For understanding the reasons that caused the degradation of water quality in lower order streams, systematic sampling was conducted at different spatial locations aiong the low order streams （1 st-5th） of Ashihe Ri...For understanding the reasons that caused the degradation of water quality in lower order streams, systematic sampling was conducted at different spatial locations aiong the low order streams （1 st-5th） of Ashihe River continuum in Maoershan Experimental Forest of Northeast Forestry University, Sharlgzhi City, Heilongjiang Province, China. The indexes of stream water quality, i.e., the pH, dissolved oxygen（DO）, turbidity, temperature, PO43-P, NO3-N and NH4^＋-N concentrations, total dissolved inorganic nitrogen （TDIN-N, including concentrations of NO3^＋-N and NH4^＋-N）, and total phosphorus （inorganic and organic phosphorous, TP） were measured and analyzed. The stream order, related environmental settings and land-use type were recorded for each sampling location. The indexes of stream water quality at different locations with different stream orders and land use types were compared by ANOVA analysis. The indexes of stream water quality at different sampling locations were analyzed by Hierarchical cluster analysis. Result showed that water quality had significant difference in different stream orders and land use types; some locations with different stream features （stream order and land use type） were grouped into same clusters, indicating that random disturbances produced the variations in water quality, which made the spatial variances of stream water quality inconsistent with the general rules.展开更多
Fire is quite a common natural phenomenon closely related to forest hydrology in forest ecosystem. The influence of fire on water is indirectly manifested in that the post fire changes of vegetation, ground cover, soi...Fire is quite a common natural phenomenon closely related to forest hydrology in forest ecosystem. The influence of fire on water is indirectly manifested in that the post fire changes of vegetation, ground cover, soil and environment affect water cycle, water quality and aquatic lives. The effect varies depending upon fire severity and frequency. Light wildland fires or prescribed burnings do not affect hydrology regime significantly but frequent burnings or intense fires can cause changes in hydrology regime similar to that caused clear cutting.展开更多
Chinese Forest Ecosystem Research Network, established in late 1950s and directly constructedand administered by the Science and Technology Department of State Forestry Administration of China,is a large ecology resea...Chinese Forest Ecosystem Research Network, established in late 1950s and directly constructedand administered by the Science and Technology Department of State Forestry Administration of China,is a large ecology research network focuses on long-term ecosystem fixed-observation. It embodies 15 sitesthat represent diverse ecosystems and research priorities, including 6 state-level sites. CFERN Officecoordinates communications, network publications, and research-planning activities. CFERN uses theadvanced ground and spatial observation technologies such as RS, GPS, GIS to study the structure,functional laws and feedback mechanism of Chinese forest ecosystem, as well as its effects on Chinassocial and economic development. The main tasks carried out by CFERN are: (1) construction of thedatabase on the structure and functions of Chinese forest ecosystem and its ecological environmentalfactors; (2) the database construction of forest resources, ecological environment, water resources andrelated social economy in both regional and national scales; (3) the establishment of an evaluation systemof forest ecological effects in Chinas main drainage areas; (4) the establishment of a forest environmentmonitoring network and a dynamic prediction and alarm system.展开更多
基金This research was supported by a grant of the National Nature Science Foundation of China （No. 30370277）.
文摘For understanding the reasons that caused the degradation of water quality in lower order streams, systematic sampling was conducted at different spatial locations aiong the low order streams （1 st-5th） of Ashihe River continuum in Maoershan Experimental Forest of Northeast Forestry University, Sharlgzhi City, Heilongjiang Province, China. The indexes of stream water quality, i.e., the pH, dissolved oxygen（DO）, turbidity, temperature, PO43-P, NO3-N and NH4^＋-N concentrations, total dissolved inorganic nitrogen （TDIN-N, including concentrations of NO3^＋-N and NH4^＋-N）, and total phosphorus （inorganic and organic phosphorous, TP） were measured and analyzed. The stream order, related environmental settings and land-use type were recorded for each sampling location. The indexes of stream water quality at different locations with different stream orders and land use types were compared by ANOVA analysis. The indexes of stream water quality at different sampling locations were analyzed by Hierarchical cluster analysis. Result showed that water quality had significant difference in different stream orders and land use types; some locations with different stream features （stream order and land use type） were grouped into same clusters, indicating that random disturbances produced the variations in water quality, which made the spatial variances of stream water quality inconsistent with the general rules.
文摘Fire is quite a common natural phenomenon closely related to forest hydrology in forest ecosystem. The influence of fire on water is indirectly manifested in that the post fire changes of vegetation, ground cover, soil and environment affect water cycle, water quality and aquatic lives. The effect varies depending upon fire severity and frequency. Light wildland fires or prescribed burnings do not affect hydrology regime significantly but frequent burnings or intense fires can cause changes in hydrology regime similar to that caused clear cutting.
文摘Chinese Forest Ecosystem Research Network, established in late 1950s and directly constructedand administered by the Science and Technology Department of State Forestry Administration of China,is a large ecology research network focuses on long-term ecosystem fixed-observation. It embodies 15 sitesthat represent diverse ecosystems and research priorities, including 6 state-level sites. CFERN Officecoordinates communications, network publications, and research-planning activities. CFERN uses theadvanced ground and spatial observation technologies such as RS, GPS, GIS to study the structure,functional laws and feedback mechanism of Chinese forest ecosystem, as well as its effects on Chinassocial and economic development. The main tasks carried out by CFERN are: (1) construction of thedatabase on the structure and functions of Chinese forest ecosystem and its ecological environmentalfactors; (2) the database construction of forest resources, ecological environment, water resources andrelated social economy in both regional and national scales; (3) the establishment of an evaluation systemof forest ecological effects in Chinas main drainage areas; (4) the establishment of a forest environmentmonitoring network and a dynamic prediction and alarm system.
