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The Amazonian region is composed by many kinds of environments, including the Amazonian savannas, which comprise about 5% of the Amazon biome in Brazil. The biota of Amazonian savannas is poorly known, especially for insects. In this study, we performed a faunistic inventory of flesh flies (Diptera: Sarcophagidae) of four Brazilian Amazon savannas, where we recorded two subfamilies, 16 genera, and 40 species, two of which are described as new to science: Lepidodexia (Notochaeta) helenae sp. nov. and Lipoptilocnema augustoi sp. nov. Oxysarcodexia graminifolia Souza, Pape & Thyssen, 2020 is recorded for the first time for Brazil. Dexosarcophaga paulistana Lopes (1982), Helicobia biplagiata Dodge, 1966, Helicobia cearensis Tibana, 1976, Oxysarcodexia simplicoides (Lopes, 1933), and Oxyvinia excisa (Lopes, 1950) are newly recorded for the Brazilian Amazon. Oxysarcodexia nitida Soares & Mello-Patiu, 2010 is a new record for the state of Para. The species D. paulistana is redescribed, and photographs and detailed illustrations of male terminalia are provided.

Free-living N.sub.2 fixation is an important pathway of external nitrogen input to natural terrestrial ecosystems. However, few measurements of N.sub.2 fixation have been conducted in shrublands. Here, free-living N.sub.2 fixation in soil (or soil N.sub.2 fixation) and litter (or litter N.sub.2 fixation) in three shrublands was measured in a karst catchment, southwest China. The three shrublands were dominated by Pterolobium punctatum Hemsl., Vitex negundo Linn. and Rhus chinensis Mill., respectively. Field measurements were carried out in January and July 2016, respectively, using acetylene reduction assay. N.sub.2 fixation had distinct patterns among shrublands or between seasons. In January, no difference was found for soil N.sub.2 fixation among the three shrublands, but litter N.sub.2 fixation rate was highest in R. chinensis and lowest in P. punctatum. In July, soil N.sub.2 fixation rate was highest in R. chinensis and lowest in P. punctatum, but litter N.sub.2 fixation was significantly lower in P. punctatum than in the other two shrublands. Across the two seasons, soil N.sub.2 fixation rate in R. chinensis was 31% greater than that in P. punctatum, and litter N.sub.2 fixation rates in V. negundo and R. chinensis were 13 and 16 times greater than the rate in P. punctatum, respectively. Both soil and litter N.sub.2 fixation rates were similar between the two seasons in P. punctatum, but the rates were significantly higher in July than in January in the other two shrublands. Annual N.sub.2 fixation rates were estimated to vary from 0.63 ± 0.07 to 0.97 ± 0.08 kg N ha.sup.-1 y.sup.-1 for the three shrublands. The strongest explanatory variable for soil N.sub.2 fixation was total nitrogen in July; and that for litter N.sub.2 fixation was nitrogen in January, but was C:N ratio in July. Our findings suggest that large variation in N.sub.2 fixation may occur among shrublands within a small scale, and hence, more measurements are needed to get a representative range of N.sub.2 fixation rates for the shrubland biome.

Biomass burning represents both a significant and highly variable source of NO.sub.x to the atmosphere. This variability stems from both the episodic nature of fires, and from fire conditions such as the modified combustion efficiency of the fire, the nitrogen content of the fuel and possibly other factors that have not been identified or evaluated by comparison with observations. Satellite instruments offer an opportunity to observe emissions from wildfires, providing a large suite of measurements which allow us to study mean behavior and variability on the regional scale in a statistically rigorous manner. Here we use space-based measurements of fire radiative power from the Moderate Resolution Imaging Spectroradiometer in combination with NO.sub.2 tropospheric column densities from the Ozone Monitoring Instrument to measure mean emission coefficients (ECs in g NO MJ.sup.−1) from fires for global biomes, and across a wide range of smaller-scale ecoregions, defined as spatially-distinct clusters of fires with similar fuel type. Mean ECs for all biomes fall between 0.250-0.362 g NO MJ.sup.-1, a range that is smaller than found in previous studies of biome-scale emission factors. The majority of ecoregion ECs fall within or near this range, implying that under most conditions, mean fire emissions of NO.sub.x per unit energy are similar between different regions regardless of fuel type or spatial variability. In contrast to these similarities, we find that about 24% of individual ecoregion ECs deviate significantly (with 95% confidence) from the mean EC for the associated biome, and a similar number of ecoregion ECs falls outside the range of all mean biome ECs, implying that there are some regions where fuel type-specific global emission parameterizations fail to capture local fire NO.sub.x emissions.

