Dry forest

The ephemeral and fragmented nature of plant communities in the desert region of Ica, Peru have contributed to the poor documentation of its flora. This study provides the first comprehensive checklist and analysis of the vascular plants and habitats of the region, based on over 1800 herbarium collections, site-specific vegetation surveys and monitoring (2001–2017). Here, we report 501 taxa belonging to 283 genera in 68 families, with an outstanding number of taxa (297) representing new records for the region; over 10% of the flora (52 taxa) is categorised as threatened (CR, EN, VU). Asteraceae is the largest family in the checklist, followed by Poaceae, Fabaceae and Solanaceae. The highest species richness is found in quebradas and huaycos (170 taxa), followed by lomas (137 taxa) and huertas (115). Of the lomas taxa, 28% are assessed nationally as threatened, and 95 taxa (68%) are endemic to Peru. Across all habitats five species are restricted to the Ica region (Cleistocactus clavispinus, Haageocereus icensis, Onoseris humboldtiana, Nolana willeana, Tecoma fulva subsp. guarume). Nolana willeana, not collected since 1956, was rediscovered in 2006. We provide insights into habitat and taxonomic delimitation of enigmatic species in the following genera: Bulnesia, Capparis, Eremocharis, Hoffmannseggia, Leptoglossis, Lomanthus Maytenus, Poissonia and Weberbauerella, among others. We support the reinstatement of Prosopis limensis as a valid species and provide information for its identification in the field. Analysis of Inga feuillei as an ancient domestication vital to agriculture, is provided, and we report an additional 127 cultivated species associated with traditional agriculture, assessing origins and conservation priority. We present climatic and geological observations for the region with spatial and ENSOrelated research from data, plots and transects. A vegetation map and niche model are provided. Threatened lomas species are detailed to support conservation and policy. To aid identification we provide photographs of 155 plant species and all key habitats. The sustainable wellbeing of the Ica region depends on concerted collaboration to monitor, conserve and restore native plants wisely for the natural resources they provide to people and agriculture.

The ephemeral and fragmented nature of plant communities in the desert region of Ica, Peru have contributed to the poor documentation of its flora. This study provides the first comprehensive checklist and analysis of the vascular plants and habitats of the region, based on over 1800 herbarium collections, site-specific vegetation surveys and monitoring (2001–2017). Here, we report 501 taxa belonging to 283 genera in 68 families, with an outstanding number of taxa (297) representing new records for the region; over 10% of the flora (52 taxa) is categorised as threatened (CR, EN, VU). Asteraceae is the largest family in the checklist, followed by Poaceae, Fabaceae and Solanaceae. The highest species richness is found in quebradas and huaycos (170 taxa), followed by lomas (137 taxa) and huertas (115). Of the lomas taxa, 28% are assessed nationally as threatened, and 95 taxa (68%) are endemic to Peru. Across all habitats five species are restricted to the Ica region (Cleistocactus clav...

Aim This study aims to improve the formulation and results of the Brazilian Center for Weather Forecasting and Climate Studies Potential Vegetation Model (CPTEC-PVM) by developing a new parameterization for the long-term occurrence of fire in regions of potential savannas in the tropics. Compared with the relatively slow processes of carbon uptake and growth in vegetation, fast mortality and biomass consumption by fires may favour grasses and reduce tree coverage. Location The tropics. Methods For finding large-scale relationships between fires and other environmental factors, we made two main simplifying assumptions. First, lightning is the most important source of ignition for natural fires. Second, over continental areas in the tropics, lightning is mainly related to the zonal flux of moisture transport. Results The parameterization of fire occurrence was built based on a simple empirical relationship, combining information on mean and intra-annual variance of the zonal wind. Main conclusions The implementation of this new relationship improved the formulation and the results of the CPTEC-PVM. As a result of this new parameter, the accuracy of the model in allocating the correct vegetation (seasonal forests) instead of savannas for large regions in India and Southeast Asia is now substantially higher than in previous studies.

The genetic diversity of Myrciaria floribunda, a common Atlantic Forest tree, was investigated in six populations located in two small fragments (10 and 18 ha), two medium-sized fragments (36 and 44 ha) and one large fragment (3003 ha). Two populations occur in the large fragment. It is expected that smaller fragments should have lower genetic diversity and higher inbreeding. Distances between fragments varied from 0.66 to 10 km. On average 32 young trees smaller than 20 cm basal girth were sampled in each population. Allozyme electrophoresis was carried out, and six loci were scored. The effective number of alleles was lower for populations of the two small fragments (1.46 and 1.51) and higher for populations of the large (1.62 and 1.71) and medium ones (1.69 and 1.84). Small fragments showed lower values of expected and observed heterozygosities than large and medium fragments. Most of the genetic variability occurs within populations, and there was a moderate genetic variation am...

