ASSESSING GALLERY FOREST ECOSYSTEMS - CASE STUDY OF THE PAJEÚ GALLERY FOREST

Madagascar's unique dry forests, particularly gallery and spiny forests, face severe threats and are significantly understudied, leaving only a fraction of the original extent intact. Thus, there is a critical need for characterizing, conserving, and restoring this diverse forest ecosystem. Conducting extensive floristic surveys and environmental analyses, we investigated structural and compositional differences between the gallery and spiny forests, as well as within distinct gallery forest sites in Berenty Reserve in the south of the island. We also evaluated differences in habitat quality between the spiny and gallery forests for three species of diurnal lemurs in the reserve, and analyzed the current population trend of the tamarind trees, a species of ecological and cultural importance in Madagascar. Our findings revealed that the spiny and gallery forests differed in composition and structure, confirming the unique ecological characteristics of gallery forests and the underexplored richness of spiny forests. Spiny forests exhibited higher species richness despite a comparatively lower sampling effort, emphasizing the need for focused conservation efforts in these overlooked ecosystems. Tamarind populations, vital for lemur nutrition, showed signs of inadequate regeneration suggesting a recruitment bottleneck, possibly due to factors like a lowering water table, brown lemur foraging habits, or shifts in environmental conditions. Urgent interventions, including enrichment plantations, were recommended to ensure the survival of this keystone species. Contrasting botanical and lemur-centric perspectives revealed that while spiny and gallery forests differed botanically, they offered comparable habitat quality for ring-tailed and sifaka lemurs. However, brown lemurs exhibit a preference for the gallery forest, highlighting the intricate relationship between plant composition and lemur habitat choices. Our study underscores the urgency of expanding our knowledge of Madagascar´s dry forests, and Berenty Reserve, as one of the few remaining protected areas with gallery and spiny forests, serves as a reference for future research in Madagascar's understudied ecosystems.

We investigated spatial and temporal differences in the habitat associations of five New World vulture taxa (family Vulturidae auct. Cathartidae) in the Llanos of central Venezuela. Overall numbers of vultures were higher over open or semi-open savanna habitats than closed canopy riverine gallery forest. Black Vultures Coragyps atratus brasiliensis and Lesser Yellow-headed Vultures Cathartes burrovianus foraged principally in open habitats at all times. Although King Vultures Sarcoramphus papa were counted mainly over gallery forest they also sometimes foraged outside the forest area. During the wet season, resident Turkey Vultures Cathartes aura ruficollis foraged in all habitats but highest densities occurred over gallery forest, east of the main highway. This indicated that, to some extent, vulture species were ecologically segregated by habitat. During the dry season, a larger, dominant, migratory race of Turkey Vulture, C. a. meridionalis, coexisted with the resident subspecies. Migrants foraged at highest densities over open and semi-open habitats, but they also occurred in low numbers over gallery forest. When sympatric with these migrants, resident Turkey Vultures foraged almost exclusively in closed gallery and semi-deciduous tropical forest to the east of the highway, and, in contrast to the wet season, avoided open habitats. At the end of the dry season (March to April), migrant Turkey Vultures departed for North America to breed, resulting in a dramatic reduction in densities of Cathartes vultures. Despite the absence of migrants, densities of Cathartes vultures remained higher in open and semi-open savanna habitats than the gallery forest area. Support for a possible niche shift came from the proportion of carcasses visited in different habitats by resident Turkey Vultures, habitat sightings of wing-tagged birds and radiotracking studies.

O estudo foi realizado na Fazenda Água Limpa, DF, em três fisionomias: Cerrado típico, mata de galeria e povoamento de Eucalyptus urograndis, e teve por objetivo analisar o conteúdo de macro e micronutrientes via estoque de serapilheira, durante as épocas seca e chuvosa. Procedeu-se a coleta mensal de serapilheira no período de setembro de 2011 a agosto de 2012. As amostras foram coletadas aleatoriamente, com três repetições em cada fisionomia sendo secas para posterior determinação dos teores de nutrientes. Os resultados foram avaliados por análise de variância, teste de Tukey e correlação de Pearson. Os conteúdos de macronutrientes no estoque de serapilheira na Mata de Galeria e eucalipto apresentaram-se na ordem de N > Ca > K > Mg > S > P no período chuvoso, e no seco o S foi superior ao Mg para o eucalipto, não sendo observada alteração na Mata de Galeria. No Cerrado típico, a ordem foi N > Ca > S > Mg > K > P no período chuvoso, alterando para N > Ca > K > S > Mg > P no período seco.

