土壤盐分特征对内陆盐沼盐生植物群落的影响          下载免费PDF全文

崔乔  何彤慧  全晓塞  陈向全  何玉实 《盐湖研究》2021,29(1)

为研究内陆盐沼植物群落的分布对土壤盐分的响应特征,选取鄂尔多斯盐湖盐沼区作为研究区,筛选了肉质耐盐植物群落,苔草植物群落和禾草植物群落3类典型植物群落,开展了土壤含水量、pH、电导率以及Na_⁺,K_⁺,Mg2_⁺,Ca_{^{2 +}},Cl_^-、SO_4^2-、CO_3^2-和HCO_3^-的测定,分析了区内典型植物群落对土壤水盐因子的响应规律。探讨了3类植物群落之间土壤因子含量的差异性;采用相关性分析和CCA分析,评价了3类植物群落多样性及物种分布随土壤因子的变化规律。结果表明,区内3类植物群落中,土壤盐分含量表现为肉质耐盐植物群落最高,苔草植物群落最低,禾草植物群落居中;植物多样性与土壤中含量最高的Na_⁺和SO_4^2-的相关性最显著;植物分布同时受到土壤盐分、水分和pH的显著影响。研究结果可为鄂尔多斯盐湖区土壤盐渍化改良和植被恢复提供理论支撑。  相似文献   

Effects of iron electrovalence and species on growth and astaxanthin production of Haematococcus pluvialis   总被引：1，自引：1，他引：0  

蔡明刚  李哲  齐安翔 《中国海洋湖沼学报》2009,27(2):370-375

To increase the cell concentration and the accumulation of astaxanthin in the cultivation of Haematococcus pluvialis, effects of different iron electrovalencies (Fe²⁺-EDTA and Fe³⁺-EDTA) and species (Fe-EDTA, Fe(OH)_x^32x and FeC₆H₅O₇) addition on cell growth and accumulation of astaxanthin were studied. Results show that different iron electrovalencies have various effects on cell growth and astaxanthin accumulation of H. pluvialis. Compared with Fe³⁺-EDTA, Fe²⁺-EDTA stimulate more effectively the formation of astaxanthin. The maximum astaxanthin content (30.70 mg/g biomass cell) was obtained under conditions of 18 μmol/L Fe²⁺-EDTA, despite the lower cell density (2.3×10⁵ cell/ml) in such condition. Fe³⁺-EDTA is more effective than Fe²⁺-EDTA in improving the cell growth. Especially, the maximal steady-state cell density, 2.9×10⁵ cell/ml was obtained at 18 μmol/L Fe³⁺-EDTA addition. On the other hand, all the various species of iron (EDTA-Fe, Fe(OH)_x^32x, FeC₆H₅O₇) are capable to improve the growth of the algae and astaxanthin production. Among the three iron species, FeC₆H₅O₇ performed the best. Under the condition of a higher concentration (36 μmol/L) of FeC₆H₅O₇, the cell density and astaxanthin production is 2 and 7 times higher than those of iron-limited group, respectively. The present study demonstrates that the effects of the stimulation with different iron species increased in the order of FeC₆H₅O₇, Fe(OH)_x^32x and EDTA-Fe. Supported by Xiamen Scientific and Technologic Projects (No. 3052Z20031086), Xiamen University Alumni Association Foundation in Singapore, and the First National College Students Innovative Experimental Project  相似文献   

First record of Paraonella platybranchia （Hartman, 1961） （Polychaeta： Paraonidae） from the Yellow Sea     

周进  李新正 《中国海洋湖沼学报》2009,27(1)

This paper reports for the first time a species of polychaetous family Paraonidae, Paraonella platybranchia (Hartman, 1961), a rare species found previously only in the coast near the boundary between the United States and Mexico, and it was recently discovered in the samples collected in 1982 from Chinese side of the Yellow Sea. This is the first record of the species in China as well as in the Northwest Pacific.  相似文献   

Length-weight relationships for six freshwater fish species in Iran   总被引：2，自引：0，他引：2  

M. S. HEYDARNEJAD 《中国海洋湖沼学报》2009,27(1):61-62

The aim of this study is to report the length-weight relationship parameters (a and b) for some economically important fish species from Iranian freshwaters. The length-weight relationships (LWR) are calculated for six freshwater fish species collected during 2006 and 2007 in Iran. The values of the exponent b in the LWR (W=aLb) vary between 2.985 and 3.543. The LWR with high correlation coefficient (r2) is significant for all the species. These parameters are of great importance to evaluate the relative condition of populations, biology, species management and their fisheries and stock assessment. The application of the length-weight relationships presented here should be limited to the observed length ranges.  相似文献   

全球海洋生物普查发现大量物种     

《海洋世界》2008,(12):5-5

第四次全球海洋生物普查近日完成。在最近的一年里，科学家发现了大约1000种新的海洋动植物，其中包括栖息地最深的生物—日本琉球海沟水下7224米的深海栉水母。在大西洋比斯开湾，科学家发现了约20厘米长的特大号牡蛎的壳。在美国路易斯安那州海岸附近，还有一种长约38厘米的未知软体动物。  相似文献   

