Assessing the short‐term effects of capture,handling and tagging of sandgrouse

Capturing and marking free‐living birds permits the study of important aspects of their biology but may have undesirable effects. Bird welfare should be a primary concern, so it is necessary to evaluate and minimize any adverse effects of procedures used. We assess short‐term effects associated with the capture, handling and tagging with backpack‐mounted transmitters of Pin‐tailed Pterocles alchata and Black‐bellied Pterocles orientalis Sandgrouse, steppe birds of conservation concern. There was a significantly higher mortality (15%) during the first week after capture than during the following weeks (< 2.5%) in Pin‐tailed Sandgrouse, but no significant temporal mortality pattern in Black‐bellied Sandgrouse. In Pin‐tailed Sandgrouse, mortality rate during the first week increased with increasing relative transmitter and harness weight regardless of season, and with increasing handling time during the breeding season. There were no significant differences in mortality rate between study areas, type of tag, sex or age or an effect of restraint time. These results suggest the use of lighter transmitters (< 3% of the bird's weight) and a reduction of handling time (< 20 min), particularly during the breeding season, as essential improvements in procedure to reduce the mortality risk associated with the capture, handling and tagging of these vulnerable species.     

不同光强下高锰对黄瓜光合作用特性的影响

采用营养液培养的方法,研究了不同光强下高锰对黄瓜植株生长、叶绿素含量、叶绿素荧光参数和光合作用的影响.结果表明,高锰处理抑制了黄瓜植株的生长,与弱光处理相比强光下抑制幅度更加显著.强光下,高锰处理显著降低叶绿素含量,但降低光强却增加其含量.强光下,高锰处理显著降低原初光能转换效率(F_v/F_m)、光合电子传递量子效率(ΦPSII)和光化学猝灭系数(qP);弱光下,高锰处理对F_v/F_m和qP无显著影响.高锰处理使净光合速率(P_n)和气孔导度(G_s)下降.尤其是在强光下下降幅度更大.高锰处理使细胞间CO₂浓度(C_i)在强光下升高,而在弱光下则下降.与C_i相反,高锰处理使气孔限制值(L_s)在强光下下降,而在弱光下上升.因此,强光下高锰胁迫使净光合速率下降可能是由非气孔限制引起的,而弱光下高锰处理使净光合速率下降可能是由气孔因子限制引起的.     

RESPONSES OF FLORAL TRAITS TO SELECTION ON PRIMARY SEXUAL INVESTMENT IN SPERGULARIA MARINA: THE BATTLE BETWEEN THE SEXES

Two widespread assumptions underlie theoretical models of the evolution of sex allocation in hermaphroditic species: (1) resource allocations to male and female function are heritable; and (2) there is an intrinsic, genetically based negative correlation between male and female reproductive function. These assumptions have not been adequately tested in wild species, although a few studies have detected either genetic variation in pollen and ovule production per flower or evidence of trade-offs between male and female investment at the whole plant level. It may also be argued, however, that in highly autogamous, perfect-flowered plant taxa that exhibit genetic variation in gamete production, strong stabilizing selection for an efficient pollen:ovule ratio should result in a positive correlation among genotypes with respect to mean ovule and mean pollen production per flower. Here we report the results of a three-generation artificial selection experiment conducted on a greenhouse population of the autogamous annual plant Spergularia marina. Starting with a base population of 1200 individuals, we conducted intense mass selection for two generations, creating four selected lines (high and low ovule production per flower; high and low anther production per flower) and a control line. By examining the direct and correlated responses of several floral traits to selection on gamete production per flower, we evaluated the expectations that primary sexual investment would exhibit heritable variation and that resource-sharing, variation in resource-garnering ability, or developmental constraints mold the genetic correlations expressed among floral organs. The observed direct and correlated responses to selection on male and female gamete production revealed significant heritabilities of both ovule and anther production per flower and a significant negative genetic correlation between them. When plants were selected for increased ovules per flower over two generations, ovule production increased and anther production declined relative to the control line. Among plants selected for decreased anthers per flower, we observed a decline in anther production and an increase in ovule production relative to the control line. In contrast, the lines selected for low ovules per flower and for high anthers per flower exhibited no evidence for significant genetic correlations between male and female primary investment. Correlated responses to selection also indicate a genetically based negative correlation between the production of normal versus developmentally abnormal anthers (staminoid organs); a positive correlation between the production of ovules versus staminoid organs; and a positive correlation between the production of anthers and petals. The negative relationship between male versus female primary investment supports classical sex allocation theory, although the asymmetrical correlated responses to selection indicate that this relationship is not always expressed.     

