Main Dominant Species Research Articles

75-Year dynamics of the Black Sea phytoplankton in association with eutrophication and climate change

Based on a database containing species records obtained from 1948 to 2022 and a hydrochemical database, long-term changes in the biomass and taxonomic structure of phytoplankton in the deep-sea basin of the Black Sea were analysed in the stratified period from April to October. Over 75 years, a significant increase in concentration of nitrate, a weak increase in phosphate and a strong decrease in dissolved silicate were observed in the nutricline. The biomass of diatoms and total phytoplankton increased several times during the peak of eutrophication in 1991–1993, then decreased by the 2000s and has again shown an increasing trend in the last 15 years. The number of species dominant in biomass has halved from the 1940s–60s to the 2010s. The primary beneficiaries were the large- and medium-celled diatoms Pseudosolenia сalcar-avis and Proboscia alata, as well as the coccolithophore Emiliania huxleyi, the main dominant species of the last decade. Most noticeable was the increase in the amplitude and duration of the regular annual May–July bloom of E. huxleyi. Over the past three decades, its biomass has increased by more than an order of magnitude, accounting for about 40 % of the total phytoplankton biomass. Development of the large- and medium-celled diatoms, as well as the decrease in biomass of silicoflagellates, can be, at least partly, associated with the long-term decline in dissolved silicate in the upper layers. The trend towards a decrease in dinoflagellate biomass is probably associated with increased mixing intensity in the water column. Over the study period, the total phytoplankton biomass was positively related to nitrate stock in the water column. Short-term period (from one to several years) interannual variability was influenced predominantly by hydrophysical processes, primarily the intensity of winter convection. After cold winters with intense involvement of deep nutrients in the upper layers, the biomass of diatoms, coccolithophores and total phytoplankton increased. Thus, fluctuations in winter weather or local climate reduced or enhanced the effect of eutrophication, sometimes leading to the time gap between the peak in nitrate stock and phytoplankton biomass. The case of the Black Sea illustrates the complex pattern of the response of a marine ecosystem to the simultaneous impacts of anthropogenic and climate changes, leading to significant alterations in the functioning of the biological carbon pump.

Viral Diversity and Ecological Impact of DNA Viruses in Dominant Tick Species in China.

Ticks are blood-feeding ectoparasites that also transmit various pathogens, posing severe risks to human and animal health. DNA viruses play a crucial role in the microbial ecology of ticks, but their distribution and ecological significance remain largely undetermined. Here, we assembled an extensive catalog encompassing 4320 viral operational taxonomic units (vOTUs) from six main dominant tick species in China, of which 94.8% have not been found in any other environment. To bridge the knowledge gap in tick DNA virus research and provide a crucial resource platform, we developed the Tick DNA Virus Database. This database includes the vOTUs that are known to cause diseases. Most of the predicted vOTUs are associated with dominant bacterial and archaeal phyla. We identified 105 virus-encoded putative auxiliary metabolic genes (AMGs) that are involved in host metabolism and environmental adaptation, potentially influencing ticks through both top-down and bottom-up mechanisms. The identification of microbial communities and antibiotic resistance in wild tick species suggests that wild ticks are reservoirs of antibiotic resistance and potential spreaders of antibiotic resistance. These findings reveal the potential role of tick viruses in ecosystems, highlighting the importance of monitoring tick microbiomes to address global public health challenges.

Pre-drought effects on northern temperate trees and vine invasion in forest gaps hindering regeneration

