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Do United States protected areas effectively conserve forest tree rarity and evolutionary distinctiveness?
... The indicators described in this report encompass forest insect and disease activity, wildland fire occurrence, drought, tree mortality, and vegetation phenology change, among others. The previous reports in this series are Ambrose and Conkling (2007, 2009), Conkling (2011, Conkling and others (2005), Coulston and others (2005aCoulston and others ( , 2005bCoulston and others ( , 2005c, and Potter and Conkling (2012a, 2012b, 2013a, 2013b, 2015a, 2015b, 2018, 2019. Visit https://www.fs.fed.us/foresthealth/ ...
... publications/fhm/fhm-publications.shtml). The emphases of these publications include forest health data (Potter and others 2016, Siry and others 2018, Smith and Conkling 2004; soils as an indicator of forest health (O'Neill and others 2005); urban forest health monitoring (Bigsby and others 2014;others 2006, 2007;Lake and others 2006); remote sensing of forest disturbances (Chastain andothers 2015, Rebbeck andothers 2015); health conditions in national forests (Morin and others 2006); crown conditions (Morin and others 2015;Randolph 2010aRandolph , 2010bRandolph , 2013Randolph and Moser 2009;Schomaker and others 2007); indicators of regeneration (McWilliams and others 2015); vegetation diversity and structure (Schulz and Gray 2013, Schulz and others 2009, Simkin and others 2016; forest lichen communities others 2012, Root andothers 2014); downed woody materials in forests others 2012, 2013); drought (Vose and others 2016); ozone monitoring (Rose and Coulston 2009); patterns of nonnative invasive plant occurrence others 2015, 2017;Iannone and others 2015Iannone and others , 2016aIannone and others , 2016bIannone and others , 2018Jo and others 2018;Oswalt and others 2015;Riitters andothers 2018a, 2018b); assessments of forest risk or tree species vulnerability to exotic invasive forest insects and diseases others 2011, 2014;Krist and others 2014;Potter andothers 2019a, 2019b;Vogt and Koch 2016;Yemshanov and others 2014); spatial patterns of landcover and forest fragmentation (Guo and others 2018;Riitters 2011;Riitters and Costanza 2018;Riitters and others 2012Riitters and others , 2016Riitters and others , 2017; impacts of deer browse on forest structure (Russell and others 2017); broad-scale assessments of forest biodiversity (Guo and others 2019;Potter 2018;Potter and Koch 2014;Potter andWoodall 2012, 2014); predictions and indicators of climate change effects on forests and forest tree species (Fei and others 2017, Heath and others 2015, Potter and Hargrove 2013; and the overall forest health indicator program (Woodall and others 2010). ...
... publications/fhm/fhm-publications.shtml). The emphases of these publications include forest health data (Potter and others 2016, Siry and others 2018, Smith and Conkling 2004; soils as an indicator of forest health (O'Neill and others 2005); urban forest health monitoring (Bigsby and others 2014;others 2006, 2007;Lake and others 2006); remote sensing of forest disturbances (Chastain andothers 2015, Rebbeck andothers 2015); health conditions in national forests (Morin and others 2006); crown conditions (Morin and others 2015;Randolph 2010aRandolph , 2010bRandolph , 2013Randolph and Moser 2009;Schomaker and others 2007); indicators of regeneration (McWilliams and others 2015); vegetation diversity and structure (Schulz and Gray 2013, Schulz and others 2009, Simkin and others 2016; forest lichen communities others 2012, Root andothers 2014); downed woody materials in forests others 2012, 2013); drought (Vose and others 2016); ozone monitoring (Rose and Coulston 2009); patterns of nonnative invasive plant occurrence others 2015, 2017;Iannone and others 2015Iannone and others , 2016aIannone and others , 2016bIannone and others , 2018Jo and others 2018;Oswalt and others 2015;Riitters andothers 2018a, 2018b); assessments of forest risk or tree species vulnerability to exotic invasive forest insects and diseases others 2011, 2014;Krist and others 2014;Potter andothers 2019a, 2019b;Vogt and Koch 2016;Yemshanov and others 2014); spatial patterns of landcover and forest fragmentation (Guo and others 2018;Riitters 2011;Riitters and Costanza 2018;Riitters and others 2012Riitters and others , 2016Riitters and others , 2017; impacts of deer browse on forest structure (Russell and others 2017); broad-scale assessments of forest biodiversity (Guo and others 2019;Potter 2018;Potter and Koch 2014;Potter andWoodall 2012, 2014); predictions and indicators of climate change effects on forests and forest tree species (Fei and others 2017, Heath and others 2015, Potter and Hargrove 2013; and the overall forest health indicator program (Woodall and others 2010). ...
Healthy ecosystems are those that are stable and sustainable, able to maintain their organization and autonomy over time while remaining resilient to stress (Costanza 1992). Healthy forests are vital to our future (Edmonds and others 2011), and consistent, large-scale, and long-term monitoring of key indicators of forest health status, change, and trends is necessary to identify forest resources deteriorating across large regions (Riitters and Tkacz 2004). The Forest Health Monitoring (FHM) program of the Forest Service, U.S. Department of Agriculture, with cooperating researchers within and outside the Forest Service and with State partners, quantifies status and trends in the health of U.S. forests. The analyses and results outlined in sections 1 and 2 of this FHM annual national report offer a snapshot of the current condition of U.S. forests from a national or multi-State regional perspective, incorporating baseline investigations of forest ecosystem health, examinations of change over time in forest health metrics, and assessments of developing threats to forest stability and sustainability. For datasets collected on an annual basis, analyses are presented from 2018 data. For datasets collected over several years, analyses are presented at a longer temporal scale. Finally, section 3 of this report presents summaries of results from recently completed Evaluation Monitoring (EM) projects that have been funded through the FHM national program to determine the extent, severity, and/or causes of specific forest health problems (FHM 2018).
... Attempts to highlight a species characteristic meant that some studies increased the weight of one of the parameters (e.g. Perrin and Waldren, 2020;Potter, 2018). For example, the weight of some rarity indexes were increased so as to also increase the importance of species with a small population size (Perrin and Waldren, 2020) or restricted geographical range (Potter, 2018;Roselaar et al., 2007). ...
... Perrin and Waldren, 2020;Potter, 2018). For example, the weight of some rarity indexes were increased so as to also increase the importance of species with a small population size (Perrin and Waldren, 2020) or restricted geographical range (Potter, 2018;Roselaar et al., 2007). In some case, three indexes of rarity were created separately for each of the three Rabinowitz parameters, and then weighted by only one of them (Godet et al., 2016). ...
Rarity has long been a question of great interest in a wide range of fields. A method to classify rare species should be simple and easy for different professional groups to learn. Rabinowitz is not only easy-to-follow but also one of the most accepted methods to classify rare species. This study proposes a rarity index (rr) based on Rabinowitz’s scheme. The index operates at the species level. Given a list of n species, the inverse of the geographical range in decimal degree (geographic range index – gri) of the maximum number of species habitats (habitat specificity index – hsi), and the maximum population size anywhere (population size index – psi) were calculated for each species. An average index rr = med(gri + hsi + psi) was calculated for each species from the gri, hsi, and psi indexes. The rr varies from 0 to 1: the closer rr is to 1, the rarer the species. A code in the R language to calculate each proposed measure is provided. The output of this code is a list of species with their respective indices. RR is useful in the ecology and biodiversity conservation fields. This index has the following advantages: (1) it uses three aspects of rarity to gain a synthetic index; (2) the three parameters have equal weights; and (3) it is easily followed by anyone who feels inclined to use it. Some directions on how it might be used are discussed.
... This allowed us to calculate plot-level indicators of potential impacts by insects and diseases, which were then summarized at scales relevant for conservation assessments. Additionally, we were able to detect geographic patterns of potential impacts [30] by forest insects and diseases in total, and within different agent groups, including those that are exotic and invasive. ...
... Among host families, Pinaceae encompassed the most species affected by any insect or disease agent (68), followed by Fagaceae (65), Cupressaceae (33), and Rosaceae (30) ( Table 1). For exotic agents, however, Fagaceae had the most affected hosts (65), with Pinaceae second (30), Sapindaceae third (19), and Salicaceae fourth (18). The same families had the most host/agent combinations, though in a different order, both for all agents (Pinaceae (307), Fagaceae (281), Rosaceae (111), and Cupressaceae (103)) and for exotic agents (Fagaceae (124), Salicaceae (41), Pinaceae (40), and Sapindaceae (35)). ...
