Waterbirds as an ecological indicator for monitoring wetlands: an application to Tunisia

We propose a simple ecological index to monitor wetlands, based on interannual changes in waterbird numbers and the hydro-ecological characteristics of their wintering sites. This new method provides a simple tool applicable to most types of wetlands in northern Africa with comparable waterbird species and hydrological attributes. Scores of this ecological index are calculated through a four-steps approach: (1) discriminate prospected sites into different associations based on their hydro-ecological characteristics; (2) compute indicator values for each waterbird species considered to quantify the strength of species-habitat relationships in each wetland associations; (3) calculate the relative rate of temporal change in indicator species abundances between two sampling events (in our example 2001-2013 and 1970/2000); (4) compute the weighted sum across species of the product of these two metrics within a given wetlands association. The application of our index to the monitoring of Tunisian wetlands suggests the degradation of wintering lagoons and salt pans and coastal environments. Nevertheless, applying the index in floodplains and garaets tends to indicate improved overwintering conditions, especially for man-tolerant waterbird species. Our new index targets environmental stakeholders seeking for an efficient tool for biodiversity monitoring.Nous proposons dans ce travail un indice écologique pour la surveillance des zones humides tunisiennes, basé sur la variation des effectifs annuels moyens d’oiseaux d’eau. Ce nouvel outil offre une méthode applicable à la surveillance de toutes les catégories de zones humides du Nord de l’Afrique ayant des similitudes avifaunistiques et hydrologiques. Cet indice écologique se calcule en quatre étapes : (1) discriminer les zones humides en associations partageant des caractéristiques hydro-écologiques communes ; (2) déterminer la valeur indicatrice de chaque espèce sur ces différentes associations, quantifiant la relation d’une espèce à l’une des associations ; (3) calculer les variations temporelles des effectifs moyens de chacune de ces espèces entre deux périodes de suivi (dans notre cas 1970/2000 et 2001/2013) ; (4) calculer la somme pondérée des produits des deux métriques de toutes les espèces indicatrices pour chaque association. L’application de notre indice aux zones humides tunisiennes suggère une dégradation des conditions d’hivernage des lagunes et des sebkhas ainsi que des milieux côtiers. À l’inverse, les conditions d’hivernage dans les plaines inondées et les garaets semblent s’améliorer, notamment pour les espèces anthropophiles. Cette méthode de surveillance des zones humides constitue un nouvel outil de travail simple et efficace pour les professionnels de l’environnement

Estimating the total number of wintering waterbirds in Tunisia: period 2001/2002 to 2006/2007

