白沙蒿种子萌发特性的研究Ⅰ．粘液瘦果的结构和功能

白莎蒿（Ａrtemisia sphaerocephala Krasch.)是中国西北部沙漠的流动及固定沙丘上广泛分布的优势种灌木。瘦果小而轻,借助显微镜和扫描电镜对瘦果的形态结果进行了观察,其种子的种质与果皮愈合,要皮外层为很厚的粘液层,其粘液层在遇湿后迅速吸水膨胀,其重量增至原来的５８９倍。在自然生境中,粘液物质将沙粒粘附于瘦果的使瘦果的重量发生变化。瘦果能长时间在水上漂浮,粘液物质有助于种子的萌发和苗的发育。白沙蒿产生三种不同颜色的瘦果,其种子具有不同的萌发速率但最终达到相的萌发率。研究表明：瘦果的粘液物质对白沙蒿种子的传播与萌发具有重要的生态意义。     

不同环境条件下沙生植物的CO2气体交换研究

对腾格里沙坡头地区两种沙生植物：油蒿（ＡｒｔｅｍｉｓｉｓａｏｒｄｏｓｉｃａＫｒａｓｃｈ．）和柠条（ＣａｒａｇａｎａｋｏｒｓｈｉｎｓｋｉｉＫｏｍ）。在旱季和雨季时ＣＯ２气体交换特点及其动态变化进行了研究,结果表明：在干旱条件下,油蒿（Ａ）和柠条（Ｃ）的光合作用均受到严重影响,其光合率率日变化日出后（７：００－９：ａ．ｍ．）有一较小高峰外,基本处于很低水平。降水后,Ａ和Ｃ的光合作用均明显提高,但Ｐｎ     

沙坡头人工固沙区的种子库动态

沙坡头人工固沙区的土壤种子库中共有４６种植物的种子,属于１７个科。其中菊科植物最多,达１１种;其次为藜科,７种;禾本科７种;豆科４种。既是现有植被组分种,其种子又存在于种子库中的,占总种数的３３．３％ 。油蒿（Ａｒｔｅｍ ｉｓｉａ ｏｒｄｏｓｉｃａ）、花棒（Ｈｅｄｙｓａｒｕｍ ｓｃｏｐａｒｉｕｍ ）和柠条（Ｃａｒａｇａｎａ ｋｏｒｓｈｉｎｓｋｉｉ）的种子产量为５４５±６７６．７３粒／ｍ ２、６．６７±１３．７４粒／ｍ ２、０．０３２±２．４３×１０－ ３粒／ｍ ２。油蒿在植株上成熟时不受虫害,而花棒、柠条的种子受害比例分别为３１．９２％ 和８３．２９％ 。在最适埋藏深度下,油蒿、柠条、花棒种子的累积发芽率分别可达７８．３％ 、８５．０％ 和６６．７％ ;萌发速度：油蒿＞ 柠条＞ 花棒。根据种子库动态分析和植被调查结果可初步预测：沙坡头人工固沙植被的演替趋向将是灌木以油蒿为主,草本以雾冰藜（Ｂａｓｓｉａ ｄａｓｙｐｈｙｌｌａ）、小画眉草（Ｅｒａｇｒｏｓｔｉｓｐｏａｅｏｉｄｅｓ）为主的群落     

油蒿(Artemisia ordosica)的化感作用研究

通过对鄂尔多斯高原毛乌素沙地油蒿（Ａｒｔｅｍｉｓｉａ ｏｒｄｏｓｉｃａ）化感作用研究,发现油蒿茎叶的水浸提液对几种受体植物种子的萌发率,幼苗长和根长生长均有不同程度的抑制作用,随水浸提液浓度的增加抑制作用逐步增加;用油蒿茎叶水浸提液进行盆栽试验,受体植物的出苗率,苗高,根长和干物重也受到抑制,苗的形态也与对照有较明显的差异;     

