High Variability Research Articles

Temporal trajectories of plant functional traits in mediterranean grasslands under different grazing regimes

AbstractAimsMediterranean grasslands are semi‐natural ecosystems that have been affected by land‐use intensification and abandonment during the past decades. Adaptative multi‐paddock grazing regimes, where grazing alternates with long periods of vegetation recovery, have been proposed as a more biodiversity‐friendly management compared with continuous grazing. This study aimed to compare the effect of these two different grazing regimes on a set of plant traits in mediterranean grassland vegetation over time.LocationCentral part of Sardinia (Italy) at 350 m a.s.l. in a permanent grassland system.MethodsWe applied the point quadrat method to quantify the specific contribution of each species along permanent transects in spring and winter from 2018 to 2022. We considered the following plant traits: leaf dry matter content, life forms, flowering start and length of flowering. Overall, we performed 128 surveys and measured traits for 61 species. We ran a linear mixed model to test the effect of season, grazing regimes and years on functional diversity and community‐weighted mean for single traits.ResultsAdaptative multi‐paddock regimes over time increased the leaf dry matter content. However, compared with grazing regimes, seasonality through time had the greatest effect on flowering traits and life forms.ConclusionThe relatively small variation in the plant traits suggests that the mediterranean grassland was rather stable despite wide variation in grazing regimes, probably linked to their long history of human association. Nonetheless, adaptative multi‐paddock regimes may have higher beneficial effects compared with continuous grazing, favouring more palatable species and improving soil fertility. By contrast, the high variation in the plant traits over time suggests a high vulnerability of the same grassland to climatic changes.

Multi-Resolution Wavelet Fractal Analysis and Subtask Training for Enhancing Few-Shot Noisy Brainwave Recognition.

The integration of healthcare monitoring with Internet of Things (IoT) networks radically transforms the management and monitoring of human well-being. Portable and lightweight electroencephalography (EEG) systems with fewer electrodes have improved convenience and flexibility while retaining adequate accuracy. However, challenges emerge when dealing with real-time EEG data from IoT devices due to the presence of noisy samples, which impedes improvements in brainwave detection accuracy. Moreover, high inter-subject variability and substantial variability in EEG signals present difficulties for conventional data augmentation and subtask learning techniques, leading to poor generalizability. To address these issues, we present a novel framework for enhancing EEG-based recognition through multi-resolution data analysis, capturing features at different scales using wavelet fractals. The original data can be expanded many times after continuous wavelet transform (CWT) and recombination, alleviating insufficient training samples. In the transfer stage of deep learning (DL) models, we adopt a subtask learning approach to train the recognition model to generalize efficiently. This incorporates wavelets at various scales instead of exclusively considering average prediction performance across scales and paradigms. Through extensive experiments, we demonstrate that our proposed DL-based method excels at extracting features from small-scale and noisy EEG data. This significantly improves healthcare monitoring performance by mitigating the impact of noise introduced by the external environment.

Variabilidade patológica e genética de isolados bacterianos causadores de podridão mole em hortaliças na região oeste do Pará, Brasil

ABSTRACT: Seventy-five pectinolytic strains collected from vegetables grown in the counties of Santarém, Belterra, and Mojuí dos Campos, located in the western region of the Pará State, Brazil, were studied according to their pathological and genetic variability. The strains were grouped in 5 clusters according to pathogenicity in potato, pepper, carrot, and onion, and 38 strains were selected for genetic analysis using rep-PCR. These strains were divided into 35 genetic groups according to rep-PCR at 70% similarity. These results indicated high pathological and genetic variability of the strains causing soft rot in vegetables in the western region of the Pará State, which will be used in etiological research and for the development and assessment of management techniques for the soft rot in vegetables in this region.

Short- and long-term reproducibility of body surface gastric mapping using the Gastric Alimetry® system.

