, El Harche H, El Hassouni S, Fadli M. 2023. Spatial, seasonal variation and impacts of anthropogenic factors on insect assemblages (Arthropoda: Insecta) in Northwest Morocco. Biodiversitas 24: ...5368-5375. Agriculture has been identified as one of the main causes of biodiversity loss due to the vast area dedicated to this activity. In Morocco, agroecosystems are becoming increasingly developed, which makes it necessary to study their impact on the local entomofauna. We studied the influence of seasonality and anthropogenic activities, including habitat type, on insect diversity in northwestern Morocco. The insects were collected between March 2019 and February 2020, covering all seasons, using three sampling techniques (sweep nets, pitfall traps, and sight hunting). Our study revealed the presence of 83 species, which were classified into 7 orders belonging to 32 families. Our findings demonstrate that insects diversity changes with the seasons, being higher in spring and summer than in autumn and winter. In addition, insect richness varies according to habitat type, with heterogeneous fields showing greater diversity than homogeneous ones. Research also indicates that anthropogenic pressures have had a detrimental impact on insect diversity, particularly in agricultural activities such as grazing, tillage, and the widespread use of pesticides. The results of this study are essential for the effective conservation and management of insect species worldwide. Accordingly, we make several recommendations to help preserve insect diversity and improve their survival, including reducing the massive use of pesticides and contributing to the global effort to reduce the impacts of climate change, which will not be possible without the cooperation of landowners, farmers, managers, and researchers. Therefore, we can enhance effective conservation and ensure insect species' long-term survival by fostering collaboration and knowledge-sharing among these groups.
•Seed production and availability affect plant regeneration.•Habitat structure and composition affect oak acorn phenology, production, and availability.•Lower tree densities promote higher overall ...volume of acorns due to less intraspecific competition.•Infested acorns are more prevalent in habitats with less plant diversity and understory cover.•Habitat type is an important factor affecting primary production and should be considered in future studies.
Seed production and survival are critical steps in the life cycle of plants, and could become bottlenecks for plant regeneration in case of failure. During regeneration many factors, both abiotic and biotic, intervene and interact with each other. After dispersal, environmental variation affects the success of the plant population, so seedling recruitment can display spatial variability. However, few studies of seed production and availability cover a range of habitat conditions (e.g. mature, transitional and post-fire habitats), which makes it difficult to evaluate the potential of site-production relationships. We study how the heterogeneity of habitat structure and composition affects the phenology, production and availability of acorns, mainly holm oak, in a Mediterranean Natural Park. Our results show that meteorological variables determine the phenology of acorn fall. Habitat types present temporal mismatches in falls since, for example, shrublands required a longer period of time for all seeds to fall. Furthermore, habitats with greater tree density and low understory complexity had higher production but smaller acorns. Lower densities promote higher acorn volume (seedling size) as a consequence of less intraspecific competition and more reserves for germination. The proportion of viable acorns available on the ground also decreased substantially in winter, when the proportion of infested acorns increase because the selective consumption of sound acorns by predators. Acorns from mixed forests and shrublands had less pre-dispersal predation by arthropods and post-dispersal predation by wild boar as a result of oak isolation and understory complexity. Conversely, rodents are more abundant in shrublands, where they find a greater diversity of anti-predator refuges and large nutritious acorns available in autumn and winter. Understanding the reproductive constraints imposed by time and space allows us to infer the consequences of environmental changes on population recruitment and persistence. We thus show that habitats with a high density of oak trees, less plant diversity and understory cover had a greater prevalence of infested acorns, thereby reducing recruitment viability. These habitats also had more available acorns on the ground for seed predators. Therefore, habitat type is an important factor affecting acorn production and should be taken into account in future studies.
This manuscript summarizes the outcomes of the 6th EuroSpeleo Protection Symposium. Special emphasis was laid on presenting and discussing monitoring activities under the umbrella of the Habitats ...Directive (EU Council Directive 92/43/EEC) for habitat type 8310 "Caves not open to the public" and the Emerald Network. The discussions revealed a high level of variation in the currently conducted underground monitoring activities: there is no uniform definition of what kind of underground environments the "cave" habitat should cover, how often a specific cave has to be monitored, and what parameters should be measured to evaluate the conservation status. The variation in spatial dimensions in national definitions of caves further affects the number of catalogued caves in a country and the number of caves to be monitored. Not always participants are aware of the complete national monitoring process and that data sets should be freely available or easily accessible. The discussions further showed an inherent dilemma between an anticipated uniform monitoring approach with a coherent assessment methodology and, on the contrary, the uniqueness of caves and subterranean biota to be assessed – combined with profound knowledge gaps and a lack of resources. Nevertheless, some good practices for future cave monitoring activities have been identified by the participants: (1) Cave monitoring should focus on bio- and geodiversity elements alike; (2) Local communities should be involved, and formal agreements envisaged; (3) Caves must be understood as windows into the subterranean realm; (4) Touristic caves should not be excluded ad-hoc from regular monitoring; (5) New digital tools and open FAIR data infrastructures should be implemented; (6) Cave biomonitoring should focus on a large(r) biological diversity; and (7) DNA-based tools should be integrated. Finally, the importance of the 'forgotten' Recommendation No. 36 from the Bern Convention as a guiding legal European document was highlighted.
