240 research outputs found

    The Role of Gardens in Integrated Conservation Practice

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    Gardens and horticulturists play an increasingly important role in plant conservation, both in situ and ex situ. Integrated research and conservation of species intends to work across fields to connect science to conservation practice by engaging actors from different sectors, including gardens. The case of integrated conservation of Quercus brandegeei, a microendemic oak species in Baja California Sur, Mexico, is presented as an example of a collaboration between gardens and academic researchers to create a species-specific conservation plan that incorporates horticultural knowledge

    Remote Sensing of Plant Biodiversity

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    At last, here it is. For some time now, the world has needed a text providing both a new theoretical foundation and practical guidance on how to approach the challenge of biodiversity decline in the Anthropocene. This is a global challenge demanding global approaches to understand its scope and implications. Until recently, we have simply lacked the tools to do so. We are now entering an era in which we can realistically begin to understand and monitor the multidimensional phenomenon of biodiversity at a planetary scale. This era builds upon three centuries of scientific research on biodiversity at site to landscape levels, augmented over the past two decades by airborne research platforms carrying spectrometers, lidars, and radars for larger-scale observations. Emerging international networks of fine-grain in-situ biodiversity observations complemented by space-based sensors offering coarser-grain imagery—but global coverage—of ecosystem composition, function, and structure together provide the information necessary to monitor and track change in biodiversity globally. This book is a road map on how to observe and interpret terrestrial biodiversity across scales through plants—primary producers and the foundation of the trophic pyramid. It honors the fact that biodiversity exists across different dimensions, including both phylogenetic and functional. Then, it relates these aspects of biodiversity to another dimension, the spectral diversity captured by remote sensing instruments operating at scales from leaf to canopy to biome. The biodiversity community has needed a Rosetta Stone to translate between the language of satellite remote sensing and its resulting spectral diversity and the languages of those exploring the phylogenetic diversity and functional trait diversity of life on Earth. By assembling the vital translation, this volume has globalized our ability to track biodiversity state and change. Thus, a global problem meets a key component of the global solution. The editors have cleverly built the book in three parts. Part 1 addresses the theory behind the remote sensing of terrestrial plant biodiversity: why spectral diversity relates to plant functional traits and phylogenetic diversity. Starting with first principles, it connects plant biochemistry, physiology, and macroecology to remotely sensed spectra and explores the processes behind the patterns we observe. Examples from the field demonstrate the rising synthesis of multiple disciplines to create a new cross-spatial and spectral science of biodiversity. Part 2 discusses how to implement this evolving science. It focuses on the plethora of novel in-situ, airborne, and spaceborne Earth observation tools currently and soon to be available while also incorporating the ways of actually making biodiversity measurements with these tools. It includes instructions for organizing and conducting a field campaign. Throughout, there is a focus on the burgeoning field of imaging spectroscopy, which is revolutionizing our ability to characterize life remotely. Part 3 takes on an overarching issue for any effort to globalize biodiversity observations, the issue of scale. It addresses scale from two perspectives. The first is that of combining observations across varying spatial, temporal, and spectral resolutions for better understanding—that is, what scales and how. This is an area of ongoing research driven by a confluence of innovations in observation systems and rising computational capacity. The second is the organizational side of the scaling challenge. It explores existing frameworks for integrating multi-scale observations within global networks. The focus here is on what practical steps can be taken to organize multi-scale data and what is already happening in this regard. These frameworks include essential biodiversity variables and the Group on Earth Observations Biodiversity Observation Network (GEO BON). This book constitutes an end-to-end guide uniting the latest in research and techniques to cover the theory and practice of the remote sensing of plant biodiversity. In putting it together, the editors and their coauthors, all preeminent in their fields, have done a great service for those seeking to understand and conserve life on Earth—just when we need it most. For if the world is ever to construct a coordinated response to the planetwide crisis of biodiversity loss, it must first assemble adequate—and global—measures of what we are losing

    Habitat specialization and the role of trait lability in structuring diverse willow (genus Salix) communities

