Bloom Period Research Articles

Effects of typhoon events on coastal hydrology, nutrients, and algal bloom dynamics: Insights from continuous observation and machine learning in semi-enclosed Zhanjiang Bay, China

Typhoons can induce variations in hydrodynamic conditions and biogeochemical processes, potentially escalating the risk of algal bloom occurrences impacting coastal ecosystems. However, the impacts of typhoons on instantaneous changes and the mechanisms behind typhoon-induced algal blooms remain poorly understood. This study utilized high-frequency in situ observation and machine learning model to track the dynamic variations in meteorological, hydrological, physicochemical, and Chlorophyll-a (Chl-a) levels through the complete Typhoon Talim landing in Zhanjiang Bay (ZJB) in July 2023. The results showed that a delayed onset of algal bloom occurring 10 days after typhoon's arrival. Subsequently, as temperatures reached a suitable range, with an ample supply of nutrients and water stability, Chl-a peaked at 121.49 μg L−1 in algal bloom period. Additionally, water temperature and air temperature decreased by 1.61 °C and 2.8 °C during the typhoon, respectively. In addition, wind speed and flow speed increased by 1.34 and 0.015 m s−1 h−1 to peak values, respectively. Moreover, the slow decline of 8.2 % in salinity suggested a substantial freshwater input, leading to an increase in nutrients. For instance, the mean DIN and DIP were 2.2 and 8.5 times higher than those of the pre-typhoon period, resulting in a decrease in DIN/DIP (closer to16) and the alleviation of P limitation. Furthermore, pH and dissolved oxygen (DO) were both low during the typhoon period and then peaked at 8.93 and 19.05 mg L−1 during the algal bloom period, respectively, but subsequently decreased, remaining lower than those of the pre-typhoon period. A preliminary learning machine model was established to predict Chl-a and exhibited good accuracy, with R2 of 0.73. This study revealed the mechanisms of eutrophication status formation and algal blooms occurrence in the coastal waters, providing insights into the effects of typhoon events on tropical coastal biogeochemistry and ecology.

Documentation of Honeybees Flora and Blooming Period in Major Horticultural and Agricultural Crops Growing in Dryland Regions of Northern Karnataka, India

The goal of the present study was to determine the variety of nectariferous and polleniferous bee flora in the Koppal district of Northern Karnataka in order to enhance the bees' blooming season. When the blooming plants were visited, the honeybees' presence and foraging activity were documented. In a ten-minute interval when at least three honeybees visited the flowers, the plants were identified as bee foraging species. The various plant groupings that worker bees visit, including as fruit crops, vegetable cops, field crops, plantations, flower and ornamental plants, etc., are included in the identified bee flora. The detected flora was further divided into plants that yielded nectar, pollen, and both. A total of sixty-four crops were identified as forage crops. Of those, the Koppal district had plants that yielded nectar (14), pollen (13), and both (36), according to documentation. The major dearth times were discovered to be mid-April to mid-June, whereas the honey flow seasons were determined to be mid-December to mid-February and mid-July to mid-September. Based on the flora's availability, utility status, and duration of flowering, a floral calendar was established for the study area. The listed species (Syzygium, Cassia, Citrus, Pongamia, Azadirachta, Brassica, Areca, Cocos, Guizotia, Hilianthus, Albezia, Lagerstroemia, Polinathus, Sapindus, Tecoma) and others are some of the common and significant bee food plants.

