Seasonal and Long-Term Variability of Coccolithophores in the Black Sea According to Remote Sensing Data and the Results of Field Investigations

Based on satellite data from the SeaWiFS, MODIS-Aqua, and MODIS-Terra scanners, the long-term dynamics of coccolithophores in the Black Sea and their large-scale heterogeneity have been studied. During the twenty years in May and June, mass development of coccolithophores population of different intensities was recorded annually. Summer blooms of coccolithophores reached peak levels in 2006, 2012, and 2017, after abnormally cold winters. It was noted that in conditions of low summer temperatures, the blooming of coccolithophores could be significantly reduced or acquire a local character (2004). In the anomalous cold summer of 2001, coccolithophore blooms were replaced by the mass growth of diatoms. Over twenty years, numerous signs of coccolithophores mass development in the cold season have been revealed. Winter blooms develop mainly in warm winters with periods of low wind activity. The formation of a thermocline and the surface layer’s stability are essential factors for initiating winter blooms of coccolithophores. It was noted that after the winter blooms of coccolithophores, their summer growth was poorly expressed. It is shown that during periods of rapid growth, the bulk of coccolithophores is concentrated in the upper mixed layer and thermocline. During the blooming period, the share of coccolithophores in phytoplankton biomass constituted 70–85%. The intensity of coccolithophore’s blooms is associated with the previous diatoms’ growth level. The effect of eddies circulation on the distribution and growth of coccolithophores is considered.

Active Faulting of Landforms along the Tuosuhu-Maoniushan Fault and Its Seismotectonic Implications in Eastern Qaidam Basin, China

The fold-and-thrust belt along the northern margin of the Qaidam basin is a typical active tectonic belt located in the northeast Tibetan Plateau. This belt is at a high risk of strong earthquakes with magnitudes larger than 6, as shown by multiple recorded events during 1962–2009. The lack of detailed late Quaternary surficial faulting data and systematic seismotectonic studies has posed difficulties in properly assessing the seismic risks and understanding the ongoing geodynamics in this region. In this study, we mapped the geomorphic features and fault traces from high-resolution satellite images and field investigations of the Tuosuhu-Maoniushan fault (TMF). Field photogrammetry was conducted to obtain deformation measurements using a DJI M300 real-time kinematic (RTK) drone. The TMF displaces the Holocene and late Pleistocene alluvial terraces in the eastern Qaidam basin. This fault dips to the south in the west and central segments (as a boundary of the Denan depression) and to the north in the eastern segment along the piedmont of the Maoniushan Mountains. The vertical slip rate is estimated to be 0.37 ± 0.08 mm/yr, which is similar to that of the active southern Zongwulongshan fault. By integrating our investigations with the previously published studies on deep structures and Cenozoic geology of the region, we propose a deep-seated thrust model for the seismotectonics of the northern margin of the Qaidam basin. The Aimunike, Tuosuhu-Maoniushan, southern Zongwulongshan, and Zongwulong faults, along with many folds, form an active compressional zone. The complex across-strike structures and along-strike segmentation could facilitate the release of strain through earthquakes of magnitude 6–7 in this broad seismotectonics belt, rather than through strong surface-rupturing events resulting from a single mature large fault.

A cluster-based multiparametric similarity test for the compartmentalization of crystalline rocks into structural domains

Usually, fracture sampling studies comprise the collection of several fracture samples, which involve many fracture clusters. Grouping fracture samples into structural domains is generally useful for geologists, hydrogeologists, and geomechanicians as a region of fractured rocks is subdivided into sub-regions with similar behavior in terms of their hydromechanical properties. One of the common methods used for grouping fracture samples into structural domains considers the fracture orientation of clusters and ignores several fracture parameters, such as fracture spacing, aperture, and persistence, which are important for fluid circulation in the rock mass.In this study, we proposed a new cluster-based similarity method that considered the orientation of clusters as well as clusters’ aperture, persistence, and fracture spacing. Field investigations were conducted in the Grenville geological province of the Canadian Shield in the Lanaudière region, Quebec, Canada, where fractures were sampled from 30 outcrops and four boreholes. The proposed method is more suitable than other methods, and has applications in hydrogeology, rock mechanics, and especially in studies of fluid circulation in the rock mass. In addition, a method for the compartmentalization of a given study area into structural domains by means of Voronoi diagrams was also proposed.

Field Evaluation of High Modulus Asphalt Concrete Resistance to Low-Temperature Cracking

High-modulus asphalt concrete has numerous advantages in comparison to conventional asphalt concrete, including increased resistance to permanent deformations and increased pavement fatigue life. However, previous studies have shown that the construction of road pavements with High Modulus Asphalt Concrete (HMAC) may significantly increase the risk of low-temperature cracking. Those observations were the motivation for the research presented in this paper. Four test sections with HMAC used in base and binder courses were evaluated in the study. Field investigations of the number of low-temperature cracks were performed over several years. It was established that the number of new low-temperature cracks is susceptible to many random factors, and the statistical term “reversion to the mean” should be considered. A new factor named Increase in Cracking Index was developed to analyze the resistance of pavement to low-temperature cracking. For all the considered field sections, samples were cut from each asphalt layer, and Thermal Stress Restrained Specimen Tests were performed in the laboratory. Correlations of temperature at failure and cryogenic stresses with the cracking intensity observed in the field were analyzed. The paper provides practical suggestions for pavement designers. When the use of high modulus asphalt concrete is planned for binder course and asphalt base, which may result in lower resistance to low-temperature cracking of pavement than in the case of conventional asphalt concrete, it is advisable to apply a wearing course with improved resistance to low-temperature cracking. Such an approach may compensate for the adverse effects of usage of high modulus asphalt concrete.

