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Sci Rep
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Scientific Reports
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10.1038/s41598-024-72479-9
Article
Ecological networks in savannas reflect different levels of hydric stress in adjacent palm swamp forest ecosystems
http://orcid.org/0000-0003-0157-6151
de Araújo Walter Santos walterbioaraujo@gmail.com

1
http://orcid.org/0000-0002-2428-7435
Silveira Luana Teixeira 2
1 https://ror.org/01hewbk46 grid.412322.4 0000 0004 0384 3767 Department of General Biology, Center for Biological and Health Sciences, State University of Montes Claros, Montes Claros, Brazil
2 https://ror.org/0039d5757 grid.411195.9 0000 0001 2192 5801 Graduate Program in Animal Biodiversity, Institute of Biological Sciences, Federal University of Goiás, Goiânia, 74690-900 Brazil
12 9 2024
12 9 2024
2024
14 2131722 5 2024
9 9 2024
© The Author(s) 2024
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
Palm swamp forests are wetland ecosystems typical of the Brazilian Cerrado, which in recent decades have undergone intense changes due to land use alterations and climate change. As a result of these disturbances, many palm swamps have been experiencing significant drying, which can also affect adjacent vegetation. In the present study, we evaluated whether the drying of palm swamps affects the structure of plant–herbivore networks located in adjacent savanna areas in Brazil. Our results show that savanna areas adjacent to dry zones of palm swamps have fewer interactions, fewer interacting species, and a less specialized topology, which corroborates our expectations. Our findings indicate that the drying of palm swamps also has propagated impacts on adjacent savanna vegetation, impairing more specialized interactions in these environments. On the other hand, contrary to expectations, plant–herbivore networks in dry zones displayed higher modularity, lower nestedness and lower robustness than those in wet zones, suggesting that in dry environments, species tend to compartmentalize their interactions, even with lower interaction specialization. This is the first study to investigate the impacts of environmental drying on the structure of plant–herbivore networks in tropical ecosystems, highlighting the complexity of these effects and their differential impact on specialized and generalized interactions. Understanding these dynamics is crucial for developing effective conservation and management strategies in the face of ongoing environmental changes.

Keywords

Anthropogenic disturbances
Ecological interactions
Nature conservation
Veredas
Wetland drying
Subject terms

Community ecology
Ecological networks
Tropical ecology
http://dx.doi.org/10.13039/501100004901 Fundação de Amparo à Pesquisa do Estado de Minas Gerais APQ-03236-22 de Araújo Walter Santos issue-copyright-statement© Springer Nature Limited 2024
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pmcIntroduction

Anthropogenic interferences are drastically changing the climate and environmental characteristics of many terrestrial ecosystems1. As a reflection of these anthropogenic changes, many typically wet ecosystems are undergoing a drying process, as is the case with the palm swamp forests in the Brazilian Cerrado2. These wet forests are responsible for the recharge and maintenance of groundwater and the supply of surface watercourses3,4. As a consequence of the drying of the palm swamps, many adjacent ecosystems have also experienced a decrease in water availability, such as the fields and savannas that typically surround this vegetation5. Despite recent advances in studies on the drying of palm swamp forests and its effects on plant5 and insect6 communities, further studies are still needed to investigate how this drying may impact interactions between plants and insect herbivores, which are among the most diverse groups in terrestrial ecosystems.

Palm swamp forests are typical hygrophilous forest ecosystems found in the Brazilian Cerrado5. These forests are characterized by the presence of palm trees, particularly the buriti palm (Mauritia flexuosa), which dominates the landscape alongside other species7. In southeastern Brazil, the palm swamp forests are typically associated with areas of permanent watercourses, providing vital habitats for a diverse array of flora and fauna8. Surrounding these palm swamp forests are adjacent vegetation, often consisting of neotropical savannas5. These adjacent ecosystems are influenced by the presence of the palm swamps, with species compositions and interactions influenced by the proximity to water sources and the distinctive microclimatic conditions of the palm swamp forests8. In recent decades, changes in land use, such as the suppression of natural vegetation for pasture and agriculture, which impairs the recharge of the water table, associated with climate alterations leading to a reduction in rainfall, have caused the drying of palm swamps5. It is already known that drying can alter the structure of vegetation and ecological interactions within the palm swamps5,9. However, it is not yet known if these impacts propagate to adjacent vegetation, such as savanna areas, and whether this can affect interactions between plants and herbivorous insects.

