Pond culture of seaweed Sargassum hemiphyllum in southern China

The seaweed Sargassum hemiphyllum is widely distributed throughout the coastal waters of Asia and has high commercial value.In recent years,its natural biomass has declined due to over-exploitation and environmental pollution.To seek for a feasible way to culture this seaweed efficiently,we designed a simple long-line system in a shrimp pond for the culture during winter,and the growth and nutritional composition of the seaweed were examined.Results show that the culture system was durable and flexible allowing S.hemiphyllum to grow vertically off the muddy bottom of the pond.Although the length of pondcultured S.hemiphyllum was inhibited by water depth,the weight-specific growth rate((1.65±0.17)%/d) was nearly three times higher than that of wild plants((0.62±0.19)%/d).The crude protein(6.92%±0.88%) and ash content(21.52%±0.07%) of the pond-cultured seaweed were significantly lower than those of the wild plants(9.38%±0.43% and 26.93%±0.07%,respectively);however,crude fat(1.01%±0.04%) was significantly higher than that of the wild plants(0.87%±0.02%).In addition,the nutritional composition of both pond-cultured and wild S.hemiphyllum was comparable to or even higher than those of other common seaweeds being used as food and/or aquaculture fodder.Future studies shall be focused on the impact of environmental parameters on its growth and nutritional composition.     

Effect of diets on the feeding behavior and physiological properties of suspension-feeding sea cucumber Cucumaria frondosa

Journal of Oceanology and Limnology - The suspension-feeding sea cucumber Cucumaria frondosa has become commercially important in recent years. Finding proper diets is the first important step for...     

Bioremediation and fodder potentials of two Sargassum spp. in coastal waters of Shenzhen,South China

In this study, the bioremediation potentials of two seaweeds (Sargassum hemiphyllum and S. henslowianum) against pollution in a coastal mariculture area of Shenzhen, South China, were investigated by comparing the growth, nutrient bioaccumulation capacity of plants from the seaweed bed (control site) with plants from the fish farm. Results indicated that both species are potential candidates for bioremediation in the fish farm areas in terms of their high growth rates and high bioaccumulation capacities on inorganic nutrients. Both Sargassum spp. contain high levels of crude protein (11.7–14.0%) and crude fat (2.2–2.7%), suggesting high nutritional values. The S. hemiphyllum may serve as a good aquaculture fodder with high nutritional compositions and low heavy metal contents. However, heavy metals (Cr, Pb and Cd) of S. henslowianum exceed the maximum allowable concentrations as aquatic feed, which restricts its fodder application. In general, the results of this study may contribute to the marine pollution bioremediation in the coastal areas of South China, especially in mariculture zones.     

边角后方交会若干问题的探讨

对边角后方交会的多值性问题、危险域问题作了进一步的探讨分析 ,供实际应用参考     

悬高测量及其改进

介绍了悬高测量的基本原理,并针对其在实际应用中存在的问题,提出了一种改进方法。     

环境友好的木材物流系统优化

以集材段运输成本、合理林道网密度等经济模型为基础,建立木材物流系统最低费用模型,计算分析了5种物流模式的费用;依据在研究区定位测定的土壤理化性质指标,计算各集材方式对林地的生态干扰程度;采用专家调查法对5种物流模式进行社会效益评价;应用模糊数学评价法,对5种木材物流模式进行综合评价,计算结果表明,“索道集材 汽车运材”物流模式最优。为构建环境友好的木材物流系统,提供决策依据。     

Phylogenetic diversity and bioactivity of culturable deep-sea-derived fungi from Okinawa Trough

Deep-sea sediments are now recognized as a home for rich and largely microbial community. Recently, it has been believed in an increasing number of studies that...     

对边测量及其精度分析

介绍了对边测量的基本原理,对其精度进行了分析,得出一些有益的结论。     

利用全站仪进行高大建筑物高程基准传递

介绍一种利用全站仪进行高大建筑物精密高程传递测量的新技术。该技术不仅具有简便、快速、高效的特点，而且可以实现平面轴线投测和高程传递一次完成。