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    Abstract. The co-occurrence of closely related species is challenging to explain because biotic filters are expected to limit the ecological similarity of species within communities. To investigate the mechanisms important in facilitating species' co-occurrence in diverse willow and poplar communities, we examined functional diversity and community phylogenetic structure along a hydrologic gradient. We focused on traits related to drought tolerance, leaf hydraulics, and recruitment, and examined species' phylogenetic relatedness and trait lability using a molecular phylogeny. Within habitats, species exhibited phenotypic clustering, and across the landscape, species distributions were correlated with their functional traits in a manner consistent with environmental filtering. With increasing water availability, communities changed from being phylogenetically even to being phylogenetically clustered. We suggest that this shift results from environmental filtering acting on conserved traits in wet habitats and labile traits in dry habitats. Taken together, these results suggest that environmental filtering is important to community assembly along the entire hydrologic gradient within this system. Although many of the traits important to habitat specialization in upland habitats are phylogenetically labile, species' habitat affinity is phylogenetically conserved overall, indicating that niche conservatism can occur as an emergent property despite trait lability. This study demonstrates the complementary nature of trait and community phylogenetic analyses and how these methods can be used to better understand the processes involved in community assembly along environmental gradients

    Shocks to the system: Community assembly of the oak savanna in a 40-year fire frequency experiment

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    Fire is a major force driving the evolution of plants and the structure and function of ecosystems globally. It thus likely operates as an important environmental filter that selects for species that have evolved to tolerate and depend on fire. Across a 40-year experimental fire gradient from frequently burned open savanna to unburned dense woodland in Minnesota, USA, we examined the relationships among community assembly, evolutionary history, and functional trait composition. Close relatives had similar abundance patterns across the fire gradient, providing evidence for phylogenetic conservatism in fire adaptation and highlighting the importance of shared ancestry in predicting species responses to fire. Phylogenetic beta diversity was greatest between the most extreme fire treatments across the gradient, indicating that species in the most contrasting fire regimes were most distantly related. Fire strongly influenced diversity, co-occurrence patterns, and leaf trait means and variances within communities. The most frequently burned communities had the highest species richness, exhibited the most resource-conservative leaf traits, and spanned the greatest number of phylogenetic lineages but harbored more close relatives within those lineages than other communities. In contrast, unburned communities had the lowest species diversity, the most acquisitive leaf traits, and the fewest phylogenetic lineages, but close relatives co-occurred less frequently. The largest difference in abundance between treatments occurred within the Rosales, Asteraceae, Vitaceae, and the Poaceae; woody Rosales were strongly selected for in unburned communities, while composites and grasses of the Poaceae were strongly selected for under frequent burning. A major climatic perturbation of consecutive hot, dry summers in the late 1980s prompted a significant shift in the functional and phylogenetic composition of communities. Greater than expected turnover in species composition occurred following the drought years, and then again during the subsequent five-year rebound period. Just after the drought year, turnover was greatest among recently diverged taxa, whereas during the rebound period turnover was greater among taxa that diverged deep in the phylogeny. The drought years also caused a short-term shift in functional traits, including declines in specific leaf area and leaf nitrogen content and an increase in leaf length. These results indicate that the phylogenetic and functional trait composition of communities are responsive both to fire gradients and to shocks to the system, such as climatic perturbation

    Habitat specialization and the role of trait lability in structuring diverse willow (genus Salix) communities

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    Abstract. The co-occurrence of closely related species is challenging to explain because biotic filters are expected to limit the ecological similarity of species within communities. To investigate the mechanisms important in facilitating species' co-occurrence in diverse willow and poplar communities, we examined functional diversity and community phylogenetic structure along a hydrologic gradient. We focused on traits related to drought tolerance, leaf hydraulics, and recruitment, and examined species' phylogenetic relatedness and trait lability using a molecular phylogeny. Within habitats, species exhibited phenotypic clustering, and across the landscape, species distributions were correlated with their functional traits in a manner consistent with environmental filtering. With increasing water availability, communities changed from being phylogenetically even to being phylogenetically clustered. We suggest that this shift results from environmental filtering acting on conserved traits in wet habitats and labile traits in dry habitats. Taken together, these results suggest that environmental filtering is important to community assembly along the entire hydrologic gradient within this system. Although many of the traits important to habitat specialization in upland habitats are phylogenetically labile, species' habitat affinity is phylogenetically conserved overall, indicating that niche conservatism can occur as an emergent property despite trait lability. This study demonstrates the complementary nature of trait and community phylogenetic analyses and how these methods can be used to better understand the processes involved in community assembly along environmental gradients

    Patterns of Beta Diversity of Vascular Plants and Their Correspondence With Biome Boundaries Across North America

