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An introduction to the journal is presented in which the editor discusses an article on the impact of natural drought in Amazon, the quality of various global circulation models (GCMs) climate situations which are employed to drive dynamic global vegetation models (DGVMs), and the mechanisms involve in DGVM processes.

•Second-generation Dynamic Global Vegetation Models (DGVMs) have recently been developed that explicitly represent the ecological dynamics of disturbance, vertical competition for light, and succession. Here, we introduce a modified second-generation DGVM and examine how the representation of demographic processes operating at two-dimensional spatial scales not represented by these models can influence predicted community structure, and responses of ecosystems to climate change. •The key demographic processes we investigated were seed advection, seed mixing, sapling survival, competitive exclusion and plant mortality. We varied these parameters in the context of a simulated Amazon rainforest ecosystem containing seven plant functional types (PFTs) that varied along a trade-off surface between growth and the risk of starvation induced mortality. •Varying the five unconstrained parameters generated community structures ranging from monocultures to equal co-dominance of the seven PFTs. When exposed to a climate change scenario, the competing impacts of CO2 fertilization and increasing plant mortality caused ecosystem biomass to diverge substantially between simulations, with mid-21st century biomass predictions ranging from 1.5 to 27.0 kg C m−2. •Filtering the results using contemporary observation ranges of biomass, leaf area index (LAI), gross primary productivity (GPP) and net primary productivity (NPP) did not substantially constrain the potential outcomes. We conclude that demographic processes represent a large source of uncertainty in DGVM predictions. [ABSTRACT FROM AUTHOR]

•Experimental evidence demonstrates a higher efficiency of water and nitrogen use in C4 compared with C3 plants, which is hypothesized to drive differences in biomass allocation between C3 and C4 species. However, recent work shows that contrasts between C3 and C4 grasses may be misinterpreted without phylogenetic control. •Here, we compared leaf physiology and growth in multiple lineages of C3 and C4 grasses sampled from a monophyletic clade, and asked the following question: which ecophysiological traits differ consistently between photosynthetic types, and which vary among lineages? •C4 species had lower stomatal conductance and water potential deficits, and higher water-use efficiency than C3 species. Photosynthesis and nitrogen-use efficiency were also greater in C4 species, varying markedly between clades. Contrary to previous studies, leaf nitrogen concentration was similar in C4 and C3 types. Canopy mass and area were greater, and root mass smaller, in the tribe Paniceae than in most other lineages. The size of this phylogenetic effect on biomass partitioning was greater in the C4 NADP-me species than in species of other types. •Our results show that the phylogenetic diversity underlying C4 photosynthesis is critical to understanding its functional consequences. Phylogenetic bias is therefore a crucial factor to be considered when comparing the ecophysiology of C3 and C4 species. [ABSTRACT FROM AUTHOR]

Measurements of the net CO2 flux between terrestrial ecosystems and the atmosphere using the eddy covariance technique have the potential to underpin our interpretation of regional CO2 source–sink patterns, CO2 flux responses to forcings, and predictions of the future terrestrial C balance. Information contained in FLUXNET eddy covariance data has multiple uses for the development and application of global carbon models, including evaluation/validation, calibration, process parameterization, and data assimilation. This paper reviews examples of these uses, compares global estimates of the dynamics of the global carbon cycle, and suggests ways of improving the utility of such data for global carbon modelling. Net ecosystem exchange of CO2 (NEE) predicted by different terrestrial biosphere models compares favourably with FLUXNET observations at diurnal and seasonal timescales. However, complete model validation, particularly over the full annual cycle, requires information on the balance between assimilation and decomposition processes, information not readily available for most FLUXNET sites. Site history, when known, can greatly help constrain the model-data comparison. Flux measurements made over four vegetation types were used to calibrate the land-surface scheme of the Goddard Institute for Space Studies global climate model, significantly improving simulated climate and demonstrating the utility of diurnal FLUXNET data for climate modelling. Land-surface temperatures in many regions cool due to higher canopy conductances and latent heat fluxes, and the spatial distribution of CO2 uptake provides a significant additional constraint on the realism of simulated surface fluxes. FLUXNET data are used to calibrate a global production efficiency model (PEM). [ABSTRACT FROM AUTHOR]

The author reflects regarding the conservation of biodiversity. He various factors that contributes to the biodiversity destruction which include the global scale travel of plants and people and intervention of human for the replacement of natural vegetation. He mentions that the result for the molecular approaches application to diversity which provided qualified and quantified hypotheses in geographical locations and species variety can help to give clarity for biodiversity conservation.