Northern temperate coniferous forests serve as crucial connectors between boreal and temperate forests, yet they are vulnerable to various stressors such as climate change and human activities. Severe drought poses a significant threat to plant species within these forests, prompting recent research into its impacts. However, many studies lack explicit definitions of post-disturbance vegetation processes and fail to identify potential interactions with disturbance factors, necessitating comprehensive discussions. This study examines the effects of drought on tree growth patterns of the main dominant species in northern temperate regions: Abies nephrolepis and Picea jezoensis, along with two commonly associated Betula ermanii, and Quercus mongolica. Additionally, new disturbance factors in forests inhabited by these species (A. nephrolepis and P. jezoensis) were evaluated based on community classification. The study sites were located in the Mt. Baekdu (Changbai) and South Korea regions, which are positioned at the southern limit of the phytogeographical patterns of target species. Results indicate that A. nephrolepis and P. jezoensis exhibit high levels of recovery and resilience, while B. ermanii and Q. mongolica demonstrate high resistance. Species-specific responses align with drought intensity, with resistance, recovery, and resilience decreasing notably with increasing pre-drought radial growth. South Korean forests, the invasion of the vine species Tripterygium regelii after the death of A. nephrolepis in the overstory vegetation threatens the regeneration of new trees. However, certain environmental factors, such as high rock exposure and dense overstory canopy, limit vine invasion. Based on the results, pre-drought radial growth emerges as a key determinant in how trees respond to drought. Additionally, the results suggest the potential for new disturbances to emerge in forest gaps due to overstory vegetation mortality induced by global warming. These findings contribute to a deeper understanding of increasing drought stress, aid in identifying climate refugia, and inform conservation priorities based on habitat characteristics.

Impact of Nutrient Enrichment on Community Structure and Co-Occurrence Networks of Coral Symbiotic Microbiota in Duncanopsammia peltata: Zooxanthellae, Bacteria, and Archaea.

Symbiotic microorganisms in reef-building corals, including algae, bacteria, archaea, fungi, and viruses, play critical roles in the adaptation of coral hosts to adverse environmental conditions. However, their adaptation and functional relationships in nutrient-rich environments have yet to be fully explored. This study investigated Duncanopsammia peltata and the surrounding seawater and sediments from protected and non-protected areas in the summer and winter in Dongshan Bay. High-throughput sequencing was used to characterize community changes, co-occurrence patterns, and factors influencing symbiotic coral microorganisms (zooxanthellae, bacteria, and archaea) in different environments. The results showed that nutrient enrichment in the protected and non-protected areas was the greatest in December, followed by the non-protected area in August. In contrast, the August protected area had the lowest nutrient enrichment. Significant differences were found in the composition of the bacterial and archaeal communities in seawater and sediments from different regions. Among the coral symbiotic microorganisms, the main dominant species of zooxanthellae is the C1 subspecies (42.22-56.35%). The dominant phyla of bacteria were Proteobacteria, Cyanobacteria, Firmicutes, and Bacteroidota. Only in the August protected area did a large number (41.98%) of SAR324_cladeMarine_group_B exist. The August protected and non-protected areas and December protected and non-protected areas contained beneficial bacteria as biomarkers. They were Nisaea, Spiroplasma, Endozoicomonas, and Bacillus. No pathogenic bacteria appeared in the protected area in August. The dominant phylum in Archaea was Crenarchaeota. These symbiotic coral microorganisms' relative abundances and compositions vary with environmental changes. The enrichment of dissolved inorganic nitrogen in environmental media is a key factor affecting the composition of coral microbial communities. Co-occurrence analysis showed that nutrient enrichment under anthropogenic disturbances enhanced the interactions between coral symbiotic microorganisms. These findings improve our understanding of the adaptations of coral holobionts to various nutritional environments.

Unlocking the therapeutic potential of Huoxiang Zhengqi San in cold and high humidity-induced diarrhea: Insights into intestinal microbiota modulation and digestive enzyme activity

Huoxiang Zhengqi San (HXZQS), a traditional Chinese herbal formula, enjoys widespread use in Chinese medicine to treat diarrhea with cold-dampness trapped spleen syndrome (CDSS), which is induced by exposure to cold and high humidity stress. This study aimed to explore its therapeutic mechanisms in mice, particularly focusing on the intestinal microbiota. Forty male SPF-grade KM mice were allocated into two groups: the normal control group (H-Cc, n = 10) and the CDSS group (H-Mc, n = 30). After modeling, H-Mc was subdivided into H-Mc (n = 15) and HXZQS treatment (H–Tc, n = 15) groups. Intestinal samples were analyzed for enzyme activity and microbiota composition. Our findings demonstrated a notable reduction in intestinal lactase activity post-HXZQS treatment (P < 0.05). Lactobacillus johnsonii, Lactobacillus reuteri, and Lactobacillus murinus emerged as the main dominant species across most groups. However, in the H-Mc group, Clostridium sensu stricto 1 was identified as the exclusive dominant bacteria. LEfSe analysis highlighted Clostridiales vadinBB60 group and Corynebacterium as differential bacteria in the H–Tc group, and Cyanobacteria unidentified specie in the H-Mc group. Predicted microbiota functions aligned with changes in abundance, notably in cofactors and vitamins metabolism. The collinear results of the intestinal microbiota interaction network showed that HXZQS restored cooperative interactions among rare bacteria by mitigating their mutual promotion. The HXZQS decoction effectively alleviates diarrhea with CDSS by regulating intestinal microbiota, digestive enzyme activity, and microbiota interaction. Notably, it enhances Clostridium vadinBB60 and suppresses Cyanobacteria unidentified specie, warranting further study.

