A study was conducted to examine the distribution pattern of four rhizomatous medicinal and aromatic plant species （MAPs） viz., Angelica glauca, Pleurospermum angelicoides, Rheum emodi and Arne- bia benthamii in dif...A study was conducted to examine the distribution pattern of four rhizomatous medicinal and aromatic plant species （MAPs） viz., Angelica glauca, Pleurospermum angelicoides, Rheum emodi and Arne- bia benthamii in different forest stands in Central Himalaya. Results show that A. glauca and P. angelicoides had a higher （50%） frequency at Chipkoan, Garpak and Phagati forest, R. emodi had a higher （60%） frequency at Rishikund, Suki and Himtoli, and A. benthamii had a higher （70%） frequency at Suki and Khambdhar The densities of A. glauca （0.6 plants·m -2 ） and P. angelicoides （0.5 plants·m -2 ） were higher at Chipkoan and Garpak sites than at other micro-sites, while densities of R. emodi （0.8 plants·m -2 ） and A. benthamii （1.0 plants·m -2 ） were higher at Suki and Khambdhar sites. A. glauca had highest total basal covers （TBC） （1.2 cm 2 ·m -2 ） at Chipkoan, P. angelicoides had highest TBC （0.92 cm 2 ·m -2） at Lati kharak site, A. benthamii had the highest TBC （6.48 cm 2 ·m -2 ） atKhambdhar, and R. emodi had highest TBC （4.53 cm 2 ·m -2 ） at Rishikund. For the four studied species, A. glauca showed a contagious distribution, P. angelicoides and R. emodi showed the random and A. benthamii showed the regular type of distribution.展开更多
The geology and geomorphology of the territory as well as microclimate are local geographical features that serve as natural ecological resources. These factors influence the biosynthetic activities of plants and thei...The geology and geomorphology of the territory as well as microclimate are local geographical features that serve as natural ecological resources. These factors influence the biosynthetic activities of plants and their phenology, promoting biodiversity and the qualitative predispositions of grapes and wine. South Tyrol is one of the smallest wine-growing regions in Italy, but owing to its position amid the Alps, it is also one of the most multifaceted, a region of wide geographical diversity and remarkable ecological range, hosting a concentration of many different vine varieties and high quality wines. This applied territorial research investigates the particular environmental circumstances that favour this case. A data set describing approximately 26,000 vineyards and 5450 hectares has been employed to evaluate 18 subzones of wines and vines selected from 86 new geographical units defined within the DOC wine region. A new environmental mapping scheme called VHTG is proposed, based on the ecological indicators of grape variety, altitude, topoclimate and the geopedology of the vineyards. Using the VHTG method analyses, the comparisons between the territories of origin and their vine varieties can be rendered simpler and more direct, and it can distinguish the most suitable ecological conditions of wine production zones. It is now possible to examine more in detail the land suitability of the different cultivars, defined by the use of the ecological indicators summarized in the VHTG method. White grape varieties such as Sylvaner and Veltliner prefer high altitudes between 600 m and 900 m, a very high solar radiation SRI index from 80 to 95, and acidic sandy soils of silicate minerals. The most complete and intense tannic structure of regional Pinot Noir correlates to quite clayey soils with dolomite mineral, slightly alkaline, on vineyards at altitudes between 350 m and 410 m, with rather low SRI index from 60 to 75. Similar geopedological conditions favour Gewürztraminer, which, however, requests SRI from 75 to 展开更多
