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1.
Environ Monit Assess ; 190(12): 699, 2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30402727

RESUMO

Assessment of the effectiveness of nature conservation measures is a crucial step to ensure that the actions undertaken have achieved the expected results. Depending on the results of such evaluations, managers may need to reframe or even change their approaches. In this analysis, the effectiveness of establishing strictly protected areas was assessed in three important Moroccan Atlantic sites, namely Ad-Dakhla bay, Khnifiss lagoon, and Souss estuary. In particular, we investigated whether protection of these sites was followed by significant changes in the direction and/or strength of change in waterbird species richness and density over time. Our results showed that during the pre-protection period, waterbird species richness has been declining over time, while total waterbird density and the diversity of wading and open-water birds had been maintained at low levels. However, shortly after site protection, a rapid increase in these measures was observed, while there was no significant change in waterfowl species richness and density. Overall, these results suggest that the protection of these wetlands has been a watershed in the recent history of their birds, reversing the trends of a continuing decline towards rapid regeneration. This is one obvious signs of the success of the programme undertaken by the Moroccan authorities to conserve the biodiversity of these wetlands. Further investigations of the effects of protection at all wetlands throughout Morocco are needed to more profoundly understand the role of such conservation measures on shaping wintering waterbird communities.


Assuntos
Biodiversidade , Aves/classificação , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Animais , Marrocos , Estações do Ano , Áreas Alagadas
2.
Animals (Basel) ; 14(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38731356

RESUMO

Moroccan wetlands host up to half a million wintering birds and provide a stopover for tens of thousands of migrants, while they are inhabited by few nesting species. Most of this avifauna prefers to use the large coastal wetlands or reservoirs, while many species are dispersed across hundreds of small inland wetlands of various types. In this study, we monitored the wintering avifauna of 11 wetlands of the Saïss plain and its adjacent Atlas Mountains (north-center of Morocco), during six wintering seasons (2017-2018 to 2022-2023), with the objective of assessing the importance of this region as a waterbird wintering area. Using the richness of the species, we determine the bird population changes during this pentad and between the different types of wetlands (natural, human-made, and natural wetlands). During this study, we recorded 51 species, belonging to 17 families, among which exist four remarkable birds: the endangered Oxyura leucocephala, the vulnerable Aythya ferina and the near-threatened Aythya nyroca and Limosa limosa. Bird diversity is higher in human-made ecosystems than in peri-urban and natural ecosystems, while the populations' size is similar in urban and non-urban wetlands. With regard to bird conservation, these inland wetlands, mainly the small ones, are threatened by recurrent droughts and various anthropic stressors, which we describe using our observations of the two last decades (2003-2023). The loss of habitat is significant, reaching 348.5 hectares, while the impacts of reduced precipitation and temperature increase are particularly evident in the mountainous natural lakes.

3.
Animals (Basel) ; 13(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36830494

RESUMO

The intestinal microbiota of migratory birds participate in the life activities of the host and are affected by external environmental factors. The difference in habitat environment provides diversity in external environmental selection pressure for the same overwintering waterfowl, which may be reflected in their intestinal microbiota. Caizi lake and Shengjin Lake in the Middle and Lower Yangtze River Floodplain are the main habitats for migratory waterfowl in winter, especially the Anser fabalis (A. fabalis). It is important to explore the changes in intestinal microbiota composition and function of A. fabalis in the early overwintering period to clarify the effect of habitat size and protection status on intestinal microbiota. In this study, the composition and structural characteristics of the intestinal microbiota of A. fabalis in Shengjin Lake (SL) and Caizi Lake (CL) were preliminarily explored in order to obtain data for the migratory birds. In both SL and CL groups, 16S rRNA amplicon sequencing analysis showed that Firmicutes was the dominant bacterial phylum, but the relative abundance showed significant differences. Lactobacillus was the most abundant genus in both SL and CL groups. At the species level, the abundance of L. aviaries was the highest, with a relative abundance in both SL and CL groups of more than 34%. When comparing the average relative abundance of the 15 most abundant genera, it was found that Subdoligranulum, Exiguobacterium, and Terrisporobacter had higher abundances in the intestinal microbiota of CL A. fabalis, while Streptococcus and Rothia had higher abundances in the intestinal microbiota of SL A. fabalis. There was only a positive correlation between Bacteroidota and Proteobacteria in the intestinal microbiota flora of SL A. fabalis, and the species were closely related. At the same time, there were positive and negative correlations between Firmicutes and Actinomycetes. However, CL is mainly associated with a positive correlation between Firmicutes and Actinomycetes, and there are also a small number of connections between Firmicutes. PICRUSt1 prediction analysis revealed that the Clusters of Orthologous Groups (COG) functions of SL and CL involve energy production and transformation, amino acid transport and metabolism, carbohydrate transport and metabolism, and transcription. Understanding the changes in intestinal microbiota in Aves during the overwintering period is of great importance to explore the adaptation mechanism of migratory Aves to the overwintering environment. This work provides basic data for an A. fabalis intestinal microbiota study.

