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1.
Ecol Appl ; 32(6): e2613, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35366034

RESUMO

Connecting scientific research and government policy is essential for achieving objectives in sustaining biodiversity in an economic context. Our approach to connecting theoretical ecology, applied ecology, and policy was devised using principles of restoration ecology and the requisite methodology to restore biodiverse ecosystems. Using a threatened ecological community (TEC) with >120 plant species, we posit our approach as a guide for interpreting and achieving regulatory compliance (i.e., government conditions) enacted to manage or offset environmental impacts of development. We inform the scientific approach necessary to delivering outcomes appropriate to policy intent and biodiverse restoration through theoretical and applied research into the ecological restoration of the highly endemic flora of banded ironstone formations of the Mid West of Western Australia. Our approach (1) defines scale-appropriate restoration targets that meet regulatory compliance (e.g., Government of Western Australia Ministerial Conditions); (2) determines the optimal method to return individual plant species to the restoration landscape; (3) develops a conceptual model for our system, based on existing restoration frameworks, to optimize and facilitate the pathway to the restoration of a vegetation community (e.g., TEC) using diverse research approaches; and (4) develops an assessment protocol to compare restoration achievements against the expected regulatory outcomes using our experimental restoration trials as a test example. Our approach systematically addressed the complex challenges in setting and achieving restoration targets for an entire vegetation community, a first for a semiarid environment. We interpret our approach as an industry application relevant to policy- or regulator-mediated mine restoration programs that seek to return biodiverse species assemblages at landscape scales.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Conservação dos Recursos Naturais/métodos , Plantas , Austrália Ocidental
2.
Heredity (Edinb) ; 102(3): 274-85, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19002205

RESUMO

In plants, pollen- and seed-dispersal distributions are characteristically leptokurtic, with significant consequences for spatial genetic structure and nearest-neighbour mating. However, most studies to date have been on wind- or insect-pollinated species. Here, we assigned paternity to quantify effective pollen dispersal over 9 years of mating, contrasted this to seed dispersal and examined their effects on fine-scale spatial genetic structure, within the bird-pollinated shrub Banksia hookeriana (Proteaceae). We used 163 polymorphic amplified fragment length polymorphism markers to assess genetic structure and pollen dispersal in a spatially discrete population of 112 plants covering 0.56 ha. Spatial autocorrelation analysis detected spatial genetic structure in the smallest distance class of 0-5 m (r=0.025), with no significant structure beyond 8 m. Experimentally quantified seed-dispersal distances for 337 seedlings showed a leptokurtic distribution around a median of 5 m, reaching a distance of 36 m. In marked contrast, patterns of pollen dispersal for 274 seeds departed strikingly from typical near-neighbour pollination, with a distribution largely corresponding to the spatial distribution of plants. We found very high multiple paternity, very low correlated paternity and an equal probability of siring for the 50 closest potential mates. Extensive pollen carryover was demonstrated by multiple siring in 83 of 86 (96.5%) two-seeded fruits. Highly mobile nectar-feeding birds facilitate this promiscuity through observed movements that were effectively random. As the incidence of bird-pollination is markedly greater in the Southwest Australian Floristic Region than elsewhere, our results have broad and novel significance for the evolution and conservation for many species in Gondwanan lineages.


Assuntos
Aves/fisiologia , Pólen/genética , Polinização , Proteaceae/genética , Sementes/genética , Animais , Comportamento Animal , Pólen/fisiologia , Proteaceae/fisiologia , Sementes/fisiologia
3.
Ecology ; 88(9): 2292-304, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17918407

RESUMO

The fire-prone shrublands of southwestern Australia are renowned for their high plant species diversity and prominence of canopy seed storage (serotiny). We compared species richness, abundance, and life history attributes for soil and canopy seed banks in relation to extant vegetation among four sites with different substrate conditions and high species turnover (50-80%) to identify whether this unusual community-level organization of seed storage might contribute to maintenance of high species richness. Soil seed bank (SSB) densities were low to moderate (233-1435 seeds/m2) compared with densities for other Mediterranean-type vegetation and were lowest for sites with highest canopy seed bank (CSB) species richness and lowest nutrient availability, but not richness or abundance of resprouters. Annuals were infrequent in the lowest nutrient sites, but there was no evidence that small SSB size was due to low seed inputs or a trade-off between seed production/storage and seed size in response to low nutrient availability. Sorensen's similarity between SSB and extant vegetation was 26-43% but increased to 54-57% when the CSB was included, representing levels higher than reported for most other ecosystems. Resprouting species were well represented in both the SSB and CSB, and there was no evidence for lower seed production in resprouters than in non-sprouters overall. The SSB and CSB held no species in common and were characterized by markedly different seed dispersal attributes, with winged or small seeds in the CSB and seeds dispersed by ants, birds, and wind (though none with wings) in the SSB. There was no evidence of spatial differentiation in the distribution of seeds of SSB species between vegetated and open microsites that might facilitate species coexistence, but most woody non-sprouters showed aggregation at scales of 1-2 m, implying limited seed dispersal. High similarity between overall seed bank (SSB + CSB) and extant species composition, high number of resprouting species, and seed dispersal processes before (SSB) and after fire (CSB) leading to differential spatial aggregation of post-fire recruits from the two seed bank types may buffer species composition against rapid change and provide a mechanism for maintaining species coexistence at the local scale.


