青藏高原柴达木盆地尕海盐湖浮游生物群落多样性特征的初步研究

青海尕海是青藏高原柴达木盆地比较典型的高盐度且具有丰富卤虫资源的盐湖 ,海拔高程 2 849.6m。 1997年夏季我们对尕海盐湖浮游生物主要类群群落多样性特征进行了初步调查。调查期间在内湖主要水体 5个断面2 2个采样站共发现浮游藻类 46种 ,平均密度为 5 4.39× 10 4 Cells/L ;浮游动物 12种 ,全湖平均密度为 8.2 2个 /L ,平均生物量 0 .2 9mg/L。通过盐度含量较高 (119g/L)的内湖主要水体采样断面与盐度含量较低 (1.8g/L)的湖西北岸小水面采样断面比较 ,浮游生物不论是在种类组成特征、群落的多样性还是其个体丰度都存在十分明显的差异。结果表明 :在盐湖生态系统中 ,盐度是决定生物物种多样性及其个体丰度的关键因素之一。

温度对青海尕海盐湖卤虫发育和种群增长的影响

1990～ 1999年对尕海卤虫的温度特性研究表明 ,无节幼虫的耐寒力比幼虫期高 - 1 7℃ ,比成虫期高- 0 9℃ ,即无节幼虫的耐寒力最强 ,幼虫对低温最敏感 ;孵化发育起始温度 9 94℃ ,幼虫发育起始温度10 33℃ ,有效积温 (℃·d)前者为 2 2 91± 2 0 8,后者为 2 6 1 2 6± 2 4 1,平均世代发育起点温度 10 2 8℃ ,有效积温 45 8 6 8± 5 7 6 0 ;依据生命表计算得出的各项生态学参数与温度存在显著的函数关系 ,其适温范围基本介于 10℃～ 39℃ ,最适温度介于 2 4 9℃～ 30 5℃ ,种群增长倍数 >2的温度范围在 15℃～ 34℃ ;依据 1993～ 1994和 1997年尕海水域温度测定资料 ,结合上述实验结果 ,得出该卤虫的年世代数为 2 6 7± 0 34个代 ,一年中有4 6 9± 0 43个生殖高峰期 ;最后一个完整世代的起始时间是 8月 10日 ;因积温不足 ,在 9月 1日以后出现的无节幼虫将不能完成到成虫期的发育 ;在 7月中旬至 9月中旬是种群生产力高峰期 ,在此期间种群的加倍时间 <30d ,内禀增长率 >0 0 2d-1,开发潜力最大。

青海尕海盐湖初级生产力特点

１９９７ 年夏季对青海尕海盐湖的生态系统进行了初步研究． 初级生产力研究结果表明：（１） 水域毛初级产氧量平均值为３ ．２７３ｇ ｍ －２ｄ－１ ，其中底栖藻类占７０．９９％ ，底栖藻类单位面积毛初级生产力是浮游植物的２．４５倍．（２） 水域初级生产力构成格局为：由沿岸到湖心区，随着水深的逐步增大，底栖藻类初级生产力逐步减少，浮游植物初级生产力逐渐占主导地位． 前者所占的比例在０．５５ ｍ 水深时为９７．７２ ％ ，在大于１３．０ ｍ 水深后即降至０．０ ％ ．（３）与国际有关文献相比。

青海省盐湖卤虫资源的开发与保护——以尕海湖为例

通过在青海省的实地考察和对尕海湖周边植被的调查,总结出造成青海省尕海湖卤虫产量减少的影响因素,得出防治对策,并对若干卤虫开发利用的问题进行了讨论,为青海省卤虫资源的保护与开发提供参考。

Some ecological parameters of Artemia parthenogenetica Gahai and their use in resource exploitation

The effects of temperature on population characteristics of Artemia parthenogenetica Gahai from the Gahai Salt Lake,Qinghai Province,China,were studied in the laboratory at a salinity of 60‰.The major conclusions are as follows:(1)It was found that the adaptive temperature for the development of brine shrimp ranged from 10℃to 39℃.The threshold temperature of development(TD)and the effective accumulative temperature(TA)for hatching were 9.94℃·d and(22.91
2.08)℃·d,respectively.The TD and TA for the larva were 10.33℃·d and(261.26
24.1)℃·d,respectively,and for the whole generation were 10.28℃and(458.68
57.60)℃·d,respectively.(2)It showed that the population’s net reproduction rate(R_(o)),the intrinsic rate of natural increase(r_(m)),the mean generation time(T),the finite rate of increase(λ),and the days for population to double(t)of the brine shrimp were determined over temperatures ranging from 19℃to 34℃by analyzing the life table and numerical model.In the temperature range of 14.3℃to 37.3℃for R_(o)>1,the optimum temperature(℃)for R_(o),rm,λ,and t were 25.8℃,29.8℃,30.5℃,and 29.02℃,respectively.The maximum values of R_(o),r_(m) andλwere 54.86 ind.,0.106138/d,and 1.1070/d,respectively.The minimum value of t was 4.73 d.The value of T was in a range of 96.77 to 16.10 d.(3)Based on the 1993-1994 and 1997 data of the water temperature in the Gahai Salt Lake,Qinghai Province,it was estimated that the number of generation of A.parthenogenetica Gahai and the number of the reproductive peak value were 2.67
0.34 and 4.69
0.43 in a year,respectively.The peak of nauplii of the first generation was on April 20 to 28.The last whole generation began on August 10.The first reproductive peak was on June 18 to 25.The last reproductive peak was on September 12 to 17.The nauplii that hatched after September 1 cannot complete the development from nauplii to adults because of insufficient habitat effective accumulative temperature.During the period from July 11 to September 20,there was a relatively high productivity of the population.In this case,doubling the population would take less than 30 d,and the intrinsic rate of natural increase was over 0.02/d.Therefore,the value of resource exploitation would be maximal during that period annually.

尕海

尕海,亦称巴尕哈日诺尔,蒙语音译,意为"小黑湖",位于青藏高原东北部柴达木盆地东北隅,青海省海西蒙古族自治州德令哈市东南部25 km[1]。它是地处高原内陆咸水湖泊,海拔2,849 m。尕海地理位置为37°05′58″N-37°10′00″N,97°31′05″E-97°35′47″E,中心点位置为37°07′30″N,97°33′03″E(图1-2)。