scholarly journals Data-Driven Recommendations for Establishing Threshold Values for the NIS Trend Indicator in the Mediterranean Sea

Diversity ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 57
Author(s):  
Marika Galanidi ◽  
Argyro Zenetos
Keyword(s):  
Time Series Data ◽  
Driving Forces ◽  
Eastern Mediterranean ◽  
Time Lag ◽  
Series Data ◽  
Indigenous Species ◽  
Reference Period ◽  
Threshold Values ◽  
Basin Scale ◽  
The Mediterranean

In the present work, we analysed time series data on the introduction of new non-indigenous species (NIS) in the Mediterranean between 1970 and 2017, aiming to arrive at recommendations concerning the reference period and provisional threshold values for the NIS trend indicator. We employed regression analysis and breakpoint structural analysis. Our results confirm earlier findings that the reference conditions differ for the four Mediterranean subregions, and support a shortening of the reporting cycle from six to three years, with a two-year time lag for the ensuing assessment. Excluding Lessepsian fishes and parasites, the reference period, defined as the most recent time segment with stable mean new NIS values, was estimated as 1997–2017 for the eastern Mediterranean, 2012–2017 for the central Mediterranean, 2000–2017 for the Adriatic and 1970–2017 for the western Mediterranean. These findings are interpreted primarily on the basis of a basin scale temperature regime shift in the late 1990s, shifts in driving forces such as shellfish culture, and as a result of intensified research efforts and citizen scientist initiatives targeting NIS in the last decade. The threshold values, i.e., the three-year average new NIS values during the reference period, are indicative and will ultimately depend on the choice of species and pathways to be used in the calculations. This is discussed through the prism of target setting in alignment with specific management objectives.

scholarly journals Fisheries in the Mediterranean

2000 ◽  
Vol 1 (1) ◽  
pp. 5 ◽  
Author(s):  
C. PAPACONSTANTINOU ◽  
H. FARRUGIO
Keyword(s):  
Time Series Data ◽  
Early Stage ◽  
Eastern Mediterranean ◽  
Fishing Effort ◽  
Series Data ◽  
Small Scale ◽  
General Description ◽  
Stage Of Development ◽  
Mediterranean Countries ◽  
The Mediterranean

The aim of this paper is to give a description of the Mediterranean fisheries, and its level of exploitation and to address the main questions dealing with its management. The Mediterranean is a semi-enclosed marine area with generally narrow continental shelves. The primary production of the Mediterranean is among the lowest in the world (26-50g C m-2 y-1). The Mediterranean fisheries can be broken down into three main categories: small scale fisheries, trawling and seining fisheries, which operated on demersal, small pelagic and large pelagic resources. After a general description of the state of the resources in the different areas of the Mediterranean it is concluded that (a) the overall pictures from the western to the eastern Mediterranean are not considerably different, (b) the total landings in the Mediterranean have been increased the last decades, and (c) from the perspective of stock assessment, the very few available time series data show stable yield levels. In general fisheries management in the Mediterranean is at a rela- tively early stage of development, judging by the criteria of North Atlantic fisheries. Quota systems are generally not applied, mesh-size regulations usually are set at low levels relative to scientific advice, and effort limitation is not usually applied or, if it is, is not always based on a formal resource assessment. The conservation/management measures applied by the Mediterranean countries can be broadly separated into two major categories: those aiming to keep the fishing effort under control and those aiming to make the exploitation pattern more rational. The most acute problems in the management of the Mediterranean resources are the multispecificity of the catches and the lack of reliable official statistics.

scholarly journals Low diversity or poorly explored? Mesophotic molluscs highlight undersampling in the Eastern Mediterranean

2020 ◽  
Vol 29 (14) ◽  
pp. 4059-4072
Author(s):  
Paolo G. Albano ◽  
Michele Azzarone ◽  
Bruno Amati ◽  
Cesare Bogi ◽  
Bruno Sabelli ◽  
...  
Keyword(s):  
Eastern Mediterranean ◽  
Rocky Reef ◽  
Indigenous Species ◽  
Diversity Gradient ◽  
Conservation Actions ◽  
The Mediterranean ◽  
Molluscan Diversity ◽  
Vulnerable Habitats ◽  
Non Indigenous Species ◽  
Recreational Scuba

