长江中华鲟栖息地适合度模型研究

对与水生生物生存栖息相关的河流底质、水深、水温、流速、水质等生态因子进行研究。提出水生生物的栖息地适合度模型,从生物生存栖息地影响角度对河流治理工程进行科学的评价。以长江珍稀动物中华鲟为研究对象,通过对影响中华鲟的各种生态因子的统计研究,分析整理出适宜其生存繁殖的河流水温、水深、底质、流速、含沙量及食卵鱼10个因子的临界指标,得出了这些因素的适合度曲线。发展了适合评价长江中华鲟栖息地的适合度方程,并用12组实测数据对模型进行了修改验证,提出了适合评价长江中华鲟栖息地适合度模型。     

2000-2002年，从德克萨斯州奥斯丁地区Barton泉域系统排出沉积物的质量

Barton泉域系统的4个出水口为Barton泉火蜥蜴（联邦政府列出的一种即将绝种的物种）提供了唯一的栖息地。大雨过后沉积物被冲刷，并流入爱德华兹含水层的Barton泉，因而常常使泉水变得混浊。     

漫步临海行走括苍

漫步临海,怎么也绕不过括苍。 括苍是一座山名,一座历史上赫赫有名的道家仙山。原名真隐山,山名因陶弘景而取。史载南朝梁时道教思想家、医药学家、炼丹家、文学家,人称“山中宰相”的陶弘景曾隐居此山。“真”即真人、仙人,“隐”指陶弘景的自号“华阳隐居”。现在山上的“灯坛观”就是他的栖息地遗址。     

Combination of ecoprofile and least-cost model for eco-network planning

The protecting requirements and functional connectivity of species in isolated habitat patches are crucial factors of eco-network planning.This study aimed to improve the method of eco-network planning for species conservation.Ecoprofiling was used to group the species by similar behavior types,namely,choice of ecosystem,area requirement,and short distance dispersal abilities.A least-cost model was used to simulate the optimal corridor location to maintain functional connectivity.A combination of ecoprofile and least-cost model was hired to develop an eco-network that promoted species conservation.A case study was also conducted in Bei-jing,China.In addition to the required ecosystem,habitat area is an important parameter for habitat extraction.Habitat area can remove noise habitat patches because of lacking area.Short-distance dispersal can be used to identify corridor requirements and avoid unneces-sary building requirements.Species with various dispersal abilities exhibit significant differences in terms of corridor length and loca-tion requirement.Habitat isolation is the main threat for weakly mobile species,and habitat loss is the major risk of mobile species pro-tection.Different species groups also exhibit distinct landscape pattern demands for an eco-network,and the eco-network planning based on specific species can not protect other species.We proposed that a combination of ecoprofile and least-cost model improved the efficiency of species conservation by eco-network planning.     

栖息地分布与种内竞争对刺参集群特征的影响

为探究刺参(Apostichopusjaponicus)种内竞争与栖息地对其群体分布的影响,作者通过缩时摄像机拍摄及视频分析,研究了刺参集群分布特征,结果发现:刺参在礁石栖息地的栖息时间显著高于在缸壁处的栖息时间(P 0.05),刺参对栖息地有明显偏好性;刺参在运动时并未聚集在同一栖息地,而离散分布在多处栖息地中(P 0.05);当密度增大到15头/缸(11.31头/m~2, d=1.3 m)时,刺参在栖息地内的平均聚集率和平均聚集时间比例会显著下降(P 0.05),种内竞争加剧,刺参多呈斑块状分布,在密度过高时种内竞争压力上升,刺参个体间选择分散以减少竞争。本研究查明了实验室条件下栖息地分布和种内竞争对刺参集群特征的影响,可为野外刺参增养殖与资源持续利用提供理论参考。     

海州湾及邻近海域口虾蛄栖息地适宜性建模的环境变量优化

Habitat suitability index(HSI) models have been widely used to analyze the relationship between species abundance and environmental factors, and ultimately inform management of marine species. The response of species abundance to each environmental variable is different and habitat requirements may change over life history stages and seasons. Therefore, it is necessary to determine the optimal combination of environmental variables in HSI modelling. In this study, generalized additive models(GAMs) were used to determine which environmental variables to be included in the HSI models. Significant variables were retained and weighted in the HSI model according to their relative contribution(%) to the total deviation explained by the boosted regression tree(BRT). The HSI models were applied to evaluate the habitat suitability of mantis shrimp Oratosquilla oratoria in the Haizhou Bay and adjacent areas in 2011 and 2013–2017. Ontogenetic and seasonal variations in HSI models of mantis shrimp were also examined. Among the four models(non-optimized model, BRT informed HSI model,GAM informed HSI model, and both BRT and GAM informed HSI model), both BRT and GAM informed HSI model showed the best performance. Four environmental variables(bottom temperature, depth, distance offshore and sediment type) were selected in the HSI models for four groups(spring-juvenile, spring-adult, falljuvenile and fall-adult) of mantis shrimp. The distribution of habitat suitability showed similar patterns between juveniles and adults, but obvious seasonal variations were observed. This study suggests that the process of optimizing environmental variables in HSI models improves the performance of HSI models, and this optimization strategy could be extended to other marine organisms to enhance the understanding of the habitat suitability of target species.     