Environmental drying and a decrease in soil moisture can carry substantial ecological implications for both plant diversity and plant physiology10. These impacts can be particularly important in savanna vegetation, which tends to experience greater soil water limitation compared to forested areas11. Firstly, a decrease in soil moisture levels is likely to impact plant diversity by favoring species adapted to drier conditions and disadvantaging those that require higher moisture levels for optimal growth12. This shift in species composition can lead to changes in community structure and the loss of specialized plant species reliant on moist environments, potentially reducing overall biodiversity5. Secondly, diminished soil moisture can directly affect plant physiology by limiting water availability for essential processes such as photosynthesis, nutrient uptake, and growth10. Plants may exhibit reduced vigor, altered leaf morphology, and increased susceptibility to environmental stressors such as heat and drought. These physiological changes can influence plant–herbivore interactions by altering the nutritional quality and defensive traits of plants, potentially affecting herbivore performance and behavior13. Additionally, the decrease in soil moisture can lead to changes in plant chemistry, including alterations in secondary metabolites14, which may influence herbivore feeding preferences and plant susceptibility to herbivory. Overall, the diminished soil moisture is expected to have cascading effects on plant diversity, and herbivore interactions, highlighting the importance of understanding and mitigating the impacts of environmental changes on terrestrial ecosystems.

Interactions between plants and herbivorous insects can form complex networks of ecological interactions in tropical ecosystems15. Ecological interaction networks provide a valuable framework for studying the effects of environmental changes on interspecific interactions16. Environmental changes can affect species diversity and interactions within the network, directly impacting the size of the networks, but they can also affect the topology of their interactions17,18. One way to assess the topology of interactions is by evaluating modularity, which is a measure of the occurrence of densely connected subgroups of species within the network18. Plant–herbivore networks with a modular structure indicate that interactions are not homogeneously distributed among species, but there are compartments within the network that can be formed by phylogenetic or ecological constraints on the interactions17. Ecological networks can also be evaluated for their specialization, quantifying the degree of specialization of interactions among different species within the entire network18. In contrast to the topological pattern of high specialization, plant–herbivore networks tend to exhibit low nestedness15, which is a structural pattern where specialized interactions are nested within generalized ones18. Because the topological patterns of networks can influence the robustness of communities to extinction16, studying plant–herbivore networks in the context of palm swamp drying allows for the assessment of how alterations in habitat conditions influence interaction diversity and organization within these networks. By analyzing the responses of plants and herbivores to palm swamp drying, it is possible elucidate the mechanisms driving changes in network structure, such as shifts in species interactions and the loss of specialized plant–herbivore associations. It is expected that specialist species (i.e., species with few specialized interactions) are more sensitive to environmental disturbances than generalist species (i.e., species with generalized interactions)17. Since the loss of species with few connections tends to decrease the specialization of bipartite networks18, this is possible that drying may lead to a decrease in network size, specialization and, modularity and increment in the network nestedness and robustness of plant–herbivore networks.

In the present study, we evaluated the impacts of the drying of palm swamp forest ecosystems on the structure of interaction networks between host plants and free-living herbivorous insects in adjacent savannas. Free-living insects were used because they constitute the most diverse group of herbivores in tropical ecosystems, exhibiting a wide variety of taxonomic groups and feeding guilds15. For this, we collected data on plant–herbivore interactions and constructed ecological networks for different areas located in wet zones of preserved palm swamps, as well as in areas of palm swamps that have undergone drying in recent years (dry zones). The plant–herbivore networks were characterized using different topological descriptors (number of interactions, network size, network specialization, network modularity, network nestedness and network robustness). We hypothesized that the drying of the environment depletes specialized plant–herbivore interactions and promotes the dominance of more generalized interactions. Given this, our prediction is that drying reduces the number of interactions and network size, and decreases the specialization and modularity of the plant–herbivore networks. Furthermore, we also expected that networks in dry zones would have a more nested and robust structure than those in wet zones.

