Phenological Studies Research Articles

Mapping and evaluating plant phenology in the Qinghai-Tibet Plateau: A digital approach using the plant Phenological Index (PI)

A new plant Phenological Index (PI) has been developed based on the visibility of plants, communities, and ecosystems. An evaluation and assessment of Zhang's Phenological Index (PI) were further examined based on the field observations of Alpine Shrub and Alpine Meadow vegetation at Haibei Alpine Ecosystem Research Station in the Northwest Qinghai-Tibetan Plateau.Zhang's PI is a measure of the plant's phenological status on the time intervals, calculating the accumulation of PI area in two dimensions. Two phenological variables were described as the Phenological Average Ratio (PAR) and the Lasted Days (LD). The LD may overlap when a certain percentage of the plant population has a nutritional stage that lasts longer than one additional phenological stage or occurs between two phenological stages. Correspondingly, the standard deviations of the observed multiple plant species represent plant population variations. After reviewing the PI applications for phenology studies on Alpine Shrub and Alpine Meadow vegetation, we found that they provide a means of measuring and comparing plant phenology at various levels - population, community, and ecosystem.During the start and end of the season in the Alpine Plateau region, plant phenological changes were significantly constrained by the environmental factors. However, during the summer season, Sunlight Hours (X4), Accumulated Ground Temperature (X3) and Accumulated Air Temperate (X1) above 0 °C had a more uniform impact on plant phenology across the region.Zhang's PI can be used for climate change research by altering warming temperatures, water conditions, and nutrient levels. We also discussed the concern of applying Zhang's PI to global warming research. Moreover, the Seasonal Phenological Index (SPI) can be described on a regional scale and used with ASOS, AEOS, SPAR, and SLD characters to evaluate the changes in the timing of seasonal events in Eqs. (3)(4)(5).

An Integrative Review of Drivers and Responses of Grassland Phenology under Global Change

This review synthesizes studies of grassland phenology and associations with plant resource-investment tradeoffs, functional traits, environmental and genetic regulators, genome size (GS), and management practices of nitrogen (N) fertilization, grazing, and mowing. Afterwards, the following five knowledge gaps were identified: (i) there is a lack of clarity of constraints of resource acquisition and allocation strategies, which constitute the plant economics spectrum, on herbaceous species vegetative and reproductive phenology; (ii) evidence is lacking for the tuning of phenology by functional traits via coordination of niche dimensionality and nutrient complementarity in species with contrasting community dominance; (iii) the role of keystone regulatory genes, such as AIL1, FDL1, ABI3, FT, and FRIGIDA, on phenology under contrasting environmental conditions (temperature, water, photoperiod) require confirmation; (iv) there is an urgent need to quantify trait-based and resource-partitioning links between GS and phenology to improve understanding of species coexistence; and (v) effects of N fertilization, grazing and mowing on phenological stages of coexisting species and growing season length, through impacts on inter-specific functional traits, light competition, pollination-syndromes, and carbon-investment economics are unclear. Thus, this review has identified areas of research that need to improve model predictions of the direction and magnitude of plant community responses and evolutionary mechanisms under global environmental change.

The Dormancy Types and Germination Characteristics of the Seeds of Berberis koreana Palibin, an Endemic Species of Korea

Berberis koreana Palibin is an endemic plant native to Korea. In this study, we aimed to study the seed germination of this species using a water imbibition experiment, gibberellic acid (GA3) treatment (0, 10, 100, or 1000 mg·L−1), cold stratification (0, 2, 4, 8, or 12 weeks at 4 °C), move-along experiment, and phenology studies. In the water imbibition experiment, the weight of the seeds increased by more than 120% in 24 h. An analysis of the internal and external morphological characteristics of the seed revealed that the embryo was already fully grown from the fruit and did not grow thereafter. The final germination percentages for the cold stratification at 0, 2, 4, 8, and 12 weeks at 4 °C were 12 ± 3.65, 32 ± 9.09, 59 ± 1.00, 59 ± 9.59, and 71 ± 1.91%, respectively. In the move-along experiment and phenology studies, a longer low-temperature treatment period resulted in a higher germination percentage. However, the GA3 treatment had little effect on the seed germination. Our results indicate that B. koreana exhibits an intermediate physiological seed dormancy.

