Influence of land use changes in river basins on diversity and distribution of amphibians

Land-use changes influence local biodiversity directly, and also cumulatively, contribute to regional and global changes in natural systems and quality of life. Consequent to these, direct impacts on the natural resources that support the health and integrity of living beings are evident in recent times. The Western Ghats being one of the global biodiversity hotspots, is reeling under a tremendous pressure from human induced changes in terms of developmental projects like hydel or thermal power plants, big dams, mining activities, unplanned agricultural practices,monoculture plantations, illegal timber logging, etc. This has led to the once contiguous forest habitats to be fragmented in patches, which in turn has led to the shrinkage of original habitat for the wildlife, change in the hydrological regime of the catchment, decreased inflow in streams,human-animal conflicts, etc. Under such circumstances, a proper management practice is called for requiring suitable biological indicators to show the impact of these changes, set priority regions and in developing models for conservation planning. Amphibians are regarded as one of the best biological indicators due to their sensitivity to even the slightest changes in the environment and hence they could be used as surrogates in conservation and management practices. They are the predominating vertebrates with a high degree of endemism (78%) in Western Ghats. The present study is an attempt to bring in the impacts of various land-uses on anuran distribution in three river basins. Sampling was carried out for amphibians during all seasons of 2003-2006 in basins of Sharavathi, Aghanashini and Bedthi. There are as many as 46 species in the region, one of which is new to science and nearly 59% of them are endemic to the Western Ghats. They belong to nine families, Dicroglossidae being represented by 14 species,followed by Rhacophoridae (9 species) and Ranidae (5 species). Species richness is high in Sharavathi river basin, with 36 species, followed by Bedthi 33 and Aghanashini 27. The impact of land-use changes, was investigated in the upper catchment of Sharavathi river basin. Species diversity indices, relative abundance values, percentage endemics gave clear indication of differences in each sub-catchment. Karl Pearson���s correlation coefficient (r) was calculated between species richness, endemics, environmental descriptors, land-use classes and fragmentation metrics. Principal component analysis was performed to depict the influence of these variables. Results show that sub-catchments with lesser percentage of forest, low canopy cover, higher amount of agricultural area, low rainfall have low species richness, less endemic species and abundant non-endemic species, whereas endemism, species richness and abundance of endemic species are more in the sub-catchments with high tree density, endemic trees, canopy cover, rainfall and lower amount of agriculture fields. This analysis aided in prioritising regions in the Sharavathi river basin for further conservation measures.

An��lise das mudan��as na extens��o do gelo marinho ant��rtico e ��rtico entre 1979 e 2007 e sua rela����o com a variabilidade clim��tica global.

Recentes observa����es satelitais t��m demonstrado um aumento na extens��o total do gelo marinho Ant��rtico e redu����o do gelo marinho no ��rtico. Apesar destas constata����es, no Oceano Sul an��lises regionais apontam tend��ncias negativas nos mares de Bellingshausen-Amundsen e positivas no mar de Ross, enquanto que para o ��rtico ocorrer uma redu����o uniforme do gelo marinho. Neste estudo, foi realizada uma an��lise multivariada para identificar as mudan��as na extens��o do gelo marinho Ant��rtico e ��rtico em resposta �� variabilidade de um conjunto de for��antes/par��metros/��ndices clim��ticos de reconhecida import��ncia em escala global. Especificamente, as associa����es entre o gelo marinho e os par��metros e for��antes clim��ticos foram examinadas atrav��s da correla����o linear e da an��lise de agrupamento. Diferentes respostas em diferentes setores foram examinadas e discutidas. Os resultados indicam que a variabilidade do gelo marinho Ant��rtico e ��rtico �� um fen��meno multivariado e que a extens��o de gelo marinho m��nima, m��dia e m��xima podem apresentar diferentes padr��es espaciais e responderem a diferentes conjuntos de par��metros e for��antes clim��ticos. Foi identificado um significativo impacto de for��antes/par��metros/��ndices clim��ticos sobre o gelo marinho no Oeste Ant��rtico. No hemisf��rio Norte o aumento da temperatura m��dia global e do CO2 atmosf��rico s��o os principais respons��veis pela redu����o na extens��o do gelo marinho.

