To study the effect of thinning intensity on the carbon sequestration by natural mixed coniferous and broad-leaf forests in Xiaoxing’an Mountains,China,we established six 100 m×100 m experimental plots in Dongfa...To study the effect of thinning intensity on the carbon sequestration by natural mixed coniferous and broad-leaf forests in Xiaoxing’an Mountains,China,we established six 100 m×100 m experimental plots in Dongfanghong For-est that varied in thinning intensity:plot A(10%),B(15%),C(20%),D(25%),E(30%),F(35%),and the control sample area(0%).A principal component analysis was performed using 50 different variables,including species diversity,soil fertility,litter characteristics,canopy structure param-eters,and seedling regeneration parameters.The effects of thinning intensity on carbon sequestration were strongest in plot E(0.75),followed by D(0.63),F(0.50),C(0.48),B(0.22),A(0.11),and the control(0.06).The composite score of plot E was the highest,indicating that the carbon sequestration effect was strongest at a thinning intensity of 30%.These findings provide useful insights that could aid the management of natural mixed coniferous and broadleaf forests in Xiaoxing’an Mountains,China.This information has implications for future studies of these forests,and the methods used could aid future ecological assessments of the natural forests in Xiaoxing’an Mountains,China.展开更多
The ornamental characters, nutritious composition, edible value and medical value of thirteen kinds of major wild fruit resources in Xiaoxing’an Mountains Region were synthetically analyzed such as Rosa spp,, Actinid...The ornamental characters, nutritious composition, edible value and medical value of thirteen kinds of major wild fruit resources in Xiaoxing’an Mountains Region were synthetically analyzed such as Rosa spp,, Actinidia spp. and so on. The results showed that the wild fruit resources in this region had important garden ornamental value, edible value and medical value. A lot of good germplasm resources and honey plant resources hadnt been effectvely protected and enough utilized. The right way of appropriate arrangement and reasonable exploitation of wild fruit resources in this region should be benefit to got rid of economic crisis early in this region.展开更多
Wetlands play an important role in the global carbon cycle, but there are still considerable uncertainties in the estimation of wetland carbon storage and a dispute on whether wetlands are carbon sources or carbon sin...Wetlands play an important role in the global carbon cycle, but there are still considerable uncertainties in the estimation of wetland carbon storage and a dispute on whether wetlands are carbon sources or carbon sinks. Xiaoxing’anling are one of several concentrated distribution areas of forested wetland in China, but the carbon storage and carbon sink/source of forested wetlands in this area is unclear. We measured the ecosystem carbon storage (vegetation and soil), annual net carbon sequestration of vegetation and annual carbon emissions of soil heterotrophic respiration of five typical forested wetland types (alder swamp, white birch swamp, larch swamp, larch fen, and larch bog) distributed along a moisture gradient in this area in order to reveal the spatial variations of their carbon storage and quantitatively evaluate their position as carbon sink or source according to the net carbon balance of the ecosystems. The results show that the larch fen had high carbon storage (448.8 t ha^(−1)) (6.8% higher than the larch bog and 10.5–30.1% significantly higher than other three wetlands (P < 0.05), the white birch swamp and larch bog were medium carbon storage ecosystems (406.3 and 420.1 t ha^(−1)) (12.4–21.8% significantly higher than the other two types (P < 0.0 5), while the alder swamp and larch swamp were low in carbon storage (345.0 and 361.5 t ha^(−1), respectively). The carbon pools of the five wetlands were dominated by their soil carbon pools (88.5–94.5%), and the vegetation carbon pool was secondary (5.5–11.5%). At the same time, their ecosystem net carbon balances were positive (0.1–0.6 t ha^(−1) a^(−1)) because the annual net carbon sequestration of vegetation (4.0–4.5 t ha^(−1) a^(−1)) were higher than the annual carbon emissions of soil heterotrophic respiration (CO_(2) and CH_(4)) (3.8–4.4 t ha^(−1) a^(−1)) in four wetlands, (the alder swamp being the exception), so all four were carbon sinks while only the alder swamp was a source of carbon emissions (− 2.1 t ha^(−1) a^(−1)) due to a degraded tree layer. Our results demonstrate that these forested wetlands were generally carbon sinks in the Xiaoxing’anling, and there was obvious spatial variation in carbon storage of ecosystems along the moisture gradient.展开更多
