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INFLUENCE OF LANDSCAPE complexity AND LAND MANAGEMENT ON WOODY PLANT DIVERSITY IN NORTHERN SPAIN

JOURNAL OF VEGETATION SCIENCE 1994年第4期5卷 505-516页

作者： RESCIA, AJ SCHMITZ, MF DEAGAR, PM DEPABLO, CL ATAURI, JA PINEDA, FD Departamento Interuniversitario de Ecología Facultad de Biología Universidad Complutense E-28040 Madrid Spain

Changes in land use, particularly the type of forest management, and their spatial pattern, especially woody plant diversity, were related to each other in an area in the Basque region (Spain). The number and diversity of boundaries between landscape patches is related to the development of the spatial complexity of the landscape, C(s), measured in bits and defined as: C(s) = H(b) . H(1), where H(b) is the boundary diversity and H(1) the spatial heterogeneity generated by these boundaries. As to the vegetation types, changes in land use over the last 50 yr have resulted in a less diversified and more fragmented landscape, especially on a small scale. Forest plantation has become the predominant land use. The frequency of land use changes is studied regarding its influence on the present levels of woody plant diversity.

关键词： BOUNDARY DYNAMICS CONSERVATION FOREST MANAGEMENT FRAGMENTATION NATIVE FOREST PATTERN PINUS PLANTATION spatial complexity URDAIBAI BIOSPHERE RESERVE

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Measurement of plant architecture in seven aquatic plants

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JOURNAL OF FRESHWATER ECOLOGY 1996年第3期11卷 311-318页

作者： Dibble, ED Killgore, KJ Dick, GO USA ENGINEERS WATERWAYS EXPT STNVICKSBURGMS 39180 USA ENGINEERS AQUAT ECOSYST RES FACILLEWISVILLETX 75056

We quantified architectural characteristics of seven aquatic macrophytes by measuring spatial complexity and shading properties. The plants were: Egeria densa, Hydrilla verticillata, Myriophyllum spicatum Potamogeton nodosus, Potamogeton pectinatus, Vallisineria americana, and Zosterella dubia). Two replicates of each plant were cultured in aquaria in concrete raceways. Light transparency and vertical and horizontal interstices measurements were taken at three strata level in each plant species. spatial complexity was calculated by adding the ratio between interstices frequency and size from both vertical and horizontal axes. Mean density and size of plant interstices differed significantly among plant species (x(2) = 123, df = 6, P < 0.01) and were greatest along horizontal axes. Plant complexity was lowest in M. spicatum and highest in P. pectinatus. Shading properties were significantly different among plants (x(2) = 40, df = 5, P < 0.01), and significant inter- and intra-plant strata differences were noted.

关键词： Mathematical analysis Plant architecture Plant, aquatic spatial complexity

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The novel use of harvest policies and rapid visual assessment to manage spatially complex abalone resources (Genus Haliotis)

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FISHERIES RESEARCH 2008年第3期94卷 330-338页

作者： Prince, Jeremy D. Peeters, Harry Gorfine, Harry Day, Robert W. Biospher PL S Fremantle WA 6162 Australia Western Zone Abalone Div Assoc Geelong N Vic 3215 Australia Univ Melbourne Dept Zool Parkville Vic 3010 Australia

To date, the development of fisheries harvest policies has typically focused on the use of indices estimated from quantitative stock assessment models. Where does this leave the small-scale and spatially complex resources for which costs and logistics prevent adequate data collection for the construction of quantitative assessment models at scales appropriate for the component populations being fished? This paper presents a novel harvest policy framework developed in Australia by the Victorian Western Zone Abalone Diver's Association (WADA) to assess and manage their resource at the scale of component abalone reefs (100s-1000s m). This novel harvest policy framework uses a rapid visual evaluation of population fecundity based on shell shape and appearance. Codified and applied using a decision tree, it is being used in Australia by an increasing number of zonal abalone industry associations. Abalone populations on reef complexes are being assessed and managed with voluntary catch caps and voluntary minimum lengths larger than legal minimum lengths. It will probably be decades before a satisfactory quantitative analysis on the efficacy of the approach will be possible, but positive anecdotal accounts and the relatively rapid spread of the approach suggest industry members believe they are seeing benefits. (c) 2008 Elsevier B.V. All rights reserved.