Study on the Phenology of Three Fruit Trees Species in Purwodadi Botanical Gardens, East Java, and Its Relationship with Mesoclimates

Nowadays the study of phenology has taken an important contribution to climate change research. Therefore this study observed local fruit trees species collected in the Purwodadi Botanical Gardens (PBG); they were Flacourtia rukam (Zoll & Moritzi), Limonia acidissima L., and Manilkara kauki (L) Dubard. We used fruit phenology data from 2014 to 2018 as secondary data to describe the changes. We also observed the weekly phenology of flowering and fruiting for three years from 2019 to 2022. At the same time, mesoclimates components included precipitation, maximum and minimum temperature were daily recorded by the PBG weather station measurement. Data pairs were then analyzed by using a structural modeling of WarpPLS to determine the relationship among mesoclimates and phenology variables. Research showed that phenology of flowering and fruiting of F. rukam, L. acidisissima, and M. kauki was significantly shifted from 2014 to 2022, along with changes in rainfall patterns, maximum and minimum temperatures in the PBG. Based on the Friedman test, it was shown that the maximum and minimum temperatures significantly changed (p<0.05). Five months of mesoclimates were significant predictors and affected before the measurement of phenological flowering and fruiting of three species. High precipitation significantly reduced maximum temperature, and increased minimum temperature. The high precipitation reduced the probability of flowering and fruiting initiation, except for those of L. acidissima. Increasing maximum temperature reduced flower and fruit set of F. rukam and L. acidisissima, while it reduced flowering of L. acidissima. Furthermore, minimum temperature induced flowering, except in L. acidissima.

Experimental designs for testing the interactive effects of temperature and light in ecology: The problem of periodicity

AbstractTemperature and light cues interact to control many biological processes. Experiments give researchers the ability to manipulate these environmental cues independently and can be designed to robustly quantify their individual and interactive effects on any particular biological activity. Such experiments have produced important insights into the environmental controls on numerous biological processes in both plant and animal taxa across terrestrial and aquatic environments. Testing the interactive effects of multiple environmental cues, however, requires experimental treatments to be fully independent; any unmeasured experimental covariation among treatments can result in incorrect conclusions.Using a database of controlled environment experiments on the spring phenology of woody plants as a case study, we highlight how a common experimental set‐up, designed to parse the interactive effects of temperature and photoperiod on time to budburst, introduces a latent experimental covariation of these treatments by coupling photo‐ and thermoperiodicity. Using data simulations, algebraic corrections and a comparative analysis of published experiments, we demonstrate how this unmeasured experimental covariation biases statistical inference regarding the relative contribution of light and temperature cues to phenological variation.We identify this experimental covariation in more than 40% of published phenology studies that manipulate photoperiod. Our analyses demonstrate that the coupling of thermo‐ and photoperiodicity results in the overestimation of the effect of photoperiod, the underestimation of forcing effects, and misleading conclusions about their interactions on phenology. This may, in part, explain why the significance of photoperiod cues for spring phenology is currently debated in the literature.Accurate forecasting of how varying environmental conditions will impact the dynamics of biological events requires accurately quantifying cue responses. To this end, we present several options for statistical corrections and alternative experimental designs that can provide more robust estimates of the relative effects of temperature and photoperiod on phenology and many other biological processes controlled by temperature and light.Read the freePlain Language Summaryfor this article on the Journal blog.