Hit or miss? Impact of time series resolution on resolving phytoplankton dynamics at hourly, weekly, and satellite remote sensing frequencies

AbstractCharacterizing marine phytoplankton community variability is crucial to designing sampling strategies and interpreting time series. Satellite remote sensing, microscopy sampling, and flow through imaging systems have widely different resolutions: from weekly or monthly with microscopy sampling to daily when no cloud cover or glint is present with polar‐orbiting satellites, and hourly for autonomous imaging instruments. To improve our understanding of data robustness against sampling resolution at different taxonomic levels, we analyze 2 yr of data from an Imaging FlowCytobot with hourly resolution and resample it to daily, satellite‐temporal, and weekly microscopy sampling resolution. We show that weekly and satellite‐temporal resolutions are sufficient to resolve general community composition but that the randomness of satellite‐temporal resolution can result in overrepresenting or underrepresenting certain categories. While the yearly phytoplankton biomass bloom is detected in late winter by all four resolutions, category‐specific yearly blooms are generally consistent in timing but often underestimated or missed by the weekly and satellite‐temporal resolutions, introducing a bias in year‐to‐year comparisons. A minimum of biweekly sampling, particularly during known bloom periods, would lower the bias in such categories. Similarly, sampling time should be considered as daily variations are category‐specific. Overall, morning and low tide sampling tended to have higher biomass. We provide tables for categories detected by the IFCB in Narragansett Bay with their major bloom characteristics and recorded daily variability to inform future sampling designs. These results provide tools to interpret past and future time series, including possible detection of specific taxonomic groups with targeted satellite algorithms.

Re-oligotrophication and warming stabilize phytoplankton networks

Phytoplankton taxa are strongly interconnected as a network, which could show temporal dynamics and non-linear responses to changes in drivers at both seasonal and long-term scale. Using a high quality dataset of 20 Danish lakes (1989–2008), we applied extended Local Similarity Analysis to construct temporal network of phytoplankton communities for each lake, obtained sub-network for each sampling month, and then measured indices of network complexity and stability for each sub-network. We assessed how lake re-oligotrophication, climate warming and grazers influenced the temporal dynamics on network complexity and stability of phytoplankton community covering three aspects: seasonal trends, long-term trends and detrended variability. We found strong seasonality for the complexity and stability of phytoplankton network, an increasing trend for the average degree, modularity, nestedness, persistence and robustness, and a decreasing trend for connectance, negative:positive interactions and vulnerability. Our study revealed a cascading effect of lake re-oligotrophication, climate warming and zooplankton grazers on phytoplankton network stability through changes in network complexity characterizing diversity, interactions and topography. Network stability of phytoplankton increased with average degree, modularity, nestedness and decreased with connectance and negative:positive interactions. Oligotrophication and warming stabilized the phytoplankton network (enhanced robustness, persistence and decreased vulnerability) by enhancing its average degree, modularity, nestedness and by reducing its connectance, while zooplankton richness promoted stability of phytoplankton network through increases in average degree and decreases in negative interactions. Our results further indicate that the stabilization effects might lead to more closed, compartmentalized and nested interconnections especially in the deeper lakes, in the warmer seasons and during bloom periods. From a temporal dynamic network view, our findings highlight stabilization of the phytoplankton community as an adaptive response to lake re-oligotrophication, climate warming and grazers.

Structure and dynamics of plankton communities in the coastal zone of the Curonian Lagoon of the Baltic Sea in 2017–2021 in the period of Cyanobacterial bloom

The structure and dynamics of plankton communities in the coastal zone of the Curonian Lagoon of the Baltic Sea in January-December 2017–2021 was studied. It was found that at the coastal shallow littoral station surrounded by macrophytes the species diversity was higher, and the quantitative characteristics of phytoplankton and zooplankton were lower in all seasons and years of the study than at the deeper coastal station located behind the macrophyte belt. The exception was the period when, as a result of surge events, the phytoplankton biomass in the coastal littoral in October–November 2018 increased to 326–627 g/m3. Every year, “blooms” of water by Cyanobacteria with different intensity and duration were observed at the Lagoon. The abundant of cells of potentially toxic Сyanobacteria exceeded the World Health Organization standard, as a rule, in the summer months at a deep-water coastal station, especially in 2017–2018. This had a negative impact on the state of the entire ecosystem, primarily on zooplankton organisms, in which communities the proportion of dead individuals increased. Water during the period of Cyanobacterial “blooms” in summer and autumn 2017–2018 also had an acute toxic effect on planktonic test organisms.

