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By analyzing the species composition, distribution, quantity and changes of phytoplankton and zooplankton in the coastal waters of Rizhao City in May and August 2021, this paper provides technical support for comprehensively understanding the status and development trend of biodiversity in the coastal waters of Rizhao City in spring and summer. It is of great significance to understand the status of marine biodiversity, the health of ecosystem and the carrying capacity of marine environment in Rizhao City.

Intercropping has the potential to improve phosphorus (P) uptake and crop growth, but the potential benefits and relative contributions of root morphology and arbuscular mycorrhizal fungi (AMF) colonization are largely unknown for the intercropping of rice and soybean under dry cultivation. Both field and pot experiments were conducted with dry-cultivated rice (Oryza sativa L.) and soybean (Glycine max L. Merr.) grown alone or intercropped under two P levels. Two root separation modes between rice and soybean were employed to explore the contribution of AMF association and root plasticity on P uptake in intercrops. The results showed that rice/soybean intercropping resulted in a notable increase in the total biomass and yield compared to monoculture in the field. In the potted experiment, compared to the plastic root separation treatment (PS), the no root separation treatment (NS) increased the total biomass and P uptake by 9.4% and 19.9%, irrespective of the P levels. This was primarily attributable to a considerable enhancement in biomass and phosphorus uptake in soybean by 40.4% and 49.7%, which offset a slight decline in the rice of NS compared to PS by 26.8% and 18.0%, respectively. The results of random forest analysis indicate that the P uptake by the dominant species, soybean, was mainly contributed by root morphology, while rice was more dependent on AMF colonization in the intercropping system. Therefore, dry-cultivated rice/soybean intercropping enhances P uptake and productivity by leveraging complementary belowground strategies, with soybean benefiting primarily from root morphological adjustments and rice relying more on arbuscular mycorrhizal fungi colonization. [ABSTRACT FROM AUTHOR]

Changes in root traits and rhizosphere microbiome are important ways to optimize plant phosphorus (P) efficiency and promote multifunctionality in intercropping. However, whether and how synthetic microbial communities isolated from polyculture systems can facilitate plant growth and P uptake are still largely unknown. A field experiment was first carried out to assess the rice yield and P uptake in the rice/soybean intercropping systems, and a synthetic microbial community (SynCom) isolated from intercropped rice was then constructed to elucidate the potential mechanisms of growth-promoting effects on rice growth and P uptake in a series of pot experiments. Our results showed that the yield and P uptake of intercropped rice were lower than those of rice grown in monoculture. However, bacterial networks in the rice rhizosphere were more stable in polyculture, exhibiting more hub nodes and greater modularity compared to the rice monoculture. A bacterial synthetic community (SynCom) composed of four bacterial strains (Variovorax paradoxus, Novosphingobium subterraneum, Hydrogenophaga pseudoflava, Acidovorax sp.) significantly enhanced the biomass and P uptake of potted rice plants. These growth-promoting effects are underpinned by multiple pathways, including the direct activation of soil available P, increased root surface area and root tip number, reduced root diameter, and promotion of root-to-shoot P translocation through up-regulation of Pi transporter genes (OsPht1;1, OsPht1;2, OsPht1;4, OsPht1;6). This study highlights the potential of harnessing synthetic microbial communities to enhance nutrient acquisition and improve crop production. [ABSTRACT FROM AUTHOR]

The experimental results show that a decrease in the SiO₂/B₂O₃ ration reduced the glass transition temperature, but had little effect on the crystallisation temperature. The basic glass powder pressed into strip samples were sintered at a temperature of 630 to 690 °C. With a decrease in the SiO₂/B₂O₃ ratio, the structure of glass and glass-ceramics changed, and the same change also occurred in the crystal phase in the glass-ceramics. When the SiO₂/B₂O₃ ratio was 0.29, the glass-ceramics sintered at 670 °C reached the best properties, including the bending strength, density, and acid resistance. When the SiO₂/B₂O₃ ratio was 0.29, the coefficient of thermal expansion of the glass-ceramics sintered at different temperatures were maintained in the range of 6.3∼7.2×10-6 K-1.

Green fiber (GF) is a naturally colored fiber. A limited understanding of its color formation mechanism restricts the improvement of colored cotton quality. This experiment used upland cotton green fiber germplasm 1-4560 and genetic inbred line TM-1; the lipid profiles of green fibers at 30 (white stage) and 35 days post-anthesis (DPA) (early greening stage), as well as those of TM-1 at the same stages, were revealed. Among the 109 differential types of lipids (DTLs) unique to GF, the content of phosphatidylserine PS (16:0_18:3) was significantly different at 30 and 35 DPA. It is speculated that this lipid is crucial for the pigment accumulation and color formation process of green fibers. The 197 DTLs unique to TM-1 may be involved in white fiber (WF) development. Among the shared DTLs in GF35 vs. GF30 and WF35 vs. WF30, sulfoquinovosyldiacyl-glycerol SQDG (18:1_18:1) displays a significant difference in the content change between green fibers and white fibers, potentially affecting color formation through changes in content. The enriched metabolic pathways in both comparison groups are relatively conserved. In the most significantly enriched glycerophospholipid metabolic pathway, 1-acyl-sn-glycero-3-phosphocholine (C04230) only appears in white cotton. This indicates differences in the metabolic pathways between white and green fibers, potentially related to different mechanisms of color formation and fiber development. These findings provide a new theoretical basis for studying cotton fiber development and offer important insights into the specific mechanism of green fiber color formation. [ABSTRACT FROM AUTHOR]

We examine how the prior experiences of new venture leaders (NVLs) affect networking behaviors during the early stages of opportunity exploitation. We argue that lack of prior experience increases the unknowns that NVLs face when pursuing opportunity exploitation. Lack of technical experience increases technical unknowns, whereas lack of startup experience increases startup unknowns. Using a qualitative methodology, we investigate 22 NVLs and find that they differ on three dimensions: networking time orientation (short-term vs. long-term), desired benefits (operational vs. symbolic), and networking actions (deepening vs. broadening). We find that novice NVLs, those who lack technical or startup experience, tend to utilize short-term orientation, engage in network-deepening actions, and seek operational benefits from their networks to mitigate technical and startup unknowns. In contrast, dual-experienced NVLs, those with technical and startup experience, are guided by long-term orientations, network-broadening actions, and a focus on symbolic benefits. We also find that technical and startup veterans exhibit a combination of those behaviors. We contribute to the literature by posing a set of three propositions depicting differences in NVL networking behaviors based on differences in startup and/or technical experiences. This study, thus, highlights the influence of NVL experience on early-stage networks. [ABSTRACT FROM AUTHOR]