The potential consequences of climate variability and change on coastal areas and marine resources: report of the Coastal Areas and Marine Resources Sector Team, U.S. National Assessment of the Potential Consequences of Climate Variability and Change, U.S. Global Change Research Program

Coastal and marine ecosystems support diverse and important fisheries throughout the nation���s waters, hold vast storehouses of biological diversity, and provide unparalleled recreational opportunities. Some 53% of the total U.S. population live on the 17% of land in the coastal zone, and these areas become more crowded every year. Demands on coastal and marine resources are rapidly increasing, and as coastal areas become more developed, the vulnerability of human settlements to hurricanes, storm surges, and flooding events also increases. Coastal and marine environments are intrinsically linked to climate in many ways. The ocean is an important distributor of the planet���s heat, and this distribution could be strongly influenced by changes in global climate over the 21st century. Sea-level rise is projected to accelerate during the 21st century, with dramatic impacts in low-lying regions where subsidence and erosion problems already exist. Many other impacts of climate change on the oceans are difficult to project, such as the effects on ocean temperatures and precipitation patterns, although the potential consequences of various changes can be assessed to a degree. In other instances, research is demonstrating that global changes may already be significantly impacting marine ecosystems, such as the impact of increasing nitrogen on coastal waters and the direct effect of increasing carbon dioxide on coral reefs. Coastal erosion is already a widespread problem in much of the country and has significant impacts on undeveloped shorelines as well as on coastal development and infrastructure. Along the Pacific Coast, cycles of beach and cliff erosion have been linked to El Ni��o events that elevate average sea levels over the short term and alter storm tracks that affect erosion and wave damage along the coastline. These impacts will be exacerbated by long-term sea-level rise. Atlantic and Gulf coastlines are especially vulnerable to long-term sea-level rise as well as any increase in the frequency of storm surges or hurricanes. Most erosion events here are the result of storms and extreme events, and the slope of these areas is so gentle that a small rise in sea level produces a large inland shift of the shoreline. When buildings, roads and seawalls block this natural migration, the beaches and shorelines erode, threatening property and infrastructure as well as coastal ecosystems.

Exploiting satellite earth observation to quantify current global oceanic DMS flux and its future climate sensitivity

We used coincident Envisat RA2 and AATSR temperature and wind speed data from 2008/2009 to calculate the global net sea-air flux of dimethyl sulfide (DMS), which we estimate to be 19.6 Tg S a21. Our monthly flux calculations are compared to open ocean eddy correlation measurements of DMS flux from 10 recent cruises, with a root mean square difference of 3.1 lmol m22 day21. In a sensitivity analysis, we varied temperature, salinity, surface wind speed, and aqueous DMS concentration, using fixed global changes as well as CMIP5 model output. The range of DMS flux in future climate scenarios is discussed. The CMIP5 model predicts a reduction in surface wind speed and we estimate that this will decrease the global annual sea-air flux of DMS by 22% over 25 years. Concurrent changes in temperature, salinity, and DMS concentration increase the global flux by much smaller amounts. The net effect of all CMIP5 modelled 25 year predictions was a 19% reduction in global DMS flux. 25 year DMS concentration changes had significant regional effects, some positive (Southern Ocean, North Atlantic, Northwest Pacific) and some negative (isolated regions along the Equator and in the Indian Ocean). Using satellite-detected coverage of coccolithophore blooms, our estimate of their contribution to North Atlantic DMS emissions suggests that the coccolithophores contribute only a small percentage of the North Atlantic annual flux estimate, but may be more important in the summertime and in the northeast Atlantic.

