Pieter Olivier

M.A.P Scientific Services

Species sensitivity to forest fragmentation varies latitudinally, peaking in the tropics. A prominent explanation for this pattern is that historical landscape disturbance at higher latitudes has removed fragmentation-sensitive species or promoted the evolution of more resilient survivors. However, it is unclear whether this so-called extinction fi...

The science guiding design and evaluation of restoration interventions in tropical landscapes is dominated by ecological processes and outcomes and lacks indicators and methods that integrate human wellbeing into the restoration process. We apply a new systems approach framework for tree restoration in forest-agricultural landscapes to show how thi...

Developing innovative monitoring systems for biodiversity outcomes in protected areas (PAs) are important to enable effective adaptive management. Here we show how to quantitatively detect and monitor temporal and spatial patterns in environmental heterogeneity, an important indicator of ecological integrity and biodiversity patterns. We used a 28-...

Global demand for agricultural products continues to grow. However, efforts to boost productivity exacerbate existing pressures on nature, both on farms and in the wider landscape. There is widespread appreciation of the critical need to achieve balance between biodiversity and human well-being in rural tropical crop production landscapes, that are...

Developing innovative monitoring systems for biodiversity outcomes in protected areas (PAs) are important to enable effective adaptive management. Here we show how to quantitatively detect and monitor temporal and spatial patterns in environmental heterogeneity, an important indicator of ecological integrity and biodiversity patterns. We used a 28-...

State‐level conservation in South Africa is structured around distinct political entities (i.e. municipalities). This is problematic because an ecological approach that considers species distribution is required to delineate meaningful management units. To do so, vegetation types can be used as management units—however, it is uncertain whether vert...

Tropical landscapes are changing rapidly due to changes in land use and land management. Being able to predict and monitor land use change impacts on species for conservation or food security concerns requires the use of habitat quality metrics, that are consistent, can be mapped using above-ground sensor data and are relevant for species performan...

Tropical landscapes are changing rapidly due to changes in land use and land management. Being able to predict and monitor land use change impacts on species for conservation or food security concerns requires the use of habitat quality metrics, that are consistent, can be mapped using above - ground sensor data and are relevant for species perform...

Tropical landscapes are changing rapidly due to changes in land use and land management. Being able to predict and monitor land use change impacts on species for conservation or food security concerns requires the use of habitat quality metrics, that are consistent, can be mapped using above - ground sensor data and are relevant for species perform...

[This corrects the article DOI: 10.1371/journal.pone.0173694.].

Questions What drives canopy gap formation in regenerating coastal dune forest? Does canopy gap size‐frequency distribution differ between new‐ and old‐growth forests? Can canopy gaps divert regenerating trajectories?. Location Rehabilitating coastal dune forest in KwaZulu‐Natal, South Africa. Methods We mapped canopy gaps in regenerating dune fo...

ContextEcological theory suggests that large habitat fragments should harbour more species than small fragments. However, this may depend on the surrounding matrix. Matrices in fragmented landscapes may either amplify or reduce area effects, which could influence predicted extinctions based on species-area relationships (SARs). Objective To determi...

Background Canopy structure, defined by leaf area index (LAI), fractional vegetation cover (FCover) and fraction of absorbed photosynthetically active radiation (fAPAR), regulates a wide range of forest functions and ecosystem services. Spatially consistent field-measurements of canopy structure are however lacking, particularly for the tropics. Me...

Changes in structure and functioning of tree communities in response to forest fragmentation may alter tropical forest’s capacity to store carbon and regulate climate. However, evidence for indirect effects of forest fragmentation on above – and belowground carbon pools through changes in forest biodiversity is scarce. Here we focus on understandin...

Forest edges influence more than half of the world's forests and contribute to worldwide declines in biodiversity and ecosystem functions. However, predicting these declines is challenging in heterogeneous fragmented landscapes. Here we assembled a global dataset on species responses to fragmentation and developed a statistical approach for quantif...

The peninsula effect predicts that the number of species should decline from the base of a peninsula to the tip. However, evidence for the peninsula effect is ambiguous, as different analytical methods, study taxa, and variations in local habitat or regional climatic conditions influence conclusions on its presence. We address this uncertainty by u...

This file contains the data from the article “Pattern or process? Evaluating the peninsula effect as a determinant of species richness in coastal dune forests” by Pieter I. Olivier, Victor Rolo, and Rudi J. van Aarde. (CSV)

Functional diversity indicators are increasingly used to monitor forest function recovery because they connect biodiversity to ecosystem functions. However, identifying which functions deviate from a reference forest has not received much attention, despite its potential to inform restoration interventions. In this study, we used functional groups...

South African coastal forests form part of two critically endangered eco-regions and harbor an extinction debt. Remaining fragments are small, isolated, and embedded within a range of human land-use types. In this study, we ask: how should we invest conservation resources if we want to restore this landscape and prevent predicted extinctions? To an...

The planting or seeding of pioneer species to promote restoration apparently contributes little to the establishment of late-successional species, despite the common assumption that they facilitate forest regeneration. We evaluate the consequences of planting pioneers for coastal dune restoration by measuring plant traits (specific leaf area, wood...

Questions Can trends derived from chronosequences (space) be compared with those derived from repeated surveys (time) to validate the use of space-for-time substitution? Can this approach provide insight into the dynamics of vegetation in rehabilitating forests? Location Rehabilitating coastal dune forest in KwaZulu-Natal, South Africa. Methods...

Coastal ecosystems are centres of high biological productivity, but their conservation is often threatened by numerous and complex environmental factors. Citing examples from the major littoral habitats worldwide, such as sandy beaches, salt marshes and mangrove swamps, this text characterises the biodiversity of coastline environments and highligh...

Aim We used a hierarchical fractal‐based sampling design to test how sampling grain influences (1) beta diversity of and (2) inferences from the modelled contribution of niche‐ versus dispersal‐based assembly processes in structuring tree and bird assemblages. Location Coastal forest fragments, South Africa. Methods We surveyed 103 tree plots and...

Aim Predicting extinctions before they are realized has proven difficult, yet is increasingly important for biodiversity conservation as habitat destruction continues unabated around the world. We evaluated whether habitat suitability models can be used in conjunction with species–area relationships ( SAR ) to detect apparent extinction debts as im...

We used dung surveys to estimate population size and extracted an age structure from boli diameters for the elephants living in the Maputo Elephant Reserve. Our estimate was based on published defecation rates, dung decay rates, distance-sampling techniques and 1,672 dung piles encountered on 204 line-transects. The reserve had at least 311 (95% CI...

The metapopulation metaphor is increasingly used to explain the spatial dynamics of animal populations. However, metapopulation structure is difficult to identify in long‐lived species that are widely distributed in stochastic environments, where they can resist extinctions. The literature on mammals may not provide supporting evidence for classic...

T HE PREVAILING INCREASE IN ELEPHANT numbers across areas of southern Africa raises concern for their impact on biological diversity. Several approaches to elephant management focus on limiting numbers to alleviate these consequences. However, landscape fragmentation, fences, water supple-mentation as well as the shape and size of some conservation...