滨海湿地生态经济的综合评价模型

通过对生态环境指标与社会经济指标两方面的分析,建立了滨海湿地生态经济的综合评价模型,定量计算了滨海湿地开发前总效益(V)、开发后总效益(V′)以及开发利用的限制因子(H)和评价因子(I),并以浙江省上虞市世纪丘围垦工程为例,对模型进行了验证计算,结果表明:(1)开发前后的大气调节、水文调节、污染物净化、提供生物栖息地等生态环境效益指标(Vee)和旅游休闲、科研教育、提供各种产品等经济效益指标(Vse)影响着对滨海湿地开发前后总效益以及开发可行性的判断;(2)当滨海湿地的开发评价因子I>1时〔I=V′/V=(Vee+′Vse)′/(Vee+Vse)〕,海涂开发后的总效益大于开发前的总效益,海涂开发具有可行性,否则为不宜开发;(3)当滨海湿地开发利用的限制因子H小于0.20时,应限制滨海湿地的开发、利用;(4)上虞市世纪丘海涂湿地的H为0.78,I为2.1,可见该海涂开发后,生态环境效益有所降低,但社会经济效益却大幅度地提高了,说明该海涂的开发是具有可行性的。     

Nutrient maximums related to low oxygen concentrations in the southern Canada Basin

The phenomenon of nutrient maximums at 70～200 m occurred only in the region of the Canada Basin among the world oceans. The prevailing hypothesis was that the direct injection of the low-temperature high-nutrient brines from the Chukchi Sea shelf (＜50 m) in winter provided the nutrient maximums. However, we found that there are five problems in the direct injection process. Formerly Jin et al. considered that the formation of nutrient maximums can be a process of locally long-term regeneration. Here we propose a regeneration-mixture process. Data of temperature, salinity, oxygen and nutrients were collected at three stations in the southern Canada Basin during the summer 1999 cruise. We identified the cores of the surface, near-surface, potential temperature maximum waters and Arctic Bottom Water by the diagrams and vertical profiles of salinity, potential temperature, oxygen and nutrients. The historical 129Ⅰ data indicated that the surface and near-surface waters were Pacific-origin, but the waters below the potential temperature maximum core depth was Atlantic-origin. Along with the correlation of nutrient maximums and very low oxygen contents in the near-surface water, we hypothesize that, the putative organic matter was decomposed to inorganic nutrients; and the Pacific water was mixed with the Atlantic water in the transition zone. The idea of the regeneration-mixture process agrees with the historical observations of no apparent seasonal changes, the smooth nutrient profiles, the lowest saturation of CaCO3 above 400 m, low rate of CFC-11 ventilation and 3H-3He ages of 8～18 a around the nutrient maximum depths.     

Embryonic and larval development of Babylonia formosae habei(Altena and Gittenberger, 1981)(Gastropoda: Buccinidae) on China''s coast

The development of embryos and larvae of Babyloniaformosae habei living along the southeast coast of China is observed under laboratory conditions. The egg masses are laid by females on hard substrate at night and each capsule contains 100-500 eggs. Each egg is 250-280 mm in diameter. The fast two cleavages of the embryo are meridional and equal, and a polar lobe is produced. Larval kidney, which only consists of a single cell, appears during the gastrula stage on each side of the embryo. The right tentacle develops prior to the left one. At 25-27 ℃, an intracapsulate veliger stage is reached about 4.5 d after deposition. The larvae hatch on the fifth day as swimming veligers with a shell length of 360 -500 mm. The newly hatched larva can ingest suspended algal cells from the water column and remains in the pelagic stage for 8-10 d. The newly settled juveniles are 900-1 200 mm in shell length.     

Influence of water logging time on the growth of candel seedlings

Influence ofwaterlogging time on the growth ofKandeliacandel(L.) Druce seedlings grown for 70 d in the artificial-tidal tanks' simulated semidiumal tide under greenhouse is studied. Sand and soil act as the substrate and artificial sea-water with salinity of 15 is used in cultivation. Shorter waterlogging time (inundated for about 2 ～ 4 h) promotes thegrowth of K. candel seedlings, while longer time(inundated more than 8 h) or no waterlogging(0 h) inhibits theirgrowth. The number and length of aerating roots increase with the increase ofwaterlogging time. Under existing condi-tions, the optimalwaterlogging time for the growth of K. canoel seedlings is about 2 ～ 4 h in every tide cycle. Com-pared with other treatments, the 2 h sanded treatments obtain the highest biomass of seedlings, have the lowest massloss ofhypocotyl and broaden the photosynthetic area by increasing the area per leaf after 70-d cultivation. And the soiltreatments have the similar tendeney. However, waterlogging for 8 h in every tide cycle is critieal for normal develop-ment of seedlings. K. candel seedlings are highly tolerant to waterlogging and a proper waterlogging is beneficial to thegrowth ofK. candel seedlings.     

