关于GIS空间信息共享的若干再思考

空间信息共享是一个涉及理论、技术、标准与环境的综合的复杂问题。其中,空间数据模型理论是内在的核心要素,共享技术、空间信息标准与政策法规环境则是外在的必要条件。综合论述各要素的内涵、发展与重要意义,得出结论:综合、集成、分布式的海量空间数据模型亟待突破,网络、网格与数据库技术需与空间信息技术进一步融合,开放环境下的空间数据标准需要整合与完善,并呼吁理性的政策法规等社会环境。     

顾及季节性变化的日本区域加权平均温度建模

利用2014~2018年的ERA-Interim数据建立适用于日本区域的加权平均温度模型,分析其误差并进行季节性改正。结果表明：1）建立的线性加权平均温度模型精度比Bevis模型提高约16%;2）线性模型的残差时间序列存在季节性变化,因此对模型进行季节性改正,改正后的模型精度比Bevis模型和线性模型提高约37%和25%;3）将3种模型与探空站积分Tm进行比较,进一步说明季节性改正后模型的优越性。     

Impact assessment and protection of outstanding landscape integrity in a natural heritage site: Fairy valley, Kanas Nature Reserve, Xinjiang, China

The essential purpose of the Convention Concerning the Protection of World Cultural and Natural Heritage is to protect the integrity of heritage values. Outstanding landscape is the core embodiment of the aesthetic value of a natural heritage site. This paper proposes a new assessment method from the point of view of the protection of heritage values. It is used to measure the degree of outstanding landscape integrity under the human and natural impact in natural heritage sites. This paper employ three indices, a visual index of outstanding landscape, a harmony index of the artificial landscape and a disturbance index of damaged landscape, to measure the impact of landscape integrity. The impact assessment model is based on a weighted combination of the three indices. The study site is the Fairy Valley, Kanas Nature Reserve, Xinjiang Uygur Autonomous Region in northwest China. The information employed is derived from field investigation and a Digital Elevation Model (DEM). A comprehensive evaluation of the Fairy valley was undertaken and it was determined that the outstanding landscape values are being compromised. Three protection methods are proposed to reduce the adverse effects and maintain landscape quality, thereby providing site managers with suggestions for the protection of natural heritage values. More broadly, the paper contributes novel methods of landscape assessment applicable to natural protected areas.     

基于三元组系数的水印算法

提出的水印方案堆于离散小波变换,利用三元组小波系数间的关系而不是单个小波系数来嵌入和提取水印.水印提取时不需要使用原始图像,算法简单,容易实现.实验结果表明该算法对大多数图像处理和攻击具有较好的鲁棒性.     

Nitroaromatic stimulation of superoxide production in three species of freshwater fish

Nitroaromatic compounds frequently contaminate aquatic systems and may, therefore, impact fish. However, a known pathway of nitroaromatic toxicity in mammals, that of nitroaromatic stimulated superoxide (O₂⁻) production, has yet to be addressed in fish. In this study we investigated this pathway in three species of freshwater fish-channel catfish (Ictalurus punctatus), largemouth bass (Micropterus salmoides) and rainbow trout (Salmo gairdneri)-exposed to nitrofurantoin (NF), p-nitrobenzoic acid (PNBA) and m-dinitrobenzene (MDNB). Our results indicate that these nitroaromatics elicit a stimulation of O₂⁻ production by fish liver fractions. Additionally, results suggests a similarity between, fish and mammals in the nitroreductases which mediate nitroaromatic activation and subsequent O₂⁻ production. These findings indicate a potential toxic consequence of fish exposure to nitroaromatic contaminants in aquatic systems.     

Cenozoic Volcanism in South China Sea and Its Vicinity and South China Sea Spreading

The rock series, rock types and Sr-Nd isotopic dating of the Cenozoic volcanic rocks in the South China Sea are similar to those in its vicinity. On the basis of the spreading age of the South China Sea, the Cenozoic volcanic rocks are divided into three stages: the pre-spreading stage, the spreading stage and the post-spreading stage. The deep process characteristics of the asthenosphere and lithosphere may be inferred from the study on primary basaltic magma. The top layers of the asthenosphere both in the spreading stage and in the pre-spreading stage are closer to the earth surface than that in the post-spreading stage. From the pre-spreading stage to the spreading stage, the top layer of the asthenosphere decreased in depth, while the amount of interstitial partial melts increased. The evolution of the primary basaltic magma shows a progressive evolution sequence of the rifting volcanism and a faster lithospheric spreading velocity. From the spreading stage to the post-spreading stage, the top layer of the asthenosphere gradually increased in depth, but the amount of interstitial partial melts decreased. The evolution of primary basaltic magma shows a retrogressive evolution sequence of the rifting volcanism and a gradual decrease in the lithospheric spreading velocity. The depth recognized by the study on the Cenozoic volcanism demonstrates the deep environment for the formation and evolution of the South China Sea.     

