Plant species radiations: where, when, why?

The spatial and temporal patterns of plant species radiations are largely unknown. I used a nonlinear regression to estimate speciation and extinction rates from all relevant dated clades. Both are surprisingly high. A high species richness can be the result of either little extinction, thus preserving the diversity that dates from older radiations (a ‘mature radiation’), or a ‘recent and rapid radiation’. The analysis of radiations from different regions (Andes, New Zealand, Australia, southwest Africa, tropics and Eurasia) revealed that the diversity of Australia may be largely the result of mature radiations. This is in sharp contrast to New Zealand, where the flora appears to be largely the result of recent and rapid radiations. Mature radiations are characteristic of regions that have been climatically and geologically stable throughout the Neogene, whereas recent and rapid radiations are more typical of younger (Pliocene) environments. The hyperdiverse Cape and Neotropical floras are the result of the combinations of mature as well as recent and rapid radiations. Both the areas contain stable environments (the Amazon basin and the Cape Fold Mountains) as well as dynamic landscapes (the Andes and the South African west coast). The evolution of diversity can only be understood in the context of the local environment.

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Species delimitation and phylogeny of a New Zealand plant species radiation

BMC Evolutionary Biology ◽

10.1186/1471-2148-9-111 ◽

2009 ◽

Vol 9 (1) ◽

pp. 111 ◽

Cited By ~ 41

Author(s):

Heidi M Meudt ◽

Peter J Lockhart ◽

David Bryant

Keyword(s):

New Zealand ◽

Plant Species ◽

Species Delimitation ◽

Species Radiation

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Evaluating the effect of nutrient redistribution by animals on the phosphorus cycle of lowland Amazonia

Biogeosciences ◽

10.5194/bg-15-279-2018 ◽

2018 ◽

Vol 15 (1) ◽

pp. 279-295 ◽

Cited By ~ 1

Author(s):

Corina Buendía ◽

Axel Kleidon ◽

Stefano Manzoni ◽

Björn Reu ◽

Amilcare Porporato

Keyword(s):

Amazon Basin ◽

P Availability ◽

Phosphorus Cycle ◽

Terra Firme ◽

The Andes ◽

P Content ◽

Spatial Redistribution ◽

Soil Age ◽

Seasonally Flooded ◽

Lowland Amazonia

Abstract. Phosphorus (P) availability decreases with soil age and potentially limits the productivity of ecosystems growing on old and weathered soils. Despite growing on ancient soils, ecosystems of lowland Amazonia are highly productive and are among the most biodiverse on Earth. P eroded and weathered in the Andes is transported by the rivers and deposited in floodplains of the lowland Amazon basin creating hotspots of P fertility. We hypothesize that animals feeding on vegetation and detritus in these hotspots may redistribute P to P-depleted areas, thus contributing to dissipate the P gradient across the landscape. Using a mathematical model, we show that animal-driven spatial redistribution of P from rivers to land and from seasonally flooded to terra firme (upland) ecosystems may sustain the P cycle of Amazonian lowlands. Our results show how P imported to land by terrestrial piscivores in combination with spatial redistribution of herbivores and detritivores can significantly enhance the P content in terra firme ecosystems, thereby highlighting the importance of food webs for the biogeochemical cycling of Amazonia.

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Modelling the abundance of three key plant species in New Zealand hill-pasture using a decision tree approach

Ecological Modelling ◽

10.1016/j.ecolmodel.2009.04.031 ◽

2009 ◽

Vol 220 (15) ◽

pp. 1819-1825 ◽

Cited By ~ 3

Author(s):

Liqiang Wan ◽

Baisen Zhang ◽

Peter Kemp ◽

Xianglin Li

Keyword(s):

New Zealand ◽

Decision Tree ◽

Plant Species ◽

Tree Approach

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Extreme Drought Events over the Amazon Basin: The Perspective from the Reconstruction of South American Hydroclimate

Water ◽

10.3390/w10111594 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1594 ◽

Cited By ~ 6

Author(s):

