Disturbance Ecology

Fires have been important in the Klamath-Siskiyou for millennia.  Where burn severities are mixed, as they are in much of the Klamath-Siskiyou, fires may be instrumental in creating landscape heterogeneity.  Landscape heterogeneity is linked to structural and taxonomic diversity, for which the Klamath-Siskiyou region is renowned.  We recently analyzed spatial patterns of fire severity in a 98,814 ha area burned in 1987 to evaluate
the role of fire in creating landscape diversity. The study area was in the Marble and Trinity Mountains area, which is dominated by Douglas-fir and tanoak forests.  We found that fire severity was mostly low (59% of the area), but that patchy high severity fire (12% percent of the area) also occurred.  In forests and sclerophyll vegetation where fire had been previously absent for many decades less high severity fire was found, whereas those that had burned previously in prior decades had more high severity fire.  Therefore, the length of fire-free intervals can influence the production of high severity patches in
the landscape.  Fire interval may also determine the persistence of these patches, which return to forest vegetation following many decades without stand-replacing fire.  The high degree of spatial and temporal variation in fire in our study area results in a landscape of complex and dynamic patches of differing ages.  Patch dynamics differ in landscapes containing even-aged plantations.  We found these burned with twice the
severity of closed forests.  Positive feedback between plantations and fire, and the persistence of plantations over fire intervals of any length favor the filling in of
landscapes with structurally and biologically simplified vegetation.

Těžba, či ponechání jedinců smrku ztepilého zasažených gradací lýkožrouta smrkového v národním parku Šumava je předmětem neutuchajících diskusí. Téma Šumavy vytváří kulisu pro podstatnou část disputací na poli ochrany přírody. Převážná část lesnické obce zastává, zjednodušeně řečeno, tento názor: „Na Šumavě rostou uměle vzniklé monokultury smrku, nezřídka pochybné provenience, přičemž přirozeně by se zde na většině území vyskytovaly smíšené lesy. Ony nepůvodní monokultury byly ponechány působení kůrovce, jenž zelené lesy změnil v mrtvé porosty na úkor prospěšných funkcí, ne-li samotné podstaty existence lesa. Správným postupem by přitom byla včasná těžba a asanace větrem vyvrácených či kůrovcem napadených smrků, tak aby se lýkožrout nemohl šířit, se souběžnou přeměnou porostů na les přirozené dřevinné skladby (s jedlí a bukem).“

The spider fauna of Barangay Sinaloc, in El Salvador City was sampled from three cites (A, B and C) to assess the relative abundance, species diversity, evenness and their habitat preferences. A total of 187 individuals were collected from three families and nine genera. Most of the species collected came from the family Araneidae, with the two most dominant species being Araneus inustus L. Koch, 1871 and Gasteracantha clavigera Giebel, 1863. The majority of the collected spiders were from Site C, the least disturbed ecosystem. Overall, the species were variably distributed and with a moderate level of species diversity (H1 = 1.68). Spider species from Araneidae and Theridiidae preferred Site C as its habitat over the two other sites because it offers larger space for web construction in bushes and herbs, and because it is the least disturbed site. Several spider species collected did not show habitat preference because there was no significant difference in their distribution in the three sites sampled. Based on evidence from the collected data, Barangay Sinaloc in El Salvador City can still support spider life and diversity but regular follow-up studies must be conducted to further assess the condition of spider fauna.