Phenotypic plasticity in Bacillus cereus strains isolated from various Antarctic habitats

We studied five strains of psychrotolerant Bacillus cereus （B. cereus） isolated from Antarctic snow （BCsn）, ice （BCic）, lake water （BCwt）, sediment （BCsd）, and soil （BCsl） samples in terms of their growth, biochemical properties, and heat shock re- sponses. Analyses of growth kinetics at 4℃ showed that BCsn had the fastest generation time （16.1 h）, whereas BCWT had the slowest （30.8 h）. Strain BCsd formed the largest zone of lipid hydrolysis （18 mm） whereas BCsn formed the smallest zone （3 mm）.Only BCsd produced gelatinase. These physiological differences illustrate adaptations of B. cereus isolates to different niches. Strains BCsl and BCwr were resistant to all 12 of the antibiotics tested. Strains BCsn, BCio, and BCsd were resistant to cell wall synthesis inhibitors （penicillin and ampicillin） and susceptible to protein synthesis inhibitors （tetracycline and streptomycin）. A carbon-substrate utilization assay revealed that BCsn, BCic and BCwr could specifically utilize D-glucose-6-phosphate, salicin, and 2＇-deoxyadenosine, respectively, indicating a degree of metabolic diversity among these Antarctic B. cereus strains. An analy- sis of heat shock proteins （HSPs） produced in response to a 60℃ heat treatment revealed significant variations in the amounts of HSP33 （p = 0.01, df= 4）, HSP44 （p = 0.003, dr= 4）, and HSP60 （p = 0.04, df= 4） among the strains. This emphasizes the impor- tance of HSPs in bacterial taxonomy. These results show that there are considerable adaptive variations among B. cereus strains from extremophilie environments. This could be significant in evaluating the taxonomy and evolution of this species.     

鸟类栖息地营建研究与实践——以天津大黄堡湿地自然保护区为例

湿地自然保护区是重要的鸟类栖息地。以天津市大黄堡湿地自然保护区为研究对象,从水系修复、植被修复、鸟类生境营建3个方面开展基于营建鸟类栖息地的湿地保护与修复治理工程,提出水系连通工程、水污染防治工程、核心净水措施、植被生境营造、生态廊道营建、特种鸟类适宜生境营造措施。目前保护区核心区恢复建设已完成,大幅优化了鸟类栖息环境。本研究对我国基于鸟类栖息地营建的湿地自然保护区规划设计研究及实践提供借鉴与参考。     

基于栖息地指数的西北太平洋日本鲭渔情预报模型构建

根据2014−2017年5−11月西北太平洋公海灯光围网日本鲭(Scomber japonicus)生产数据,结合同期的环境遥感数据,分别基于捕捞量和作业次数,构建日本鲭栖息地适宜性指数(Habitat Suitability Index,HSI)模型。选取海表水温、海面高度异常和叶绿素a浓度,采用一元指数回归拟合,建立各个环境变量的适应性指数模型,并利用线性规划方法确定各环境因子的权重,从而提高日本鲭HSI模型对渔场的预报精度。利用2018年5−11月的实际捕捞数据对模型进行预报准确率验证,在基于渔获量和作业次数构建的HSI模型中,HSI大于0.7的海域,渔获量平均占比分别为77.29%、76.79%,这表明基于不同权重环境因子的HSI模型能够较好地预测西北太平洋公海日本鲭中心渔场。     

蓝色新事

<正>1巴哈马群岛动物Animal罕见上万条北梭鱼交配产卵漩涡近日在巴哈马群岛浅水区发现了10000条鱼旋转形成的龙卷风。这其实是北梭鱼产卵前的行为,研究人员利用电子标签追踪了10000条处于产卵周期末期的北梭鱼,并将这种神秘行为的观察以视频的形式展示给巴哈马群岛环境部,以及保护合作者巴哈马群岛国民信托组织和大自然保护协会。每年,这种北梭鱼能够为娱乐水产捕捞业创造上亿美元的收入,但它因栖息地的丢失以及拖网作业方式的过度捕捞而面临威胁。这项发现指出了在保护计划里同时考虑深水和浅水栖息地的必要性。