The Kaya forests in Southern Kenya are valuable habitats for rare animal and plant species and provide various ecosystem services. The Kaya forests are also centres of cultural life and are of great relevance to rites, traditions, and the social order of the community of people. During the past decades, these forest remnants become under extreme pressure due to land use and resource exploitation and are in danger of disappearing completely during the next years. This negative trend is progressing with the increasing population density. In addition, the relevance of the former cultural rites is increasingly being forgotten, and with it the relevance of these places. In order to preserve these forest remnants in the long term, it is important to make the population aware of the numerous and valuable ecosystem services, as well as to bring the former cultural life back into the centre of society. A general prerequisite to efficiently conserve Kayas might be the improvement of communication among generations, such as between the elders of Kayas and the youth, as well as among elders from different Kayas to harmonize conservation strategies and the sustainable use of these forest remnants. In addition, strengthening the communication between state institutions and the elders of the individual Kayas might help to find a common strategy to conserve Kaya forests.

Forest succession drives concomitant changes in associated faunal communities. Thus, maintaining landscapes with high successional diversity can be an important consideration in habitat management. We sought to describe avian community characteristics across a successional gradient created by reforestation efforts in a tropical premontane wet forest in Costa Rica. Specifically, we examined the effects of successional stage on overall abundance, species richness, diet niche, migratory status, and community composition. We hypothesised that these metrics of bird abundance, diversity and community composition would differ across successional stages. Using data from transects conducted in 2018, we found that several metrics of avian abundance, diversity and community composition varied as a function of successional stage. Surprisingly, the earliest successional stage exhibited the greatest abundance, species richness and proportion of migrant species. We suggest that an ephemeral vegetation structure present for only a short period (early in succession) creates a unique habitat that results in a distinct avian community. This highlights the potential importance of early successional forests for avian communities, especially neotropical migrants.

A trade-off between structural and chemical defences against herbivory in woody plants is alleged to depend on edaphic factors in African savannas. We studied anti-herbivory traits, in an edaphic mosaic of fertile and infertile soils within a savanna landscape in East Africa, towards elucidating herbivory defence traits expressions in woody plants of African savannas. We used data of 81 plants for 8 species from 8 sites — four sites from fertile soils (42 plants) and another four sites from infertile soils (39 plants). We did not find a general divide between structural and chemical strategies in our data. Instead, we found a range of defence traits combinations. Our results highlight that in woody plants of African savannas, chemical and structural defences can augment each other, and not necessarily trade-off. The diversity of herbivores, ranging from insects to mesobrowsers, may have driven the evolution of multiple defence strategies within the African savannas.

Oil palm is one of Southeast Asia’s most common crops, and its expansion has caused substantial modification of natural habitats and put increasing pressure on biodiversity. Rising global demand for vegetable oil, coupled with oil palm’s high yield per unit area and the versatility of the palm oil product, has driven the expansion of oil palm agriculture in the region. Therefore, it is critical to identify management practices that can support biodiversity in plantations without exacerbating negative impacts on the environment. This study focuses on day-flying Lepidoptera (butterflies and moths), which contribute to the ecosystem functioning as pollinators, prey, and herbivore species. We assessed whether density and behaviours of day-flying Lepidoptera varied between different habitats within oil palm plantations and across seasons. We surveyed the density and behaviours of Lepidoptera communities in mature industrial oil palm plantations within the Biodiversity and Ecosystem Function in Tropical Agriculture (BEFTA) Programme sites, in Riau, Indonesia. We surveyed two distinct habitats within the plantations in March and September 2013: Edge habitats, which were bordered by plantation roads on one side, and Core habitats in the centre of oil palm planting blocks. We conducted analyses on the effect of habitat type and season on both the overall density and behaviour of Lepidoptera communities and, independently, on the most common species. In our surveys, we observed 1464 individuals across 41 species, with a significantly higher density in Edge than in Core habitats. While there was no significant difference between overall density in March and September surveys, there was an interaction between season and habitat, with density increasing more markedly in Edge than Core areas in September. There was also a significant effect of habitat and season on behavioural time budget for the community as a whole, with more active behaviours, such as foraging and mating, being recorded more frequently in Edge than Core habitats, and more commonly in September than March. The effect of habitat type, season, and their interaction differed between the six most common species. Our findings indicate that Lepidoptera abundance is affected by habitat characteristics in a plantation and can therefore be influenced by plantation management practices. In particular, our study highlights the value of road edges and paths in plantations for day-flying Lepidoptera. We suggest that increased non-crop vegetation in these areas, achieved through reduced clearing practices or planting of flowering plants, could foster abundant and active butterfly communities in plantations. These practices could form part of sustainability management recommendations for oil palm, such as those of the Roundtable on Sustainable Palm Oil.