Coding phenological growth stages of yellow bells (Tecoma stans (L.) Juss. ex Kunth) based on BBCH scale and its implications for urban greening

The precise knowledge of the seasonal influence on phenology, timing and duration of different growth stages (phenophases) exhibited in a life cycle of a plant is crucial for undertaking several crop management decisions. The reproductive growth stages hold a particular relevance in this regard that conveys a ‘seasonal shift’ and also a ‘shift’ in the timing, duration and intensity of vegetative and reproductive growth stages due to subnormal micro-climate induced by climate change. The present study investigates the phenological growth stages of Tecoma stans - a drought tolerant, yellow flowering shrub with a versatile use for urban greening and beautification. Till date, the phenological characteristics in T. stans have never been codified or described so far. The study was undertaken with an objective to codify the seasonal change in the phenological growth stages of T. stans using bi-numeric BBCH (Biologische Bun-desantalt, Bundessortenamt und Chemische Industrie) scale under subtropical climatic conditions of North West India. The experiment was planned on T. stans planted as a shrubbery block in a randomized block design layout. The distinct phenological growth stages of this shrub were represented through photographs. The year-round phenological calendar was also evolved exhibiting the time lapse of different phenophases along with their frequency and intensity of occurrence. Seasonal variation in mean temperature and precipitation markedly affected the phenological behavior of T. stans that exhibited seven major phenological growth stages namely, seed germination, leaf development, elongation of lateral shoots, inflorescence emergence, flower development, pod development and maturity of seed. The investigations undertaken are of vital interest to the urban landscape managers for the selection of species not only based on their aesthetic attributes but also to consider their functionality associated with the site-specific conditions. In addition, the salient findings will help deepen the understanding of weather-induced ‘eventful’ interactions of pollinators and flowers of T. stans that greatly benefit in a symbiotic manner, ensuring the survival and perpetuation of the species. The newly developed scale provides a unified standard for describing and identifying the phenological growth of T. stans that can potentially be utilized as a reference scale for undertaking future phenological studies.

Weedy rice (Oryza sativa L.) seed dormancy features and potential usage for management

Weedy rice infestation has been expanding with the increasing proportion of direct-seeded rice (DSR) systems in China. Limited herbicides are effective against weedy rice due to its high similarity with cultivated rice. Hence, it is important to figure out some non-chemical management strategies for weedy rice. One of the methods is to reduce the size of seed bank by inducing weedy rice germination. Petri dish germination experiment found that weedy rice with different seed morphologies showed an absence of primary dormancy. The field phenology study showed that weedy rice differed from cultivated rice in many features including plant height, number of tillers, fresh weight, and days required for earing when sown from 1 June to 1 October, and in the case of late sowings (between 1 August and 1 October), the plants produced no heads despite a high germination rate. Simulated field experiment to induce germination found that when soil moisture content was 22.2% and day/night temperatures were 20/15 °C, respectively, germination was more than 60% up to 10 days after sowing; at higher levels of soil moisture and temperature, germination was faster and germination percentage was higher. These results indicated that weedy rice seed bank size could be reduced by inducing the seed germination with post harvest irrigation as the seedlings would be killed overwinter in lower-middle reaches of the Yangtze River in China.

Study of Flowering Phenology of West Sumatera Local Jamblang (Syzygium cumini (L.) Skeels)

The flower of the jamblang plant (Syzygium cumini (L.) Skeels) is a type of compound flower. The jamblang flowers have a panicle like shape with branches that are far apart. The phenology study has practical importance for planning the plant breeding program, including if there will be the development of superior jamblang varieties. The purpose of this study was to determine the development and biological characteristics of jamblang flowers. The observation was conducted on the duration of the flower initiation phase, the small bud phase, the large bud phase, and the complete blooming phase (anthesis), and also flower biological characteristics. This research was carried out in Padang City from February to May 2022 using a survey method with purposive sampling. There are three of plant genotypes that were used as object in this study. The development of jamblang flowers in each phase has a different time for each flower genotype. The characteristics of flowers have similarities in each of their genotypes. Jamblang plant is classified as plants that have a complete flower structure and a perfect flower because it has two penitals on one flower.