Over the past decades, many waterbird populations have undergone rapid changes in numbers as well as in distribution. These continuing changes make it necessary to update population estimates on a regular basis. From this point of view, a regular mid-winter survey of wintering waterbirds was carried out in Tunisian wetlands. The overall objective of this paper is to record wintering population sizes for the period 2001–2002 to 2006-2007 and to identify waterbird indicator species relative to these Tunisian ecosystems. The preliminary analysis of the collected information enabled us to define the size and the actual status of wintering waterbird populations in Tunisia. A total richness of 106 species (3 common, 18 frequent and 85 rare ones), belonging to 23 families and 10 orders, was identified. The most abundant species, which accounted for about 90 % of the total abundance, were : Calidris alpina (18.7 %), Phoenicopterus ruber (13.6 %), Aythya ferina (11.4 %), Fulica atra (10.7 %), Tringa totanus (5.9 %), Larus michahellis (5.2 %), Larus genei (3.9 %), Anas penelope (3.7 %), Calidris minuta (3.5 %), Anas clypeata (2.2 %), Larus ridibundus (2.0 %), Charadrius alexandrinus (1.9 %), Phalacrocorax carbo (1.6 %), Vanellus vanellus (1.4 %), Pluvialis squatarola (1.3 %), Anas platyrhynchos (1.3 %), Anas crecca (1.3 %) and Numenius arquata (1.1 %). With an average of about 427 300 birds per year, Tunisian wetland areas play an important role in waterbird populations conservation due to their large habitats, high productivity and geographical position connecting European and African continents. Considering the Ramsar Criterions, a total of 20 sites appear as internationally important. Indeed, 3 sites individually and regularly held more than 20 000 birds and should be classified as internationally important : Kneiss islands (72 368 birds per year), Ichkeul National Park (91 587 birds per year), and sebkhat Sejoumi (29 276 birds per year). Together, these wetlands host about 45 % of the total national population sizes. Three other sites are also potentially important, recorded as hosting more than 20 000 wintering birds at least once : Kerkennah islands (16 608 birds per year), Jerba island (14 962 birds per year) and sebkhat Ariana (19 122 birds per year). The 1 % threshold for use in Ramsar Convention was met for 14 species (Sterna sandvicensis, Larus genei, Platalea leucorodia, Grus grus, Charadrius alexandrinus, Phoenicopterus ruber roseus, Pluvialis squatarola, Calidris minuta, Calidris alpina, Tringa totanus, Anser anser, Anas penelope, Aythya ferina and Fulica atra) and was exceeded in 10 wetlands. Among all species, 6 are globally threatened (Marmaronetta angustirostris, Aythya nyroca, Oxyura leucocephala, Gallinago media, Limosa lapponica and Larus audouinii) and were regularly observed in 10 sites. Application of the global ANOVA Kurskal-Wallis test to data relative to species richness, mean abundance and Hill (N1 and N2) diversity values reveals highly significant differences between the 8 wetland classes. However, the spatial organization of aquatic birds doesn’t reflect any clear gradient. The ANOSYM test discriminates two major associations : artificial versus natural habitats. The latter are themselves organized into 3 sub-associations according to permanence of water and marine influences. Despite these important carrying capacities of Tunisian wetlands, natural factors and human exploitation have greatly modified many of these ecosystems through habitat loss and fragmentation. Thus, it appears essential to use appropriate strategies, like indicator species method, to enhance the value of these areas for waterbird species, which are very sensitive to habitat changes. In the present case, based on the SIMPER analyses method, 15 species are indicators of the wetland status : Phoenicopterus ruber, Charadrius alexandrinus, Calidris alpina, Larus michahellis, Ardea cinerea, Bubulcus ibis, Ciconia ciconia, Vanellus vanellus, Grus grus, Phalacrocorax carbo, Larus genei, Fulica atra, Tachybaptus ruficollis, Aythya ferina, Podiceps cristatus and Anas platyrhynchos. Besides their fundamental interest and importance, results of the present study can be essential to the application of conservation programsDurant la période 2001/2002 à 2006/2007, les recensements hivernaux des oiseaux aquatiques réalisés dans 151 zones humides tunisiennes révèlent une richesse spécifique totale de 106 espèces. L'ensemble représente un effectif national moyen de l'ordre de 427 300 individus/an. Parmi ces espèces, dont certaines sont partiellement inféodées à l'eau, 18 dominent avec une valeur cumulée voisine de 90 %. En se basant sur l'indice d'occurrence calculé pour chaque espèce, le peuplement se répartit en 3 espèces communes, 18 espèces fréquentes et 85 espèces rares. Les résultats montrent que les zones humides prospectées sont d'une grande importance internationale pour l'accueil et la conservation des oiseaux d'eau hivernant dans le Paléarctique occidental. L'utilisation des critères de la Convention Ramsar a permis d'identifier un total de 20 sites tunisiens, dont 9 zones humides artificielles, qui répondent au moins à un seul critère. L'application du test global d'ANOVA Kurskal-Wallis aux séries de données relatives à la richesse spécifique, l'abondance moyenne et aux valeurs des diversités de Hill (N 1 et N2), révèle des différences hautement significatives entre les 8 classes de zones humides. Toutefois, l'organisation spatiale des oiseaux aquatiques ne suit aucun gradient précis. En se basant sur le test ANOSYM on discrimine deux grandes associations à savoir les milieux artificiels et les milieux naturels. Ces derniers s'organisent eux-mêmes en 3 sous-associations selon la permanence de l'eau et l'influence des conditions marines. Quant à l'analyse SIMPER, elle distingue une liste de 15 espèces indicatrices des différentes classes de zones humides tunisiennes, aussi bien de type mixte que de type exclusif. L'ensemble de ces espèces indicatrices sont à prendre en considération dans les suivis ultérieurs des zones humides tunisiennes