Temporal and spatial variations and driving factors of phytoplankton in Yongjiang River estuary

To explore the temporal and spatial variations in phytoplankton community in small estuaries, we collected surface water samples from Yongjiang River estuary during wet, normal, and dry seasons and determined the main driving factors of phytoplankton community. A total of 358 species belonging to nine phyla and 123 genera were identified in all seasons. During wet, normal, and dry seasons, species number was 276, 154 and 151, and the abundance was (170.45±225.43)×103, (51.92±30.28)×103 and (31.65±12.79)×103 cells·L-1, respectively. Diatoms dominated the phytoplankton community, and the main dominant species were Cyclotella meneghiniana, Skeletonema costatum, and Paralia sulcata. Shannon diversity and Pielou evenness indices decreased from inside mouth to outside mouth in wet season, but there was no obvious spatial difference in normal season or dry season. Results of non-metric multidimensional scaling analysis and analysis of similarities showed that phytoplankton community composition differed significantly among different regions (inside, at and outside mouth) and different seasons. In wet season, phytoplankton abundance was significantly positively correlated with temperature, dissolved inorganic nitrogen, and dissolved reactive phosphorus, but significantly negatively correlated with salinity. In normal season, phytoplankton abundance was significantly negatively correlated with temperature. In dry season, it was not significantly correlated with environmental factors. Results of redundancy analysis showed that temperature, salinity, ammonium and dissolved reactive phosphorus explained the variations in phytoplankton community by 19.5%, 11.9%, 9.4% and 8.2%, respectively. These results revealed high dominance of diatoms and the main driving factors (temperature, salinity and nutrients) of phytoplankton community in Yongjiang River estuary.

Characteristics of sublittoral vegetation in the northwestern Okhotsk Sea based on the concept of adaptive zone

Sublittoral vegetation in the northwestern Okhotsk Sea is described on the data of diving survey in 2020 and some additional data obtained from 2003 to 2022. Five macroalgae associations (Saccharinetum latissimae, Pseudolessonietum laminarioidae, Alarietum esculentae, Sargassetum miyabeae, and Zosteretum marinae) and one group of red algae communities are identified and classified into 5 alliances, 3 orders and 3 classes. All these associations occur over entire area (from 56º to 59º N), within almost whole range of the surveyed depths (2–11 m), and occupy a total of 88 % of the vegetation cover, with statistically uniform distribution. Coenofloras of the associations are poor: up to 5–6 species or multispecies groups have been noted in every association. The concept of an adaptive zone is proposed as an optimal methodological basis for describing marine sublittoral plant communities in the temperate zone. The sublittoral associations in the study area are considered as elementary Petersen-type communities with on average ¾ of the bottom cover and biomass formed by the main dominant species. These associations and higher syntaxa can be built into the most common floristic system of syntaxonomic classification. The adaptive zone concept allows to solve the problem of subjectivism in selection of syntaxa, so the syntaxonomy becomes closer to natural classification with ecological meaning. Successful applicability of the adaptive zone concept for the algae resources assessment is proven; the stock in the surveyed area of 64 km2 is evaluated as 200 . 103 t.