PHENOLOGICAL RESPONSE OF SOME SPECIES OF THE FAMILY RANUNCULACEAE TO CLIMATE CHANGE IN CENTRAL YAKUTIA

The study of plant phenology is an important point in a changing climate. The purpose of these studies is to analyze regional climate changes in Central Yakutia and the phenological response of 4 species ( Pulsatilla angustifolia , Adonis sibirica , Delphinium grandifloru m и Aconitum barbatum ) of wild herbaceous plants to these events over the past 60 years. A statistically significant positive trend was observed in the temperature regime of Yakutsk for 1961-2021. The average air temperature of the frost-free period increased by 1,4 ºС, the growing season by 0,9 ºС and the summer season by 1,2 ºС. The average yearly precipitation has not changed significantly during this period. The increase in air temperature has led to minor shifts in the seasonal development of plants, which vary in duration and orientation. The earlier onset of the terms of the phenological phases is noted at the beginning of the growing season, and a significant shift is noted only in the terms of the spring regrowth of A. sibirica (p = 0,0314). The shift of the dates of the end of vegetation to later dates was noted in three species. The end of the vegetation of the short-vegetating hemiephemeroid A. sibirica has shifted to earlier dates. There were no significant differences in the duration of the prefloral period, which is due, to a greater extent, to the biological characteristics of the species rather than environmental factors. Changes in vegetation duration are more noticeable, although p-values are higher than the significance level (p = 0,1-0,8). There was a significant increase in the duration of vegetation only in A. barbatum (p = 0,04). This slight shift in the dates of the onset of the main phenological phases shows the inertia of the phenological response of plants to regional climate changes.

Flowering biology and fruiting phenology study in white cross-berry (Grewia tenax (Forssk.)) Fiori.

Current emphasis on food supply, market value, and therapeutic use of underutilised crops makes Grewia tenax suitable for commercial production. Therefore, flowering biology and fruiting phenology study were carried out on field-established G. tenax plants in Kachchh, Gujarat, from February - March 2018. Flowers are scented and cream-white with yellow stamens and composed of 5 petals and sepals, an ovary and a style, 2 anther lobes and many anthers (66.33 ± 7.51). Bud initiation started in the last week of February and anthesis was observed after 6.40 ± 0.18 days of bud initiation. Flower anthesis start at 1130 h and is completed at 1330 h, with peak anthesis during 1215-1230 h in February. On an average, 15.55±0.98 and 19.55±0.98 days are required for fruit maturity and ripening. The study revealed that the fruit traits of the white cross berries, including fruit length and diameter, varied within the ranges of 4.93-6.69 mm and 4.06-5.91 mm, respectively. As there is limited information available on this species, these findings provide a foundation for further genetic research on white cross berries. This study can serve as a valuable resource for future investigations aiming to enhance our understanding of the genetic makeup of this species and potentially improve its fruit traits through breeding programs.

Practice makes the expert: The importance of training volunteers in the generation of phenological data from photographs of biodiversity observation platforms.

Phenology studies the time at which events in the life cycle of a species occur sand how they are related to environmental cues. Patterns of change in phenology at different scales can be used as an indicator of ecosystem changes and climate change, but the data necessary to detect these changes can be difficult to obtain due to their temporal and regional dimensions. Citizen science can contribute to generate large amounts of data on phenological changes at wide geographical scales that would be almost impossible for professional scientists to generate, but the quality and reliability of these data are often questioned. The objective of this study was to evaluate the use of a biodiversity observation citizen science platform based on photographic information as a potential source of large-scale phenological information, and to identify the key benefits and limitations of this type of information source. We used the Naturalista photographic databases for two invasive species in a tropical region: Leonotis nepetifolia and Nicotiana glauca. The photographs were classified into different phenophases (initial growth, immature flower, mature flower, dry fruit) by three groups of volunteers: a group of experts, a trained group with information on the biology and phenology of both species, and an untrained group. The degree of reliability of the phenological classifications was estimated for each group of volunteers and each phenophase. The degree of reliability of the phenological classification of the untrained group was generally very low for all phenophases. The group of trained volunteers showed accuracy levels for the reproductive phenophases that equaled the degree of reliability among the expert group, regardless of species, and was consistent across phenophases. We conclude that volunteer classification of photographic information contained in biodiversity observation platforms can provide phenological information with high geographic coverage and an increasing temporal coverage on general phenological patterns of species with wide distributions but has limited applicability in the identification of exact start and end dates. and peaks of the different phenophases.

A century of climate warming results in growing season extension: Delayed autumn leaf phenology in north central North America.