Comparison of Different Standard Methods to Evaluate the Total Concentrations of Heavy Metals in Waste Rock

The mining industry is a very rapidly increasing production sector in Finland. Many new mines have been opened recently and others are in the planning phase. Mining legislation has been recently revised and compilation of an ID-directive (Industrial Emission Directive, 2010) required to implement environmental law revision is in progress. The aim of this study was to compare different digestion methods recommended by the Finnish Environmental Administration for threshold and guideline value determinations in the Finnish PIMA Decree (214/2007) and Government Decree (591/2006) concerning recovery of certain wastes in earth construction. Altogether six methods were tested, of which five were microwave-assisted acid digestion methods: ISO 11466, EPA Method 3051A (aqua region), EPA Method 3051A (HNO₃), EPA Method 3051A (HNO₃/HCl), and SFS-EN 13656, while one was a fusion method with lithium tetraborate (ASTM C 1391 - 95). The results showed that concentrations of heavy metals (As, Cd, Co, Cu, Ni, Pb, Sb, V, and Zn) can be determined reproducibly with standard methods, but the chemical method used can have a significant impact on the results. This conclusion is very important, because the measured heavy metal values can affect the classification and processing of waste materials, and thereby can significantly impact the cost of treatment.     

兴安落叶松种群格局的分形特征信息维数

种群格局信息维数能够刻划格局强度的尺度变化程度,揭示出种群个体分布的非均匀性状况。采用信息维数对大兴安岭兴安落叶松种群格局的研究显示,各类兴安落叶松林中兴安落叶松种群格局的信息维数大小依次为越桔－兴安落叶松林（１．４８０）＞杜香－兴安落叶松林（１．３７３）＞杜鹃－兴安落叶松林（１．３２１）＞草类－兴安落叶松林（１．０９３）。虽为群落建群种,兴安落叶松种群格局的信息维数较低（＜１．５,远离２）,格局     

Rhipsalis (Cactaceae): loss and gain of floral rewards is mirrored in range sizes and distribution patterns of species

Autogamous species are usually distinguishable from xenogamous relatives by smaller flowers, fewer or even no floral rewards and lower pollen–ovule (P/O) ratios. Many Rhipsalis spp. are small flowered, selfing and include the most widespread species in Cactaceae. However, Rhipsalis also includes a large number of narrowly endemic species and is most diverse in the Atlantic rainforests of Brazil. To investigate the evolution of floral function and the correlation between floral function and range size, we analysed display size, floral reward and P/O ratios of Rhipsalis and its closest relatives, reconstructed ancestral traits and related these patterns to the distributions and range sizes of the species. Display size and sugar amount are reduced in subgenera Goniorhipsalis and Rhipsalis and secondarily increased in Phyllarthrorhipsalis, whereas the P/O ratio is decreased in subgenera Rhipsalis and Phyllarthrorhipsalis. We interpret this pattern as a switch from a predominantly xenogamous to an autogamous reproductive system, followed by a return to a predominantly xenogamous system. None of the floral parameters shows significant correlations with range size, except for display size. Nevertheless, those species with the smallest flowers, lowest sugar amounts per flower and lowest P/O ratios occur either outside southeastern Brazil and/or have comparatively large distribution ranges. Almost all Rhipsalis spp. occurring outside the Atlantic rainforests are restricted to the clade formed by subgenera Rhipsalis and Phyllarthrorhipsalis. Thus, we believe that the evolution of an autogamous reproduction system enabled this lineage of Rhipsalis to diversify and spread in the Atlantic rainforests, in the rest of the Neotropics and even spread to the Old World, where it is the only member of the family.     