We selected 18 rotten and nine healthy post- mature live standing Korean pine （Pinus koraiensis） to study the correlation between the degree of tree decay and soil physical-chemical properties in the Dialing Forest ...We selected 18 rotten and nine healthy post- mature live standing Korean pine （Pinus koraiensis） to study the correlation between the degree of tree decay and soil physical-chemical properties in the Dialing Forest District of the Xiaoxing＇an Mountains, China. One trans- verse section of each sample tree at 40-50 cm height above the ground was tested by Resistograph to determine the inner decay status. We collected soil samples around the root zones （6-20 cm depth） of each sample tree to test the soil physical-chemical indicators including moisture con- tent, bulk density, total porosity, pH, organic matter con- tent, total and hydrolyzed N contents, total and available P contents, total and available K contents, and C/N ratio. The degree of decay of postmature Korean pine live standing trees was significantly and positively correlated with the C/N ratio （R = 0.838, P 〈 0.05）, organic matter （R = 0.615, P = 0.007） and moisture content （R = 0.543, P = 0.020） of soil around the rodt. The contents of total N, hydrolyzed N and available P sample trees were significantly in the soil under healthy greater than those underdecayed sample trees, and larger N and P contents might inhibit the decay fungi breeding in soils of pH 4.4-6.29. The optimum multiple regression equation for degree of tree decay on soil physical-chemical indicators showed that the linear correlations between the degree of decay and soil C/N ratio and pH were significant （P 〈 0.01） and the correlation was high （R2 = 0.778）. Enhancement soil C/N ratio and pH could promote the decay of tree trunks.展开更多
Using static chamber gas chromatography, we determined the seasonal dynamics, controlling factors, and distribution patterns of forest swamp CH4 levels and related environmental factors (temperature, water level) afte...Using static chamber gas chromatography, we determined the seasonal dynamics, controlling factors, and distribution patterns of forest swamp CH4 levels and related environmental factors (temperature, water level) after fire disturbance in the Xiaoxing’an Mountains. The results showed the following: during the growing season, the annual CH4 emission distribution ranged from - 0.001 ± 0.012 to 22.373 ± 3.650 mg m^-2 h^-1;mild fire caused the swamp CH4 emission flux of tussock, shrub, Alnus sibirica and birch swamp to increase by 56.0–524.7%;at low water levels, temperature had a significant influence on the swamp type, and the correlation between the methane emission flux and temperature was significantly strengthened;after a fire disturbance, methane emissions from all types of marsh were highest in summer and second highest in autumn, with a weak absorption in spring;and along the water environment gradient of the transition zone, the CH4 emission flux presented a decreasing trend in its spatial distribution pattern.展开更多
基金funded by National Key Research and development project(2022YFD2201001)Project for Applied TechnologyResearch and Development in Heilongjiang Province(GA19C006).
文摘To study the effect of thinning intensity on the carbon sequestration by natural mixed coniferous and broad-leaf forests in Xiaoxing’an Mountains,China,we established six 100 m×100 m experimental plots in Dongfanghong For-est that varied in thinning intensity:plot A(10%),B(15%),C(20%),D(25%),E(30%),F(35%),and the control sample area(0%).A principal component analysis was performed using 50 different variables,including species diversity,soil fertility,litter characteristics,canopy structure param-eters,and seedling regeneration parameters.The effects of thinning intensity on carbon sequestration were strongest in plot E(0.75),followed by D(0.63),F(0.50),C(0.48),B(0.22),A(0.11),and the control(0.06).The composite score of plot E was the highest,indicating that the carbon sequestration effect was strongest at a thinning intensity of 30%.These findings provide useful insights that could aid the management of natural mixed coniferous and broadleaf forests in Xiaoxing’an Mountains,China.This information has implications for future studies of these forests,and the methods used could aid future ecological assessments of the natural forests in Xiaoxing’an Mountains,China.
文摘The ornamental characters, nutritious composition, edible value and medical value of thirteen kinds of major wild fruit resources in Xiaoxing’an Mountains Region were synthetically analyzed such as Rosa spp,, Actinidia spp. and so on. The results showed that the wild fruit resources in this region had important garden ornamental value, edible value and medical value. A lot of good germplasm resources and honey plant resources hadnt been effectvely protected and enough utilized. The right way of appropriate arrangement and reasonable exploitation of wild fruit resources in this region should be benefit to got rid of economic crisis early in this region.
基金This project was supported fi nancially by the National Key Research and Development Program of China(2016YFA0600803)the National Natural Science Foundation of China(31370461).
