山西榆次玉湖公园藻类植物的初步研究

为了了解公园水体中藻类植物分布概况,探寻旅游开发对水体中藻类植物的影响,本文对山西省榆次玉湖公园藻类植物的种类组成进行了初步研究,经鉴定,共有藻类植物54种,隶属于4门,14科,27属。其中,硅藻门的种类最多,有4科,10属,22种,约占总种数的40.74%;其次是绿藻门,有7科,12属,21种,约占总种数的38.89%;蓝藻门有2科,4属,9种,约占总种数的16.67%;黄藻门有1科,1属,2种,约占总种数的3.70%。同时,对玉湖公园藻类植物的分布特点也进行了研究,由于公园内沿湖状况,建筑设施,游人多少的不同,藻类植物的分布也有差异。     

Replacement of living microalgae with spray-dried diets for the marine mussel Mytilus galloprovincialis

Growth experiments were carried out in which juvenile mussels Mytilus galloprovincialis were fed diets composed of spray-dried algal products (Sanders Brine Shrimp) which included Schizochytrium sp. (SZ; Docosa Gold), Spirulina platensis (Sp) [=Arthrospira platensis] and Hematococcus pluvialis (H) either alone or in combination with partial rations of living microalgae. Growth of mussels fed 1/4 ration of living algae plus a mixed supplement of 50/50% w/w SZ:Sp grew significantly (SNK; P<0.05) faster than mussels fed a full live algal ration. Furthermore, growth (both wet weight and dry organic weight increase) of mussels fed diets composed of either 70/30% w/w SZ: ground Sp (GSp; <20 μm) or 25/50/25% w/w H:SZ:GSp was significantly (PLSD; P<0.05) greater than that of mussels fed an equal ration (by dry weight) of living Tahitian Isochrysis galbana.     

蔬菜无土栽培营养液灭菌除藻研究进展

营养液中病原菌和藻类的安全高效灭除是封闭式蔬菜无土栽培的重要技术环节。本文综述了蔬菜无土栽培营养液中病原菌和藻类的种类、侵染方式,不同灭菌除藻技术的原理、发展利用现状,并提出了新的技术途径和若干科学问题,以期为后续深入研究和推广应用提供理论依据。     

水体磷浓度对斜生栅藻生长影响的研究

[目的]研究磷浓度对斜生栅藻生长的影响,以防止和控制"水华"的暴发。[方法]从斜生栅藻细胞数目、藻比增长速率和藻最大现存量几个方面对磷的影响进行分析。[结果]在通常水体情况下,斜生栅藻的生长随着水体磷浓度的升高而加快,斜生栅藻生长的最适磷浓度为2mg/L左右,低浓度和较高的磷浓度都会对斜生栅藻的生长起一定的限制作用。自然水体中当磷浓度达到0.02mg/L就被界定为水体富营养化,这时斜生栅藻就会随着外源磷向水体的输入而生长增快,一般情况的水体磷浓度均低于2.00mg/L。降低自然水体中磷浓度的增加是控制绿藻"水华"暴发的根本措施。[结论]该研究为"水华"的综合治理提供了必要的理论基础。     

喀斯特峡谷地下水特征及雨水蓄水工程的水质情况研究——以贵州省花江峡谷为例

总结了贵州花江喀斯特峡谷石漠化生态治理示范区地下水的发育特征和含水介质的差异,同时选择贞丰县北盘江镇马刨井和关岭县板贵乡万年坟火龙果基地两地地下水和雨水蓄水池的水质进行了检测.结果显示,以裂隙地下水为水源的马刨井水池各项检测指标均达到国家饮用水标准要求,而以雨水为水源的万年坟火龙果基地水池在悬浮颗粒物、pH、耗氧量等指标达不到饮用水标准.藻类的生长导致pH随光照变化而变化,正午时达到最大.而夜晚由于呼吸作用使得耗氧量增大,藻类的生长使得雨水蓄水的水质达不到饮用水标准,仅适用于农业灌溉.由此,提出改进措施保证蓄水水质.     

Stratospheric ozone, ultraviolet radiation, and cryptogams

The stratospheric ozone layer, which protects the biosphere from biologically active (mostly harmful) ultraviolet-B (UV-B) solar radiation, thinned during the latter half of the 20th century. In this paper some of the effects of UV-B radiation on cryptogams (cyanobacteria, algae, lichens, mosses, liverworts, pteridophytes and fungi) are reviewed. Effects vary among species, and therefore changes in UV-B radiation may affect species frequencies. Effects also depend on other factors, such as water conditions.     

