原地自生封堵转向酸的研究

利用酸化材料自身水解及水解产物与钙离子发生沉淀反应的原理,研制出了一种新型转向酸。对该转向酸进行了溶蚀实验、静态腐蚀速率、酸液驱替及渗透率以及残酸界面张力等测定,并采用SEM和XRD检测手段对酸液转向机理进行了分析。研究结果表明:该转向酸比盐酸具有更好的缓速性及低腐蚀性,在中低渗碳酸盐岩心中转向能力达到15%,为盐酸的5倍以上,且转向酸残酸的黏度接近清水、油水界面张力低于10 m N/m,能顺利返排。SEM和XRD检测手段结果表明,该转向酸可在岩石表面产生少量二水硫酸钙微溶物,延缓酸岩反应,从而促使酸液向低渗储层转向。该原地自生封堵转向酸可实现酸液就地转向,达到均匀布酸目的。

The current status, threats and protection way of Sanjiang Plain wetland, Northeast China

The Sanjiang Plain is a vast area of alluvial floodplains and low hills in northeast Heilongjiang Province. It is the largest tract of wetlands in China and East Asia outside of Siberia. 28 wetland nature reserves exist on the Sanjiang Plain, and three of them have been listed as wetlands of international importance to water bird conservation by the Ramsar Convention Bureau. The wetlands of Sanjiang Plain are noteworthy for its rich biodiversity, but they continue to decline in area and deteriorate in quality currently. The main threats or constrains, immediate cause, root cause and required response are analyzed in this paper, and the four aspects opinion such as improvement of watershed management, enhancement of protection and restoration of habitats and biodiversity, alternative livelihoods of rural residents living in and near natural wetland reserve, and reinforcement of capacity building of natural reserves are brought forward as the effective measures for the Sanjiang Plain wetland protection.

Study on security and protection of original ecotourism resources in the mountain areas of western Guangxi

Original ecotourism resources mainly refer to natural and human original ecotourism resources, and it＇s of fragility, rarity and irreversibility. As a valuable historic heritage and hnportant tourism resources, it plays a significant role in developing tourism and economy in such areas as the underdeveloped areas, the mountain areas and mimority areas. The tourism resources in the western mountain areas of Guangxi owe ,superiorities and characteristics ＇o their original ecology, Yet, western Guangxi is an ethnic region with fragile karst eco-environment, so it is specialto exploit the tourism resources. The paper defines original eeotourism and analyses the specialties and advantages of the original ecotourism resources as well as thefrailty of the ecotourism resources of the region. The ways of thinking are put forward for safe preservation and sustainable development of the original ecotourism resources, i.e. carrying out measures for the multi-grade protection of heritage resources, setting up a ethnic eco-museum/ ethnic culture eco-park and a gene pool of ethnic cultures, etc.

Assessing Threats and Setting Conservation Priorities for Plant Species between Forest and Meadow Ecotone in Sanjiangyuan Nature Reserve, China

In order to understand the pattern and status of plant species in the forest-meadow ecotonein Sanjiangyuan Nature Reserve, this study was undertaken through expert consultation, literaturesurvey and fieldwork in various parts of the ecotone during 2002-2004. Based on 3 important systems,i.e. threatened status, genetic loss effect and use value, the list of threatened and prioritized plants wasestablished. In this paper, the threatened coefficient was defined as the criteria of category for threatenedplants, the conservation priorities coefficient summed by threatened coefficient, genetic coefficient anduse value coefficient was defined as the criteria of prioritized plants. In addition, 10 indicators toevaluate threatened grading and conservation priorities sequence were included in the 3 importantsystems. The weights of 3 systems and 10 indicators were given through expert consultation andanalytic hierarchy process. Ten indicators were given scores based on the subcriteria, respectively, andall the scores of the 3 systems were summed up for each species, then contrasted to the criteria ofthreatened grading and conservation priorities for plant species. The status of endangerment andconservation priorities of plant species were analyzed, and the results showed that the number ofendangered species was 2, vulnerable species 37, near threatened species 140, safe species 767; the firstconcern category had 4 species, the second concern category 18, the third concern category 150 and theleast concern category 774.