模拟增雨对巴里坤湖干涸湖底沉积物CO2通量的影响

明确湖泊沉积物碳过程对气候变化的响应,是全面了解湖泊生态系统碳收支的重要环节.为探究未来降雨增加对沉积物碳通量的影响,本研究以新疆哈密巴里坤盐湖干涸湖底原状沉积物为对象,基于1960年以来新疆哈密地区降雨量增加速率(4mm.10a-1)以及植物生长季多年降雨量分布特征,以2016年生长季(5-10月)降雨量(86 mm...     

感受阿拉善（一）——来自干湖底的视角

这是一个吸引我们非要走进去看个究竟的地方。现在它就在我们脚下了——已经干涸了近半个世纪的西居延海的海底。如今它是沙尘暴,准确地说是尘暴的一个重要策源地。数千里之外的许多角落,包括我们队伍中每个人的居住地都曾接纳过来自这里的粉尘,被它的尘埃遮天蔽日。然而,它究竟是什么样子？肆虐了近半个世纪之后又是怎样？那里的人们是怎样过来的,现在又如何？     

华北落叶松的组织培养再生植株

TissneCultureandPlantletRegenerationofLarixprincipis－rupprechtiiQILi-wang,HANSu－Ying,YANGYun－Long,ZHANGYun－Xiang（DepartmentofForestry,ShanxiAgriclturalUniversity,Taigu030801）1植物名称华北落叶松（Larixprincipis-rup-prechtii）。2材料类别19年树龄植株上当年生嫩茎段。3培养条件培养基：（1）MS＋6－BA0.2mg／L（单位下同）＋NAA0．2＋IBA0．1;（2）SH＋6－BA0．5＋NAA1＋IBA0.5;（3）WPM（大量）＋MS（微量）＋6－BA0．3＋KT0．8＋NAA1＋2．4－D0．2;（4）WFM（大量）＋MS（微…     

山西关帝山华北落叶松林的生物量

华北落叶松(Larix principis—rupprechtii)林是山西典型的寒温性针叶林之一,主要分布于关帝山、管涔山等海拔1600—2800m 的阴坡及半阴坡。我们于1988年5—6月对山西关帝山的华北落叶松林的生物量进行了研究。1.植被地理环境与群落特征关帝山位于吕梁山脉中段,约当37°20′—38°20′N,110°     

华北落叶松一年生茎的电子显微镜研究

运用透射电子显微镜技术研究华北落叶松一年生枝条组织细胞的超微结构。皮层及韧皮部由大量薄壁细胞及少量筛胞组成。薄壁细胞中的前质体有分裂行为,叶绿体中含有体积大的淀粉粒及明显的基粒片层结构;有“Ｖ”形线粒体琢链条状粗糙内质网,液泡多以次生溶酶体状态存在。     

华北落叶松生态适应性的定量分析与评价

本文根据华北落叶松分布和生产力的变化规律,确定了其气候生态指标和效值。根据生态因子间相互作用规律原理,提出了分析与评价华北落叶松生态适应性的数量化指标体系,包括热量指数ＧＴＩ,水分指数ＧＭＩ,水热指数ＧＭＴＩ。这一指标体系能够定量评价华北落叶松的生态适应性。本文应用水热指数ＧＭＴＩ对其天然分布区生态适应性等级作了定量划分,结果与实际情况相符。     

华北蹄盖蕨的引种栽培研究

华北蹄盖蕨(ＡｔｈｙｒｉｕｍｐａｃｈｙｐｈｌｅｂｉｕｍＵ.Ｃｈｒ.)是我国北方常见的蕨类植物,野生资源极为丰富。本种株型丰满、叶端微垂,叶色青翠或叶轴玫瑰紫色,夏秋间由白变红褐色的马蹄形孢子囊群布满叶片背面,具有较高观赏价值。为此,我们自1994年起,在进行野生观...     

