Re-creation of heathland on improved pasture using topsoil removal and sulphur amendments: edaphic drivers and impacts on ericoid mycorrhizas

Understanding the factors that drive successful re-creation and restoration of lowland heaths is crucially important for achieving the long-term conservation of this threatened habitat type. In this study we investigated the changes in soil chemistry, plant community and interactions between Calluna vulgaris and symbiotic ericoid mycorrhizas (ERM) that occurred when improved pasture was subjected to one of three treatments (i) acidification with elemental sulphur (ii) acidification with ferrous sulphur (iii) removal of the topsoil. We found that the soil stripping treatment produced the greatest reduction in available phosphate but did not decrease soil pH. Conversely, acidification with elemental sulphur decreased pH but increased availability of phosphate and potentially toxic cations. The elemental sulphur treatment produced plant communities that most closely resembled those on surrounding heaths and acid grasslands. The most important driver was low pH and concomitant increased availability of potentially toxic cations. Plant community development was found to be little related to levels of available soil phosphate, particularly at low pH. The elemental sulphur treatment also produced the best germination and growth of C. vulgaris over 4���5 years. However, this treatment was found to inhibit the development of symbiotic relationships between C. vulgaris and ERM. This may affect the long-term persistence of re-created vegetation and its interactions with other components of heathland communities.

Are sulfurous soil amendments (S0, Fe(II)SO4, Fe(III)SO4) an effective tool in the restoration of heathland and acidic grassland after four decades of rock phosphate Fertilization?

This paper deals with the complex issue of reversing long-term improvements of fertility in soils derived from heathlands and acidic grasslands using sulfur-based amendments. The experiment was conducted on a former heathland and acid grassland in the U.K. that was heavily fertilized and limed with rock phosphate, chalk, and marl. The experimental work had three aims. First, to determine whether sulfurous soil amendments are able to lower pH to a level suitable for heathland and acidic grassland re-creation (approximately 3 pH units). Second, to determine what effect the soil amendments have on the available pool of some basic cations and some potentially toxic acidic cations that may affect the plant community. Third, to determine whether the addition of Fe to the soil system would sequester PO4��� ions that might be liberated from rock phosphate by the experimental treatments. The application of S0 and Fe(II)SO4��� to the soil was able to reduce pH. However, only the highest S0 treatment (2,000 kg/ha S) lowered pH sufficiently for heathland restoration purposes but effectively so. Where pH was lowered, basic cations were lost from the exchangeable pool and replaced by acidic cations. Where Fe was added to the soil, there was no evidence of PO4��� sequestration from soil test data (Olsen P), but sequestration was apparent because of lower foliar P in the grass sward. The ability of the forb Rumex acetosella to apparently detoxify Al3+, prevalent in acidified soils, appeared to give it a competitive advantage over other less tolerant species. We would anticipate further changes in plant community structure through time, driven by Al3+ toxicity, leading to the competitive exclusion of less tolerant species. This, we suggest, is a key abiotic driver in the restoration of biotic (acidic plant) communities.

Green infrastructure and ecosystem services - is the devil in the detail?

Background - Green infrastructure is a strategic network of green spaces designed to deliver ecosystem services to human communities. Green infrastructure is a convenient concept for urban policy makers, but the term is used too-generically and with limited understanding of the relative values or benefits of different types of green space and how these complement one another. At a finer scale/more practical level��� little consideration is given to the composition of the plant-communities, yet this is what ultimately defines extent of service provision. This paper calls for greater attention to be paid to urban plantings with respect to ecosystem service delivery and for plant science to engage more-fully in identifying those plants that promote various services. Scope - Many urban plantings are designed based on aesthetics alone, with limited thought on how plant choice/composition provides other ecosystem services. Research is beginning to demonstrate, however, that landscape plants provide a range of important services, such as helping mitigate floods and alleviating heat islands, but that not all species are equally effective. The paper reviews a number of important services and demonstrates how genotype choice radically affects service delivery. Conclusions ��� Although research is in its infancy, data is being generated that relates plant traits to specific services; thereby helping identify genotypes that optimise service delivery. The urban environment, however, will become exceedingly bland if future planting is simply restricted to monocultures of a few ���functional��� genotypes. Therefore, further information is required on how to design plant communities where the plants identified:- a/ provide more than a single benefit (multi-functionality) b/ complement each other in maximising the range of benefits that can be delivered in one location and c/ continue to maintain public acceptance through diversity. The identification/development of functional landscape plants is an exciting and potentially high impact arena for plant science.