Many diagnostic tests for gastroduodenal symptoms, such as gastric emptying scintigraphy (GES), gastric emptying breath tests (GEBT), and electrogastrography (EGG) show variable intra-individual reproducibility over time. This study investigated the short- and long-term reproducibility of body surface gastric mapping (BSGM), a non-invasive test for assessing gastric function, in controls and patients with chronic gastroduodenal disorders. Participants completed three standardized BSGM tests using Gastric Alimetry® (Alimetry, New Zealand). The test encompassed a fasting baseline (30 min), a 482 kCal standard meal, and a 4 h postprandial recording. The first two tests were >6 months apart and the last occurred ~1 week after the second test, to evaluate long and short-term reproducibility. Fourteen patients with upper gastrointestinal symptoms and 14 healthy controls were recruited. There were no significant differences in any BSGM metrics between the tests at short and long term (all p > 0.180). Lin's concordance correlation coefficients (CCC) for the primary metrics were high, ranging from 0.58 to 0.96, with intra-individual coefficients of variance (CVintra) ranging from 0.2% to 1.9%. Reproducibility was higher, and intra-individual variation lower, than in previous studies of GES (CCC = 0.54-0.83, CVintra = 3%-77%), GEBT (CVintra = 8%-11%), and EGG (CVintra = 3%-78%). BSGM spectral metrics demonstrate high reproducibility and low intra-individual variation at both short and long term, with superior results to comparable tests. The high reproducibility of Gastric Alimetry supports its role as a diagnostic aid for gastric dysfunction and a reliable tool for evaluating treatment outcomes and disease progression over time.

Assessing the Impact of Gas Flaring Activities in Ebedei, Southern Nigeria

The study looked at how gas flaring affects development and sustainable growth. While the availability of natural gas and crude oil is expected to serve as a socioeconomic stimulus for faster, more sustainable growth, the current situation in Nigeria's oil-producing regions is significantly worse than expected. Eleven (11) experimental locations, including Obinomba (control site), which lacks a gas flaring station, provide data for the collections. The air quality indices concentrations and various temperatures were measured. At a starting location that was 50 meters distant from the flare's bund wall, assessments of the location temperature and also air quality in Ebedei were taken at intervals of 50 meters. The statistics indicate that both the temperature and the quantity (content) of gases (CO, NO2, SO4, and CH4) have increased. Thus, a rise in temperature is proportional to a rise in flared gases. It is imperative that no agricultural crops be planted in this area that react adversely to high temperature variation, such as cassava, palm trees, rubber trees, bananas, and other crops. It can be suggested that the extracted gas be liquefied and bottled for usage in home and industrial settings, as well as being heavily utilized by a gas turbine to generate electricity. Residential buildings should be constructed at least 0.5 kilometers away from the flare point, and water samples should be analyzed to determine the level of contamination and water portability. To maintain adherence and keep the blessed environment, it is totally crucial to urge that FEPA continuously track and assess the degree of damages attributed to gas flaring.

Chichimene field T2 sand: a successful application of cycles in a water injection project on heavy crude oil, enabled by a novel smart selective completion system adapted for water injection

This paper presents the application of injection in cycles, assisted by the first smart selective completion system with remote valve operation. The completion system was installed in the Chichimene Field unit T2 (Fm. San Fernando). The results were compared with conventional water injection, technology that utilizes a simple selective completion system, in the aspects of recovery factor, water consumption, operation style, and others. The target unit has been subjected to selective water injection since 2016, this process consisted of injection of a controlled amount of water within 3-4 zones in equilibrium with the extractive system on producers wells to find a better crude oil movement and a commercial recovery factor. Despite this, the surveillance evidence suggests that some zones consume too much water due its high permeability (heterogeneity) and this impacts on high water cut on producers due to the (adverse mobility ratio), but also suggested that there is a better way to improve even more the recovery factor. This enhancement was enabled with a smart selective completion system by promoting a scheduled temporal closure of zones while production continues, achieving pressure-production restoration effects on the closed zones, allowing an efficiency increase of the vertical and areal sweep. To determine if this could work, a smart completion system was installed in one well in August 2019. During more than one year, the operation and interpretation of the DAS measuring tool (Continuous sound recording) was understood, from which injected water per zone is daily known, with this, the optimization of the injection rate per zone allowed enhancement of the production pattern behaviour. In February 2021, the injection cycles started on the well by zone, and to the current date, more than 25 monthly cycles have been done, increasing the recovery factor, with a considerable reduction in water and energy consumption, maintaining a continuous measurement of zone injection, this level of information has never been reached in the industry. The case study establishes a new frontier in the field of selective injection and in cycles as well, allowing an evolution step in water injection technology. This pilot combined in one design: selective injection, intelligent remote operate completions, continuous layer injection measuring by DAS, extra heavy oil WF, management of high permeability variations and it is aligned with the latest regulations in decarbonization (water and energy saving). From a reservoir point of view, it has never been there, a surveillance in injectors with this level of quality to enhance performance, and on the surface, this technology has allowed an important reduction in the use of wirelines for well operations and improve some well cleaning interventions with coiled tubing.