Diseases and insects, particularly those that are non-native and invasive, arguably pose the most destructive threat to North American forests. Currently, both exotic and native insects and diseases are producing extensive ecological damage and economic impacts. As part of an effort to identify United States tree species and forests most vulnerable to these epidemics, we compiled a list of the most serious insect and disease threats for 419 native tree species and assigned a severity rating for each of the 1378 combinations between mature tree hosts and 339 distinct insect and disease agents. We then joined this list with data from a spatially unbiased and nationally consistent forest inventory to assess the potential ecological impacts of insect and disease infestations. Specifically, potential host species mortality for each host/agent combination was used to weight species importance values on approximately 132,000 Forest Inventory and Analysis (FIA) plots across the conterminous 48 United States. When summed on each plot, these weighted importance values represent an estimate of the proportion of the plot’s existing importance value at risk of being lost. These plot estimates were then used to identify statistically significant geographic hotspots and coldspots and of potential forest impacts associated with insects and diseases in total, and for different agent types. In general, the potential impacts of insects and diseases were greater in the West, where there are both fewer agents and less diverse forests. The impact of non-native invasive agents, however, was potentially greater in the East. Indeed, the impacts of current exotic pests could be greatly magnified across much of the Eastern United States if these agents are able to reach the entirety of their hosts’ ranges. Both the list of agent/host severities and the spatially explicit results can inform species-level vulnerability assessments and broad-scale forest sustainability reporting efforts, and should provide valuable information for decision-makers who need to determine which tree species and locations to target for monitoring efforts and pro-active management activities.
... By developing it, we revealed a parametric family of phylogenetic distinctiveness indices that could complement the most currently used "evolutionary distinctiveness" index (e.g. Isaac et al., 2007;Ibáñez-Álamo et al., 2017;Potter, 2018;Cooke et al., 2020) whose values are strongly dominated by the independent evolutionary history of a species (length of terminal branch in a phylogenetic tree with the species as tip; Redding et al., 2014). The parametric family indeed allows controlling the degree of influence of this independent evolutionary history on the distinctiveness index. ...
Rarity reflects the low abundance of a species while distinctiveness reflects its quality of being easy to recognize because it has unique functional characteristics and/or an isolated phylogenetic position. As such, the assemblage-level rarity of a species' functional and phylogenetic characteristics (that we name ‘effective originality’) results from both the rarity and the distinctiveness of this species. The functional and phylogenetic diversity of an assemblage then results from a compromise between the abundances and the effective originalities of the species it contains. Although the distinctiveness of a species itself depends on the abundance of the other species in the assemblage, distinctiveness indices that are available in the ecological literature scarcely consider abundance data. We develop a unifying framework that demonstrates the direct connections between measures of diversity, rarity, distinctiveness and effective originality. While developing our framework, we discovered a family of distinctiveness indices that permit a full control of the influence one wants to give to the strict uniqueness of a species (= its smallest functional or phylogenetic distance to another species in the assemblage). Illustrating our framework with bat phylogenetic diversity along a disturbance gradient in Mexico, we show how each component of rarity, distinctiveness and originality can be controlled to obtain efficient indicators for conservation. Overall our framework is aimed to improve conservation actions directed towards highly diverse areas and/or towards species whose loss would considerably decrease biodiversity by offering flexible quantitative tools where the influence of abundant versus rare, and ordinary versus original, species is understood and controlled.
... By developing it, we revealed a parametric family of phylogenetic distinctiveness indices that could complement the most currently used "evolutionary distinctiveness" index (e.g. Isaac et al., 2007;Ibáñez-álamo et al., 2017;Potter 2018;Cooke et al., 2020) whose values are strongly dominated by the independent evolutionary history of a species (length of terminal branch in a phylogenetic tree with the species as tip; Redding et al., 2014). The parametric family indeed allows controlling the . ...
Rarity reflects the low abundance of a species while distinctiveness reflects its quality of being easy to recognize because it has unique functional characteristics and/or an isolated phylogenetic position. As such, the assemblage-level rarity of a species' functional and phylogenetic characteristics (that we name 'effective originality') results from both the rarity and the distinctiveness of this species. The functional and phylogenetic diversity of an assemblage then results from a compromise between the abundances and the effective originalities of the species it contains. Although the distinctiveness of a species itself depends on the abundance of the other species in the assemblage, distinctiveness indices that are available in the ecological literature scarcely consider abundance data. We develop a unifying framework that demonstrates the direct connections between measures of diversity, rarity, distinctiveness and effective originality. While developing our framework, we discovered a family of distinctiveness indices that permit a full control of the influence one wants to give to the strict uniqueness of a species (=its smallest functional or phylogenetic distance to another species in the assemblage). Illustrating our framework with bat phylogenetic diversity along a disturbance gradient in Mexico, we show how each component of rarity, distinctiveness and originality can be controlled to obtain efficient indicators for conservation. Overall our framework is aimed to improve conservation actions directed towards highly diverse areas and/or towards species whose loss would considerably decrease biodiversity by offering flexible quantitative tools where the influence of abundant versus rare, and ordinary versus original, species is understood and controlled.
... To identify global amphibian conservation priority areas effectively, we propose an "integrative approach" that incorporates several factors related to the urgency of each species' conservation, including Data Deficient species, and quantifies the priority of increasing protected areas within a given region. We tested such an approach by assigning each amphibian species an integrative priority score based on the combination of its range size (Loyola et al., 2007), conservation status (IUCN, 2020), and taxonomic irreplaceability (Brooks et al., 2005;Potter, 2018). As several species do not have a definitive IUCN status (i.e., Data Deficient or Not Assessed), our approach uses a combination of biological and environmental factors to predict true status score. ...
Human activities are driving many species to the brink of extinction, and the current distribution of protected areas only weakly alleviates pressure on threatened species. This discrepancy reflects the presence of protected areas on lands available instead of the ecological, evolutionary, or conservation values of species present. Habitat loss consequently continued to impact threatened species, as illustrated by geographic patterns of biodiversity loss for amphibians. Given the need to better align the boundaries of protected areas with at-risk biodiversity, we assessed the importance of various factors for identifying global and biome-level conservation priority areas, specifically for amphibians. We identified, mapped, and ranked areas of critical conservation importance for all amphibian species on earth using a new integrative tool that scores the urgency of conserving each species and location based on a combination of species characteristics and ecoregion-level human impacts. Our integrative approach is novel in that it accounts for likely threats to Data Deficient species, considers the irreplaceability of unique species that are phylogenetically isolated, and addresses the localized conservation implications of species endemicity and projected future human impacts to an ecoregion. For comparison, we also mapped and ranked amphibian biodiversity using species richness and an EDGE score proxy. Our integrative approach predicted key regions for amphibian conservation that were not apparent when using a simple species richness or EDGE score proxy-based approach. Furthermore, by scaling conservation priority scores relative to biome, we identified several temperate and xeric regions of crucial yet overlooked conservation importance for amphibians. Until global amphibian diversity is thoroughly catalogued, we recommend using our integrative scoring approach to set geographic priorities for amphibian habitat protection, while acknowledging that this approach may be complemented by others (e.g., EDGE scores). Our study provides an avenue for avoiding common pitfalls of more simplistic species richness-based approaches for conservation planning, and can be used to improve the future design of protected areas.
... An accurate CMF species delimitation is fundamental to manage biodiversity and forest genetic resources (Scarascia-Mugnozza et al., 2000;Fady et al., 2016;Kavaliauskas et al., 2018;Potter, 2018). Due to a high degree of endemism, geographically scattered distribution and fragmentation by human activities, four CMF taxa are currently included in the IUCN red list as critically endangered or endangered (A. ...
Background and aims:
Inferring the evolutionary relationships of species and their boundaries is critical in order to understand patterns of diversification and their historical drivers. Despite Abies (Pinaceae) being the second most diverse group of conifers, the evolutionary history of Circum-Mediterranean firs (CMF) remains under debate.