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    Understanding why species composition and diversity varies spatially and with environmental variation is a long-standing theme in macroecological research. Numerous hypotheses have been generated to explain species and phylogenetic diversity gradients. Much less attention has been invested in explaining patterns of beta diversity. Biomes boundaries are thought to represent major shifts in abiotic variables accompanied by vegetation patterns and composition as a consequence of long-term interactions between the environment and the diversification and sorting of species. Using North American plant distribution data, phylogenetic information and three functional traits (SLA, seed mass, and plant height), we explicitly tested whether beta diversity is associated with biome boundaries and the extent to which two components of beta diversity—turnover and nestedness—for three dimensions of biodiversity (taxonomic, phylogenetic, and functional)—are associated with contrasting environments and linked to different patterns of historical climatic stability. We found that dimensions of vascular plant beta diversity are strongly coupled and vary considerably across North America, with turnover more influential in biomes with higher species richness and greater environmental stability and nestedness more influential in species-poor biomes characterized by high environmental variability. These results can be interpreted to indicate that in harsher climates with less stability explain beta diversity, while in warmer, wetter more stable climates, patterns of endemism associated with speciation processes, as well as local environmental sorting processes, contribute to beta diversity. Similar to prior studies, we conclude that patterns of similarity among communities and biomes reflects biogeographic legacies of how vascular plant diversity arose and was shaped by historical and ecological processes

    The spatial sensitivity of the spectral diversity–biodiversity relationship: an experimental test in a prairie grassland

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    Remote sensing has been used to detect plant biodiversity in a range of ecosystems based on the varying spectral properties of different species or functional groups. However, the most appropriate spatial resolution necessary to detect diversity remains unclear. At coarse resolution, differences among spectral patterns may be too weak to detect. In contrast, at fine resolution, redundant information may be introduced. To explore the effect of spatial resolution, we studied the scale dependence of spectral diversity in a prairie ecosystem experiment at Cedar Creek Ecosystem Science Reserve, Minnesota, USA. Our study involved a scaling exercise comparing synthetic pixels resampled from high-resolution images within manipulated diversity treatments. Hyperspectral data were collected using several instruments on both ground and airborne platforms. We used the coefficient of variation (CV) of spectral reflectance in space as the indicator of spectral diversity and then compared CV at different scales ranging from 1 mm2 to 1 m2 to conventional biodiversity metrics, including species richness, Shannon’s index, Simpson’s index, phylogenetic species variation, and phylogenetic species evenness. In this study, higher species richness plots generally had higher CV. CV showed higher correlations with Shannon’s index and Simpson’s index than did species richness alone, indicating evenness contributed to the spectral diversity. Correlations with species richness and Simpson’s index were generally higher than with phylogenetic species variation and evenness measured at comparable spatial scales, indicating weaker relationships between spectral diversity and phylogenetic diversity metrics than with species diversity metrics. High resolution imaging spectrometer data (1 mm2 pixels) showed the highest sensitivity to diversity level. With decreasing spatial resolution, the difference in CV between diversity levels decreased and greatly reduced the optical detectability of biodiversity. The optimal pixel size for distinguishing a diversity in these prairie plots appeared to be around 1 mm to 10 cm, a spatial scale similar to the size of an individual herbaceous plant. These results indicate a strong scaledependence of the spectral diversity-biodiversity relationships, with spectral diversity best able to detect a combination of species richness and evenness, and more weakly detecting phylogenetic diversity. These findings can be used to guide airborne studies of biodiversity and develop more effective large-scale biodiversity sampling methods

    Analisis Kesediaan Membayar Wtp (Willingness To Pay) dalam Upaya Pengelolaan Obyek Wisata Taman Alun Kapuas Pontianak, Kalimantan Barat