关键词： Harvest policy Decision tree Rapid visual assessment spatial complexity Haliotids

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Rapid soil formation after glacial retreat shaped by spatial patterns of organic matter accrual in microaggregates

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GLOBAL CHANGE BIOLOGY 2018年第4期24卷 1637-1650页

作者： Schweizer, Steffen A. Hoeschen, Carmen Schlueter, Steffen Koegel-Knabner, Ingrid Mueller, Carsten W. Tech Univ Munich Chair Soil Sci TUM Sch Life Sci Weihenstephan Freising Weihenstephan Germany UFZ Helmholtz Ctr Environm Res Dept Soil Syst Sci Halle Saale Germany Tech Univ Munich Inst Adv Study Garching Germany

Global change contributes to the retreat of glaciers at unprecedented rates. The deglaciation facilitates biogeochemical processes on glacial deposits with initiating soil formation as an important driver of evolving ecosystems. The underlying mechanisms of soil formation and the association of soil organic matter (SOM) with mineral particles remain unclear, although further insights are critical to understand carbon sequestration in soils. We investigated the microspatial arrangement of SOM coatings at intact soil microaggregate structures during various stages of ecosystem development from 15 to >700years after deglaciation in the proglacial environment of the Damma glacier (Switzerland). The functionally important clay-sized fraction (<2m) was separated into two density fractions with different amounts of organo-mineral associations: light (1.6-2.2g/cm(3)) and heavy (>2.2g/cm(3)). To quantify how SOM extends across the surface of mineral particles (coverage) and whether SOM coatings are distributed in fragmented or connected patterns (connectivity), we developed an image analysis protocol based on nanoscale secondary ion mass spectrometry (NanoSIMS). We classified SOM and mineral areas depending on the O-16(-), C-12(-), and (CN-)-C-12-N-14 distributions. With increasing time after glacial retreat, the microspatial coverage and connectivity of SOM increased rapidly. The rapid soil formation led to a succession of patchy distributed to more connected SOM coatings on soil microaggregates. The maximum coverage of 55% at >700years suggests direct evidence for SOM sequestration being decoupled from the mineral surface, as it was not completely masked by SOM and retained its functionality as an ion exchange site. The chemical composition of SOM coatings showed a rapid change toward a higher CN:C ratio already at 75years after glacial retreat, which was associated with microbial succession patterns reflecting high N assimilation. Our results demonstrate that rapid SOM se

关键词： biogeochemical soil interfaces glacier forefield mineral-associated organic matter nanoscale secondary ion mass spectrometry organic coating organo-mineral associations soil carbon sequestration spatial complexity

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Changes in the structural complexity of the aged brain

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AGING CELL 2007年第3期6卷 275-284页

作者： Dickstein, Dara L. Kabaso, Doron Rocher, Anne B. Luebke, Jennifer I. Wearne, Susan L. Hof, Patrick R. Mt Sinai Sch Med Dept Neurosci New York NY 10029 USA Mt Sinai Sch Med Lab Biomath New York NY 10029 USA Mt Sinai Sch Med Computat Neurobiol & Imaging Ctr New York NY 10029 USA Boston Univ Sch Med Dept Anat & Neurobiol Boston MA 02215 USA

Structural changes of neurons in the brain during aging are complex and not well understood. Neurons have significant homeostatic control of essential brain functions, including synaptic excitability, gene expression, and metabolic regulation. Any deviations from the norm can have severe consequences as seen in aging and injury. In this review, we present some of the structural adaptations that neurons undergo throughout normal and pathological aging and discuss their effects on electrophysiological properties and cognition. During aging, it is evident that neurons undergo morphological changes such as a reduction in the complexity of dendrite arborization and dendritic length. Spine numbers are also decreased, and because spines are the major sites for excitatory synapses, changes in their numbers could reflect a change in synaptic densities. This idea has been supported by studies that demonstrate a decrease in the overall frequency of spontaneous glutamate receptor-mediated excitatory responses, as well as a decrease in the levels of alpha-amino3-hydroxy-5-methylisoxazole-4-propionic acid and N-methyl-D-aspartate receptor expression. Other properties such as gamma-taminobutyric acid A receptor-mediated inhibitory responses and action potential firing rates are both significantly increased with age. These findings suggest that age-related neuronal dysfunction, which must underlie observed decline in cognitive function, probably involves a host of other subtle changes within the cortex that could include alterations in receptors, loss of dendrites, and spines and myelin dystrophy, as well as the alterations in synaptic transmission. Together these multiple alterations in the brain may constitute the substrate for age-related loss of cognitive function.