4.
Animals (Basel) ; 11(5)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068189

RESUMO

Intestinal microbes participate in life activities of the host, and are affected by external environmental factors. Different habitat sizes and protection status provide different external environmental selection pressures for the same wintering waterbirds, which may be reflected in their intestinal microbes. Hooded Cranes are vulnerable migratory waterbirds with similar numbers wintering at three different lakes in the middle and lower Yangtze River floodplain, Poyang, Caizi, and Shengjin Lakes. Here, we analyzed the characteristics of intestinal bacterial and fungal communities of Hooded Cranes wintering at the three lakes to clarify the effect of habitat size and protection status on intestinal microbes, using high-throughput sequencing technology. Our results showed that community composition and diversity of intestinal microbes were significantly different among lakes with different habitat size and protection status. The Hooded Cranes at Shengjin Lake (small) had higher intestinal microbial alpha-diversity (for both bacteria and fungi) than those at Poyang Lake (large), which might be induced by social behavior of more waterbirds per unit area. The Hooded Cranes at Caizi Lake (relatively poorly protected habitat) had more diverse and abundant intestinal potential pathogens than Shengjin Lake (well-protected habitat). Our results indicated that the environmental pressure of a habitat might affect intestinal microorganisms and more attention might be needed for the vulnerable waterbirds at the habitat of poor protection status.

5.
Integr Zool ; 15(6): 595-602, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32627933

RESUMO

Waterbird diversity is one of the most important indicators for monitoring wetland quality. However, the increasing intensity of reclamation activities in recent decades caused the change of habitat landscape along coasts, which could affect the diversity of wintering waterbirds. Our study tried to investigate how reclamation history and post-reclamation habitats influence the species richness, species abundance, and Shannon-Wiener diversity of wintering waterbirds along Yancheng coastal wetlands. A total of 68 waterbird species were recorded and the abundance pattern of wintering birds changed from 2009 to 2013. Species richness and abundance of wintering waterbirds varied in the different reclamation histories. Most importantly, the general linear mixed model highlighted the importance of reclamation history, post-reclamation habitat type, and their interactions for shaping both species abundance and Shannon-Wiener diversity of wintering waterbirds, but these variables did not affect the species richness of waterbirds. Furthermore, the random forest results also showed a positive association between reclamation history with species richness, species abundance, and Shannon-Wiener diversity of wintering waterbirds. Moreover, three post-reclamation habitat types, Suaeda glauca, bare flat, and fish pond, played important roles for wintering birds. Our results highlighted that reclamation history, post-reclamation habitats, and their interactions determined waterbird diversity. Given the growing threats to wetland ecosystems from reclamation activities, further research should find a balance between coastal reclamation and waterbird biodiversity conservation.