Salinity changes in the world ocean since 1950 in relation to changing surface freshwater fluxes

Global hydrographic and air���sea freshwater flux datasets are used to investigate ocean salinity changes over 1950���2010 in relation to surface freshwater flux. On multi-decadal timescales, surface salinity increases (decreases) in evaporation (precipitation) dominated regions, the Atlantic���Pacific salinity contrast increases, and the upper thermocline salinity maximum increases while the salinity minimum of intermediate waters decreases. Potential trends in E���P are examined for 1950���2010 (using two reanalyses) and 1979���2010 (using four reanalyses and two blended products). Large differences in the 1950���2010 E���P trend patterns are evident in several regions, particularly the North Atlantic. For 1979���2010 some coherency in the spatial change patterns is evident but there is still a large spread in trend magnitude and sign between the six E���P products. However, a robust pattern of increased E���P in the southern hemisphere subtropical gyres is seen in all products. There is also some evidence in the tropical Pacific for a link between the spatial change patterns of salinity and E���P associated with ENSO. The water cycle amplification rate over specific regions is subsequently inferred from the observed 3-D salinity change field using a salt conservation equation in variable isopycnal volumes, implicitly accounting for the migration of isopycnal surfaces. Inferred global changes of E���P over 1950���2010 amount to an increase of 1 �� 0.6 % in net evaporation across the subtropics and an increase of 4.2 �� 2 % in net precipitation across subpolar latitudes. Amplification rates are approximately doubled over 1979���2010, consistent with accelerated broad-scale warming but also coincident with much improved salinity sampling over the latter period.

Related changes in biodiversity, insolation and climate in the Atlantic rainforest since the last interglacial

The long-term Colonia record is located in the Atlantic rainforest domain in Brazil (23 degrees 52`S 46 degrees 42`20 `` W 900 m a.s.l.). The 780 cm long core CO3 provides a coverage of a complete interglacial/glacial cycle for the first time in a neotropical rainforest. Information on the behavior of tropical climates compared to global changes in temperatures indicates specific climate responses in terms of precipitation at these latitudes. Winter extratropical circulation was very active during the last interglacial and most of the glacial. Floristic composition of the rainforest changed several times in each phase of expansion, twice during the interglacial, and three times during glacial episodes. Araucaria was well developed in the area of Sao Paulo until the beginning of the first dry phase of the glacial at ca. 50,000 yr B.P. Changes in insolation controlled the expansion of the rainforest and the tropical hydrological cycle as evidenced by a strong precession signal. However precession had no impact on regional climatic features. The two interglacials (MIS 5e and Holocene) showed completely different patterns attesting to the continuous evolution of the forest. The biodiversity index (Shannon-Wiener Index) remained high during both the interglacial and glacial attesting to the permanence of small patches of rainforest refugia during drier phases. The lowest Shannon-Wiener Indexes were recorded between 23,000 and 12,000 yr B.P. and 40,000 and 30,000 yr B.P. and characterize two marked phases of stress for the rainforest. (C) 2008 Elsevier B.V. All rights reserved.

Global change and health - the good, the bad, and the evidence

Debates over the merits and demerits of globalisation for health are increasingly polarised. Conclusions range from globalisation being essentially positive for health, albeit with a need to smooth out some rough edges, to one of utter condemnation, with adverse effects on the majority of the world's population. Anyone wading into this debate is immediately confronted by seemingly irreconcilable differences in ideology, opinion and interests. Both camps agree that global changes are occurring, and with them many of the determinants of population health status. While some skepticism persists about whether &ldquo;globalisation&rdquo; has value beyond being a fashionable buzzword, most agree that we need better understanding of these changes. Two difficult questions arise: (i) What are the health impacts of these changes; and (ii) how can we respond more effectively to them? To move beyond the stand-offs that have already formed within the health community, this paper reviews the main empirical evidence that currently exists, summarises key points of debate that remain, and suggests some ways forward for the research and policy communities. In particular, there is need for an informed and inclusive debate about the positive and negative health consequences of globalisation.<br />

An��lise da express��o g��nica global da bact��ria Xylella fastidiosa em laranja doce por microarranjos de DNA

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Ice core-based isotopic constraints on past carbon cycle changes

High-precision ice core data on both atmospheric CO2 concentrations and their carbon isotopic composition (��13Catm) provide improved constraints on the marine and terrestrial processes responsible for carbon cycle changes during the last two interglacials and the preceding glacial/interglacial transitions.

