Distinct Patches Research Articles

TPT-Dance&Actions : un corpus multimodal d’activités humaines

TPT-Dance&Actions : un corpus multimodal d’activités humaines

A new Bagrid catfish species, Rita bakalu (Siluriformes: Bagridae), from the Godavari River basin, India

Rita bakalu, a new species, is described from the Godavari river system in peninsular India. With this finding, the genus Rita is enlarged to include seven species, comprising six species found in South Asia, R. rita, R. macracanthus, R. gogra, R. chrysea, R. kuturnee, R. bakalu, and one species R. sacerdotum from Southeast Asia. R. bakalu is distinguished from its congeners by a combination of the following characters: eye diameter 28–39% HL and 20–22 caudal fin rays; teeth in upper jaw uniformly villiform in two patches, interrupted at the midline; palatal teeth well-developed villiform, in two distinct patches located at the edge of the palate. The mtDNA cytochrome C oxidase I sequence analysis confirmed that the R. bakalu is distinct from the other congeners of Rita. Superficially, R. bakalu resembles R. kuturnee, reported from the Godavari and Krishna river systems; however, the two species are discriminated due to differences in the structure of their teeth patches on upper jaw and palate, anal fin originating before the origin of adipose fin, comparatively larger eye diameter, longer mandibular barbels, and vertebral count. The results conclude that the river Godavari harbors a different species of Rita, R. bakalu which is new to science.

Stability and complexity in model meta-ecosystems.

The diversity of life and its organization in networks of interacting species has been a long-standing theoretical puzzle for ecologists. Ever since May's provocative paper challenging whether ‘large complex systems [are] stable' various hypotheses have been proposed to explain when stability should be the rule, not the exception. Spatial dynamics may be stabilizing and thus explain high community diversity, yet existing theory on spatial stabilization is limited, preventing comparisons of the role of dispersal relative to species interactions. Here we incorporate dispersal of organisms and material into stability–complexity theory. We find that stability criteria from classic theory are relaxed in direct proportion to the number of ecologically distinct patches in the meta-ecosystem. Further, we find the stabilizing effect of dispersal is maximal at intermediate intensity. Our results highlight how biodiversity can be vulnerable to factors, such as landscape fragmentation and habitat loss, that isolate local communities.

Effect of fish oil on lateral mobility of prostaglandin F2α (FP) receptors and spatial distribution of lipid microdomains in bovine luteal cell plasma membrane in vitro

Lipid microdomains are ordered regions on the plasma membrane of cells, rich in cholesterol and sphingolipids, ranging in size from 10 to 200 nm in diameter. These lipid-ordered domains may serve as platforms to facilitate colocalization of intracellular signaling proteins during agonist-induced signal transduction. It is hypothesized that fish oil will disrupt the lipid microdomains, increasing spatial distribution of these lipid-ordered domains and lateral mobility of the prostaglandin (PG) F2α (FP) receptors in bovine luteal cells. The objectives of this study were to examine the effects of fish oil on (1) the spatial distribution of lipid microdomains, (2) lateral mobility of FP receptors, and (3) lateral mobility of FP receptors in the presence of PGF2α on the plasma membrane of bovine luteal cells in vitro. Bovine ovaries were obtained from a local abattoir and corpora lutea were digested using collagenase. In experiment 1, lipid microdomains were labeled using cholera toxin subunit B Alexa Fluor 555. Domains were detected as distinct patches on the plasma membrane of mixed luteal cells. Fish oil treatment decreased fluorescent intensity in a dose-dependent manner (P < 0.01). In experiment 2, single particle tracking was used to examine the effects of fish oil treatment on lateral mobility of FP receptors. Fish oil treatment increased microdiffusion and macrodiffusion coefficients of FP receptors as compared to control cells (P < 0.05). In addition, compartment diameters of domains were larger, and residence times were reduced for receptors in fish oil–treated cells (P < 0.05). In experiment 3, single particle tracking was used to determine the effects of PGF2α on lateral mobility of FP receptors and influence of fish oil treatment. Lateral mobility of receptors was decreased within 5 min following the addition of ligand for control cells (P < 0.05). However, lateral mobility of receptors was unaffected by addition of ligand for fish oil–treated cells (P > 0.10). The data presented provide strong evidence that fish oil causes a disruption in lipid microdomains and affects lateral mobility of FP receptors in the absence and presence of PGF2α.