Methods:
We used restriction site associated DNA sequencing (RAD-seq) on all proposed CMF taxa to investigate their phylogenetic relationships and taxonomic status.
Key results:
Based on thousands of genome-wide SNPs, we present here the first formal test of species delimitation, and the first fully resolved, complete species tree for CMF. We discovered that all previously recognized taxa in the Mediterranean should be treated as independent species, with the exception of A. tazaotana and A. marocana. An unexpectedly early pulse of speciation in the Oligocene-Miocene boundary is here documented for the group, pre-dating previous hypotheses by millions of years, revealing a complex evolutionary history encompassing both ancient and recent gene flow between distant lineages.
Conclusions:
Our phylogenomic results contribute to shed light on conifers' diversification. Our efforts to resolve the CMF phylogenetic relationships help refine their taxonomy and our knowledge of their evolution.
... Ecosystems that are unique to the study region have higher values (i.e., as A R approaches A N and a smaller portion of that ecosystem is found outside of the region) (Noss et al., 2002;Pressey et al., 1994). Endemism, which has been termed "regional responsibility", is included in prioritization because it allows allocation of conservation effort based the extent to which an ecosystem is associated with a particular region (Potter, 2018;Schmeller et al., 2008). By including both regional geographic rarity and endemism, our regional priority index accounts for the effect of setting conservation priorities at different geographic scales (Gauthier et al., 2010). ...
The ecotone between the Great Plains and the Eastern Deciduous Forest region is characterized by transitional grassland-forest ecosystems with a robust history of frequent fire regimes and fire-adapted natural communities. Historically, fires created a mosaic of prairies, savannas, woodlands, and forests juxtaposed by landscape controls. Humans have been strong determinants of fire regimes, causing frequent fires in historical times and an extended period of fire exclusion for nearly the last century. In recent decades, interest has increased in understanding the region’s fire ecology and management. This interest is driven by management objectives to promote and maintain plant and animal diversity, restore ecological processes, and increase ecosystem resilience. Plant species in the region exhibit adaptation to frequent fire regimes and wildlife species are associated with habitats maintained by fire. However, exclusion of fire over the past century has left a long-lasting mark on ecosystems by changing ecosystem structures and compositions and, in some cases, by eliminating fire-adapted natural communities. In the future, the rise of campaigns that promote appropriate fire uses will be contingent upon science, demonstrated management successes, public perspectives, and the broader challenges associated with global changes.
Ecological communities often exhibit greater resistance to biological invasions when these communities consist of species that are not closely related. The effective size of this resistance, however, varies geographically. Here we investigate the drivers of this heterogeneity in the context of known contributions of native trees to the resistance of forests in the eastern United States of America to plant invasions. Using 42,626 spatially referenced forest community observations, we quantified spatial heterogeneity in relationships between evolutionary relatedness amongst native trees and both invasive plant species richness and cover. We then modelled the variability amongst the 91 ecological sections of our study area in the slopes of these relationships in response to three factors known to affect invasion and evolutionary relationships –environmental harshness (as estimated via tree height), relative tree density and environmental variability. Invasive species richness and cover declined in plots having less evolutionarily related native trees. The degree to which they did, however, varied considerably amongst ecological sections. This variability was explained by an ecological section’s mean maximum tree height and, to a lesser degree, SD in maximum tree height ( R ²GLMM = 0.47 to 0.63). In general, less evolutionarily related native tree communities better resisted overall plant invasions in less harsh forests and in forests where the degree of harshness was more homogenous. These findings can guide future investigations aimed at identifying the mechanisms by which evolutionary relatedness of native species affects exotic species invasions and the environmental conditions under which these effects are most pronounced.
Significance
The strong focus on species extinctions, a critical aspect of the contemporary pulse of biological extinction, leads to a common misimpression that Earth’s biota is not immediately threatened, just slowly entering an episode of major biodiversity loss. This view overlooks the current trends of population declines and extinctions. Using a sample of 27,600 terrestrial vertebrate species, and a more detailed analysis of 177 mammal species, we show the extremely high degree of population decay in vertebrates, even in common “species of low concern.” Dwindling population sizes and range shrinkages amount to a massive anthropogenic erosion of biodiversity and of the ecosystem services essential to civilization. This “biological annihilation” underlines the seriousness for humanity of Earth’s ongoing sixth mass extinction event.
Genetic diversity provides the essential basis for the adaptation and resilience of tree species to environmental stress and change. The genetic conservation of tree species is an urgent global necessity as forest conversion and fragmentation continue apace, damaging insects and pathogens are transported between continents, and climate change alters local habitat suitability. Effective and efficient genetic conservation of tree species presents a substantial challenge because of the lack of basic information about many species, inadequate resources, and a historical lack of coordination within and between conservation sectors. Several cooperative efforts are already under way and are achieving conservation success, but much work remains. The Gene Conservation of Tree Species—Banking on the Future workshop in 2016 enabled the exchange of information and the creation of collaborations among tree conservation stakeholders. Several key themes emerged during the meeting’s presentations and dialogue, which are further explored in this paper. In situ conservation of species is the long-term goal and is often the most efficient approach for preserving the genetic diversity of many forest tree species. Whether existing reserves adequately protect species and are sufficient for future conservation needs is uncertain. Ex situ conservation is an important complement to in situ efforts, acting as an insurance measure against extinction, providing material for restoration, enabling additional research opportunities, and educating the public. Networks of botanic gardens, government agencies, and non-governmental organizations must continue to coordinate ex situ and in situ efforts to improve the efficiency and effectiveness of tree conservation efforts. Assessing and prioritizing which species and populations require genetic conservation and prioritizing among them is a critical need. Two key tree restoration needs are for wider dissemination of planting stock, particularly stock with resistance to insects and pathogens, and for specific silvicultural prescriptions that facilitate restoration efforts. Effective genetic conservation of forest trees will require ongoing cooperation among widely diverse groups of scientists, managers, and policymakers from the public and private sectors.
Climate change is one of several threats that will increase the likelihood that forest tree species could experience population-level extirpation or species-level extinction. Scientists and managers from throughout the United States Forest Service have cooperated to develop a framework for conservation priority-setting assessments of forest tree species. This framework uses trait data and predictions of expected climate change pressure to categorize and prioritize 339 native tree species for conservation, monitoring, management and restoration across all forested lands in the contiguous United States and Alaska. The framework allows for the quantitative grouping of species into vulnerability classes that may require different management and conservation strategies for maintaining the adaptive genetic variation of the species within each group. This categorization is based on risk factors relating to the species’ (1) exposure to climate change, (2) sensitivity to climate change, and (3) capacity to adapt to climate change. We used K-means clustering to group species into seven classes based on these three vulnerability dimensions. The most vulnerable class encompassed 35 species with high scores for all three vulnerability dimensions. These will require the most immediate conservation intervention. A group of 43 species had high exposure and sensitivity, probably requiring conservation assistance, while a group of 69 species had high exposure and low adaptive capacity, probably needing close monitoring. This assessment tool should be valuable for scientists and managers determining which species and populations to target for monitoring efforts and for pro-active gene conservation and management activities.
Ex situ conservation in germplasm and living collections is a major focus of global plant conservation strategies. Prioritizing species for ex situ collection is a necessary component of this effort for which sound strategies are needed. Phylogenetic considerations can play an important role in prioritization. Collections that are more phylogenetically diverse are likely to encompass more ecological and trait variation, and thus provide stronger conservation insurance and richer resources for future restoration efforts. However, phylogenetic criteria need to be weighed against other, potentially competing objectives. We used ex situ collection and threat rank data for North American angiosperms to investigate gaps in ex situ coverage and phylogenetic diversity of collections and to develop a flexible framework for prioritizing species across multiple objectives. We found that ex situ coverage of 18,766 North American angiosperm taxa was low with respect to the most vulnerable taxa: just 43% of vulnerable to critically imperiled taxa were in ex situ collections, far short of a year-2020 goal of 75%. In addition, species held in ex situ collections were phylogenetically clustered (P < 0.001), i.e., collections comprised less phylogenetic diversity than would be expected had species been drawn at random. These patterns support incorporating phylogenetic considerations into ex situ prioritization in a manner balanced with other criteria, such as vulnerability. To meet this need, we present the ‘PIECES’ index (Phylogenetically Informed Ex situ Conservation of Endangered Species). PIECES integrates phylogenetic considerations into a flexible framework for prioritizing species across competing objectives using multi-criteria decision analysis. Applying PIECES to prioritizing ex situ conservation of North American angiosperms, we show strong return on investment across multiple objectives, some of which are negatively correlated with each other. A spreadsheet-based decision support tool for North American angiosperms is provided; this tool can be customized to align with different conservation objectives.