Successional stage and geographic features determine floristic similarity among Atlantic Forest remnants, Sao Paulo State, Brazil

Analysis of floristic similarity relationships between plant communities can detect patterns of species occurrence and also explain conditioning factors. Searching for such patterns, floristic similarity relationships among Atlantic Forest sites situated at Ibiuna Plateau, Sao Paulo state, Brazil, were analyzed by multivariate techniques. Twenty one forest fragments and six sites within a continuous Forest Reserve were included in the analyses. Floristic composition and structure of the tree community (minimum dbh 5 cm) were assessed using the point centered quarter method. Two methods were used for multivariate analysis: Detrended Correspondence Analysis (DCA) and Two-Way Indicator Species Analysis (TWINSPAN). Similarity relationships among the study areas were based on the successional stage of the community and also on spatial proximity. The more similar the successional stage of the communities, the higher the floristic similarity between them, especially if the communities are geographically close. A floristic gradient from north to south was observed, suggesting a transition between biomes, since northern indicator species are mostly heliophytes, occurring also in cerrado vegetation and seasonal semideciduous forest, while southern indicator species are mostly typical ombrophilous and climax species from typical dense evergreen Atlantic Forest.

Processos de degrada����o e regenera����o da vegeta����o campestre do entorno de areais do sudoeste do Rio Grande do Sul

No Sudoeste do Rio Grande do Sul ocorrem manchas de substrato arenoso sem cobertura vegetal, conhecidos regionalmente como areais. A tese reexamina o problema e suas causas, enfatizando o papel da vegeta����o natural e propondo estrat��gias para a revegeta����o e preven����o �� areniza����o em sistemas pastoris. Evid��ncias foram obtidas em levantamentos e experimento avaliando processos de degrada����o e regenera����o da vegeta����o campestre do entorno de areais. Levantamento da vegeta����o, realizado em 41 parcelas de 4,5 x 9,0 m na borda de 11 areais indicou a exist��ncia de dois tipos de comunidades. Areais de Manoel Viana e aqueles usados pelo gado em S��o Francisco de Assis, com alto percentual de substrato exposto, s��o caracterizados principalmente por Elyonurus sp., Axonopus pressus e Butia paraguayensis. Areais de Alegrete e aqueles exclu��dos de pastejo em S��o Francisco de Assis, com menor percentual de substrato exposto, s��o caracterizados principalmente por Andropogon lateralis e Aristida laevis. Foi tamb��m avaliada a din��mica da vegeta����o em gradientes de areniza����o, usando quadros (0,25 m2) cont��guos em 16 transec����es de 10 m localizadas em cinco areais. A din��mica da vegeta����o foi associada ao uso das ��reas pelo gado, pois houve aumento, ap��s 14 meses, de substrato exposto em comunidades de areais sob pastoreio, enquanto que aquelas sem gado apresentaram uma din��mica espacial-temporal de maior estabilidade da cobertura vegetal. Um experimento foi realizado para avaliar, durante 8 meses, o efeito de n��veis controlados de soterramento por areia (0, 5, 10 e 20 cm) em comunidades do entorno de dois areais sob pastoreio. Comunidades caracterizadas por Elyonurus sp. e Axonopus pressus foram mais tolerantes ao soterramento. As evid��ncias indicam que a exclus��o do gado de areais pode ser uma alternativa eficaz para a revegeta����o de areais por esp��cies das comunidades naturais do entorno. Ademais, a areniza����o pode ser prevenida pelo uso adequado dos campos que mantenha a cobertura vegetal natural protegendo o solo dos processos erosivos h��drico e e��lico.