Abstract Mesophotic assemblages are the next frontier of marine exploration in the Mediterranean Sea. Located below recreational scuba diving depths, they are difficult to access but host a diverse array of habitats structured by large invertebrate species. The Eastern Mediterranean has been much less explored than the western part of the basin and its mesophotic habitats are virtually unknown. We here describe two mesophotic (77–92 m depth) molluscan assemblages at a rocky reef and on a soft substrate off northern Israel. We record 172 species, of which 43 (25%) are first records for Israel and increase its overall marine molluscan diversity by 7%. Only five of these species have been reported in recent surveys of the nearby Lebanon, suggesting that our results are robust at a broader scale than our study area and that the reported west-to-east declining diversity gradient in the Mediterranean needs a reappraisal based on proper sampling of the eastern basin. We found only four (2%) non-indigenous species, represented by seven (0.5%) specimens. These results suggest that pristine native assemblages still thrive at this depth in Israel, in contrast to the shallow subtidal heavily affected by global warming and biological invasions, calling for strong conservation actions for these valuable but vulnerable habitats.

The impacts of China’s FDI on employment in Thailand’s industrial sector

2016 ◽  
Vol 9 (1) ◽  
pp. 60-84 ◽  
Author(s):  
Mathavee Keorite ◽  
Mohamed Moubarak
Keyword(s):  
Time Series Data ◽  
Driving Forces ◽  
Dominant Role ◽  
Government Expenditure ◽  
Impulse Response Function ◽  
Industrial Sector ◽  
Series Data ◽  
Content Type ◽  
Reduction Potentials ◽  
Industrial Sectors

Purpose – This study aims to analyze the effect of inward foreign direct investment (FDI) on new job creation. This study pays attention to factors interrelated to China’s FDI by using the case of Thailand. Design/methodology/approach – Using time series data from 2001 to 2014, this paper explores the driving forces and reduction potentials of employment in Thailand’s industrial sector with consideration for dynamic changes within the vector autoregression model. Findings – The results show that government expenditure plays a dominant role in increasing employment in Thailand’s industrial sector and exports plays a dominant role in decreasing employment in Thailand’s industrial sector. All variables are co-integrated and the analysis of the impulse–response function also turns out to be synchronous. Furthermore, in the short term, exports are more critical than China’s FDI in industrial sectors in reduction potentials of employment in Thailand’s industrial. Practical/implications – Policies should be devised to increase skilled labour and improve the equality of infrastructure in the country to attract more FDI into the economy and for quick adjustment purposes in case of shock to the system. Originality/value – The paper uncovers some important factors influencing employment in Thailand’s industrial sector under study and provides a guide-map for policymakers.

scholarly journals Multiscale monsoon variability during the last two climatic cycles inferred from Chinese loess and speleothem records

2014 ◽  
Vol 10 (6) ◽  
pp. 4623-4646
Author(s):  
Y. Li ◽  
N. Su ◽  
L. Liang ◽  
L. Ma ◽  
Y. Yan ◽  
...  
Keyword(s):  
Grain Size ◽  
North Atlantic ◽  
Time Series Data ◽  
Driving Forces ◽  
East Asian Monsoon ◽  
Series Data ◽  
Chinese Loess ◽  
Ice Volume ◽  
Climatic Cycles ◽  
Monsoon Variability

Abstract. The East Asian Monsoon exhibits a significant variability on timescales ranging from tectonic to centennial as inferred from Chinese loess, stalagmite and marine records. However, the relative contributions and plausible driving forces of the signals at different timescales remain poorly investigated. Here, we spectrally decompose time series data on loess grain size and speleothem δ18O records over the last two climatic cycles and correlate the decomposed components with possible driving parameters including the ice volume, insolation and North Atlantic cooling. Based on the spectral analysis of these two proxies, we tentatively identified six components of the signals corresponding to various forcing of ice volume (> 50 kyr), obliquity (50–30 kyr), precession (30–9 kyr), North Atlantic cooling (9–3 kyr and 3–1 kyr), and a centennial residual. The relative contributions of each component differ significantly between loess grain size and speleothem δ18O records. Glacial and orbital components are dominant in the loess grain size, which implies that both ice volume and insolation have distinctive impacts on the winter monsoon variability in contrast to the predominant precession impact on the summer monsoon patterns. Moreover, the millennial components are evident with variances of 11 and 16% in the loess grain size and speleothem δ18O records, respectively. A comparison of the millennial-scale signals in these two proxies reveals that abrupt changes in the winter and summer monsoons over the last 260 kyr share common features and similar driving forces linked to high-latitude Northern Hemisphere climate.