Forests and trees throughout the world are increasingly affected by factors related to global change. Expanding international
trade has facilitated invasions of numerous insects and pathogens into new regions. Many of these invasions have caused substantial
forest damage, economic impacts and losses of ecosystem goods and services provided by trees. Climate change is already affecting
the geographic distribution of host trees and their associated insects and pathogens, with anticipated increases in pest impacts
by both native and invasive pests. Although climate change will benefit many forest insects, changes in thermal conditions
may disrupt evolved life history traits and cause phenological mismatches. Individually, the threats posed to forest ecosystems
by invasive pests and climate change are serious. Although interactions between these two drivers and their outcomes are poorly
understood and hence difficult to predict, it is clear that the cumulative impacts on forest ecosystems will be exacerbated.
Here we introduce and synthesize the information in this special issue of Forestry with articles that illustrate the impacts of invasions of insects and pathogens, climate change, forest management and their
interactions, as well as methods to predict, assess and mitigate these impacts. Most of these contributions were presented
at the XXIV IUFRO World Congress in 2014.
Context
Fine-scale ecological data collected across broad regions are becoming increasingly available. Appropriate geographic analyses of these data can help identify locations of ecological concern.
Objectives
We present one such approach, spatial association of scalable hexagons (SASH), which identifies locations where ecological phenomena occur at greater or lower frequencies than expected by chance. This approach is based on a sampling frame optimized for spatial neighborhood analysis, adjustable to the appropriate spatial resolution, and applicable to multiple data types.
Methods
We divided portions of the United States into scalable equal-area hexagonal cells and, using three types of data (field surveys, aerial surveys, satellite imagery), identified geographic clusters of forested areas having high and low values for (1) invasive plant diversity and cover, (2) mountain pine beetle-induced tree mortality, and (3) wildland forest fire occurrences.
Results
Using the SASH approach, we detected statistically significant patterns of plant invasion, bark beetle-induced tree mortality, and fire occurrence density that will be useful for understanding macroscale patterns and processes associated with each forest health threat, for assessing its ecological and economic impacts, and for identifying areas where specific management activities may be needed.
Conclusions
The presented method is a “big data” analysis tool with potential application for macrosystems ecology studies that require rigorous testing of hypotheses within a spatial framework. This method is a standard component of annual national reports on forest health status and trends across the United States and can be applied easily to other regions and datasets.
The Earth's evolutionary history is threatened by species loss in the current sixth mass extinction event in Earth's history. Such extinction events not only eliminate species but also their unique evolutionary histories. Here we review the expected loss of Earth's evolutionary history quantified by phylogenetic diversity (PD) and evolutionary distinctiveness (ED) at risk. Due to the general paucity of data, global evolutionary history losses have been predicted for only a few groups, such as mammals, birds, amphibians, plants, corals and fishes. Among these groups, there is now empirical support that extinction threats are clustered on the phylogeny; however this is not always a sufficient condition to cause higher loss of phylogenetic diversity in comparison to a scenario of random extinctions. Extinctions of the most evolutionarily distinct species and the shape of phylogenetic trees are additional factors that can elevate losses of evolutionary history. Consequently, impacts of species extinctions differ among groups and regions, and even if global losses are low within large groups, losses can be high among subgroups or within some regions. Further, we show that PD and ED are poorly protected by current conservation practices. While evolutionary history can be indirectly protected by current conservation schemes, optimizing its preservation requires integrating phylogenetic indices with those that capture rarity and extinction risk. Measures based on PD and ED could bring solutions to conservation issues, however they are still rarely used in practice, probably because the reasons to protect evolutionary history are not clear for practitioners or due to a lack of data. However, important advances have been made in the availability of phylogenetic trees and methods for their construction, as well as assessments of extinction risk. Some challenges remain, and looking forward, research should prioritize the assessment of expected PD and ED loss for more taxonomic groups and test the assumption that preserving ED and PD also protects rare species and ecosystem services. Such research will be useful to inform and guide the conservation of Earth's biodiversity and the services it provides.
Context
Published maps of global tree cover derived from Landsat data have indicated substantial changes in forest area from 2000 to 2012. The changes can be arranged in different patterns, with different consequences for forest fragmentation. Thus, the changes in forest area do not necessarily equate to changes in forest sustainability.
Objective
The objective is to assess global and regional changes in forest fragmentation in relation to the change of forest area from 2000 to 2012.
Methods
Using published global tree cover data, forest and forest interior areas were mapped in 2000 and 2012. The locations of forest interior change were compared to the locations of overall forest change to identify the direct (pixel level) and indirect (landscape level) components of forest interior change. The changes of forest interior area were compared to the changes of total forest area in each of 768 ecological regions.
Results
A 1.71 million km2 (3.2 %) net loss of global forest area translated to a net loss of 3.76 million km2 (9.9 %) of forest interior area. The difference in loss rates was consistent in most of the 768 ecological regions. The indirect component accounted for 2.44 million km2 of the net forest interior change, compared to 1.32 million km2 that was attributable to the direct component.
Conclusion
Forest area loss alone from 2000 to 2012 underestimates ecological risks from forest fragmentation. In addition to the direct loss of forest, there was a widespread shift of the remaining global forest to a more fragmented condition.
Humans depend on biodiversity in myriad ways, yet species are being rapidly lost due to human activities. The ecosystem services approach to conservation tries to establish the value that society derives from the natural world such that the true cost of proposed development actions becomes apparent to decision makers. Species are an integral component of ecosystems, and the value they provide in terms of services should be a standard part of ecosystem assessments. However, assessing the value of species is difficult and will always remain incomplete. Some of the most difficult species' benefits to assess are those that accrue unexpectedly or are wholly unanticipated. In this review, we consider recent examples from a wide variety of species and a diverse set of ecosystem services that illustrate this point and support the application of the precautionary principle to decisions affecting the natural world.
Copyright © 2015 Elsevier Ltd. All rights reserved.
Significance
The United States has one of the oldest and most sophisticated systems of protected areas in the world. Given the large amount of information on the country’s biodiversity, and the potential resources available, one might expect it to do well in protecting biodiversity. We find that it does not. The United States protected areas do not adequately cover the country’s unique species. To improve the coverage, we map priorities for multiple taxa and recommend specific areas for immediate conservation attention. These areas contain a mix of public and private land, meaning that major progress in conservation will require actions in both the public and private sectors, and will succeed only if done in the correct areas.
We assess relict species as potentially biased samples of taxonomic groups because all of their close relatives went extinct.•Relicts are diverse, either old or young species that show or do not show ancestral states in terms of characters or spatial distribution.•Therefore, they should not be used a priori to assert phenotypic/genotypic conservatism or biota permanence.•Relicts inform us about extinction/diversification processes and can be ranked of very high value for conservation biology, being the only surviving representatives of large groups that are mainly extinct.
a b s t r a c t Understanding the genetic impacts of forest management practices is crucial for conservation and management of forest genetic resources. Forest management practices based on selective and clear cut systems followed by natural or artificial regeneration can impact population structure and mating patterns, thus gene flow and genetic diversity. Survival and productivity of both tree and non-tree species can be compromised or, possibly, enhanced. The extent of genetic impacts depend on the management system applied, stand structure as well as species' distribution, demography, biological attributes and ecology. The impact of management practices is reviewed and synthesized for temperate, boreal and tropical forests based on experimental and simulation studies. In addition, the effects of genetically improved planting materials and establishment of large scale plantations on natural forests are examined. Recommendations are made for genetically sustainable forest management practices. Ó 2014 Elsevier B.V. All rights reserved.