Long-term climate and vegetation data were used to determine the role of rainfall variability and its seasonal distribution on litterfall nutrients. Based on a 20-year data set on rainfall (range 334–1,506 mm per year) and litterfall nutrients from old-growth tropical dry forest (TDF) in Mexico, we examined litterfall N and P concentrations from the rainy and dry seasons in response to rainfall in the rainy (June–October) and the dry (November–May) seasons, the latter referred to as out-of-season precipitation (OSP). Rainy-season litterfall N concentrations, but not P concentrations nor N:P ratios, changed positively (p < 0.001) in response to rainy-season precipitation. Dry-season litterfall N concentrations and N:P ratios, but not litterfall P, increased (p ≤ 0.02) in response to rainfall from the preceding rainy season. N:P ratios of dry-season litterfall in years with OSP were higher only during dry years and N concentrations decreased in wet years (p < 0.05). The narrow range in dry-season litterfall P concentrations (1.00–1.15 mg g-1), irrespective of rainfall amount and OSP, suggests P conservation. The variation in litterfall N, but not litterfall P, in response to rainfall variability reveals a divergent nutrient response along steep changes in water availability in this TDF.

Greenhouses are inflated structures with transparent covering that are used to grow crops under controlled climatic conditions. Crops are protected from extreme climate-related events by being enclosed. Furthermore, the greenhouse design ratio impacts the temperature and humidity distribution profile uniformity as well as the greenhouse. As a result, by effectively designing the greenhouse structure, building materials, dimensions, and shapes, the cost of cooling management strategies can be reduced. Structures with changed arch shapes showed to be more effective at reducing greenhouse cooling demands in hot areas. To demonstrate the tropical region’s inherent capabilities for generating a proper atmosphere for plant development, the optimal temperature, humidity, light, and PH for greenhouse production of crops were supplied. Greenhouse cooling systems are dominated by local environmental characteristics that have an immediate impact on their indoor climatic conditions. Photovoltaic systems in greenhouses have proven technological capacity in real-world settings in this area. This could increase the energy efficiency of some agrivoltaic greenhouse design options.

Mangroves are subject to rapid and large-scale habitat changes, which threaten their unique genetic diversity and provision of critically important ecosystem services. Habitat fragmentation reduces connectivity, which can impair dispersal and lead to genetic isolation. However, it is unclear whether fragmentation could impact mangrove genetic isolation, as mangrove propagules appear to be able to disperse long distances. Here, we conducted a meta-analysis of studies testing for a correlation between geographic distance and genetic distance in mangrove plants. From the 22 studies that met the inclusion criteria, we found a significant isolation-by-distance effect; geographic distance was significantly associated with Nei’s genetic distance and FST. Our results show that mangrove propagules may be limited in their capacity to disperse across long distances, which highlights the importance of maintaining close proximity between habitat patches and reducing habitat fragmentation.

Fire plays a crucial role in shaping plant communities in South American savannas. However, the impact of biotic interactions on tree communities still needs to be better explored. In this study, we evaluated the influence of tree-on-tree interactions and abiotic conditions on the structure and diversity of woody communities in savannas of Central Brazil. We used plots of 10 × 10 m in three preservation areas of savanna to assess the abundance and composition of juveniles and adults in woody communities associated with two Apocynaceae tree species: Hancornia speciosa, postulated to show negative interactions with the associated tree community, and Himatanthus obovatus, postulated to show positive interactions. Our results revealed that while abiotic factors, represented by the altitude, are more critical in shaping the community of juvenile trees, tree-on-tree interactions have a stronger influence on adult tree populations, driving community dynamics during plant recruitment. Specifically, Hancornia speciosa reduces the abundance of adults, whereas Himatanthus obovatus enhances their relative abundance; both shape the composition of tree communities. Consequently, tree-on-tree interactions create distinct mosaics at various stages of regeneration, contributing to savanna dynamics and conservation.