高寒灌丛草甸和草甸均是青藏高原广泛分布的植被类型,在生态系统碳通量和区域碳循环中具有极其重要的作用。然而迄今为止,对其碳通量动态的时空变异还缺乏比较分析,对碳通量的季节和年际变异的主导影响因子认识还不够清晰,不利于深入理...高寒灌丛草甸和草甸均是青藏高原广泛分布的植被类型,在生态系统碳通量和区域碳循环中具有极其重要的作用。然而迄今为止,对其碳通量动态的时空变异还缺乏比较分析,对碳通量的季节和年际变异的主导影响因子认识还不够清晰,不利于深入理解生态系统碳通量格局及其形成机制。该研究选取位于青藏高原东部海北站高寒灌丛草甸和高原腹地当雄站高寒草原化草甸年降水量相近的5年(2004–2008年)的涡度相关CO_2通量连续观测数据,对生态系统净初级生产力(NEP)及其组分,包括总初级生产力(GPP)和生态系统呼吸的季节、年际动态及其影响因子进行了对比分析。结果表明:灌丛草甸的CO_2通量无论是季节还是年际累积量均高于草原化草甸,并且连续5年表现为"碳汇",平均每年NEP为70 g C·m^(–2)·a^(–1),高寒草原化草甸平均每年NEP为–5 g C·m^(–2)·a^(–1),几乎处于碳平衡状态,但其源/汇动态极不稳定,在2006年–88 g C·m^(–2)·a^(–1)的"碳源"至2008年54 g C·m^(–2)·a^(–1)的"碳汇"之间转换,具有较大的变异性。这两种高寒生态系统源/汇动态的差异主要源于归一化植被指数(NDVI)的差异,因为NDVI无论在年际水平还是季节水平都是NEP最直接的影响因子;其次,灌丛草甸还具有较高的碳利用效率(CUE,CUE=NEP/GPP),而年降水量和NDVI是决定两生态系统CUE大小的关键因子。两地区除了CO_2通量大小的差异外,其环境影响因子也有所不同。采用结构方程模型进行的通径分析表明,灌丛草甸生长季节CO_2通量的主要限制因子是温度,NEP和GPP主要受气温控制,随着气温升高而增加;而草原化草甸的CO_2通量多以季节性干旱导致的水分限制为主,其次才是气温的影响,受二者的共同限制。此外,两生态系统生长季节生态系统呼吸主要受GPP和5 cm土壤温度的直接影响,其中GPP起主导作用,非生长季节生态系统展开更多
Landscapes of the mountainous regions in northwestern China comprise a unique pattern of vegetation,consisting of a mosaic of grassland and shrub-forest.Forests generally self-organize into ordered structures and coal...Landscapes of the mountainous regions in northwestern China comprise a unique pattern of vegetation,consisting of a mosaic of grassland and shrub-forest.Forests generally self-organize into ordered structures and coalesce into blocks on north-facing slopes or stripes along southeast-facing slopes,with Picea crassifolia being the most representative and dominant tree species.We investigated the tree-water status and soil-moisture dynamics at a forest site(Guantan)of the Qilian Mountains in northwest China.The 30-minute-interval measurements of tree-sap flow during the growing season of 2008 are presented,and the potential functional relations between tree transpiration and environmental factors are evaluated.Soil moisture and solar energy were identified as the most influential factors,explaining more than 70%of the variance in sap flow.Based on field measurements obtained at the forest site,a stochastic model of soil-moisture dynamics was tested;and the steady-state probability density functions(PDFs)of the long-term soil-moisture dynamics and static tree-water stress were estimated using the validated model and parameters.We found that the model reproduced measured soil moisture well,despite all the simplifying assumptions.The generated PDF of long-term soil moisture was relatively open,with middle to low average values;and the calculated density of the static tree-water stress at the forest site was largely concentrated between 0 and 0.6,suggesting a moderate water-stress situation in most cases.We argue that both water and energy are limiting factors for vegetation at the forest site.In addition,the tradeoff between reduced evapotranspiration(ET)from limited solar energy and increased soil-moisture availability may create a stressed but tolerable environment and,in turn,produce a relatively constant ecological niche favorable to Picea crassifolia growth.展开更多
基金The Second Tibetan Plateau ScientificExpeditionand Research(STEP)program(2019QZKK0106)the National Natural Science Foundation of China(91837312)Postdoctoral Science Foundation of China(2019M660751).