Solution structure of the microtubule-targeting COS domain of MID1.

The human MID1 protein is required for the proper development during embryogenesis. Mutations of MID1 are associated with X-linked Opitz G syndrome, characterized by midline anomalies. MID1 associates with the microtubules and functions as an ubiquitin E3 ligase, targeting protein phosphatase 2A for ubiquitin-mediated regulation. The mechanism of microtubule association is not known. Recently, a 60-amino acid region termed the C-terminal subgroup One Signature (COS) box/domain was identified at the C-terminal end of the coiled-coil (CC) domain that facilitates microtubule localization. Insertion of the MID1 COS domain at the C-terminal end of the CC domain of a nonmicrotubule-associated TRIM protein confers microtubule localization. Here, we report the solution structure of the COS domain of MID1. The domain adopts a helix-loop-helix structure in which the N- and C-terminal ends are in close proximity. Hydrophobic residues stabilizing the interaction of the two α-helices form a central hydrophobic core. The loop separating the α-helices is structured, with two of its hydrophobic residues making contact with the central core. On the outer surface, positively charged residues form a distinct basic patch near the termini that we postulate is important for microtubule binding. A model of the structure of the preceding coiled-coil and COS domains (CC-COS) show that the COS domain forms a helical bundle at the C-terminal end of the CC domain similar to the spectrin-like fold observed with some known microtubule-binding proteins. Interestingly, the CC-COS domains bind to microtubules, demonstrating for the first time that MID1 can directly associate with the microtubules. Structural data are available in PDB database under the accession number 5IM8.

Fires of differing intensities rapidly select distinct soil fungal communities in a Northwest US ponderosa pine forest ecosystem

Environmental change and long-term fire management in the western United States have created conditions that facilitate high-intensity burn areas in forested systems. Such burns may have dramatic effects on the soil microbial communities. In this study, we utilized experimental infrastructure in the Pringle Falls Experimental Forest in Oregon, where ten pairs of sites were assigned to either high burn (HB) or low burn (LB) intensity treatments to examine fungal community responses. In these treatments, understory shrubs and logging debris were masticated and broadcast burned (LB) or piled logs were fully combusted (HB) in a paired design. The burn treatments generated soil temperatures of ∼100°C (LB) or up to 700°C (HB) at the soil surface. We sampled soils (0–10cm) one week before and three weeks after ignition and Illumina MiSeq-analyzed fungal Internal Transcribed Spacer 1 (ITS1) PCR-amplicons to deeply dissect the fungal communities. Our data indicate dramatic and rapid responses in community diversity and evenness in the HB treatment, with similar responses, but to a lesser degree, in the LB treatment. Nonmetric Multidimensional Scaling (NMS) ordinations and analyses of taxon frequencies reveal a substantial community turnover and corresponding replacement of the dominant basidiomycetes by ascomycetes in the HB treatment. Similar trends were visible, but weaker in the LB treatments. These coarse-level taxonomic responses were attributable to a few fire-responsive fungi, particularly Operational Taxonomic Units (OTUs) assigned to Pyronema sp. and Morchella sp., whose frequencies increased more than 100-fold following the HB treatment. Our study highlights the strong and rapid fungal fire responses and differences among fires of different intensities. As the high intensity fires – such as those represented here by the HB treatment – tend to be spatially confined and limited in scale, we emphasize their potential to generate distinct patches that may substantially contribute to beta diversity on small scales. Further, these data lead to questions about fungal community recovery (return to community state preceding the fire) and the importance of patch dynamics following a fire as well as function of post-fire communities and ecosystem services that they may provide.

