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41.
42.
Assunta Florenzano Anna Maria Mercuri Aurora Pederzoli Paola Torri Giovanna Bosi Linda Olmi Rossella Rinaldi Marta Bandini Mazzanti 《Geoarchaeology》2012,27(1):34-47
This paper presents the study of parasite remains recovered in pollen samples collected from archaeological layers. Laboratory treatment enabled us to obtain very high concentrations of both pollen and parasite eggs from the same samples. The case study of the site of Piazza Garibaldi in Parma, a town in the Po plain, is reported. The site was a sacred area in Roman times and a market square in Medieval times (10th–11th century A.D.). Pollen, seeds, and fruits from the latter phase were collected from four Medieval pits and one cesspit. After a palynological treatment including sieving, floating, and light acetolysis, abundant quantities of parasite eggs were extracted. Human and animal parasite eggs belonging to Trichuris, Ascaris, Taenia/Echinococcus, Capillaria, Dicrocoelium, and Diphyllobothrium were found. The analyses of animal and plant remains identified in the same samples suggested that the pit infillings consisted of waste, human and animal excrements, deteriorated plant food, and refuse of grapes. Therefore, parasite remains help the interpretation of archaeobotanical data in identifying human behaviors and site functions. 相似文献
43.
Filippo Santucci de Magistris Anna d’Onofrio Augusto Penna Rodolfo Puglia Francesco Silvestri 《Natural Hazards》2014,74(3):2005-2035
The prediction of the variability of the seismic ground motion in a given built-up area is considered an effective tool to plan appropriate urban development, to undertake actions on seismic risk mitigation and to understand the damage pattern caused by a strong-motion event. The procedures for studying the seismic response and the seismic microzonation of an urban area are well established; nevertheless, some controversial points still exists and are discussed here. In this paper, the selection of a reference input motion, the construction of a subsoil model and the seismic response analysis procedures are discussed in detail, based on the authors’ experience in two Italian case histories: the seismic microzonation of the city of Benevento, which was a predictive study, and the simulation of seismic response and damage distribution in the village of San Giuliano di Puglia, which was a retrospective analysis. 相似文献
44.
45.
The post-agreement period typically is characterized by negotiations between various stakeholders to reach mutually beneficial and acceptable means to achieve national implementation of, and compliance with, treaty provisions. National ratification of international environmental agreements is often the first subprocess of these ‘postagreement negotiations’. This article places ratification negotiations within the larger conceptual context of postagreement negotiations, with the goal of understanding and explaining problems of treaty Implementation. An empirical analysis reveals that delay in national ratification of environmental agreements is a chronic problem, but is worse for complex, multi-issue treaties. Strong public concern over local environmental issues, low quality of life, low national wealth, and low public research and development expenditures for environmental protection contribute to ratification delay. Ultimately, the authors are interested in identifying ways of improving the international negotiation process that initiated these later problems in implementation. Recommendations are offered in this regard. 相似文献
46.
In the Thames Estuary at the eastern end of Long Island Sound, most mussels achieve maximal gonadal development during the summer and larval settlement occurs primarily during the fall. The timing of reproductive events is several months later than has been reported for other populations of mussels in Long Island Sound but corresponds to that of mussels inhabiting the south shore of Long Island. The data support the growing body of evidence which indicates that temperature is not a major factor determining the reproductive period of this bivalve. 相似文献
47.
The results of an extensive study of streamwater chemistry during stormflow events, for a montane Mediterranean area, are presented. Four groups of variables are identified as having contrasting behaviour: alkalinity and pH; nitrate and potassium; sulphate and chloride; sodium, calcium and magnesium. The results show a complex pattern of response to flow that can be broadly linked to: (1) antecedent hydrological conditions; (2) rainfall intensity; (3) supplies of water from chemically distinct areas within the catchment. However, comparisons between this study and a parallel one which examined the composition of waters within the catchment, show that it is presently impossible to quantify the relative supplies from each part of the catchment. The findings are reviewed in relation to analogous studies within a European setting and in relation to modelling initiatives. 相似文献
48.
