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北美高草草原光谱特征的日变化和季节变化
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作者 G. Asrar 赵晓英 《国外畜牧学(草原与牧草)》 1990年第4期30-32,共3页
此项研究在天然高草原进行,旨在评估大草原在焚烧和未经焚烧情况下光谱特征的日变化和季节变化。我们测定了这两种情况下的光谱反射率,并用辐射传输模型进行了模拟,时间是选择的几天和在两年中任选的若干天。无论是所选的几天还是整个... 此项研究在天然高草原进行,旨在评估大草原在焚烧和未经焚烧情况下光谱特征的日变化和季节变化。我们测定了这两种情况下的光谱反射率,并用辐射传输模型进行了模拟,时间是选择的几天和在两年中任选的若干天。无论是所选的几天还是整个两年中,两种植冠在可见光和近红外光谱区的光谱特征有显著差异,这种差异在偏离垂直的太阳高度角时最大。在垂直太阳高度角时最小。未焚烧的草地上由于枯草层的存在明显影响了草冠的光谱特征。 展开更多
关键词 高草草原 光谱特征 日变化 季节
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Advances in Grassland Ecosystem Research in Northern Tibetan Plateau 被引量:25
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作者 武建双 沈振西 张宪洲 《Agricultural Science & Technology》 CAS 2009年第3期148-152,共5页
With the aggravation of global change, the response and adaptation of the unique ecosystem in Qinghai-Tibet Plateau to global change have been increasingly concerned by scientific community day by day, which makes the... With the aggravation of global change, the response and adaptation of the unique ecosystem in Qinghai-Tibet Plateau to global change have been increasingly concerned by scientific community day by day, which makes the sensitivity and fragility of this ecosystem in response to global change widely recognized by scholars. On the basis of introducing the present research process on the degenerate mechanisim, measures of and approaches to recovery, carbon cycle and primary productivity toward global change, we put forward several propositions on studying the alpine grassland ecosystem in Northern Tibetan Plateau. 展开更多
关键词 Northern Tibetan Plateau Grassland degeneration Global changes Carbon cycle Primary productivity
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Mapping the vegetation distribution of the permafrost zone on the Qinghai-Tibet Plateau 被引量:30
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作者 WANG Zhi-wei WANG Qian +12 位作者 ZHAO Lin WU Xiao-dong YUE Guang-yang ZOU De-fu NAN Zhuo-tong LIU Guang-yue PANG Qiang-qiang FANG Hong-bing WU Tong-hua SHI Jian-zong JIAO Ke-qin ZHAO Yong-hua ZHANG Le-le 《Journal of Mountain Science》 SCIE CSCD 2016年第6期1035-1046,共12页
In this paper, an updated vegetation map of the permafrost zone in the Qinghai-Tibet Plateau (QTP) was delineated. The vegetation map model was extracted from vegetation sampling with remote sensing (RS) datasets ... In this paper, an updated vegetation map of the permafrost zone in the Qinghai-Tibet Plateau (QTP) was delineated. The vegetation map model was extracted from vegetation sampling with remote sensing (RS) datasets by decision tree method. The spatial resolution of the map is 1 km×1 kin, and in it the alpine swamp meadow is firstly distinguished in the high-altitude areas. The results showed that the total vegetated area in the permafrost zone of the QTP is 1,201,751 km2. In the vegetated region, 50,260 km2 is the areas of alpine swamp meadow, 583,909 km2 for alpine meadow, 332,754 km2 for alpine steppe, and 234,828 km2 for alpine desert. This updated vegetation map in permafrost zone of QTP could provide more details about the distribution of alpine vegetation types for studying the vegetation mechanisms in the land surface processes of highaltitude areas. 展开更多
关键词 High-altitude areas Alpine vegetationtype Vegetation map Alpine swamp meadow MODIS Decision tree
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Research on the Soil Carbon Storage of Alpine Grassland under Different Land Uses in Qinghai-Tibet Plateau 被引量:2
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作者 Tao Li Lei Ji Tao Liu Zhongqi Song Shujing Yang Youmin Gan 《Journal of Agricultural Science and Technology(A)》 2013年第2期99-104,共6页
In this article, we mainly analysis the soil carbon storage of the alpine grassland under different land uses in Qinghai-Tibet Plateau. The samples of this investigation include six experimental fields which are fence... In this article, we mainly analysis the soil carbon storage of the alpine grassland under different land uses in Qinghai-Tibet Plateau. The samples of this investigation include six experimental fields which are fenced mowing grassland, artificial grassland, winter and spring grazing meadowland, summer and autumn mild grazing land, summer and autumn moderate grazing pasture and summer and autumn severe grazing land and seven soil layers included 0 cm-5 cm, 5 cm-10 cm, 10 cm-20 cm, 20 cm-30 cm, 30 cm-50 cm, 50 cm-70 cm and 70 cm-100 cm. The results show that the soil carbon storage in different soil layers will gradually reduce and the difference was remarkable (P 〈 0.05). What is more, the soil carbon storage of alpine grassland under different land uses has following sequence: winter and spring grazing grassland 〉 summer and autumn mild grazing land 〉 artificial grassland 〉 summer and autumn moderate grazing meadowland 〉 summer and autumn severe grazing pasture 〉 fenced mowing meadow, and the significant difference between them is remarkable (P 〈 0.05). 展开更多
