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This study was performed in order to isolate and identify unknown allelochemicals from Ficus microcarpa, and to investigate the inhibitory to bloom-forming of green alga Chlorella pyrenoidosa. Through gradient elution, fraction C2, whose inhibition of alga growth in diverse extracts was the strongest was shown to cause significant reductions of maximum quantum yield, as well as electron transport rates of C. pyrenoidosa. The study data also showed that the increase of fraction C2 concentration decreased the activity of total superoxide dismutase (SOD), but increased the activities of catalase (CAT) and malondialdehyde (MDA) content. These results demonstrate that the active fraction C2 not only induced the photoinhibition or photodamage of PSII reaction centers, but also triggered the synthesis of reactive oxygen species which may change cell membrane penetrability, thereby leading to the eventual death of C. pyrenoidosa. Furthermore, the gas chromatography/mass spectrometry (GC/MS) analyses showed that the most potential allelochemical in active fraction C2 was 2-Propyl phenol, which may exhibit potent allelopathy.

In order to improve WKH race walking technique, biomechanical measurement, expert interview and literature research were used to analyze the technical elements of WKH race walking. Research conclusions: 1) The speed index characteristic of WKH' s race-walking technique is that when walking slowly, the time of left legs complex step and right leg's complex step is not balanced, and the step frequency of left leg is faster; that the balance of legs was better when walking quickly, and the average stride frequency was faster than that of Lopez. Fast walking and slow walking have the characteristics of short time and fast frequency. 2) The characteristic of the length index of WKH walking technique is that the step length of the left leg and the right leg is unbalanced, and the change of step length is not stable, especially in Taicang race walking trials, the change of step length of the left leg in slow walking is great, and the flexibility of hip is insufficient. The slow walking backswing technique needs to be improved. The off the ground technique is mainly that the knee joint of swinging leg bends too much when off the ground, the hip flexibility is insufficient, and one leg cannot extend fully forward. When walking fast, the distance of one leg forward swing is not balanced. In Taicang race walking trials, the distance of single leg forward swing is large and the distance of backward pedal is insufficient, which leads to the decline of race walking technology and economy. Slow walking left leg swing distance and distance to be adjusted after the kick, the right shoulder and hip flexibility needs to be strengthened training to strengthen the left leg muscle relaxation after the left foot off the ground. When walking slowly, the center of giavity is relatively stable, and when walking fast, the center of gravity fluctuates slightly. 3) WKH race walking technical movement angle index characteristic is: When increases the big arm back swing movement to have the double arm to swing the angle not balanced phenomenon. From slow walking to fast walking, the plantar landing angle was smaller, the forward resistance increased, and the cumulative load of lower limb joints increased. The muscle relaxation degree of the left leg was different with the right leg when walking fast. The muscle relaxation degree of the left leg was more relaxed when walking slowly in Huangshan Race Walking Competition. When the two legs overlap, the bending angle of knee joint of single leg changes greatly in Taicang Race Walking Selection Competition. The angle of the tmnk is not 0° when one foot touches the ground, and it needs to be adjusted to 90° between the trunk and the ground, and the technique of one foot touching the ground needs to be improved. Recommendations: to further strengthen the flexibility of the hip training and four-limb balance training, increase the range of arm back swing, improve the degree of muscle relaxation of the swing leg, fast walking to control the swing leg forward swing distance, leg back pedal distance and the stability of the body center of gravity. [ABSTRACT FROM AUTHOR]

Due to the intensified human activities in coastal areas in recent years, the estuary wetlands have been seriously degraded. The artificial restoration using mangrove plants is considered to be an effective restoration method. The research on soil nitrogen and phosphorus mainly focuses on the natural mangrove wetlands, but there is limited information about the effects of mangrove restoration on it. The combination of field sampling and laboratory experiment were used to analyze total nitrogen and total phosphorus contents under different planting patterns during wetland restoration in Jinjiang estuary, Fujian Province. The results revealed that the total nitrogen and total phosphorus contents were higher than control, and there were significant differences between different mixed-vegetation types and planting densities, which indicated that mangrove restoration promoted their accumulation and the planting patterns could affect their concentrations. Additionally, the complex hy-drological process may also be an important factor in the estuarine areas. [ABSTRACT FROM AUTHOR]

The estuarine phytoplankton composition, spatial and temporal distribution, primary productivity, and their influencing factors were reviewed, and the significance of estuarine phytoplankton in monitoring aquatic environment, biodiversity of estuarine phytoplankton, and edge effect were discussed. Generally, the dominant phytoplankton populations were diatoms and dinoflagellates in estuaries. Microphytoplankton and picophytoplankton played important roles in estuarine ecosystems. Spatial and temporal changes in estuarine phytoplankton species composition and primary productivity were apparent. Several factors including light, temperature, nutrients, herbivory and river flow could influence estuarine phytoplankton production.