Shifts in the timing of key leaf phenological events including budburst, foliage coloration, and leaf fall have been observed worldwide and are consistent with climate warming. Quantifying changes in growing season length (GSL) because of shifts in both spring and autumn leaf phenology is crucial for modeling annual net ecosystem carbon uptake. However, a lack of long-term autumn phenology datasets has prevented assessment of these growing season level changes. We investigated shifts in growing season length, budburst, foliage coloration, and leaf fall over the past century in seven native hardwood species using a historic leaf phenology dataset collected in Wauseon, OH from 1883-1912 paired with contemporary observations. Using long-term meteorological data, we investigated temperature and precipitation trends over 130 years. Finally, we correlated spring and fall phenophases with monthly temperature and precipitation variables from the twelve months preceding that phenophase using historical meteorological data. We found significant extension of growing season length over the past century in five of the seven study species (ANOVA, p < 0.05) which resulted primarily from delayed foliage coloration rather than from earlier budburst in contrast to the few other studies assessing total GSL change. Our results suggest that most of the leaf phenological studies that investigate only budburst are disregarding crucial information about the end of the growing season that is essential for accurately predicting the effects of climate change in mixed-species temperate deciduous forests.

Spatial-temporal variations of forest and grassland phenology in the Yellow River Basin during 2000-2018.

The study of vegetation phenology is of great significance for understanding global climate change. The Yellow River basin has a wide spatial range and a complex ecological environment. The phenological characteristics of forest and grassland need further clarification. Based on the MODIS-EVI data from 2000 to 2018, we extracted the phenology of forest and grassland in the Yellow River basin using piecewise logistic and double logistic phenological models with the corresponding curvature change extremum method and derivative method, respectively. The temporal and spatial variations of phenological parameters were analyzed. The start of growing season (SOS) was at 90-165 day of year (DOY), and gradually delayed from southeast to northwest. The increase of 100 m elevation delayed SOS 0.94 d, and the SOS of forest was earlier than that of grassland. The end of growing season (EOS) was at 270-315 DOY, which delayed from west to southeast. For every 100 m increase in altitude, the EOS advanced 0.63 d, with EOS of forest being later than that of grassland. The length of growing season (LOS) was 110-230 d, which shortened gradually from southeast to northwest. The LOS of forest was larger than that of grassland. During the study, SOS showed an advance trend from 2000 to 2018 with a rate of 4.1 d·(10 a)-1, and the proportion of spatial advance area was 73.2%. There was an obvious advance in the central part of the basin. EOS generally showed a significant postponement trend with a rate of 2.3 d·(10 a)-1, and the proportion of spatially delayed area was 63.4%, the phenological advance and delay of forest was less stronger than that of grassland. LOS showed a significant prolongation trend with a rate of 6.4 d·(10 a)-1, and the proportion of spatial extension was 71.8%. The piecewise Logistic and double Logistic phenological models and the corresponding curvature extremum method and derivative method were suitable for the extraction of natural vegetation in the Yellow River Basin. The overall LOS of forest and grassland showed a prolonging trend, which was shortened with the increases of altitude. The LOS of forest was longer than that of grassland in the study area.

The Entangled Phenology of the Olive Tree: A Compiled Ecological Calendar of Olea Europaea L. Over the Last Three Millennia With Sicily as a Case Study.

Seasonal cycles in plants and animals drive key timings of human practices in an agrosystem like the best time for harvest, planting, or pruning. Within the framework of historical phenological studies, we attempt a reconstruction of the olive (Olea europaea L.) phenology along millennia. Thanks to its extraordinary longevity, the olive tree is a living proxy from the past and embodies a still uncollected long-term memory of ecological behaviors. A cultural keystone species, olive cultivation has more and more played a crucial role for biodiversity conservation, livelihood of rural communities and their enrooted cultural identity in the whole Mediterranean. By compiling traditional phenological knowledge from historical written sources and oral traditions, and using it as historical bio-indicator of the linkage between human ecological practices and seasonal changes of plant behavior, we compiled a monthly ecological calendar of the olive tree covering the last ∼2800years. As a case study, we chose a special place: Sicily, unique for its position in the Mediterranean, geomorphology and legacies in the form of cross-temporal accumulated eco-cultures. Such a sui generis ecological calendar provides an additional case study to explore the intertwining of plant behavior and human adaptation strategies and the interplay between cultural diversity, ecological disturbance and phenological stability. All of this, in turn, can inform action for the present and future sustainable management of these millennial trees.