Microbial Communities Associated with the Intestinal Tract of Grey Mullets from a Mediterranean Aquatic Environment

Introduction: Grey mullets comprise different species that represent the most ubiquitous teleost families in the planet’s coastal waters. They are an important proportion of the Mediterranean lagoon’s production and have been recently considered cultivated marine fish. This study aimed to explore the intestinal microbial communities of grey mullets to understand their possible ecological role for fish and the aquatic environment. Methods: Thirty-four wild-caught mullets were sampled from a Mediterranean lagoon during four seasons and the V3-V4 hypervariable regions of 16S rRNA (Illumina MiSeq) of the fish gut were sequenced. Parameters of the aquatic environment were detected: temperature, salinity, DO, PO4, NH4, NO3, NO2, SiO, DIN, and Chla. Results: The results indicated a high bacterial diversity (mean Shannon index: 4.74 ± 1.12; Simpson index: 0.93 ± 0.08) and variations among seasons. Sixty prokaryotic phyla were identified and the most abundant ones were: Proteobacteria (mean relative abundance 35.4% ± 17.9), Actinobacteriota (mean relative abundance 16.4% ± 9.9), and Firmicutes (mean relative abundance 10.1% ± 10.9). Bacteria belonging to the phylum Chloroflexi were relevant in autumn, Spirochaetota, Verrucomicrobiota, Fusobacteriota, and Cyanobacteria were particularly abundant in winter while Bacteroidota characterized summer fish. A total of 332 prokaryotic families were identified with 26 most abundant ones; Rhodociclaceae (Proteobacteria) were dominant in autumn, Brevinemataceae (Spirocheaetota) and Fusobacteriaceae (Fusobacteriota) were especially present in winter and the Staphylococcaceae (Firmicutes) prevailed in spring. Conclusion: This study sheds light on the variation in the complex gut microbial community structure of Mediterranean grey mullets and their potential ecological role in protecting fish and preserving the aquatic environment.

Evaluation of different methods for reference evapotranspiration assessment: A case study for Ukraine

The paper presents the results of the study devoted to the examination of the accuracy and reliability of the temperature-based approach of the ‘Evapotranspiration Calculator (Ukraine)’ application for the reference evapotranspiration assessment in Ukraine. The objective of the study was to determine the level of reliability and accuracy of modern alternative temperature-based algorithms for the reference evapotranspiration assessment in Ukraine compared to internationally recognized methods. The study was carried out for the territories of Ukraine, based on the meteorological data for the period 2021–2023. The basic methodology was compared to the standard Penman-Monteith method and the method of Hargreaves. The comparison was performed using the values of MAPE, RMSE, and correlation coefficient. Statistical analysis testified that there is a strong correlation and subtle difference between the Hargreaves method and the ‘Evapotranspiration Calculator (Ukraine)’ application, with an average MAPE of 30.3%, the correlation coefficient of 0.92, and RMSE of 1.46 mm. The difference between the Penman-Monteith method and the studied methodology was greater, as the MAPE averaged 41.0%, the correlation coefficient was 0.87, and the RMSE value was 2.05 mm. However, the high variation of the results by the regions of the country and the years of the study did not allow us to draw solid conclusions on whether the methodology embedded in the ‘Evapotranspiration Calculator (Ukraine)’ application is inferior to the method of Penman-Monteith. Further studies are required to clarify this issue through the improvement in the dataset, involvement of in-field reference evapotranspiration measurements, and application of adjustment guidelines for the ‘Evapotranspiration Calculator (Ukraine)’ application.

