Seasonal dynamics of above- and belowground biomass and nutrient characteristics （nitrogen, carbon, and phosphorus） of Carex lasiocarpa were investigated in the typical wetland of Sanjiang Plain, China from May 2007...Seasonal dynamics of above- and belowground biomass and nutrient characteristics （nitrogen, carbon, and phosphorus） of Carex lasiocarpa were investigated in the typical wetland of Sanjiang Plain, China from May 2007 to September 2008. The results show that the changes of aboveground biomass during the growing season are best described by the twice function curve model, whereas the changes of belowground biomass follow the exponential increase curve model. Both the organic carbon contents in the above- and belowground plant parts show significant positive linear correlations with the growing time, and the coefficients R2 are 0.983 and 0.746, respectively. The carbon accu-mulations of the above- and belowground plant parts during the growing season show the same dynamics as those of the biomass. However, the nitrogen contents and accumulation in C. lasiocarpa aboveground and belowground parts show exponential increase during the growing season. The dynamics of C. lasiocarpa phosphorus contents follows the twice function curve model, whereas the accumulation of phosphorus shows the linear increase. The ratios of C/N in different parts of C. lasiocarpa fit the negative linear relations with total nitrogen content in the growing season. Moreover, the ratios of C/P in C. lasiocarpa plant also fit the negative linear relations with total phosphorus content. The results show that nitrogen is the primary limiting nutrient for C. lasiocarpa growth as compared with carbon and phosphorus.展开更多
The species diversity at the regeneration stage, inflenced by different water levels, is important for community composition in the later growing season.Regeneration diversity of Carex lasiocarpa community under diffe...The species diversity at the regeneration stage, inflenced by different water levels, is important for community composition in the later growing season.Regeneration diversity of Carex lasiocarpa community under different water levels was studied at two stages, recruitment and adult, in the Sanjiang Plain, Heilongjiang Province, China.The results showed that, at the two growing stages, important value of C.lasiocarpa population and species richness of the community decreased with the increasing water level, while the Simpson and Shannon-Wiener diversity indexes and Pielou evenness index increased.Under different water levels, community diversities were higher at the recruitment stage, while population important values of C.lasiocarpa were higher at the adult stage.Indexes in vegetation evaluation must be chosen prudentially for successful restoration and effective management of wetlands, and especially for wetland restoration, the optimal time should be selected according to the restoration objectives and costs.展开更多
[Objective] The morphological characters of C.lasiocarpa were studied to find its morphological responses to different water regimes and growth stretagies through different water experiences.[Method] A seeding transpl...[Objective] The morphological characters of C.lasiocarpa were studied to find its morphological responses to different water regimes and growth stretagies through different water experiences.[Method] A seeding transplanting experiment with controlled water levels was set up,and the water level was changed at the middle of the season to compare water influence at the seeding stage and later growing period.C.lasiocarpa height,leaf length,leaf number,rhizome and adventitious roots length were measured at certain time througth the growing season.[Result] Results at the thriving season indicated that C.lasiocarpa height and leaf length in the experiment were similar to that in the field,but leaf number was higher under-5 cm water level and dry-wet alternate conditions than that in the field.At later growth period,height and leaf length under constant flooding(15cm) was significantly higher than that under other culture conditions,and also that of the field investigation;while the leaf number had a trend as-5 cm water level treatment>constant flooding>dry-wet alternate>field investigation.The height and leaf length were sensitive to seeding stage water effects,and leaf number sensitive to later influences.[Conclusion] Changes of water regimes in the growing season disturbed the growth of C.lasiocarpa,could accelerate or suspend its wilt,and modified the length of life history.展开更多
基金This research was supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (No.KZCX2–YW–309)the Major State Basic Research Development Program of China (973 Program No. 2004CB418507)
文摘Seasonal dynamics of above- and belowground biomass and nutrient characteristics （nitrogen, carbon, and phosphorus） of Carex lasiocarpa were investigated in the typical wetland of Sanjiang Plain, China from May 2007 to September 2008. The results show that the changes of aboveground biomass during the growing season are best described by the twice function curve model, whereas the changes of belowground biomass follow the exponential increase curve model. Both the organic carbon contents in the above- and belowground plant parts show significant positive linear correlations with the growing time, and the coefficients R2 are 0.983 and 0.746, respectively. The carbon accu-mulations of the above- and belowground plant parts during the growing season show the same dynamics as those of the biomass. However, the nitrogen contents and accumulation in C. lasiocarpa aboveground and belowground parts show exponential increase during the growing season. The dynamics of C. lasiocarpa phosphorus contents follows the twice function curve model, whereas the accumulation of phosphorus shows the linear increase. The ratios of C/N in different parts of C. lasiocarpa fit the negative linear relations with total nitrogen content in the growing season. Moreover, the ratios of C/P in C. lasiocarpa plant also fit the negative linear relations with total phosphorus content. The results show that nitrogen is the primary limiting nutrient for C. lasiocarpa growth as compared with carbon and phosphorus.
基金Under the auspices of the National Basic Research Program of China (No. 2009CB421103)Northeast Revitalization Program,Chinese Academy of Sciences (No. DBZX-2-024)
文摘The species diversity at the regeneration stage, inflenced by different water levels, is important for community composition in the later growing season.Regeneration diversity of Carex lasiocarpa community under different water levels was studied at two stages, recruitment and adult, in the Sanjiang Plain, Heilongjiang Province, China.The results showed that, at the two growing stages, important value of C.lasiocarpa population and species richness of the community decreased with the increasing water level, while the Simpson and Shannon-Wiener diversity indexes and Pielou evenness index increased.Under different water levels, community diversities were higher at the recruitment stage, while population important values of C.lasiocarpa were higher at the adult stage.Indexes in vegetation evaluation must be chosen prudentially for successful restoration and effective management of wetlands, and especially for wetland restoration, the optimal time should be selected according to the restoration objectives and costs.
基金Supported by the National Natural Science Foundation of China(41001030)the Natural Science Basic Research Plan in Shaanxi Province of China(2014JQ5194,2014JM7206)+1 种基金the Education Department of Shaanxi Province Special Research Project(12JK048415JK1386)
文摘[Objective] The morphological characters of C.lasiocarpa were studied to find its morphological responses to different water regimes and growth stretagies through different water experiences.[Method] A seeding transplanting experiment with controlled water levels was set up,and the water level was changed at the middle of the season to compare water influence at the seeding stage and later growing period.C.lasiocarpa height,leaf length,leaf number,rhizome and adventitious roots length were measured at certain time througth the growing season.[Result] Results at the thriving season indicated that C.lasiocarpa height and leaf length in the experiment were similar to that in the field,but leaf number was higher under-5 cm water level and dry-wet alternate conditions than that in the field.At later growth period,height and leaf length under constant flooding(15cm) was significantly higher than that under other culture conditions,and also that of the field investigation;while the leaf number had a trend as-5 cm water level treatment>constant flooding>dry-wet alternate>field investigation.The height and leaf length were sensitive to seeding stage water effects,and leaf number sensitive to later influences.[Conclusion] Changes of water regimes in the growing season disturbed the growth of C.lasiocarpa,could accelerate or suspend its wilt,and modified the length of life history.