Hydrophobin-1 promotes thermostability of firefly luciferase.

The thermal sensitivity of firefly luciferase limits its use in certain applications. Firefly luciferase has hydrophobic sites on its surface, which lead to aggregation and inactivation of the enzyme at temperatures over 30 °C. We have successfully stabilized firefly luciferase at high temperatures with the assistance of a unique protein, hydrophobin-1 (HFB1). HFB1 is a small secretory protein belonging to class II of hydrophobins with a low molecular weight (7.5 kDa) and distinct functional hydrophobic patch on its surface. The interaction of HFB1 with hydrophobic sites on the surface of luciferase was confirmed by extrinsic fluorescence studies using 8-anilino-1-naphthalenesulfonic acid (ANS) as a hydrophobic reporter probe. Calculation of thermodynamic parameters of heat inactivation of luciferase shows that conformational changes and flexibility of enzyme decreased in the presence of HFB1, and thermostability of the HFB1-treated enzyme increased. Furthermore, the addition of HFB1 into the enzymatic solution leads to an increase in catalytic efficiency of luciferase and subsequently improves the utility of the enzyme as an ATP detector.

Identifying Kittlitz's Murrelet Nesting Habitat in North America at the Landscape Scale

AbstractThe Kittlitz's murrelet Brachyramphus brevirostris is a small, noncolonial seabird endemic to marine waters of Alaska and eastern Russia that may have experienced significant population decline in recent decades, in part because of low reproductive success and terrestrial threats. Although recent studies have shed new light on Kittlitz's murrelet nesting habitat in a few discrete areas, the location and extent of suitable nesting habitat throughout most of its range remains unclear. Here, we have compiled all existing nest records and locations to identify landscape-scale parameters (distance to coast, elevation, slope, and land cover) that provide potential nesting habitat in four regions: northern Alaska, Aleutian Islands, Alaska Peninsula Mountains and Kodiak Island, and Pacific Coastal Mountains (including nearshore interior Canada). We produced a final map classifying 12% (70,411 km2) of the lands assessed as potential Kittlitz's murrelet nesting habitat, with dense but distinct patches in northern Alaska and a more uninterrupted, narrow band extending across the Pacific Coastal Mountains, Alaska Peninsula Mountains, and Aleutian Islands. The extent of habitat-capable parameter values varied regionally, indicating that the Kittlitz's murrelet may be able to use a variety of habitats for nesting, depending on availability. Future nesting habitat studies could employ spatially random sampling designs to allow for quantitatively robust modeling of nesting habitat and predictive extrapolation to areas where nests have not been located but likely exist.

Face super resolution based on parent patch prior for VLQ scenarios

Face Super Resolution (FSR) is to infer High Resolution (HR) facial images from given Low Resolution (LR) ones with the assistance of LR and HR training pairs. Among existing methods, Neighbor Embedding(NE) FSR methods are superior in visual and objective quality than holistic based methods. These NE methods are based on the consistency assumption that the neighbors in HR/LR space form similar local geometry. But when LR images are in Very Low Quality (VLQ), the LR patches are seriously contaminated that even two distinct patches form similar appearance, which means that the consistency assumption is not well held anymore. To solve this problem, in this paper we use the target patch as well as the surrounding pixels, which we call parent patch, to represent the target patch. By incorporating the peripheral information, the parent patch is much more robust to noise in the LR and HR consistency learning. The effectiveness of proposed method is verified both quantitatively and qualitatively. In this paper, we also discuss the boundary and the paradox of the multi-scaled parent patch prior in NE based FSR framework.