Study on the soil microbial community structure of the Rhizosphere of Camellia sinensis L. in Anping Village, Kaiyang County, Guizhou Province

BackgroundTo determine the differences in the microbial communities in the Camellia sinensis L. hairy root, lateral root, and main root rhizospheres in Anping Village, Kaiyang County, Guizhou Province, the community structure, diversity, and main dominant species of bacteria and fungi in different parts of the soil were analyzed by ITS and 16S sequencing.ResultsIn the rhizosphere soil of the main root, lateral root, and hairy root of Camellia sinensis L., there were significant differences in the diversity and richness of the bacterial and fungal communities. The bacterial diversity was the highest and the fungal richness was the lowest in the rhizosphere soil of the main root. In the bacterial community, Proteobacteria, Actinobacteria, Acidobacteria, Chloroflexi, and Gemmatimonadetes were the common dominant bacteria. Rhodospirillaceae, Bradyrhizobiaceae, Hyphomicrobiaceae, Solibacteraceae, and Koribacteraceae were the common dominant bacteria in the rhizosphere soil of different parts of the root system, but the relative abundance of bacteria in different parts of the rhizosphere soil varied greatly. The dominant groups of fungal communities in different parts of the rhizosphere soil were Basidiomycota, Ascomycota, Mortierellomycota, and Sebacinaceae. The structure of the fungal community is similar in different parts.ConclusionsCompared with the different parts of the hairy root, lateral root, and main root of rhizosphere soil of Camellia sinensis L. in Anping village, it was found that the abundance of fungal community decreased with the increase of bacterial community abundance, and there were significant differences in bacterial community diversity and structure. However, the fungal community maintained stability among different parts.

Effects of Chinese herbal medicines on growth performance, intestinal flora, immunity and serum metabolites of hybrid grouper (Epinephelus fuscoguttatus♀×Epinephelus lanceolatu♂).

The immunomodulatory roles of Chinese herbal Medicine (CHM) in aquatic animals have been well-recorded. However, how CHM impacts the intestinal microbiota and serum metabolism is not fully understood. In this study, the effects of different additive levels of CHM on the growth performance, immunity, intestinal flora and serum metabolism of hybrid grouper (♀Epinephelus fuscoguttatus×♂Epinephelus lanceolatu) were investigated. The addition of 0.5%, 1.0%, 1.5% and 2.0% Chinese herbal medicine compound to feed could significantly improve the weight gain rate (WGR), specific growth rate (SGR) and survival rate (SR) of grouper, reduced feed coefficient, while had no significant difference on morphometric parameter. The most significant improvement for the parameters above was observed in 1.5% group. Different addition levels of CHM could also significantly enhance the activities of ACP, AKP, SOD, CAT and LZM in serum. Accordingly, the supplementation of CHM significantly induced up-regulation of immune genes such as IL-8, IL-1β, TNF-α, Nrf2, Lzm in the liver, spleen and head kidney of grouper, improved the resistance of grouper to V. harveyi as well. The intestinal flora analysis showed that at the phylum level, the main dominant species of intestinal microorganisms were Firmicutes, Proteobacteria, Bacteroidota, Actinobacteriota, Gemmatimonadota, Desulfobacterota, Fusobacteriota and Myxococcota. At the genus level, the high abundance was Lactobacillus, Streptococcus, Bacteroides, Escherichia, Romboutsia, Sphingomonas and Muribaculaceae. The abundance of probiotics (such as Lachnospiraceae, Lactobacillaceae, Streptococcaceae, etc) in CHM-supplement groups were higher (highest in 1.5% group) compared with control group. Moreover, a total of 11 common differential metabolic pathways were screened by LC-MS metabolism analysis of serum, they were Neuroactive ligand-receptor interaction, Purine metabolism, Linoleic acid, Glycerophospholipid metabolism, Taurine and hypotaurine metabolism, Arginine and proline metabolism, ABC transporters, Aminoacyl-tRNA biosynthesis, Arachidonic acid metabolism, Drug metabolism-cytochrome P450, alpha-Linolenic acid metabolism. Also, three common differential metabolites (PI(20:4(5Z,8Z,11Z,14Z)/18:1(11Z)), PC(20:3(8Z,11Z,14Z)/22:1(13Z)), PC(22:0/20:4(5Z,8Z,11Z,14Z)) associated with intestinal health, growth and disease resistance was found. These data will contributes to a comprehensive understand for the regulatory roles of CHM on fish, which is also beneficial for the disease control and sustainable development of aquaculture.