scholarly journals Seasonal ecosystem vulnerability to climatic anomalies in the Mediterranean

2021 ◽  
Author(s):  
Johannes Vogel ◽  
Eva Paton ◽  
Valentin Aich
Keyword(s):  
Soil Moisture ◽  
Eastern Mediterranean ◽  
Time Lag ◽  
Mediterranean Ecosystems ◽  
Western Mediterranean ◽  
Bivariate Analysis ◽  
Spatial And Temporal Variability ◽  
Ecosystem Vulnerability ◽  
Dry Conditions ◽  
The Mediterranean

Abstract. Mediterranean ecosystems are particularly vulnerable to climate change and the associated increase in climate extremes. This study investigates extreme ecosystem responses evoked by climatic drivers in the Mediterranean Basin for the time span 1999–2019 with a specific focus on seasonal variations, as the seasonal timing of climatic anomalies is considered essential for impact and vulnerability assessment. A bivariate vulnerability analysis is performed for each month of the year to quantify which combinations of the drivers temperature (obtained from ER5 Land) and soil moisture (obtained from ESA CCI and ERA5 Land) lead to extreme reductions of ecosystem productivity using the fraction of absorbed photosynthetically active radiation (FAPAR; obtained from Copernicus Global Land Service) as a proxy. The bivariate analysis clearly showed that, in many cases, it is not just one but a combination of both drivers that causes ecosystem vulnerability. The overall pattern shows that Mediterranean ecosystems are prone to three soil moisture regimes during the yearly cycle: They are vulnerable to hot and dry conditions from May to July, to cold and dry conditions from August to October, and to cold conditions from November to April, illustrating the shift from a soil moisture-limited regime in summer to an energy-limited regime in winter. In late spring, a month with significant vulnerability to hot conditions only often precedes the next stage of vulnerability to both hot and dry conditions, suggesting that high temperatures lead to critically low soil moisture levels with a certain time lag. In the eastern Mediterranean, the period of vulnerability to hot and dry conditions within the year is much longer than in the western Mediterranean. Our results show that it is crucial to account for both spatial and temporal variability to adequately assess ecosystem vulnerability. The seasonal vulnerability approach presented in this study helps to provide detailed insights regarding the specific phenological stage of the year in which ecosystem vulnerability to a certain climatic condition occurs.

scholarly journals Seasonal ecosystem vulnerability to climatic anomalies in the Mediterranean

2021 ◽  
Vol 18 (22) ◽  
pp. 5903-5927
Author(s):  
Johannes Vogel ◽  
Eva Paton ◽  
Valentin Aich
Keyword(s):  
Soil Moisture ◽  
Eastern Mediterranean ◽  
Time Lag ◽  
Mediterranean Ecosystems ◽  
Western Mediterranean ◽  
Bivariate Analysis ◽  
Spatial And Temporal Variability ◽  
Ecosystem Vulnerability ◽  
Dry Conditions ◽  
The Mediterranean