Beatriz Garcia ◽

Renata Libonati ◽

Ana Nunes

Keyword(s):

Surface Temperature ◽

Extreme Events ◽

General Circulation ◽

Amazon Basin ◽

General Circulation Models ◽

Extreme Drought ◽

Severe Drought ◽

South American ◽

Spatial And Temporal Patterns ◽

Near Surface

The Amazon basin has experienced severe drought events for centuries, mainly associated with climate variability connected to tropical North Atlantic and Pacific sea surface temperature anomalous warming. Recently, these events are becoming more frequent, more intense and widespread. Because of the Amazon droughts environmental and socioeconomic impacts, there is an increased demand for understanding the characteristics of such extreme events in the region. In that regard, regional models instead of the general circulation models provide a promising strategy to generate more detailed climate information of extreme events, seeking better representation of physical processes. Due to uneven spatial distribution and gaps found in station data in tropical South America, and the need of more refined climate assessment in those regions, satellite-enhanced regional downscaling for applied studies (SRDAS) is used in the reconstruction of South American hydroclimate, with hourly to monthly outputs from January 1998. Accordingly, this research focuses on the analyses of recent extreme drought events in the years of 2005 and 2010 in the Amazon Basin, using the SRDAS monthly means of near-surface temperature and relative humidity, precipitation and vertically integrated soil moisture fields. Results from this analysis corroborate spatial and temporal patterns found in previous studies on extreme drought events in the region, displaying the distinctive features of the 2005 and 2010 drought events.

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Competitive abilities of three indigenous New Zealand plant species in relation to the introduced plant Hieracium pilosella

Basic and Applied Ecology ◽

10.1078/1439-1791-00052 ◽

2001 ◽

Vol 2 (3) ◽

pp. 243-250 ◽

Cited By ~ 12

Author(s):

Jon Moen ◽

Colin D. Meurk

Keyword(s):

New Zealand ◽

Plant Species ◽

Hieracium Pilosella ◽

Competitive Abilities

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Functional Ecology of Iceplant Taxa and Their Role in Eco-restoration of New Zealand Sand Dunes

10.26686/wgtn.17000419 ◽

2021 ◽

Author(s):

◽

Guyo Duba Gufu

Keyword(s):

New Zealand ◽

Plant Species ◽

Plant Communities ◽

Growth Rates ◽

Sand Dunes ◽

Intergeneric Hybrid ◽

Leaf Production ◽

Natural Plant ◽

Carpobrotus Edulis

<p>Biological invasion by non-native plant species has often been cited as a cause of native biodiversity loss. While the outcome of species invasions depends on interactions between exotic and resident native species, most studies of biological invasions have focused solely on the direct negative impacts of non-indigenous species on native biota. Although investigations of the role of competition in shaping natural plant communities were dominant in the previous generations and are still popular, more recent experimental research has uncovered the striking influence of facilitation on community dynamics. This thesis aims to investigate competitive and facilitative influence of the invasive South African iceplant (Carpobrotus edulis) on Spinifex sericeus, a native foredune grass species, with particular reference to implications of these interactions for dune restoration in New Zealand. It further explores the growth rates, substrate preferences and mating systems of the exotic and native iceplant taxa found in New Zealand. I begin by briefly outlining the influence of competition and facilitation on natural plant communities with reference to the role of facilitation in eco-restoration. I also give a few examples where exotic species have been found to facilitate native ones. Secondly, a neighbour removal experiment was conducted on coastal sand dunes with the main aim of studying the effects of Carpobrotus edulis on establishment of Spinifex sericeus at the foredune region. Finally, I compared the growth rates of the most widely distributed iceplant taxa in New Zealand in different substrates and the breeding systems of the exotic Carpobrotus. Examples abound in literature of exotic plant species facilitating native ones especially in forestry. In the neighbour removal study, Carpobrotus edulis protected Spinifex seedlings against storm erosion, sandblasting and salt sprays while at the same time suppressing its leaf production. Suppression of Spinifex leaf production was more pronounced at top of the dune where stress elements is presumably more benign. There was no evidence of allelopathic suppression of Spinifex by C. edulis. Only Carpobrotus chilensis displayed some level of substrate preference by putting on relatively lower biomass in gravel. The exotic Carpobrotus spp. put on greater dry matter content than the native Disphyma australe and the Carpobrotus-x-Disphyma hybrid. The hybrid displayed a faster vegetative growth rate whereas D. australe allocated relatively more biomass to the roots than the shoot. Both Carpobrotus spp. are self compatible and highly capable of intrageneric and intergeneric hybridisation. Mass removal of the existing exotic iceplant stands from foredunes along high energy coasts is not advisable as they serve as useful stabilisers. The intergeneric hybrid is sexually sterile with sparsely spread stolons that could allow co-occurrence with other species and therefore is more suitable for foredune stabilisation. However, more research needs to be conducted on the ecology of the intergeneric hybrid.</p>