In recent years, there has been a rethinking of the role of disturbance regimes in nature conservation: from exceptional and destructive events to be controlled and/or avoided, to key ecological processes to be nurtured and choreographed. These regimes concern the spatiotemporal dynamics of ecological disturbances, understood here as events that disrupt the structure of an ecology, community or population, causing profound changes in an ecosystem. The rethinking of their role precedes but resonates with current enthusiasms for proactive and experimental modes of conservation, such as rewilding.
This thesis draws on three case studies (the New Forest, Knepp Castle Estate and Dundreggan Estate) to explore the ontological, epistemic and socio-political implications of rewilding for the governance of forest disturbance regimes in the UK, particularly through the use of large herbivores. Drawing upon relational understandings of nature, space and time, it develops an understanding of disturbance regimes as process and practice. It first examines how rewilding departs from orthodox biopolitical modes of governing life and the ontological politics at the interface between these various modes. To this end, it attends to the ways in which disturbances have been historically understood and how these understandings have come to shape their governance. Second, it explores the knowledge practices through which ecologists and forest managers know and enact disturbances, comparing a traditional ‘prescriptive’ approach with rewilding. It argues that in practice rewilding is multiple, in contrast to rewilding discourse. Finally, it maps the different and sometimes conflicting social, economic and cultural values associated with working with natural processes, exploring the political ecologies of governing disturbance regimes. It argues that controversies around forest management pertain to a large extent to contrasting perceptions of different types of ‘work’ within the idea of working landscape and how they are ‘naturalised’.
In the conclusion, the thesis explores three empirical and conceptual contributions of these findings for those seeking to understand the logics of rewilding and the processes, practices and dynamics by which nonhuman forms and processes are governed in a post-Natural and uncertain future. First, by deploying a relational approach to the governance of disturbance regimes and by focusing on a long-term disturbance, I draw out the relevance of temporality for thinking through and with disturbances as social and ecological processes. Second, by drawing attention to the intertwining of bio- and socio-political regimes, I propose a reframing of (European) rewilded landscapes as working landscapes. Finally, by attending to the intricacies of practice, I argue that rewilding praxis is multiple and hybrid. It often involves compromises and is shaped by past governance histories and the broader political and social context.

Human activity during the Anthropocene has transformed landscapes worldwide on a scale that rivals or exceeds even the largest of natural forces. Landscape ecology has emerged as a science to investigate the interactions between natural and anthropogenic landscapes and ecological processes across a wide range of scales and systems: from the effects of habitat or resource distributions on the individual movements, gene flow, and population dynamics of plants and animals; to the human alteration of landscapes affecting the structure of biological communities and the functioning of entire ecosystems; to the sustainable management of natural resources and the ecosystem goods and services upon which society depends. This novel and comprehensive text presents the principles, theory, methods, and applications of landscape ecology in an engaging and accessible format that is supplemented by numerous examples and case studies from a variety of systems, including freshwater and marine "scapes".

Essentials of Landscape Ecology is suitable for upper-level undergraduate and graduate courses in landscape ecology. This textbook can also be used as a supplemental text in other ecology courses, as well as courses in forestry, resource and wildlife management, conservation and restoration biology, sustainable land-use and environmental planning.  For the professional landscape ecologist, it provides an authoritative overview of the latest research and developments.

Available through all major booksellers or directly from Oxford University Press:
https://global.oup.com/academic/product/essentials-of-landscape-ecology-9780198838388

A B S T R A C T Changes in land-use and climate increase the flammability of forests across southeast Amazonia, potentially driving abrupt fire-mediated transitions to derived savannas – grass-dominated degraded forests with scattered trees. However, the extent to which the forest fauna undergoes a parallel process remains poorly understood. Here we test the hypothesis that the process of fire-driven forest shifts towards derived savannas has congruent cascading effects on ant communities by causing declines in forest specialists and an influx of open-habitat taxa. In 2013 we collected ants using subterranean, epigaeic and arboreal pitfall traps in three adjacent 50-ha plots: an unburnt control and two treatment plots that were burnt either triennially or annually from 2004 to 2010. Frequent fire was associated with a marked decline of specialist forest species (almost 50%), and an influx of open-habitat taxa that were absent from the unburnt plot. The effects were particularly pronounced for epigaeic ants: their abundance, biomass, species richness and species composition were impacted by fires, and this was the main stratum occupied by the open-habitat species. Previous studies have shown that a similar conversion is not triggered by single fires, and they therefore require recurrent fires. Our results provide experimental evidence that the process of tropical forest conversion towards derived savannas caused by repeated burning is a broad one that affects not only plants, but involves parallel compositional shifts of animal communities. The prevention of recurrent fires is a priority challenge for avoiding widespread biotic conversion of tropical forests to derived savannas.