A Species Complex in the Iconic Frog-Eating Bat Trachops cirrhosus (Chiroptera, Phyllostomidae) with High Variation in the Heart of the Neotropics

A Species Complex in the Iconic Frog-Eating Bat Trachops cirrhosus (Chiroptera, Phyllostomidae) with High Variation in the Heart of the Neotropics

Effect of bicultural rearing of pikeperch (Sander lucioperca) and Russian sturgeon (Acipenser gueldenstaedtii) on growth and fish condition parameters in RAS

This study investigated the intensive rearing of pikeperch (Sander lucioperca) and Russian sturgeon (Acipenser gueldenstaedtii) in a recirculating aquaculture system for 84 days, with five different stocking ratios (with P as a percentage of pikeperch): P100, P90, P80, P70, and P0. The growth parameters, fish condition parameters, and blood biochemistry were measured. The P70 group showed the highest final total length, standard length, and body weight of pikeperch (82.95 ± 18.92 g), while the lowest values were found in Groups P100 (63.46 ± 18.49 g) and P90 (68.63 ± 13.79 g). The sturgeon did not show significant differences, except for Group P90, which had the lowest body weight (86.10 ± 33.95 g). Survival rates were high for pikeperch (96.098.6%) and no mortality in the sturgeon was evident in all groups. The feed conversion ratio (FCR) for pikeperch was similar between Group P100 (0.88 ± 0.02) and the two bicultural groups P90 (0.80 ± 0.04) and P80 (0.69 ± 0.05). For the sturgeon in Group P0, had a comparable FCR (0.71 ± 0.13). The lowest FCR for sturgeon was observed in the bicultural group P70 (0.66 ± 0.03). Tissue-somatic indices, hepatosomatic index (HSI), and fat-somatic index (FSI), supported significant differences only for pikeperch, with the highest values for the P80 and P70 groups. This study of pikeperch and Russian sturgeon rearing in various stocking ratios for 84 days demonstrates optimal growth and health parameters in the P70 group for pikeperch, with overall high survival rates and minimal health variations in sturgeon, suggesting the effectiveness of a mixed species approach in recirculating aquaculture systems.

Severe wildfire increased variability in the response of gross primary production to climate in an Eucalyptus dominated semi-arid woodland in South Australia

Frequency and severity of wildfires have intensified in many regions in the world. High severity fires often initiate vegetation regrowth and succession, and thus alter ecosystem processes and functioning. Understanding how high severity fire-induced variations in gross primary production (GPP) respond to climate variability is critically important. This study aimed to quantify fire-induced changes in the response of GPP to concurrent and antecedent precipitation and air temperature in a semi-arid woodland in South Australia, using MODIS derived near-infrared reflectance of vegetation (NIRv) time series data (2000–2021) and associated climate data. Additionally, the magnitude and time course of climate legacies on GPP of unburnt and severely burnt sites were determined. The results showed that fire severity increased the variability in post-fire vegetation recovery. Prior to fire disturbance, NIRv as a proxy of GPP, was predominately affected by both concurrent and antecedent precipitation. Pre-fire precipitation legacy was about 9 months. Post-fire precipitation legacy duration was shorter in the unburnt patches within fire scar (ca. 9 months) than outside the fire scar (ca. 15 months), suggesting that the unburnt patches remaining within fire scar were more vulnerable to climate change than the adjacent intact woodland. In addition, the temperature legacies varied over time, likely mediated by water availability in this woodland. Post-fire regrowth from lignotubers was not significantly affected by concurrent and antecedent climate variables, but dependent upon endogenous growth which depends on previous growth conditions. This may be due to the smaller root system which reduced the capacity for taking up rain water after the fire event when annual precipitation was relatively low. We suggest that higher temperature together with reduced and more variable precipitation in the future could induce greater uncertainty in recovery of Eucalyptus trees post-fire.

