of species despite parameter uncertainty. No one has yet investigated whether this holds true for model uncertainty for species with complex life histories and for responses to multiple threats. We tested whether a range of model structures yielded similar rankings of management and threat scenarios for 2 plant species with complex postfire responses. We examined 2 contrasting species from different plant functional types: an obligate seeding shrub and a facultative resprouting shrub. We exposed each to altered fire regimes and an additional, species‐specific threat. Long‐term demographic data sets were used to construct an individual‐based model (IBM), a complex stage‐based model, and a simple matrix model that subsumes all life stages into 2 or 3 stages. Agreement across models was good under some scenarios and poor under others. Results from the simple and complex matrix models were more similar to each other than to the IBM. Results were robust across models when dominant threats are considered but were less so for smaller effects. Robustness also broke down as the scenarios deviated from baseline conditions, likely the result of a number of factors related to the complexity of the species’ life history and how it was represented in a model. Although PVA can be an invaluable tool for integrating data and understanding species’ responses to threats and management strategies, this is best achieved in the context of decision support for adaptive management alongside multiple lines of evidence and expert critique of model construction and output.  相似文献   
5.
Caffeic acid, rosmarinic acid, rutin, apigenin 7-O-glucoside, apigenin, and acesetin were the main phenolic compounds of Origanum onites extracts in all applications. While acesetin contents ranged from 133.59 mg/100 g (U1) to 437.25 mg/100 g (S3), rosmarinic acid changed between 215.94 mg/100 g (U4) and 1120.56 mg/100 g (S2) in Origanum vulgare L. subsp. hirtum (Link) Ietsw. Both rosmarinic acid and acesetin were not found in U5 application. Only caffeic acid (19.39 mg/100 g) was found in U5 application. Rosmarinic acid contents of O. onites extract changed between 158.62 mg/100 g (U5) and 799.87 mg/100 g (S2). Generally, dominant phenolic compound of Origanum extracts was rosmarinic acid compared with other extracts. In addition, methanol:water:acetic acid mixture (S2) (95:4.5:0.5) was found as the best application. Phenolic contents of extracts obtained with U series mixtures were found low.  相似文献   
6.
Environmental Science and Pollution Research - This paper investigates the relationship between income inequality and environmental degradation for the case of Turkey between 1987 and 2017 through...  相似文献   
7.
Environmental Science and Pollution Research - This work presents a bibliographic review of the literature regarding the simultaneous removal of contaminants of emerging concern (CECs) and...  相似文献   
8.
Quantitative assessments have long been used to evaluate the condition of the natural environment, providing information for standard setting, adaptive management, and monitoring. Similar approaches have been developed to measure environmental governance, however, the end result (e.g., numeric indicators) belies the subjective and normative judgments that are involved in evaluating governance. We demonstrate a framework that makes this information transparent, through an application of the Freshwater Health Index in three different river basins in Latin America. Water Governance is measured on a 0–100 scale, using data derived from perception-based surveys administered to stakeholders. Results suggest that water governance is a primary area of concern in all three places, with low overall scores (Guandu-26, Alto Mayo-38, Bogotá-43). We conclude that this approach to measuring governance at the river basin scale provides valuable information to support monitoring and decision making, and we offer suggestions on how it can be improved.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01407-8) contains supplementary material, which is available to authorized users.  相似文献   
9.
Environmental Science and Pollution Research - Biotic invasions can predominantly alter the dynamics, composition, functions, and structure of natural ecosystems. Social insects, particularly ants,...  相似文献   
10.
In the United States, few constituents know and understand climate policy, prioritize it as a political topic, or let their voting decisions depend on it. In these conditions, representatives would not be expected to pay heed to constituents’ climate concern in their voting decisions. Still, even after controlling for the presence of interest groups, campaign finance, and legislators’ party affiliation and ideology, there is a consistent link between public opinion and votes on cap-and-trade legislation in the House (and to a lesser degree in the Senate). The same is true when public opinion is simulated based on pre-vote district characteristics. Explanations for these findings are discussed.  相似文献   
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