Public perceptions of ecosystem services and preferences for design scenarios of the flooded bank along the Three Gorges Reservoir: Implications for sustainable management of novel ecosystems

The newly formed extensive flooded land associated with the Three Gorges Reservoir hold great potentials to provide ecosystem services (ESs) for surrounding cities and communities. Conflicting values and conventional management strategies may complicate and inhibit broad-scale decision-making for this novel ecosystem. Public attitudes are a crucial influence in the way this process plays out. This study was conducted to assess how the reservoir bank is perceived by the general public of Chongqing Municipality in terms of importance of riparian ESs, and preference for corresponding landscape design styles through photo-questionnaire interviewing. Although Chongqing citizens know little of the “ecosystem services” concept, they do recognise riparian environmental and ecological benefits especially the bank protection and pollution interception functions, while benefits of habitats for wildlife and flood attenuation were of less concern. Recreational values were least appreciated, which is inconsistent with other studies. This may be attributed to a wider, intensive environmental education in various social media in today’s China. But publicity has been dominated by toxic air, water and soil pollution control rather than the benefits of nature conservation and personal contact with nature. In line with recognition of ESs, there is quite strong preference for the forested design scenario and particularly vegetation components across the socio-demographic spectrum. Overall, socio-demographic variables have very low explanatory power for the perceptual responses. Our study also revealed misunderstandings around riparian functions and a gap between public expectations and special abiotic and biotic prerequisites in restoring novel ecosystems. Finally, we discuss the relevance of this research to urban novel ecosystems in general, and implications for raising public awareness, engaging appropriate public values in sustainable design and management of such ecosystems.     

番茄基因转化中抗生素筛选压力的确定方法

在以抗生素为筛选标记的基因转化中。确定适宜的筛选压力是提高基因转化率的前提。本研究以卡那霉素为例，通过在10mg／L，20mg／L，30mg／L，50mg／L，100mg／L的筛选压力下，转化和非转化番茄子叶外植体的生长表现、愈伤组织和芽的分化率．来确定适宜的筛选浓度。本实验以该方法找到的适宜的卡那霉素筛选浓度为50mg／L。以此浓度为筛选压力进行遗传转化所获得的部分再生苗经southern blot鉴定．均为转化株。     

用牦牛奶生产Scamorza奶酪技术研究

以新鲜牦牛乳为原料,研究了Scamorza奶酪的制作技术,采用四因素三水平正交试验的方法,研究了不同量的凝乳酶、氯化钙、食盐以及发酵温度对成品的口感、色泽质地的影响,最终确定了该产品生产的最佳配方及技术条件:凝乳酶0.003%、氯化钙0.01%、食盐22%,发酵温度为32℃.     

Practical use of response surface methodology for optimization of veterinary antibiotic removal using UV/H2O2 process

Three of the most commonly used veterinary antibiotics—enrofloxacin (ENR), sulfamethoxazole (SMX), and oxytetracycline (OTC)—were chosen as representative antibiotics for UV/H₂O₂ treatments. The objective was to determine the optimization of UV/H₂O₂ to remove antibiotics from aquaculture discharge water using response surface methodology. The degradation of the antibiotics was investigated under varying UV/H₂O₂ conditions in environments with different levels of pH, water matrices, humic acid, and constituent ions. The degradation results demonstrated that increasing the H₂O₂ dosage facilitated ENR degradation at a neutral pH while facilitating degradation of SMX and OTC at a slightly acidic pH. The optimum removal conditions for ENR, which was used in all influential effect experiments and the contact tank experiments, was obtained at 10 mM H₂O₂, a pretreated COD of 87.51 mg L⁻¹, and an initial pH of 6.15. Among the tested anions, only the presence of Cl^- showed slight positive effects on ENR degradation, due to the generation of secondary active radicals. During the reaction, the hydroxyl radical (OH) was present at a higher pH while singlet oxygen (¹O₂) was slightly present at a lower pH. The experimental results from H₂O₂ sequential addition indicated that freshly added H₂O₂ could quench the recently generated OH and therefore a high H₂O₂ concentration with frequent adding was not necessary. Our contact system reduced the ENR concentration in both the effluent reservoir and in the UV irradiation zone. The overall results supported the use of the UV/H₂O₂ system to treat remnant antibiotics in the discharge water.     

Effects of periodical application of bioactive peptides derived from cottonseed on performance,immunity, total antioxidant activity of serum and intestinal development of broilers

This experiment aimed to examine the effect of periodical application of bioactive peptides derived from cottonseed (BPC) in comparison with using sub-therapeutic doses of lincomycin and the excessive inclusion of vitamin E on performance, immunity, total antioxidant capacity of serum and intestinal morphology of broiler chickens. A total of 240 one-d-old male broiler chicks with similar initial weight (Ross strain) were randomly assigned to 6 groups (8 chicks/pen): non-treated group (basal diet), basal diet supplemented with 2 mg/kg lincomycin, basal diet supplemented with 50 IU vitamin E, basal diet supplemented with 6 g BPC/kg in starter period, basal diet supplemented with 6 g BPC/kg in starter and grower periods and basal diet supplemented with 6 g BPC/kg throughout the whole experiment. The highest final body weight was obtained in the group supplemented with BPC in starter and grower periods. In the finisher phase, broilers fed the diet containing BPC in the starter period and in the whole trial had significantly (P < 0.05) better feed conversion ratios (FCR). Jejunal villus height was significantly elevated in broilers supplemented with antibiotic (P < 0.001), furthermore it tended to be greater in broilers fed BPC in the starter period. The jejunal villus height-to-crypt depth ratio was significantly (P < 0.01) higher in broilers fed the diet containing antibiotic in comparison to other groups. Humoral immune response against Newcastle disease vaccine tended to be elevated in broilers fed the diet containing BPC in the whole trial (P > 0.05). Broilers supplemented with BPC in starter and grower, and in the whole trial had significantly (P < 0.05) higher antibody titers against sheep red blood cells (SRBC). The highest total antioxidant capacity was obtained in broilers supplemented with the excessive level of vitamin E, furthermore it tended to improve in broilers fed the diet containing BPC in the whole trial. In summary, the results of the study indicated that addition of BPC in broiler diets in the whole trial could improve FCR, immune responses and total antioxidant activity of serum, and BPC could be used in broiler diets as an alternative to in-feed antibiotics.     