This review considers factors affecting the flight capacity of carabid beetles and the implications of flight for carabids. Studies from the Dutch polders in particular show that young populations of carabids consist predominantly of macropterous species and macropterous individuals of wing-dimorphic species. Also populations of wing-dimorphic carabid species at the periphery of their geographical range contain high proportions of macropterous individuals. However, studies from Baltic archipelagos show that older populations of even highly isolated island habitats contain considerable proportions of brachypterous species and individuals. This suggests that macroptery is primarily an adaptation for dispersal and that there exists a mechanism for subsequently reducing the ratio of macropterous to brachypterous species under stable conditions, due to the competitive advantage
of brachyptery. Populations in isolated habitats, such as islands and mountains, have high proportions of brachypterous species. Many macropterous species do not possess functional flight muscles. Species of unstable habitats, such as tree canopies and wet habitats, are mostly macropterous. Brachypterous species tend to disappear from disturbed habitats. There is uncertainty regarding the extent to which carabid dispersal is directed and how much passive. Both Den Boer and Lindroth recognized that mostly macropterous individuals of macropterous and wing-dimorphic species disperse and found new populations, after which brachyptery tends to rapidly appear and proliferate in the newly founded population. It is most likely that the allele for brachyptery would
arrive via the dispersal of gravid females which had mated with brachypterous males prior to emigration. Whilst many studies consider wing morphology traits of carabid beetles to be species-specific and permanent, a number of studies have shown that the oogenesis flight syndrome, whereby females undertake migration and subsequently lose their flight muscles by histolysis before eventually regenerating them after reproducing, has been reported for a growing number of carabid species. Wing morphology of carabid beetles clearly offers strong potential for the study of population dynamics. This field of study flourished during the 1940’s to the late 1980’s. Whilst a considerable amount of valuable research has been performed and published, the topic clearly holds considerable potential for future study.

Understanding how anthropogenic disturbance influences patterns of community composition and the reinforcing interactive processes that structure communities is important to mitigate threats to biodiversity. Competition is considered a primary reinforcing process, yet little is known concerning disturbance effects on competitive interaction networks. We examined how differences in ant community composition between undisturbed and disturbed Bornean rainforest, is potentially reflected by changes in competitive interactions over a food resource. Comparing 10 primary forest sites to 10 in selectively-logged forest, we found higher genus richness and diversity in the primary forest, with 18.5% and 13.0% of genera endemic to primary and logged respectively. From 180 hours of filming bait cards, we assessed ant-ant interactions, finding that despite considered aggression over food sources, the majority of ant interactions were neutral. Proportion of competitive interactions at bait cards did not differ between forest type, however, the rate and per capita number of competitive interactions was significantly lower in logged forest. Furthermore, the majority of genera showed large changes in aggression-score with often inverse relationships to their occupancy rank. This provides evidence of a shuffled competitive network, and these unexpected changes in aggressive relationships could be considered a type of competitive network re-wiring after disturbance.

In this piece I consider emptiness as a consequence of war. War creates and leaves behind a particular form of emptiness—deadly environments contaminated with military waste. BiH is the country most heavily contaminated with military waste in Europe. Despite much progress in clearance, over 0.5 million people in nearly 1,400 local communities are still living around such deadly environments/ located mainly in rural areas, where the levels of contamination are particularly high for forested and agricultural land. Deadly environments are uncanny timespaces of late modernity. They might have been emptied of humans and littered with military waste as consequences of modern warfare. But these human-induced disturbances might also initiate new stories and sediments of life.