Bacterial functional redundancy along a soil reclamation gradient

A strategy to measure bacterial functional redundancy was developed and tested with soils collected along a soil reclamation gradient by determining the richness and diversity of bacterial groups capable of in situ growth on selected carbon substrates. Soil cores were collected from four sites along a transect from the Jamari tin mine site in the Jamari National Forest, Rondonia, RO, Brazil: denuded mine spoil, soil from below the canopy of invading pioneer trees, revegetated soil under new growth on the forest edge, and the forest floor of an adjacent preserved forest. Bacterial population responses were analyzed by amending these soil samples with individual carbon substrates in the presence of bromodeoxyuridine (BrdU), BrdU-labeled DNA was then subjected to a 16S-23S rRNA intergenic analysis to depict the actively growing bacteria from each site, the number and diversity of bacterial groups responding to four carbon substrates (L-serine, L-threonine, sodium citrate, and or-lactose hydrate) increased along the reclamation-vegetation gradient such that the preserved forest soil samples contained the highest functional redundancy for each substrate. These data suggest that bacterial functional redundancy increases in relation to the regrowth of plant communities and may therefore represent an important aspect of the restoration of soil biological functionality to reclaimed mine spoils. They also suggest that bacterial functional redundancy may be a useful indicator of soil quality and ecosystem functioning.

Ocorr��ncia de plantas aqu��ticas nos reservat��rios da Companhia Energ��tica de S��o Paulo

O objetivo do presente trabalho foi caracterizar as comunidades de plantas aqu��ticas presentes nos reservat��rios da Companhia Energ��tica de S��o Paulo. Os levantamentos foram realizados entre janeiro e dezembro de 1999, percorrendo-se com um barco as margens dos reservat��rios de Tr��s Irm��os, Jupi��, Ilha Solteira, Porto Primavera, Paraibuna e Jaguari, visando identificar as ��reas com infesta����es de plantas aqu��ticas. em cada ponto de avalia����o, fez-se a identifica����o das esp��cies e estimou-se visualmente a ��rea total infestada e a participa����o de cada esp��cie (em % da ��rea total). Com as informa����es coletadas em campo, procedeu-se a uma etapa de trabalhos em escrit��rio, incluindo a identifica����o das esp��cies de plantas aqu��ticas nos casos em que n��o era poss��vel identificar as esp��cies no local; a determina����o de classes de plantas aqu��ticas (emersas, emersas com folhas flutuantes, submersas, flutuantes); a identifica����o das esp��cies mais freq��entes; e o estabelecimento de rela����es de domin��ncia e co-domin��ncia. S��o apresentados os resultados obtidos em cada reservat��rio.

Din��mica sazional de fungos micorr��zicos arbusculares (Glomeromycota) em cerrad��o e brejo de altitude na Chapada do Araripe, CE

Arbuscular mycorrhizal fungi (AMF) are obligatory symbiotic organisms that associate with roots of a large number of plant taxa, and are found in all terrestrial ecosystems. These fungi promote greater tolerance to environmental stresses to associated plant, favoring the establishment of plant communities, especially where soil fertility is a limiting factor, as in the Caatinga, an exclusively Brazilian domain that has been focus of research due to its great biodiversity that can help clarify the history of vegetation in South America. Because of the ecological importance of AMF, the limited number of jobs and the potential diversity of the Caatinga, this work aims to inventory the diversity and determine AMF communities in areas with different faces occurrent in FLONA Araripe, Cear�� (CE). The sample collection occurred in four periods at the beginning and end of the dry season (August and December 2011, respectively) and rainy (February and June 2012, respectively) in an area of marsh and woodland altitude of the Araripe, Crato, CE. The glomerosporos were extracted by wet sieving and centrifugation in water and sucrose (50%) mounted between slide and coverslip using PVLG and PVLG + Reagent Melzer. In total, we found 46 species of AMF distributed in eight families and 16 genera: Acaulospora (6), Ambispora (1), Cetraspora (2), Dentiscutata (5), Fuscutata (2), Gigaspora (6), Glomus (13) Intraornatospora (1), Kuklospora (1), Orbispora (1), Paradentiscutata (1), Quatunica (1), Racocetra (1), Scutellospora (2), Septoglomus (2) and a new genus. analysis showed that ecological each area of study has its own seasonal dynamics, with an area of woodland with a greater diversity of species throughout the year, while the marsh elevation showed greater variation in species found among the collection periods, showing that vegetation and rainfall has strong influence on the seasonal dynamics of AMF, as well as the availability of nutrients and soil pH so