Abstract. Mediterranean ecosystems are particularly vulnerable to climate change and the associated increase in climate anomalies. This study investigates extreme ecosystem responses evoked by climatic drivers in the Mediterranean Basin for the time span 1999–2019 with a specific focus on seasonal variations as the seasonal timing of climatic anomalies is considered essential for impact and vulnerability assessment. A bivariate vulnerability analysis is performed for each month of the year to quantify which combinations of the drivers temperature (obtained from ERA5-Land) and soil moisture (obtained from ESA CCI and ERA5-Land) lead to extreme reductions in ecosystem productivity using the fraction of absorbed photosynthetically active radiation (FAPAR; obtained from the Copernicus Global Land Service) as a proxy. The bivariate analysis clearly showed that, in many cases, it is not just one but a combination of both drivers that causes ecosystem vulnerability. The overall pattern shows that Mediterranean ecosystems are prone to three soil moisture regimes during the yearly cycle: they are vulnerable to hot and dry conditions from May to July, to cold and dry conditions from August to October, and to cold conditions from November to April, illustrating the shift from a soil-moisture-limited regime in summer to an energy-limited regime in winter. In late spring, a month with significant vulnerability to hot conditions only often precedes the next stage of vulnerability to both hot and dry conditions, suggesting that high temperatures lead to critically low soil moisture levels with a certain time lag. In the eastern Mediterranean, the period of vulnerability to hot and dry conditions within the year is much longer than in the western Mediterranean. Our results show that it is crucial to account for both spatial and temporal variability to adequately assess ecosystem vulnerability. The seasonal vulnerability approach presented in this study helps to provide detailed insights regarding the specific phenological stage of the year in which ecosystem vulnerability to a certain climatic condition occurs.

scholarly journals Spatiotemporal variability of alkalinity in the Mediterranean Sea

2015 ◽  
Vol 12 (6) ◽  
pp. 1647-1658 ◽  
Author(s):  
G. Cossarini ◽  
P. Lazzari ◽  
C. Solidoro
Keyword(s):  
Mediterranean Sea ◽  
Seasonal Cycle ◽  
Sea Water ◽  
Eastern Mediterranean ◽  
Surface Flux ◽  
Spatiotemporal Variability ◽  
The Black Sea ◽  
Biogeochemical Model ◽  
Basin Scale ◽  
The Mediterranean

Abstract. The paper provides a basin-scale assessment of the spatiotemporal distribution of alkalinity in the Mediterranean Sea. The assessment is made by integrating the available observations into a 3-D transport–biogeochemical model. The results indicate the presence of complex spatial patterns: a marked west-to-east surface gradient of alkalinity is coupled to secondary negative gradients: (1) from marginal seas (Adriatic and Aegean Sea) to the eastern Mediterranean Sea and (2) from north to south in the western region. The west–east gradient is related to the mixing of Atlantic water entering from the Strait of Gibraltar with the high-alkaline water of the eastern sub-basins, which is correlated to the positive surface flux of evaporation minus precipitation. The north-to-south gradients are related to the terrestrial input and to the input of the Black Sea water through the Dardanelles. In the surface layers, alkalinity has a relevant seasonal cycle (up to 40 μmol kg−1) that is driven by physical processes (seasonal cycle of evaporation and vertical mixing) and, to a minor extent, by biological processes. A comparison of alkalinity vs. salinity indicates that different regions present different relationships: in regions of freshwater influence, the two quantities are negatively correlated due to riverine alkalinity input, whereas they are positively correlated in open sea areas of the Mediterranean Sea.

Holocene fish assemblages provide baseline data for the rapidly changing eastern Mediterranean

The Holocene ◽  
2020 ◽  
Vol 30 (10) ◽  
pp. 1438-1450
Author(s):  
Konstantina Agiadi ◽  
Paolo G Albano
Keyword(s):  
Radiocarbon Dating ◽  
Trophic Structure ◽  
Fish Assemblages ◽  
Eastern Mediterranean ◽  
Marine Ecosystem ◽  
Fish Fauna ◽  
Suez Canal ◽  
Indigenous Species ◽  
The Mediterranean ◽  
Non Indigenous Species