The state of Mato Grosso do Sul, Brazil is an important region of South America regarding leishmaniasis, with the great diversity of sandflies reported since 1938 and wide biodiversity represented by its biomes (Atlantic Forest, Cerrado, and Pantanal). A checklist of sandflies is presented here for the state and respective biomes. The data base was compiled from primary and secondary data. The primary data collection involved automatic light traps at Miranda-Abobral Pantanal subregion and in subregion Baixa Nhecolancia of Pantanal. The secondary data were obtained from entomology scientific collections and a literature review of articles from 1938 to 2019, including entomological museum collections. A total of 71 species were reported, belonging to 14 genera and 13 subgenera, in 61 municipalities of the state, including the type locality of 9 species, and the first report of Lutzomyia cruzi (Mangabeira 1938), vector of Leishmania infantum (Nicolle 1937), in the Pantanal region of Miranda-Abobral. Other vector species, Bichromomyia flaviscutellata (Mangabeira 1942), Lutzomyia longipalpis (Lutz & Neiva 1912), Nyssomyia antunesi (Coutinho 1939), Nyssomyia intermedia (Lutz & Neiva 1912), Nyssomyia neivai (Pinto 1926), and Nyssomyia whitmani (Antunes & Coutinho 1939), are reported in the entire area of the state. Maps containing the distribution of sandflies on Mato Grosso do Sul biomes were produced. The eclecticism of the species in relation to their ecotypes was observed, with several species using the three biome types as habitats and breeding sites.

A biome is a key community ecological and biogeographical concept and, as such, has profited from the overall progress of community ecology, punctuated by two major innovations: shifting the focus from pure pattern description to understanding functionality, and changing the approach from observational to explanatory and,most importantly, from descriptive to predictive. The functional focus enabled development of mechanistic and function-focused predictive and retrodictive modelling; it also shaped the current understanding of the concept of a biome as a dynamic biological entity having many aspects, with deep roots in the evolutionary past, and which is undergoing change. The evolution of the biome concept was punctuated by three synthetic steps: the first synthesis formulated a solid body of theory explaining the ecological and biogeographical meaning of zonality and collated our knowledge on drivers of vegetation patterns at large spatial scales; the second translated this knowledge into effective mechanistic modelling tools, developing further the link between ecosystem functionality and biogeography; and the third (still in progress) is seeking common ground between large-scale ecological and biogeographic phenomena, using macroecology and macroevolutionary research tools.

Moss-associated N.sub.2 fixation provides a substantial but heterogeneous input of new N to nutrient-limited ecosystems at high latitudes. In spite of the broad diversity of mosses found in boreal and Arctic ecosystems, the extent to which host moss identity drives variation in N.sub.2 fixation rates remains largely undetermined. We used .sup.15N.sub.2 incubations to quantify the fixation rates associated with 34 moss species from 24 sites ranging from 60° to 68° N in Alaska, USA. Remarkably, all sampled moss genera fixed N.sub.2, including well-studied feather and peat mosses and genera such as Tomentypnum, Dicranum, and Polytrichum. The total moss-associated N.sub.2 fixation rates ranged from almost zero to 3.2 mg N m.sup.-2 d.sup.-1, with an average of 0.8 mg N m.sup.-2 d.sup.-1, based on abundance-weighted averages of all mosses summed for each site. Random forest models indicated that moss taxonomic family was a better predictor of rate variation across Alaska than any of the measured environmental factors, including site, pH, tree density, and mean annual precipitation and temperature. Consistent with this finding, mixed models showed that trends in N.sub.2 fixation rates among moss genera were consistent across biomes. We also found \"hotspots\" of high fixation rates in one-fourth of sampled sites. Our results demonstrated the importance of moss identity in influencing N.sub.2 fixation rates. This in turn indicates the potential utility of moss identity when making ecosystem N input predictions and exploring other sources of process rate variation.