华北落叶松树干主要营养元素的空间分布

用标准地－标准木－分层分割法测定了华北落叶松（Ｌａｒｉｘ ｐｒｉｎｃｉｐｉｓ－ｒｕｐｐｒｅｃｈｔｉｉ Ｍａｙｒ）树干主要营养元素的分布规律,结果为：树干木质部水平方向Ｎ、Ｐ、Ｋ质量分数随年龄增加逐渐增大,Ｃａ、Ｍｇ的逐渐减少。树干木质部垂直方向Ｎ、Ｐ、Ｋ质量分数随圆盘高度增加而增加,Ｃａ、Ｍｇ变化较小。树皮Ｎ、Ｐ、Ｋ、Ｍｇ质量分数随圆盘高度的增加而增大,Ｃａ有减小的趋势,但梢部质量分数较高;树干主要营养元素的质量分数大小排序为：Ｋ〉Ｃａ〉Ｎ〉Ｍｇ〉Ｐ。不同个体不同组分质量分数之比分别为,皮／木 Ｎ：４．１～６．３,Ｐ：２．８～４．８,Ｋ：２．１～２．７,Ｃａ：２．３～４．１,Ｍｇ：２．１～３．１;皮／心,Ｎ：４．９～８．６,Ｐ：５．２～７．５,Ｋ：２．２～２．７,Ｃａ：２．６～３．８,Ｍｇ：２．０～３．２;边／     

华北蓝盆花的组织培养与植株再生

以华北蓝盆花（Scabiosa tschiliensis）无菌苗的叶片及叶柄为外植体,建立了华北蓝盆花的无性繁殖体系。结果表明,叶片外植体为诱导不定芽的适宜外植体,其不定芽诱导的适宜培养基为MS＋4.0 mg.L–16-BA,不定芽生根的最适培养基为MS＋2.0 mg.L–1IBA,幼苗移栽成活率可达70%以上。     

华北晚更新世的石片石器

本文首先简要梳理了晚更新世华北地区石片石器发展历程;进而探讨石片石器与南邻的砾石工业,北部边疆地区新发现的莫斯特文化遗存,以及更晚来自西北方向的石叶/细石器技术的交流互动。在此基础上,重点讨论晚更新世华北石片石器与现代人在该地区出现与发展历程之间的关系,提出石片石器是华北地区旧石器文化发展的主流,亦是追溯该地区现代人出现与发展课题至关重要的考古学证据。     

Iron-Reducing Microbial Communities of the Lake Baikal Low-Temperature Bottom Sediments

Microbiology - Psychroactive enrichment cultures reducing anthraquinone 2,6-disulfonate (AQDS) and soluble complexes of ferric iron at 5–20°C were isolated from the samples of Lake...     

Aerobic Methanotrophic Communities in the Bottom Sediments of Lake Baikal

The results of the first systematical investigation into the aerobic methanotrophic communities inhabiting the bottom sediments of Lake Baikal have been reported. Use of the radioisotopic method revealed methane consumption in 12 10- to 50-cm-long sediment cores. The maximum methane consumption rates (495–737 µl/(dm³ day) were recorded in sediments in the regions of hydrothermal vents and oil and gas occurrence. Methane consumption was most active in the surface layers of the sediments (0–4 cm); it decreased with the sediment depth and became negligible or absent at depths below 20 cm. The number of methanotrophic bacteria usually ranged from 100 to 1000 cells/cm³ of sediment and reached 1 million cells/cm³ in the regions of oil and gas occurrence. The seventeen enrichment cultures obtained were represented mainly by morphotype II methanotrophs. Phylogenetic analysis of the enrichment cultures in terms of the amino acid sequence of the α subunit of the membrane-bound methane monooxygenase (MMO) revealed the predominance of methanotrophs of the genus Methylocystis. The results obtained suggest the presence of an active aerobic methanotrophic community in Lake Baikal.__________Translated from Mikrobiologiya, Vol. 74, No. 4, 2005, pp. 562–571.Original Russian Text Copyright © 2005 by Gainutdinova, Eshinimaev, Tsyrenzhapova, Dagurova, Suzina, Khmelenina, Namsaraev, Trotsenko.     