Materials and methods

Study area

The study was conducted in three palm swamp ecosystems located in the Northern region of Minas Gerais state, Brazil (Fig. 1). The first is the Vereda Pedras (14°53′18″ S and 45°20′31″ W), located in the Private Natural Heritage Reserve (PNHR) Porto Cajueiro, in the Cochá e Gibão Environmental Protection Area, Januária municipality. The second is the Vereda Almescla (15°21′37″ S and 44°54′45″ W), located in the Rio Pandeiros Environmental Protection Area, Bonito de Minas municipality. The third is the Vereda Peruaçu (14°56′13″ S and 44°37′44″ W), situated in the Veredas do Peruaçu State Park, spanning Januária and Cônego Marinho municipalities. The studied areas are part of the sampling sites of the Long-Term Ecological Research Project PELD-Veredas. Each palm swamp forest studied encompasses an area of approximately 6 km in length and maintains an altitude ranging from 800 to 900 m above sea level7. The climate in the region is classified as tropical, labeled as Aw according to the Köppen classification19. It features dry winters and an average yearly temperature ranging from 22.2 to 22.7 °C, with annual rainfall varying between 1008 and 1073 mm. The region is located in the Brazilian semi-arid zone, which is one of the areas with the most significant water deficit problems in the country.Fig. 1 Location of the nine sampling areas in the Northern Region of Minas Gerais, Brazil. Blue circles represent wet areas and gray circles represent dry areas. The map was created using ArcGIS, version 10.6.1, (https://www.esri.com/en-us/arcgis/about-arcgis/overview).

Sampling design

In the different palm swamps, we delimited sampling areas spaced 2 km apart in the upstream, midstream, and downstream regions along the length of the palm swamp6. Each of these areas was classified as a wet zone, with the presence of surface water in the palm swamp channel, or a dry zone, without the presence of surface water in the palm swamp channel5,6. This classification was carried out based on annual monitoring of the surface water level in the palm swamp channel, so that dry zones were those that did not present surface water at any time of the year6. We collected plants and insect herbivores in November 2023 (rainy season) took place in areas of neotropical savanna (cerrado sensu stricto) adjacent to the dry and wet zones of the different palm swamps (Fig. 1). The savanna areas were, on average, 100 m away from the palm swamp channel. In each sampling area, five plots of 100 m2 were established. All plants with a circumference of 15 cm or greater were identified at species level in field by botanical specialists and selected for insect sampling. Herbivorous insects were collected from each plant by selecting three branches and performing the beating method with an entomological umbrella (10 beats per branch)20. The collected specimens were stored in appropriately labeled containers with 70% alcohol. Insects were identified to the most precise taxonomic level possible (families or genera) and classified into morphospecies based on their external morphological features20. The determination of herbivores was based on field observations of feeding habits, mouthpart morphology, and the taxon of herbivorous insects20. In the present study, we considered only free-living chewing and sucking herbivorous insects.

Plant–herbivore network descriptors

For each sampling site, we constructed quantitative adjacency matrices with plant species in the rows, insect species in the columns, and insect abundance in the cells. A total of nine networks were constructed, with five for wet zones and four for dry zones. Sampling effort was assessed considering each combination of a plant species and an insect species as a “species”, and the number of insects recorded between pairs in the network as “abundance”21. Interaction diversity was estimated using the Chao1 species richness estimator, and the sampling effort was calculated as the ratio between the observed and estimated richness of interactions22. The Chao 1 estimator was calculated using the INEXT package in the R program23.

We built bipartite interaction networks, which were described using the following topological descriptors: number of interactions (number of links), network size (number of interacting species), network specialization24, network modularity25, network nestedness26 and network robustness27. Specialization in each network was assessed using the H2’ index, which characterizes how herbivores and plants distribute their interactions based on partner availability across the network24. The H2’ index ranges from 0 (no specialization) to 1 (total specialization). Additionally, we also calculated the modularity to quantify the prevalence of interactions within subsets of species using the DIRTLPAwb + algorithm25, ranging from 0 (non-modular) to 1 (perfectly modular). We calculated nestedness using the WNODF (weighted NODF) metric26, which takes values between 0 (perfectly non-nested) and 100 (perfectly nested). Finally, we calculated the robustness of networks to co-extinctions of the second trophic level using the robustness function (ranging from 0—low robustness to 1—high robustness)28. To compare the significance of the values observed in network descriptors (specialization, modularity, nestedness, and robustness), we used 999 null networks generated with the r2d null model28. All network analyses and graphs were constructed using the bipartite package in R software27.

Statistical analyses

We tested if wet and dry zones of the palm swamps differ in the network descriptors (number of interactions, network size, network specialization, network modularity, network nestedness and network robustness), using generalized linear mixed-effects models (GLMMs). In each model, the area (Vereda Pedras, Vereda Almescla and Vereda Peruaçu) was used as a random effect variable to control for potential intrinsic differences between areas that may affect plant–herbivore interaction structure. In the models for network descriptors (specialization, modularity, nestedness and robustness), the network size was included as an additional explanatory variable to control the possible effects of the species richness on the network structure28. Model residuals were checked for distribution, and appropriate error distributions were employed. We used the lme4 package29 to build the GLMMs using the R version 4.2.330.