The survey and continuing inventory in the Bavarian Forest National Park of deadwood areas resulting from a spruce bark beetle calamity are being performed by means of visual evaluation of colour infrared aerial photographs. With the aid of the object-oriented image analysis software eCognition, it was possible to develop a partially automated method for this purpose. In order to verify the classification results, a test area was classified, and the results compared with those obtained by the previously used method. In addition, the classification results from two consecutive years were compared, and accuracy assessment methods were used to scrutinize the results. Classification in the deadwood areas yielded a total classification accuracy of 91.5%. In regard to objectivity and degree of detail, the newly developed method is significantly superior to the former method, which is based on visual interpretation with a stereo workstation. One problem, however, was the insufficient spatial accuracy of the respective orthophotos. Because of this, it was not possible to detect changes over the course of specified time intervals. Therefore, a practical application of this method would require that the orthophotos from various dates or times be precisely spatially assigned. This requirement can be achieved with the production of new orthophotos.

Hemeroby is an indicator widely used in plant ecology that indicates the level of disturbance of the optimal habitat for a species. Hemeroby is scaled on a range of ten or five point scores, higher scores of hemeroby meaning higher level of disturbance. In this paper, we introduced two metrics of hemeroby: the species hemeroby score (HS), as a proxy for the suitability to specific disturbed habitats, and hemerobiotic diversity (H’H), as a proxy for species generalism, this last synthesizing the numbers and frequency of habitats of different hemeroby where a species occurs. We related HS and H’H of 75 common breeding bird species to their regional range of occupancy in Latium (central Italy). H’H is positively correlated with regional range of occupancy. Grouping data in categories, we observed a significant trend in regional range of occupancy, increasing from species with low H’H (i.e. specialized) to species with progressively higher H’H (i.e. generalists). nevertheless, only the ...

This paper is a literature review of multiple and intersecting drivers and hypotheses regarding the failure of oak regeneration in eastern deciduous forests of the eastern United States  Below, is the introduction to the review.  It is an interesting story to me that reads somewhat as an ecological mystery.

Over the past few decades, a concern has been growing among foresters and ecologists that many Quercus species across the eastern deciduous forests have been declining in relative dominance (Fei et al., 2011) and that they are not regenerating as frequently or quickly as other more shade tolerant species (Abrams and Downs, 1990; Alexander et al., 2008; Blankenship and Arthur, 2006).  Evidence documenting this decline has been quantified from forests across the eastern United States on all scales from gap studies (Rentch et al. 2003, Hart and Kupfer, 2011) to regional studies (Fei et al., 2011).  While uncertainty persists regarding the interacting causes of this whole cloth change in our forest ecosystems, research and management decisions are daily being made to better understand the ecological drivers of this widespread alteration, what stages in the lifecycle of trees might be most sensitive to silvicultural treatments (Brose and Van Lear, 1998;  Arthur et al., 2012) and/or disturbance both natural (Martin et al., 2012; Arthur et al., 2012) or anthropogenic in origin (Roberts and Gilliam, 1995).  The management objective becomes identifying how the balance might be tipped in favor of reliably restoring oak stands across the eastern United States (Martin et al., 2011; Schweitzer and Dey, 2011).  The uncertainty about what is causing the incremental successional change persists partially as a function of the long life spans of trees in general, but also because the cumulative changes in land use over the past couple hundred years have been dramatic and relentless - multiple, cumulative and sometimes overlapping changes caused by the efforts of Euro-Americans to maximize resource extraction for the benefit of exponentially growing populations in the New World.
As resource extraction and subsequent abandonment of land or shifts in land use for other economic activities continue, the ecological sciences are involved in teasing apart and documenting some of the drivers of this change so that society-at-large, given a socioeconomic / political choice, can decide to restore the measurable forest function or to at least minimize and mitigate some of the more deleterious impacts.  Add to the mix of interacting ecological drivers in forest function and succession the ramifications of global climate change, polluted streams and watersheds, acid rain, population changes in other native mammalian species, and the unexpected ravages of some novel introduced plant, animal, insect pest, and/or microbial species and the questions and concerns multiply.  For example, many Lumbricidae species of earthworms are having a great feast in formerly glaciated forest regions in the northern United States where they accelerate the fundamental decomposition processes and therefore, nutrient cycling rates (Szlavecz et al., 2006; Tuinov et al., 2006).  Considering just a few of the uncertainties interwoven with the fates of our eastern deciduous forests and our need for forest products, and it is justifiable that foresters and ecologists and other concerned citizens sound an alarm that more research into the multifarious factors, biotic and abiotic, should and can be done so that we may develop more predictable outcomes from forest management techniques over the coming decades and centuries.
People every day are using the forest whether it is a simple stroll through the woods, designing new housing projects adjacent to public lands, making plans for the next timber sale or altering watercourses.  Therefore, on the heels of ecological science comes the infancy of restoration science which typically must address the multiple needs and desires of people using the forest (Bradshaw 1987; Leopold, 1949).  For example, ecological sciences become essential to inform new debates about how to manage stands for sustainable productivity, protect watersheds, restore wild turkey populations, set limits on hunting for deer, treat pesky Rosa multiflora infestations, and protect the properties of landowners bordering parks from wildfire.  Because ecosystems tend to repair themselves much slower than damage can be inflicted upon them, it seems incumbent that foresters, wildlife managers, restoration ecologists and perceptive backyard gardeners all be well-educated about ecological principles so that we may make wiser, more thoughtful decisions about our land use.
I take the fate of Quercus species in the eastern deciduous forests as the main subject of this manuscript.  This paper will survey some of the literature that 1) documents the decline of oak regeneration, 2) partially reconstructs the landscapes of millennial-past eastern United States forests 3) identifies and details some of the important drivers of forest regeneration and succession, and 4) experimentally tests various interacting mechanisms correlated with the decline in oak regeneration across an array of temporal and spatial scales.  Finally, I will discuss how the results and conclusions from these various studies inform a new paradigm of adaptive management that will 1) require the continued refinement of silvicultural and other treatments on forest land, 2) invite the participation of interdisciplinary research, 3) foster the best practices by restoration ecologists and 4) educate the public about ecological science and how that can translate to improved land use activities by all people.