Effects of Climate Change and Nitrogen Addition on Carbon Loss in Alpine Wetland of Qinghai–Tibet Plateau

Soil microorganisms and soil organic carbon (SOC) play important roles in ecosystem cycling, but there is a lack of clarity about the effects of nitrogen addition on soil microorganisms and SOC, as well as the key microbial taxa that influence SOC. This study was conducted in the alpine wetland of Xiaopo Lake in the Qinghai Lake basin, using NH4NO3 as the nitrogen source, three nitrogen addition gradients (N2: 2 g/m2, N5: 5 g/m2, N10: 10 g/m2), and a blank control treatment (N0: 0 g/m2), with three replicate experiments for each treatment. The main findings were as follows: (1) Both increased soil temperature and decreased precipitation reduced SOC content. SOC content gradually decreased with increasing nitrogen concentration; SOC was reduced by 3.36–29.54% and 8.57–26.66% at 0–15 cm and 15–30 cm soil depths, respectively. (2) Proteobacteria, Chloroflexi, Acidobacteria, and Actinobacteria were the main dominant species, and their changes determined the changes in the entire bacterial community. The relative abundance of Proteobacteria and Actinobacteria decreased under nitrogen addition; Acidobacteria increased significantly; and Chloroflexi did not change significantly. The overall abundance and diversity of soil bacteria showed an increasing trend. The number of soil bacteria is a key factor affecting SOC content, and an increase in the number and diversity of soil bacteria enhances their decomposition capacity, and thus, reduces SOC content. (3) Increased soil temperatures and decreased precipitation are associated with decreased SOC and are the main climatic factors affecting SOC. This study provides a reference for the rational utilization and management of wetland ecosystems under climate change.

Projecting future aboveground carbon sequestration rate of alpine forest on the eastern Tibetan Plateau in response to climate change.

The aboveground carbon sequestration rate (ACSR) of forests serves as an indicator of their carbon sequestration capacity over time, providing insights into the potential carbon sequestration capacity of forest ecosystems. To explore the long-term Spatiotemporal variation of ACSR in the transitional ecotone of theeastern Tibetan Plateau under climate change scenarios, we utilized a forest landscape model that was parameterized with forest inventory data from the eastern Tibetan Plateau to simulate this ecological function changes. The study found that climate warming had significant effect on forests ACSR in different types of forests. ACSR was significantly reduced (p<0.05) in cold temperate coniferous and temperate coniferous forests, whereas it was significantly increased in deciduous broad-leaved forests. However, the impact of climate warming on evergreen broad-leaved forests was found to be negligible. At the species level, climate warming has mostly suppressed the ACSR of coniferous trees, except for Chinese hemlock. The main dominant species, spruce and fir, have been particularly affected. Conversely, the ACSR of most broad-leaved trees has increased due to climate warming. In addition, at the landscape scale, the ACSR within this region is expected to experience a steady decline after 2031s-2036s. Despite the effects of climate warming, this trend is projected to persist. In conclusion, the forests ACSR in this region will be significantly affected by future climate warming. Our research indicates that climate warming will have a noticeable suppressive effect on conifers. It is imperative that this factor be taken into account when devising forest management plans for the future in this region.

The contribution of common and rare species to species abundance patterns in alpine meadows: The effect of elevation gradients

Ecological niche modeling uses environmental variables associated with species distribution points to simulate species distribution and its importance in biodiversity conservation. This study aimed to quantify plant community composition and species abundance distribution (SAD) in alpine meadows at different elevations and to assess the contribution of rare and common species to SAD. We established a permanent study plot of 210 hm2 in Gannan Tibetan Autonomous Prefecture, China, surveyed 315 sample squares (0.5 m × 0.5 m), and calculated the Hill numbers. The results showed that (1) a total of 72 species were surveyed at different altitudes, with Kobresia humilis and Kobresia macrantha as the main dominant species; (2) the SADs of overall and common species fit the ecological niche model (GSM (Geometric Sequence Model)), indicating that ecological niche differentiation is the main factor influencing SAD. The fitted model for rare species SAD varied with elevation, suggesting that various ecological processes influence rare species SAD. (3) Hill numbers showed a “single peak” pattern with increasing elevation. The number of rare species was higher than that of common species. Still, the distribution frequency of common species was significantly higher than rare species. The correlation between common-rare species sequences and cumulative species distribution was high. This indicates that common species dominate the species diversity pattern of the community, are the main contributors to the SAD pattern, and should be protected first. Rare species are also important carriers of community function and include much spatial information. Rare and common species work together in different ways to influence and maintain the species diversity patterns of alpine meadow plant communities.