This study aimed to determine the impact of land use and illegal activities on elephant distributions in 2003, 2015, and 2021. Geospatial data inclusion satellite images of different characteristics were used as well as aerial count of animals along linear transects of varying widths. Using ArcMap 10.8, we laid grilles of 100 km2 covering the entire study area. We performed clipping to display and estimate the area of elephant’s occupancy in each grid. As such, we were able to determine the number of elephants and the number of illegal activities in each grid. Correlation analysis were performed to understand relationships between elephants’ number and land-use units as well as the illegal activities. The identified different land use units were: rainfed crop, gallery forest, Wooded savanna, shrubby savanna, grass savanna, and water surface. Of the variables studied, only annual crop, gallery forest, shrubby savanna and illegal activities were significantly correlated with elephant numbers. Annual crop and illegal activities were negatively correlated with elephant numbers, while gallery forest and shrubby savanna were positively correlated with elephant abundance. These results confirmed that water, forage and serenity are the main factors that explain the distribution of elephant in protected areas.

Sesbania virgata (Cav.) Pers. is a pioneer species native to South America able to release allelochemicals that affect germination and development of other plant species. The aim of this work was to evaluate the allelopathic effect of S. virgata on the germination and development of co-occurring species from gallery forest and on agronomic species. Two forest native species, Enterolobium contortisiliquum (Vell.) Morong and Sapindus saponaria L., and two agronomic species (these as control), Oryza sativa L. and Solanum lycopersicum L. were used in the lab and greenhouse assays with seeds and leaf extracts of S. virgata. Agronomic species were more affected than native species when co-germinated with seeds of S. virgata. The germination percentage and speed germination index of the agronomic species were reduced in both in vitro and greenhouse assays. In the same assays, the seeds of native species showed no significant differences in the parameters mentioned. However, the initial growth of the four species assayed was affected, with reduction in plant length and shoot diameter followed by significant reduction in plantlet shoot and root weights. In the assays with irrigation of S. virgata leaf extracts, no significant inhibitory effects on germination were observed for all species. Height and shoot diameter of the native species were not affected by the leaf extracts, nor were fresh and dry weights. However, these parameters increased in the agronomic species as they were irrigated with leaf extracts. Based on our data we conclude that seed leachates of S. virgata affect germination and seedling development of other species, suggesting that its invasive behavior is due mainly to seed allelochemicals. Although with less pronounced effects on native species, allelopathy of S. virgata might also influence Interspecific competition in its natural environment.

A 7000-year pollen record of a 90 cm core from Chenevo (4°05'N, 70°21'W, 150 m alttitude) and a 3500-year pollen record of a 285 cm core from Mozambique (3°58 N, 73°03 W, 175 m altitude) both from the savannas of the Llanos Orientales, Colombia, are presented. The records show dynamics between open savanna (Poaceae, Cyperaceae), woody savanna (Byrsonima, Curatella, Didymopanax), palm swamp (Mauritia, Mauritiella), forest and gallery forest taxa. These re' ect plant available moisture, and more latterly human impact. The record from Chenevo shows: from 7260 to 6930 14C yr BP, open savanna vegetation and gallery forest along the drainage system; from 6930 to 4000 14C yr BP, forest and gallery forest expanded; from 5500 14C yr BP, Mauritia palm forest increased and particularly so from 4000 to 2380 14C yr BP also in combination with gallery forest expansion; from 2380 14C yr BP to present-day gallery forest, Mauritia and Mauritiella palm forest is most abundant. The record from Mozambique is hampered by 14C reversals, but appears to show the following development: from 3440 to 610 14C yr BP abundant Mauritia swamp forest; from 600 14C yr BP Mauritia swamp forest was replaced by gallery forest in which Byttneria, Mimosa and Sapindaceae are present; from 600 to 350 14C yr BP, gallery forest replaced woody grass savanna; during the last 350 14C yr BP, savanna increased and gallery forest decreased, as Cecropia, Mauritia and Zea mays point to human impact. Comparison of pollen records from six savanna lakes located along 400 km east–west transect (Sardinas, Angel, El Piñal, Carimagua, Chenevo and Mozambique) shows the following regional vegetation and climate development. From 18000 to 10700 14C yr BP, patchy gallery forest, non-permanent lake conditions and maximum abundance of grasses re' ect low precipitation and long dry seasons. From 10700 to 9700 14C yr BP, gallery forest expansion re' ects a more humid climate. From 9700 to 5800 14C yr BP, grasslands were at a maximum, re' ecting dry climatic conditions. From 5800 to 3800 14C yr BP, gallery forest increased. Around 4000 14C yr BP, the savanna ecosystem changed in all records presented: particularly the palms Euterpe/Geonoma Mauritia and Mauritiella became abundant in the savanna ecosystem, this may be indicative of human impact on the savanna ecosystem.