Courir, marcher, ramper, galoper, ou simplement contempler sont des activités de plein air indispensables au bien-être de chaque humain. Sur une terre où la nature laisse la place à l'urbanisation, à des structures de transport, à l'agriculture, les surfaces utilisables pour ces activités de plein air se réduisent et la pression augmente sans cesse sur la faune, la flore, les milieux naturels. Quelques conseils de bon sens permettent de pratiquer son activité dans le plus grand respect de ce patrimoine naturel. Ce guide est une invitation à un comportement respectueux et dont l'adoption permettra de conserver la nature sans avoir à la mettre sous cloche.

Physical disturbances of the seafloor play a key role in ecosystem function and are postulated to exert control over spatial patterns of biodiversity.  This review investigates the role of natural physical sedimentological processes that occur in shelf, slope and abyssal environments that also act as disturbances to benthic ecosystems and which, under certain circumstances, give rise to benthic disturbance regimes.  Physical sedimentological processes can cause both press (process that causes a disturbance by acting over a timespan that is intolerable to benthos) and pulse (process that causes a disturbance by exceeding a threshold above which benthos are unable to remain attached to the seabed or are buried under rapidly deposited sediment) types of disturbance.  On the continental shelf, pulse-type disturbances are due to temperate and tropical storm events, and press-type of disturbances identified here are due to the migration of bedforms and other sand bodies, and sustained periods of elevated turbidity caused by seasonally reversing wind patterns.  On the continental slope and at abyssal depths, pulse-type disturbances are due to slumps, turbidity currents; benthic storms may cause either press or pulse type disturbances.  A possible press-type of disturbance identified here is inter-annual changes in abyssal bottom current speed and/or direction.  It is concluded that: 1) physical sedimentary disturbance regimes may characterize as much as 10% of the global ocean floor; 2) multidisciplinary research programs that integrate oceanography, sedimentology and benthic ecology to collect time series observational data sets are needed to study disturbance regimes; and 3) predictive habitat suitability modeling must include disturbance regime concepts, along with other biophysical variables that define the fundamental niches of marine species, in order to advance.