Accurate differentiation between tropical forest and savannah ecosystems in the fossil pollen record is hampered by the combination of: i) poor taxonomic resolution in pollen identification, and ii) the high species diversity of many lowland tropical families, i.e. with many different growth forms living in numerous environmental settings. These barriers to interpreting the fossil record hinder our understanding of the past distributions of different Neotropical ecosystems and consequently cloud our knowledge of past climatic, biodiversity and carbon storage patterns. Modern pollen studies facilitate an improved understanding of how ecosystems are represented by the pollen their plants produce and therefore aid interpretation of fossil pollen records. To understand how to differentiate ecosystems palynologically, it is essential that a consistent sampling method is used across ecosystems. However, to date, modern pollen studies from tropical South America have employed a variety of methodologies (e.g. pollen traps, moss polsters, soil samples). In this paper, we present the first modern pollen study from the Neotropics to examine the modern pollen rain from moist evergreen tropical forest (METF), semi-deciduous dry tropical forest (SDTF) and wooded savannah (cerradão) using a consistent sampling methodology (pollen traps). Pollen rain was sampled annually in September for the years 1999-2001 from within permanent vegetation study plots in, or near, the Noel Kempff Mercado National Park (NKMNP), Bolivia. Comparison of the modern pollen rain within these plots with detailed floristic inventories allowed estimates of the relative pollen productivity and dispersal for individual taxa to be made (% pollen / % vegetation or ‘p/v’). The applicability of these data to interpreting fossil records from lake sediments was then explored by comparison with pollen assemblages obtained from five lake surface samples.
Pollen productivity is demonstrated to vary inter-annually and conforms to a consistent hierarchy for any given year: METF > SDTF > cerradão. This suggests an association between pollen productivity and basic structural characteristics of the ecosystem, i.e. closed canopy vs. open canopy vs. savannah. Comparison of modern pollen and vegetation revealed that some important floristic elements were completely absent from the pollen: Qualea and Erisma (METF), Bauhinia, Simira and Guazuma (SDTF), and Pouteria and Caryocar (cerradão). Anadenanthera was found to be abundant in both the pollen and flora of SDTF (p/v = 3.6), while Poaceae was relatively poorly represented in cerradão (0.2). Moraceae, Cecropia and Schefflera were found to be over-represented palynologically in all ecosystems. Overall, the data demonstrated that no one taxon could be used as a definitive indicator of any of the ecosystems. Instead, associations of taxa were found to be important: METF = Moraceae (>40%), Cecropia, Hyeronima, Celtis; SDTF = Anadenanthera, Apuleia, Ferdinandusa and non-arboreal Asteraceae, Bromeliaceae, Piper and fern spores; cerradão = Poaceae, Myrtaceae, Borreria, Solanum plus Asteraceae and fern spores. Interpretation of Poaceae pollen was highlighted as problematic, with relatively low abundance in the cerradão (<20%) in comparison to high abundance in lake environments (c. 30-50%). Re-examination of fossil pollen records from NKMNP revealed that modern vegetation associations were only established in the last few thousand years.

Aim of study: To compare litter decomposition dynamics among different species within a single forest type and also between a single species in different forest successional stages.Area of study: Different forests of a known successional sequence of the Mesopotamian Espinal, placed in Villaguay Department, Entre Ríos Province, Argentina.Material and methods: A standard “litter bags” technique was employed. Chemical analyses of C and N were performed for leaves. A regression analysis was applied and data were fitted to a double exponential model. Means estimated among forests and species within each forest were compared using the Tukey-Kramer test.Main results: The model predicted that leaves would completely mineralize in the mid-term. Leaf decomposition rate in different species (both in the Secondary forest and Mature forest) had dry matter residues in the following decreasing order: Acacia caven &gt; Prosopis nigra &gt; Prosopis affinis &gt; Celtis ehrenbergiana. Research highlig...

sponding author. Hailstorm impact across plant taxa: Leaf fall in a mountain environment Impacto de uma tempestade de granizo em diferentes táxons vegetais: queda foliar em um ambiente de montanha Natural catastrophes in the planet increased over 400 % from 1970 to 2005, causing seve-re impact on natural ecosystems, and are sought to increase in the forthcoming decades due to climate change driven events. However, the descriptions of the impacts caused by events as hailstorms on wild ecosystems are anecdotal in the tropical region. The oc-currence of a severe hailstorm on a mountainous tropical environment in Brazil allowed, for the first time, to examine hailstorm impact on 32 plant species belonging to distinct families. The study was carried out in an area of rupestrian field located in Serra do Cipó, Minas Gerais State, Brazil. The impact of hail on the vegetation was evaluated by an index of damage and the damage level was related to plant species architectural features. Hail