The leaf economics spectrum[1,2] and the global spectrum of plant forms and functions[3] revealed fundamental axes of variation in plant traits, which represent different ecological strategies that are shaped by the evolutionary development of plant species[2]. Ecosystem functions depend on environmental conditions and the traits of species that comprise the ecological communities[4]. However, the axes of variation of ecosystem functions are largely unknown, which limits our understanding of how ecosystems respond as a whole to anthropogenic drivers, climate and environmental variability[4,5]. Here we derive a set of ecosystem functions[6] from a dataset of surface gas exchange measurements across major terrestrial biomes. We find that most of the variability within ecosystem functions (71.8%) is captured by three key axes. The first axis reflects maximum ecosystem productivity and is mostly explained by vegetation structure. The second axis reflects ecosystem water-use strategies and is jointly explained by variation in vegetation height and climate. The third axis, which represents ecosystem carbon-use efficiency, features a gradient related to aridity, and is explained primarily by variation in vegetation structure. We show that two state-of-the-art land surface models reproduce the first and most important axis of ecosystem functions. However, the models tend to simulate more strongly correlated functions than those observed, which limits their ability to accurately predict the full range of responses to environmental changes in carbon, water and energy cycling in terrestrial ecosystems[7,8]. © 2021. The Author(s).

How the widespread expansion and intensification of aridity through the Neogene has shaped the Austral biota is a major question in Antipodean biogeography.Lineages distributed across wide aridity gradients provide opportunities to examine the timing, frequency, and direction of transitions between arid and mesic regions.Here, we use molecular genetics and morphological data to investigate the systematics and biogeography of a nominal Australian gecko species(Diplodactylus conspicillatus sensu lato) with a wide distribution spanning most of the Australian Arid Zone (AAZ) and Monsoonal Tropics (AMT). Our data support a minimum of seven genetically distinct and morphologically diagnosable taxa; we thus redefine the type species, ressurrect three names from synonymy, and describe three new species. Our inferred phylogeny suggests the history and diversification of lineages in the AAZ and AMT are intimately linked, with evidence of multiple independent interchanges since the late Miocene. However, despite this shared history, related lineages in these two regions also show evidence of broadly contrasting intra-regional responses to aridification; vicarance and speciation in older and increasingly attenuated mesic regions, versus a more dynamic history including independent colonisations and recent range expansions in the younger AAZ.

Terrestrial biosphere models are a key tool in investigating the role played by land surface in the global climate system. However, few models simulate the geographic distribution of biomes dynamically, opting instead to prescribe them using remote sensing products. While prescribing land cover still allows for the simulation of the impacts of climate change on vegetation growth and the impacts of land use change, it prevents the simulation of climate-change-driven biome shifts, with implications for the projection of future terrestrial carbon sink. Here, we isolate the impacts of prescribed vs. dynamic land cover implementations in a terrestrial biosphere model. We first introduce a new framework for evaluating dynamic land cover (i.e., the spatial distribution of plant functional types across the land surface), which can be applied across terrestrial biosphere models alongside standard benchmarking of energy, water, and carbon cycle variables in model intercomparison projects. After validating simulated land cover, we then show that the simulated terrestrial carbon sink differs significantly between simulations with dynamic vs. prescribed land cover for a high-CO.sub.2 future scenario. This is because of important range shifts that are only simulated when dynamic land cover is implemented: tree expansion into the Arctic and Amazonian transition from forest to grassland. In particular, the projected change in net land-atmosphere CO.sub.2 flux at the end of the 21st century is twice as large in simulations with dynamic land cover than in simulations with prescribed land cover. Our results illustrate the importance of climate-change-driven biome shifts for projecting future terrestrial carbon sink.