Following its pioneering application in the present LHCb Velo detector, CO2 evaporative cooling has become the consolidated technology for the thermal management of low-temperature operated silicon ...detectors at LHC. ATLAS Insertable B-Layer and CMS Phase I Pixel are successfully operating with such cooling system since a few years and LHCb has selected the same technology for the new Upstream Tracker and the upgraded Velo, both to be installed during LS2. The design of the ATLAS and CMS upgrade silicon detectors is well advanced, and both experiments heavily rely on CO2 evaporative cooling. In order to cope with the new detector requirements, several studies are on-going, in particular on the scaling of the cooling plants, their integration in the existing space and infrastructure, the low temperature operation. A demonstrator cooling system, the “Demo”, is presently in the design phase at CERN. This paper discusses the challenges of the CO2 systems for the phase 2 upgrade of the LHC experiments, the design of the “Demo” cooling system and the integration and operational issues under study, presenting a time-line for the CO2 system development from now up to operation.
ATLAS “Baby-DEMO” Zwalinski, L.; Bojdol, K.; Bortolin, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2019, Volume:
936
Journal Article
Peer reviewed
Open access
Evaporative CO2 has been selected as the main detector cooling technology for the Phase II upgrade of the LHC silicon detectors at CERN. In order to provide input to the ATLAS Pixel TDR about the ...minimum attainable cooling temperature by the end of 2017, ATLAS, with a contribution of CMS, has launched a dedicated detector cooling R&D study nick-named Baby-DEMO. The Baby-DEMO is the demonstration of a typical 2PACL CO2 cooling plant operating at the lowest temperature ever achieved. A real size ATLAS mock-up is used to hold realistic manifolding as its critical path might have strong impact on the cooling performance. Additionally, the “Baby-DEMO” program addresses the study of high power flexible vacuum insulated coaxial transfer lines and warm nose boiling enhancement as possible solutions for the Phase II upgrade. This paper describes the system design including CO2 plant, primary chiller and typical distribution. Challenges and solutions used to achieve the lowest possible evaporation temperatures are reported. The result of this study, even if at the preliminary stage, are of great interest for the design of the cooling systems that ATLAS and CMS will use in the Phase II era.
•Target minimum cooling evaporator temperature achieved, 5kW @ <−40°C at dummy load•Larger than expected temperature gradients observed in flex lines.•Stable long term operation at −47°C accumulator cooling.•Record low temperature of −50°C achieved with manual tricks.
In the frame of the progress towards the High Luminosity Program of the Large Hadron Collider at CERN, the ATLAS and CMS experiments are boosting the preparation of their new environmental friendly ...low temperature detector cooling systems. This paper will present a general overview of the progress in development and construction of the future CO2 cooling systems for silicon detectors at ATLAS and CMS (trackers, calorimeters and timing layers), due for implementation during the 3rd Long Shut Down of LHC (LS3). We will describe the selected technology for the primary chillers, based on an innovative transcritical cycle of R744 (refrigerant grade CO2) as coolant, and the oil-free secondary “on detector” CO2 pumped loop, based on the evolution of the successful 2 Phase Accumulator Control Loop (2PACL) concept. Different detector layers will profit from an homogenized infrastructure and will share multi-level redundancy that we will describe in details. The technical progresses achieved by the EP-DT group at CERN over the last years will be discussed in view of the challenges and key solutions developed to cope with the unprecedented scale of the systems. We will finally present how mechanics- and controls-related problems have been addressed via a vigorous prototyping programme, aiming at cost- and resource-effective construction of the final systems, which is starting now.