Results

In total, the networks were composed of 53 host plant species, 97 free-living herbivorous insect species, and 197 distinct interactions (Fig. 2; Table S1). The most representative plant families were Fabaceae, with 12 species, and Vochysiaceae, with six species. The most representative insect groups were the orders Hemiptera, with 45 species, and Coleoptera, with 35 species, as well as the families Cicadellidae (Hemiptera), with 17 species, and Curculionidae (Coleoptera), with 16 species. The most important host species in the wet zones were Lafoensia pacari with 14 insect species and Qualea parviflora with 11 insect species (Table S1). In the dry zones, the most important species were Qualea parviflora and Qualea grandiflora, hosting 12 and nine herbivorous insect species, respectively.Fig. 2 Plant–herbivore networks constructed for wet and dry areas of neotropical savannas adjacent to the palm swamp forests. The upper black bars represent insect herbivore species; the lower black bars represent plant species, and the gray lines indicate interactions between the species. The width of the lines represents the number of interactions (number of insects recoded by plant species).

The networks showed a considerable range in effort percentages (Table S2; Fig. S1), ranging from 45.5 to 100.0% relative to the total estimated interactions. Networks with the highest sampling efforts were network 8 (dry zone) at 100.0%, and network 5 (wet zone) at 87.1%, while networks with the lowest efforts were network 4 (wet zone) at 45.5%, and network 9 (dry zone) at 54.4%, suggesting less intensive sampling relative to their theoretical estimates. Only the network 4 (wet zone) had a sampling effort lower than 50%. The number of interactions within the networks ranged from five to 41 interactions (22.5 ± 10.8), with wet zones showing twice as many interactions as dry zones (29.2 ± 7.5 and 14.2 ± 8.6, respectively) (Table 1; Fig. 3a). Network size ranged from 11 to 43 (29.0 ± 12.1), being larger in wet zones (35.8 ± 8.6) compared to dry zones (20.5 ± 10.6) (Table 1; Fig. 3b).Table 1 Results of the generalized linear mixed-effects models (GLMMs) evaluating the effects of palm swamp zone (dry vs. wet) on the number of interactions, size, specialization, modularity, nestedness and robustness of plant–herbivore networks in adjacent cerrado areas, in the Northern region of Minas Gerais, Brazil.

Response variables	Dry zone	Wet zone	Chisq	P-value	
Number of interactions	14.2 ± 8.6	29.2 ± 7.5	9.988	0.002	
Network size	20.5 ± 10.6	35.8 ± 8.6	7.318	0.007	
Network specialization	0.56 ± 0.26	0.31 ± 0.30	3.879	0.049	
Network modularity	0.75 ± 0.08	0.66 ± 0.09	6.339	0.012	
Network nestedness	0.69 ± 1.39	3.07 ± 3.09	9.350	0.002	
Network robustness	0.48 ± 0.11	0.60 ± 0.007	4.936	0.026	

Fig. 3 Comparison of the number of interactions (a), network size (b), network specialization (c), network modularity (d), network nestedness (e) network robustness (f) between wet and dry areas of neotropical savannas adjacent to palm swamp forests.

Most networks were significantly more specialized and more modular than expected by the null models (Table S3). Network specialization ranged from 0.00 to 0.82 (0.47 ± 0.28), while modularity ranged from 0.54 to 0.85 (0.70 ± 0.09). Network specialization was higher in wet zones (0.56 ± 0.26) than in dry zones (0.31 ± 0.30) (Table 1; Fig. 3c). On the other hand, network modularity was higher in dry zones (0.75 ± 0.08) than in wet zones (0.66 ± 0.09) (Table 1; Fig. 3d). We did not find an effect of network size on specialization (χ2 = 0.237, p = 0.626) or modularity (χ2 = 1.868, p = 0.172).

Network nestedness ranged from 0.00 to 7.92 (2.02 ± 2.66), while robustness ranged from 0.11 to 0.55 (0.71 ± 0.32). Both nestedness (Table 1; Fig. 3e) and robustness (Table 1; Fig. 3f) were higher in the wet zones (3.07 ± 3.09 and 0.60 ± 0.007, respectively) than in the dry zones (0.69 ± 1.39 and 0.48 ± 0.11, respectively). However, most of the networks analyzed did not show a pattern of nestedness or robustness that differed from what would be expected by chance (Table S3).