Phenological studies were carried out in gallery and montane forests along the Lencois River in the Chapada Diamantina mountains, state of Bahia, Brazil, between January 1993 and March 1998. Leaf flush, leaf fall, flowering, and fruiting were followed in 54 tree species (N = 243 trees tagged along trails following the river margin and the valley sides). Both gallery and montane forests exhibited a moderate peak in leaf fall during the dry season (August–October), as well as increased leaf flushing in the rainy season (December–April). Three basic modes of leafing activity were noted, although most trees in the gallery forest and in the montane forest were evergreen (82.3 and 57.8% relative frequency, respectively). In both forest types, flowering and fruiting modes were annual, with peaks of activity during the rainy season. The predominantly evergreen mode of leaf fall and leaf flush found in this study was most similar to that seen in tropical wet forests, while the flowering and fruiting modes...

Plant Diversity and hydrological relations to groundwater in the riparian zone of Cerrado in Mato Grosso (Brazil)

Vegetation-rainfall coupling as an indicator of ecosystem state in a heterogeneous landscape

Unlike other toucan species, the Toco toucan (Ramphastos toco)--the largest Ramphastidae--usually inhabits dry semi-open areas. This conspicuous canopy frugivore uses a large home range that includes a variety of vegetation types, among which gallery forests are widely cited as important to this species. However, the factors relating to the occurrence of Toco toucans in such habitats are unclear. I studied the abundance of Toco toucans as well as the availability of fleshy fruit in a gallery forest in the southern Pantanal (sub-region of Miranda, Brazil), in order to assess the relationship between these parameters. Also, I examined toucan foraging activity to analyze its relationship with both toucan abundance and fruit availability. The presence of the Toco toucan was more common in the gallery forest from the middle to the end of the dry season and during the middle of the wet season. Toucans foraged for fleshy fruits, mainly Genipa americana, Ficus luschnatiana, and Cecropia pachystachya fruits, feeding mostly on G. americana (by far the favorite food resource) and F. luschnatiana fruits during the dry season, while C. pachystachya fruits were important in the wet season. Toco toucans foraged particularly heavily (> 80% of foraging activity) on G. americana fruits during the latter part of the dry season, when fleshy fruit availability declined sharply. Toco toucan abundance in the gallery forest was associated with the availability of the most commonly consumed fleshy fruits, and also with its foraging activity. This finding suggests that the Toco toucan moved to the gallery forest periodically in response to the availability of abundant food resources, especially the G. americana fruits widely available and exploited during the severely dry season. Therefore, these fruits potentially contribute to Toco toucan persistence in the South Pantanal during the harshest period of the year.

Earthworm functional group assemblages vary with land cover/use in human-impacted landscapes of Sudano-Guinean area, Cameroon

This study assesses land cover change of the Koupa Matapit forest gallery, West Cameroon, in relation to anthropogenic factors. Ethnobotanical surveys were conducted to investigate the relationships between the local population and the gallery forest; the spatio-temporal dynamics of the landscapes around the gallery forest were studied from the diachronic analysis of three Landsat TM satellite images of 1984, Landsat ETM + 1999 and Landsat OLI_TIRS of 2016, supplemented by verification missions on field. The satellite images were processed using ArcGIS and Erdas Imagine software. According to surveys, it should be noted that agriculture and livestock are the main economic activities of the population of Koupa Matapit, agriculture and fuel wood collection for energy were the main anthropogenic activities responsible for deforestation and degradation of the forest gallery. The collection of non-timber forest products (NTFPs) would have a significant implication in land use and cover changes. The results indicate that the extension of savannah/agricultural land (from 6989 ha in 1984 to 7604 ha in 2016) and bare soil/built up area (from 71 ha in 1984 to 342 ha in 2016) would have led to the disappearance of much of the forest area (1465 ha in 1984 to 580 ha in 2016). The rapid population growth of Koupa Matapit would be responsible for these pressures. There is an urgent need to implement appropriate land use policy in this area.