楚科奇海与白令海表层沉积中的钙质和硅质微体化石研究

通过对北冰洋楚科奇海和令海41个表层沉积样品中的有孔虫、介形类等钙质微体化石和硅藻、放射虫、海绵骨针等硅质微体化石的定量分析，发现表层沉积中浮游有孔虫几乎缺失，这可能与该区表层生产力相对低、碳酸盐溶解作用较强有关，而底栖有孔虫和硅质微体化石的丰度分布则明显受表层沉积物类型、表层初级生物生产力和碳酸盐溶解作用所控制。其中，北冰洋楚科奇海陆架区有孔虫丰度和分异度低，含少量浅水介形类，放射虫在陆架浅水区缺失，但含有较多硅藻和海绵骨针等其它硅质微体化石，反映该区由于海冰、表层海水温度较冷而导致表歧初级生产力相对低。白令海陆坡区底栖有孔虫丰度比较科奇海高一个数量级，底栖有孔虫分异度也相对高，硅藻、放射虫、海绵骨针等硅质微体化石的丰度与钙质化石一样，其丰度比楚科奇海明显高，反映表层初级生产力相对高。根据白令海陆坡区底栖有孔虫和硅质微体化石丰度、底栖有孔虫胶结质壳比值的水深变化，推测该区碳酸盐溶跃层和补偿深度（CCD）相对浅，分别位于水深2000m和3800m处。     

蒲阳河流域地下水水化学及同位素特征

保定西部山前地区位于太行山及华北平原交界带,为缓解极端气候灾害对生产生活的影响,维持地下水资源的可持续开发利用,开展相关的地下水水化学及同位素特征研究。研究区地下水化学类型以HCO3—Ca·Mg、HCO3·SO4—Ca·Mg及SO4·HCO3—Ca·Mg为主,区内地下水主要来源于大气降水,流域内地表水补给地下水;地下水中化学成分为Ca2＋、Mg2＋、HCO-3、SO2-4,主要来源于岩石风化作用,同时受到人类活动的影响,地下水中硝酸盐含量明显升高;由于受到褶皱构造的控制,流域的上游及平原区均出现年龄大于60年的地下水,多数岩溶水年龄较复杂,从现代水到大于60年的水均有分布。研究成果为流域内水资源的合理开发利用提供建议,区内岩溶地下水的开发将在一定程度上缓解极端天气的影响。     

Physicochemical characterization of the microhabitat of the epibionts associated with Alvinella pompejana, a hydrothermal vent annelid

Alvinella pompejana is a polychaetous annelid that inhabits narrow tubes along the walls of high-temperature hydrothermal vent chimneys. The worm hosts a rich community of epibiotic bacteria that coats its dorsal surface. Although the worm tube microhabitat is a challenging environment to sample, characterizing the thermal and geochemical regime is important for understanding the ecology of the worm and its bacteria, as the worm spends most of its time inside the tube. We characterized the physicochemical conditions of diffuse hydrothermal flow inside inhabited worm tubes using in situ analysis and wet chemical analysis of discrete water samples. Thermistor probes deployed inside worm tubes measured temperatures ranging from 28.6°C to 84.0°C, while temperatures at tube orifices ranged from 7.5°C to 40.0°C. In situ electrochemical analysis of tube fluids revealed undetectable oxygen (<5 μM) and surprisingly low levels of free H₂S (<0.2 μM), with most of the sulfide existing as aqueous FeS molecular clusters. Acid-volatile sulfide measured on discrete samples of tube fluids ranged from 62.9 to 359.3 μM, while free sulfide (H₂S) ranged from undetectable (<0.2 μM) to 46.5 μM. The pH ranged from 5.33 to 6.40, and sulfate ranged from 22.5 mM to 27.5 mM. Nitrate ranged from 13.9 to 20.0 μM, whereas ammonium ranged from 2.5 to 9.7 μM. Total Fe ranged from 72.1 to 730.2 μM. Mn, Zn, Ni, V, P, and Cu were present in micromolar amounts; Pb, Cd, Co, and Ag were present in nanomolar levels. The worm tube fluids contained between 72% to 91% of Mg concentrations typically found in deep seawater. Plots of Mg concentrations vs. other fluid components showed that the tube fluid is geochemically altered from theoretical mixing values. Values of SO₄²⁻ were enriched inside the worm tube fluids, whereas NO₃⁻, Sr, Mn, Fe, Zn, and acid-volatile sulfide were depleted. The geochemistry of the tube microhabitat likely influences the structure of resident microbial communities.     

The Bulgheria canyon-fan: a small-scale proximal system in the eastern Tyrrhenian Sea (Italy)

The Bulgheria canyon-fan system in the eastern Tyrrhenian Sea displays well-developed, small-scale, fluvial-like features and has formed alongside the northern slope of the Sapri peri-Tyrrhenian basin. This study reveals, for the first time, the morphology and course of the present-day system as well as the buried elements based on a Digital Terrain Model and high-resolution seismic profiles interpretation. Two adjacent canyons (Infreschi and Luna) originate in the Cilento outer shelf at a short distance from each other and feed an intraslope basin fan through two main sub-parallel channels that run about 12 and 8 km, respectively. Channel and levee development seems to be controlled primarily by the local slope gradient and by Coriolis forces that induce a faster vertical growth of the right-side features, as is often observed in the Northern Hemisphere. Centrifugal forces, on the other hand, have induced episodic flow-stripping at the meander loops and bends, causing local destruction of the main channel levees rather than new levee growth at the outer bends. Overbank deposits are associated with overspill turbidite deposition in the mid fan where a topographic constraint occurs, whereas large-sediment, low-angle wave fields are mainly developed on the outer fan. Buried features and relict morphologies suggest that the Infreschi channel experienced at least two phases of re-incision since the final stages of the middle Pleistocene. Local re-adjustment of outer lobe growth due to channel avulsion and meander abandonment is possibly a consequence of relative base-level fluctuations. The sedimentary record of the mid and outer fan includes outrun mass wasting deposits from extensive failures of the Sapri slope. Indeed, a marked scar is present on the eastern side of the modern outer lobe that indicates the persistency of mass flow passages up to recent times. In addition to the environmental factors that are currently considered to cause canyon formation on the shelf margin, this study proposes the possibility that the head canyon branch close to the mainland was incised by massive and persistent underground freshwater flow from the adjacent aquifer when the sea-level was lower than at present.