祁连山亚高山灌丛林叶面积指数与冠层氮、磷的关系

氮和磷作为植物体内重要的生命元素,在植物群落的生长发育过程中发挥着重要的作用。为了明确祁连山亚高山灌丛林叶面积指数与冠层氮、磷之间的关系,本文通过对祁连山亚高山灌丛林不同植被类型(箭叶锦鸡儿、高山吉拉柳、金露梅)及不同放牧处理(羊群、牦牛,未放牧)条件下灌丛群落的叶面积指数(LAI)与叶片氮积累量(TFN)、叶片磷积累量(TFP)比较发现,在整个亚高山灌丛群落中,LAI与TFN和TFP之间都有较强的相关性,并且TFN和TFP比值的变化表明不同植被类型叶片的生长都受到N、P的共同限制,只是随着LAI的增加,高山吉拉柳主要受到氮素的限制,箭叶锦鸡儿主要受到磷素的限制,而金露梅则受到N、P的共同限制;在不同放牧条件下,单位面积LAI对应的TFN的值较高而TFP的值较低,说明动物通过对植被的啃食可能会改变群落的模式,在一定程度上限制磷的摄入。LAI、N、P之间的耦合关系表明了亚高山灌丛群落的LAI在物种组成、放牧和冠层密度上存在差异,但仍然受到N和P的约束。研究结果有利于探索水分限制条件下祁连山灌丛林生态系统植物叶片与养分元素之间关系,对于研究干旱区高寒灌丛生态系统在全球气候变化中的作用及其对全球气候变化的响应与反馈,具有重要的理论价值和实践意义。     

再探温跃层有孔虫B/Ca与温度和[CO32-]的依赖性及其在24 ka以来热带西太平洋次表层碳酸盐系统重建中的应用

The B/Ca ratio of planktonic foraminifer shells has been used as a proxy for reconstructing past ocean carbonate chemistry. However, recent studies have revealed significant uncertainties associated with this proxy, such as whether seawater temperature or [ CO_3~(2-)] is the dominant control on the partition coefficient(K_D) of planktonic foraminiferal B/Ca. To address these uncertainties and thus improve our understanding of the planktonic foraminiferal B/Ca proxy, we analysed B/Ca ratios in the tests of Neogloboquadrina dutertrei(300–355 μm) and Pulleniatina obliquiloculata(355–400 μm) in surface sediment samples from the tropical western Pacific and South China Sea. The relationship between these B/Ca ratios and bottom water calcite saturation states(Δ[ CO_3~(2-)]) is weak, thus suggesting only a small dissolution effect on the B/Ca of the two species. The correlation coefficients(R~2) between the B/Ca ratios of N. dutertrei and P. obliquiloculata and environmental parameters(e.g., temperature, salinity, phosphate, DIC and ALK) in the tropical western Pacific and South China Sea are not high enough to justify using B/Ca ratios as a palaeoenvironmental proxy in the study areas. The significant correlation between K_D values of N. dutertrei and P. obliquiloculata and carbonate system parameters(e.g.,[ CO_3~(2-)], DIC, ALK, pH and [ HCO_3~-]) in the study area reflect chemical links between the K_D denominator and these variables. Based on our surface sediment calibration, an empirical relationship between the K_D of N.dutertrei and temperature is proposed in the tropical western Pacific. We also generated a record of B/Ca ratios in N. dutertrei(300–355 μm) from Core MD06-3052 in the tropical western Pacific over the past 24 ka to evaluate the application of the revised B/Ca proxy method. Based on the reconstructed empirical relationship for B/Ca and subsurface seawater ALK, we estimated subsurface seawater carbonate system parameters in the tropical western Pacific since 24 ka. In general, the estimated subsurface seawater pH and [ CO_3~(2-)] show an increase with time, and the record of subsurface seawater pCO_2 shows a decrease with time, in the tropical western Pacific over the past 24 ka. The consistent trends in subsurface seawater pCO_2 and opal flux during deglaciation may imply that the reported increase in subsurface water pCO_2 in the study area was promoted by enhanced upwelling in the Southern Ocean.     