Because the conservation of biodiversity occurs under time and resource constraints, it is necessary to prioritize species most deserving of attention. Natural history collections have been identified as a valuable source of information in applied conservation practice, particularly for species-rich taxa like plants. Here, online herbarium information was combined with a novel, straightforward priority setting approach to screen a large list of rare vascular plant species (n = 418) in Saskatchewan, Canada. Data was quantified to develop priority scores (for a given species) using three key criteria: (1) provincial responsibility in species survival, (2) species local population characteristics, and (3) the anthropogenic threats causing species to be rare. The use of a hierarchy of the three criteria, wherein provincial responsibility was assigned the most weight, resulted in the highest ranking for 13 species that exist only in Saskatchewan and no other Canadian province or territory. The list is a first step in identifying species deserving of conservation attention and/or further study, while the method itself was deemed to be highly relevant to conservation managers and decision makers due to its scale adaptability and fairly minimal resource requirements.
Background
A principal function of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) is to “perform regular and timely assessments of knowledge on biodiversity.” In December 2013, its second plenary session approved a program to begin a global assessment in 2015. The Convention on Biological Diversity (CBD) and five other biodiversity-related conventions have adopted IPBES as their science-policy interface, so these assessments will be important in evaluating progress toward the CBD’s Aichi Targets of the Strategic Plan for Biodiversity 2011–2020. As a contribution toward such assessment, we review the biodiversity of eukaryote species and their extinction rates, distributions, and protection. We document what we know, how it likely differs from what we do not, and how these differences affect biodiversity statistics. Interestingly, several targets explicitly mention “known species”—a strong, if implicit, statement of incomplete knowledge. We start by asking how many species are known and how many remain undescribed. We then consider by how much human actions inflate extinction rates. Much depends on where species are, because different biomes contain different numbers of species of different susceptibilities. Biomes also suffer different levels of damage and have unequal levels of protection. How extinction rates will change depends on how and where threats expand and whether greater protection counters them.
Advances
Recent studies have clarified where the most vulnerable species live, where and how humanity changes the planet, and how this drives extinctions. These data are increasingly accessible, bringing greater transparency to science and governance. Taxonomic catalogs of plants, terrestrial vertebrates, freshwater fish, and some marine taxa are sufficient to assess their status and the limitations of our knowledge. Most species are undescribed, however. The species we know best have large geographical ranges and are often common within them. Most known species have small ranges, however, and such species are typically newer discoveries. The numbers of known species with very small ranges are increasing quickly, even in well-known taxa. They are geographically concentrated and are disproportionately likely to be threatened or already extinct. We expect unknown species to share these characteristics. Current rates of extinction are about 1000 times the background rate of extinction. These are higher than previously estimated and likely still underestimated. Future rates will depend on many factors and are poised to increase. Finally, although there has been rapid progress in developing protected areas, such efforts are not ecologically representative, nor do they optimally protect biodiversity.
Outlook
Progress on assessing biodiversity will emerge from continued expansion of the many recently created online databases, combining them with new global data sources on changing land and ocean use and with increasingly crowdsourced data on species’ distributions. Examples of practical conservation that follow from using combined data in Colombia and Brazil can be found at www.savingspecies.org and www.youtube.com/watch?v=R3zjeJW2NVk .
Integrated, efficient, and global prioritization approaches are necessary to manage the ongoing loss of species and their associated function. "Evolutionary distinctness" measures a species' contribution to the total evolutionary history of its clade and is expected to capture uniquely divergent genomes and functions. Here we demonstrate how such a metric identifies species and regions of particular value for safeguarding evolutionary diversity.
Among the world's 9,993 recognized bird species, evolutionary distinctness is very heterogeneously distributed on the phylogenetic tree and varies little with range size or threat level. Species representing the most evolutionary history over the smallest area (those with greatest "evolutionary distinctness rarity") as well as some of the most imperiled distinct species are often concentrated outside the species-rich regions and countries, suggesting they may not be well captured by current conservation planning. We perform global cross-species and spatial analyses and generate minimum conservation sets to assess the benefits of the presented species-level metrics. We find that prioritizing imperiled species by their evolutionary distinctness and geographic rarity is a surprisingly effective and spatially economical way to maintain the total evolutionary information encompassing the world's birds. We identify potential conservation gaps in relation to the existing reserve network that in particular highlight islands as effective priority areas.
The presented distinctness metrics are effective yet easily communicable and versatile tools to assist objective global conservation decision making. Given that most species will remain ecologically understudied, combining growing phylogenetic and spatial data may be an efficient way to retain vital aspects of biodiversity.
increase at a faster rate in the future, accompanied by changes in precipitation patterns and increases in the
occurrence of extreme weather events. In western North America, projected increases in mean annual temperatures range from �1 to 3.5° C by the 2050s, and although projected changes in precipitation patterns
are more complex to model, more frequent and severe droughts are expected in many areas. For long-lived
tree species, because of their relatively slow rates of migration, climate change will likely result in a ismatch
between the climate that trees are currently adapted to and the climate that trees will experience in the future.
Individual trees or populations exposed to climate conditions outside their climatic niches may be aladapted,
resulting in compromised productivity and increased vulnerability to disturbance, specifically insects and
pathogens. In western North America, as elsewhere, several recent assessments have concluded that forests are being affected by climate change and will become increasingly vulnerable to mortality as a result of the direct and indirect effects of climate change. Droughts associated with higher temperatures may accelerate levels of tree mortality, for example, because elevated temperatures increase metabolic rates without increasing photosynthesis rates, thus compromising a tree’s ability to create defenses against insects and pathogens. Distributions of the climatic niches of some tree species in western North America are predicted to change by up to 200% during this century based on bioclimate envelope modeling. We discuss the science of climate change, the implications of projected climatic changes to forest ecosystems in western North America, and the essential roles of forest managers, policymakers, and scientists in addressing climate change.
A comprehensive environmental monitoring program based on a sound statistical design is necessary to provide estimates of the status of, and changes or trends in, the condition of ecological resources. A sampling design based upon a systematic grid can adequately assess the condition of many types of resources and retain flexibility for addressing new issues as they arise. The randomization of this grid requires that it be regular and retain equal-area cells when projected on the surface of the earth. After review of existing approaches to constructing regular subdivisions of the earth's surface, we propose the development of the sampling grid on the Lambert azimuthal equal-area map projection of the earth's surface to the face of a truncated icosahedron fit to the globe. This geometric model has less deviation in area when subdivided as a spherical tessellation than any of the spherical Platonic solids, and less distortion in shape over the extent of a face when used for a projection surface by the Lambert azimuthal projection. A hexagon face of the truncated icosahedron covers the entire conterminous United States, and can be decomposed into a triangular grid at an appropriate density for sampling. The geometry of the triangular grid provides for varying the density, and points on the grid can be addressed in several ways.
Around the world, the human-induced collapses of populations and species have triggered a sixth mass extinction crisis, with rare species often being the first to disappear. Although the role of species diversity in the maintenance of ecosystem processes has been widely investigated, the role of rare species remains controversial. A critical issue is whether common species insure against the loss of functions supported by rare species. This issue is even more critical in species-rich ecosystems where high functional redundancy among species is likely and where it is thus often assumed that ecosystem functioning is buffered against species loss. Here, using extensive datasets of species occurrences and functional traits from three highly diverse ecosystems (846 coral reef fishes, 2,979 alpine plants, and 662 tropical trees), we demonstrate that the most distinct combinations of traits are supported predominantly by rare species both in terms of local abundance and regional occupancy. Moreover, species that have low functional redundancy and are likely to support the most vulnerable functions, with no other species carrying similar combinations of traits, are rarer than expected by chance in all three ecosystems. For instance, 63% and 98% of fish species that are likely to support highly vulnerable functions in coral reef ecosystems are locally and regionally rare, respectively. For alpine plants, 32% and 89% of such species are locally and regionally rare, respectively. Remarkably, 47% of fish species and 55% of tropical tree species that are likely to support highly vulnerable functions have only one individual per sample on average. Our results emphasize the importance of rare species conservation, even in highly diverse ecosystems, which are thought to exhibit high functional redundancy. Rare species offer more than aesthetic, cultural, or taxonomic diversity value; they disproportionately increase the potential breadth of functions provided by ecosystems across spatial scales. As such, they are likely to insure against future uncertainty arising from climate change and the ever-increasing anthropogenic pressures on ecosystems. Our results call for a more detailed understanding of the role of rarity and functional vulnerability in ecosystem functioning.