中国东北蒿属龙蒿组植物核型研究

报道了东北蒿属龙蒿组１０个各植物的核型。核型公式分别为：龙蒿（Ａｒｔｅｍｉｓｉａ ｄｒａｃｕｎｃｕｌｕｓ．Ｌ．）（２ｎ）＝４ｘ＝３６＝２８ｍ＋８ｓｍ;猪毛蒿（Ａ．ｓｃｏｐａｒｉａ Ｗａｌｄｓｔ．ｅｔ Ｋｉｔ．（２ｎ）＝２ｘ＝１６＝１２ｍ＋４ｓｍ;盐蒿（Ａ．ｈａｌｏｄｅｎｄｒｏｎ Ｔｕｒｃｚ．ｅｘ Ｂｅｓｓ．）（２ｎ）＝４ｘ＝３６＝３０ｍ＋４ｓｍ＋２ｓｔ;光沙蒿（Ａ．ｏｘｙｃｅｐｈａｌａ Ｋｉｔａｇ     

油蒿草场的保护与改良

油蒿草场的保护与改良王庆锁,陈仲薪史振英（中国科学院植物研究所生态室北京１０００４４）（河北省塞罕坝机械林场０６８４００）ＣｏｎｓｅｒｖａｔｉｏｎａｎｄＡｍｅｌｉｏｒａｔｉｏｎｏｆＡｒｔｅｍｉｓｉａｏｒｄｏｓｉｃａＲａｎｇｅｌａｎｄ．￥ＷａｎｇＱｉｎ...     

蒿属植物的染色体数目和核型研究（一）

本文报道了我国蒿属６种的染色体核型,它们的核型公式分别为：牡蒿（ＡｒｔｅｍｉｓｉａｊａｐｏｎｉｃａＴｈｕｎｂ．）２ｎ＝１８＝１２ｍ＋６ｓｍ（２ＳＡＴ）;西南牡蒿（Ａ．ｐａｒｖｉｆｌｏｒａＢｕｃｂ．－Ｈａｍ．ｅｘＲｏｘｂ．）２ｎ＝３６＝３０ｍ＋４ｓｍ＋２ｓｔ（６ＳＡＴ）;多花蒿（Ａ．ｍｙｒｉａｎｔｈａＷａｌｌ．ｅｘＢｅｓｓ．）２ｎ＝３６＝３０ｍ＋６ｓｍ：牛尾蒿（Ａ．ｄｕｂｉａＷａｌｌ．ｅｘＢｅｓｓ．）２ｎ＝３６＝２８ｍ＋８ｓｍ（２ＳＡＴ）;野艾蒿（Ａ．ｌａｖａｎｄｕｌａｅｆｏｌｉａＤＣ．）２ｎ＝５４＝４２ｍ＋１２ｓｍ;荚毛蒿（Ａ．ｖｅｌｕｔｉｎａＰａｍｐ．）２ｎ＝５４＝３６ｍ＋１８ｓｍ．     

脱落酸和抑制剂对萌发花生子叶肽链内切酶和花生球蛋白降解的影响

脱落酸（Ａｂｓｃｉｓｉｃａｃｉｄ,ＡＢＡ）抑制花生种子萌发的作用与核酸和蛋白质合成抑制剂的作用不同．ＡＢＡ（１００μｍｏｌ／Ｌ）在萌发零时施用,明显抑制肽链内切酶活性和同工酶表现以及花生球蛋白降解,萌发４８ｈ施用ＡＢＡ（１００μｍｏｌ／Ｌ）只降低肽链内切酶活性．ＡＢＡ的抑制作用不依赖于核酸和蛋白质合成．核酸合成抑制剂（３＇－脱氧腺苷,放线菌素Ｄ,５－氟尿嘧啶）和蛋白质合成抑制剂（亚胺环己酮）只能部分降低肽链内切酶活性,对肽链内切酶同工酶表现和花生球蛋白降解无明显影响．实验结果表明花生子叶肽链内酶不是在种子萌发过程中重新（ｄｅｎｏｖｏ）合成,文中讨论了肽链内切酶活性调节和花生贮藏蛋白降解的起始模式．     

