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Increased air pollution in a number of developing African countries, together with the reports of vegetation damage typically associated with acid precipitation in commercial forests in South Africa, has raised concerns over the potential impacts of acid rain on natural vegetation in these countries. Recalcitrant (i.e. desiccation sensitive) seeds of many indigenous African species, e.g. must germinate shortly after shedding and hence, may not be able to avoid exposure to acid rain in polluted areas. This study investigated the effects of simulated acid rain (rainwater with pH adjusted to pH 3.0 and 4.5 with 70:30, H2 SO4 :HNO3 ) on germination, seedling growth and oxidative metabolism in a recalcitrant-seeded African tree species Trichilia dregeana Sond., growing in its natural seed bank. The results suggest that acid rain did not compromise T. dregeana seed germination and seedling establishment significantly, relative to the control (non-acidified rainwater). However, pH 3.0 treated seedlings exhibited signs of stress typically associated with acid rain: leaf tip necrosis, abnormal bilobed leaf tips, leaf necrotic spots and chlorosis, reduced leaf chlorophyll concentration, increased stomatal density and indications of oxidative stress. This may explain why total and root biomass of pH 3.0 treated seedlings were significantly lower than the control. Acid rain also induced changes in the species composition and relative abundance of the different life forms emerging from T. dregeana's natural seed bank and in this way could indirectly impact on T. dregeana seedling establishment success.

ABSTRACT. The gap between scientific knowledge and implementation in the fields of biodiversity conservation, environmental management, and climate change adaptation has resulted in many calls from practitioners and academics to provide practical solutions responding effectively to the risks and opportunities of global environmental change, e.g., Future Earth. We present a framework to guide the implementation of science-action partnerships based on a real-world case study of a partnership between a local municipality and an academic institution to bridge the science-action gap in the eThekwini Municipal Area, South Africa. This partnership aims to inform the implementation of sustainable land-use planning, biodiversity conservation, environmental management, and climate change adaptation practice and contributes to the development of human capacity in these areas of expertise. Using a transdisciplinary approach, implementation-driven research is being conducted to develop several decision-making products to better inform land-use planning and management. Lessons learned through this partnership are synthesized and presented as a framework of enabling actions operating at different levels, from the individual to the interorganizational. Enabling actions include putting in place enabling organizational preconditions, assembling a functional well-structured team, and actively building interpersonal and individual collaborative capacity. Lessons learned in the case study emphasize the importance of building collaborative capacity and social capital, and paying attention to the process of transdisciplinary research to achieve more tangible science, management, and policy objectives in science-action partnerships. By documenting and reflecting on the process, this case study provides conceptual and practical guidance on bridging the science-action gap through partnerships.

Aim While there is a huge macroecological and biogeographical literature addressing endemism, very little has been done to systematically study lineages that are widely distributed across the globe. Our aim here was to list and analyse those lineages of terrestrial tetrapod vertebrates found in 60-90% of the world, loosely termed here as cosmopolitan.Methods Two sets of geographical units and three occupancy criteria were used to list, analyse and map cosmopolitan lineages and their sister lineages.Results Among the 83 lineages identified, 2 were represented by amphibians, 9 by reptiles, 13 by mammals, and the remainder by birds, of which 12 were passerines and 47 were non-passerines. All these lineages are present in parts of Southeast Asia, most of them throughout much of Eurasia and Africa, but fewer in South America and very few in Australia. Only three of the lineages (all reptiles) are likely to exemplify vicariance or early dispersal-driven cosmopolitanism, the rest having attained world-wide distribution via extensive, geologically recent dispersal. The distribution of sister lineages indicates that many cosmopolitan lineages probably originated in the savanna regions of Africa, some in Southeast Asia, and fewer in tropical America.Main conclusions Cosmopolitan distributions in tetrapods are primarily the result of dispersal, with large body size and the ability to fly being two key correlates of rapid global colonization. We argue that a cosmopolitan lineage framework in biogeographical and ecological studies could add great depth to the understanding of evolutionary success, and would be highly relevant to the field of invasion biology.

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Although world’s zoogeographical regions have been repeatedly confirmed using various clustering techniques, this has not yet been done in the case of world’s floral kingdoms, due to the absence of complete and accurate distributional data sets. Here we use the distribution of 65 broad seed plant lineages across 37 regions to test for global relationships. We find support for the existence of distinct Austral, Holotropical, and Holarctic clusters. The existence of an Austral kingdom has long been considered to be one of the major differences between plant and animal regionalisation patterns. However, the homogeneity of the Holotropical cluster can be viewed as a relatively novel result.

The current distribution of biotic lineages that emerged in the deep time has both theoretical and practical implications, in particular for understanding the processes that have forged present-day biodiversity and informing local and regional-scale conservation efforts. To date however, there has been no examination of such patterns globally across taxa and geological time. Here we map the diversity of selected extant seed plant and tetrapod vertebrate lineages that were already in existence either in the latest Triassic or latest Cretaceous. For Triassic-age linages, we find concentrations in several regions – both tropical and temperate – parts of North America, Europe, East and South-east Asia, northern South America, and New Zealand. With Cretaceous-age lineages, high values are relatively uniformly distributed across the tropics, with peak the values along the Andes, in South-east Asia and Queensland, but also in the temperate Cape Mountains. These patterns result from a combination of factors, including land area, geographic isolation, climate stability and mass extinction survival ability. While the need to protect many of these lineages has been long recognised, a spatially-explicit approach is critical for understanding and maintaining the factors responsible for their persistence, and this will need to be taken forward across finer scales.