The use of biodiversity as source of new chemical entities against defined molecular targets for treatment of malaria, tuberculosis, and T-cell mediated diseases: a review

The modern approach to the development of new chemical entities against complex diseases, especially the neglected endemic diseases such as tuberculosis and malaria, is based on the use of defined molecular targets. Among the advantages, this approach allows (i) the search and identification of lead compounds with defined molecular mechanisms against a defined target (e.g. enzymes from defined pathways), (ii) the analysis of a great number of compounds with a favorable cost/benefit ratio, (iii) the development even in the initial stages of compounds with selective toxicity (the fundamental principle of chemotherapy), (iv) the evaluation of plant extracts as well as of pure substances. The current use of such technology, unfortunately, is concentrated in developed countries, especially in the big pharma. This fact contributes in a significant way to hamper the development of innovative new compounds to treat neglected diseases. The large biodiversity within the territory of Brazil puts the country in a strategic position to develop the rational and sustained exploration of new metabolites of therapeutic value. The extension of the country covers a wide range of climates, soil types, and altitudes, providing a unique set of selective pressures for the adaptation of plant life in these scenarios. Chemical diversity is also driven by these forces, in an attempt to best fit the plant communities to the particular abiotic stresses, fauna, and microbes that co-exist with them. Certain areas of vegetation (Amazonian Forest, Atlantic Forest, Araucaria Forest, Cerrado-Brazilian Savanna, and Caatinga) are rich in species and types of environments to be used to search for natural compounds active against tuberculosis, malaria, and chronic-degenerative diseases. The present review describes some strategies to search for natural compounds, whose choice can be based on ethnobotanical and chemotaxonomical studies, and screen for their ability to bind to immobilized drug targets and to inhibit their activities. Molecular cloning, gene knockout, protein expression and purification, N-terminal sequencing, and mass spectrometry are the methods of choice to provide homogeneous drug targets for immobilization by optimized chemical reactions. Plant extract preparations, fractionation of promising plant extracts, propagation protocols and definition of in planta studies to maximize product yield of plant species producing active compounds have to be performed to provide a continuing supply of bioactive materials. Chemical characterization of natural compounds, determination of mode of action by kinetics and other spectroscopic methods (MS, X-ray, NMR), as well as in vitro and in vivo biological assays, chemical derivatization, and structure-activity relationships have to be carried out to provide a thorough knowledge on which to base the search for natural compounds or their derivatives with biological activity.

Flor��stica de uma Floresta Estacional Semidecidual, localizada em ec��tono sav��nico-florestal, no munic��pio de Bauru, SP, Brasil