关键词 Qinghai-Tibet Plateau alpine grassland SOIL carbon storage.
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Species-area relationship within and across functional groups at alpine grasslands on the northern Tibetan Plateau,China 被引量:1
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作者 ZHOU Nan WU Jian-shuang +2 位作者 SHEN Zhen-xi ZHANG Xian-zhou YANG Peng-wan 《Journal of Mountain Science》 SCIE CSCD 2016年第2期265-275,共11页
The species-area relationship (SAR) is one of the most fundamental concepts in community ecology and is helpful for biodiversity conservation. However, few studies have systematically addressed this topic for differ... The species-area relationship (SAR) is one of the most fundamental concepts in community ecology and is helpful for biodiversity conservation. However, few studies have systematically addressed this topic for different alpine grassland types on the Tibetan Plateau, China. We explored whether the plant composition of different functional groups affects the manner in which species richness inereases with increasing area at scales ≤ 1.0 m^2. We also compared species richness (S) within and across forbs, legumes, sedges and grasses, with sampling subplot area (A) increasing from 0.0625 m^2 to 1.0 m^2 between alpine meadow and steppe communities. We applied a logarithmic function (S = b0 + b1 ln A) to determine the slope and intercept of SAR curves within and across functional groups. The results showed that the logarithmic relationship holds true between species richness and sampling area at these small scales. Both the intercept and slope of the logarithmic forbs-area curves are significantly higher than those for the three other functional groups (P 〈 0.05). Forb accounts for about 91.9 % of the variation in the intercept and 75.0% of the variation in the slope of the SAR curve when all functional groups' data were pooled together. Our results indicated that the different SAR patterns should be linked with species dispersal capabilities, environmental filtering, and life form composition within alpine grassland communities. Further studies on the relationship between species diversity and ecosystem functions should specify the differential responses of different functional groups to variations in climate and anthropogenic disturbances. 展开更多
关键词 Changtang Nature Reserve Complementary response Plant functional groups Plant life forms Species coexistence
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Responses of Phytolith in Guinea Grass(Leymus chinensis) Leaves to Simulated Warming,Nitrogen Deposition and Elevated CO_2 Concentration in Songnen Grassland,Northeast China 被引量:3
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作者 LI Bo FENG Yingying +2 位作者 GUO Jixun JIE Dongmei SHI Lianxuan 《Chinese Geographical Science》 SCIE CSCD 2015年第4期404-413,共10页
Deposited in plant cells and their intercellular space,phytoliths,a special form of silica,could be used to determine information on plant structure and physiology especially their size and content.With the hypothesis... Deposited in plant cells and their intercellular space,phytoliths,a special form of silica,could be used to determine information on plant structure and physiology especially their size and content.With the hypothesis that phytolith in plant would change under variable climate and environment,the dominant plant species in Songnen grassland,guinea grass(Leymus chinensis),was treated by an open-top chamber(OTC) to elevate CO2 concentration,infrared heaters,and artificial nitrogen(N) addition for three years from 2006–2008.Phytoliths were extracted by wet-ashing method and analyzed by variance analysis and so on.We found that the responses to elevated CO2 are complicated,and warming is positive while N addition is negative to the deposition of phytoliths in L.chinensis leaves.Especially,warming could reduce the negative impact of N addition on phytolith in L.chinensis.The short cell's taxonomic in graminea is significant because of no disappearance with simulated environmental changes.The phytolith originated in the long cell and plant intercellular space are more sensitive to elevated CO2 concentration,warming,and N addition,and could become some new indicators for environmental changes.In conclusion,different phytolith types have various responses to simulated warming,N addition and elevated CO2 concentration. 展开更多