泰乐菌素和土霉素在农业土壤中的消解和运移

长期施用禽畜排泄物可导致抗生素在土壤中的积累, 对环境产生不良影响.为了解进入农田后抗生素的去向及残留动态, 选择2个典型农业土壤, 利用田间小区试验, 研究了田间实际状况下泰乐菌素和土霉素2种抗生素在土壤中的消解与运移行为.研究表明, 抗生素在土壤中的消解和运移与抗生素种类和土壤性质有关.抗生素在砂质土壤(清水砂)中的下移明显高于粘壤土(泥质田), 泰乐菌素在土壤中的垂直迁移强于土霉素.表层土壤中抗生素因降解和下移随时间逐渐下降, 消解速率在试验初期大于后期, 并且土霉素消解速率大于泰乐菌素.砂质土壤中抗生素的消解速率在试验初期明显高于粘壤土, 但至试验后期, 二者渐趋相似.田间条件下测得的抗生素消解速率明显低于实验室条件下, 这可能与抗生素进入田间深层土壤后稳定性增加有关.农田施用抗生素初期产生的径流中含较高浓度的抗生素, 但随时间(10 d之内)很快下降至检测下限以下; 试验初期径流中抗生素浓度为泰乐菌素大于土霉素, 砂质土高于粘壤土.     

7种杀菌剂对人参黑斑病菌的抑菌活性研究

[目的]筛选对人参黑斑病菌有较强抑菌活性的杀菌剂。[方法]采用菌丝生长速率法,测试对比7种杀菌剂在不同浓度梯度条件下对人参黑斑病菌的室内抑菌活性。[结果]室内抑菌活性测定结果表明,7种杀菌剂在各自供试的不同浓度处理间均有显著差异;毒力测定结果表明世高的EC50值最小(0.61 mg/L),其次为链霉素和克菌丹,EC50值均小于100 mg/L。[结论]该研究结果为进一步田间药效试验奠定了理论基础。     

鸡屎藤与鱼鳅串和抗生素联合抑菌试验研究

[目的]考察鸡屎藤、鱼鳅串水提物的体外抗菌活性及其与常用抗生素的联合抑菌效果。[方法]以金黄色葡萄球菌CMCC29178和大肠埃希氏菌ATCC25922标准菌株为检测菌,采用微量肉汤稀释法测定其最小抑制浓度(MIC)和联合抑菌指数(FIC)。[结果]鸡屎藤、鱼鳅串水提物对金黄色葡萄球菌和大肠埃希氏菌都具有一定的抑菌效果,与常用抗菌药物合用表现出不同程度的协同或相加效应。[结论]水提法可广泛用于对具有抗菌活性的植物药材的初步筛选。     

绍兴市售酸奶中乳酸菌的分离鉴定及耐药性分析简

[目的]从绍兴市售酸奶中分离并鉴定乳酸菌,研究乳酸菌分离株对6种抗生素的耐药性。[方法]利用MRS培养基迎过稀释法分离酸奶样品中的乳酸菌并进行菌落计数,对分离菌株进行革兰染色和生化反应鉴定,同时采用纸片扩散法进行耐药性分析。[结果]从15种绍兴市售酸奶样品中共分离出31株菌,生化反应鉴定为嗜酸乳杆菌（6株）、保加利亚乳杆菌（7株）、嗜热链球菌（11株）和双歧杆菌（7株）;活菌计数结果显示,4份样品（26．7％）中乳酸菌计数低于国家标准,11份样品（73．3％）中活菌计数符合国家标准规定;耐药性试验结果显示,31株乳酸菌对4种抗生素均有一定程度的耐受性,且90．3％的菌株具有多重耐药性,能耐受2～3种抗生素。[结论]绍兴市售酸奶中乳酸菌已具有一定程度的耐药性,对酸奶产品进行耐药性监测和安全评价已势在必行。     

曼陀罗内生真菌代谢产物抗皮肤致病真菌活性成分研究

[目的]研究曼陀罗植物内生真菌Ym311977菌株代谢产物的抑菌活性及其有效成份。[方法]对Ym311977菌株进行扩大发酵培养,从发酵产物中分离单体化合物,并研究单体化合物对2株皮肤致病真菌的体外抑制活性。[结果]分离到的4种单体化合物中的1种对2株皮肤致病真菌（石膏样小孢子菌、石膏样毛癣菌）的最低抑菌浓度分别为50、200μg/ml;该化合物经1HNMR及13CNMR分析,确定其结构为5-丁基吡啶甲酸,即镰刀菌酸。[结论]该研究首次报道了曼陀罗内生真菌代谢产物镰刀菌酸对2株皮肤致病真菌具有抑制活性。