Hide and seek: chemical cues drive site preference among potential mates and intraguild competitors

Abstract Chemical perception is essential among arthropods for mate recognition, prey search, and predator avoidance, especially for solitary predators which are often aggressive. Such mechanisms may be intensified in environments like the Caatinga, a seasonally dry tropical forest in Brazil, characterized by low habitat complexity and high seasonal variation. Thus, we investigated chemical perception between two scorpion species from this environment, involved in intraguild competition. Experiments assessed their response to chemical cues from prey, predators, and potential mates. We use Y-mazes to test the time spent by the scorpions between Y-arms with or without a given substrate-borne chemical cue (site preference) and the number of active individuals during trials (presence of activity). Scorpions’ activity was not influenced by chemical stimuli, although they clearly exhibit site preferences. The smaller predators avoided sites with the larger species’ chemical cues, while the larger predators preferred sites with the smaller species’ cues. Additionally, both species trailed female chemical cues. These findings suggest a dual-oriented arms race where prey and predator modulate their behaviour to avoid and hunt heterospecifics, respectively. This study provides the first evidence of a scorpion using chemical cues to detect a heterospecific scorpion and highlights the importance of this trait in arachnids.

Cascading blackout severity prediction with statistically-augmented graph neural networks

Higher variability in grid conditions, resulting from growing renewable penetration and increased incidence of extreme weather events, has increased the difficulty of screening for scenarios that may lead to catastrophic cascading failures. Traditional power-flow-based tools for assessing cascading blackout risk are too slow to properly explore the space of possible failures and load/generation patterns. We add to the growing literature of faster graph-neural-network (GNN)-based techniques, developing two novel techniques for the estimation of blackout magnitude from initial grid conditions. First we propose several methods for employing an initial classification step to filter out safe ‘non-blackout’ scenarios prior to magnitude estimation. Second, using insights from the statistical properties of cascading blackouts, we propose a method for facilitating non-local message-passing in our GNN models. We validate these two approaches on a large simulated dataset, and show the potential of both to increase blackout size estimation performance.

Modelling changes in whole body and fillet fatty acid composition of Atlantic salmon with changing levels of dietary omega-3 intake

In this study, a fatty acid dilution model was coupled with a dynamic nutrient demand model to provide an integrated model capable of predicting the whole-body and fillet lipid and fatty acid levels of Atlantic salmon (Salmo salar) following a change in dietary fatty acid profile. Based on knowledge of the initial fish and dietary fatty acid compositions, diet digestible energy density, the water temperature and duration of feeding, the model demonstrated that it was possible to predict a range of parameters, including the growth, feed utilisation, whole-body and fillet (Norwegian Quality Cut; NQC) total lipid, and fatty acid levels of the fish. The model was validated against five separate experiments, including two farm-based trials with harvest size fish. Validation experiments involved fish ranging in size (initial weights to final weights) from 138 g/fish to 5138 g/fish and running for durations of between 66 and 323 days. For the laboratory experiments, prediction of growth, feed utilisation and fatty acid deposition proved to be highly predictable (R2 > 0.998). Fatty acid profiles from both short and long-term cage trials were also highly predictable. Despite the reduced level of weight change in the short-term cage trial, and the higher variability that was observed in growth performance, the fatty acid deposition still showed high levels of correlation (R2 > 0.996), between the modelled and measured fatty acid levels in the fish fillet. Departure from linearity was more evident in the long-term cage trial, but correlation still exceeded R2 > 0.995 for all treatments. Prediction of whole-body and NQC total lipid levels was less accurate, with correlations being R2 = 0.962 and R2 = 0.909 respectively. Model outputs were generally more accurate with greater weight change and/or experiment duration. The outcome of this study shows that the model developed here provides a useful tool for the estimation of the fatty acid composition of Atlantic salmon following a change in dietary fatty acid composition. This could help assist in the more judicious use of dietary long-chain omega-3 fatty acids for commercial salmon farming.