The author reflects on the theory of plant science used in the sections of publications in "New Phytologist." He says that the development of plant science is based the development of theories. It says that papers in the environment section provide new theory are approaches to collect data sets of observations such as recovery from stem damage and impacts of precipitation on desert productivity. Moreover, the deductive and inductive approaches to research offers new insights and hypothesis.

The author reflects on how editorial views of the journal changed over time since the first issue was published in 1902 until the issues in 2011 regarding forest fires. The author mentions an article in 1906 by F. E. Weiss that discusses the importance of fires in vegetation in Natal, South Africa that cites the fire resistant Vellozia plant and the use of fire to control cattle tick infestations. The author adds that after 100 years, fire importance to vegetation is still an interesting topic.

The article discusses various reports published within the issue, including one by Ralph Panstruga on plant-biotrophic fungal disease interactions and one by Hongzhi Kong on the development of genetic controls and molecular mechanisms which involved the evolution of flowers.

The article discusses various reports published within the issue, including one by Colleen Iversen on carbon dioxide in forested ecosystems, another by Katherine McCullogh on a moving water well, and another one by Rebecca Mosher on maternal control of endosperms.

The authors reflect on the research by Frederic Lens and colleagues which won the 2010 Tansley Medal from the journal "New Phytologist." They state that the research offers insights on the association between the anatomy of wood and hydraulic conductivity in trees. They mention that Lens and colleagues used various techniques and examined seven taxa of the genus Acer, resulting to the influences of membrane thickness, porosity, and lower xylem conductivity to cavitation resistance.

The author reflects on floral design. He argues that the basis of the binomial classification of flowering plants are the differences in flower design and that most species differ in some observable design characteristics. An overview of the experimental approach of Charles Darwin in his study on the evolutionary consequences of floral mechanisms is offered. He suggests applying a wide range of ecological, developmental and theoretical techniques in identifying the differences of flowers.

• Theoretically, communities at or near their equilibrium species number resist entry of new species. Such 'biotic resistance' recently has been questioned because of successful entry of alien species into diverse natural communities. • Data on 10,409 naturalizations of 5350 plant species over 16 sites dispersed globally show exponential distributions both for species over sites and for sites over number of species shared. These exponentials signal a statistical mechanics of species distribution, assuming two conditions. First, species and sites are equivalent, either identical ('neutral') or so complex that the chance a species is in the right place at the right time is vanishingly small ('idiosyncratic'); the range of species and sites in our data disallows a neutral explanation. Secondly, the total number of naturalizations is fixed in any era by a 'regulator'. • Previous correlation of species naturalization rates with net primary productivity over time suggests that the regulator is related to productivity. • We conclude that biotic resistance is a moving ceiling, with resistance controlled by productivity. The general observation that the majority of species occur naturally at only a few sites, and only a few species occur at many sites, now has a quantitative (exponential) character, offering the study of species' distributions a previously unavailable rigor., (© 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.)

The dynamic relationship between vegetation and climate is now widely acknowledged. Climate influences the distribution of vegetation; and through a number of feedback mechanisms vegetation affects climate. This implies that land-use changes such as deforestation will have climatic consequences. However, the spatial scales at which such feedbacks occur remain largely unknown. Here, we use a large database of precipitation and tree cover records for an area of the biodiversity-rich Atlantic forest region in south eastern Brazil to investigate the forest-rainfall feedback at a range of spatial scales from ca 10(1)-10(4) km2. We show that the strength of the feedback increases up to scales of at least 10(3) km2, with the climate at a particular locality influenced by the pattern of landcover extending over a large area. Thus, smaller forest fragments, even if well protected, may suffer degradation due to the climate responding to land-use change in the surrounding area. Atlantic forest vertebrate taxa also require large areas of forest to support viable populations. Areas of forest of ca 10(3) km2 would be large enough to support such populations at the same time as minimizing the risk of climatic feedbacks resulting from deforestation.