•Flower fields can have similarly positive effects on bat activity as hedgerows.•AES can promote bats in agricultural landscapes and may provide suitable foraging habitats for bats in homogenous ...landscapes.•Critically endangered bat species were found flying above all our AES.
Agri-environment schemes (AES) have become important tools for farmland biodiversity conservation, providing suitable habitats, resources, and connectivity within the agricultural landscapes. Bats are rarely studied in relation to AES effectiveness in contrast to birds, even though their presence and activity as biological control agents on insects, especially pest species, can be important for agricultural crops. While the role of hedgerows for bat occurrence and activity, as well as for their prey's diversity and abundance has been widely studied, the role of other AESs such as flower fields remains unclear. We monitored the activity of the main functional groups (edge, narrow and open space foragers) using ultrasound recorders, as well as potential prey abundances using light traps, across 35 study sites representing different AES in Central Germany from late July to September 2018. The sampled AES consisted of annual flower fields, mixed flower fields (with annual and biennial vegetation), perennial flower fields (sown every 5 years), hedgerows (surrounded by meadows and agricultural fields), and were compared to winter wheat (control) in a balanced design. Bat activity over hedgerows increased threefold for edge space foragers and sevenfold for narrow space foragers compared to wheat fields. Compared to wheat fields, narrow space forager activity increased fourfold over perennial flower fields, threefold over annual and twofold over mixed flower fields. This group's activity over hedgerows also increased almost threefold compared to mixed flower fields. However, the number of feeding buzzes and prey abundance did not differ significantly between AES. We detected foraging group-specific differences in bat activity between the studied AES. Thus, to promote bats in agricultural landscapes and to ensure their biological control services, it is important to establish more AES, such as hedgerows and flower fields, to increase their diversity and connectivity in intensively used agricultural landscapes.
Lantang B, Najamuddin, Nelwan AFP, Samawi MF. 2023. Density distribution of Penaeus merguensis De Man, 1888 based on habitat in the waters of Merauke District, South Papua Province, Indonesia. ...Biodiversitas 24: 4427-4437. The waters of Merauke District, located in the Arafura Sea area, have relatively hight penaeid resource, but prawn fishing productivity is the lowest of 11th other Indonesian fisheries management areas.. The optimization of the fishery resource utilization remains poor after the moratorium on fishing vessel licensing in 2014, which is only 11%. Hence, a study is needed to determine the resources’ distribution, abundance, and sustainability. This research aims to analyze the density distribution of banana prawn (Penaeus merguensis De Man, 1888) based on the habitat type, each location separated by ~4-5 kilometers within the coastal ecosystem waters of Merauke District. The research was carried out from March to August 2022. Data were collected within each habitat: the catch, prawn fishing equipment, and oceanographic parameters, and then analyses were undertaken using statistical tests. The results showed that the highest density of banana prawn was obtained in shallow waters adjacent to the mangrove habitat at Bokem (32.68 kg/km2) and Yobar (20.27 kg/km2). In waters adjacent to the sandy beach at Payum (17.98 kg/km2), the density was higher than within the estuarine habitat of Maro River (14.60 kg/km2) and adjacent to the sandy beach at Lampu Satu (14.39 kg/km2). This is due to the influx of fresh water in estuarial habitat, sandy beaches in Lampu Satu and Payum, and mangroves in Yobar, resulting in prawn emigration to areas with higher salinity in Bokem mangroves. It is also thought to be associated with increasing turbidity with a similar pattern in salinity and affecting the density of banana prawns.
•Response of functional diversity to wind disturbance depends on forest type.•Functional richness increases after wind disturbance in mixed-coniferous forests.•Species richness increases along with ...wind disturbance.•SLA increases along with wind disturbance, while share of stress-tolerant decreases.