Major disruption of D″ beneath Alaska

AbstractD″ represents one of the most dramatic thermal and compositional layers within our planet. In particular, global tomographic models display relatively fast patches at the base of the mantle along the circum‐Pacific which are generally attributed to slab debris. Such distinct patches interact with the bridgmanite (Br) to post‐bridgmanite (PBr) phase boundary to generate particularly strong heterogeneity at their edges. Most seismic observations for the D″ come from the lower mantle S wave triplication (Scd). Here we exploit the USArray waveform data to examine one of these sharp transitions in structure beneath Alaska. From west to east beneath Alaska, we observed three different characteristics in D″: (1) the western region with a strong Scd, requiring a sharp δVs = 2.5% increase; (2) the middle region with no clear Scd phases, indicating a lack of D″ (or thin Br‐PBr layer); and (3) the eastern region with strong Scd phase, requiring a gradient increase in δVs. To explain such strong lateral variation in the velocity structure, chemical variations must be involved. We suggest that the western region represents relatively normal mantle. In contrast, the eastern region is influenced by a relic slab that has subducted down to the lowermost mantle. In the middle region, we infer an upwelling structure that disrupts the Br‐PBr phase boundary. Such an interpretation is based upon a distinct pattern of travel time delays, waveform distortions, and amplitude patterns that reveal a circular‐shaped anomaly about 5° across which can be modeled synthetically as a plume‐like structure rising about 400 km high with a shear velocity reduction of ~5%, similar to geodynamic modeling predictions of upwellings.

Mouthparts and nectar feeding of the flower visiting cricket Glomeremus orchidophilus (Gryllacrididae)

Glomeremus orchidophilus (Gryllacrididae) is a flower visiting cricket on the tropical island La Réunion. This species is the only Orthoptera shown to be a pollinator of a plant. We studied its nectar feeding behavior and mouthpart morphology in detail. Since G. orchidophilus possesses biting-and-chewing mouthparts, our objective was to find behavioral and/or structural specializations for nectar-feeding. The comparative analysis of feeding behavior revealed that fluid is taken up without movements of the mouthparts in Glomeremus. A comparative morphological examination of two Glomeremus species, together with several representatives of other Gryllacrididae and other Ensifera taxa revealed subtle adaptations to fluid feeding in Glomeremus. All representatives of Gryllacrididae were found to possess a distinct patch of microtrichia at the tip of their galeae. However, in Glomeremus a channel is formed between the distal components of the maxillae and the mandibles on each side of the body. Micro-CT and SEM examination revealed a longitudinal groove that extends over the galea beginning at the patch of microtrichia in the studied Glomeremus species. We hypothesize that the microtrichia take up fluid by capillarity and the action of the cibarium and pharyngeal pumps transports fluid along the channels between the maxillae and mandibles into the preoral cavity. These mouthpart features allow nectar uptake from flowers that is unique in Orthoptera.

Species presence frequency and diversity in different patch types along an altitudinal gradient: Larix chinensis Beissn in Qinling Mountains (China).

Forest communities are mosaic systems composed of patches classified into four different developmental patch types: gap patch (G), building patch (B), mature patch (M) and degenerate patch (D). To study the mechanisms maintaining diversity in subalpine coniferous forests, species presence frequency and diversity in the four distinct patch types (G, B, M and D) of Larix chinensis conifer forests at three altitudinal gradients in the Qinling Mountains were analyzed. Our results were as follows: (1) Different species (or functional groups) had distinct presence frequencies in the four different patch types along the altitudinal gradient; (2) Some species or functional groups (species groups sharing similar traits and responses to the environment) only occurred in some specific patches. For seed dispersal, species using wind mainly occurred in G and D, while species using small animals mainly occurred in B and M; (3) Species composition of adjacent patch types was more similar than non-adjacent patch types, based on the lower β diversity index of the former; (4) The maximum numbers of species and two diversity indices (D′ and H′) were found in the middle altitudes. Various gap-forming processes and dispersal limitation may be the two major mechanisms determining species diversity in Larix chinensis coniferous forests at the patch scale.