The sea star Parvulastra parvivipara is a small range endemic known from only seven granitic headlands in South Australia. Evidence from previous studies suggests that its unstable boulder habitat will experience increased disturbance as sea levels rise. This study investigated distributional and ontogenetic patterns of P. parvivipara across different sized boulders that vary in physical stability and susceptibility to disturbance. To develop a better understanding of community dynamics in P. parvivipara habitat, patterns were also assessed for a chiton that the sea star commonly co-occurs with (Ischnochiton variegatus), and assemblages of encrusting species were also measured, as these can vary amongst boulder sizes and influence mobile animals. Large boulders had many tubeworms, contributing to a significant boulder-size effect on encrusting species assemblage structure. P. parvivipara was most abundant on the smallest boulders; there was no evidence that abundances were influenced by encrusters. I. variegatus abundances were unaffected by boulder size, but a positive correlation between lengths of individuals and encruster cover occurred on the smallest boulders. Overall, physical habitat features, not encrusting biota, likely caused an association of P. parvivipara with small boulders, while I. variegatus displayed apparent ontogenetic use of encruster-related habitat features. As P. parvivipara uses mostly small boulders that are particularly susceptible to disturbances which are increasing with rising sea levels, future ecological restoration efforts to protect this rare species may be required, which can be properly informed about necessary habitat requirements from these results.

In this thesis I use carabid beetles (Coleoptera, Carabidae) and vascular plants to investigate the ecological effects of urbanization on forested and dry meadow habitats in the city of Helsinki, Finland. I also investigate factors that affect species
diversity and the occurrence of rare and sensitive species in particular, in order to draft recommendations for habitat management for the enhancement of urban biodiversity. Urbanization gradient analyses are conducted using multivariate ordination analyses to elucidate assemblage level responses, ANOVA is applied to determine the assemblage level response of spruce forest carabid assemblages and GLMM is used to model individual species responses. The results suggest that, in contrast to Gray’s suggestion, Preston’s log-normal does not accurately describe the species distributions of carabid beetles in the studied habitats but rather they follow the predictions of Fisher’s log series and Hubbell’s unified neutral theory. I conclude that fragmentation, isolation and homogenization are the main problems regarding maintenance of urban biodiversity, and that biodiversity strategies should focus on the conservation of stenotopic species. In particular, habitats and ecologically important microhabitat conditions should be retained in as large and contiguous a form as possible. For instance, spruce forest habitats need to be managed to maintain shady, cool and moist conditions and dry meadows should be mown late in the season and the cut vegetation removed. Additionally, supplementation of habitat
networks should be implemented, by habitat restoration and habitat creation, such as the construction of dry meadows on landfills and noise abatement banks.

Natural disturbances play a key role in ecosystem dynamics and are important factors for sustainable forest ecosystem management. Quantitative models are frequently employed to tackle the complexities associated with disturbance processes. Here we review the wide variety of approaches to modelling natural disturbances in forest ecosystems, addressing the full spectrum of disturbance modelling from single events to integrated disturbance regimes. We applied a general, process-based framework founded in disturbance ecology to analyze modelling approaches for drought, wind, forest fires, insect pests and ungulate browsing. Modelling approaches were reviewed by disturbance agent and mechanism, and a set of general disturbance modelling concepts was deduced. We found that although the number of disturbance modelling approaches emerging over the last 15 years has increased strongly, statistical concepts for descriptive modelling are still largely prevalent over mechanistic concepts for ex...

Ecological thresholds represent a critical tipping point along an environmental gradient that, once breached, can have irreversible consequences for species persistence and assemblage structure. Thresholds can also be used to identify species with the greatest sensitivity to environmental changes. Bats are keystone species yet are under pressure from human disturbances, specifically landscape and cave disturbances (i.e., reduced forest cover, urbanization, hunting, tourism). We compared bat assemblages across environmental and disturbance gradients measured at 56 caves in the Philippines to identify species-specific thresholds and assess congruence among species responses. All species exhibited significant responses to one or more gradients, with 84% responding to more than one gradient. Yet mixed responses of sensitivity to some gradients but tolerance to others hindered identification of assemblage thresholds to all gradients except landscape disturbance. However, we identified credible indicator species that exhibit distinct thresholds to specific gradients and tested for differences in ecological and morphological traits between species groups with shared responses (i.e., negative or positive). Few traits were useful for discriminating the direction of a species response, with some exceptions. Species that responded positively to increased landscape disturbance and hunting had greater body mass, whereas species that responded negatively to mining emitted higher peak call frequencies.