关键词 phytolith elevated CO2 warming N addition response
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Amino Acid and Mineral Composition of Meat from Free-range Broilers Reared on Alpine Steppe
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作者 T. Sun Z. Y. Liu R. J. Long 《Journal of Agricultural Science and Technology(A)》 2011年第8期1196-1199,共4页
An increasing number of consumers demanding health foods have favoured poultry meat from natural production system. Amino acid and mineral elements are essential nutrient, required for numerous metabolic functions, wh... An increasing number of consumers demanding health foods have favoured poultry meat from natural production system. Amino acid and mineral elements are essential nutrient, required for numerous metabolic functions, which are provided partly by the poultry. The objective of this study was to evaluate amino acid and mineral composition in meat of free-range broilers fed on grasshoppers on alpine rangeland in the Tibetan Plateau. Eighty, 28-day-old Qinjiaoma male broilers were introduced into a rangeland where there was a dense population of grasshoppers (treatment GC). Control chicken were reared under intensive condition and given a maize-soybean diet (treatment CC). At 91 days of age, 24 birds from each treatment were slaughtered. Fresh breast meats were packaged and refrigerated for determination. The results indicated that dietary grasshoppers and rearing condition significantly (P 〈 0.05) affected some amino acid and mineral elements composition. Aspartic, arginine, threonine, isoleucine and lysine were higher in the muscles from GC than those from CC, and the similar trend were also found in the content of total amino acid and essential amino acid. While tryptophan and methionine were lower (P 〈 0.05) in meat from GC than that from CC. Effect of diets and rearing condition on mineral elements was also observed, the concentration of sodium, phosphorus and iron were higher (P 〈 0.05) in muscle from GC, while calcium was higher in muscle from CC. In conclusion, the meat in free-range broilers fed on grasshoppers has the richer amino acid and mineral elements. 展开更多
关键词 Chicken grasshopper intake amino acid mineral elements grassland
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Short-term Intensive Sustainable Restoration of Grasslands and Prairies Invaded with High Densities of Nitrogen-fixing Weeds: A Test with the Invasive Plant Lespedeza Cuneata
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作者 Jack Comell Alexander Wait 《Journal of Environmental Science and Engineering(B)》 2016年第5期254-260,共7页
This study examines a management strategy for restoring grassland and prairie communities that have become degraded due to high density stands of invasive nitrogen-fixing plants. The novel management applications mini... This study examines a management strategy for restoring grassland and prairie communities that have become degraded due to high density stands of invasive nitrogen-fixing plants. The novel management applications minimize the use of herbicides and maximize the competitive interactions of native species. The management method includes two seasons of application of organic fertilizer (4-1-4), an initial herbicide (Pasture Gard, Dow Agro) application, and mowing, where mowing was a necessary treatment to control secondary growth in prairie habitats, to control high density patches of Lespedeza (L.) Cuneata, in a completely randomized factorial experiment. The herbicide was effective in reducing L. Cuneate stem density 0 stems/m^2 from an initial 88 stems/m^2 with cover reduced to 0% from 16%. The fertilizer only treatment reduced L. Cuneata percent cover to 6% from initial cover of 16%, but did not reduce the number of stems. The management strategy is an effective fast step in restoring a native prairie invaded by a nitrogen-fixing plant. 展开更多
关键词 Legumes nitrogen-fixing plants Lespedeza Cuneata prairie/grassland restoration invasive species sustainable management.