Modeling metapopulation dynamics of HIV epidemic on a linear lattice with nearest neighbour coupling

&lt;p&gt;Many mathematical models for the spread of infectious diseases in a population assume homogeneous mixing, but due to spatial distribution, there exist distinct patches with unique disease dispersion dynamics, especially if between patch mixing due to travel and migration is limited. In this paper, three levels of disease status in a - patch metapopulation was studied using a simple SIR-HIV epidemic model in a one dimensional nearest neighbour coupling lattice. The basic reproductive ratio , which is a function of coupling strength , is shown to affect stability characteristics of equilibrium points. The disease free equilibrium (DFE) is globally asymptotically stable irrespective of the value of but the stability of the endemic equilibrium point (EEP) depends on the coupling strength . It was found that at the critical value of coupling strength , the subpopulations dynamics are synchronized while for the subpopulation dynamics are independent. Patch isolation strategy for the control of HIV dispersion requires a critical coupling strength of . This interaction restriction reduces to values less than one, and the disease will be eliminated, making isolation effective. Demographic and epidemiological parameters of Vihiga County in Kenya were used in the study.&lt;/p&gt;

Bee Abundance and Nutritional Status in Relation to Grassland Management Practices in an Agricultural Landscape.

Grasslands provide important resources for pollinators in agricultural landscapes. Managing grasslands with fire and grazing has the potential to benefit plant and pollinator communities, though there is uncertainty about the ideal approach. We examined the relationships among burning and grazing regimes, plant communities, and Bombus species and Apis mellifera L. abundance and nutritional indicators at the Grand River Grasslands in southern Iowa and northern Missouri. Treatment regimes included burn-only, grazed-and-burned, and patch-burn graze (pastures subdivided into three temporally distinct fire patches with free access by cattle). The premise of the experimental design was that patch-burn grazing would increase habitat heterogeneity, thereby providing more diverse and abundant floral resources for pollinators. We predicted that both bee abundance and individual bee nutritional indicators (bee size and lipid content) would be positively correlated with floral resource abundance. There were no significant differences among treatments with respect to bee abundance. However, some of the specific characteristics of the plant community showed significant relationships with bee response variables. Pastures with greater abundance of floral resources had greater bee abundance but lower bee nutritional indicators. Bee nutritional variables were positively correlated with vegetation height, but, in some cases, negatively correlated with stocking rate. These results suggest grassland site characteristics such as floral resource abundance and stocking rate are of potential importance to bee pollinators and suggest avenues for further research to untangle the complex interactions between grassland management, plant responses, and bee health.

A novel face super resolution approach for noisy images using contour feature and standard deviation prior

Face Super Resolution (FSR) is to infer high resolution (HR) face images from given low resolution (LR) face images with the help of HR/LR training examples. The most representative FSR is NE methods, which are based on the consistency assumption that the HR/LR patch pairs form similar local geometric structures. But NE methods have difficulty in dealing with noisy facial images. The reason lies in the wrong neighborhood relationship caused by low quality scenarios that even two distinct patches have similar relation in local geometry. Therefore, the consistency assumption is not well held anymore. This paper presents a novel FSR approach suitable for noisy facial images. Our work are twofold. Firstly, different from the existing methods which directly enhance the noisy input image in intensity feature space, the proposed method introduces a contour feature which is robust to noise. By applying the contour feature as constraint, the noise effects can be effectively suppressed. Secondly, different from the existing methods which directly constrain the noisy input image with low quality contour feature, a standard deviation prior is proposed to enhance the low quality contour feature. Through enhancing the contour feature into high quality, the FSR reconstruction can be better constrained. Both simulation and the real-world scenario experiments demonstrate that the proposed approach outperforms most classic methods both quantitatively and qualitatively.

Detection and spatiotemporal analysis of methane ebullition on thermokarst lake ice using high-resolution optical aerial imagery