Ecological diagnosis of the Ichkeul National Park (Tunisia) after dams building : the case of waterbirds

The Ichkeul National Park (INP) has been ratified as a National Park (1980), a Biosphere Reserve under UNESCO’s Man and the Biosphere Program (1977), and a Wetland of International Importance under the Ramsar Convention (1980), and subsequently has been inscribed on the World Heritage List (1980). However, this area is actually threatened by three dams which can retain up to 75 % of the inflow freshwater. According to this situation, fundamental modifications of different components of the INP were recognized. The modification of the hydrological parameters and the response of waterbird community to dam building have been specifically assessed in the present paper. Across 2001–2004, the salinity of the lake ranged from an average of 21 g l−1 in winter to 37 g l−1 in summer with an annual average of 27 g l−1. This latest value was more than two times that recorded before the dams were built. Thus, the densities of Potamogeton and Scirpus populations were dramatically decreased, reducing the available food of herbivorous waterbirds, notably ducks and coots. They were restricted each year to within the mouths of rivers and covered a small area in September before disappearing by the end of October and November. Concerning waterbird communities, a total of 71 species were counted. The commonest species that accounted for more than 54 % of the total abundance of the waterbird communities were : Common Coot (21 %), Common Pochard (16 %), Eurasian Wigeon (12 %) and Greater Flamingo (5 %). The most abundant trophic groups were herbivores (11 species and 75 % of the total abundance of waterbird communities), filterers (3 species and 5 %), vertebrate consumers (14 species and 3 %) and insectivores (26 species and 9 %). Subordinate ones were invertebrates-vertebrates consumers (8 species and 1 %), invertebratesherbivores (6 species and 5 %) and omnivores (3 species and 2 %). The total species richness varied significantly among months. It ranged from 39 to 41 species, between November and December, and the minimum from 12 to 14 species, during June and July. Species abundance also varied significantly between months with a peak during November and December of about 50 000 individuals. The lowest species abundance values were recorded in July and August with an abundance of about 1500 to 3000 individuals. The INP constitutes a very important area during the autumn migration and wintering periods and provides a habitat for a large range of groups of wintering waterbirds, notably herbivorous species. Thus, the competition for resources may be higher in winter than in summer. The total number of species is still decreasing from 93 species (1966-1985) and 90 species (1982-1994) to 71 species in 2001-2004. This variation is most likely dependent on the variation of the number of sporadic species visiting the site than due to the local conditions. The annual density of all waterbird communities decreased dramatically of about 40 % after the building of dams. This condition was mainly caused by the decreasing number of herbivores. Indeed, they presented the lowest peak abundance estimations obtained since the beginning of waterbird counts in the park. There were about 120 000 birds in 1963-1983, 90 000 birds in 1984-1992, 121 000 birds in 1993-1994, but 60 000 in the present assessment. We support the hypothesis that freshwater diversion and increasing salinity caused severe depletion of Potamogeton and Scirpus, and therefore, a worrying reality of the feeding condition for this trophic group. Furthermore, the intensive pressure of feeding exercised by the herbivorous species on wetland production has been identified as having a negative local effect on the Potamogeton population dynamics mainly when the productivity of the Ichkeul National Park was low. From those results, it is suggested that dams built upstream of the Ichkeul National Park caused significant changes to the abundance of waterbird communityDans le Parc National Ichkeul (PNI), entre septembre 2001 et août 2004, les résultats révèlent une richesse spécifique de 71 espèces et une densité annuelle moyenne de 8490 oiseaux/jour/an. Une concentration hivernale des oiseaux d'eau, notamment des herbivores, a été également notée. Bien que l'Ichkeul ait gardé ses potentialités de milieu important pour l'estivage des oiseaux à régime mixte, il se montre en régression pour ce qui concerne les espèces hivernantes-herbivores, de passage-herbivores et nidificatrices. En effet, la construction de trois barrages, les conditions climatiques contraignantes, la mauvaise gestion de l'écluse Tinja et le développement des terres agricoles au détriment des milieux naturels ont entraîné un doublement de la salinité, une diminution de la hauteur d'eau, une exondation des marais et une diminution de la productivité végétative (potamogéton et scirpe). Dès lors, nous avons constaté que la densité annuelle du peuplement des oiseaux a chuté d'environ 40 % en comparaison avec les données antérieures. Cette diminution concerne particulièrement les populations hivernantes et de passage avec des coefficients de variation de la densité respectifs de - 54,88 % et - 22,37 %. En revanche, le nombre total d'espèces fréquentant le PNI s'avère stable et les variations annuelles sont dues aux espèces sporadiques dont la présence ou l'absence sont probablement liées à des facteurs exogènes. En conclusion, des propositions d'aménagement concernant la lagune et les marais sont proposées pour la conservation de ce patrimoine