Remote mountainous regions are among the Earth’s last remaining wild spots, hosting rare ecosystems and rich biodiversity. Because of access difficulties and low population density, baseline information about natural and human-induced disturbances in these regions is often limited or nonexistent. Landsat time series offer invaluable opportunities
to reconstruct past land cover changes. However, the applicability of this approach strongly depends on the availability of good quality, cloud-free images, acquired at a regular time interval, which in mountainous regions are often difficult to find. The present study analyzed burn scar detection capabilities of 11 widely used spectral indices (SI) at 1 to 5 years after fire events in four dominant vegetation groups in a mountainous region of northwest Yunnan, China. To evaluate
their performances, we used M-statistic as a burned-unburned class separability index, and we adapted an existing metric to quantify the SI
residual burn signal at post-fire dates compared to the maximum severity recorded soon after the fire. Our results show that Normalized Burn Ratio (NBR) and Normalized Difference Moisture Index (NDMI) are always among the three best performers for the detection of burn scars starting 1 year after fire but not for the immediate post-fire assessment, where the Mid Infrared Burn Index, Burn Area Index, and Tasseled Cap Greenness were superior. Brightness and Wetness peculiar patterns revealed long-term effects of fire in vegetated land, suggesting their potential integration to assist other SI in burned area detection several years after the fire event. However, in general, class separability of most of the SI was poor after one growing season, due to the seasonal rains and the relatively fast regrowth rate of shrubs and grasses, confirming the difficulty of assessment in mountainous ecosystems. Our findings are meaningful for the selection of a suitable SI to integrate in burned area detection workflows, according to vegetation type and time lag between image acquisitions.

As attention to resilience grows, debates in geography have focused on the relationship between resilience and vulnerability. This discussion raises further questions that geographers may be well positioned to address: what can be done in contexts where vulnerability is desirable, or where resilience is undesirable and where innovation may be called for? Many undesirable systems are resilient, yet strategies to break resilience down and promote innovation are not often discussed. Building on perspectives from human and physical geography, we present a new hypothesis about the relationship between disturbance and innovation. This disturbance innovation hypothesis states that low and high levels of disturbance are associated with the highest levels of innovation while intermediate levels of disturbance are associated with the lowest levels of innovation. By integrating broad perspectives from geography and its related fields, we hope to spur discussion surrounding unwanted resilience, barriers to reform, and strategies for transformation.

The ultimate determinants of cathemerality, i.e., activity spread over the 24-h cycle, in primates have been linked to various ecological factors. Owing to the fast rate of habitat modification, it is imperative to know whether and how this behavioral flexibility responds to anthropogenic disturbance. The true lemurs (Eulemur clade) constitute a valuable case to study these potential effects, as all species studied so far exhibit cathemerality. Here we explored the effects of anthropogenic disturbance on activity patterns of Eulemur while controlling for ecological factors proposed as determinants of activity shifts. We first performed a meta-analysis using 13 long-term studies conducted over the last three decades on various populations of Eulemur. We fitted a beta regression using the proportion of diurnality (the activity taking place between sunrise and sunset) as the response variable and seven climatic, ecological, and anthropogenic disturbance variables at each site as predictors. We also present a validation with original data using year-round, 24-h activity of collared brown lemurs (Eulemur collaris) in forest fragments with different levels of disturbance in southeastern Madagascar. Diurnality was prevalent at most sites. Seasonality, proportions of leaves in the diet, and group size were all found to be significant predictors of the proportion of diurnal activity. After controlling for socioecological factors in the model, overall anthropogenic disturbance emerged as a negative predictor of diurnality. Our validation suggests that the lemurs in the more disturbed area exhibited more nocturnal activity than those in the less disturbed area. It is unclear whether the plasticity Int J Primatol