Abstract. Thermokarst lakes are important emitters of methane, a potent greenhouse gas. However, accurate estimation of methane flux from thermokarst lakes is difficult due to their remoteness and observational challenges associated with the heterogeneous nature of ebullition. We used high-resolution (9–11 cm) snow-free aerial images of an interior Alaskan thermokarst lake acquired 2 and 4 days following freeze-up in 2011 and 2012, respectively, to detect and characterize methane ebullition seeps and to estimate whole-lake ebullition. Bubbles impeded by the lake ice sheet form distinct white patches as a function of bubbling when lake ice grows downward and around them, trapping the gas in the ice. Our aerial imagery thus captured a snapshot of bubbles trapped in lake ice during the ebullition events that occurred before the image acquisition. Image analysis showed that low-flux A- and B-type seeps are associated with low brightness patches and are statistically distinct from high-flux C-type and hotspot seeps associated with high brightness patches. Mean whole-lake ebullition based on optical image analysis in combination with bubble-trap flux measurements was estimated to be 174 ± 28 and 216 ± 33 mL gas m−2 d−1 for the years 2011 and 2012, respectively. A large number of seeps demonstrated spatiotemporal stability over our 2-year study period. A strong inverse exponential relationship (R2 &gt; = 0.79) was found between the percent of the surface area of lake ice covered with bubble patches and distance from the active thermokarst lake margin. Even though the narrow timing of optical image acquisition is a critical factor, with respect to both atmospheric pressure changes and snow/no-snow conditions during early lake freeze-up, our study shows that optical remote sensing is a powerful tool to map ebullition seeps on lake ice, to identify their relative strength of ebullition, and to assess their spatiotemporal variability.

Peptide Selectivity of the Proton-Coupled Oligopeptide Transporter from Neisseria meningitidis

Peptide transport in living organisms is facilitated by either primary transport, hydrolysis of ATP, or secondary transport, cotransport of protons. In this study, we focused on investigating the ligand specificity of the Neisseria meningitidis proton-coupled oligopeptide transporter (NmPOT). It has been shown that the gene encoding this transporter is upregulated during infection. NmPOT conformed to the typical chain length preference as observed in prototypical transporters of this family. In contrast to prototypical transporters, it was unable to accommodate a positively charged peptide residue at the C-terminus position of the substrate peptide. Sequence analysis of the active site of NmPOT displayed a distinctive aromatic patch, which has not been observed in any other transporters from this family. This aromatic patch may be involved in providing NmPOT with its atypical preferences. This study provides important novel information towards understanding how these transporters recognize their substrates.

Erratum to: Habitat fragmentation and biodiversity conservation: key findings and future challenges

Landscape Ecol DOI 10.1007/s10980-015-0312-3 EDITORIAL Habitat fragmentation and biodiversity conservation: key findings and future challenges Maxwell C. Wilson . Xiao-Yong Chen . Richard T. Corlett . Raphael K. Didham . Ping Ding . Robert D. Holt . Marcel Holyoak . Guang Hu . Alice C. Hughes . Lin Jiang . William F. Laurance . Jiajia Liu . Stuart L. Pimm . Scott K. Robinson . Sabrina E. Russo . Xingfeng Si . David S. Wilcove . Jianguo Wu . Mingjian Yu Received: 5 November 2015 / Accepted: 7 November 2015 Springer Science+Business Media Dordrecht 2015 Habitat loss and fragmentation has long been consid- ered the primary cause for biodiversity loss and ecosystem degradation worldwide, and is a key research topic in landscape ecology (Wu 2013). Habitat fragmentation often refers to the reduction of continuous tracts of habitat to smaller, spatially distinct remnant patches, and habitat loss typically occurs concurrently with habitat fragmentation (Col- linge 2009). Although some habitats are naturally patchy in terms of abiotic and biotic conditions (Wu and Loucks 1995), human actions have profoundly fragmented landscapes across the word (Haddad et al. 2015), altering the quality and connectivity of habitats. Therefore, understanding the causes and conse- quences of habitat fragmentation is critical to preserv- ing biodiversity and ecosystem functioning. From May 4th to 10th, 2015, an International Workshop on Habitat Fragmentation and Biodiversity Conservation, held at the Thousand Island Lake, Zhejiang, China, discussed threats to biodiversity in fragmented landscapes and how fragmentation research can identify and help mitigate these threats. M. C. Wilson J. Wu School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA e-mail: mcwilso2@gmail.com P. Ding (&) J. Liu X. Si M. Yu (&) College of Life Sciences & Institute of Ecology, Zhejiang University, Hangzhou 310058, Zhejiang, China e-mail: dingping@zju.edu.cn X.-Y. Chen School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200214, China R. T. Corlett A. C. Hughes Centre for Integrative Conservation, Xishuangbanna Tropical Botanic Garden, Chinese Academy of Sciences, Menglun, Mengla 666303, Yunnan, China R. K. Didham School of Animal Biology, University of Western Australia, Perth, WA 6009, Australia R. K. Didham CSIRO Land and Water, Centre for Environment and Life Sciences, Perth, WA 6014, Australia M. Yu e-mail: fishmj202@hotmail.com R. D. Holt Department of Biology, University of Florida, Gainesville, FL 32611, USA M. Holyoak Department of Environmental Science and Policy, University of California, Davis, CA 95616, USA G. Hu Department of Landscape Architecture, School of Civil Engineering and Architecture, Zhejiang University of Science and Technology, Hangzhou 310018, Zhejiang, China