Analysing phenological diversity of tropical trees provides a potential tool to detect climate change effects and devise forest management options. In this study, the leaf phenological activity of 28 dominant tree species in a moist sub-tropical hill forest of north-eastern India was examined for a period of 2 years and related to functional traits (i.e. leaf mass per area (LMA) and wood density (WD)). The peak phase of leaf fall occurred in the cool dry period (November to January) with leaf flush peaking in the pre-monsoon period (February to March), but variation was found between species as influenced by their phenological strategy, i.e. evergreen, leaf-exchanging or deciduous (<4 months leafless). Photoperiod and minimum temperature were the environmental factors most strongly correlated with phenological activity, and the synchrony index within species for both phenophases was 0.81. LMA was less in the deciduous species compared with the evergreen species, whereas WD did not differ. LMA was negatively correlated with the length of deciduousness as well as timing of leaf flush and fall indicating that LMA may be more important than WD in influencing phenological patterns in this forest. The study revealed that the phenological diversity of tropical trees is related to changes in environmental variables and has implication for forest management under changing climate. Further study will help in understanding the phenological response of trees to climatic factors and their potential future changes.

Hypotheses based on allocation theory and herbivore selection offer opposite predictions about how defence levels against herbivores change as the plant tissue grows. The growth differentiation balance hypothesis (GDBH) assumes that defences will be resource-limited in immature tissues and predict that defence levels increase as the plant tissue grows. Conversely, the optimal defence hypothesis (ODH) proposes that plants would have the highest level of defences in the parts that have the highest value in terms of fitness and/or are more frequently attacked by herbivores, such as young tissues. We examine whether spinescence in the shrub Rubus adenotrichos (blackberry) change as the leaf grows, and if this change is consistent with the GDBH or the ODH. We compare the petiole area occupied by prickles, the prickles density and the individual prickle area in mature versus young petioles from Rubus adenotrichos. Our results show that, in R. adenotrichos, young tissues are more protected than mature tissues. Prickles density and the petiole area occupied by prickles were up to 25% higher in young petioles than in mature ones. These results support the ODH, reinforcing the idea that extrinsic factors such as herbivores pressure might drive the change of structural defences level across leaf ontogeny.

Bamboos are mainly distributed in subtropical to tropical areas. Bamboos provide numerous ecosystem services, while the expansion of bamboo gives negative impacts on forest ecosystems. Despite big impacts of bamboos on a forest ecosystem, ecological characteristics of bamboo remain poorly understood. The spatial distributional patterns of three bamboo species, Cephalostachyum pergracile, Bambusa polymorpha, and Dinochloa maclellandii, were studied in a commercial tree plantation of native deciduous tree species in the Bago Mountains, Myanmar. A point process analysis revealed a clumped distribution for each bamboo species. The distributional overlapping of the species was analysed for every pair of two species. The distribution of C. pergracile was little overlapped with those of D. maclellandii and B. polymorpha. Cephalostachyum pergracile was significantly more abundant on gently sloping ridges, whereas D. maclellandii was more abundant on a steeply sloping site. Bambusa polymorpha did not show these patterns with topography. The exclusive distribution of C. pergracile and D. maclellandii may be, at least partly, explained by the opposite topographic preferences of the species. Cephalostachyum pergracile tended to be found far from large trees that cast shade, although B. polymorpha tended to be found with large trees, suggesting that B. polymorpha may be more shade tolerant than C. pergracile. The difference in shade tolerance may contribute to the exclusive distribution of the species. The habitat preference information obtained in this study will contribute to sound bamboo management practices in Myanmar and enable bamboo population sizes to be increased through creation of favourable habitats in forests.

To understand mechanisms behind enigmatic declines of tropical reptiles, knowledge of species interactions and how they vary over space and time is important. Some tropical lizard population dynamics can be highly influenced by egg survival. Yet relatively few studies have examined relationships between lizard reproductive success and egg predators across forest and microhabitat types. In this study, we examined variation in probability of egg depredation, predatory ant abundance, prey availability, and the number of lizards and eggs encountered across four different forest types (abandoned agroforestry, abandoned plantation, secondary forest, and old-growth forest) and three microhabitats (buttress, fallen log, and leaf-litter) at La Selva Biological Station, Costa Rica. Based on previous studies, we made three hypotheses about how lizard egg abundance, egg survival, and predatory ant numbers would be related across microhabitat and forest type. Of these hypotheses, only one was supported: we found more lizard eggs in buttress and fallen log microhabitats than leaf-litter. We did not observe any differences in lizard reproduction or numbers of invertebrates by forest type alone. Based on patterns observed in this study, we suggest that future studies investigating tropical leaf-litter lizard declines focus on environmental variation at the microhabitat scale.