Optimized Spacing Of The Longitudinal Reinforcement In CRCP To Avoid Horizontal Cracking

Continuously reinforced concrete pavement (CRCP) is characterized by the absence of transverse contraction joints and the presence of longitudinal and transverse reinforcement. The continuous longitudinal reinforcement holds the transverse cracks, caused by the longitudinal shrinkage of concrete, tightly together and thus provides long term performance with minimal maintenance cost. Field investigations on recently constructed CRCP's in Flanders region of Belgium indicated horizontal cracking in the vicinity of the longitudinal reinforcement under the transverse cracks which eventually causes the punch-out distress at the edge of the pavement slab. This paper shows the results of a finite element (FE) study to investigate the effect of varying longitudinal reinforcement on the risk of horizontal cracking in CRCP under typical Flanders conditions. For this purpose, a (3D) FE model of CRCP is developed using a FE package Diana 10.2. The varying longitudinal reinforcement with a most narrow spacing of 125mm in the outer region of the pavement slab is applied while keeping the same CRCP reinforcement ratio. A comparison is made with the conventional longitudinal reinforcement spacing (170mm). Development of concrete stress in the vicinity of the longitudinal reinforcement is plotted against the different longitudinal steel spacing. Findings show that the stress in concrete near longitudinal reinforcement is significantly reduced up to maximum 17% when the narrow spacing is used. In addition, the steel stress in the longitudinal reinforcing is reduced up to maximum 31.75% in the outer region of the pavement slab.

A Study to Verify the Practicality of Introducing an Arson Dog (K-9) Unit in Field Investigations

Combustion improvers are often found in acts of arson. Until recently, in fire investigations in Korea, these substances have been identified only by the olfactory sense of the fire inspectors or conventional gas detectors. These methods are neither efficient nor feasible in damaged buildings or large areas. Research on the canine sense of smell has shown that a dog can distinguish the remains of combusted hydrocarbon compounds, even in a large, open area. Field tests confirmed that arson dogs can find combustion improvers at fire sites in about five to 77 s. Therefore, this study verified the practicality of introducing arson dog units in field investigations of fire sites to identify combustion improvers sprayed for committing arson.

THE URBAN PROFILES OF PEACE TOURISM IN ARAB CITIES: OPPORTUNITIES FOR CHANGE TOWARDS SUSTAINABILITY. CASE STUDY: AS-SALT (JORDAN) AND CONSTANTINE (ALGERIA) CITIES

Tourism is not only considered as a stimulator for the social and economic development for countries, but also it contributes in spreading peace and enhancing negotiation, comprehension, and exchanging cultures among people in the light of the increased tourist demand. Arab countries confronted fluctuation and instability in the number of tourist arrivals due to security disturbances, conflicts and the vanishing of peace opportunities. In this regard, this research reveals the urban features for some Arab countries in achieving peace tourism because it is considered as touristic destinations that enhance heritage tourism due to the existence of the whole touristic features. The study sheds the lights on both As-Salt (Jordan) and Constantine (Algeria) cities. For the purpose of highlighting the opportunities of peace tourism by its urban features for changing towards sustainability by adopting that combine tourism development, peace building, and heritage conservation in both Arab cities. The researchers also required the development of certain tactical techniques to attain clear results in the research, the study relied on qualitative research in reviewing many documents and research related to both tourism and peace. In addition, field investigations contributed to providing data and information during the period from (2015-2018), like that the observation and interviews conducted with the local community in both cities. Results of the research, represented mainly in the presence of opportunities for peace tourism, which are reinforced by the specificity of the urban characteristics of the two cities, and its clear role in establishing a culture of peace, understanding, dialogue and exchange of cultures, which requires defining a model for the relationship between the development of tourism, peace and heritage in the cities of Salt and Constantine and which is based on tourism planning with the effective participation of different stakeholders.

Investigation and Analysis of the Current Situation of Olive-Stone Carving Inheritance in Guangzhou

The issue of inheriting and developing traditional handicrafts in this contemporary society is being explored by all walks of life in China. Taking the olive-stone carving in Guangzhou as a case, field investigations and analyses of its current situation of inheritance have been conducted. It has been found that although the government in Guangzhou has been paying more attention to olive-stone carving, there are still many problems, including the shortage of raw materials, no inheritors, low market recognition, and inadequate promotion. Therefore, the local government has cooperated with schools and craftsmen to search for key solutions in regard to raw material protection, training of inheritors, product development, and product promotion.

A Summary of Studies on Bon and Its Relationship with Buddhism

Bon Religion is the original religion of the Qinghai-Tibet Plateau. Today there are still Bon beliefs or cultural phenomena influenced by Bon Religion in areas where Tibetans live. This is an important content of Tibetology research today. Predecessors’ research on Bon Religion mainly focused on three major issues: the birth of Bon Religion, the historical staging of Bon Religion, and the relationship between Buddhism and Ben religion. Many results have been achieved. However, these are far from enough in terms of the research value of Bon Religion itself. The research on the time and place of the birth of Bon Religion has not yet been concluded. The main results are concentrated on the research of macroscopic issues, and the research on specific issues is insufficient. In response to these issues, researchers should pay attention to the re-discussion of existing results, use the method of combining literature and field investigations to pay more attention to specific regional issues, and at the same time strengthen the use of multiple languages.