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    Berbagai fungsi yang terkait dengan sumber daya alam (fungsi ekologis, sosial, ekonomi, dan arsitektural) dannilai estetika yang dimilikinya (obyek dan lingkungan) dapat meningkatkan kualitas lingkungan dan untukkelangsungan kehidupan perkotaan juga dapat menjadi nilai kebanggaan dan identitas kota. Sebagai obyekwisata alam, Taman Alunalun Kapuas belum tertata dengan baik, pelaksanaan upaya pengelolaan objek wisataTaman Alun Kapuas membutuhkan biaya yang tidak sedikit. Untuk itu diharapkan bagi pengunjung untukmembayar dalam pengelolaan Taman Alun Kapuas. Penelitian ini menggunakan analisis regresi logistik dalammenganalisis faktor-faktor kesediaan pengunjung untuk membayar. Sedangkan metode CVM (ContingenValuation Method) digunakan untuk mengestimasi biaya yang akan dikeluarkan oleh pengunjung, dan metoderegresi berganda digunakan untuk menganalisis faktor-faktor apa yang mempengaruhi besar kesediaanmembayar pengunjung. Program yang dapat membantu dalam penelitian ini yaitu Microsoft Excel 2007 danMinitab For Windows Realise 16. Hasil penelitian menunjukkan bahwa sebanyak 84% responden bersediamembayar dalam upaya pengelolaan lingkungan obyek wisata Taman Alun Kapuas. Faktor-faktor yangmempengaruhi kesediaan membayar responden pengunjung dalam upaya pengelolaan lingkungan obyekwisata Taman Alun Kapuas antara lain pendapatan (PNDPTN3) dan pengetahuan (PNGTHUAN). Nilai rata-rataWTP responden pengunjung adalah sebesar Rp 3360,00/orang. Faktor yang mempengaruhi nilai WTPresponden yaitu usia (U)

    Canopy spectral reflectance detects oak wilt at the landscape scale using phylogenetic discrimination

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    The oak wilt disease caused by the invasive fungal pathogen Bretziella fagacearum is one of the greatest threats to oak-dominated forests across the Eastern United States. Accurate detection and monitoring over large areas are necessary for management activities to effectively mitigate and prevent the spread of oak wilt. Canopy spectral reflectance contains both phylogenetic and physiological information across the visible near-infrared (VNIR) and short-wave infrared (SWIR) ranges that can be used to identify diseased red oaks. We develop partial least square discriminant analysis (PLS-DA) models using airborne hyperspectral reflectance to detect diseased canopies and assess the importance of VNIR, SWIR, phylogeny, and physiology for oak wilt detection. We achieve high accuracy through a three-step phylogenetic process in which we first distinguish oaks from other species (90% accuracy), then red oaks from white oaks (Quercus macrocarpa) (93% accuracy), and, lastly, infected from non-infected trees (80% accuracy). Including SWIR wavelengths increased model accuracy by ca. 20% relative to models based on VIS-NIR wavelengths alone; using a phylogenetic approach also increased model accuracy by ca. 20% over a single-step classification. SWIR wavelengths include spectral information important in differentiating red oaks from other species and in distinguishing diseased red oaks from healthy red oaks. We determined the most important wavelengths to identify oak species, red oaks, and diseased red oaks. We also demonstrated that several multispectral indices associated with physiological decline can detect differences between healthy and diseased trees. The wavelengths in these indices also tended to be among the most important wavelengths for disease detection within PLS-DA models, indicating a convergence of the methods. Indices were most significant for detecting oak wilt during late August, especially those associated with canopy photosynthetic activity and water status. Our study suggests that coupling phylogenetics, physiology, and canopy spectral reflectance provides an interdisciplinary and comprehensive approach that enables detection of forest diseases at large scales. These results have potential for direct application by forest managers for detection to initiate actions to mitigate the disease and prevent pathogen spread

    Seasonal Variation in the NDVI–Species Richness Relationship in a Prairie Grassland Experiment (Cedar Creek)

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    Species richness generally promotes ecosystem productivity, although the shape of the relationship varies and remains the subject of debate. One reason for this uncertainty lies in the multitude of methodological approaches to sampling biodiversity and productivity, some of which can be subjective. Remote sensing offers new, objective ways of assessing productivity and biodiversity. In this study, we tested the species richness–productivity relationship using a common remote sensing index, the Normalized Difference Vegetation Index (NDVI), as a measure of productivity in experimental prairie grassland plots (Cedar Creek). Our study spanned a growing season (May to October, 2014) to evaluate dynamic changes in the NDVI–species richness relationship through time and in relation to environmental variables and phenology. We show that NDVI, which is strongly associated with vegetation percent cover and biomass, is related to biodiversity for this prairie site, but it is also strongly influenced by other factors, including canopy growth stage, short-term water stress and shifting flowering patterns. Remarkably, the NDVI-biodiversity correlation peaked at mid-season, a period of warm, dry conditions and anthesis, when NDVI reached a local minimum. These findings confirm a positive, but dynamic, productivity–diversity relationship and highlight the benefit of optical remote sensing as an objective and non-invasive tool for assessing diversity–productivity relationships
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