关键词： aging Alzheimer's disease neuroscience spatial complexity electrophysiology dendrites spines

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Vegetation response to Holocene climate change in East Asian monsoon-margin region

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EARTH-SCIENCE REVIEWS 2012年第1-2期113卷 1-10页

作者： Zhao, Yan Yu, Zicheng Lanzhou Univ Res Sch Arid Environm & Climate Change MOE Key Lab Western Chinas Environm Syst Lanzhou 730000 Peoples R China Lehigh Univ Dept Earth & Environm Sci Bethlehem PA 18015 USA

Fossil pollen records from 20 sites with reliable chronologies and high-resolution data in the East Asian monsoon margin region were synthesized to document Holocene vegetation and climate change and to understand the large-scale controls. The vegetation experienced different changes over the Holocene in various sub-regions. (1) Near the boundary between modern forest and temperate steppe in Northeast China, forest showed clear expansion in the middle Holocene. (2) In central China near the boundary between steppe/forest and desert, vegetation showed various patterns at different sites. (3) Further west on the Tibetan Plateau near the boundary between highland meadow/steppe and semi-desert/desert, forest expanded at most sites during the early and middle Holocene. Our synthesis indicates that climate in the margin region was slightly moist in the early Holocene, wettest in the middle Holocene, and dry in the late Holocene, though there are regional differences as reflected by vegetation change. This general pattern is very different from either monsoon- or westerly-dominated regions. The maximum moisture occurred during the early Holocene in the monsoon region, while the arid central Asia dominated by the westerlies was driest in the early Holocene and wettest in the mid-Holocene. The interplay of the Asian summer monsoon, westerlies, topography and regional vegetation factors might have contributed to this spatial complexity. (C) 2012 Elsevier B.V. All rights reserved.

关键词： East Asian monsoon Fossil pollen Holocene Climate change Vegetation response spatial complexity

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A fragmented landscape in northern Spain analyzed at different spatial scales: Implications for management

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JOURNAL OF VEGETATION SCIENCE 1997年第3期8卷 343-352页

作者： Rescia, AJ Schmitz, MF deAgar, PM dePablo, CL Pineda, FD Departamento Interuniversitario de Ecología Facultad de Biología Universidad Complutense E-28040 Madrid Spain [*] Author for correspondence Tel. +34 1 3945086 Fax +34 1 3945081 E-mail ma296@eucmvx.sim.ucm.es

Changes in landscape pattern are analyzed through sampling plots of different size taken along a time series of aerial photographs at three scales of observation. The results indicate that variation in the landscape pattern shows a less pronounced change at the local scale than at larger scales and that appreciation of the structure of this landscape and description of its temporal variation are scale-dependent. Analysis of the spatial complexity on different scales, measured by the C(s) index (Rescia et al. 1994), shows that the number of types of boundary between patches is the most important landscape component on all scales. spatial complexity and the number of boundary types are related to woody plant diversity at a local scale. In the studied landscape, human activities on a local scale strongly influence the spatial configuration on a regional scale. This concerns territorial planning, the main problem of which is not found in selecting a correct observation scale, but in recognizing that the change under study occurs at various scales at the same time. This underlines the importance of analysing the landscape pattern at different scales with the design of plans and conservation programs in mind.

关键词： boundary heterogeneity landscape scale spatial complexity woody plant diversity

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The association of magnetoencephalography high-frequency oscillations with epilepsy types and a ripple-based method with source-level connectivity for mapping epilepsy sources

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CNS NEUROSCIENCE & THERAPEUTICS 2023年第5期29卷 1423-1433页

作者： Shi, Li-juan Li, Can-Cheng Lin, Yi-cong Ding, Cheng-tao Wang, Yu-ping Zhang, Ji-cong Beihang Univ Sch Biol Sci & Med Engn Beijing 100191 Peoples R China Beihang Univ Beijing Adv Innovat Ctr Big Data Based Precis Med Beijing Peoples R China Beihang Univ Beijing Adv Innovat Ctr Biomed Engn Beijing Peoples R China Capital Med Univ Xuanwu Hosp Dept Neurol Beijing 100053 Peoples R China Brain Funct Dis & Neuromodulat Beijing Key Lab Beijing Peoples R China Beihang Univ Hefei Innovat Res Inst Hefei Anhui Peoples R China

ObjectiveTo explore the association between high-frequency oscillations (HFOs) and epilepsy types and to improve the accuracy of source localization. MethodsMagnetoencephalography (MEG) ripples of 63 drug-resistant epilepsy patients were detected. Ripple rates, distribution, spatial complexity, and the clustering coefficient of ripple channels were used for the preliminary classification of lateral temporal lobe epilepsy (LTLE), mesial temporal lobe epilepsy (MTLE), and nontemporal lobe epilepsy (NTLE), mainly frontal lobe epilepsy (FLE). Furthermore, the seizure site identification was improved using the Tucker LCMV method and source-level betweenness centrality. ResultsRipple rates were significantly higher in MTLE than in LTLE and NTLE (p < 0.05). The LTLE and MTLE were mainly distributed in the temporal lobe, followed by the parietal lobe, occipital lobe, and frontal lobe, whereas MTLE ripples were mainly distributed in the frontal lobe, then parietal lobe and occipital lobe. Nevertheless, the NTLE ripples were primarily in the frontal lobe and partially in the occipital lobe (p < 0.05). Meanwhile, the spatial complexity of NTLE was significantly higher than that of LTLE and MTLE and was lowest in MTLE (p < 0.01). However, an opposite trend was observed for the standardized clustering coefficient compared with spatial complexity (p < 0.01). Finally, the tucker algorithm showed a higher percentage of ripples at the surgical site when the betweenness centrality was added (p < 0.01). ConclusionThis study demonstrated that HFO rates, distribution, spatial complexity, and clustering coefficient of ripple channels varied considerably among the three epilepsy types. Additionally, tucker MEG estimation combined with ripple rates based on the source-level functional connectivity is a promising approach for presurgical epilepsy evaluation.