In‐field climatic factors driving Sclerotinia head rot progression across different sunflower planting dates

AbstractSclerotinia head rot, caused by Sclerotinia sclerotiorum, is a major disease limiting sunflower production in tropical and subtropical agroecological zones. Sporadic outbreaks across South Africa have resulted in major losses, yet little is known about the in‐field climatic factors driving this infection. Short‐interval, staggered plantings have been proposed as a control method for Sclerotinia head rot, which help to limit the number of plants in a susceptible developmental stage during conducive environmental conditions. However, this complicates field management practices, especially if working at the fringes of a planting window due to delayed rains. This study aimed to investigate the effect of planting date on Sclerotinia head rot progression in monthly plantings across the summer period. Artificial mycelial plug inoculations were performed at the R5.9 flowering stage in an open field. Disease establishment, progression and severity were monitored at 3‐day intervals for 30 days. We show that disease establishment was delayed by low relative humidity or extreme low temperatures in the January and March planting dates where the first lesions were only observed 6 days post‐inoculation. Consistently high temperatures above 27°C also suppressed disease progression and produced low area under the disease progress curve (AUDPC) scores of 75.15 and 29.4 for the October and November planting dates, respectively. These findings suggest that regardless of season or location, selecting a planting date that ensures the sunflower bloom period aligns with the hottest, driest part of the season will probably suppress Sclerotinia head rot in regions with average summer highs above 27°C.

The Effect of Nitrogen Reduction and Applying Bio-Organic Fertilisers on Soil Nutrients and Apple Fruit Quality and Yield

In this study, we investigated the effect of partially substituting inorganic nitrogen with bio-organic fertiliser on the ‘Tianhong2’ Fuji apple planting in Xinjiang. Bio-organic fertiliser was applied, and nitrogen was reduced by 20% (T2), 40% (T3), and 60% (T4) during the blooming and fruit expansion periods with conventionally fertilised fields used as control (T1); soil nutrient, soil enzyme activity, leaf nutrients, fruit quality, and yield were measured. The total nitrogen (TN), total phosphorus (TP), total potassium (TK), total calcium (TCa), available phosphorus (AP), available potassium (AK), and soil organic matter (SOM) contents, as well as the soil catalase (S-CAT), soil uretrase (S-UE), soil saccharase (S-SC), and soil nitrate reductase (S-NR) activities, significantly increased in the experimental soils compared with those in T1. In addition, TP, TCa, and total magnesium (TMg) content in apples significantly increased. Compared to T1, the T2 and T3 treatments significantly improved the fruit yield and quality, increasing the sugar–acid ratio, soluble protein, soluble sugar, peel carotenoid, and anthocyanin content and reducing peel chlorophyll content. The brightness (L*), red–green axis (a*), yellow–blue axis (b*), colour intensity (C), and tone (h°) values changed. The yield per hectare and nitrogen fertiliser partial productivity values were significantly increased. Overall, the T2 treatment resulted in the best outcome for the Yili area. In conclusion, partially substituting inorganic nitrogen with bio-organic fertiliser can effectively increase soil and leaf nutrient content and improve fruit yield and quality.

Retrieval of cherry flowering phenology on Flickr and YouTube: a case study along the Tarumi railway, Gifu, Japan

To further develop the accuracy of monitoring cherry flowering dates, we require phenological records from multiple points in multiple years at the catchment scale, as well as conventional in situ phenological observations, phenological data published on the Internet, and analysis using statistics of Internet search engines. We tried to detect the dates of cherry flowering phenology along the Tarumi railway, Gifu Prefecture, Japan, by using Flickr, an image hosting service, and YouTube, an online video sharing and social media platform. We detected full bloom of Cerasus ×yedoensis and Cerasus jamasakura mainly at cherry blossom viewing spots (around some train stations) on Flickr and at both viewing spots and multiple points in the landscape along the railway on YouTube. Despite local climatological differences along the railway, the detected full blooming dates corresponded not only with each other, but also with the full bloom period of Neodani Usuzumi-zakura (Cerasus itosakura), a famous tree with long-term detailed records. We could not detect the date and location in many photographs on Flickr or in any videos on YouTube. However, the usefulness of both platforms is supported by the facts that we can evaluate the year-to-year variability of full bloom dates, especially at cherry blossom viewing spots, and detect flowering phenology even in a non-photogenic landscape. By applying our method to other railways, we expect to collect multi-year records of plant phenology dates at multiple points that cannot be collected by older methods.