白沙蒿种子萌发特性的研究 I. 粘液瘦果的结构和功能

白沙蒿(Artemisia sphaerocephala Krasch.)是中国西北部沙漠的流动及固定沙丘上广泛分布的优势种灌木。瘦果小而轻,借助显微镜和扫描电镜对瘦果的形态结构进行了观察,其种子的种皮与果皮愈合,果皮外层为很厚的粘液层,其粘液层在遇湿后迅速吸水膨胀,其重量增至原来的589倍。在自然生境中,粘液物质将沙粒粘附于瘦果的周围,使瘦果的重量发生变化。瘦果能长时间在水上漂浮,粘液物质有助于种子的萌发和苗的发育。白沙蒿产生三种不同颜色的瘦果,其种子具有不同的萌发速率但最终达到相同的萌发率。研究表明瘦果的粘液物质对白沙蒿种子的传播与萌发具有重要的生态意义。     

油蒿挥发油的化感作用研究

对毛乌素沙地油蒿挥发油的化感作用（Ａｌｅｌｏｐａｔｈｙ）及其化学成分进行了研究。结果表明：油蒿挥发油对苋、诸葛菜、萝卜种子萌发和幼苗生长具有不同程度的抑制作用;对小麦种子萌发几乎无影响,但对其幼芽和幼根的生长具一定影响。抑制作用最强的是对苋种子,挥发油组最终萌发率１８％,比对照组减少７１％,对其幼芽和幼根的生长影响也很明显。用ＧＣ、ＧＣ－ＭＳ－ＤＳ联用方法,共鉴定４３个化合物,其中相对百分含量在１．５％以上的化合物有如下１４种：１）α－蒎烯（α－ｐｉｎｅｎｅ）,２）桧烯（Ｓａｂｉｎｅｎｅ）,３）β－蒎烯（β－ｐｉｎｅｎｅ）,４）月桂烯（Ｍｙｒｃｅｎｅ）,５）对伞花烃（ρ－ｃｙｍｅｎｅ）,６）柠檬烯（Ｌｉｍｏｎｅｎｅ）,７）β－水芹烯（β－ｐｈｅｌａｎ－ｄｒｅｎｅ）,８）β－顺式罗勒烯（β－ｃｉｓ－ｏｃｉｍｅｎｅ）,９）β－反式罗勒烯（β－ｔｒａｎｓ－ｏｃｉｍｅｎｅ）,１０）松油烯－４－醇（Ｔｅｒｐｉｎｅｎ－４－ｏｌ）,１１）α－姜黄烯（α－ｃｕｒｃｕｍｅｎｅ）,１２）茵陈炔（Ｃａｐｉｌｅｎｅ）,１３）橙花叔醇（Ｎｅｒｏｌｉｄｏｌ）,１４）匙叶桉油烯醇（Ｓｐａｔｈｕｌｅｎｏｌ）。     

Comparison of Germination Strategies of Artemisia ordosica with Its Two Congeners from Deserts of China and Israel

Artemisia ordosica Krasch. is a dominant shrub occurring mainly on stable sand dunes in the Gobi Desert of China, in the Mongolian phytogeographic region. Achenes of A. ordosica germinate in light but poorly in dark and light is the limiting factor regulating the achene germination in sand depth. Achenes germinate in spring or autumn with an optimal temperature of 20 ℃. Achene mucilage can absorb large amounts of water and has important ecological function. Salt concentrations and sand moisture may regulate achene germination in sand. A. ordosica, A. sphaerocephala Krasch. and A. monosperma Delile. from different climates have similar responses to light, the underground location of achene, and sand moisture. Percentage of seedling emergence from different levels of sand depth is depends on the specific, temperature and intensity of light penetrating through the sand depths, as well as on sand moisture. The desert sand habitat seems to have had a dominant influence on the evolution of the germination strategies of these 3 Artemisia species.     

Total and speciation analyses of heavy metals in the sand fraction of Nigerian oil sands for human and ecological risk assessment

Total metal analysis and metal speciation of sand fraction of Nigerian oil sands were done to extract and partition heavy metals into six operationally defined fractions in order to assess environmental and health implications of the oil sand development. Soxhlet extraction of bitumen from the oil sand was done using toluene. Traces of water and extracting solvent were removed at 70°C from the sand fraction using oven. Elemental analysis was performed by Atomic Absorption Spectrophotometry. The heavy metals except Cu have low Pollution index values. Negative geo-accumulation index was obtained for the metals except Cu, indicating that the oil sands were uncontaminated with the metals. Strong and significant positive correlations existed between Fe/Pb, Zn/Cu, Cd/Pb, Ni/Cd, Ni/Pb, Cd/Fe, Ni/Fe and Cr/Zn, while strong and significant negative correlations existed between Mn/Pb and As/Mn, indicating common sources or chemical similarities and vice versa. T-test results indicated significant differences between the concentrations of the metals. Cross-plot analysis showed strong positive correlation between the sand fraction and Nigerian bitumen. Speciation analysis indicated highest and lowest indices of metal mobility for Zn and Pb, respectively. This study concluded that the sand fraction may not pose any environmental risks from elemental point of view.     