巴丹吉林沙漠周边植被特征和物种多样性   总被引：1，自引：1，他引：0  

王蒙  董治宝  逯军峰  李继彦  罗万银  崔徐甲  张玉  刘铮瑶  焦原磊  杨林海 《中国沙漠》2015,35(5):1226-1233

通过对巴丹吉林沙漠周边地区的野外调查,以重要值为测度指标,计算物种多样性指数、均匀度指数和优势度指数,对巴丹吉林沙漠周边地区荒漠植物群落物种多样性进行分析。结果表明:(1)该区域共计植物37种,各区域重要值大于0.1的物种中,灌木和半灌木占优势;(2)8个区域的Shannon-Wiener指数、Simpson指数、丰富度指数和优势度指数差异显著,区域5(北部)和7(西部)因含有单物种群落,Shannon-Wiener指数和Simpson指数显著低于其他区域;(3)荒漠植物群落结构层次中,8个区域的灌木层片每个多样性指数均没有显著性差异,草本层片在8个区域中多样性水平差异显著,由于荒漠区植被物种稀少、数量少,灌木层和草本层并未表现出显著差异;(4)巴丹吉林沙漠物种多样性水平较低,生态系统脆弱,对巴丹吉林沙漠周边地区生态系统重建时应该关注各种生态型植被的恢复重建。  相似文献   

Distribution and fate of metals in the Montenegrin part of Lake Skadar     

Mirjana VEMIC  Diederik ROUSSEAU  Gijs DU LAING  Piet LENS 《国际泥沙研究》2014,29(3):357-367

Skadar Lake,the largest lake on the Balkan Peninsula,is famous for a wide range of endemic and rare,or even endangered plant and animal species.Different anthropogenic pressures have,however,influenced the fragile equilibria of the lake ecosystem,with metal pollution as one of the primary concerns.Therefore,this study investigated spatial distribution of metal pollutants in the water and sediment phase of Skadar Lake,and anthropogenic and environmental factors affecting this distribution.A sieving analysis showed that sediment in Skadar Lake is mainly distributed in the three smallest fractions（colloid,clay and silt）.Eleven metals were analyzed in the lake surface and bottom water,and only six of them were detected：potassium,magnesium,calcium,nickel,aluminum and manganese.They were all present at low concentrations.In contrast,sediments contained elevated levels of some metals with concentrations between 28.1-126.8 mg kg~（-1） for Ni,23.6-79.2 mg kg~（-1） for Cr,9.2-36.9 mg kg~（-1） for Cu,199-878 mg kg~（-1） for Mn and 9.6-23.1 g kg~（-1） for Fe.Nickel exceeded consensus-based guidelines for safety towards freshwater dwelling organisms.The organic matter content of the sediment fluctuated between 4.7 and 21.5%.No correlations were found between metal concentrations,organic matter and sediment particle size fractions,suggesting that the latter are not the main factors controlling metal accumulation in Skadar Lake.  相似文献   

警惕"绿色污染"     

翟峰 《南方国土资源》2004,(5):41-41

21世纪是绿色环保的世纪,21世纪的流行色是绿色。因为,随着国人绿色环保意识的提高,绿色逐渐进入人们的视野,开始成为公众关注的焦点。创造绿色已成为当今市场的最大卖点,并具前景广阔的商机。然而,我们在歌唱绿色、崇尚绿色之时,也要“一分为二”地辩证看待绿色问题,即要警惕因外来物种的入侵和人为造假的另类“绿色污染”——  相似文献   

荒漠植物群落物种多样性及其测度指标比较   总被引：11，自引：3，他引：8  

晋瑜  潘存德  王梅  万猛 《干旱区地理》2005,28(1):113-119

多样性指数及其测度指标的选择是群落多样性测度研究的基础,选择反映群落物种多样性、丰富度、优势度和均匀度的10种测定指数,分别以多度、盖度和重要值为测度指标,对克拉玛依农业综合开发区外围荒漠植物群落的物种多样性进行了定量测定,并对所选择的多样性指数进行了相关性分析和主成分分析。分析结果表明：对于荒漠植物群落,以重要值为测度指标的群落物种多样性、丰富度、优势度、均匀度测定结果比以多度和盖度为测度指标的测定结果更为合理;在多样性测定指数中,Shannon-Wiener多样性指数反映的群落多样性更为合理;荒漠植物群落的均匀度指数与多样性指数的相关性比丰富度指数与多样性指数的相关性高,说明物种组成相对稀少的荒漠植物群落其物种多样指数的高低主要取决于物种在群落中的均匀度。  相似文献   

Biomass allocation patterns of alpine grassland species and functional groups along a precipitation gradient on the Northern Tibetan Plateau   总被引：1，自引：1，他引：0  

Jian-shuang Wu  Zhen-xi Shen  Xian-zhou Zhang  Pei-li Shi 《山地科学学报》2013,10(6):1097-1108

Variations in the fractions of biomass allocated to functional components are widely considered as plant responses to resource availability for grassland plants. Observations indicated shoots isometrically relates to roots at the community level but allometrically at the species level in Tibetan alpine grasslands. These differences may result from the specific complementarity of functional groups between functional components, such as leaf, root, stem and reproductive organ. To test the component complementary responses to regional moisture variation, we conducted a multi-site transect survey to measure plant individual size and component biomass fractions of common species belonging to the functional groups： forbs, grasses, legumes and sedges on the Northern Tibetan Plateau in peak growing season in 2010. Along the mean annual precipitation （MAP） gradient, we sampled 7o species, in which 2o are in alpine meadows, 20 in alpine steppes, 15 in alpine desert-steppes and 15 in alpine deserts, respectively. Our results showed that the size of alpine plants is small with individual biomass mostly lower than 1.0 g. Plants keep relative conservative component individual responses moisture functional fractions across alpine grasslands at the level. However, the complementary between functional components to variations specifically differ among groups. These results indicate that functional group diversity may be an effective tool for scaling biomass allocation patterns from individual up to community level. Therefore, it is necessary andvaluable to perform intensive and systematic studies on identification and differentiation the influences of compositional changes in functional groups on ecosystem primary services and processes.  相似文献