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Sensitivity of precipitation in the highlands and lowlands of Peru to physics parameterization options in WRFV3.8.1

10.5194/gmd-2021-307 ◽

2021 ◽

Author(s):

Santos J. González-Rojí ◽

Martina Messmer ◽

Christoph C. Raible ◽

Thomas F. Stocker

Keyword(s):

Observational Data ◽

Amazon Basin ◽

Cumulus Parameterization ◽

Data Sets ◽

Monthly Precipitation ◽

Microphysics Scheme ◽

The Andes ◽

Station Data ◽

Pattern Correlation ◽

Simulated Precipitation

Abstract. The performance of the Weather Research and Forecasting (WRF) model version 3.8.1 at convection-permitting scale is evaluated by means of several sensitivity simulations over southern Peru down to a grid resolution of 1 km, whereby the main focus is on the domain with 5 km horizontal resolution. Different configurations of microphysics, cumulus, longwave radiation and planetary boundary layer schemes are tested. For the year 2008, the simulated precipitation amounts and patterns are compared to gridded observational data sets and weather station data gathered from Peru, Bolivia and Brazil. The temporal correlation of simulated monthly precipitation sums against in-situ and gridded observational data show that the most challenging regions for WRF are the slopes along both sides of the Andes, i.e., elevations between 1000 and 3000 m above sea level. The pattern correlation analysis between simulated precipitation and station data suggests that all tested WRF setups perform rather poorly along the northeastern slopes of the Andes during the entire year. In the southwestern region of the domain the performance of all setups is better except for the driest period (May–September). The results of the pattern correlation to the gridded observational data sets show that all setups perform reasonably well except along both slopes during the dry season. The precipitation patterns reveal that the typical setup used over Europe is too dry throughout the entire year, and that the experiment with the combination of the single-moment 6-class microphysics scheme and the Grell–Freitas cumulus parameterization in the domains with resolutions larger than 5 km, suitable for East Africa, does not perfectly apply to other equatorial regions such as the Amazon basin in southeastern Peru. The experiment with the Stony–Brook University microphysics scheme and the Grell-Freitas cumulus parameterization tends to overestimate precipitation over the northeastern slopes of the Andes, but allows to enforce a positive feedback between the soil moisture, air temperature, relative humidity, mid-level cloud cover and finally, also precipitation. Hence, this setup is the one providing the most accurate results over the Peruvian Amazon, and particularly over the department of Madre de Dios, which is a region of interest because it is considered the biodiversity hotspot of Peru. The robustness of this particular parameterization option is backed up by similar results obtained during wet climate conditions observed in 2012.