Protected areas not allowing extractive activities (here called fully protected area) are a spatially explicit conservation management tool commonly used to ensure populations persistence. This is ...achieved when an adequate fraction of a species' population spends most of its time within the boundaries of the protected area. Within a marine context, home ranges represent a tractable metric to provide guidance and evaluation of fully protected areas. We compiled peer-reviewed literature specific to the home ranges of finfishes and invertebrates of ecological and/or commercial importance in the Mediterranean Sea, and related this to the size of 184 Mediterranean fully protected areas. We also investigated the influence of fully protected areas size on fish density in contrast to fished areas with respect to home ranges. Home range estimations were available for 11 species (10 fishes and 1 lobster). The European spiny lobster Palinurus elephas had the smallest home range (0.0039 ± 0.0014 km2; mean ± 1 SE), while the painted comber Serranus scriba (1.1075 ± 0.2040 km2) had the largest. Approximately 25% of Mediterranean fully protected areas are larger than 2 times the size of the largest home range recorded. Fish densities were significantly higher when fully protected areas were larger than the home range, while no change in density occurred when home ranges were larger than fully protected areas. These results display a direct link between the effectiveness of fully protected areas and species' home range, suggesting that fully protected areas of at least 3.6 km2 may increase the density of local populations of these coastal marine species.
•European spiny lobster had the smallest home range, painted comber had the largest.•Fish density was higher in protected areas larger than the species' home ranges.•No-take zones of at least 3.6 km2 can increase density of local populations.•Network of no-take zones covering ≥1.7% of coastal areas could benefits species.
Spatial representations of threatening processes - "threat maps" - can identify where biodiversity is at risk, and are often used to identify priority locations for conservation. In doing so, ...decision makers are prone to making errors, either by assuming that the level of threat dictates spatial priorities for action or by relying primarily on the location of mapped threats to choose possible actions. We show that threat mapping can be a useful tool when incorporated within a transparent and repeatable structured decision-making (SDM) process. SDM ensures transparent and defendable conservation decisions by linking objectives to biodiversity outcomes, and by considering constraints, consequences of actions, and uncertainty. If used to make conservation decisions, threat maps are best developed with an understanding of how species respond to actions that mitigate threats. This approach will ensure that conservation actions are prioritized where they are most cost-effective or have the greatest impact, rather than where threat levels are highest.
The European Union (EU) has committed to an ambitious biodiversity recovery plan in its Biodiversity Strategy for 2030 and the Green Deal. These policies aim to halt biodiversity loss and move ...towards sustainable development, focusing on restoring degraded habitats, extending the network of protected areas (PAs), and improving the effectiveness of management, governance, and funding. The achievement of conservation goals must be founded on understanding past successes and failures. Here, we summarise the strengths and weaknesses of past EU biodiversity conservation policies and practices and explore future opportunities and challenges. We focus on four main aspects: i) coordination among and within the EU Member States, ii) integration of biodiversity conservation into socio-economic sectors, iii) adequacy and sufficiency of funds, and iv) governance and stakeholder participation.Whilst past conservation efforts have benefitted from common rules across the EU and funding mechanisms, they have failed at operationalizing coordination within and across the Member States, integrating biodiversity conservation into other sectoral policies, adequately funding and effectively enforcing management, and facilitating stakeholder participation in decision-making. Future biodiversity conservation would benefit from an extended and better-managed network of PAs, additional novel funding opportunities, including the private sector, and enhanced co-governance. However, it will be critical to find sustainable solutions to potential conflicts between conservation goals and other socio-economic objectives and to resolve inconsistencies across sectoral policies.
•The European Union needs more effective conservation as biodiversity declines.•Past success/ failure should guide the implementation of the Biodiversity Strategy.•Better integration of conservation policy into socioeconomic sectors is needed.•More funds, management plans and stakeholder participation are also key.•Adequate planning should guide future efforts to minimise conflicts between sectors.
The United Arab Emirates (UAE) host valuable coastal and marine biodiversity that is subjected to multiple pressures under extreme conditions. To mitigate impacts on marine ecosystems, the UAE ...protects almost 12% of its Exclusive Economic Zone. This study mapped and validated the distribution of key coastal and marine habitats, species and critical areas for their life cycle in the Gulf area of the UAE. We identified gaps in the current protection of these ecological features and assessed the quality of the data used. The overall dataset showed good data quality, but deficiencies in information for the coastline of the north-western emirates. The existing protected areas are inadequate to safeguard key ecological features such as mangroves and coastal lagoons. This study offers a solid basis to understand the spatial distribution and protection of marine biodiversity in the UAE. This information should be considered for implementing effective conservation planning and ecosystem-based management.