A modern tsunami catalogue has been compiled for the region of Cyprus-Levantine Sea in which 24 certain or possible local
tsunamis are listed from antiquity up to the present time, while six regional tsunamis, generated in the Hellenic arc, are
documented which affected the region. Another set of 13 doubtful events not included in the catalogue are discussed. Tsunami
intensities k and K were re-evaluated using the classic 6-grade and the new 12-grade intensity scales, respectively. The strongest tsunamis reported
in the region of interest are those of 551 AD, 749, 1068, 1201, 1222, 1546 and 1759, all occurring along the Levantine coast
from Gaza northward, with the exception of the 1222 wave which occurred in the Cyprean arc. The causative earthquakes, however,
occur on land and are associated with the left-lateral strike-slip Levantine rift and, as such, remain unexplained. In this
paper we speculate on the mechanism of these events. A second tsunami zone follows the Cyprean arc, where the situation of
subaqueous seismogenic sources favours the generation of tsunamis by co-seismic fault displacements. Submarine or coastal
earth slumping, however, may be an additional tsunamigenic component. Based on historical data, the average tsunami recurrence
in the Cyprus-Levantine Sea region is roughly estimated to be around 30 years, 120 years and 375 years for moderate (k/K ≥ 2/3), strong (k/K ≥ 3/5) and very strong (k/K ≥ 5/8) events, respectively. The rate of tsunami occurrence equals 0.033, 8.3 × 10−3 and 2.7 × 10−3 events/year for intensity k/K ≥ 2/3, 3/5 and 5/8, respectively. For a Poissonian (random) process the probabilities of observing at least one moderate,
strong or very strong tsunami are 0.28, 0.01 and 3 × 10−3 within 1 year, 0.81, 0.34 and 0.13 within 50 years and 0.96, 0.56 and 0.24 within 100 years, respectively. The tsunami potential
in the Cyprus-Levantine Sea area is low relative to other Mediterranean tsunamigenic regions. However, the destructiveness
of some historical events indicates the need to evaluate tsunami hazard by all available means. In addition, remote tsunamigenic
sources, such as those of 1303 and 1481 in the eastern Hellenic arc, are able to threaten the coasts of the Cyprus-Levantine
region and, therefore, such regional tsunamis should be taken into account in the evaluation of the tsunami risk of the region. 相似文献
49.
Vladimir A.SANKOV Anna V.PARFEEVETS Andrey I.MIROSHNITCHENKO Aleksey V.SANKOV Amgalan BAYASGALAN Sodnomsambuu DEMBEREL 《地学前缘》2022,29(1):245-265
阿穆尔板块西部边界在蒙古境内的空间位置尚不清楚,并且活动断层构造及其沿线地壳的应力状态研究较少。本文在沿此边界的三个区域——杭爱—肯特构造鞍部、布尔古特地块(鄂尔浑—土拉交汇处)和色楞格地块(包括色楞格凹陷和布伦—努鲁隆起),利用空间图像解译、地形起伏度分析、地质构造资料以及构造压裂和沿裂缝位移资料重建构造古应力,对活动断层进行研究。研究表明,活动断裂继承了古生代和中生代古构造的非均质性。这些断层沿着板块边界并不是单一的带,而是成簇的。它们的运动取决于走向:亚纬向断层是具有一定逆分量的左旋走滑断层,北西向断层是逆断层或逆冲断层,通常具有右旋走滑分量,海底断层是右旋走滑断层,北东向断层是正断层。位于色楞格凹陷和杭爱东部的断裂构造的活动始于上新世。逆断层和走滑断层与上新世情况不符,但多与更新世地貌相符,表明其活动年代较晚,为更新世时期。利用构造断裂和沿断裂的位移,重建活动断裂带变形末阶段的应力应变状态,结果表明断裂在最大挤压轴的北北东和北东方向上以压缩和走滑为主。只有在色楞格凹陷内,以扩张和走滑类型的应力张量为主,且在最小挤压轴的北西走向尤为显著。在南部,杭爱东部(鄂尔浑地堑)内有1个以扩张机制为主的局部区域,说明蒙古中部断裂在更新世—全新世阶段的活动以及现代地震活动主要受与印度斯坦和欧亚大陆汇聚过程相关的东北方向的附加水平挤压的控制。使研究区地壳产生走滑变形、贝加尔湖裂谷发散活动以及阿穆尔板块东南运动的另一个因素是东南方向软流圈流动对岩石圈底部的影响。阿穆尔板块和蒙古地块之间的边界在构造结构上是零碎的,代表了覆盖整个蒙古西部变形带的边缘部分。 相似文献
50.
ABSTRACTThe Australian government’s proposal to expand the Snowy Hydro Scheme to include a second pumped hydro energy storage (PHES) system, and support for feasibility studies for PHES in Tasmania, offer an opportunity to incorporate more intermittent renewable energy generation into the National Energy Market. However, the infrastructure construction required for PHES expansion may have negative effects for biodiversity in subalpine and alpine areas. To identify the potential effects of PHES on biodiversity in Kosciuszko National Park (KNP), this systematic literature review assesses: (i) the key environmental disturbances likely to arise from PHES construction; and (ii) the specific impacts of these construction processes on biodiversity in subalpine and alpine environments. We find that the effects of PHES construction-related disturbances are likely to be negative for subalpine and alpine biodiversity, with impacts including the proliferation of exotic flora, habitat loss resulting from vegetation clearing, altered landscape hydrology and reduced water quality. Management recommendations to limit these impacts are provided and further research is recommended to assess: (i) the effects of PHES on fish populations in alpine reservoirs; (ii) the utility of spoil as artificial habitat for endemic fauna; and (iii) the chemical and physical impacts of spoil dumping in alpine reservoirs. 相似文献