Bottom fauna and littoral vegetation fauna in Lake Maarsseveen

Summary The littoral vegetation starts its development only in June and reaches its highest expansion in autumn. By that time the organic debris from these plants starts to play an important role for detritivorous organisms. The quantitative development of the fauna in the littoral is highest in autumn and early winter. The bottom fauna in the hypolimnetic parts of the lake is less dependent of the season. The experiments with artificial plants have shown that most species are present when the littoral vegetation is absent. Owing to the absence of substrate in the form of vegetation with epiphyton as a major food resource the numbers in spring and early summer are low. The most productive invertebrate isDreissena polymorpha.     

“黑美人”土豆色素体外抗氧化性研究

采用普鲁士蓝法、DPPH清除体系、H2O2/Fe2+/水杨酸检测体系、亚硝基清除体系、卵黄脂蛋白不饱和脂肪酸(PUFA)过氧化体系、邻苯三酚自氧化法研究了黑美人土豆色素的体外抗氧化活性,并同VC进行了比较。结果表明,黑美人土豆色素对几种自由基均有不同的清除作用,其中黑美人土豆色素的还原力、抗脂质过氧化能力、清除羟基自由基、亚硝基、超氧阴离子自由基(O2-.)和DPPH自由基的能力均高于VC。该结果显示,黑美人土豆色素是一种较好的天然自由基清除剂,可以作为绿色食品用于人们的日常饮食,有较大的开发利用潜能。     

Structure and dynamics of the periphytic algae of Jinyang Lake in Shanxi Province, North China

The structure and dynamics of periphytic algae in Jinyang Lake, the largest man-made lake in Taiyuan, Shanxi, have been studied by examining the periphytic algae samples collected from four sampling stations, during March 2006 to February 2007. In total, 227 species of periphytic algae (including varieties), belonging to three divisions, 27 families, 62 genera, have been identified. Diatoms were the dominant periphytic algae group. Taken the Shannon–Weaver, Margalef and Simpson diversity index together, it showed obvious temporal and spatial dynamics among different seasons and different sampling stations. The highest periphytic community structure evenness appeared at sampling station I in spring, summer and autumn, while at sampling station III in winter. The average biomass of periphytic algae varied from seasons. Our data showed that major factors affecting the periphytic algae in Jinyang Lake was water temperature, nutrient levels as well as human activities. In addition, the main effect caused by thermal power plant has been discussed.     

Bacterial Processes of the Methane Cycle in Bottom Sediments of Lake Baikal

The activity of methanogenic and methanotrophic bacteria was evaluated in bottom sediments of Lake Baikal. Methane concentration in Baikal bottom sediments varied from 0.0053 to 81.7 ml/dm³. Bacterial methane was produced at rates of 0.0004–534.7 l CH₄/(dm³ day) and oxidized at rates of 0.005–1180 l CH₄/(dm³ day). Peak methane production and oxidation were observed in Frolikha Bay near a methane vent. Methane was emitted into water at rates of 49.2–4340 l CH₄/(m² day). Rates of bacterial methane oxidation in near-bottom water layers ranged from 0.002 to 1.78 l/(l day). Methanogens and methanotrophs were found to play an important role in the carbon cycle through all layers of sediments, particularly in the areas of methane vent and gas-hydrate occurrence.     

Structure and dynamics of the periphytic algae of Jinyang Lake in Shanxi Province, North China

The structure and dynamics of periphytic algae in Jinyang Lake, the largest man-made lake in Taiyuan, Shanxi, have been studied by examining the periphytic algae samples collected from four sampling stations, during March 2006 to February 2007. In total, 227 species of periphytic algae (including varieties), belonging to three divisions, 27 families, 62 genera, have been identified. Diatoms were the dominant periphytic algae group. Taken the Shannon–Weaver, Margalef and Simpson diversity index together, it showed obvious temporal and spatial dynamics among different seasons and different sampling stations. The highest periphytic community structure evenness appeared at sampling station I in spring, summer and autumn, while at sampling station III in winter. The average biomass of periphytic algae varied from seasons. Our data showed that major factors affecting the periphytic algae in Jinyang Lake was water temperature, nutrient levels as well as human activities. In addition, the main effect caused by thermal power plant has been discussed.