Mitigation of salinity stress effects on growth,yield and nutrient uptake of wheat by application of organic extracts

ABSTRACT

The reduction of the plant performance was observed in plant growth and yield with reduction in the plant’s production of at least 20% of irrigated land worldwide due to the salinity, so it is the major abiotic stresses. For promoting growth and increasing crop yield natural extracts were used in agriculture and horticulture as bio-stimulants. At the Experimental Farm of the Faculty of Agriculture Zagazig University, a pot experiment has been done under greenhouse condition for studying the spray of natural extracts; moringa leaves extract (MLE); algae extract (AE); licorice root extract (LRE) and propolis extract (PE) on yield, photosynthetic pigments and nutrient uptake of wheat grown on saline soil taken from Abou Hammad county, El-Sharkia Governorate, Egypt. Results showed that spraying with different organic extracts significantly increased yield, protein content, photosynthetic pigments and nutrient uptake as compared to untreated plants. Spraying with MLE gave an increase of all parameters i.e., yield, protein content, NPK, Fe, Zn, and Mn accumulation of wheat plants. The highest increases in grain yield were 81%, 110%, 78% and 50%, caused by MLE, AE, LRE and PE, respectively.     

3种淡水贝类对藻类消除作用的初步研究

本实验比较了褶纹冠蚌、三角帆蚌与河蚬等3种淡水贝类24h内对水族箱中藻类的消除量、消除率及0～4h对藻类的消除效率(Ki)。结果表明:褶纹冠蚌、三角帆蚌与河蚬第24h对藻类的消除率分别达到(74.3±2.9)%、(75.6±2.1)%、(88.4±3.1)%,3种淡水贝类对藻类的消除效果显著;t检验表明,24h内河蚬对藻类的消除率、消除量显著大于褶纹冠蚌和三角帆蚌(P<0.05);河蚬实验组0～4h消除效率(Ki)显著大于褶纹冠蚌和三角帆蚌(P<0.05);三角帆蚌对藻类的消除量随着贝类密度的增加显著增加,河蚬、褶纹冠蚌对藻类的消除效果受密度制约,12h后河蚬20g/L实验组对藻类的消除量最大,褶纹冠蚌40g/L实验组对藻类的消除量最大。     

海藻多糖对肉杂鸡免疫功能的影响

探讨海藻多糖对肉杂鸡的免疫功能的影响。方法：选用1日龄健康AA鸡与新罗曼蛋鸡杂交鸡150只,随机分成Ⅰ、Ⅱ、Ⅲ3组（每组50只）。Ⅰ组按每只每天饮水中添加20mg海藻多糖,Ⅱ组按每只每天饮水中添加20mg黄芪多糖,Ⅲ组饮自来水。分别在21、42日龄每组随机选5只称重后,心脏采血,用于白细胞、淋巴细胞转化率和抗体水平测定;并立即剥离胸腺、法氏囊和脾脏,称重。结果：Ⅰ组与Ⅲ组相比,海藻多糖组在21、42日龄都能显著提高免疫器官系数（P〈0.05）、抗体水平（P〈0.05）、血液淋巴细胞数量（P〈0.05）,其中对脾脏系数、血液白细胞数量差异极显著（P〈0.01）。Ⅰ组与Ⅱ组相比,海藻多糖在21、42日龄都能显著提高血液白细胞数量（P〈0.05）、脾脏系数（P〈0.05）。在42日龄抗体水平异极显著（P〈0.05）。结论：海藻多糖能促进免疫器官的发育,显著提高血清抗体水平和白细胞数量、淋巴细胞转化率。说明海藻多糖具有提高肉鸡免疫功能的作用。     

失水干燥对紫菜等海藻光合作用、呼吸作用及生长的影响

室内晾干不同时间(2—12小时)四种海藻失水达90％。晾干2—12小时对紫菜的毛光合有促进作用。晾干7小时内对石莼的毛光合有促进作用,8小时出现抑制作用;晾干5小时内对礁膜的毛光合有促进作用,6小时出现抑制作用;不同时间晾干的孔石莼电光合均低于对照。晾干2—12小时,四种海藻的净光合速率均有下降,而呼吸作用均受到了不同程度的促进。