Comparative Study of Different Active Control Systems of High Rise Buildings under Seismic Excitation

Large number of active vibration control systems existing in the literature has brought lot of confusion for engineers and junior researchers. This study deals with the comparison of different active control systems of a 20-storey building under seismic excitation for three control devices: Active Mass Damper (AMD), Active Bracing System (ABS) and Connected Building Control (CBC). Two different control configurations are considered to add active damping to the building. The first one employs force actuator and displacement sensor and is examined with first and second order Positive Position Feedback, Lead compensators and Direct Velocity Feedback. The second configuration employs a displacement actuator collocated with a force sensor and an Integral Force Feedback control law. A total number of 15 control cases are compared from the point of view of stability, robustness, performance and control effort

On the reputation of communities of web services

Web services communities are virtual clusters that agglomerate Web services with the same functionality. However, selecting the best community to deal with is challenging to both users and providers. Reputation has been widely used for evaluating and ranking candidates. In this paper, we introduce a reputation-based Web services community architecture and define some of the performance metrics that are needed to assess the reputation of a Web service community as perceived by the users and providers. Copyright 2008 ACM

Reuse of Sludge as Organic Soil Amendment: Insights into the Current Situation and Potential Challenges

Sludge generation as an organic by-product of wastewater treatment has seen a consistent increase worldwide due to population growth and industrial activities. This poses a chronic challenge regarding management options and environmental concerns. The agricultural valorization of unconventional organic materials has become inevitable, especially in semi-arid and arid countries that suffer from depleted soils and shortages in farm manure supply. High-income countries have also been interested in this recycling practice to mitigate landfilling or incineration issues. Sewage and some industrial sludges contain a complex mixture of beneficial and harmful substances, which varies with the origin of effluents. Therefore, sludge land application should be well managed in order to achieve sustainable agro-environmental goals. This review paper focuses on different aspects related to sludge reuse in agriculture, starting by investigating the diversity of sludge types and composition. In addition to the preponderant urban sewage sludge, the less-studied industrial sludges, such as those generated from pulp and paper mills or gas-to-liquid industries, are hereby addressed as well. Then, post-land application effects are discussed in relation to sludge quality, dose, and reuse conditions. The present paper also examines the disparities between guidelines that determine sludge conformity for land application in various countries or regions. Accordingly, special attention is given to increasing risks related to emerging pollutants in sludge such as pharmaceuticals, which have been overused since the outbreak of COVID-19 pandemic. This exhaustive investigation will assist the establishment of sustainable strategies for the safe agricultural reuse of biosolids.This review paper is an outcome of the research project M-QJRC-2020-9 funded in the framework of collaboration between Qatar University and Marubeni Corporation.Scopu

Effects of playing surface on physical, physiological and perceptual responses to a repeated sprint ability test: natural grass versus artificial turf