Anthropogenic activities have led to changes in land use resulting in fragmented areas with a reduction of biodiversity and ecosystem services. Gallery forests and live fences are common elements in Neotropical agricultural landscapes that could contribute to the conservation of bird species and the services they provide. However, we need to better understand how different tree cover types influence bird assemblages in order to conserve biodiversity. I analysed the diversity of bird assemblages in space and time across two cover types in three agricultural-livestock farms in Guanacaste, Costa Rica. Bird assemblages were sampled during 2019 using transects, covering both the dry and rainy season. I estimated richness and relative abundance of bird assemblages at each tree cover type and site. To characterize vegetation structure, I calculated plant richness, diameter at breast height and tree height. Patterns in bird diversity changed at a spatial scale, whereas remained similar in time. Bird assemblages had consistently higher richness and abundance in live fence than in gallery forest in the three study sites. In addition, live fences resulted in a less structural complexity compared to gallery forest, as indicated by decreased plant richness and tree height. My results show that live fences play an important role for birds, allowing for more diverse avian assemblages in human-modified ecosystems. Although live fences are less structurally complex and may offer less suitable habitats for birds than gallery forests, they might provide complementary food resources and act as stepping-stones for both resident and migratory bird species. Thus, live fences may perform as corridors for birds increasing connectivity in rural landscapes, which make them an essential tool for bird conservation.

Gallery forests harbor mammals and sand flies that may be involved in the transmission of Leishmania spp. parasites. Characterizing the enzootic cycles of Leishmania spp. is essential for understanding its transmission dynamics. We analyzed the presence of Leishmania spp. in mammals and sand flies in gallery forests during the dry season in the Cerrado. Four gallery forests were investigated in May and September 2014. Our capture effort included 1,280 HP trap-nights, 16 Shannon trap-nights for sand flies, and 5,120 trap-nights for mammals. After identifying the mammalian and sand fly species, SSU rRNA and ITS-1 polymerase chain reaction (PCR) were used to detect Leishmania spp. A total of 1,209 sand flies belonging to 13 species were captured, mainly Bichromomyia flaviscutellata. Leishmania spp. DNA was not detected in the analyzed sand fly females. PCR analysis of 153 mammals revealed Leishmania spp. in 20 samples (13%) in May (early dry season), when the infection rate was 31% in one gallery forest. The host species were Rhipidomys macrurus, Gracilinanus agilis, and Didelphis albiventris. We observed a low frequency of mammals infected with Leishmania spp., which was not detected in sand flies. Our results indicate that Leishmania spp. infection is higher in mammals during the early dry season in Cerrado gallery forests.

The Cerrado Biome comprises many habitats, the most common being the savanna type. This biome presents an intense dry season that imposes difficulties on organism survival. The Cerrado’s wet season is the period of greatest abundance and richness of species, including the Lepidoptera. In Brazil, most studies on Nymphalidae seasonality have been conducted in biomes other than the Cerrado. Thus, the pattern of the Nymphalidae seasonality in the Cerrado is unknown. The aim of this study was to describe the temporal dynamics of these butterflies in both savanna and gallery forest habitats in the Cerrado, comparing our findings to those previously reported from other Brazilian biomes, and to discuss the effects of weather and habitat structure on temporal dynamics. Thirty bait-traps were distributed in 2 vertical strata (understory and canopy) in each habitat type (savanna and gallery forest; thus, 60 bait-traps were distributed during 6 d each month from Jul 2012 to Jun 2013. In total, 3,459 individuals of 62 species were captured. The transition between the wet and dry season presented the greatest abundance and species richness and was the period of lowest evenness in the Nymphalidae community. Two distinct assemblages were found in the savanna and gallery forest. Moreover, greater butterfly species turnover was found over time in the gallery forest than in the savanna habitat. These results highlight the importance of climatic seasons, plant phenology, and habitat structure as important predictors of the temporal dynamics of these butterflies in the Cerrado Biome. Furthermore, the floristic and structural distinctiveness of the savanna and gallery forest, and the biological requirements of the butterfly species, could explain a large portion of the species turnover observed in the gallery forest.