关键词： functional connectivity MEG ripple source location spatial complexity tucker decomposition

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Inter-patch connectivity and intra-patch structure differentially alter prey consumption by multiple predators

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ECOSPHERE 2016年第11期7卷 1-14页

作者： Pitcher, Kristopher A. Soluk, Daniel A. Univ South Dakota Dept Biol 414 E Clark St Vermillion SD 57069 USA

Structural habitat complexity (SHC) and functional habitat connectivity (FHC) have important effects on predator-prey interactions and exert a strong influence on community structure/dynamics in terrestrial and aquatic ecosystems. Although these factors vary simultaneously in most systems, their interactive effects are poorly understood. Using artificial pond mesocosms and multiple prey types, we manipulated plant density (SHC: low, high) and inter-patch distance (FHC: short, long) in a full factorial design to test for potential interactive effects of these factors on competition and predation by a dragonfly larva (Anax junius) and fish predator (Lepomis cyanallus). When inter-patch distances (FHC) were short, A. junius consumed more amphipods (36% +/- 4.6%) compared with long treatments (19% +/- 4.8%). We detected no significant effects of plant density (SHC) on prey consumption by A. junius. There were significant interactive effects of FHC and SHC on Lepomis cyanellus consumption of amphipods and damselflies. The most counterintuitive of these effects was that sunfish consumed more larval damselflies at high plant density (64% +/- 6.0%) than at low plant density (38% +/- 8.6%) but only in short connection treatments. This interactive effect of SHC and FHC on damselfly predation by L. cyanellus was likely because damselflies exhibited riskier behavior at higher SHC. Prey consumption with both predators present was additive, but no significant effect of either SHC or FHC on interspecific predation was detected, suggesting compensatory foraging responses. Structural habitat complexity and FHC interactively influence predator foraging behavior in complex, non-intuitive ways that are highly dependent on the predator/prey combination in question. Structural habitat complexity and FHC are currently being influenced by anthropogenic factors in multiple ways (e.g., habitat loss, global climate change), and being able to predict the responses of biotic communities to thes

关键词： Anax junius functional habitat connectivity habitat structure inter-patch distance Lepomis cyanellus multiple predator spatial complexity structural complexity

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Open data and open source for remote sensing training in ecology

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ECOLOGICAL INFORMATICS 2017年 40卷 57-61页

作者： Rocchini, Duccio Petras, Vaclav Petrasova, Anna Horning, Ned Furtkevicova, Ludmila Neteler, Markus Leutner, Benjamin Wegmann, Martin Univ Trento Ctr Agr Food Environm Via E Mach 1 I-38010 San Michele All Adige TN Italy Univ Trento Ctr Integrat Biol Via Sommarive 14 I-38123 Povo TN Italy Fdn Edmund Mach Dept Biodivers & Mol Ecol Res & Innovat Ctr Via E Mach 1 I-38010 San Michele All Adige TN Italy North Carolina State Univ Dept Marine Earth & Atmospher Sci 2800 Faucette Dr Raleigh NC 27695 USA North Carolina State Univ Ctr Geospatial Analyt 2800 Faucette Dr Raleigh NC 27695 USA Amer Museum Nat Hist Ctr Biodivers & Conservat New York NY 10024 USA Mundialis GmbH & Co KG Koelnstr 99 D-53111 Bonn Germany Univ Wurzburg Dept Remote Sensing Oswal Kuelpe Weg 86 D-97074 Wurzburg Germany

Remote sensing is one of the most important tools in ecology and conservation for an effective monitoring of ecosystems in space and time. Hence, a proper training is crucial for developing effective conservation practices based on remote sensing data. In this paper we aim to highlight the potential of open access data and open source software and the importance of the inter-linkages between these and remote sensing training, with an interdisciplinary perspective. We will first deal with the importance of open access data and then we provide several examples of Free and Open Source Software (FOSS) for a deeper and more critical understanding of its application in remote sensing.

关键词： Education Free and Open Source Software Remote sensing spatial complexity spatial ecology

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