Protected areas are a cornerstone of local, regional, and global strategies for the conservation of biodiversity. However, the ecological performance of these areas, both in terms of the representation and the maintenance of key biodiversity features, remains poorly understood. A large and rapidly expanding literature bears on these issues, but it is highly fragmented, principally comprises particular case studies, and employs a diverse array of approaches. Here we provide a synthetic review of this work, discriminating between issues of performance of inventory and condition at the scale of individual protected areas, portfolios, and networks of protected areas. We emphasize the insights that follow and the links between the different issues, as well as highlight the major problems that remain unresolved.
Small populations are predicted to have reduced capacity to adapt to environmental change for two reasons. First, population genetic models indicate that genetic variation and potential response to selection should be positively correlated with population size. The empirical support for this prediction is mixed: DNA markers usually reveal low heterozygosity in small populations, whereas quantitative traits show reduced heritability only in the smallest and most inbred populations. Quantitative variation can even increase in bottlenecked populations although this effect seems unlikely to increase the adaptive potential of populations. Second, individuals in small populations have lower fitness owing to environmental stress and genetic problems such as inbreeding, which can substantially increase the extinction probability of populations in changing environments. This second reason has not been included in assessments of critical population size assuring evolvability and makes it likely that many sm...
Aim Assessing whether environmental and human factors influenced the spatial distribution and the dynamics of regionally rare plant species since the late nineteenth century, and whether these spatial and temporal patterns of rare species occurrences differ according to their chorology (level of endemism and biogeographic affinity).
Location An area extending over 6250 km ² in the French Mediterranean Region.
Methods We used two botanical surveys achieved in 1886 and in 2001, and considered species rare if occurring in only one or two sites in the study area. Each rare species was assigned to a group of endemism level (restricted endemic, non‐endemic), and of biogeographic affinity (Mediterranean, South/Central European, Mountain, Eurosiberian). A 1 × 1 km grid was applied to the study zone. Generalized linear models were developed to study the spatial distribution and the fate of rare species occurrences (local extinction vs. local persistence between 1886 and 2001), as a function of environmental and human variables. Multivariate analyses were used to test whether the spatial distribution and the fate of rare species occurrences differed according to their chorology.
Results In 2001, rare species as a whole tended to occur at higher altitude, in zones dominated by semi‐natural open habitats, and where cultivated area had decreased in the last 30 years. Between 1886 and 2001, rare species were the most prone to local extinction in zones where human population density, cultivated area and livestock density had increased the most. Between 1886 and 2001, rare species had a higher probability of local persistence in zones of high altitude and steep slope, on basic bedrocks and with low cultivated area. Rare species with Mountain and Eurosiberian affinities occurred in marginal habitats in the study region, i.e. on gneiss‐micaschist bedrocks and at high altitudes, whereas Mediterranean and South/Central European rare species occupied more varied environmental conditions. Between 1886 and 2001, Eurosiberian rare species showed high rates of local extinction whereas Mediterranean rare species had a significantly higher probability of local persistence. Restricted endemic species mostly occurred in zones of high slope, low human population density, and where cultivated area had decreased in the last 30 years. Occurrences of restricted endemics remained significantly stable between 1886 and 2001.
Main conclusions Environmental and land‐use changes that occurred over the twentieth century in the Mediterranean Basin had significant impacts on the spatial distribution and on the long‐term dynamics of rare species occurrences. Urbanization and recent agriculture intensification, occurring mainly in coastal plains and littoral zones, caused most local extinctions of rare species from 1886 to 2001. Local populations of Eurosiberian species, which reach their range limits in marginal zones of the Mediterranean, also appear to be highly vulnerable. Conversely, most restricted endemic species occur in habitats with harsh topography and low human disturbance and have a higher potential of local persistence.
Introduced in this paper is a family of statistics, G, that can be used as a measure of spatial association in a number of circumstances. The basic statistic is derived, its properties are identified, and its advantages explained. Several of the G statistics make it possible to evaluate the spatial association of a variable within a specified distance of a single point. A comparison is made between a general G statistic and Moran’s I for similar hypothetical and empirical conditions. The empirical work includes studies of sudden infant death syndrome by county in North Carolina and dwelling unit prices in metropolitan San Diego by zip-code districts. Results indicate that G statistics should be used in conjunction with I in order to identify characteristics of patterns not revealed by the I statistic alone and, specifically, the G
i
and G
i
∗ statistics enable us to detect local “pockets” of dependence that may not show up when using global statistics.
In this paper, we introduce the concept of ‘originality of a species within a set’ in order to indicate the average rarity of all the features belonging to this species. Using a phylogenetic tree of 70 species of New World terrestrial Carnivora, we suggest measuring the originality by a probability distribution. This maximizes the expected number of features shared by two species randomly drawn from the set. By using this new index, we take account of branch lengths whereas current indices of originality focus on tree topology. As a supplement to Nee and May's optimizing algorithm, we find that originality must be one of the criteria used in conservation planning.
Climate is a potent selective force in natural populations, yet the importance of adaptation in the response of plant species to past climate change has been questioned. As many species are unlikely to migrate fast enough to track the rapidly changing climate of the future, adaptation must play an increasingly important role in their response. In this paper we review recent work that has documented climate-related genetic diversity within populations or on the microgeographical scale. We then describe studies that have looked at the potential evolutionary responses of plant populations to future climate change. We argue that in fragmented landscapes, rapid climate change has the potential to overwhelm the capacity for adaptation in many plant populations and dramatically alter their genetic composition. The consequences are likely to include unpredictable changes in the presence and abundance of species within communities and a reduction in their ability to resist and recover from further environmental perturbations, such as pest and disease outbreaks and extreme climatic events. Overall, a range-wide increase in extinction risk is likely to result. We call for further research into understanding the causes and consequences of the maintenance and loss of climate-related genetic diversity within populations.
Increased use of forest resources and a shrinking forestland base threaten the sustainability of forest genetic resources
and highlight the importance of conservation and sustainable management of these resources. As forest trees are normally the
keystone species of forest ecosystems, their continued existence is essential for many floral and faunal associations of these
ecosystems. Major concepts, challenges and opportunities for conservation of forest genetic resources are briefly discussed
in this paper. The major challenges include population decline and population structure changes due to forest removal and
conversion of forest land to other uses,forest fragmentation, forestry practices, climate change, disease conditions,introduced
pests, atmospheric pollution, and introgressive hybridization. Developing scientifically sound conservation strategies, maintaining
minimum viable population sizes, and deployment of genetically engineered organisms represent other important challenges in
conservation. The usefulness of various biochemical and molecular genetic markers, adaptive traits, and genetic diversity
measures for developing conservation strategies for in situ and ex situ genetic resource conservation are also discussed. Major opportunities for conservation of forest genetic resources include:
use of molecular genetic markers and adaptive traits for developing conservation strategies; in situ conservation through natural reserves,protected areas, and sustainable forest management practices; ex situ conservation through germplasm banks, common garden archives, seed banks, DNA banks, and tissue culture and cryopreservation;
incorporation of disease, pest, and stress tolerance traits through genetic transformation;plantation forestry; and ecological
restoration of rare or declining tree species and populations. Forest genetic resource conservation and resource use should
be considered complementary rather than contradictory to each other.
The aim of this multiauthor book is to introduce readers with a wide variety of backgrounds to the principles and practice of forest conservation genetics through 22 chapters which deal with: genetic principles and basic genetic processes; genetic threats to forest species and in situ conservation; the effects of domestication and ex situ restoration on forest gene pools; and the interations between genetics and socio-economics as they relate to formation of forest policy. Where possible, case studies have been emphasized to provide practical illustrations of concepts being discussed. To this end, the population genetics package, POPGENE, is included with the book as a CD-ROM to provide a hands-on tool for the analysis and interpretation of a wide range of genetic data. The references are all given at the end of the book. There is a subject index. The individual chapters are noticed separately on CAB Abstracts.
