Areas Requiring Restoration Efforts are a Complementary Opportunity to Support the Demand for Pollination Services in Brazil

Crop pollination is one of Nature's Contributions to People (NCP) that reconciles biodiversity conservation and agricultural production. NCP benefits vary across space, including among distinct political-administrative levels within nations. Moreover, initiatives to restore ecosystems may enhance NCP provision, such as crop pollination delivered by native pollinators. We mapped crop pollination demand (PD), diversity of pollinator-dependent crops, and vegetation deficit (VD) (vis-a-vis Brazilian legal requirements) across all 5570 municipalities in Brazil. Pollinator-dependent crops represented ∼55% of the annual monetary value of agricultural production and ∼15% of the annual crop production. Municipalities with greater crop PD (i.e., higher degree of pollinator dependence of crop production) also had greater VD, associated with large properties and monocultures. In contrast, municipalities with a greater diversity of pollinator-dependent crops and predominantly small properties presented a smaller VD. Our results support that ecological restoration prompted by legal requirements offers great potential to promote crop productivity in larger properties. Moreover, conservation of vegetation remnants could support food security in small properties. We provided the first steps to identify spatial patterns linking biodiversity conservation and pollination service. Using Brazilian legal requirements as an example, we show that land-use management policies may be successfully used to ensure agricultural sustainability and crop production.

Seasonal rhythms of seed rain and seedling emergence in two tropical rain forests in southern Brazil

Seasonal tropical forests show rhythms in reproductive activities due to water stress during dry seasons. If both seed dispersal and seed germination occur in the best environmental conditions, mortality will be minimised and forest regeneration will occur. To evaluate whether non-seasonal forests also show rhythms, for 2 years we studied the seed rain and seedling emergence in two sandy coastal forests (flooded and unflooded) in southern Brazil. In each forest, one 100 x 30-m grid was marked and inside it 30 stations comprising two seed traps (0.5 x 0.5 m each) and one plot (2 x 2 m) were established for monthly monitoring of seed rain and a seedling emergence study, respectively. Despite differences in soil moisture and incident light on the understorey, flooded and unflooded forests had similar dispersal and germination patterns. Seed rain was seasonal and bimodal (peaks at the end of the wetter season and in the less wet season) and seedling emergence was seasonal and unimodal (peaking in the wetter season). Approximately 57% of the total species number had seedling emergence 4 or more months after dispersal. Therefore, both seed dormancy and the timing of seed dispersal drive the rhythm of seedling emergence in these forests. The peak in germination occurs in the wetter season, when soil fertility is higher and other phenological events also occur. The strong seasonality in these plant communities, even in this weakly seasonal climate, suggests that factors such as daylength, plant sensitivity to small changes in the environment (e.g. water and nutrient availability) or phylogenetic constraints cause seasonal rhythms in the plants.

Breeding system and floral morphometry of distylous Psychotria L. species in the Atlantic rain forest, SE Brazil

General patterns of floral morphology and incompatibility mechanisms have been described for many distylous plants. The absence of these patterns in typically distylous groups, as observed especially in tropical environments, is interpreted as atypical distyly, or as a new reproductive strategy derived from it. Data are presented here on the morphological and compatibility relations between floral morphs of four Psychotria dimorphic species in the Atlantic rain forest in SE Brazil: Psychotria jasminoides, P. birotula, P. mapourioides, and P. pubigera. When significant differences were found, floral parts were larger in thrum flowers. Results of controlled crosses showed that most incompatible pollen tubes were arrested in the stigma, and only in a low proportion in the upper parts of the style. We conclude that, at the study site, the majority and most important morphological and mating features of typical distyly seem to be conserved in P. jasminoides and P. mapourioides, which presented reciprocal herkogamy, self and intramorph incompatibility, and a balanced morph ratio in the population. Typical distyly in P. birotula is supported by floral morphology, pollen tube data and morph ratio and, in P. pubigera, only by floral morphology and pollen tube data.