Discussion

Our results show that the structure of ecological networks of host plants and free-living herbivorous insects in savannas is affected by the level of drying of adjacent palm swamp forests. Corroborating our expectations, the number of interacting species (network size) and the number of interactions between partners were lower in zones that experienced drying compared to wet zones of the palm swamps. Additionally, network specialization in dry zones was also lower than in wet zones, suggesting a decrease in species with specialized interactions in the former. Contrary to our expectations, however, plant–herbivore networks in dry zones exhibited higher modularity, lower nestedness and lower robustness than those in wet zones. These results suggest that in dry environments, even with lower interaction specialization, species tend to compartmentalize their interactions.

The observation that the network size, measured the by number of interacting species, was lower in zones that experienced drying compared to wet zones of the palm swamp forests can be attributed to several ecological factors. In wet zones, the availability of water and nutrients tends to be higher and more consistent31, supporting greater plant diversity32–34, and, consequently, a larger number of herbivorous insects31. In contrast, dry zones tend to have limited resources, reducing plant diversity and the insects they support35. Additionally, drying conditions can increase physiological stress, and alter plant chemical compositions, increasing defensive compounds13 and making them less palatable to insects36,31. This leads to fewer insect species surviving and interacting with plants. Consequently, the number of interactions in communities from dry areas is also lower than in wet zones, which also affects the topology of plant–herbivore networks. As our results indicate that, for some networks, the sampling effort was below the expected threshold (< 70%), it is essential to increase sampling efforts in the palm swamp forests, for example, by sampling interactions multiple times throughout the year to capture seasonal variations in these interactions.

As expected, we found that most of the plant–herbivore networks in palm swamps were significantly specialized, and the level of specialization differed among the environments studied. Many herbivorous insects rely on specific host plants that thrive in moist conditions, so their decline in dry zones decreases interaction complexity. Consistent with our expectations, the wet zones exhibited more specialized networks than the dry zones of the palm swamps. We hypothesized that changes in the microclimatic and ecological characteristics of dry areas may lead to a disproportionate loss of species with more specialized interactions, because specialist and generalist herbivores tend to exhibit different responses to environmental changes that can impact plant physiology13. In this context, generalist free-living species in terms of interactions with plants (i.e. polyphagous) may become more prevalent, making the networks in these environments less specialized37. Our findings are in line with previous studies that have reported a decrease in the number of specialist insects and in the specialization of plant–herbivore networks in response to anthropogenic environmental changes38,39.

Our results show that most of the plant–herbivore networks in palm swamps exhibit a significantly modular pattern, corroborating the expected pattern for plant–herbivore networks18,20. Networks in dry zones exhibited higher levels of modularity than those in wet areas. This result, besides contradicting our initial expectation of more modular networks in wet environments, also goes against the expected pattern of a positive correlation between specialization and modularity of networks40. Thus, our findings show that in the dry zones of the palm swamps, despite the low specialization of the networks, they tend to have more modular interactions. One possible explanation for this result is that in dry environments where resources are limited and patchily distributed, species may exhibit greater niche partitioning to effectively exploit available resources5,6, leading to the formation of distinct modules within the network. Previous results showed that high niche partitioning can promote a highly modular structure in plant–herbivore networks41. High niche partitioning in ecological communities can result from intense interspecific competition and environmental heterogeneity31. Competition drives species to occupy distinct ecological niches, reducing overlap in resource use41. On the other hand, environmental variability, such as in dry zones, supports diverse microhabitats that encourage species to adapt to specific ecological roles31. These factors can collectively foster a modular structure in plant–herbivore networks, where species interact more within specialized modules than across them. Furthermore, differences in species composition and interactions between wet and dry zones may also contribute to variations in network modularity40. Dominant species in dry zones, resilient to environmental stressors, may form the core of modular structures, interacting with a subset of species within their respective modules42. This is the case, for example, of the plant Qualea grandiflora (Vochysiaceae), which occurred exclusively in dry zones. It was one of the most abundant plants and had the highest number of interactions, hosting nine species of herbivorous insects (Table S1). Conversely, in wet zones where resources are more abundant and evenly distributed, species interactions may be more evenly distributed across the network, resulting in lower modularity.