Introduced in this paper is a family of statistics, G, that can be used as a measure of spatial association in a number of circumstances. The basic statistic is derived, its properties are identified, and its advantages explained. Several of the G statistics make it possible to evaluate the spatial association of a variable within a specified distance of a single point. A comparison is made between a general G statistic andMoran’s I for similar hypothetical and empirical conditions. The empiricalwork includes studies of sudden infant death syndrome by county in North Carolina and dwelling unit prices in metropolitan San Diego by zip-code districts. Results indicate that G statistics should be used in conjunction with I in order to identify characteristics of patterns not revealed by the I statistic alone and, specifically, the Gi and G∗ i statistics enable us to detect local “pockets” of dependence that may not show up when using global statistics.
This document is based on previous documentation of the nationally standardized Forest Inventory and Analysis database (Hansen and others 1992; Woudenberg and Farrenkopf 1995; Miles and others 2001). Documentation of the structure of the Forest Inventory and Analysis database (FIADB) for Phase 2 data, as well as codes and definitions, is provided. Examples for producing population level estimates are also presented. This database provides a consistent framework for storing forest inventory data across all ownerships for the entire United States. These data are available to the public.
1. Here, I present a new, multifunctional phylogenetics package, phytools, for the R statistical computing environment.
2. The focus of the package is on methods for phylogenetic comparative biology; however, it also includes tools for tree inference, phylogeny input/output, plotting, manipulation and several other tasks.
3. I describe and tabulate the major methods implemented in phytools, and in addition provide some demonstration of its use in the form of two illustrative examples.
4. Finally, I conclude by briefly describing an active web-log that I use to document present and future developments for phytools. I also note other web resources for phylogenetics in the R computational environment.
Evaluating the effectiveness of protected areas for sustaining biodiversity is crucial to achieving conservation outcomes. While studies of effectiveness have improved our understanding of protected-area design and management, few investigations (< 5%) have quantified the ecological performance of reserves for conserving species. Here, we present an empirical evaluation of protected-area effectiveness using long-term measures of a vulnerable assemblage of species. We compare forest and woodland bird diversity in the Australian Capital Territory over 11 yr on protected and unprotected areas located in temperate eucalypt woodland and matched by key habitat attributes. We examine separately the response of birds to protected areas established prior to 1995 and after 1995 when fundamental changes were made to regional conservation policy. Bird diversity was measured in richness, occurrence of vulnerable species, individual species trajectories and functional trait groups. We found that protected areas were effective in maintaining woody vegetation cover in the study region, but were less effective in the protection of the target bird species assemblage. Protected areas were less species rich than unprotected areas, with significant declines in richness across sites protected prior to 1995. Small, specialised and vulnerable species showed stronger associations with unprotected areas than protected areas. Our findings indicate that recently established reserves (post-1995) are performing similarly to unprotected woodland areas in terms of maintaining woodland bird diversity, and that both of these areas are more effective in the conservation of woodland bird populations than reserves established prior to 1995. We demonstrate that the conservation value of protected areas is strongly influenced by the physical characteristics, as well as the landscape context, of a given reserve and can diminish with changes in surrounding land use over time. Both protected areas and off-reserve conservation schemes have important roles to play in securing species populations.
In developing red data books of threatened species, the World Conservation Union uses measures of rarity, rates of decline, and population fragmentation to categorize species according to their risk of extinction. However, most quantitative measures of these three concepts are sensitive to the scale at which they are made. In particular, definitions of rarity based on an area-of-occupancy threshold can nearly always be met if area of occupancy is calculated from a sufficiently fine-scale (high-resolution) grid. Recommendations for dealing with scale dependency include (1) choosing a standard scale of measurement, (2) using multiple scales of measurement, and (3) developing indices that combine information from multiple scales. As an example of the second and third approach, the construction of a species' scale-area curve represents a unifying method for quantifying all three indicators of extinction risk—rarity, rate of decline, and population fragmentation—as functions of area of occupancy and measurement scale. A multiscale analysis is also of practical importance because measurements made at different scales are relevant to different extinction processes. Coarse-scale measures of rarity are most appropriate when threat is assessed on the basis of spatially autocorrelated events of a large extent, such as global climate change, whereas fine-scale measures may best predict extinction risk due to local processes such as demographic stochasticity. We illustrate our arguments with a case study of the British distributions of two related plant species that show a 200-fold reversal in their relative rarity when measured at different scales.
1. The urgency and scale of the global biodiversity crisis requires the application of generalized predictors of a species’ likelihood of going extinct or becoming invasive in non-native areas. A common approach is to correlate species’ ecological and life-history characteristics (attributes, traits) with the probability of becoming either threatened (responding negatively to human activity), or invasive (responding positively). The limitation of previous studies is that the fates of becoming threatened or invasive have generally been treated in isolation.
2. Here we consider the problem of threat and invasiveness in unison based on analysis of one of the largest-ever species attributes data bases (8906 species) compiled for a single plant family (Fabaceae). We used generalized linear mixed-effects models (using taxonomic grouping to control for within-family phylogenetic relationships) to correlate species’ life-history and ecological traits to three response variables: probability of being (i) threatened or not, (ii) invasive or not, and (iii) threatened or invasive.
3. We found that tall, annual, range-restricted species with tree-like growth forms, inhabiting closed-forest and lowland sites are more likely to be threatened. Conversely, climbing and herbaceous species that naturally span multiple floristic kingdoms and habitat types are more likely
to become invasive.
4. Synthesis. These results support the idea that at least for one of the richest plant families, species’ life-history and ecological traits correlate with a fate response to anthropogenic global change. Our results show that species do demonstrate particular susceptibility to either fate based on their evolved traits, and that traits generally correlated with invasiveness are also those that correlate with a reduced probability of becoming threatened.
The Baja California Peninsula is home to 85 species of cacti, of which 54 are endemic, highlighting its importance as a cactus diverse region within Mexico. Many species are under threat due to collection pressure and habitat loss, but ensuring maximal protection of cacti species requires a better understanding of diversity patterns. We assessed species richness, endemism, and phylogenetic and morphological diversity using herbarium records and a molecular phylogeny for 82 species of cacti found in the peninsula. The four diversity measures were estimated for the existing nature reserve network and for 314 hexagrids of 726km2. Using the hexagrid data, we surveyed our results for areas that best complement the current protected cacti diversity in the Baja California Peninsula. Currently, the natural reserve network in Baja shelters an important amount of the cacti diversity (74% of the species, 85.9% of the phylogenetic diversity, 76% of endemics and all the growth forms). While species richness produced several solutions to complement the diversity protected, by identifying priority species (endemic species with high contribution to overall PD) one best solution is reported. Three areas (San Matías, Magdalena and Margarita Islands and El Triunfo), selected using species richness, PD and endemism, best complement the diversity currently protected, increasing species richness to 89%, PD to 94% and endemism to 89%, and should be considered in future conservation plans. Two of these areas could be included within nature reserves already established.
The objective of this research is to examine the extent to which phylogenetic and geographical drivers of rarity may interact to help us better predict distributions of rare taxa. This information is useful to conservation biologists when considering plans for the effective capture of biological diversity within reserve systems. We use 33 floras, distributed globally among five biomes, to assess pattern of rarity across taxonomic group size for plants. We show that small plant families (1–10 taxa) contain consistently fewer rare taxa than expected, while rare plants are proportionately over-represented in large plant families (>100 taxa). We also examine the distribution of species within families. The degree to which species are inequitably distributed among families varied systematically across floristic biomes. Mediterranean floras, in particular, are characterized by a greater than expected fraction of their species pool concentrated within large families, suggesting a high propensity for rarity simply by virtue of having a higher proportion of their constituent taxa within groups with a high likelihood of rarity. Finally, an analysis of a suite of floras using a common system of identifying rarity shows that the fraction of species within floras that are rare is predicted both by flora size and by a general metric (the Gini coefficient) of inequality among family sizes. Together, these patterns suggest a high degree of predictability in the distribution of rarity in plants that may reflect underlying natural speciation and extinction processes.
The realization of conservation goals requires strategies for managing
whole landscapes including areas allocated to both production and protection.