Parthenocarpic fruit quality and production under pollinator-exclusion in southern highbush blueberry

Parthenocarpy is the phenomenon of seedless fruit formation without fertilization. This trait has drawn the attention of many fruit and vegetable breeders due to its ability to overcome insufficient pollination and secure yield. Blueberry (Vaccinium spp.) maintains one of the highest pollination requirements of all crops, demanding growers invest in seasonal pollination services. Nevertheless, blueberry continues to suffer from suboptimal fruit set due to ineffective honeybee pollination, and adverse weather conditions during the brief bloom period. Therefore, developing parthenocarpic blueberry cultivars could provide an economical and effective way to ensure fruit set with decreased dependency on seasonal pollination services. However, the effects of parthenocarpy on berry quality and production-related traits in blueberry is unknown. Therefore, this study aims to evaluate these characteristics in 13 southern highbush blueberry genotypes under two pollination conditions (open-pollination and pollinator-exclusion cages). Open-pollinated and non-pollinated fruits from the 13 blueberry genotypes were assessed for seededness, firmness, size, sugar-to-acid ratio, fruit set, yield, week of peak harvest, and the duration of the fruit development period. Non-pollinated parthenocarpic fruits took longer to develop and tended to be smaller, sweeter, and less firm than open-pollinated fruits. Despite these differences, most parthenocarpic fruits still met market standards. Genotypic differences were also observed, suggesting the opportunity to select for enhanced parthenocarpy in future populations. The results of this study demonstrate that facultative parthenocarpy can be exploited and incorporated into blueberry breeding programs to ensure proper yield in inadequate pollination conditions.

Effect of New Low-cost Polyglutamic Acid fertilizer on Cucumber Growth

Polyglutamic acid produced from the mother liquor of glutamic acid crystals was used as a test fertiliser to study its application in cucumber cultivation. The results showed that the application of polyglutamic acid fertiliser could increase cucumber plant height, plant pitch, number of leaves, root dry matter weight, promote cucumber growth, increase cucumber single melon weight and total yield, and at the same time, it could increase the content of Vc and soluble sugar in cucumber fruits and improve the quality of cucumber. Among them, the application of polyglutamic acid fertiliser increased the plant height of cucumber by 6.3%-39.5% during the flowering period, increased the plant height by 1.8%-12.1% during the melon blooming period, increased the root dry matter weight by 92.8%, increased the weight of single melon by 4.01%-37.12%, and increased the total output by 1.31%-12.87%; the application of two polyglutamic acid fertilisers increased the vitamin C of cucumber fruits by 14.36 % and 28.12 %, and the soluble sugar content by 16.91 % and 35.29 %.

Green Roofs Affect the Floral Abundance and Phenology of Four Flowering Plant Species in the Western United States

This study investigates the potential for green roofs to support pollinator diversity and abundance in urban ecosystems through the altered floral phenology and floral abundance of plants. Floral phenology and the floral abundance of green roof plants are compared to plants grown at grade on the Front Range in Fort Collins, Colorado, and how these changes may affect pollinator biodiversity in urban ecosystems. An independent block design is employed, within one green roof and one ground-level garden, approximately 120 m apart, with replicate plants of 4 species in each garden. Pollinator observations were made weekly during the bloom period for each species. Blue vane traps were used to passively measure pollinator diversity along a transect between the green roof sites and the sites at grade. The total number of flowers per plant is variable between site types, depending on the plant species. However, all species of plants tested bloomed earlier when grown on the green roof than when grown at grade. Pollinator abundance and diversity were low at both site locations. Green roofs may provide foraging opportunities earlier in the season in temperate regions, which can extend the duration of floral foraging opportunities when supported by green infrastructure at grade.