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Interactive effects of climate change and plant invasion on alpine biodiversity and ecosystem dynamics

10.26686/wgtn.17138738.v1 ◽

2021 ◽

Author(s):

◽

Justyna Giejsztowt

Keyword(s):

Climate Change ◽

New Zealand ◽

Plant Species ◽

Climate Warming ◽

Plant Invasion ◽

Invasive Plant ◽

Ecosystem Dynamics ◽

Interactive Effects ◽

Native Plant ◽

Competition For Pollination

<p>Drivers of global change have direct impacts on the structure of communities and functioning of ecosystems, and interactions between drivers may buffer or exacerbate these direct effects. Interactions among drivers can lead to complex non-linear outcomes for ecosystems, communities and species, but are infrequently quantified. Through a combination of experimental, observational and modelling approaches, I address critical gaps in our understanding of the interactive effects of climate change and plant invasion, using Tongariro National Park (TNP; New Zealand) as a model. TNP is an alpine ecosystem of cultural significance which hosts a unique flora with high rates of endemism. TNP is invaded by the perennial shrub Calluna vulgaris (L.) Hull. My objectives were to: 1) determine whether species-specific phenological shifts have the potential to alter the reproductive capacity of native plants in landscapes affected by invasion; 2) determine whether the effect of invasion intensity on the Species Area Relationship (SAR) of native alpine plant species is influenced by environmental stress; 3) develop a novel modelling framework that would account for density-dependent competitive interactions between native species and C. vulgaris and implement it to determine the combined risk of climate change and plant invasion on the distribution of native plant species; and 4) explore the possible mechanisms leading to a discrepancy in C. vulgaris invasion success on the North and South Islands of New Zealand. I show that species-specific phenological responses to climate warming increase the flowering overlap between a native and an invasive plant. I then show that competition for pollination with the invader decreases the sexual reproduction of the native in some landscapes. I therefore illustrate a previously undescribed interaction between climate warming and plant invasion where the effects of competition for pollination with an invader on the sexual reproduction of the native may be exacerbated by climate warming. Furthermore, I describe a previously unknown pattern of changing invasive plant impact on SAR along an environmental stress gradient. Namely, I demonstrate that interactions between an invasive plant and local native plant species richness become increasingly facilitative along elevational gradients and that the strength of plant interactions is dependent on invader biomass. I then show that the consequences of changing plant interactions at a local scale for the slope of SAR is dependent on the pervasion of the invader. Next, I demonstrate that the inclusion of invasive species density data in distribution models for a native plant leads to greater reductions in predicted native plant distribution and density under future climate change scenarios relative to models based on climate suitability alone. Finally, I find no evidence for large-scale climatic, edaphic, and vegetative limitations to invasion by C. vulgaris on either the North and South Islands of New Zealand. Instead, my results suggest that discrepancies in invasive spread between islands may be driven by human activity: C. vulgaris is associated with the same levels of human disturbance on both islands despite differences in the presence of these conditions between then islands. Altogether, these results show that interactive effects between drivers on biodiversity and ecosystem dynamics are frequently not additive or linear. Therefore, accurate predictions of global change impacts on community structure and ecosystems function require experiments and models which include of interactions among drivers such as climate change and species invasion. These results are pertinent to effective conservation management as most landscapes are concurrently affected by multiple drivers of global environmental change.</p>

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Extended distribution and host plants of Nameriophyes sapidae Xue & Zhang 2008 (Acari: Eriophyidae) in New Zealand

Zootaxa ◽

10.11646/zootaxa.2796.1.6 ◽

2011 ◽

Vol 2796 (1) ◽

pp. 67

Author(s):

NICHOLAS A. MARTIN ◽

ZHI-QIANG ZHANG

Keyword(s):

New Species ◽

New Zealand ◽

Plant Species ◽

Host Plants ◽

Mite Species ◽

Native Plant ◽

Native Plant Species ◽

The North ◽

A New Species

Nameriophyes sapidae Xue & Zhang (Acari: Eriophyidae) was found on transplanted nikau palms, Rhopalostylis sapida (H. Wendl. & Drude) in Auckland, New Zealand and described as a new species (Xue & Zhang 2008). Although R. sapida is a native plant species, it was not known if this mite species was indigenous or adventive because it was collected only from transplanted palms in unnatural gardens in Auckland. A survey was undertaken of R. sapida and the Kermadec Island palm, Rhopalostylis baueri (Hook. f.) Wendl. & Drude in the northern part of the North Island and Chatham Island.

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