广东雷州珍稀海洋生物国家级自然保护区水体和沉积物中石油类含量与分布特征

为了探讨广东雷州珍稀海洋生物国家级自然保护区海域水体和沉积物中石油类的含量及其分布特征,文章于2017年和2018年分别对保护区海域的石油类进行了调查。结果表明,保护区表层水体石油类含量为0.003~0.066mg/L,平均含量为0.015mg/L,平均污染指数为0.30,保护区水体中的石油类基本符合一类海水水质标准。保护区表层沉积物中石油类含量为3.0~54.8mg/kg,平均值为11.109mg/kg,符合海洋沉积物第一类质量标准。保护区水体和沉积物中石油类含量的变化规律基本相似,但是沉积物中石油类含量的变化更大。根据调查数据分析,保护区水体中石油类的主要来源是保护区社区小型渔船航行排放的石油类,以及保护区周边渔船在航行过程排放的石油类扩散到保护区海域。     

南麂列岛自然保护区海域红色裸甲藻赤潮及其成因分析

2002年9月16～19日南麂列岛海域发生3km2 红褐色赤潮 ,其原因种为红色裸甲藻(GymnodiniumsanguineumHirasaka) ,密度高达4.6×105 个/L。赤潮发生时伴随细菌的大量繁殖 ,江浙沿岸流所携带的营养物质是本次赤潮发生的基础 ,森拉克台风是本次赤潮的重要诱因。南麂海域的赤潮多发季节为4～5月份 ,9～11月份发生赤潮的可能性也较大 ,大沙岙、马祖岙和火岙等水体交换相对较弱的岙口为赤潮多发区。为保护南麂列岛国家级海洋自然保护区珍稀海洋贝藻资源 ,需协调好保护和开发之间日益尖锐的矛盾 ,控制养殖业的发展规模和游客的数量。     

黄海辐射沙洲沉积物地球化学特征及其环境意义

对黄海辐射沙洲烂沙洋水道区域的3个钻孔共81个沉积物样品进行了微量、常量元素分析和^14C测年分析．化学元素质量分数的变化与当时沉积环境的变化相对应。突发事件(如风暴潮)的发生不但在沉积物的岩性上有所体现,而且在微量元素质量分数的变化上也有很明显的体现。微量元素Zr可作为沉积能量变化的地化指示剂,潮汐通道北部的西太阳沙区域的沉积动力环境在4000a以前是较弱的。潮流通道的上段沉积物是来自水深较浅的区域,由于潮流和波浪的作用使其能够保持稳定的水深。     

中国卤虫早期胚胎发育相关基因的研究--mRNA差异显示技术的三种不同染色方法比较

利用mRNA差异显示技术研究中国孤雌生殖卤虫胚胎发育的相关基因，并对中国孤雌生殖卤虫差异显示中SYBR Green Ⅰ、硝酸银和溴化乙锭三种染色方法进行了比较。以三种单碱基锚定引物对发育0h，4h，8h，12h，16h和10天的中国孤雌生殖卤虫的RNA进行逆转录和26种随机引物进行PCR反应，经非变性的6％聚丙稀酰胺凝胶电泳后，分别用SYBR Green Ⅰ、硝酸银和溴化乙锭染色，最后进行差异条带的回收和再扩增。结果表明：(1)6种样本的DD-PCR产物显示长200-3．0k不等的扩增片段，条带清晰，并呈现出有无和强弱的变化(2)SYBR Green Ⅰ和硝酸银染色的灵敏度比溴化乙锭染色的灵敏度高(3)经SYBR Green Ⅰ和溴化乙锭染色的凝胶的回收和再扩增效率比硝酸银染色的高(4)水煮法和NAP-25过柱法对凝胶片段的回收效果几乎相当。利用mRNA差异显示技术研究中国孤雌生殖卤虫胚胎发育相关基因时，得到了较好的扩增片段；三种染色方法中SYBR Green Ⅰ染色灵敏度较高，并且SYBR Green Ⅰ染色有利于凝胶片段的回收和再扩增。     

不同养殖方式对皱纹盘鲍养殖效果及养殖水质的影响

在天津地区对2.2 cm左右规格的皱纹盘鲍(Haliotis discus hannai)进行试养殖,比较了两种养殖模式(笼养与砖养)、两种养殖密度下鲍的存活与生长情况,以及不同换水频率和不同饲料形状对鲍的生理状态和养殖水质的影响。结果表明:试养殖1个月后,笼养下的鲍存活率(74.4%)低于砖养(84.0%),且低密度养殖下鲍的存活率更高;随着换水频率的增加,鲍的摄食量逐渐增加,养殖水体中氨氮、亚硝酸氮、硝酸氮、化学需氧量的含量均呈减少的趋势;投喂不同形状饲料的组别间养殖水体氨氮、亚硝酸氮含量差异显著。因此,砖养模式更适合于作为天津地区鲍养殖的模式,并且降低密度、提高换水频率有助于改善水质,改良鲍的摄食、存活状况。