文摘Wetlands play an important role in the global carbon cycle, but there are still considerable uncertainties in the estimation of wetland carbon storage and a dispute on whether wetlands are carbon sources or carbon sinks. Xiaoxing’anling are one of several concentrated distribution areas of forested wetland in China, but the carbon storage and carbon sink/source of forested wetlands in this area is unclear. We measured the ecosystem carbon storage (vegetation and soil), annual net carbon sequestration of vegetation and annual carbon emissions of soil heterotrophic respiration of five typical forested wetland types (alder swamp, white birch swamp, larch swamp, larch fen, and larch bog) distributed along a moisture gradient in this area in order to reveal the spatial variations of their carbon storage and quantitatively evaluate their position as carbon sink or source according to the net carbon balance of the ecosystems. The results show that the larch fen had high carbon storage (448.8 t ha^(−1)) (6.8% higher than the larch bog and 10.5–30.1% significantly higher than other three wetlands (P < 0.05), the white birch swamp and larch bog were medium carbon storage ecosystems (406.3 and 420.1 t ha^(−1)) (12.4–21.8% significantly higher than the other two types (P < 0.0 5), while the alder swamp and larch swamp were low in carbon storage (345.0 and 361.5 t ha^(−1), respectively). The carbon pools of the five wetlands were dominated by their soil carbon pools (88.5–94.5%), and the vegetation carbon pool was secondary (5.5–11.5%). At the same time, their ecosystem net carbon balances were positive (0.1–0.6 t ha^(−1) a^(−1)) because the annual net carbon sequestration of vegetation (4.0–4.5 t ha^(−1) a^(−1)) were higher than the annual carbon emissions of soil heterotrophic respiration (CO_(2) and CH_(4)) (3.8–4.4 t ha^(−1) a^(−1)) in four wetlands, (the alder swamp being the exception), so all four were carbon sinks while only the alder swamp was a source of carbon emissions (− 2.1 t ha^(−1) a^(−1)) due to a degraded tree layer. Our results demonstrate that these forested wetlands were generally carbon sinks in the Xiaoxing’anling, and there was obvious spatial variation in carbon storage of ecosystems along the moisture gradient.
基金financially supported by the Introduction Program of New Tech from Overseas(20140478)the Forestry Nonprofit Special Research Project(201104007)
文摘We selected 18 rotten and nine healthy post- mature live standing Korean pine （Pinus koraiensis） to study the correlation between the degree of tree decay and soil physical-chemical properties in the Dialing Forest District of the Xiaoxing＇an Mountains, China. One trans- verse section of each sample tree at 40-50 cm height above the ground was tested by Resistograph to determine the inner decay status. We collected soil samples around the root zones （6-20 cm depth） of each sample tree to test the soil physical-chemical indicators including moisture con- tent, bulk density, total porosity, pH, organic matter con- tent, total and hydrolyzed N contents, total and available P contents, total and available K contents, and C/N ratio. The degree of decay of postmature Korean pine live standing trees was significantly and positively correlated with the C/N ratio （R = 0.838, P 〈 0.05）, organic matter （R = 0.615, P = 0.007） and moisture content （R = 0.543, P = 0.020） of soil around the rodt. The contents of total N, hydrolyzed N and available P sample trees were significantly in the soil under healthy greater than those underdecayed sample trees, and larger N and P contents might inhibit the decay fungi breeding in soils of pH 4.4-6.29. The optimum multiple regression equation for degree of tree decay on soil physical-chemical indicators showed that the linear correlations between the degree of decay and soil C/N ratio and pH were significant （P 〈 0.01） and the correlation was high （R2 = 0.778）. Enhancement soil C/N ratio and pH could promote the decay of tree trunks.
基金supported by postdoctoral grant of HeiLongJiang(Grant No.LBH-Z17002)
文摘Using static chamber gas chromatography, we determined the seasonal dynamics, controlling factors, and distribution patterns of forest swamp CH4 levels and related environmental factors (temperature, water level) after fire disturbance in the Xiaoxing’an Mountains. The results showed the following: during the growing season, the annual CH4 emission distribution ranged from - 0.001 ± 0.012 to 22.373 ± 3.650 mg m^-2 h^-1;mild fire caused the swamp CH4 emission flux of tussock, shrub, Alnus sibirica and birch swamp to increase by 56.0–524.7%;at low water levels, temperature had a significant influence on the swamp type, and the correlation between the methane emission flux and temperature was significantly strengthened;after a fire disturbance, methane emissions from all types of marsh were highest in summer and second highest in autumn, with a weak absorption in spring;and along the water environment gradient of the transition zone, the CH4 emission flux presented a decreasing trend in its spatial distribution pattern.