Differentiation of the biogeochemical niches of legumes and non-legumes in the Cape Floristic Region of South Africa

Many legume species in the Cape Floristic Region, recently renamed the Core Cape Subregion (CCR), occur in distinct population patches within the landscape. We hypothesized that when compared to non-legumes, legumes occupy a distinct nutrient-enriched biogeochemical niche, and that foliar nutrient concentrations would correspond with soil chemistry. Soil and leaf samples were collected at eight sites in the CCR that were selected based on soil types including limestone-, sandstone-, granite- and sand-derived soils. At each site, samples were collected along three parallel replicate line transects originating inside the legume patch and extending into the adjacent non-legume habitat. The soil and plant samples were processed and analysed for chemical elements. Within a soil type, canonical discriminant analysis of soil nutrient concentrations separated legume from non-legume habitats on limestone, sandstone and granitic soils, thereby identifying their biogeochemical niche. Multiple nutrients were associated with the legume niche, and the nutrients varied with soil type. Relative to the non-legume habitat, the legume habitat was enriched with nutrients with greater concentrations of total N, total P, K, Mg, Na and C in both limestone and sandstone soils, but only enriched with C in granitic soil. Furthermore, a strong canonical correlation in both legume and non-legume plants (e.g. along CV1 r = 0.90 and 0.83, respectively) was found between the soil and leaf nutrients. Overall, the study provided empirical evidence for the existence of a nutrient-rich biogeochemical niche for legumes in the CCR and showed that foliar nutrients reflected soil chemistry.

Habitat fragmentation and biodiversity conservation: key findings and future challenges

Habitat loss and fragmentation has long been considered the primary cause for biodiversity loss and ecosystem degradation worldwide, and is a key research topic in landscape ecology (Wu 2013). Habitat fragmentation often refers to the reduction of continuous tracts of habitat to smaller, spatially distinct remnant patches, and habitat loss typically occurs concurrently with habitat fragmentation (Collinge 2009). Although some habitats are naturally patchy in terms of abiotic and biotic conditions (Wu and Loucks 1995), human actions have profoundly fragmented landscapes across the word (Haddad et al. 2015), altering the quality and connectivity of habitats. Therefore, understanding the causes and consequences of habitat fragmentation is critical to preserving biodiversity and ecosystem functioning. From May 4th to 10th, 2015, an International Workshop on Habitat Fragmentation and Biodiversity Conservation, held at the Thousand Island Lake, Zhejiang, China, discussed threats to biodiversity in fragmented landscapes and how fragmentation research can identify and help mitigate these threats. To meet these challenges, the Workshop had three goals. The first was to synthesize key findings in fragmentation science. Second was to identify important remaining research questions concerning the relationships between habitat fragmentation, biodiversity, and ecosystem functioning at local, regional, and global scales. Finally, we examined the unique roles of field-based fragmentation experiments in addressing these questions. The Workshop’s findings are relevant to the broader ecological community, and we present them here to stimulate research that will advance landscape ecology and conservation biology.