北方防沙带典型县域生态安全格局研究

生态安全格局构建是生态安全屏障建设和防风固沙能力提升的关键。北方防沙带是我国主要的风沙策源区，也是防治沙化的核心区，具有干燥少雨、植被稀疏、沙漠广布等生态特征，针对如何在北方防沙带构建适宜的生态安全格局做了研究探讨。以位于北方防沙带中部的民勤县为研究案例，基于“基质脆弱、廊道稀疏、斑块零碎”的景观基底和风沙源扩散机制，提出面向北方防沙带防风固沙能力提升的“控风源-堵风口-筑风廊-优网络”风沙阻隔型生态安全格局构建逻辑范式。结果表明该范式有助于深入了解北方防沙带生态安全问题与生态安全维持机制，可为其他干旱区生态安全格局构建提供新思路。     

Water purification using sand

Slow sand filters are used to purify drinking water. Each filter consists of a large tank containing a bed of sand through which water passes at typical rates of 0.1–0.3 m h^–1. Water is cleaned by physico–chemical and biological processes occurring at the air–water interface, within the bulk water, over the surface of the sand, and within the bed of sand. The processes found in sand filters replicate many of those found in natural sand banks and sandy beaches.     

沙障对流动沙丘区地表节肢动物分布及多样性的影响

沙障作为人工固沙植被恢复与保护绿洲和道路安全的一种手段,可以有效阻止沙丘移动,改变流动沙丘地表生态水文过程,进而影响节肢动物多样性及营养结构及功能变化。鉴于此,选取临泽县中部沙带为研究区,利用陷阱法系统调查了生物、物理沙障和流动沙丘区沙丘不同部位地表节肢动物分布及多样性。研究结果表明,沙障营建强烈影响了流动沙丘区地表节肢动物组成,生物和物理沙障区地表节肢动物的活动密度、物种丰富度及多样性均显著高于流动沙丘区,捕食性和其它食性节肢动物较植食性节肢动物对沙障营建的响应更为敏感。沙障还改变了沙丘地表节肢动物的分布规律,生物和物理沙障区地表节肢动物的活动密度从沙丘底部到顶部依次增加,而流动沙丘区地表节肢动物主要分布在沙丘中下部。谢氏宽漠王和尖尾东鳖甲在流动沙丘区主要分布沙丘的中下部,沙障营建导致沙丘顶部谢氏宽漠王和尖尾东鳖甲的活动密度大幅提高。此外,研究还发现生物和物理沙障对地表节肢动物的影响不同,生物沙障区地表节肢动物活动密度显著高于物理沙障区,捕食性和东鳖甲属等其它食性节肢动物的活动密度在生物沙障区均高于物理沙障区。总之,沙障营建及类型差异强烈影响地表节肢动物的分布及多样性,它通过资源上行效应和土壤物理环境的改变提高了地表节肢动物的多样性及营养结构,从而影响了土壤生态系统结构及功能变化过程。     

Effect of sand shape on evaporation from soil surface

Summary Loss of water through evaporation for different types of soils was examined. Soils were prepared from a clay soil and multiangular or platy sand in different proportions. The evaporation curves are of the type z=a+bx+cx² but with different slopes. Both soils had the same percentage of clay and sand but platy-sand soils behaved as if they had a finer texture.     