Purpose: The effect of playing surface on physical performance during a repeated sprint ability (RSA) test, and the mechanisms for any potential playing-surface-dependent effects on RSA performance, is equivocal. The purpose of this study was to investigate the effect of natural grass (NG) and artificial turf (AT) on physical performance, ratings of perceived exertion (RPE), feeling scale (FS) and blood biomarkers related to anaerobic contribution [lactate (Lac)], muscle damage [creatine kinase (CK) and lactate dehydrogenase (LDH)], inflammation [c-reactive protein (CRP)] and immune function [neutrophils (NEU), lymphocytes (LYM) and monocytes (MON)] in response to a RSA test. Methods: Nine male professional football players from the same regional team completed two sessions of RSA testing (6 × 30 s interspersed by 35 s recovery) on NG and AT in a randomized order. During the RSA test, total (sum of distances) and peak (highest distance covered in a single repetition) distance covered were determined using a measuring tape and the decrement in sprinting performance from the first to the last repetition was calculated. Before and after the RSA test, RPE, FS, and blood [Lac], [CK], [LDH], [CRP], [NEU], [LYM] and [MON] were recorded in both NG and AT conditions. Results: Although physical performance declined during the RSA blocks on both surfaces (p=0.001), the distance covered declined more on NG (15%) compared to AT [11%; p=0.04, ES=-0.34, 95% CI (-1.21, 0.56)] with a higher total distance covered (+6 ± 2%) on AT [p=0.018, ES=1.15, 95% CI (0.16, 2.04)]. In addition, lower RPE [p=0.04, ES=-0.49, 95% CI (-1.36, 0.42)] and blood [Lac], [NEU] and [LYM] [p=0.03; ES=-0.80, 95% CI (-1.67, 0.14); ES=-0.16, 95% CI (-1.03, 0.72) and ES=-0.94, 95% CI (-1.82, 0.02), respectively)] and more positive feelings [p=0.02, ES=0.81, 95%CI (-0.13, 1.69)] were observed following the RSA test performed on AT compared to NG. No differences were observed in the remaining physical and blood markers. Conclusion: These findings suggest that RSA performance is enhanced on AT compared to NG. This effect was accompanied by lower fatigue perception and blood [Lac], [NEU] and [LYM], and a more pleasurable feeling. These observations might have implications for physical performance in intermittent team sports athletes who train and compete on different playing surfaces

Systematic review of a RAMSAR wetland and UNESCO biosphere reserve in a climate change hotspot (Ichkeul Lake, Tunisia)

Tunisia\u27s Ichkeul Lake is among the most productive ecosystems in the Mediterranean, with a great regional value thanks to its diversity of habitats. It is an important overwintering area for waterfowl species. It is a RAMSAR wetland, a National Park, a UNESCO World Heritage, and a Biosphere Reserve. This review paper provides a broad overview of the climatic, hydraulic, biogeochemical features, bio-resources, and bio-productivity of the Lake. The interconnectivity between the different environmental components of the lake is presented, highlighting the main characteristics of this vital ecosystem. Its ecosystem consists of a permanent lake bordered by temporary marshes. It is connected to the Mediterranean Sea via Bizerte Lagoon under a typical semi-arid to sub-humid bio-climate with wet and dry seasons. The winter rainfall fills up the rivers and lake with freshwater that overflows into the Tinja River. In summer, high evaporation reduces the water level and allows seawater to enter the wetland from Bizerte Lagoon. The ecosystem is threatened by pollution, the damming of its main rivers, and climate change. The unsustainable water management has resulted in fundamental environmental modifications, as evidenced by the large variation in the salinity, water level, productivity of water plants, and the decline in venue and stop-overs of waterbirds. The current situation is a warning that indicates a general perturbation of the resources of this particular site and of Tunisian wetlands in general, especially that the Mediterranean region has been designated as a climate change hotspot. Accurate hydrological management is needed to boost the physical functioning of the ecosystem, and to gain deeper knowledge of the different phases of the water cycle and its relationship to other long-term environmental cycles for sustainable water management strategies in the most water-scarce region in the world

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020