连翘花的结构与繁育系统研究

通过定株观察、解剖和人工套袋交叉授粉试验对连翘花的生长发育和繁殖系统进行研究.结果表明:(1)连翘具有2种避免自交的方式,雌雄异位和雌雄异熟.其雌雄异位表现为长雄蕊短雌蕊花型和短雄蕊长雌蕊花型;雌雄异熟表现为长雄蕊短雌蕊花型为雄蕊先于雌蕊成熟,短雄蕊长雌蕊花型表现为雌蕊先于雄蕊成熟.(2)连翘花P/O值测定和户外套袋交叉授粉试验显示,P/O值为2 000±300;不同类型花的异花授粉结果率在50.64%~80.32%,其中短型花的花粉授到长型花柱头的结果率最高,达80.32%,而长型花和短型花的同型花授粉结果率分别为2.92%和34.15%,表明连翘的异花授粉结果率高于自花授粉,以异交为主,其繁育系统属兼性异交.研究结果认为,连翘雌雄异位和雌雄异熟是其自然结果率低下的主要原因,为进一步探讨连翘在木犀科中的系统进化提供了生殖生态学的依据.     

An efficient ligation method in the making of an in vitro virus for in vitro protein evolution

The “in vitro virus” is a molecular construct to perform evolutionary protein engineering. The “virion(=viral particle)”(mRNA-peptide fusion), is made by bonding a nascent protein with its coding mRNA via puromycin in a test tube for in vitro translation. In this work, the puromycin-linker was attached to mRNA using the Y-ligation, which was a method of two single-strands ligation at the end of a double-stranded stem to make a stem-loop structure. This reaction gave a yield of about 95%. We compared the Y-ligation with two other ligation reactions and showed that the Y-ligation gave the best productivity. An efficient amplification of the in vitro virus with this “viral genome” was demonstrated. Published: October 28, 2002     

DISTRIBUTION AND PHYSIOLOGICAL DETERMINANTS OF BLUE-GREEN ALGAL NITROGEN FIXATION ALONG A THERMOGRADIENT1

The capacity of thermal algal-bacterial mats to fix nitrogen (N₂) was examined in an alkaline thermal stream, Rabbit Creek, of Yellowstone National Park. Nitrogenase activity and nitrogen-fixation rates of mat cores placed in serum bottles and incubated in situ were estimated by the acetylene-reduction technique. Active nitrogenase was not detected at 60 or 65 C in either the blue-green algal or bacterial undermat components of the mats. Acetylene was reduced by all mats ≤55 C along the thermogradient; mean fixation estimates for the mats ranged from 7 to 5,028 nmoles N₂ fixed · mg Chl a^?1· hr^?1. Maximum fixation occurred at 35 C in the stream; statistical comparison of mean rates ordered the thermogradient mats according to estimated activities: 35 > 40 > 30 > 50 ≥ 55 ≥ 45 C. Mats (≤40 C) dominated by species of Calothrix accounted for ca. 97% of the total nitrogen fixation observed in the stream; the remaining activity was associated with mats containing Mastigocladus laminosus Cohn. Light intensity significantly affected fixation rates of the Calothrix mats which responded in a linear fashion from 9–100% full sunlight (ca. 1,900 μEin · m^?2· sec^?1). Calothrix mats from 30 and 40 C had maximum nitrogenase activity at their growth temperature suggesting that nitrogen fixation along the thermogradient was optimally adapted to in situ temperatures.