Net primary productivity(NPP), a metric used to define and identify changes in plant communities, is greatly affected by climate change, human activities and other factors. Here, we used the Carnegie-Ames-Stanford App...Net primary productivity(NPP), a metric used to define and identify changes in plant communities, is greatly affected by climate change, human activities and other factors. Here, we used the Carnegie-Ames-Stanford Approach(CASA) model to estimate the NPP of plant communities in Hengduan Mountains area of China, and to explore the relationship between NPP and altitude in this region. We examined the mechanisms underlying vegetation growth responses to climate change and quantitatively assessed the effects of ecological protection measures by partitioning the contributions of climate change and human activities to NPP changes. The results demonstrated that: 1) the average total and annual NPP values over the years were 209.15 Tg C and 468.06 g C/(m2·yr), respectively. Their trend increasingly fluctuated, with spatial distribution strongly linked to altitude(i.e., lower and higher NPP in high altitude and low altitude areas, respectively) and 2400 m represented the marginal altitude for vegetation differentiation; 2) areas where climate was the main factor affecting NPP accounted for 18.2% of the total research area, whereas human activities were the primary factor influencing NPP in 81.8% of the total research area, which indicated that human activity was the main force driving changes in NPP. Areas where climatic factors(i.e., temperature and precipitation) were the main driving factors occupied 13.6%(temperature) and 6.0%(precipitation) of the total research area, respectively. Therefore, the effect of temperature on NPP changes was stronger than that of precipitation; and 3) the majority of NPP residuals from 2001 to 2014 were positive, with human activities playing an active role in determining regional vegetation growth, possibly due to the return of farmland back to forest and natural forest protection. However, this positive trend is decreasing. This clearly shows the periodical nature of ecological projects and a lack of long-term effectiveness.展开更多
Key Biodiversity Areas(KBAs)are ecological conservation priorities proposed by IUCN and widely recognized by most countries.Evaluating the changes in the ecological characteristics in KBAs is important for biodiversit...Key Biodiversity Areas(KBAs)are ecological conservation priorities proposed by IUCN and widely recognized by most countries.Evaluating the changes in the ecological characteristics in KBAs is important for biodiversity conservation and the construction of Protected Areas(PAs).There are various ecosystem types in the Belt and Road Initiative(BRI)region,which has an extremely high value of biodiversity conservation,and the KBAs should be the prime targets of ecological protection efforts.Using the data of land cover,NDVI and Nighttime Light(NTL),we analyzed the ecological conditions of the KBAs in the BRI region,and their temporal and spatial variations,from the perspectives of vegetation coverage and human activities.The conclusions are:(1)There is generally no significant difference in the land cover of the KBAs,among which forest,wilderness and grassland are the main types;(2)The NDVI of the KBAs showed an increase,indicating that the vegetation was gradually improving,while a few KBAs presenting vegetation degradation were mainly distributed in the Indochina Peninsula,Qinghai-Tibet Plateau and Central and Western Asia;and(3)The NTL in the KBAs was very low,indicating that the human pressure on the natural ecosystems was limited,and only a few KBAs distributed in Central and Eastern Europe,India,and the Indochina Peninsula have high human activity intensity which also showed an increase.This study emphasizes that we should make full use of the biome succession law,and limit the interference of human activities on natural ecosystems for ecological protection of the KBAs,so as to continuously make new breakthroughs in the construction of Protected Areas(PA)in the BRI region.展开更多
基金Under the auspices of National Key Basic Research Program of China(No.2015CB452706)National Natural Science Foundation of China(No.41401198,41571527)+1 种基金Youth Talent Team Program of the Institute of Mountain Hazards and Environment,Chinese Academy of Sciences(No.SDSQB-2015-01)Youth Innovation Promotion Association,Chinese Academy of Sciences(No.2016332)
文摘Net primary productivity(NPP), a metric used to define and identify changes in plant communities, is greatly affected by climate change, human activities and other factors. Here, we used the Carnegie-Ames-Stanford Approach(CASA) model to estimate the NPP of plant communities in Hengduan Mountains area of China, and to explore the relationship between NPP and altitude in this region. We examined the mechanisms underlying vegetation growth responses to climate change and quantitatively assessed the effects of ecological protection measures by partitioning the contributions of climate change and human activities to NPP changes. The results demonstrated that: 1) the average total and annual NPP values over the years were 209.15 Tg C and 468.06 g C/(m2·yr), respectively. Their trend increasingly fluctuated, with spatial distribution strongly linked to altitude(i.e., lower and higher NPP in high altitude and low altitude areas, respectively) and 2400 m represented the marginal altitude for vegetation differentiation; 2) areas where climate was the main factor affecting NPP accounted for 18.2% of the total research area, whereas human activities were the primary factor influencing NPP in 81.8% of the total research area, which indicated that human activity was the main force driving changes in NPP. Areas where climatic factors(i.e., temperature and precipitation) were the main driving factors occupied 13.6%(temperature) and 6.0%(precipitation) of the total research area, respectively. Therefore, the effect of temperature on NPP changes was stronger than that of precipitation; and 3) the majority of NPP residuals from 2001 to 2014 were positive, with human activities playing an active role in determining regional vegetation growth, possibly due to the return of farmland back to forest and natural forest protection. However, this positive trend is decreasing. This clearly shows the periodical nature of ecological projects and a lack of long-term effectiveness.
基金The Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20010202)The National Key Research and Development Program of China(2016YFC0503505)。
文摘Key Biodiversity Areas(KBAs)are ecological conservation priorities proposed by IUCN and widely recognized by most countries.Evaluating the changes in the ecological characteristics in KBAs is important for biodiversity conservation and the construction of Protected Areas(PAs).There are various ecosystem types in the Belt and Road Initiative(BRI)region,which has an extremely high value of biodiversity conservation,and the KBAs should be the prime targets of ecological protection efforts.Using the data of land cover,NDVI and Nighttime Light(NTL),we analyzed the ecological conditions of the KBAs in the BRI region,and their temporal and spatial variations,from the perspectives of vegetation coverage and human activities.The conclusions are:(1)There is generally no significant difference in the land cover of the KBAs,among which forest,wilderness and grassland are the main types;(2)The NDVI of the KBAs showed an increase,indicating that the vegetation was gradually improving,while a few KBAs presenting vegetation degradation were mainly distributed in the Indochina Peninsula,Qinghai-Tibet Plateau and Central and Western Asia;and(3)The NTL in the KBAs was very low,indicating that the human pressure on the natural ecosystems was limited,and only a few KBAs distributed in Central and Eastern Europe,India,and the Indochina Peninsula have high human activity intensity which also showed an increase.This study emphasizes that we should make full use of the biome succession law,and limit the interference of human activities on natural ecosystems for ecological protection of the KBAs,so as to continuously make new breakthroughs in the construction of Protected Areas(PA)in the BRI region.