A Photographic Approach Studying the Orientation of the occlusal plane of the Malaysian Population. A Proposal for an Orienting Device

The occlusal plane is crucial in prosthodontic reconstructive treatment as it affects the most important factors for the proper functioning of the artificial prostheses. The achievement of correct occlusal plane position offers maximum aesthetic, phonetic, mastication, and patient’s satisfaction. An incorrectly oriented occlusal plane interferes with denture stability and retention, in addition to more vital functions of the teeth and oral cavity. This study used a photographic approach to determine the occlusal plane inclination in relation to some anatomical references. 95 young volunteers of Mahsa University College, aged between 20 and 25 years, were selected for this study. The participants were selected according to specific inclusion criteria. A standardized digital profile and front images were taken for each participant using a digital camera that is fixed on a tripod with the fox bite plane placed on the occlusal surfaces of the maxillary teeth. The angle amplitude of the reference planes in relation to the occlusal plane was measured using a digital protractor on the screen display. The results revealed that the least mean angle difference was with the AT1, while higher variability was found using the Frankfort plane. In addition, there were no significant differences between the two genders or among the three ethnic groups. It is concluded that the photographic method can be used successfully to study the occlusal plane, and the lowest point of the tragus is the best posterior reference point to determine the ideal location of the occlusal plane.

An approach to brand planning under high competitor set variation

We present a novel approach to enable parsimonious local brand planning in situations where a brand’s competitive set varies substantially across points of sale. We conceptualize the entire assortment of products from all the rivals at a point of sale as a unique, holistic unit of competition that vies with the focal brand for a share of the local market. We then apply a mixture-type model to consumer transactions data to explicate clusters of assortments within which a brand has similar levels of sensitivity to assortment composition and local marketing mix activities. Our results reveal substantial variation in these assortment clusters across brands within a product category. Additionally, we find large variation in the sensitivity of a brand’s share to local marketing instruments, and asymmetry in the effectiveness of these instruments in offensive versus defensive modes. We use these findings to provide guidance for parsimonious local marketing planning in situations where competitive assortments vary across points of sale.

Combining AMMI and BLUP analysis to select high‐yielding soybean genotypes in Benin

AbstractThirty soybean [Glycine max (L.) Merr.] genotypes, along with three checks, were evaluated over three seasons across five communes in Benin. The experiments were laid out in an alpha lattice design with three replicates. Additive multiplicative mean interaction (AMMI) and best linear unbiased predictor (BLUP) analysis were combined to assess differential agronomic performance and yield stability among genotypes. There was significant variation (p < 0.001) between genotypes for all traits, with highly significant environmental and genotype × environment interaction (GEI) effects on soybean grain yield (p < 0.001). The likelihood ratio test indicated that both genotype and interaction effects were highly significant (p < 0.001). The low R2 (0.21) for GEI reflected the presence of high residual variation in the GEI component, in contrast to the AMMI analysis of variance, which explained a high proportion of the GEI through the first two interaction principal component axes (52%). The very high value of the predictive accuracy (0.89) confirmed the model's reliability in selecting superior genotypes. The low (0.33) genotypic correlation between environments indicated that it was difficult to select superior genotypes for each environment. Based on the superiority index (weighted average absolute scores from BLUP for yield) of BLUP, simultaneous selection led to the identification of Jenguma 2.67 ± 0.06 t ha−1 as the most stable and productive genotype across environments, followed by Favour 2.34 ± 0.08 t ha−1, and Afayak 2.46 ± 0.08 t ha−1. The agronomic performance of soybean in this study suggested great potential for diversifying cotton‐based cropping systems in Benin, thereby improving their sustainability. The effect of these soybean genotypes on the productivity of intercrop combinations and sequences of cash crops, such as cotton, is yet to be investigated.