西南大西洋乌拉圭近海双船拖网捕捞调查

为促进我国海洋渔业"走出去",进一步发展远洋捕捞业,文章调查西南大西洋乌拉圭近海双船拖网捕捞的渔具和渔法等,并提出生产建议。研究结果表明:双船拖网的渔具包括渔船、网具、纲索和属具,网身采用加目和减目编缝的方式缝合而成;渔法包括放网准备、放网、曳网、起网和网具养护等环节;针对渔场、渔期和捕捞对象,应把握捕捞产量、成本和航次的关系,并结合主捕对象的生活习性,合理规划生产。     

基于双树复小波的CBERS-02B星遥感影像融合及评价

以CBERS-02星全色、多光谱图像及IKONOS多光谱图像为数据源,利用离散小波变换和双树复小波变换进行融合试验。结果表明,双树复小波变换在空间细节表现力和光谱保持方面能够较好地达到平衡,较离散小波变换更能提高图像融合质量。通过融合方法对比分析可知,02B星全色波段不仅与其多光谱波段融合能够得到信息更加丰富的图像,而且与其它传感器数据融合同样有很好的目视效果和可读性,具有较大的应用前景。     

Evaluation of Inference Adequacy in Cumulative Logistic Regression Models: An Empirical Validation of ISWRidge Relationships

Internal solitary wave propagation over a submarine ridge results in energy dissipation, in which the hydrodynamic interaction between a wave and ridge affects marine environment. This study analyzes the effects of ridge height and potential energy during wave-ridge interaction with a binary and cumulative logistic regression model. In testing the Global Null Hypothesis, all values are p 〈0.001, with three statistical methods, such as Likelihood Ratio, Score, and Wald. While comparing with two kinds of models, tests values obtained by cumulative logistic regression models are better than those by binary logistic regression models. Although this study employed cumulative logistic regression model, three probability functions p^1, p^2 and p^3, are utilized for investigating the weighted influence of factors on wave reflection. Deviance and Pearson tests are applied to cheek the goodness-of-fit of the proposed model. The analytical results demonstrated that both ridge height （X1 ） and potential energy （X2 ） significantly impact （p 〈 0. 0001 ） the amplitude-based refleeted rate; the P-values for the deviance and Pearson are all 〉 0.05 （0.2839, 0.3438, respectively）. That is, the goodness-of-fit between ridge height （ X1 ） and potential energy （X2） can further predict parameters under the scenario of the best parsimonious model. Investigation of 6 predictive powers （ R2, Max-rescaled R^2, Sorners＇ D, Gamma, Tau-a, and c, respectively） indicate that these predictive estimates of the proposed model have better predictive ability than ridge height alone, and are very similar to the interaction of ridge height and potential energy. It can be concluded that the goodness-of-fit and prediction ability of the cumulative logistic regression model are better than that of the binary logistic regression model.     

Evaluation of Inference Adequacy in Cumulative Logistic Regression Models： An Empirical Validation of ISW-Ridge Relationships

Internal solitary wave propagation over a submarine ridge results in energy dissipation, in which the hydrodynamic interaction between a wave and ridge affects marine environment. This study analyzes the effects of ridge height and potential energy during wave-ridge interaction with a binary and cumulative logistic regression model. In testing the Global Null Hypothesis, all values are p<0.001, with three statistical methods, such as Likelihood Ratio, Score, and Wald. While comparing with two kinds of models, tests values obtained by cumulative logistic regression models are better than those by binary logistic regression models. Although this study employed cumulative logistic regression model, three probability functions p^1, p^2 and p^3, are utilized for investigating the weighted influence of factors on wave reflection. Deviance and Pearson tests are applied to check the goodness-of-fit of the proposed model. The analytical results demonstrated that both ridge height (X1) and potential energy (X2) significantly impact (p<0.0001) the amplitude-based reflected rate; the P-values for the deviance and Pearson are all >0.05 (0.2839, 0.3438, respectively). That is, the goodness-of-fit between ridge height (X1) and potential energy (X2) can further predict parameters under the scenario of the best parsimonious model.Investigation of 6 predictive powers (R2, Max-rescaled R2, Somers'D, Gamma, Tau-a, and c, respectively) indicate that these predictive estimates of the proposed model have better predictive ability than ridge height alone, and are very similar to the interaction of ridge height and potential energy. It can be concluded that the goodness-of-fit and prediction ability of the cumulative logistic regression model are better than that of the binary logistic regression model.     