Catastrophic wind disturbance affects not only forest structure and regeneration, but also functional and compositional dynamics of the herbaceous layer. However, the issue of changes in functional diversity and functional trait values of the understory layer in response to wind disturbance has not been addressed so far. This study aims at investigating the patterns of variations in functional diversity, trait values and species richness of herbaceous species following wind disturbance.
The study was carried out in the Piska Forest, a woodland complex in northern Poland, which was almost completely destroyed by a windstorm in 2002 and part of which was successively set aside to study the effects of natural disturbance on forest ecosystems. Vegetation surveys were conducted at 112 sample plots between 2014 and 2015. Four forest habitat types were identified and individually examined. The degree of disturbance severity was assessed as percentage of dead trees on all trees per surface unit. A set of twelve functional traits was assigned to the recorded species.
Three functional diversity metrics (richness, evenness and divergence) were calculated based on the selected functional traits. We assessed the relationship between each of such metric and disturbance severity for each habitat type. The relationship between species richness and disturbance severity was also determined. We then estimated the relative importance of habitat type and disturbance severity on both functional diversity and species richness. Lastly, we examined the response of functional trait values to both disturbance severity and habitat type.
Our results showed that wind disturbance effects on functional diversity are not univocal and that they strongly depend on habitat type. In fact, while in coniferous stands disturbance determined a decrease of functional divergence and left functional richness unaltered, in mixed-coniferous habitats it enhanced functional richness and did not affect functional divergence. In mixed-deciduous habitats, both functional richness and divergence decreased. In swamp habitats no major changes in functional diversity were observed. Changes in functional evenness were not significant. At the same time, disturbance significantly enhanced species richness in all forest habitats, but the coniferous one. It was not possible to clearly disentangle the relative contribution of disturbance and habitat type, since the two are strictly correlated. Out of the tested functional traits, only SLA, seed releasing height and share of stress-tolerant species exhibited significant response along the tested disturbance gradient. Most of the other traits reacted only to variations in the habitat type.
Increasing nitrogen depositions adversely affect European landscapes, including habitats within the Natura2000 network. Critical loads for nitrogen deposition have been established to quantify the ...loss of habitat quality. When the nitrogen deposition rises above a habitat-specific critical load, the quality of the focal habitat is expected to be negatively influenced. Here, we investigate how the quality of habitat types is affected beyond the critical load. We calculated response curves for 60 terrestrial habitat types in the Netherlands to the estimated nitrogen deposition (EMEP-data). The curves for habitat types are based on the occurrence of their characteristic plant species in North-Western Europe (plot data from the European Vegetation Archive). The estimated response curves were corrected for soil type, mean annual temperature and annual precipitation. Evaluation was carried out by expert judgement, and by comparison with gradient deposition field studies. For 39 habitats the response to nitrogen deposition was judged to be reliable by five experts, while out of the 41 habitat types for which field studies were available, 25 showed a good agreement. Some of the curves showed a steep decline in quality and some a more gradual decline with increasing nitrogen deposition. We compared the response curves with both the empirical and modelled critical loads. For 41 curves, we found a decline already starting below the critical load.
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•Estimating response curves for habitat types for nitrogen deposition.•Nitrogen deposition seems to have a stronger effect than the critical loads indicate.•Many nitrogen deposition sensitive habitat types show a decreasing trend in quality.•Sensitive habitat types show a quality decrease at the lowest nitrogen deposition.
Mosquitoes are a vector of human disease transmitting malaria, and many arboviruses such as dengue virus and Zika virus. This study determined mosquito larval occurrence and abundance in residential ...areas around Suratthani Rajabhat University as influenced by ecological factors and breeding container diversity. Mosquito larvae were collected using a standard dipping method from 95 locations during April through September 2019 and environmental factors such as physicochemical parameters of water in the breeding containers were measured. During the survey, a total of 194 houses were inspected, of which 58 were found to be infested with mosquito larvae, with a house index of 29.90, a container index of 25.55, and a Breteau index of 48.99. A total of 5,123 mosquito larvae were reported from seven breeding habitat types namely, plastics, cement, mud pots, glass, foam, discarded tires and natural materials. Among the collected larvae, Aedes albopictus (56.45%) was most prevalent, while Culex sp. (22.33%) and Aedes aegypti were less prevalent (21.21%). The most common mosquito larvae breeding habitats were plastics (44.22%) followed by discarded tires (18.14%). The spearman correlation analysis showed that the number of mosquito larvae were significantly positively correlated with the depths and width of containers (p<0.05). These findings are helpful in understanding the ecological factors and breeding habitat types that influence mosquito species and their abundance, and also in determining ways to control mosquito borne diseases.