Study on Phenology of Some Papilionoid Taxa (Papilionoideae- Leguminosae)

Phenology emphasizes the significant timing of biological events occurring in an annual cycle of the plant and explains seasonal aspects of an ecological phenomenon. The current work describes the phenological studies of Papilionoideae taxa in Hosadurga and Holalkere taluks of Chitradurga districts (Karnataka, India). Different phenophases like leafing, flowering, fruiting, and leaf fall were observed for 52 species that belong to 34 genera of Papilionoideae taxa. Investigation of important phenophases clearly showed the peak period of different phenophases and helped to understand how it differs from region to region and also with environmental changes and economic concerns of that area. The obtained database can be utilized for further conservation and biodiversity maintenance in that region.

Chromosome-Level Assembly of Flowering Cherry (Prunus campanulata) Provides Insight into Anthocyanin Accumulation.

The flowering cherries (genus Prunus, subgenus Cerasus) are popular ornamental trees in China, Japan, Korea, and elsewhere. Prunus campanulata Maxim. is an important species of flowering cherry native to Southern China, which is also distributed in Taiwan, the Ryukyu Islands of Japan, and Vietnam. It produces bell-shaped flowers with colors ranging from bright pink to crimson during the Chinese Spring Festival from January to March each year. We selected the P. campanulata cultivar "Lianmeiren", with only 0.54% of heterozygosity, as the focus of this study, and generated a high-quality chromosome-scale genome assembly of P. campanulata by combining Pacific Biosciences (PacBio) single-molecule sequencing, 10× Genomics sequencing, and high-throughput chromosome conformation capture (Hi-C) technology. We first assembled a 300.48 Mb genome assembly with a contig N50 length of 2.02 Mb. In total, 28,319 protein-coding genes were predicted from the genome, 95.8% of which were functionally annotated. Phylogenetic analyses indicated that P. campanulata diverged from a common ancestor of cherry approximately 15.1 million years ago. Comparative genomic analyses showed that the expanded gene families were significantly involved in ribosome biogenesis, diterpenoid biosynthesis, flavonoid biosynthesis, and circadian rhythm. Furthermore, we identified 171 MYB genes from the P. campanulata genome. Based on the RNA-seq of five organs at three flowering stages, expression analyses revealed that the majority of the MYB genes exhibited tissue-specific expression patterns, and some genes were identified as being associated with anthocyanin accumulation. This reference sequence is an important resource for further studies of floral morphology and phenology, and comparative genomics of the subgenera Cerasus and Prunus.

Merged Multi-Sensor Ocean Colour Chlorophyll Product Evaluation for the British Columbia Coast

Phytoplankton phenology studies require a dataset that is continuous in time and space since missing data have been shown to affect the accuracy of seasonality metrics. The interpolated GlobColour product provided by the Copernicus Marine Environment Monitoring Service (CMEMS) meets these requirements by being ‘gap filled’, thus yielding the highest spatial coverage. Despite being validated on a global scale, a regional comparison to in situ Chl-a concentrations should be conducted to enable product application in optically complex waters. This study aims to evaluate the performance of the GlobColour interpolated product in British Columbia coastal waters via a statistical match-up analysis and a qualitative analysis to determine whether the data reflect the region’s large-scale seasonal trends and latitudinal dynamics. Additionally, the statistical performance of the GlobColour interpolated product was compared to the original GlobColour and Ocean Colour Climate Change Initiative (OC-CCI) merged chlorophyll-a products based on in situ observations. The GlobColour interpolated product performed relatively well and was comparable to the best-performing product for each water type (RMSE = 0.28, r2 = 0.77, MdAD = 1.5, BIAS = 0.90). The statistics for all the products degraded in Case 2 waters, thus highlighting the dilemma of applying algorithms designed for Case 1 waters in Case 2 waters. Our results indicate how the quality of products can vary in different environmental conditions.