Use of the biostimulant Retard Cherry® as a strategy to delay blooming period in sweet cherry trees

Spring frosts are a limiting factor in sweet cherry production in central-southern Chile. Sweet cherry trees cv. ‘Regina’ and ‘Sweetheart’ were studied to evaluate the effect of foliar application of a biostimulant (Retard Cherry®) prior to leaf fall on the bloom delay, fruit set, fruit drop, yield and quality. Data were compared to a non-product control. The study was conducted in the Maule Region, Chile. Results showed that the use of Retard Cherry® delayed full bloom by 6-8 days between cultivars compared to the control; however, there was no delay in the harvest date. The climatic conditions favored high fruit set (37%-49%) and low fruit drop (63%-70%) between cultivars in both treatments. Regarding fruit quality, no differences in size, soluble solids concentration and color were observed with the product, but a decrease in firmness were observed for ‘Regina’. These results show that Retard Cherry® is an effective tool in delaying bloom, providing trees with more favorable climatic conditions for pollination and fruit set.

FLOWERING LOCUS T genes control floral induction in lotus

The transition to flowering is a vital process in the lotus life cycle that significantly impacts its ornamental value and seed production. However, the molecular basis of floral transition in lotus remains largely unknown. Here, eight homologous FLOWERING LOCUS T (FT) genes were initially characterized in lotus, which were designated as NnFT1–NnFT8. All of these genes were found to possess the conserved PEBP domain and exhibited high transcript levels in both lotus leaves and floral organs. The proNnFT:β-glucuronidase (GUS) assay exhibited GUS staining in the vascular tissues of leaves. Furthermore, subcellular localization revealed that NnFT proteins were present in various cellular organelles, including the nucleus, cytoplasm, and endoplasmic reticulum. Overexpression of two NnFT homologs, NnFT2 and NnFT3, rescued the late flowering phenotype in the Arabidopsis ft-10 mutant, indicating the stimulative roles of NnFTs in floral induction. Moreover, NnFTs demonstrated interactions with a bZIP transcription factor, FLOWERING LOCUS D (NnFD), both in vitro and in vivo. These findings will not only deepen our understanding of the regulatory mechanism underlying lotus floral transition, but also provide valuable genetic resources for creating new lotus varieties with extended blooming periods using molecular strategies in the future.

Assessment of Bee Honey in some Districts in South-Western Nigeria for Agricultural Pesticide Residues and Polycyclic Aromatic Hydrocarbons (PAHs)

Purpose: Honey are produced by honeybees which are expected to be free from contaminants or pollutants in the environment. But different degrees of anthropogenic activities in regions where apiaries domiciles have raised issues of primary health importance because of the increasing contents of pesticide residues, polycyclic aromatic hydrocarbons (PAHs), and other related hydrocarbon compounds in honey. Osun State is an agrarian state where agricultural herbicides and insecticides are used. The study focused on organophosphate and organochlorine compounds and PAHs. Research Method: Honey samples sourced from selected zones in Osun State, were screened for organophosphate, organochlorine compounds, PAHs as well as other related hydrocarbon compounds using Gas Chromatography-Mass Spectrometry (GC-MS). Finding: There were no traces of highlighted pesticide residues except for PAHs and other related compounds. Ninety-two PAHs and other related hydrocarbon compounds were identified. The number of PAHs and related compounds per sample ranged from 9 to 35. While Cyclohexane, Decodane and Naphthalene were the most common with higher concentrations in all the samples. The Mn±S.D values of Cyclohexane, Naphthalene and Decodane obtained were 0.2976±0.1253µgkg-1, 0.471±0.119µgkg-1, and 12.516±3.120µgkg-1 respectively. Other PAHs and other related hydrocarbon compounds identified had insignificant concentrations. Originality/value: The study recommends that bee farmers should locate their apiaries 3km to 5km away from regions where there are serious hazardous anthropogenic activities including industrial areas. Also, there is need for strong understanding between the bee farmers and crop farmers on tolerable uses of agricultural pesticides, and herbicides on field crops during the flower bloom period where there are no options. Lastly, harvested honey should undergo quality assurance and control for safety reasons. All packaged honey for retail should bear labels including the compositions after quality analysis.