Assuntos
Biodiversidade , Ecossistema , Fenômenos Fisiológicos Vegetais , Sementes/fisiologia , Solo , Austrália , Desenvolvimento Vegetal , Dinâmica Populacional , Sementes/crescimento & desenvolvimento , Especificidade da Espécie
4.
J Evol Biol ; 16(4): 551-7, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14632219

RESUMO

Putative hybrids between Banksia hookeriana and B. prionotes were identified among 12 of 106 populations of B. hookeriana located at or near anthropogenically disturbed sites, mainly roadways, but none in 156 undisturbed populations. Morphometrics and AFLP markers confirmed that a hybrid swarm existed in a selected disturbed habitat, whereas no intermediates were present where the two species co-occurred in undisturbed vegetation. Individuals of both species in disturbed habitats at 12 sites were more vigorous, with greater size and more flower heads than their counterparts in undisturbed vegetation. These more fecund plants also showed a shift in season and duration of flowering. By promoting earlier flowering of B. hookeriana plants and prolonging flowering of B. prionotes, anthropogenic disturbance broke the phenological barrier between these two species. We conclude that anthropogenic disturbance promotes hybridization through increasing opportunities for gene flow by reducing interpopulation separation, increasing gamete production and, especially, promoting coflowering.


Assuntos
Flores , Hibridização Genética , Proteaceae/genética , Proteaceae/fisiologia , Adaptação Fisiológica , Reprodução , Estações do Ano
6.
Diabetes Care ; 23(9): 1375-80, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10977036

RESUMO

OBJECTIVE: A small percentage of patients do not develop any evidence of diabetic retinopathy (DR) even after many years of diabetes. Vascular endothelial growth factor (VEGF) has been implicated in the development of DR. Therefore, we sought to determine if the regulation of VEGF differs in those patients who develop DR after many years of diabetes compared with those who do not develop DR. RESEARCH DESIGN AND METHODS: We performed standard 7-field stereoscopic fundus photography on 95 consecutive patients with type 1 and type 2 diabetes. Patients were categorized into 3 groups according to the presence or absence of DR and the duration of diabetes: group 1 was defined by presence of DR, group 2 was defined by absence of DR after >10 years duration of diabetes, and group 3 was defined by absence of DR with long-standing diabetes (> or =20 years for type 1 diabetes and > or =15 years for type 2 diabetes). Monocytes from 40 ml peripheral blood were isolated from all patients, and the hypoxic induction of VEGF was determined in vitro. RESULTS: We found no significant difference in the basal level of VEGF in patients with and without DR. However, we did find a markedly significant difference in the hypoxic induction of VEGF between patients from group 1 and group 3 (4.35+/-0.55 vs. 1.87+/-0.3, P<0.00013). CONCLUSIONS: This study suggests that 1 mechanism for the absence of DR in patients with long-standing diabetes is a decreased hypoxic induction of VEGF.


Assuntos
Hipóxia Celular/fisiologia , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Retinopatia Diabética/fisiopatologia , Fatores de Crescimento Endotelial/sangue , Fundo de Olho , Linfocinas/sangue , Monócitos/fisiologia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Fatores de Crescimento Endotelial/biossíntese , Feminino , Humanos , Técnicas In Vitro , Linfocinas/biossíntese , Masculino , Fotografação , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
8.
Int J Sports Med ; 9(5): 345-8, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3246471

RESUMO

Previous research has suggested that psychological factors related to attention and anxiety may identify the injury-prone athlete. In particular, there is some evidence in endurance events that those who utilize a cognitive strategy which associates with sensory feedback pertaining to pace, effort, and fatigue are less likely to be injured. This study investigated the relationship between injury rate and scores on Nideffer's Test of Attentional and Interpersonal Style (TAIS) in 33 elite swimmers resident at the Australian Institute of Sport throughout 1986. The data showed that 56% of the injuries were gradual in onset and resulted from the inability of the swimmer to absorb stress particularly in the upper limbs (overuse). Although these and other intrinsic injuries might theoretically be lower in those with effective internal attentional styles, the data did not support this. Contrary to prediction, the analysis revealed that swimmers with more effective attentional profiles sustained more injuries. Although a number of explanations were offered, the sensitivity of the TAIS to assess appropriate attentional profiles in swimmers was questioned. Future research is suggested which adopts a multidimensional approach in which psychological, physiologic, and situational determinants of injury can be examined. In this way, the contribution of psychological factors to the genesis of swimming injuries can be determined and intervention strategies developed to reduce injury and accelerate recovery.


Assuntos
Traumatismos em Atletas/psicologia , Natação , Adolescente , Adulto , Traumatismos em Atletas/prevenção & controle , Feminino , Humanos , Masculino , Fatores de Risco
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