Whatipu Beach, north Manukau Harbour, Auckland, has prograded episodically over 1.5 centuries. Sand dune vegetation is quantitatively described, and related to successional stage, local environment, and progradation dynamics. Foredunes, with fine, mobile, infertile sand, occupy the most recently prograded areas and are partially vegetated by native species. Instead of a dune slack, a stream which changed course to flow between dune ridges has created wet “sand river” vegetation. Relict fore‐dunes and a dune slack persist inland of the sand river, disrupting a lineal spatial sequence, as do rear dune wetlands. Less‐mobile grass and shrub communities, derived from Ammophila arenaria dunes, occupy surfaces >50 years old. No climax communities are present. In contrast to spatial analogues, the Whatipu dunes demonstrate how rapidly succession proceeds in response to the formation of new habitat, while freshwater movements generate non‐seral sand‐river communities. Succession is modified by invading exotics and by the absence of many disturbance‐intolerant native shrub species. Coastal progradation rates at Whatipu indicate that shrubland develops within 50 years, suggesting that spatial analogues of dune succession can mis‐represent the longevity of early seral stages. These unusual successional patterns on dateable surfaces, and the presence of rare flora and fauna, make Whatipu Beach important for conservation.

The role of ecosystem engineers (EE) in the formation of ombrotrophic mires (bogs) from fens, called the fen–bog transition (FBT), can be best understood through categorization of the autogenic and allogenic processes causing bog initiation. Here we review these pathways, discuss the drivers of change in both cases, and tabulate an approach for distinguishing between them. We then compare the engineering ability of acknowledged and putative engineers against a number of characters which plants require to cross the FBT, and to stabilize occupancy on the bog side. While some Sphagnum spp. are accepted as the EE of the fen–bog transition in northern hemisphere bogs, they appear unimportant in New Zealand. Instead their role appears to be occupied by a restiad, Empodisma minus , a plant with leafless, wiry stems and capillaroid roots. Empodisma minus appears capable of engineering autogenic transitions from fen to bog across New Zealand, even more efficiently than Sphagnum .

Pimelea arenaria , an endangered native sand dune plant, appears to be experiencing recruitment failure. The structure of four populations from the lower North Island, New Zealand, was examined for recruitment patterns, while one population was examined for flowering, pollination, and seed germination limits on regeneration. Line transects and searches found no seedlings, and measures of individual plant sizes ( n = 331) showed bias towards medium, with some large, individuals, suggesting recruitment failure at all sites. Flowers are plentiful. The standing crop of nectar was c. 0.4–0.9 joules per hermaphrodite flower, with insects appearing to be the main pollen vectors. Pollination manipulations were carried out on both genders at one site, with fruit set measured from natural, hand out‐crossed, and pollinator‐exclusion treatments. Female flowers do not appear to be pollen limited as natural fruit set is only non‐significantly lower than that in hand‐out‐crossed flowers. Only hermaphrodite plants selfed autonomously, with nearly 90% producing fruit. One quarter of the seed from both female and hermaphrodite flowers germinated. Results suggest that recruitment failure of Pimelea arenaria is not due to reproductive biology, pollen limitation, or poor seed germination. Therefore, recruitment failure probably occurs during the seedling establishment phases, due to environmental pressures and/or predation.

Urban areas are an important conduit for alien invaders. A floristic study was made of the spontaneously occurring plant species of 11 towns in the lower North Island. Four hundred and eighty‐three species were found, from 93 families. Viola sepincula and Sarcococca ruscifolia are recorded as naturalised for the first time. Only Poa annua occurred in > 50% of plots. The majority of species originated from Eurasia and the Mediterranean, having arrived accidentally. A third are annuals and 89% are exotics. Basically homogenous, small floristic differences between towns appear to be related to either chance invasion events or to the environment. Influential environmental factors include the distance to the coast and the size of the central business district. The inland tourist town of Taupo is the most extreme, separated from warmer, coastal, more isolated towns, and from larger, more developed centres. The underlying homogeneity of New Zealand urban floras appears to be due to their recent and relatively uniform history of colonisation and urbanisation.

Background: Precipitation influences the vulnerability of grassland ecosystems, especially upland grasslands, and soil respiration is critical for carbon cycling in arid grassland ecosystems which typically experience more droughty conditions. Methods: We used three precipitation treatments to understand the effect of precipitation on soil respiration of a typical arid steppe in the Loess Plateau in north-western China. Precipitation was captured and relocated to simulate precipitation rates of 50%, 100%, and 150% of ambient precipitation. Results and Discussion: Soil moisture was influenced by all precipitation treatments. Shoot biomass was greater, though non-significantly, as precipitation increased. However, both increase and decrease of precipitation significantly reduced root biomass. There was a positive linear relationship between soil moisture and soil respiration in the study area during the summer (July and August), when most precipitation fell. Soil moisture, soil root biomass, pH, and fungal diversity were predictors of soil respiration based on partial least squares regression, and soil moisture was the best of these. Conclusion: Our study highlights the importance of increased precipitation on soil respiration in drylands. Precipitation changes can cause significant alterations in soil properties, microbial fungi, and root biomass, and any surplus or transpired moisture is fed back into the climate, thereby affecting the rate of soil respiration in the future.