Relationship between BRAF V600E and some aggressive features in papillary thyroid carcinoma ≤1.5 cm

Objectives: Determine the association between BRAF V600E mutation in papillary thyroid microcarcinoma (PTMC), small papillary thyroid carcinoma (PTC 1-1.5 cm), with tumour-aggressive characteristics. Subjects and methods: Retrospective descriptive study of 104 patients with PTMC diagnosed by histopathology and with BRAF V600E gene mutation testing results. Study subjects were divided into 2 groups: PTMC (tumour size ≤1.0 cm) and PTC 1-1.5 cm (tumour size 1-1.5 cm) and evaluated aggressive features (macroscopic extrathyroidal invasion, lymph node metastasis, high-risk variants). Results: BRAF V600E gene mutation was detected in 72.8% of PTMC and 76.5% of PTC 1-1.5 cm. The proportion of tumours with aggressive features in PTMC with and without mutations was 66.7 and 52.63%, respectively (p=0.28). The proportion of tumours with aggressive features in PTC 1-1.5 cm with and without mutations was 80.7 and 100%, respectively (p=0.309). In the PTMC group, the rate of extrathyroidal invasion was higher in tumours with BRAF V600E mutation (p<0.05). No association was found between BRAF V600E gene mutation and lymph node metastasis, high cell variation, and more than one aggressive feature in both PTMC and PTC 1-1.5 cm patient groups. Conclusions: In the PTMC group, the rate of extrathyroidal invasion was higher in patients with the BRAFV600E mutation. No association was found between BRAFV600E gene mutation and other aggressive features in patients with PTMC and PTC 1-1.5 cm.

Leaf Anatomy Structure of Codiaeum variegatum (L.) Rumph. ex A. Juss Cultivars

Codiaeum variegatum (L.) Rumph. ex a. Juss is a common ornamental plant with a high variation of leaves shape and colour. This study aimed to analyze the leaves’ anatomy and the phenetic relationship between eight cultivars of C. variegatum which were defined by the differences in leaf morphology. The paraffin method prepared the transversal section of leaves, and anatomical characters were converted into binary data to calculate the similarity coefficient which was analyzed by Numerical Taxonomy System (NTSYS) 2.1 version. Leaves of eight cultivars of C. variegatum are varied in the anatomical structure of the primary vein and lamina. The eight cultivars of C. variegatum were clustered into four. The variations were found in 19 primary vein and lamina anatomy characteristics and the similarity coefficient is up to 0.59 between all cultivars. It can be concluded that the combination of leaf anatomical structures and midrib anatomical characters have notable taxonomic implications for future research.

Indirect non-linear effects of landscape patterns on vegetation growth in Kunming City

Urban greening is becoming an important strategy in improving urban ecosystem services and sustainability. Identifying the response of vegetation to urbanization and urban landscape patterns can help in planning for urban greening. Urbanization may lead to both direct and indirect effects on vegetation, and the indirect effects of urbanization on vegetation growth (UIE-VG) have been paid much attention recently in large scale. In this study, we investigated the spatiotemporal evolution of UIE-VG and the effects of landscape patterns on UIE-VG using the boosted regression tree model and remotely sensed data. An increase in average UIE-VG from 4 to 56% was found during urbanization of Kunming, the case study area in southwest China. However, UIE-VG exhibited high variations due to landscape pattern changes at the local scale. Overall, area-related and aggregation-related landscape metrics had greater effects on UIE-VG than the other metrics. The increase and aggregation of built-up land enhanced UIE-VG by 3.1–81.3% while the increase and aggregation of unused land and waterbodies reduced UIE-VG by 0.7–20.6%. Moreover, we found that the large and aggregated vegetation areas may mitigate the negative UIE-VG in low urbanization areas. Our findings have important implications for integrating urban landscape planning into sustainable urban greening strategies.