Coral-algae metabolism and diurnal changes in the CO2-carbonate system of bulk sea water

Precise measurements were conducted in continuous flow seawater mesocosms located in full sunlight that compared metabolic response of coral, coral-macroalgae and macroalgae systems over a diurnal cycle. Irradiance controlled net photosynthesis (Pnet), which in turn drove net calcification (Gnet), and altered pH. Pnet exerted the dominant control on [CO3]2- and aragonite saturation state (Omega arag) over the diel cycle. Dark calcification rate decreased after sunset, reaching zero near midnight followed by an increasing rate that peaked at 03:00 h. Changes in Omega arag and pH lagged behind Gnet throughout the daily cycle by two or more hours. The flux rate Pnet was the primary driver of calcification. Daytime coral metabolism rapidly removes dissolved inorganic carbon (DIC) from the bulk seawater and photosynthesis provides the energy that drives Gnet while increasing the bulk water pH. These relationships result in a correlation between Gnet and Omega arag, with Omega arag as the dependent variable. High rates of H+ efflux continued for several hours following mid-day peak Gnet suggesting that corals have difficulty in shedding waste protons as described by the Proton Flux Hypothesis. DIC flux (uptake) followed Pnet and Gnet and dropped off rapidly following peak Pnet and peak Gnet indicating that corals can cope more effectively with the problem of limited DIC supply compared to the problem of eliminating H+. Over a 24 h period the plot of total alkalinity (AT) versus DIC as well as the plot of Gnet versus Omega arag revealed a circular hysteresis pattern over the diel cycle in the coral and coral-algae mesocosms, but not the macroalgae mesocosm. Presence of macroalgae did not change Gnet of the corals, but altered the relationship between Omega arag and Gnet. Predictive models of how future global changes will effect coral growth that are based on oceanic Omega arag must include the influence of future localized Pnet on Gnet and changes in rate of reef carbonate dissolution. The correlation between Omega arag and Gnet over the diel cycle is simply the response of the CO2-carbonate system to increased pH as photosynthesis shifts the equilibria and increases the [CO3]2- relative to the other DIC components of [HCO3]- and [CO2]. Therefore Omega arag closely tracked pH as an effect of changes in Pnet, which also drove changes in Gnet. Measurements of DIC flux and H+ flux are far more useful than concentrations in describing coral metabolism dynamics. Coral reefs are systems that exist in constant disequilibrium with the water column.

Calibration of the maximum carboxylation velocity (Vcmax) using data mining techniques and ecophysiological data from the Brazilian Semiarid region, for use in Dynamic Global Vegetation Models.

The semiarid region of northeastern Brazil, the Caatinga, is extremely important due to its biodiversity and endemism. Measurements of plant physiology are crucial to the calibration of Dynamic Global Vegetation Models (DGVMs) that are currently used to simulate the responses of vegetation in face of global changes. In a field work realized in an area of preserved Caatinga forest located in Petrolina, Pernambuco, measurements of carbon assimilation (in response to light and CO2) were performed on 11 individuals of Poincianella microphylla, a native species that is abundant in this region. These data were used to calibrate the maximum carboxylation velocity (Vcmax) used in the INLAND model. The calibration techniques used were Multiple Linear Regression (MLR), and data mining techniques as the Classification And Regression Tree (CART) and K-MEANS. The results were compared to the UNCALIBRATED model. It was found that simulated Gross Primary Productivity (GPP) reached 72% of observed GPP when using the calibrated Vcmax values, whereas the UNCALIBRATED approach accounted for 42% of observed GPP. Thus, this work shows the benefits of calibrating DGVMs using field ecophysiological measurements, especially in areas where field data is scarce or non-existent, such as in the Caatinga

Evolution and challenges of dynamic global vegetation models for some aspects of plant physiology and elevated atmospheric CO2.