While higher modularity in ecological networks is often associated with increased stability by restricting the propagation of extinctions after a perturbation43, this was not observed in our study. In fact, we found that the dry zones had lower robustness than the wet zones, despite having higher modularity. Our results suggest that network robustness tends to be negatively correlated with modularity and positively affected by nestedness, a pattern already documented in previous studies44. The higher nestedness and robustness in the wet zones compared to the dry zones could be indicative of the more stable and resource-rich environment provided by the presence of surface water. As networks in wet zones had greater species diversity (network size) and interactions, this can create more nested and resilient ecological networks44. This higher robustness suggests that these networks are more resilient to species extinctions, possibly due to the presence of multiple alternative interactions that can compensate for the loss of particular species16. However, these results should be interpreted with caution because most of the networks did not show robustness different from the null models, and all the networks analyzed had low (< 10) and non-significant nestedness values.

The drying of environmental habitats, such as palm swamp forests, can have significant impacts on the conservation of plant–herbivore interactions. As these habitats undergo drying, there is a notable decrease in the availability of water and nutrients, leading to alterations in vegetation structure and composition5. This change directly affects the distribution and abundance of plant species5, subsequently influencing the diversity and abundance of herbivorous insect populations that depend on them7. The reduction in plant diversity may lead to a decline in specialized interactions between plants and herbivores, as certain plant species that are essential for the survival of specific insect species may become less prevalent or disappear entirely45. Additionally, the alterations in microclimatic conditions and resource availability in dried habitats may favor the dominance of generalist species over specialists27, altering the dynamics of plant–herbivore networks. Overall, the drying of environmental habitats poses a significant threat to the conservation of plant–herbivore interactions, highlighting the importance of mitigating habitat degradation and implementing conservation measures to preserve the integrity and functionality of these ecosystems.

In conclusion, our study provides evidence that the drying of palm swamps can affect the structure of plant–herbivore networks in adjacent vegetation, such as the neotropical savannas often found surrounding these humid environments. Consistent with our expectations, wet zones exhibited plant–herbivore networks with more interacting species, a higher number of interactions, and a more specialized structure compared to dry zones. These results support the hypothesis that the drying of palm swamps leads to the loss of species with specialized interactions and the dominance of species with generalist interactions. Surprisingly, however, networks in dry zones were more modular than those in wet areas, contrary to our expectations. This indicates that the impacts of environmental drying can have complex effects on the configuration of plant–insect interactions in natural terrestrial ecosystems. To mitigate these effects of palm swamp drying, the primary measure is the maintenance and restoration of natural vegetation, which aims to maximize the recharge of the water table. Future research should explore the underlying mechanisms driving these patterns and their broader implications for ecosystem resilience and conservation strategies. These studies could be advanced by increasing the number of palm swamps sampled, enhancing the sampling effort for interactions, and including different types of ecological interactions, such as pollination and seed dispersal. Additionally, government incentives for sustainable land use practices, increased funding for ecological research, and community-based conservation initiatives are essential to improve this situation and ensure the long-term health of palm swamp ecosystems.

Supplementary Information

Supplementary Figure S1.

Supplementary Table S1.

Supplementary Table S2.

Supplementary Table S3.

Supplementary Information

The online version contains supplementary material available at 10.1038/s41598-024-72479-9.

Acknowledgements

The authors thank to the colleagues of the Laboratory of Ecological Interactions and Biodiversity—LIEB for their help in field collections, to the Érica Freitas for plant identification, and to the RPPN Porto Cajueiro team for the collection permit and the support in field activities.

Author contributions

Walter Santos de Araújo: Methodology, Calculation, Writing Revising the Original draft, Sample Analysis, Investigation, Revising the Original draft, Validation, Supervision. Luana Teixeira Silveira: Methodology, Calculation, Writing Original draft, Sample Analysis, Revising the Original draft. All authors approved the final manuscript.

Funding

This research was supported by LIEB projects (FAPEMIG APQ-00394-18; APQ-03236-22), and the Long-term Ecological Research Network (PELD-VERE) of the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq 441440/2016-9; 441583/2020-2; 308877/2019-5), Coordenação ao de Aperfeiçoamento de Pessoal de Nível Superior (CAPES 88887.136273/2017–00), and Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG APQ-04816-17; CRAPPM-00539-18; APQ-04816-17).

Data availability

The datasets generated during the current study are available from the corresponding author on reasonable request.

Competing interests

The authors declare no competing interests.

Publisher's note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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