The population of critically endangered white-thighed colobus monkeys (Colobus vellerosus) at Boabeng-Fiema Monkey Sanctuary (BFMS) is possibly the only growing population of this species in West Africa. We assessed the current population status of C. vellerosus in BFMS and the surrounding fragments in Ghana. We undertook a complete count of the population in 2020, and this data was combined with previously conducted complete counts from 1990 to 2014. Results show that the total population growth rate of colobus monkeys at BFMS and the surrounding forest fragments was 353.9% between the 1990 and 2020 censuses (at a rate of 11.8% annually). In the BFMS alone, the total population growth rate was 252.3% between 1990 and 2020 (i.e., at a rate of 8.4% annually). The total population growth rate in the surrounding forest fragments was 97.0% between the first census year of 1997 and the 2020 census (i.e., at a rate of 4.2% annually). The mean group size in the BFMS was 16.7 individuals (SD = 4.0; range = 9–25), while that of the surrounding forest fragments was 14.4 individuals (SD = 4.6; range = 9–23). The overall mean group size was 16.1 individuals (SD = 4.3; range = 9–25). An approximate ratio of one adult male to three adult females (1:3.4) and one adult female to one immature (1:1.2) is an indication that the population of C. vellerosus still has the potential to increase further when new suitable forest fragments are explored in the future. C. vellerosus has the potential to increase further in population in small, suitable fragments if habitat destruction and settlement expansion are managed with primate conservation intentions.

Little is known about the effects of El Niño-Southern Oscillation (ENSO) on tropical insect communities, even though they are suffering rapid declines in complexity and stability due to climate change. We explore the impact of fluctuations in local climate imposed by ENSO on the performance of herbivore defences mediating enemy interactions. In a widespread rainforest edge community, we quantified the mortality caused by five enemy guilds on the immature stages of the herbivorous beetle, Acromis sparsa. ENSO was a significant determinant of beetle mortality. During warmer, drier El Niño years, the survival of beetles decreased. This was due to increased egg parasitism by wasps, which reduced hatching. Additionally, ant predation on beetle larvae increased. Flies and wasps were in competition for larval prey in wetter, cooler La Niña years. Experimental removal of maternal guards or chemical shields revealed which ENSO-related parameters predicted larval mortality. Guarding was most effective against social wasps in La Niña, whereas shields proved most effective in El Niño. Two ENSO-related defence–enemy breakdowns occurred: (1) decoupling whereby the efficacy of a narrow defensive adaptation was reduced to increase mortality, and (2) mismatching whereby the resistance of a narrow defensive adaptation against non-targeted enemies was further reduced to increase mortality. These results highlight that defence efficacy against natural enemies can vary predictably with biotic and abiotic environmental conditions. ENSO events will increase breakdowns in defence-mediated interactions, shifts in competition among enemies, and species loss.

In the vast Neotropic seasonal environment, the most diverse family of bats, the Phyllostomidae (leaf-nosed bats), includes up to 93 species. As the quality and quantity of food resources fluctuate in the habitats, diet heterogeneity is observed among bat species and regions of the Neotropics. In this study, we investigated by faecal analyses, how the dietary niche (DN) of eight Phyllostomidae bat species (Artibeus planirostris, A. fimbriatus, Carollia brevicauda, C. perspicillata, Chiroderma villosum, Glossophaga soricina, Platyrrhinus lineatus, and Sturnira lilium) that occur in a karstic area in the Midwest region of Minas Gerais, Brazil, change in response to seasonal food availability. We recorded the consumption of insects and nine plant families. Moraceae was the most frequent, followed by Piperaceae. Given that seasonal dietary changes can be subtle and hardly noticeable along with fluctuating habitat conditions, we performed the DN decomposition of the eight bats species into subniches, by analysing the data with the WitOMI, which is a decomposition of the niche into temporal subniches. By improving the accuracy and details of the results, we assessed the effects of abiotic (precipitation and environmental temperature) and biotic (quantity and quality of food resources) interactions within the phyllostomid bat community. For each species, we compared niche breadth and overlap and found higher values for the dry season among morphologically similar species. The results of our study suggest that ecologically similar bat species coexist occupying different DNs.

Conversion of primary forest into oil palm plantations is common in tropical countries, affecting soil properties, ecosystem services and land-use management. However, little is known about the short-range spatial soil distribution that is important for soil scientists, ecologists, entomologists, mycologists or microbiologists. In this study, seven soil properties (pH, EC (µS/m), P (mg/kg), NO3- (mg/kg), N%, C% and C:N) were measured to quantify the spatial autocorrelation across primary forest, selectively logged forest and oil palm plantation in Sabah, Malaysian Borneo. Local variograms were calculated (range ∼5 m) to determine the short-range variation, and a decision tree as well as principal component analysis were implemented to determine if the overall (global) mean differed between land uses. As hypothesised, oil palm soils deviated the most from primary forest soils, which had more fluctuating variograms and in general, a shorter range. Oil palm plantations also showed a difference in the global mean except for electrical conductivity. Selectively logged forests also differed in their short-range spatial structure; however, the global mean and variance remained similar to primary forest soil with the exception of labile phosphorus and nitrate. These results were attributed to initial plantation development, removal of topsoil, fertiliser application and topography.