Assuntos
Biodiversidade , Aves , Conservação dos Recursos Naturais , Áreas Alagadas , Animais , China , Ecossistema , Dinâmica Populacional , Estações do Ano
6.
Sci Total Environ ; 655: 147-157, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30469060

RESUMO

Dongting Lake is the second largest freshwater lake in China and is one of the globally important wintering sites for migratory waterbirds in the East Asian-Australasian Flyway. Crucial sites and environmental variables for wintering migratory waterbirds are of great concern in the Dongting Lake wetlands. In this research, based on annual (2003/2004-2016/2017) waterbird and habitat census data, we recognized the crucial sites for waterbirds during wintering seasons by comparing the difference of waterbird populations at the community, foraging guild and species levels in different natural wetlands within East Dongting Lake, and then identified the crucial environmental variables affecting waterbird distributions by analyzing the relationship between waterbird populations and the environmental variables, including vegetation area, mudflat area, water area with the depth of 0-20 cm, water area with the depth of 20-50 cm, water area with the depth of 50-100 cm, water area with the depth >100 cm, growth status of vegetation (Min, Mean and Max NDVI), and the human disturbance. Results indicated that five natural wetlands, i.e., Daxiaoxi, Chunfeng, Baihu lakes, Dingzi dyke and Tanjiaweizi, were recognized as the crucial wintering sites for migratory waterbirds in the East Dongting Lake. Among the ten selected environmental variables, water areas with the depth of 0-20 cm, 20-50 cm and >100 cm, human disturbance, Min and Mean NDVIs were identified as the crucial environmental variables overall. Waterbirds at different levels exhibited significant linear relationship with certain environmental variables, with the exception of Bean goose and Lesser White-fronted goose at the species level, which showed Gaussian distribution with changes in mean NDVI. The crucial environmental variables appeared to be foraging guild- and species-specific. These findings provide significant information for managers to understand the differences of wetlands and waterbird populations within East Dongting Lake, and to make more targeted conservation efforts.


Assuntos
Conservação dos Recursos Naturais , Gansos/crescimento & desenvolvimento , Lagos , Áreas Alagadas , Animais , China , Ecossistema , Gansos/classificação , Sistemas de Informação Geográfica , Dinâmica Populacional , Tecnologia de Sensoriamento Remoto , Estações do Ano
7.
Sci Total Environ ; 573: 645-660, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27592464

RESUMO

An alteration in the hydrological connectivity reduces the synergistic processes and interactions between rivers and their floodplains, and changes the distribution of waterbirds that rely on floodplains as foraging grounds. Recent river and wetland conservation and restoration efforts have been partially focused on reinstating the natural river-floodplain connectivity to ameliorate the ecological effects of regulation in river systems. However, in regions where human well-being is tightly linked with the cultivation of the floodplain (such as fisheries), management options are constrained and trade-offs among competing social, economic and ecological goals may be necessary for the wise use of wetlands. Poyang Lake in east central China includes numerous sub-lakes with different types of hydrological regulation; therefore, this lake may provide a useful context for exploring the likelihood of such trade-offs. In this study, we used multiyear simultaneous waterbird survey data together with habitat maps derived from satellite imagery for Poyang Lake to examine the variations in waterbird community structure and abundance within sub-lakes with different types of hydrological regulation. Using a Bayesian Markov chain Monte Carlo approach, we built generalized linear mixed models to explore the differences in wetland composition and waterbird abundance/diversity among three lake types (i.e. isolated, freely connected, and controlled) at community, guild and species levels. The results showed hydrological connectivity alteration clearly affects wintering waterbirds; in addition, the ecological benefits of a natural flow regime were most unambiguous at the community level. Nevertheless, little evidence exists to indicate that the lakes' ecological values as waterbird foraging grounds were compromised by partial regulation. That is, species richness and population size were comparable in naturally connected and controlled lakes. Our results suggest that, with carefully designed management plans, a delicate balance between waterbird conservation and development can be accomplished in large river floodplains.


Assuntos
Aves/fisiologia , Conservação dos Recursos Naturais , Áreas Alagadas , Animais , Teorema de Bayes , Biota , China , Hidrologia , Lagos , Modelos Lineares , Cadeias de Markov , Método de Monte Carlo , Densidade Demográfica , Estações do Ano
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