Stand Structure Management and Tree Diversity Conservation Based on Using Stand Factors: A Case Study in the Longwan National Nature Reserve

The management of stand structure and the protection of species diversity are crucial to forest ecosystem service functions. Changbai Mountain is one of the three major forest regions in Northeast China, and understanding the characteristics of stand structure and the allometric relationship between stand structure variables and the correlation between stand factors and species diversity is the basis for achieving effective forest management and ecological function improvement. In this study, the typical deciduous broad-leaved mixed forest and coniferous and broad-leaved mixed forest of the Longwan Nature Reserve in the Changbai Mountain were taken as the research objects, and the stand structure and diversity were investigated in detail. Allometric growth equations were established using the breast height diameter (DBH), tree height, and crown width of the main dominant species. Pearson correlation analysis was conducted on the stand structure and diversity of the forest community. The experimental results showed that young forests with small diameters and small individuals were the main part of the stands. Optimal allometric growth models of the main tree species (Acer mandshuricum, Ulmus davidiana var. japonica, Juglans mandshurica, Acer mono, and Tilia amurensis) were 0.807D0.646, 0608D0.381H0.390, 0.502D0.533H0.295, 0.795D0.540H0.157, and 0.541D0.484H0.301, respectively, with R2 values ranging between 0.6 and 0.8, indicating a good fit for the models. Furthermore, tree density, crown width, and DBH were the main factors affecting tree diversity. The research results will provide theoretical support for the efficient management of forest stand structure and diversity conservation in the Longwan Reserve.

Morphology, growth, and photosynthesis of Ulva prolifera O.F. Müller (Chlorophyta, Ulvophyceae) gametophytes, the dominant green tide species in the Southern Yellow Sea

Green tide with the main dominant species is Ulva prolifera O.F. Müller have been reported in the Southern Yellow Sea since 2007. This study investigated differences in the morphology, growth, chlorophyll fluorescence parameters, and chloroplast pigment content of different day-aged U. prolifera gametophytes. Gametes had two flagella and exhibited positive phototaxis. On the 7th day of culture, young gametophytes began to branch out. Changes in the length and width of the main branches, and the length of the first-level branches showed “S”-shaped growth within 0–30 days, while the fresh weight of single algae exhibited “J”-shaped growth. The average fresh and dry weight of U. prolifera was 12.32 and 1.38 g per thallus, respectively, when cultured from one gamete to 30 days. The average number of first-level branches of 10-day-aged thalli was 119 per blade, and the maximum branching level was one. The average number of first-level branches of 30-day-aged thalli was 243 per thallus, and the maximum branching level was five. Except for the NPQ and IK values of 0 d thalli compared with 10 d thalli, the IK value of 0 d compared with 20 d, the NPQ, ETRmax and IK value of 10 d compared with 20 d, and the Alpha value of 10 d compared with 30 d, the Fv / Fm, YII, NPQ, ETRmax, IK and Alpha values of the other 0 d, 10 d, 20 d and 30 d thalli showed significant or extremely significant differences. There was no significant difference in the Chl b / Car value between 0 d and 10 d, the Chl b value between 10 d and 20 d, the Chla / Car value between 10 d and 30 d, and the Car value between 20 d and 30 d was significantly different. The Chl a, Chl b, Car, Chl a / Chl b, Chl a / Car and Chl b / Car values of the other 0 d, 10 d, 20 d and 30 d were highly significantly different. These results not only verify that U. prolifera gametophytes can directly develop into new thalli by parthenogenesis, but also reveal the morphological and physiological characteristics of different day-aged gametophytes. In addition to presenting the typical morphology of different-day-aged gametophytes, this study also reports significant differences in growth, chlorophyll fluorescence parameters, and chloroplast pigment contents among them. This revealed the physiological mechanism of varying growth rates of different day-aged U. prolifera. These findings provide essential reference information for green tide prevention and outbreak mechanism research.