Informa����es flor��sticas escassas, referentes ao munic��pio de Bauru, e a elabora����o de hip��teses sobre mecanismos de ocupa����o de fitocenoses florestais por esp��cies sav��nicas, representaram as principais quest��es motivadoras do presente estudo, desenvolvido em dois fragmentos de floresta estacional semidecidual (5 ha e 7 ha) mantidos pelo Jardim Bot��nico de Bauru, que abriga tamb��m savana florestada. O material bot��nico foi coletado a partir de caminhadas ao acaso e em parcelas implantadas durante estudo fitossociol��gico. Foram encontradas 264 esp��cies arbustivo-arb��reas, pertencentes a 58 fam��lias. Dessas esp��cies 126 foram coletadas apenas na fitocenose florestal, e 66 esp��cies foram coletadas em ambas as fitocenoses. As duas fam��lias com o maior n��mero de esp��cies foram Rubiaceae (25 esp��cies) e Myrtaceae (21 esp��cies). Foi realizada an��lise de similaridade flor��stica, a partir do ��ndice de Jaccard (SJ), entre a floresta do JBMB e outros 11 remanescentes florestais, alguns dos quais, sob influ��ncia flor��stica sav��nica. A riqueza flor��stica dos fragmentos florestais do JBMB sofreu incremento, pela ocupa����o de esp��cies sav��nicas, oriundas da savana florestada cont��gua. Inc��ndios pret��ritos, al��m da ocorr��ncia de microambientes distintos, representaram prov��veis fatores de facilita����o para a invas��o dessas esp��cies sav��nicas.

Storage in cerrado soil and germination of Psychotria vellosiana (Rubiaceae) seeds

The regeneration of plant communities from seed depends, to a large extent, on the capacity of the seed remaining viable in the soil. The viability and germination of artificially buried Psychotria vellosiana seeds in cerrado soil were studied, with the purpose of discovering some physio-ecological aspects of dispersed seeds and evaluating their potential to constitute a soil seed bank. Seed samples were placed in nylon envelopes and buried in the soil of a Cerrado reserve at two different depths and sites. Buried seeds were retrieved periodically and tested for germination along with dry-stored seeds. In general, there was a reduction in seed germination with storage time, both in soil and dry stored conditions, and in some assays exhumed seeds germinated faster than dry stored ones. In general the soil storage favoured seed viability of ungerminated seeds as compared to dry stored ones, with the seeds remaining partially viable after 10 months of storage. The lack of germination of viable seeds suggests that seeds showed true dormancy and/or required an extended time to germinate. It was observed that some seeds had germinated while buried and such in situ germination tended to increase with rainfall. The water availability in the soil might be a limiting factor for successful germination of P. vellosiana in the field, and the seeds may constitute a persistent soil seed bank in the cerrado as dispersed seeds remain viable in the soil until the following period of seed dispersal.

No changes in seedling recruitment when terrestrial mammals are excluded in a partially defaunated Atlantic rainforest

One of the most intriguing questions in ecology is how to identify which and how many species will be able to inhabit human-modified landscapes. Large-bodied mammals structure plant communities by trampling, herbivory, seed dispersal and predation, and their local extinction may have pervasive consequences in plant communities due to the breakdown of key interactions. Although much attention has been given to understanding the effects of defaunation on plant communities, information on the potential impacts on plant functional groups (seed dispersal, seed size and seedling leaves defense) inhabiting continuous forests after defaunation is scarce. We conducted mammal surveys (line transects and camera trapping) to determine the defaunation status of a continuous Atlantic forest in Brazil. Then, we evaluated the effects of defaunation on seedling diversity, richness and abundance of functional groups using 15 plot-pairs (each pair with one open and one exclusion plot) monitored over 36. months. We found that the studied area is partially defaunated because it exhibits high abundance of primates, while terrestrial mammals, such as large rodents and ungulates, are rare. We found no significant changes in either seedling richness and diversity or in the seedling composition of plant functional groups in response to mammal exclosure. Seedling mortality and recruitment were similar between plot types. Our findings suggest that at semi-defaunated areas, where arboreal species are still present, terrestrial mammals have low impacts on the plant community reassembly. �� 2013 Elsevier Ltd.

Engenheiros dos ecossistemas em plantas: modifica����es arquiteturais de folhas por largatas de Lepidoptera influenciam a estrutura de comunidades de artr��podes

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

��caros associados a plantas da regi��o Core do Cerrado e sua influ��ncia na acarofauna em cultivos de soja (Glycine max (L.) Merril) (Fabaceae)

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

An��lise morfom��trica e biodiversidade da vegeta����o na microbacia hidrogr��fica da Fazenda Experimental Edg��rdia

Conselho Nacional de Desenvolvimento Cient��fico e Tecnol��gico (CNPq)