Itaipu Hydroelectric Power Plant initiated a large reforestation programme after the expropriation of the areas destined for the formation of the reservoir. This study aimed to evaluate the effectiveness of forest restoration of the Seasonal Semideciduous Forest in the Upper Paraná Atlantic Forest ecoregion, Brazil, using epigaeic ant assemblages as bioindicators, by comparing ant species richness and composition in the Reservoir Protection Strip with adjacent areas, such as the primary forest of the Iguaçu National Park and the Permanent Preservation Area located on a rural property and agricultural areas. In total, 171 ant species were identified. Ant species richness was higher in forest than in agricultural areas and did not differ among forest areas. However, ant species composition in forest areas, regardless of the restoration technique used, was not similar to the primary forest, possibly due to variation in forest recovery time. This study highlights the great value of the Iguaçu National Park as a conservation unit. Also, it reveals that the efforts for the creation and maintenance of the Reservoir Protection Strip, which remains without anthropic interventions for years, might indeed lead to a complete recovery of the ant species composition over time, reinforcing their great importance for biodiversity conservation.

Primate communities vary in their level of redundancy, or overlap, in seed dispersal function, which could be due to body size, degree of frugivory or intraspecific variation, among other factors. In this study, we quantified redundancy in seed dispersal among three sympatric primate species: Lagothrix lagothricha, Alouatta seniculus and Sapajus apella in gallery forests in Meta, Colombia. We compared the median seed width dispersed and the number and species richness of large (≥5.9 mm wide) and very large (>7.5 mm wide) seeds per faecal sample. The medium-sized, highly folivorous A. seniculus mostly dispersed large seeds, the larger, highly frugivorous L. lagothricha dispersed very large and small seeds, and the smaller, partially frugivorous S. apella dispersed the smallest seeds. However, for L. lagothricha and S. apella, we did not find the expected results that adults disperse larger seeds than juveniles. Across species, there is complementarity in seed dispersal in relation to seed size, with L. lagothricha being unique in its contribution to the dispersal of very large seeds both in terms of quantity and richness.

Biological invasions are a threat to protected areas globally; however, the relative lack of studies quantifying the ecological impacts impairs informed decision-making. We selected three annual alien plants, widespread in the riparian habitats of the Kruger National Park, South Africa: Datura innoxia, Parthenium hysterophorus, and Xanthium strumarium, to examine their potential impacts on riparian plant communities. We identified 12–13 populations for each and placed a pair of invaded and uninvaded plots in each population. Species richness, Shannon diversity, and Pielou evenness were compared between the invaded and uninvaded plots using LMM models, and species composition was compared using ordination. The invaded vegetation showed lower species richness compared to the uninvaded, with the strongest effect observed for P. hysterophorus. The invaded plots also showed lower Shannon diversity and Pielou evenness due to the presence of alien dominants. For all three invaders, the invasion resulted in changes in the composition of native vegetation. Some native plants were more frequent and abundant in the invaded vegetation, possibly due to the habitats created in sandy river beds. The native species richness decreased with increasing invader cover, but the species richness of aliens accompanying the invasive dominants was not negatively affected by their cover. Our results confirmed the negative impact of invasive aliens on native plant diversity, with the most pronounced effect by Parthenium hysterophorus invasions.

Gypsophily, i.e. the relationship between plants and gypsum soils, has been extensively studied only in arid and semi-arid regions, in contrast to tropical areas, where gypsum outcrops act as refugia for xerothermophilic species and endemic flora. We focused on gypsophile flora in Campeche, Mexico on the Zoh-Laguna Plateau. Using a combination of remote sensing, literature review, and herbarium databases, we identified 14 potential gypsum outcrops and compiled a list of vascular plant species with the potential to grow in gypsum soils in Campeche (151 total species: three probable gypsophiles and endemic to YP, 148 gypsovags). Nine of the 14 potential gypsum outcrops remain unexplored botanically, and 18 species in the final checklist were not previously reported to have an affinity for gypsum soils. This study is the first to confirm the presence of gypsum and report its concentration in the evaluated soils; gypsum content in the soils reached 51%, much higher than the commonly accepted 25%. Our results on gypsum soils and associated vegetation confirm the need for more extensive gypsophily studies in tropical zones.