文摘植被降水利用效率(PUE)是量化陆地生态系统碳水耦合机制的一个关键指标,然而气候变暖如何影响青藏高原高寒草地生态系统的植被降水利用效率仍不清楚。2010年在藏北高原3个海拔(4313、4513和4693 m)上布设了增温试验平台,采用开顶式增温箱模拟气候变暖。利用农业多光谱相机获得了2014–2015年和2017–2018年植被的归一化植被指数(NDVI)和土壤调节植被指数(SAVI),并利用观测的NDVI计算了地上生物量(AGB)。利用微气候观测系统对土壤温度、土壤湿度、空气温度和相对湿度进行了观测,并计算了饱和水汽压差。结果表明:试验增温极显著(P<0.001)增加了空气温度(Ta)、土壤温度(Ts)和饱和水汽压差(VPD),而对AGB、NDVI和SAVI无显著影响(P>0.05)。试验增温显著(P<0.05)降低了海拔4313 m 4年平均的植被降水利用效率,即导致了相对干旱年份的植被降水利用效率的显著(P<0.05)减少,而对相对湿润年份的植被降水利用效率无显著影响(P>0.05)。试验增温没有显著改变海拔4513和4693 m的植被降水利用效率。总体而言,试验增温增加了3个海拔间的植被降水利用效率的差异。因此,藏北高寒草地生态系统的植被降水利用效率的温度敏感性随着海拔和观测年份的变化而变化;且气候变暖重构了藏北高原高寒草地生态系统的植被降水利用效率的海拔分布格局,即气候变暖增强了藏北不同海拔的高寒草地生态系统的植被降水利用效率的异质性。
基金supported by financial assistantships from NATP-PB,NBPGR,Pusa Campus New Delhi
文摘A study was conducted to examine the distribution pattern of four rhizomatous medicinal and aromatic plant species （MAPs） viz., Angelica glauca, Pleurospermum angelicoides, Rheum emodi and Arne- bia benthamii in different forest stands in Central Himalaya. Results show that A. glauca and P. angelicoides had a higher （50%） frequency at Chipkoan, Garpak and Phagati forest, R. emodi had a higher （60%） frequency at Rishikund, Suki and Himtoli, and A. benthamii had a higher （70%） frequency at Suki and Khambdhar The densities of A. glauca （0.6 plants·m -2 ） and P. angelicoides （0.5 plants·m -2 ） were higher at Chipkoan and Garpak sites than at other micro-sites, while densities of R. emodi （0.8 plants·m -2 ） and A. benthamii （1.0 plants·m -2 ） were higher at Suki and Khambdhar sites. A. glauca had highest total basal covers （TBC） （1.2 cm 2 ·m -2 ） at Chipkoan, P. angelicoides had highest TBC （0.92 cm 2 ·m -2） at Lati kharak site, A. benthamii had the highest TBC （6.48 cm 2 ·m -2 ） atKhambdhar, and R. emodi had highest TBC （4.53 cm 2 ·m -2 ） at Rishikund. For the four studied species, A. glauca showed a contagious distribution, P. angelicoides and R. emodi showed the random and A. benthamii showed the regular type of distribution.
文摘The geology and geomorphology of the territory as well as microclimate are local geographical features that serve as natural ecological resources. These factors influence the biosynthetic activities of plants and their phenology, promoting biodiversity and the qualitative predispositions of grapes and wine. South Tyrol is one of the smallest wine-growing regions in Italy, but owing to its position amid the Alps, it is also one of the most multifaceted, a region of wide geographical diversity and remarkable ecological range, hosting a concentration of many different vine varieties and high quality wines. This applied territorial research investigates the particular environmental circumstances that favour this case. A data set describing approximately 26,000 vineyards and 5450 hectares has been employed to evaluate 18 subzones of wines and vines selected from 86 new geographical units defined within the DOC wine region. A new environmental mapping scheme called VHTG is proposed, based on the ecological indicators of grape variety, altitude, topoclimate and the geopedology of the vineyards. Using the VHTG method analyses, the comparisons between the territories of origin and their vine varieties can be rendered simpler and more direct, and it can distinguish the most suitable ecological conditions of wine production zones. It is now possible to examine more in detail the land suitability of the different cultivars, defined by the use of the ecological indicators summarized