The eastern Mediterranean marine ecosystem is undergoing massive modification due to biological invasions, overfishing, habitat deterioration, and climate warming. Our ability to quantify these changes is severely hindered by the lack of an appropriate baseline; most ecological datasets date back a few decades only and show already strong signatures of impact. Surficial death assemblages (DAs) offer an alternative data source that provides baseline information on community structure and composition. In this study, we reconstruct the marine fish fauna of the southern shallow Israeli shelf before the opening of the Suez Canal based on fish otoliths. We quantify the age of the otolith DAs by radiocarbon dating, and describe its taxonomic composition, geographic affinity, and trophic structure. Additionally, we test by radiocarbon dating the hypothesis that Bregmaceros, a presumed Lessepsian invader with continuous presence in the Mediterranean throughout the late Cenozoic, is a relict species. The otolith DA dates back to the mid-Holocene because 75% of the dated otoliths of the native species are older than the opening of the Suez Canal in 1869, suggesting that the DA is a proper baseline for quantifying modern impacts. Consistently, 97% of the otoliths and 88% of the species we collected belong to native Mediterranean species. The native anchovy Engraulis encrasicolus dominates the DAs, although gobiids are the most diverse group (14 species, 28%). The DAs show similar trophic structure to present-day pristine Mediterranean coastal fish assemblages. Two non-indigenous species are recorded here for the first time in the Mediterranean Sea, Amblygobius albimaculatus and Callogobius sp., highlighting the importance of DAs for detecting non-indigenous species. Finally, Bregmaceros otoliths are modern, not supporting the previous hypothesis that the taxon is a Pleistocene relict.

scholarly journals Indigenous versus Lessepsian Hosts: Nervous Necrosis Virus (NNV) in Eastern Mediterranean Sea Fish

Viruses ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 430 ◽  
Author(s):  
Yael Lampert ◽  
Ran Berzak ◽  
Nadav Davidovich ◽  
Arik Diamant ◽  
Nir Stern ◽  
...  
Keyword(s):  
Invasive Species ◽  
Mediterranean Sea ◽  
Marine Environment ◽  
Fish Species ◽  
Eastern Mediterranean ◽  
Nervous Necrosis Virus ◽  
Indigenous Species ◽  
Necrosis Virus ◽  
Marine Aquaculture ◽  
The Mediterranean

Viruses are among the most abundant and diverse biological components in the marine environment. In finfish, viruses are key drivers of host diversity and population dynamics, and therefore, their effect on the marine environment is far-reaching. Viral encephalopathy and retinopathy (VER) is a disease caused by the marine nervous necrosis virus (NNV), which is recognized as one of the main infectious threats for marine aquaculture worldwide. For over 140 years, the Suez Canal has acted as a conduit for the invasion of Red Sea marine species into the Mediterranean Sea. In 2016–2017, we evaluated the prevalence of NNV in two indigenous Mediterranean species, the round sardinella (Sardinella aurita) and the white steenbras (Lithognathus mormyrus) versus two Lessepsian species, the Randall’s threadfin bream (Nemipterus randalli) and the Lessepsian lizardfish (Saurida lessepsianus). A molecular method was used to detect NNV in all four fish species tested. In N. randalli, a relatively newly established invasive species in the Mediterranean Sea, the prevalence was significantly higher than in both indigenous species. In S. lessepsianus, prevalence varied considerably between years. While the factors that influence the effective establishment of invasive species are poorly understood, we suggest that the susceptibility of a given invasive fish species to locally acquired viral pathogens such as NVV may be important, in terms of both its successful establishment in its newly adopted environment and its role as a reservoir ‘host’ in the new area.

Transformation in Vegetation and Urban Sprawl in Gotan and Surrounding

2021 ◽  
pp. 111-124
Author(s):  
Rizwan Ahmad ◽  
Ramaraju Sudarshana
Keyword(s):  
Urban Sprawl ◽  
Vegetation Cover ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Time Series Data ◽  
Driving Forces ◽  
Landsat Tm ◽  
Series Data ◽  
Monitoring Frequency ◽  
Government Sector

The main driving forces associated with transformation of vegetation cover and urban sprawl, are undoubtedly climate change and human intervention. Finding the truth behind transformation of Gotan, Rajasthan Landsat TM/ETM+ data of the years 1987,1990, 1995, 2000, 2003, 2010, 2015, and 2018 were used. These time series data comprising total of nine scenes were selected to measure the urban and green cover transformation in the past four decades. Landsat TM/ETM+ data were used because it is inexpensive, with high monitoring frequency and covers large areas. The Normalized Difference Vegetation Index (NDVI) of 1987–2018, derived from the remote sensing dataset along with the application of statistical methods and GIS techniques, were used to quantify vegetation cover change. The results show that human-induced factors can explain most variations at sites with significant cover change. It has been a well-known fact that sustainable development presents a system in order to accomplish economic growth, bring about social justice, implement environmental awareness and most certainly the fortification of government sector.

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