Study on protection of forest plants from pests inhabited in the dry part of the Aral Sea

34 types of pests were found on haloxylon and other sand-retaining plants planted in the dry area of the Aral Sea. The main dominant species of these pests are large and small haloxylon humpback grasshoppers. When the insecticide Imitrin 20% sus.K. was tested on humpback grasshoppers at 0.05 L/ha distribution patter measurement against 2-3-year-old nymphs of grasshoppers and 0.1 L/ha against 4-5-year-old nymphs: after 3 hours - 89.2-87.4%, 24- 95.1-94.0% after 72 hours - 96.3-95.6% biological efficiency was obtained respectively. This preparation has been recommended to produce at the specified measures and periods.

DISTRIBUTION AND GEOBOTANICAL STUDIES OF THE MEDICINAL PLANT CAPPARIS HERBACEA WILLD. IN THE SOUTHERN REGIONS OF KAZAKHSTAN

Conservation of biodiversity has now become one of the most important issues in the world. Among them, the conservation of medicinal plants requires special protection. Today, medicinal plants are widely used in scientific medicine. Its main purpose is to prepare medicinal preparations on the basis of medicinal plants. Huge territories of Kazakhstan are provided with rich natural diversity. Our country has unique plants, adapted to life in the desert. In addition, the flora is rich in forest and steppe species. In recent years, the country's environmental problems have become more complex. The issue of conservation of medicinal plants is a pressing environmental concern. The pharmaceutical industry in Kazakhstan is still in need of development. Therefore, the development of the pharmaceutical industry has become an urgent issue in the country. Intensive integrated use (highland pastures, hayfields, developed cattle breeding, as well as use as a recreation area) of mountain and foothill territories, has caused significant anthropogenic changes in flora and vegetation in recent years. The relevance of the study, is the study of the medicinal plant Capparis heerbacea Willd. which grows mainly in the deserts, semi-deserts and steppes of Central Asia and Kazakhstan. This species is well adapted to different abiotic conditions and was therefore selected for the present study. The research work was carried out in 2020-2022. Classical botanical methods were used in the work. These include: route surveys, ecological systematics, ecological geography, methods of studying cenopopopulations. As a result of research work communities are characterized by the following data: Populations which are in Turkestan region and grow in disturbed areas, gradually increase the number of their individuals and thereby restore the local flora or form the conditions for the formation of new communities and populations of other species. And in the Kyrgyz Alatau population, the ecological condition is stable, which is shown by the mosaic distribution of the study species. The study showed that C. herbacea can be one of the main dominant species for a particular area or locality and an edificator for some ephemeral or ephemeroid species.

Unravelling Nutrients and Carbon Interactions in an Urban Coastal Water during Algal Bloom Period in Zhanjiang Bay, China

Nutrients and carbon play important roles in algal bloom and development. However, nutrients and carbon interactions in the period of the spring algal bloom are not well understood. The aim of this study is to explore the nutrients and carbon interactions in the period of the spring algal bloom covering an urban Jinsha Bay (JSB) coastal water in Zhanjiang Bay (South China Sea) using in situ multidiscipline observation. The results showed that the average concentration of total nitrogen (TN), total phosphorus (TP), and dissolved silicon (DSi) was 97.79 ± 26.31 μmol/L, 12.84 ± 4.48 μmol/L, and 16.29 ± 4.00 μmol/L in coastal water, respectively. Moreover, the average concentration of total dissolved carbon (TDC), dissolved inorganic carbon (DIC) and organic carbon (DOC) in JSB was 2187.43 ± 195.92 μmol/L, 1516.25 ± 133.24 μmol/L, and 671.13 ± 150.81 μmol/L, respectively. Furthermore, the main dominant species were Phaeocystis globosa and Nitzschia closterium during the spring algal bloom. Additionally, the correlation analysis showed salinity (S) was significantly negatively correlated with nutrients, indicating that nutrients derived from land-based sources sustained spring algal bloom development. However, as the major fraction of TDC, DIC was significantly positively correlated with S, which was mainly derived from marine sources. Besides, the algal density showed a significant positive correlation with temperature (T) (p &lt; 0.001) and dissolved oxygen (DO) (p &lt; 0.001), but a significant negative correlation with DIC (p &lt; 0.05), suggesting that spring algal blooms may be simulated by water T increase, and then large amounts of DIC and nutrients were adsorbed, accompanying DO release through photosynthesis in coastal water. This study revealed nutrients and carbon interactions in the spring algal bloom of urban eutrophic coastal water, which has implications for understanding the nutrients and carbon biogeochemical cycle and algal bloom mitigation under climate change and anthropogenic pressures in the future.