•Mapping species and habitats is necessary for effective ecosystem-based management.•We compiled data to map marine and coastal biodiversity distribution in the UAE.•Data quality assessment showed that data are sufficient to guide management.•Current MPA extension is insufficient to safeguard some habitats such as mangroves.•The information provided should be used in future conservation plans and management.
Morphological similarity between an intruder and a native species can hinder the detection of the intruder. The undetected non-native species will thus have more time to affect the local ecosystem ...and spread. This paper describes an instance of unnoticed introduction of a fish species morphologically resembling a native endemic species. We report on the first established population of the Rhodes minnow, Ladigesocypris ghigii (Actinopterygii: Leuciscidae), endemic to Rhodes Island, which has been recently introduced to a river near Athens, mainland Greece. When it was first noticed, in 2017, the species was misidentified due to its morphological similarity to Pelasgus marathonicus, the only native leuciscid of the streams and rivers around Athens, until it was subject to genetic and detailed morphological examination. Genetic analyses based on both mitochondrial (cytochrome b) and nuclear (recombination activating gene, RAG1) markers unambiguously identified the collected individuals and provided information on the relationships of Ladigesocypris at both the species and generic level. Our investigation supports that L. ghigii was recently established near Athens, and that the population probably originated from Rhodes Island, an eastern Aegean island. In 2021, a high-density thriving mainland population coexisted solely with the native European eel (Anguilla anguilla) along at least 9.7 km of river habitat. It was assessed as being of high invasive risk for the region where it was established by the Aquatic Species Invasiveness Screening Kit (AS-ISK) screening tool. We propose a feasibility study be undertaken to investigate the application of measures that may include actions to exterminate or contain the population. Special attention is required since the species is considered vulnerable in its native range, while the translocated population coexists with native biota within a stream ecosystem of outstanding local conservation value.
Marine protected areas (MPAs) are a cornerstone of marine conservation. Globally, the number and coverage of MPAs are increasing, but MPA implementation lags in many human-dominated regions. In areas ...with intense competition for space and resources, evaluation of the effects of MPAs is crucial to inform decisions. In the human-dominated Mediterranean Sea, fully protected areas occupy only 0.04% of its surface. We evaluated the impacts of full and partial protection on biomass and density of fish assemblages, some commercially important fishes, and sea urchins in 24 Mediterranean MPAs. We explored the relationships between the level of protection and MPA size, age, and enforcement. Results revealed significant positive effects of protection for fisheries target species and negative effects for urchins as their predators benefited from protection. Full protection provided stronger effects than partial protection. Benefits of full protection for fish biomass were only correlated with the level of MPA enforcement; fish density was higher in older, better enforced, and -interestingly- smaller MPAs. Our finding that even small, well-enforced, fully protected areas can have significant ecological effects is encouraging for "crowded" marine environments. However, more data are needed to evaluate sufficient MPA sizes for protecting populations of species with varying mobility levels.
Abstract
The Natura 2000 network forms the cornerstone of the biodiversity conservation strategy of the European Union and is the largest coordinated network of protected areas (PAs) in the world. ...Here, we demonstrated that the network fails to adequately cover the marine environment and meet the conservation target of 10% set by the Convention on Biological Diversity. The relative percentage of marine surface cover varies significantly among member states. Interestingly, the relative cover of protected seascape was significantly lower for member states with larger exclusive economic zones. Our analyses demonstrated that the vast majority (93%) of the Natura 2000 sites that cover marine waters include both a terrestrial and a marine component. As a result, the majority of the protected surfaces is adjacent to the coastline, and decreases offshore; only 20% of Natura marine PAs is at depths >200 m. The lack of systematic planning processes is further reflected by the great variability in the distances among protected sites and the limited number of shared Natura sites among member states. Moreover, <40% of the marine sites have management plans, indicating the absence of active, or limited management in most sites. This work highlights the gaps in coverage and spatial design of the European conservation network in the marine environment, and raises questions on the unevenly treatment of marine vs. terrestrial areas.
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