5种中草药对美国红鱼生长和免疫机能的影响

用分别含连翘(Forsythia suspensa)、猪苓(Polyporus umbellatus)、黄芩(Radix scutellariae)、茯苓(Poria cocos)和黄连(Coptis chinensis)水提取物的配合饵料饲喂美国红鱼(Sciaenops ocellatus),研究其对美国红鱼(Sciaenops ocellatus)生长和免疫机能的影响.结果表明,投喂含有黄芩和茯苓的药饵可使美国红鱼的体长增长率和相对增质量率显著高于对照组(P<0.05);投喂5种含中草药的药饵后,美国红鱼血液白细胞的吞噬活性有明显提高,投药后3 d,除茯苓组外,其余各组吞噬百分比(PP)与对照组之间均差异极显著(P<0.01);在投药后3 d或投药后7 d,连翘、黄芩和黄连组的吞噬指数(PI)与对照组相比有显著(P<0.05)或极显著(P<0.01)差异.在停投药饵后7 d,除茯苓组外,其余各组PP、PI与对照组相比仍有显著差异(P<0.05).同时,美国红鱼血清溶菌酶活性也有显著提高,投药后7 d,溶菌酶活性与对照组之间差异极显著(P<0.01),但在停投药饵后7 d,溶菌酶活性与对照组之间无显著差异(P>0.05);投药28 d后,利用哈维氏弧菌(Vibrio harveyi)人工感染美国红鱼,黄芩组的相对免疫保护率最高,达88.9%,连翘组次之,茯苓组最低.     

象山港氮、磷营养盐环流和分布规律的研究

采用定点监测分析方法,研究了象山港狭湾内设置的六个固定站位1992-2007年时间段内的硝酸氮(NO3-N)、亚硝酸氮(NO2-N)、铵氮(NH4-N)和磷酸盐(PO4-P)浓度的监测数据,探讨了象山港狭湾内(122°00'E以西)氮、磷营养盐的环流和分布规律.结果表明,(1)除个别年份外,16年内硝酸氮、亚硝酸氮、铵氮和磷酸盐浓度的空间分布,从港顶1号站向港口6号站呈降低趋势,其中以PO4-P、NO2-N的降低趋势最为明显,而NH4-N的降低趋势相对较弱.(2)NO3-N的空间变化规律较为复杂,并且3号站的浓度往往达到最大值.(3)无论是平水期(4月)还是丰水期(7月),表层盐度均低于底层,而表层温度高于底层;盐度从港顶1号站向港口6号站递增,而温度递减.这种分布规律基本上可用余环流模式进行解释,但余环流输运并不是促使营养盐入海的唯一原因,潮振荡的垂向剪切造成的纵向弥散和潮混合亦对营养盐输运有重大贡献.(4)与1992年相比,2007年各站的NO3-N浓度几乎都增加了一倍,PO4-P浓度增幅更大,说明象山港的氮、磷污染与日俱增.     

应用于村镇信息自助平台的电子地图构件关键技术研究

从构件化村镇信息自助平台的低成本、易定制的特点出发,针对其中电子地图构件在地图浏览和交互查询中存在的网络负载大、响应速度慢等技术问题,研究了传统We-bGIS空间数据网络发布模式及其不足,探讨了基于AJAX、地图切片、多级缓存技术的电子地图发布解决方案,并实现了在村镇信息自助平台上的应用.     

The Evaluation on Biological Properties of Carboxymethylchitosan and Carboxymethyl-chitin

Carboxymethyl-chitosan and carboxymethyl-chitin were prepared with the methods developed in our laboratory. The DS （degree of substitution） and DD （degree of deacetylation） of the carboxymethyl-chitosan were 103.14% and 97.18% respectively, while the DS of the carboxymethyl-chitin was 96.37%. Their effects on human fibroblasts, intradermal irritation test, in vitro and vivo degradability, and biocompatibility were evaluated. The results indicate that the polysaccharides at low concentrations can facilitate the growth of human fibroblasts and the carboxymethyl-chitosan at 100 μg mL^-1 is the most effective. The polysaccharides at higher concentrations, however, inhibit the growth of fibroblasts. The PII （Primary Irritation Index） values of CM-chitosan and CM-chitin are both 0.0, which shows that they have no irritation reaction. Both of the polysaccharides show good degradability and biocompatibility. Carboxymethyl-chitin degrades faster in vitro than carboxymethyl-chitosan. The latter, however, has no inflammatory reaction after being implanted in vivo for 7 d and shows better biocompatibility. This study may provide a scientific basis for the use of earboxymethyl-ehitosan and carboxymethyl-chitin as biomaterials.