An Electrochemical Aptasensor for the Detection of Freshwater Cyanobacteria.

Aphanizomenon is a genus of cyanobacteria that is filamentous and nitrogen-fixing and inhabits aquatic environments. This genus is known as one of the major producers of cyanotoxins that can affect water quality after the bloom period. In this study, an electrochemical aptasensor is demonstrated using a specific aptamer to detect Aphanizomenon sp. ULC602 for the rapid and sensitive detection of this bacterium. The principal operation of the generated aptasensor is based on the conformational change in the aptamer attached to the electrode surface in the presence of the target bacterium, resulting in a decrease in the current peak, which is measured by square-wave voltammetry (SWV). This aptasensor has a limit of detection (LOD) of OD750~0.3, with an extension to OD750~1.2 and a sensitivity of 456.8 μA·OD750-1·cm-2 without interference from other cyanobacteria. This is the first aptasensor studied that provides rapid detection to monitor the spread of this bacterium quickly in a targeted manner.

Diversity of planktonic pro- and microeukaryotes in water bodies of the Volga-Don basin during the period of cyanobacterial bloom according to metabarcoding data

The first data on the phylogenetic diversity of planktonic communities of pro- and microeukaryotes in different types of water bodies of the Volga-Don basin during the period of cyanobacterial bloom are presented. Aphanizomenon flos-aquae/Dolichospermum flos-aquae blooms were found mainly in the Kuibyshev Reservoir; Planktothrix agardhii bloom was observed in floodplain lakes of the majority of investigated rivers. Bloom of Raphidiopsis raciborskii was found in a lake on the Volga River terrace, and in a pond in the floodplain of the Samara River Anabaenopsis dominated anong Cyanobacteria. Among heterotrophic prokaryotes, Proteobacteria, Bacteroidota, Verrucomicrobiota, Planctomycetota and Actinobacteriota predominate in the number of sequences, and among protists - Ciliophora, Gyrista (mainly Chrysophyceae), Cryptista and Myzozoa. During the period of cyanobacterial bloom, the contributions of Proteobacteria (especially, Burkholderiales and Pseudomonadales) and Actinobacteriota slightly decrease, while Myzozoa, on the contrary, increase. Monodominant blooms of various species of cyanobacteria significantly change the composition and structure of microbial communities, both at the OTUs and higher taxa levels. The plankton of the pond with Anabaenopsis bloom is most peculiar. Communities with blooms of P. agardhii, R. raciborskii and A. flos-aquae/D. flos-aquae are more similar to each other.

Fungicide Use Patterns in Select United States Wine Grape Production Regions.

