Ecologists have long sought to understand the factors controlling the structure of savanna vegetation. Using data from 2154 sites in savannas across Africa, Australia, and South America, we found that increasing moisture availability drives increases in fire and tree basal area, whereas fire reduces tree basal area. However, among continents, the magnitude of these effects varied substantially, so that a single model cannot adequately represent savanna woody biomass across these regions. Historical and environmental differences drive the regional variation in the functional relationships between woody vegetation, fire, and climate. These same differences will determine the regional responses of vegetation to future climates, with implications for global carbon stocks.

A series of trials were carried out using cassava (Manihot esculenta Crantz). Crop growth rate increased with leaf area (LAI) up to LAI 4; root growth rate increased up to LAI 3 to 3.5, then declined. Leaf area index is determined by leaf size, leaf formation rate, and individual leaf life. Leaf size reached a maximum 4 months after planting and then decreased; the maximumw as a varietal character. Leaf life was reduced by shading but in full daylight was determined by a variety. Leaf formation rate per shoot apex showed little genetic variation and declined with time; large differences in leaf formation rate per plant were determined by differences in branching pattern. Top growth had preference over root growth, and root sink was not limiting when root number per plant was nine or more.A computer program was written to implement a dynamic growth model which suggests that high‐yielding plants will branch late in life and possess large leaves and long leaf life. Potential yields of more than 25 metric tons/ha per year of dry roots are obtainable at 400 to 450 g cal cm−2 day radiation.

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We introduce a dataset of biological, ecological, conservation and legal information for every species and subspecies of Australian bird, 2056 taxa or populations in total. Version 1 contains 230 fields grouped under the following headings: Taxonomy & nomenclature, Phylogeny, Australian population status, Conservation status, Legal status, Distribution, Morphology, Habitat, Food, Behaviour, Breeding, Mobility and Climate metrics. It is envisaged that the dataset will be updated periodically with new data for existing fields and the addition of new fields. The dataset has already had, and will continue to have applications in Australian and international ornithology, especially those that require standard information for a large number of taxa.

Aim (1) To describe the spatio-temporal patterns of mass-flowering and die-off in a long-lived, semelparous, clumping bamboo, Bambusa arnhemica, at landscape and local scales. (2) To discuss causal processes in the flowering patterns of semelparous bamboos.Location The entire range of B. arnhemica, in the monsoonal, tropical, northwest of the Northern Territory of Australia, mostly along watercourses.Methods Landscape-scale flowering patterns were assessed by a combination of air, boat and ground survey in each year from 2000 to 2002. Areas that flowered prior to 2000, and those in which no flowering occurred, were also recorded, and historic records collated. At local scales, initiation of flowering, rates of die-off, and subsequent germination densities of seedlings were quantified by groundbased counts.Results After an estimated 40-50 years of vegetative development, B. arnhemica flowered, seeded prolifically, then died. Flowering occurred synchronously within patches ranging from 0.002 to 3200 km 2 . One or more patches flowered in successive years from 1996 to 2002, forming a temporally-structured but spatially-chaotic flowering wave that affected c. 80% of the population. Synchronous flowering took the form of a flowering distribution in which over 95% of clumps within a patch initiated flowering in a central year, most of the remainder flowering the year before or after. Along the Daly River, an exception was observed in which 56% of clumps flowered in the peak year. Seedling densities were three orders of magnitude greater under clumps that flowered in the central rather than the leading year of the flowering distribution.Main conclusions Synchrony is argued to be the primal state in semelparous bamboos, promoted by intense selection acting on a endogenous (genetic or biological) clock whose influence largely overrides that of the environment. A flowering wave may develop within an initially synchronous population when stochastic events interact with the biological clock without permanently altering the clock setting, producing an off-set patch. Off-set groups may only survive if sufficient individuals are off-set by the same amount at the same time and in the same vicinity so as to produce a new synchronously-flowering patch. This could be driven by two processes. Inter-year climatic variation may alter the biological clock's perception of time, producing off-sets at local or regional scales or even affecting entire populations. Severe environmental pressures may also force oneoff changes to flowering schedules, as suggested by a severe flood event prior to flowering on the Daly River. A dynamic hypothesis for a wider range of bamboo flowering patterns is proposed in which synchronous flowering is fragmented and disrupted over time but renewed by allochronic speciation and dispersal.