Reserves alone are not adequate for nature conservation but they are the cornerstone
on which regional strategies are built. Reserves have two main roles. They
should sample or represent the biodiversity of each region and they should
separate this biodiversity from processes that threaten its persistence. Existing
reserve systems throughout the world contain a biased sample of biodiversity,
usually that of remote places and other areas that are unsuitable for commercial
activities. A more systematic approach to locating and designing reserves
has been evolving and this approach will need to be implemented if a large
proportion of today's biodiversity is to exist in a future of increasing numbers
of people and their demands on natural resources.
The history of humankind is one of modification of the forested environment (Glacken, 1967; Ledig, 1992), through processes which Ledig (1992) has categorized as deforestation, exploitation, fragmentation, demographic and habitat alterations, environmental deterioration, translocation and domestication. Some (e.g. Perlin, 1989; Harrison, 1992) have postulated that these modifications represent a defining characteristic of civilizations; in any case, it is apparent that the political economies of resource use define the contexts and prospects for in situ conservation of forest genetic resources, just as they do for forests and trees more generally (e.g. Ledig, 1986; Byron and Waugh, 1988; Westoby, 1989; Romm, 1991; Colchester and Lohmann, 1993).
A diverse array of fire-adapted plant communities once covered the eastern United States. European settlement greatly altered fire regimes, often increasing fire occurrence (e.g., in northern hardwoods) or substantially decreasing it (e.g., in tallgrass prairies). Notwithstanding these changes, fire suppression policies, beginning around the 1920s, greatly reduced fire throughout the East, with profound ecological consequences. Fire-maintained open lands converted to closed-canopy forests. As a result of shading, shade-tolerant, fire-sensitive plants began to replace heliophytic (sun-loving), fire-tolerant plants. A positive feedback cycle—which we term “mesophication”—ensued, whereby microenvironmental conditions (cool, damp, and shaded conditions; less flammable fuel beds) continually improve for shade-tolerant mesophytic species and deteriorate for shade-intolerant, fire-adapted species. Plant communities are undergoing rapid compositional and structural changes, some with no ecological antecedent. Stand-level species richness is declining, and will decline further, as numerous fire-adapted plants are replaced by a limited set of shade-tolerant, fire-sensitive species. As this process continues, the effort and cost required to restore fire-adapted ecosystems escalate rapidly.
Aim In an era of global habitat loss and species extinction, conservation biology is increasingly becoming a science of triage. A key approach has been the designation of global biodiversity hotspots – areas of high species richness and endemism – prioritizing regions that are disproportionately valuable. However, traditional hotspot approaches leave absent information on species evolutionary histories. We argue that prioritizing the preservation of evolutionary diversity is one way to maximize genotypic and functional diversity, providing ecosystems with the greatest number of options for dealing with an uncertain future.
Location Global.
Methods We review methods for encapsulating phylogenetic diversity and distinctiveness and provide an illustration of how phylogenetic metrics can be extended to include data on geographical rarity and inform conservation prioritization at biogeographic scales.
Results Abundance‐weighted metrics of evolutionary diversity can be used to simultaneously prioritize populations, species, habitats and biogeographical regions.
Main conclusion Policy makers need to know where scarce conservation funds should be focused to maximize gains and minimize the loss of biological diversity. By incorporating these evolutionary diversity metrics into prioritization schemes, managers can better quantify the valuation of different regions based on evolutionary information.
Knowledge of the spatial distribution of weed infestations over regional scales is essential for effective management of source populations and to assess future threats. To this end, the distributions of Nassella trichotoma across a study area in south-east New South Wales, Australia, were analysed using the geographically local Getis–Ord Gi* spatial hotspot clustering statistic. The clustering of N. trichotoma observations was analysed at three infestation levels: presence (at any density), patch level and the occasional plant level. The results indicate that there are c. 578 km2 of cells containing N. trichotoma in strongly clustered infestations, 11.2 km2 within weakly clustered infestations distinct from the main clusters, and 55 km2 that are not clustered. There are 117 km2 of strongly clustered patch level cells, 3 km2 in distinct but weak clusters, and none outside of a cluster area. Of the occasional plant level cells, 329 km2 are strongly clustered, 6.2 km2 are in distinct but weak clusters, and 19 km2 are not clustered. These results provide a mechanism by which control efforts can be prioritized. The analysis approach described in this paper provides a consistent, quantitative and repeatable approach to assess weed infestations across regional scales and can be applied to any weed species for which spatial distribution data are available.
Aim To determine whether life‐history characters that affect population persistence (e.g. habit and life span) and those that influence reproductive success (e.g. sexual system and fruit type) are non‐randomly correlated with extinction risk (i.e. threat category) in the Australian flora ( c . 19,000 species, of which c . 14% is threatened). To identify patterns that present useful conservation directions. To understand patterns of extinction risk in the Australian flora at a broad scale.
Location Continental Australia.
Methods A country‐wide exploration of four life‐history characters in the Australian flora ( n = 18,822 species) was undertaken using reference texts, expert opinion, herbarium records and field work. For each character and threat‐category combination, a G ‐test (using a log‐linear model) was performed to test the null hypothesis that the two factors were independent in their effects on count. A generalized linear model (GLM) with a logit link and binomial error distribution was constructed with the proportion of taxa in each extinction risk category as the response variable and the habit, sex and fruit‐type characters as explanatory terms. In a separate approach, we investigated patterns across the threat categories of non‐endangered extant, endangered, and extinct using a multinomial model. We examined whether or not species‐poor genera were more likely to contain threatened or extinct species than species‐rich genera. A GLM with a binomial error distribution and logit link function was constructed to obtain a weighted regression on the proportion of species listed as extinct or endangered within a genus versus the log of the size of the genus. We also used a supertree analysis and character tracing to investigate the role of phylogeny on extinction risk.
Results We found that the Australian flora is primarily composed of bisexual shrubs with dry‐dehiscent fruits. Dioecious breeding systems (separate female and male flowers on separate plants) in many floras are the predominant unisexual system, but in Australia there are unexpectedly high levels of monoecy (separate female and male flowers on the same plant). Within the extinct data set of 31 species we detected a significant departure from that expected for habit but not for life span, sexual system or fruit type. There are significantly fewer trees on the extinct list than expected. This may reflect the greater resilience of trees than of other growth habits to extinction processes as well as the observation time‐frame. Within the endangered data set of 450 species we found significant differences in the representation of the observed characters from that expected within sex systems and fruit types. We show that, depending on the life form, unisexual breeding systems can be significantly and positively associated with endangered species compared with non‐threatened species. For example, there are more monoecious species than expected by chance among the tree species listed as endangered but fewer among the herbaceous life forms. Threat category was found to be non‐randomly clustered in some clades.
Main conclusions Life‐history characters in certain combinations are predictive of extinction risk. Phylogeny is also an important component of extinction risk. We suggest that specific life‐history characters could be used for conservation planning and as an early warning sign for detecting vulnerability in lists of species.
Setting species priorities is commonly based on the assessment of multiple conservation criteria, and point-scoring methods
are broadly used for obtaining ranked species lists. However, the implications of different procedures in the performance
and application of resulting lists have been scarcely investigated. In this study, we test the effect of using distinct transformation
and summarization of criteria for computing ranked lists for species prioritization and allocation of seed collection resources.
The study is focused on the Cantabrian Range (Spain), where 127 vascular plants of conservation concern were scored according
to four criteria (threat, protection, endemicity and rarity) related to different geographical scales. Four conservation priority
indices (CPI) were computed using a combination of (a) ordinal- versus quantile-weighted transformation and (b) mean versus
factorial summarization. Quantile transformation and factorial summarization provided a more quantitative CPI. Although the
contribution of criteria to the final indices was different under quantile and ordinal transformations, the four CPI were
strongly correlated. However, slight differences between indices reflected divergences in the selection of species priorities
when low conservation funds are available, and 14 to 32% of the species composition in priority groups changed. Our results
suggest that different point-scoring procedures might have high impact on the application of priority lists for selecting
conservation targets, especially when different funding scenarios are compared. We also recommend to (1) avoid ordinal scoring
methods, (2) use unequally weighted transformations and (3) apply point-scoring methods based on multi-scale criteria for
integrating existing lists in biogeographical areas
KeywordsBiogeography-Cantabrian Range-Conservation priority-Ex situ-Plant conservation-Point-scoring-Ranking criteria-Resources allocation-Species priorities