Advances in influencing mechanism and model of total climatic production factors of plant phenology change

<p indent="0mm">Phenology is an important indicator of climate change. It is not only the key to vegetation dynamic simulation, but also directly affects the simulation accuracy of terrestrial carbon cycle and atmospheric general circulation model. This paper summarizes the research status of plant phenology from two aspects: phenological change mechanism and phenological simulation model, and analyzes the research trend of phenology. It points out that most of the current phenological studies only consider the impact of a single climate factor or a few climate factors, and there are still few studies involved in the interaction of multiple climate factors, let alone the interaction of total climate production factors determining plant phenology. Due to the limitation of the understanding of phenological change mechanism and the study of species, the existing phenological models cannot reflect the authenticity of vegetation growth, nor can they effectively simulate the phenological period. The paper points out that it is essential to study the relationship between phenology and total climatic production factors in order to comprehensively understand the mechanism of phenological change. Based on the fact that plant photosynthesis is the most important phenological influencing factor, this paper puts forward the viewpoint of using climate production potential as the driving factor of plant phenological change. Climate production potential not only reflects the comprehensive effect of climate and environmental factors on plant production and their consistency of these factors in the whole process of plant growth, but also includes the interaction between biological factors and environmental factors and the impact of extreme weather and climate events, which is able to realize the accurate simulation of phenology. The future phenological research directions proposed in this paper will help enrich phenological knowledge and improve the simulation accuracy of land carbon cycle model and atmospheric circulation model.

Effects of aspect on phenology of Larix gmelinii forest in Northeast China

The response of vegetation phenology to global climate change is one of the main forms in terrestrial ecosystem change, the study of vegetation phenology is an important complement to the understanding of how global climate change affects ecosystems in multiple dimensions. We selected the distribution area of Larix gmelinii in The Greater Khingan Mountains as a case area by eliminating the heterogeneity of vegetation types, with the support of Google Earth Engine platform, we studied the effects of different aspects and land surface temperature (LST) on remote sensing phenology (RSP) that is defined as start of growing season (SOS), end of growing season (EOS) and length of growing season (LOS) respectively in the study area through Normalized Difference Vegetation Index (NDVI) changes. The results showed that SOS advanced in different aspects during the study period, and the advance amplitude of SOS on the east and west aspect was greater than that on the south and north. Except for the east aspect, EOS showed a slight postponed, and LOS was prolonged on all aspects. The latitude difference between 51° and 53° N had no significant effect on L. gmelinii in different aspects. LST had an obviously direct effect on the RSP of L. gmelinii in different aspects, and the effect of LST on SOS and LOS was significantly greater than that on EOS. The effect of LST on SOS and LOS was significant in April and spring. The main contributor to the increase of LOS was the advance of SOS, while the postponed of EOS has a relatively small contribution to LOS. Due to the redistribution of meteorological factor by aspect, the spatial and temporal heterogeneity of RSP tends to be complex, so determining the same aspect is one of the main ways to reduce the phenological heterogeneity in the study of vegetation RSP.

Shoot Phenology in Bambusoideae: A Review

The study of plant phenology is important nowadays since global climate-changing phenomena are impacting the growing patterns and growing periods of plants. Bamboo is of great importance to the agriculture and forestry of temperate, subtropical to tropical regions, especially of Asia. Although some temperate genera can thrive under different climatic conditions, from the Korean Peninsula to South China, it is not known how bamboo will be affected by climate change, so the collection of data related to bamboo phenology could be of interest to research related to climate change. In this review, we describe available data on the phenology of 8 temperate genera, including 79 species, varieties and forms and 4 subtropical–tropical bamboo genera, including 19 species. Primarily, culm shoot physiology is discussed with some reference to leaf phenology data, where available, as well as their interaction. Since the data available in Western literature is often limited to the definition of season rather than exact dates and periods of given months, there is still a great need to explore more about the exact phenology of individual bamboo species to be able to determine the impact of periodic changes in weather patterns or climate change on bamboo phenology in the future.