in the VHTG method. White grape varieties such as Sylvaner and Veltliner prefer high altitudes between 600 m and 900 m, a very high solar radiation SRI index from 80 to 95, and acidic sandy soils of silicate minerals. The most complete and intense tannic structure of regional Pinot Noir correlates to quite clayey soils with dolomite mineral, slightly alkaline, on vineyards at altitudes between 350 m and 410 m, with rather low SRI index from 60 to 75. Similar geopedological conditions favour Gewürztraminer, which, however, requests SRI from 75 to
文摘高寒灌丛草甸和草甸均是青藏高原广泛分布的植被类型,在生态系统碳通量和区域碳循环中具有极其重要的作用。然而迄今为止,对其碳通量动态的时空变异还缺乏比较分析,对碳通量的季节和年际变异的主导影响因子认识还不够清晰,不利于深入理解生态系统碳通量格局及其形成机制。该研究选取位于青藏高原东部海北站高寒灌丛草甸和高原腹地当雄站高寒草原化草甸年降水量相近的5年(2004–2008年)的涡度相关CO_2通量连续观测数据,对生态系统净初级生产力(NEP)及其组分,包括总初级生产力(GPP)和生态系统呼吸的季节、年际动态及其影响因子进行了对比分析。结果表明:灌丛草甸的CO_2通量无论是季节还是年际累积量均高于草原化草甸,并且连续5年表现为"碳汇",平均每年NEP为70 g C·m^(–2)·a^(–1),高寒草原化草甸平均每年NEP为–5 g C·m^(–2)·a^(–1),几乎处于碳平衡状态,但其源/汇动态极不稳定,在2006年–88 g C·m^(–2)·a^(–1)的"碳源"至2008年54 g C·m^(–2)·a^(–1)的"碳汇"之间转换,具有较大的变异性。这两种高寒生态系统源/汇动态的差异主要源于归一化植被指数(NDVI)的差异,因为NDVI无论在年际水平还是季节水平都是NEP最直接的影响因子;其次,灌丛草甸还具有较高的碳利用效率(CUE,CUE=NEP/GPP),而年降水量和NDVI是决定两生态系统CUE大小的关键因子。两地区除了CO_2通量大小的差异外,其环境影响因子也有所不同。采用结构方程模型进行的通径分析表明,灌丛草甸生长季节CO_2通量的主要限制因子是温度,NEP和GPP主要受气温控制,随着气温升高而增加;而草原化草甸的CO_2通量多以季节性干旱导致的水分限制为主,其次才是气温的影响,受二者的共同限制。此外,两生态系统生长季节生态系统呼吸主要受GPP和5 cm土壤温度的直接影响,其中GPP起主导作用,非生长季节生态系统
基金supported by the West Light Foundation of the Chinese Academy of Sciences(awarded to Dr.Hu Liu in 2018)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(awarded to Dr.Hu Liu in 2016)
文摘Landscapes of the mountainous regions in northwestern China comprise a unique pattern of vegetation,consisting of a mosaic of grassland and shrub-forest.Forests generally self-organize into ordered structures and coalesce into blocks on north-facing slopes or stripes along southeast-facing slopes,with Picea crassifolia being the most representative and dominant tree species.We investigated the tree-water status and soil-moisture dynamics at a forest site(Guantan)of the Qilian Mountains in northwest China.The 30-minute-interval measurements of tree-sap flow during the growing season of 2008 are presented,and the potential functional relations between tree transpiration and environmental factors are evaluated.Soil moisture and solar energy were identified as the most influential factors,explaining more than 70%of the variance in sap flow.Based on field measurements obtained at the forest site,a stochastic model of soil-moisture dynamics was tested;and the steady-state probability density functions(PDFs)of the long-term soil-moisture dynamics and static tree-water stress were estimated using the validated model and parameters.We found that the model reproduced measured soil moisture well,despite all the simplifying assumptions.The generated PDF of long-term soil moisture was relatively open,with middle to low average values;and the calculated density of the static tree-water stress at the forest site was largely concentrated between 0 and 0.6,suggesting a moderate water-stress situation in most cases.We argue that both water and energy are limiting factors for vegetation at the forest site.In addition,the tradeoff between reduced evapotranspiration(ET)from limited solar energy and increased soil-moisture availability may create a stressed but tolerable environment and,in turn,produce a relatively constant ecological niche favorable to Picea crassifolia growth.