Structure, Pattern and Mechanisms of Formation of Seed Banks in Sand Dune Systems in Northeastern Inner Mongolia, China

A comparison of structure and pattern of the soil seed bank was made between active and stabilized sand dunes in northeastern Inner Mongolia, China. The objective of this paper was to determine the significance of seed bank in vegetation restoration of sand dunes. The results showed that (1) average seed density decreased from stabilized sand dune to interdune lowland of stabilized sand dune, to interdune lowland of active sand dune, and to active sand dune; (2) horizontally, along the transect from interdune lowland to ecotone and to sand dune top, a ‘V’ shaped pattern was presented in the active dune system, and a reverse ‘V’ shaped pattern in the stabilized sand dune system; (3) vertically, the proportion (accounting for the total seeds) of seeds found in 0–20 mm soil profile decreased from stabilized sand dune to interdune lowland of stabilized sand dune, to interdune lowland of active sand dune, and to active sand dune. The same order was also found in 20–50 mm and 50–100 mm soil profiles; (4) the Sokal and Sneath similarity indices in the species-composition between soil seed bank and above-ground vegetation were ranked as: the stabilized sand dune (24%) > the interdune lowland of active sand dune (21%) > the interdune lowland of stabilized sand dune (18%) > the active sand dune (5%); and (5) vegetation restoration of active sand dunes depends on the dispersal of seeds from nearby plant communities on the interdune lowlands. Much effort must be made to preserve the lowlands, as lowlands are the most important seed reservoir in the active sand dune field.     

Uptake of phosphorus and lead by Brassica juncea and Medicago sativa from chloropyromorphite

In situ remediation of lead (Pb)-contaminated soils via phosphate amendments has been extensively used to immobilize Pb as pyromorphite. However, in phosphorus (P) deficient soils, plants may develop extensive root systems to access P in any P-containing minerals, thereby affecting the stability of Pb5 (PO4)3Cl (Chloropyromorphite; CP). We grew Brassica juncea and Medicago sativa in sand culture to evaluate the stability of CP in the presence or absence of hydroxyapatite (HA) as P source. Treatments (per kilogram of sand) watered with P-nutrient solution were control [PC0, (without CP)], 1, and 5 g Pb as CP [PC1, and PC5] and 0.45 g P as HA (PA), and those of watered with P-free nutrient solution were 1 and 5 g Pb as CP [NC1 and NC5], 5 g Pb as CP plus 0.45 g P as HA [NAC5], and 0.45 g P as HA [NA]. Plants in NC1 and NC5 treatments showed stunted growth and reductions in shoot elongation and leaf size. Among CP treated pots, the highest shoot Pb uptake was observed in NAC5 treatment. The results suggested that Pb accumulation and translocation in the plants was markedly higher in P-sufficient conditions than in P-deficient conditions.     

毛乌素沙地沙丘土壤含水量特点——兼论老固定沙地上油蒿衰退原因

土壤表面干沙层在冬春少雨季节较厚,流动沙地的又明显地大于固和地的。流动沙地地表干沙层以下的土壤含水量一般在于同深化度固定沙地的,特别是在报系密集分布的土层。科季或早春土壤含水量比较低,雨季的明显较高,雨季结束后,土层中的水分在重力的作用下会向深层运动,导致根系层土壤含水量下降。在植物生长季,缺少降雨时,因少地的土土壤水量会因植物的蒸腾消耗而变得很低（１％～２％）,而流动沙地的不受或受此影响很小。地     

LCA of Finer Sand in Concrete (5 pp)

Goal, Scope and Background Due to the limited spatial possibilities for the extraction of coarse sand available from land sources, and the abundant availability of finer sands in land and marine sources, the Dutch government aims to allow for the use of finer sand used in the Netherlands. The application of finer sand in concrete requires adaptations in the concrete composition (additional cement, additional superplasticiser, or other aggregates) to maintain workability. In order to examine if these adaptations result in shifts from (the expected) land use effects to other environmental effects, an LCA of finer sand in concrete was carried out.Methods Besides the common CML-method, an experimental characterisation method for land use, was applied.Results and Discussion, Conclusion The results show that the application of finer sand indeed results in lower land use effects. Compositions with additional cement and other aggregates result in somewhat higher scores on the usual CML impact categories. Compositions with extra superplasticiser result in roughly similar environmental effects as the current compositions.Recommendation and Perspective The conclusions were used to formulate recommendations for the national policy on fine sand in concrete. Due to a change in priorities, it is not sure if and which organisation will use the conclusions.