Dynamic global vegetation models (DGVMs) simulate surface processes such as the transfer of energy, water, CO2, and momentum between the terrestrial surface and the atmosphere, biogeochemical cycles, carbon assimilation by vegetation, phenology, and land use change in scenarios of varying atmospheric CO2 concentrations. DGVMs increase the complexity and the Earth system representation when they are coupled with atmospheric global circulation models (AGCMs) or climate models. However, plant physiological processes are still a major source of uncertainty in DGVMs. The maximum velocity of carboxylation (Vcmax), for example, has a direct impact over productivity in the models. This parameter is often underestimated or imprecisely defined for the various plant functional types (PFTs) and ecosystems. Vcmax is directly related to photosynthesis acclimation (loss of response to elevated CO2), a widely known phenomenon that usually occurs when plants are subjected to elevated atmospheric CO2 and might affect productivity estimation in DGVMs. Despite this, current models have improved substantially, compared to earlier models which had a rudimentary and very simple representation of vegetation?atmosphere interactions. In this paper, we describe this evolution through generations of models and the main events that contributed to their improvements until the current state-of-the-art class of models. Also, we describe some main challenges for further improvements to DGVMs.

Vocational psychological and organisational perspectives on career : towards a multidisciplinary dialogue

It has long been lamented that, although several disciplines contribute to career scholarship, they work in isolation from one another, thus denying career theory, research, and practice the benefits that multidisciplinary collaboration would bring. This constitutes a lost opportunity at a time when new understandings and approaches are needed in order to respond effectively to global changes in society and work. This book takes a major step towards remedying this situation by bringing together two key perspectives on career, the vocational psychological and the organisational (interpreted broadly to include organisation behaviour and human resource management). Written by international experts, the book opens by identifying some of the ���tributaries��� that flow into the ���great delta of careers scholarship���, and noting the need to link what are at present separate ���islands��� of scholarship. It is structured to allow comparison between the ways in which the two perspectives address career development and career management theory, research and interventions. It concludes by pointing to the possibilities for dialogue, and even collaboration, between these perspectives, and suggesting ways in which these could be brought about. The book will be essential reading for career scholars because, with its potential to stimulate new thinking and developments in theory and research and also, importantly, in practice (with beneficial spin-offs for policy-makers), this dialogue could open a new phase in career scholarship. With its overviews of the history, theory, research and practice of both perspectives, the book will also be a valuable resource for students of both perspectives.

Rethinking the notion of culture in the national history curriculum

Major global changes are placing new demands on the Australian education system. Recent statements by the Prime Minister, together with current education policy and national curriculum documents available in the public domain, look to education���s role in promoting economic prosperity and social cohesion. Collectively, they emphasise the need to equip young Australians with the knowledge, understandings and skills required to compete in the global economy and participate as engaged citizens in a culturally diverse world. However, the decision to prioritise discipline-based learning in the forthcoming Australian history curriculum without specifically encompassing culture as a referent, raises the following question. How will students acquire the cultural knowledge, understandings and skills necessary for this process? This paper addresses this question by situating the current push for a national history curriculum, with specific reference to the study of Indigenous history and the study of Asia in Australia.

iPed : pedagogy for digital text production

Reading and writing are being transformed by global changes in communication practices using new media technologies. This paper introduces iPed, a research-based pedagogy that enables teachers to navigate innovative digital text production in the literacy classroom. The pedagogy was generated in the context of a longitudinal digital literacy intervention in a school that services low-socioeconomic and ethnically diverse students. iPed synthesizes four key pedagogies that were salient in the analysis of over 180 hours of lesson observations ��� Link, Challenge, Co-Create, and Share. The strengths of the pedagogy include connecting to students��� home cultures, critical media literacy, collaborative and creative digital text production, and gaining cosmopolitan recognition within global communities.