Despite forests are a biodiversity reservoir and a wellbeing source for the humankind, they have been largely disturbed in the past decades. Disturbed and naturally-regenerated forests and forest plantations represent 75% of the world forested area, stressing the need of managing non-pristine forests. While we know that habitat disturbance alters forest structure, reducing species richness and abundances, its effects on animal behavior remain little explored. We used camera traps to test if daily activity patterns of forest birds change along a 450-km disturbance gradient in the Valdivian temperate rainforests of southern Chile. We contrasted bird activity at four conditions: old-growth and second-growth native forests, native forests subject to selective logging, and abandoned exotic plantations with native vegetation. We contrasted habitat structure among conditions and estimated activity kernels to compare bird activity. We also made activity comparisons examining bird foraging guilds (nectarivores, frugivores, and insectivores) and habitat preference (interior vs edge). Habitat structure was different among conditions, being the old-growth native stands the most contrasting habitat. Bird daily activity patterns differed among conditions as well. We observed that bird activity reaches a peak early in the morning at the old-growth native forests, at noon in the plantations, and in the afternoon at the logged forests, while it was more variable in secondary forests. We obtained similar results among bird foraging guilds, but insectivorous birds presented the most contrasting differences. Likewise, we found a similar pattern between forest interior and edge species, which was more evident for forest interior birds. Logged forests presented the largest activity differences, despite being structurally similar to second-growth stands. Forest disturbance not only alters bird species richness and abundance, but also their behavior. Bird daily activity patterns may be directly affected by daily variations in forest microclimate conditions and indirectly affected by chantes in resource availability, which may be affecting their ecological interactions. Therefore, forest management and restoration strategies should take animal behavior into account.

Pest and pathogen disturbances are ubiquitous across forest ecosystems, im-pacting their species composition, structure, and function. Whereas severe abiotic disturbances (e.g., clear-cutting and fire) largely reset successional trajectories, pest and pathogen disturbances cause diffuse mortality, driving forests into nonanalogous system states. Biotic perturbations that disrupt forest carbon dynamics either reduce or enhance net primary production (NPP) and carbon storage, depending on pathogen type. Relative to defolia-tors, wood borers and invasive pests have the largest negative impact on NPP and the longest recovery time. Forest diversity is an important contributing factor to productivity: NPP is neutral, marginally enhanced, or reduced in high-diversity stands in which a small portion of the canopy is affected (temperate deciduous or mixed forests) but very negative in low-diversity stands in which a large portion of the canopy is affected (western US forests). Pests and pathogens reduce forest structural and functional redundancy, affecting their resilience to future climate change or new outbreaks. Therefore, pests and pathogens can be considered biotic forcing agents capable of causing consequences of similar magnitude to climate forcing factors.

Cyclones, which change tree communities and alter forest structure, are thought to have had a significant selective pressure on the flora and fauna of Madagascar. Very little information, however, is available on the actual impact of cyclones on Malagasy ecosystems. On 21 January 2009, Cyclone Fanele made landfall on the western coast of Madagascar with sustained winds of 185 km/h. We examined the immediate effects of the cyclone on tropical dry forest structure in the Kirindy Mitea National Park. In July and August 2009, we measured the height, diameter at breast height (dbh), and damage for 1361 trees in nine 25 × 25 m plots. We found that: (1) over 95 percent of trees experienced some sort of damage, including 8.8 percent mortality; (2) understory and emergent trees experienced significantly higher mortality than canopy trees; and (3) stem density was reduced 9.2±4.5 percent and biomass was reduced 13.4±8.1 percent after the cyclone. Dbh was the best predictor of trunk damage and mortality. This extensive alteration of forest structure will have a substantial short- and long-term impact on the biotic communities of western Madagascar.