Wine grape production (Vitis sp.) in the United States requires fungicide inputs for disease control. Currently, there is limited data available on vineyard fungicide use patterns. This information is important in developing tailored recommendations for disease management and fungicide stewardship. In this paper, we summarize the wine grape vineyard fungicide use patterns from four major regions: Napa and Sonoma valleys (California), Willamette Valley (Oregon), Columbia Valley (Washington), and several smaller regions east of the Mississippi River in years 2009 to 2020. We learned that the average in-season total fungicide applications ranged regionally from 5.6 to 8. The most commonly applied Fungicide Resistance Action Committee (FRAC) codes in spray programs were FRAC 3, 13, and M02 across all regions, with some variation to the top four groups in each region. Most applications were made on 14-day intervals; however, shorter intervals (7-day) were favored early season, and longer intervals (21-day) were favored late season. Tank-mixing multiple active ingredients was common east of the Mississippi River during all stages of grape development; this action was typically favored during the bloom period in other regions. In a subset of records that participated in FRAC 11 fungicide resistance testing, the average number of FRAC 11 applications after testing was reduced to either no applications or one application in Napa and Sonoma valleys. This survey provides regionally specific data related to fungicide stewardship practices that could be a focus for future stewardship messaging and fungicide resistance selection training, including total product use (selection events), spray intervals (selection pressure), and tank mixing (selection management).[Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Community structure of phytoplankton in different water layers and its relationship with environmental factors during the period of algal bloom in Xiaojiang River backwater area of Three Gorges Reservoir

Community structure of phytoplankton in different water layers and its relationship with environmental factors during the period of algal bloom in Xiaojiang River backwater area of Three Gorges Reservoir

Warming and trophic structure tightly control phytoplankton bloom amplitude, composition and succession.

To better identify the responses of phytoplankton blooms to warming conditions as expected in a climate change context, an in situ mesocosm experiment was carried out in a coastal Mediterranean lagoon (Thau Lagoon, South of France) in April 2018. Our objective was to assess both the direct and indirect effects of warming on phytoplankton, particularly those mediated by top-down control. Four treatments were applied: 1) natural planktonic community with ambient water temperature (C); 2) natural planktonic community at +3°C elevated temperature (T); 3) exclusion of larger zooplankton (> 200 μm; mesozooplankton) leaving microzooplankton predominant with ambient water temperature (MicroZ); and 4) exclusion of larger zooplankton (> 200 μm; mesozooplankton) at +3°C elevated temperature (TMicroZ). Warming strongly depressed the amplitude of the phytoplankton bloom as the chlorophyll a concentration was twice lower in the T treatment. This decline under warmer conditions was most likely imputed to increase top-down control by zooplankton. However, removal of mesozooplankton resulted in an opposite trend, with a higher bloom amplitude observed under warmer conditions (MicroZ vs. TMicroZ) pointing at a strong interplay between micro- and mesozooplankton and the effect of warming for the spring phytoplankton blooms. Furthermore, both warming and mesozooplankton exclusion induced shifts in phytoplankton community composition during bloom and post-bloom periods, favoring dinoflagellates and small green algae at the expense of diatoms and prymnesiophytes. Moreover, warming altered phytoplankton succession by promoting an early bloom of small green flagellates, and a late bloom of diatoms. Our findings clearly highlighted the sensitivity of phytoplankton blooms amplitudes, community composition and succession patterns to temperature increases, as well as the key role of initial zooplankton community composition to elicit opposite response in bloom dynamics. It also points out that warmer conditions might favor dinoflagellates and small green algae, irrespective of zooplankton community composition, with potential implications for food web dynamics and energy transfer efficiency under future ocean condition.

EARLY WARNING SYSTEM (EWS) FOR ALGAL BLOOMS USING SATELLITE IMAGERY IN JAKARTA BAY

Jakarta Bay is experiencing eutrophication, primarily due to nutrient inflows from agriculture, industry, and urban sources. This abundance of nutrients has led to significant algae blooms. A study using Terra and Aqua MODIS satellite data from 2004 to 2007 monitored these blooms by measuring chlorophyll-a levels. During this period, large-scale fish kills were observed directly related to the algal blooms, as evidenced by high chlorophyll-a concentrations and blooms covering more than a quarter of the bay. Interestingly, not all intense blooms resulted in massive fish kills. The study suggests that this mortality is primarily due to oxygen depletion after peak bloom periods, compounded by poor water circulation in the bay. Using satellite imagery to monitor algal blooms is a practical tool for implementing an early warning system (EWS) in Jakarta Bay. Satellite imagery has proven effective in monitoring these blooms and could help develop an early warning system in Jakarta Bay despite limitations such as cloud cover.