Microbial community composition and environmental response characteristics of typical brackish groundwater in the North China Plain

(Objective)To reveal the microbial community composition of regional shallow porous brackish groundwater and its response characteristics to groundwater environment, (Method)the first and second aquifers in Taocheng District, Hengshui City were selected, and 10 groundwater source samples were collected for hydrochemical analysis and microbial 16S RNA gene V4-V5 regional sequencing. (Results)The results showed that the shallow brackish groundwater in the study area is weakly alkaline and has high ion content. The spatial zonation of the abundance and diversity of groundwater microorganisms is obvious. The number of endemic bacteria in groundwater from upstream, midstream to downstream is 11, 135 and 22 respectively, with a total of 22 bacteria. Proteobacteria is the most dominant in groundwater level, and there are obvious differences in different sections. At the genus level, the main dominant species in each group and sample are Pseudomonas and Hydrogenophaga. In terms of composition difference, Pseudohongiella, Pseudorhodobacter and Limnohabitans are the representatives of UR, MR and LR. (Conclusion)On the whole, the composition of flora in groundwater is sensitive and closely related to hydrochemical processes. Species abundance is affected by alkaline and high salinity environmental indicators, while species diversity is related to depth and DO in weak reduction environment.

Efficient photo-Fenton catalysis using magnetic iron nanoparticles decorated boron nitride quantum dots: theoretical and experimental investigations.

To achieve the efficient removal of pharmaceutical wastes, novel photo-Fenton catalysts, iron-decorated boron nitride quantum dots (Fe@BNQDs) were prepared. Fe@BNQDs were characterized using XRD, SEM-EDX, FTIR, and UV-Vis spectrophotometry. The decoration of Fe on the surface of BNQDs enhanced the catalytic efficiency due to the photo-Fenton process. Photo-Fenton catalytic degradation of folic acid was investigated under UV and visible light. The influence of H2O2, catalyst dose, and temperature on the degradation yield of folic acid was investigated using Response Surface Methodology. Moreover, the efficiency of the photocatalysts and kinetics was investigated. Radical trapping experiments revealed that holes were the main dominant species in the photo-Fenton degradation mechanism and BNQDs played active roles because of their hole extraction ability. Additionally, active species such as e- and O2 -˙ have a medium effect. The computational simulation was utilized to provide insights into this fundamental process, and for this purpose, electronic and optical properties were calculated.

Carbon Stock Assessment in Silvopastoral Systems along an Elevational Gradient: A Study from Cattle Producers in the Sumaco Biosphere Reserve, Ecuadorian Amazon

Silvopastoral system (SPS) has been considered as a sustainable management system contribute to greenhouse gas (GHG) reduction, among other benefits compared with open pasture. However, little research has been conducted on the soil and tree biomass carbon stored in traditional pasture with dispersed trees (PWT) compared with pasture in monoculture (PM). The present study was conducted in the Ecuadorian Amazon Region (EAR), along an elevational gradient from 400 to 2000 masl., within the buffer and transition zone of the Sumaco Biosphere Reserve (SBR), using 71 temporary circular plots of 2826 m2, where 26 plots were stablished in PWT and 45 plots in PM. The main results in PWT show significant differences (p ≤ 0.01) between aboveground carbon biomass (AGCtrees) from 41.1 (lowlands), 26.5 (Middle hills) and 16.7 (high mountains) Mg ha−1 respectively, with an average of 31.0 Mg ha−1 in the whole study area. The total carbon pool along the altitudinal gradient in five components: (AGCtrees), belowground carbon (BGCtrees), pasture carbon (AGClitter+pasture) and carbon in soil components (0–10 and 10–30 cm) for PWT ranged from 112.80 (lowlands) to 91.34 (high mountains) Mg ha−1; while for the PM systems assessing three components (AGClitter+pasture) and carbon in soil components (0–10 and 10–30 cm) ranged from 52.5 (lowlands) to 77.8 (middle zone) Mg ha−1. Finally, the paper shows the main dominant tree species in pasture systems that contribute to carbon storage along elevational gradient and concludes with recommendations for decision-making aimed at improving cattle ranching systems through a silvopastoral approach to mitigate the effects of climate change.