CH4 is one of the most important greenhouse gases, and mainly comes from soils in forest ecosystems. The objective of this study was to determine the effects of forest management practices such as understory removal a...CH4 is one of the most important greenhouse gases, and mainly comes from soils in forest ecosystems. The objective of this study was to determine the effects of forest management practices such as understory removal and N-fixing species （Cassia alata） addition, on soil CH4 fluxes in four forest plantations in southern China. Fluxes of CH4 were measured in Eucalyptus urophylla plantation （B1）, Acacia crassi-carpa plantation （B2）, 10-native-species-mixed plantation （B3）, and 30-native-species-mixed plantation （B4） stands using the static chamber method in Southern China. Four forest management treatments, includ-ing （1） understory removal and replacement with C. alata （UR＋CA）; （2） understory removal only （UR）; （3） C. alata addition only （CA）; and （4） control without any disturbances （CK）, were applied in the four forest plantations. The results showed that plantation types had a significant effect on soil CH4 fluxes. B1 and B2 tended to be CH4 consumers, while B3 and B4 inclined to be CH4 producers. UR decreased CH4 fluxes by providing a more optimal soil temperature and moisture regime for mi-croorganism community and increasing substrate mineralization. How-ever, CA enhanced CH4 fluxes in B1 and B2 for N-fixing function of C. alata while lowered CH4 fluxes in B3 and B4. Soil CH4 flux rate was significantly related to soil temperature and moisture conditions in the top 10-cm soil layer. Furthermore, the quality of substrates, such as Soil Organic Carbon （SOC） and mineral N might also be important driving factors for CH4 fluxes. This study improved our understanding on CH4 fluxes in plantations under different management practices such as UR and CA.展开更多
The Irtysh River Basin refers to a water conservation area and a vital ecological barrier in Xinjiang and also partially in Central Asia.Here,the technical solution for the ecological protection and the restoration of...The Irtysh River Basin refers to a water conservation area and a vital ecological barrier in Xinjiang and also partially in Central Asia.Here,the technical solution for the ecological protection and the restoration of the Mountains-Rivers-Forests-Farmlands-Lakes-Grasslands system(MRFFLGs)pilot project in the Irtysh River Basin is refined,by complying with the core concept,i.e.,"mountains,rivers,forests,farmlands,lakes and grasslands are a community of life".The solution stresses the specific characteristics of ecologically protecting and restoring MRFFLGs in the Irtysh River Basin,which aim to reduce ecological water use,soil erosion,forest and grassland degradation,the ecological destruction of mines,water environment pollution and other issues.With overall protection,system restoration,district policy,and problem orientation as the overarching ideas,162 sub-items of 44 major items with seven categories have been designed and implemented in the project.In addition,some highlights of the management experience that are worth promoting when the pilot project is being implemented are also summarized(e.g.,the use of laws to solve historical problems,scientific argumentation and third-party evaluation,proactive guidance for the engagement of people,modern information technology support,and integration with local sustainable development).Lastly,four policy suggestions are proposed:(1)Building a model of systematic protection and restoration by using basins as the basic geographic unit;(2)Establishing and optimizing key weak links of systems and mechanisms;(3)Focusing on remedying the shortcomings of regional talents,technology and capital;and(4)Promoting the MRFFLGs project to integrate"industry,city,people,and tourism"for carrying out a large-scale system project.展开更多
基金This research was supported by the Natural Science Foundation of China (30630015, 30771704)
文摘CH4 is one of the most important greenhouse gases, and mainly comes from soils in forest ecosystems. The objective of this study was to determine the effects of forest management practices such as understory removal and N-fixing species （Cassia alata） addition, on soil CH4 fluxes in four forest plantations in southern China. Fluxes of CH4 were measured in Eucalyptus urophylla plantation （B1）, Acacia crassi-carpa plantation （B2）, 10-native-species-mixed plantation （B3）, and 30-native-species-mixed plantation （B4） stands using the static chamber method in Southern China. Four forest management treatments, includ-ing （1） understory removal and replacement with C. alata （UR＋CA）; （2） understory removal only （UR）; （3） C. alata addition only （CA）; and （4） control without any disturbances （CK）, were applied in the four forest plantations. The results showed that plantation types had a significant effect on soil CH4 fluxes. B1 and B2 tended to be CH4 consumers, while B3 and B4 inclined to be CH4 producers. UR decreased CH4 fluxes by providing a more optimal soil temperature and moisture regime for mi-croorganism community and increasing substrate mineralization. How-ever, CA enhanced CH4 fluxes in B1 and B2 for N-fixing function of C. alata while lowered CH4 fluxes in B3 and B4. Soil CH4 flux rate was significantly related to soil temperature and moisture conditions in the top 10-cm soil layer. Furthermore, the quality of substrates, such as Soil Organic Carbon （SOC） and mineral N might also be important driving factors for CH4 fluxes. This study improved our understanding on CH4 fluxes in plantations under different management practices such as UR and CA.
基金The Major Science and Technology Projects in Altay Region(E0035219)The National Natural Science Foundation of China(41630644+1 种基金42001139)The China Postdoctoral Science Foundation(2020M670472)。
文摘The Irtysh River Basin refers to a water conservation area and a vital ecological barrier in Xinjiang and also partially in Central Asia.Here,the technical solution for the ecological protection and the restoration of the Mountains-Rivers-Forests-Farmlands-Lakes-Grasslands system(MRFFLGs)pilot project in the Irtysh River Basin is refined,by complying with the core concept,i.e.,"mountains,rivers,forests,farmlands,lakes and grasslands are a community of life".The solution stresses the specific characteristics of ecologically protecting and restoring MRFFLGs in the Irtysh River Basin,which aim to reduce ecological water use,soil erosion,forest and grassland degradation,the ecological destruction of mines,water environment pollution and other issues.With overall protection,system restoration,district policy,and problem orientation as the overarching ideas,162 sub-items of 44 major items with seven categories have been designed and implemented in the project.In addition,some highlights of the management experience that are worth promoting when the pilot project is being implemented are also summarized(e.g.,the use of laws to solve historical problems,scientific argumentation and third-party evaluation,proactive guidance for the engagement of people,modern information technology support,and integration with local sustainable development).Lastly,four policy suggestions are proposed:(1)Building a model of systematic protection and restoration by using basins as the basic geographic unit;(2)Establishing and optimizing key weak links of systems and mechanisms;(3)Focusing on remedying the shortcomings of regional talents,technology and capital;and(4)Promoting the MRFFLGs project to integrate"industry,city,people,and tourism"for carrying out a large-scale system project.
