Land Degradation Due to Salinization in Arid and Semi-arid Regions with the Aid of Geo-information Techniques

This study applied a computerized parametric methodology to monitor, map, and quantify land degradation by salinization risk detection techniques at a 1：250 000 mapping scale using geo-information technology. The northern part of the Shaanxi province in China was taken as a case. Multi-temporal remotely sensed materials of both Landsat TM and thematic maps （ETM＋） were used as the bases to provide comprehensive views of surface conditions such as vegetation cover and salinization detection. With ERDAS ver. 9.1 software, the Normalized Differential Salinity Index （NDSl） and Salinity Index （S.I.） were computed and then evaluated for land degradation by salinization. Arc/Info ver. 9.2 software was used along with field observation data （GPS） for analysis. Using spatial analysis methods, results showed that 19 973.1 km^2 （72%） of land had no risk of land degradation by salinization, 3 684.7 km^2 （13%） had slight land degradation by salinization risk, 2 797.9 km^2 （10%） had moderate land degradation by salinization risk, and 1 218.9 km^2 （4%） of the total land area was at a high risk of land degradation by salinization. The study area, in general, is exposed to a high risk of soil salinization.

Change in Sediment Load of the Yangtze River after Wenchuan Earthquake

On May 12, 2008, an earthquake of 8.0 magnitude on the Richter scale and its numerous aftershocks devastatingly hit Wenchuan County and its nearby region along the Longman Mountains in Sichuan Province, China. The heavy ruined area was up to 30,000km2 and 13% of its land surface was denuded by the extremely terrible quakes. The mountain collapses, landslides and debris flows induced by the earthquake not only scared the landscape at the immense scale, but also poured L66-billion-m3 sediment combined with offscourings and rubble into the Yangtze River and its breaches. This amount of sediments is 3 times more than the normal amount discharged into the Yangtze River, and will significantly increase sediment transportation of rivers and decrease storage capacities of reservoirs downstream. The dramatic increase in sediment load will imperil the engineering safety and impact the operation of the giant Three-Gorge Hydro-power Station if no proper prevention measures are taken.

Zonal Differences in Correlation Patterns Between Soil Organic Carbon and Climate Factors at Multi-extent

Studying the relationship between climate factors and soil organic carbon （SOC） is vitally important. However, how SOC responses to climate （temperature and precipitation） at cohesive extents is poorly studied. Two transects of approximately the same length （transect P and transect T） were selected to examine the variation of SOC content in relation to mean annual temperature （MAT） and mean annual precipitation （MAP）. The coefficients of partial correlation between SOC density and MAT （Rt） and MAP （Rp） were determined to quantify the relationships between SOC density and the two climate factors. The results indicated that for transect T, Rt was statistically significant once the extent level was greater than or equal to two fundamental extent units, while for transect P, Rp showed statistical significance only at extent levels which were greater than two fundamental extent traits. At the same extent levels but in different transects, Rts exhibited no zonal difference, but Rps did once the extent level was greater than two fundamental extent units. Therefore, to study the relationship between SOC density and different climate factors, different minimum extent levels should be ex- amined. The results of this paper could deepen the understanding of the impacts that SOC pool has on terrestrial ecosystem and global carbon cycling.

Generation and analysis of 113 adult stage Schistosoma japonicum (Chinese strain) expressed sequence tags

OBJECTIVE: To rapidly and economically obtain knowledge about adult stage Schistosoma japonicum (Chinese strain) expressed genes using expressed sequence tag (EST). METHODS: A directional cDNA library constructed from Schistosoma japonicum (Chinese strain) adult stage RNA was used to generate expressed sequence tags (ESTs). These were compared against an EMBL-parasites database and GENBANK database by BLASTn and BLASTx. RESULTS: A total of 314 phage clones were randomly selected for generating expressed sequence tags (ESTs). From these clones, 132 EST-quality sequence were obtained. Among these EST-quality sequences, 113 ESTs were successfully submitted to the dbEST at GenBanK. A total of 7.6% of these EST-quality sequences were previously identified sequence of Schistosoma japonicum, while 4.5% were putatively identified sequences of Schistosoma japonicum. A total of 23.5% of these EST-quality sequences were putatively identified sequence of Schistosoma mansoni or other organisms. 57.6% had no matches in the database and were classified as unknown sequences. Most ESTs with the putative protein identified belonged to housekeeping proteins. Information about several interesting genes was found. CONCLUSION: Partial cDNA sequencing to generate expressed sequence tags (ESTs) has the potential to rapidly and economically increase our knowledge about adult stage Schistosoma japonicum (Chinese strain) expressed genes.

Generation and analysis of 113 adult stage Schistosoma japonicum (Chinese strain) expressed sequence tags

To rapidly and economically obtain knowledge about adult stage Schistosoma japonicum (Chinese strain) expressed genes using expressed sequence tag (EST) Methods A directional cDNA library constructed from Schistosoma japonicum (Chinese strain ) adult stage RNA was used to generate expressed sequence tags(ESTs) These were compared against an EMBL parasites database and GENBANK database by BLASTn and BLASTx Results A total of 314 phage clones were randomly selected for generating expressed sequence tags(ESTs) From these clones, 132 EST quality sequence were obtained Among these EST quality sequences,113 ESTs were successfully submitted to the dbEST at GenBanK A total of 7 6% of these EST quality sequences were previously identified sequence of Schistosoma japonicum, while 4 5% were putatively identified sequences of Schistosoma japonicum A total of 23 5% of these EST quality sequences were putatively identified sequence of Schistosoma mansoni or other organisms 57 6% had no matches in the database and were classified as unknown sequences Most ESTs with the putative protein identified belonged to housekeeping proteins Information about several interesting genes was found Conclusion Partial cDNA sequencing to generate expressed sequence tags (ESTs) has the potential to rapidly and economically increase our knowledge about adult stage Schistosoma japonicum(Chinese strain) expressed genes

First report of brachiopods with soft parts from the Lower Cambrian Latham Shale (Series 2, Stage 4), California

Exceptionally preserved faunas have greatly improved our understanding of animal origin and evolution,and systematic investigations of Cambrian sediments around the world during the last two decades have led to a dramatic increase in the num-bers of Konservat-Lagerstatten[1].