Application of China's National Forest Continuous Inventory database.

The maintenance of a timely, reliable and accurate spatial database on current forest ecosystem conditions and changes is essential to characterize and assess forest resources and support sustainable forest management. Information for such a database can be obtained only through a continuous forest inventory. The National Forest Continuous Inventory (NFCI) is the first level of China's three-tiered inventory system. The NFCI is administered by the State Forestry Administration; data are acquired by five inventory institutions around the country. Several important components of the database include land type, forest classification and ageclass/ age-group. The NFCI database in China is constructed based on 5-year inventory periods, resulting in some of the data not being timely when reports are issued. To address this problem, a forest growth simulation model has been developed to update the database for years between the periodic inventories. In order to aid in forest plan design and management, a three-dimensional virtual reality system of forest landscapes for selected units in the database (compartment or sub-compartment) has also been developed based on Virtual Reality Modeling Language. In addition, a transparent internet publishing system for a spatial database based on open source WebGIS (UMN Map Server) has been designed and utilized to enhance public understanding and encourage free participation of interested parties in the development, implementation, and planning of sustainable forest management.

Spatial, sources and risk assessment of heavy metal contamination of urban soils in typical regions of Shenyang, China.

Surface soil samples from 36 sampling sites including different functional areas in seven districts of Shenyang, China were collected and analyzed. The results showed that the average concentrations of Cd, Cu, Pb and Zn in soil of Shenyang were up to 0.42, 51.26, 75.29 and 140.02mg/kg, respectively, which are much higher than their natural background values. Among the functional areas and administrative regions, the industrial regions and the Tiexi District displayed the highest metal concentrations. Pearson's correlation analysis showed that there existed close correlations among Cd, Cu, Pb and Zn (except for Cd-Cu) at 1% level. Principal Component Analysis (PCA) coupled with correlation between heavy metals revealed that heavy metal contamination might originate from traffic and industrial activities. The values of pollution index (PI) and integrated pollution index (IPI) indicated that metal pollution level was Pb>Cd>Zn>Cu, and Cd, Cu, Pb and Zn belong to moderate or high pollution level. Potential ecological risk indexes (RI) further indicated that Shenyang was suffering from serious metal contamination. These results are important for the development of proper management strategies to decrease non-point source pollution by various remediation practices in Shenyang, China.