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Herbage Production and Species Richness in Sub-alpine Grasslands of Different Soil Parent Material in Northern Greece
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作者 MPOKOS J.Panagiotis YIAKOULAKI D.Maria +3 位作者 PAPAZAFEIRIOU Z.Agapi SGARDELIS Stefanos ALIFRAGIS Dimitrios PAPANIKOLAOU Konstantinos 《Journal of Mountain Science》 SCIE CSCD 2014年第6期1579-1592,共14页
Several abiotic and biotic factors were investigated as possible predictors of local species richness in two sub-alpine grasslands of Jenna and Belles Mountains in Northern Greece.For species richness modelling a hier... Several abiotic and biotic factors were investigated as possible predictors of local species richness in two sub-alpine grasslands of Jenna and Belles Mountains in Northern Greece.For species richness modelling a hierarchical modelling framework based on generalized additive models was adopted.The two sub-alpine grasslands differed in aspect,altitude and soil parent material(volcanic origin,mostly trachyte,and andesite(TA) for Jenna and metamorphic rocks,mostly gneiss(G) for Belles).12 fenced squared plots,16 m2 each,were used per grassland,where soil properties,herbage production,species presence and cover of grasses,legumes and forbs were estimated.Mean herbage production was significantly affected by slope and altitude,soil K content and floristic composition as expressed by an ordination axis.Soil p H,floristic composition and average herbage production were significant predictors of forbs and total species richness.For the former,soil N content and for the latter the occurrence of Agrostis capillaris,were also included as significant terms in the predictive model.Thepredictors for grasses species richness were N content,having a positive effect,and average herbage production.In all cases higher species richness was predicted for intermediate values of average herbage production.Differential responses were found between forbs and grasses.The predictors of their species richness were different while for the case of the common predictor(N) the responses of the two groups were also different(grasses species numbers increase and forbs species numbers decreased with increasing N).Maximum species richness of grasses was observed at relatively low production levels while forbs species richness maximized at relatively high production levels. 展开更多
关键词 Mountain pastures Biomass production Functional groups ALTITUDE Agrostis capillaris
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基因型多样性、干旱、菌根对优势C_(4)植物生产力及功能性状的影响
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作者 Smriti Pehim Limbu Meghan L.Avolio 《Journal of Plant Ecology》 SCIE CSCD 2023年第1期188-202,共15页
虽然许多物种的遗传多样性和植物生产力之间的关系已经得到证实,但环境条件和生物群落是否会改变这种关系尚不清楚。针对这一问题,本文研究了基因型多样性、干旱和菌根对植物生产力和植物性状的交互作用。该研究建立在堪萨斯州曼哈顿南... 虽然许多物种的遗传多样性和植物生产力之间的关系已经得到证实,但环境条件和生物群落是否会改变这种关系尚不清楚。针对这一问题,本文研究了基因型多样性、干旱和菌根对植物生产力和植物性状的交互作用。该研究建立在堪萨斯州曼哈顿南部的康扎草原生物研究站。本研究对焦点物种大须芒草(Andropogon gerardii)采用两种水平的基因型丰富度处理:单种栽培和3基因型混合栽培。在试验区的一半以上建立避雨棚进行抗旱处理,并在每个基因型丰富度和抗旱处理的选定盆栽中使用硫菌酯-甲基杀菌剂抑制丛枝菌根真菌的生长。结果表明,基因型丰富度和菌根对大须芒草的地上生物量无显著影响。干旱对大须芒草各基因型地上生物量、成花数和过早结实有不同的影响,而且生物量和功能性状在单独栽培和混合栽培处理中有显著差异。这些研究结果说明,干旱和基因型丰富度对不同基因型的植物有不同的结果。 展开更多
关键词 高草草原 大须芒草(Andropogon gerardii) C_(4)植物 遗传多样性 互利共生
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美国密苏里大学植物园
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作者 金文驰 《人与自然》 2019年第9期80-87,共8页
美国不少知名高校都设有植物园,其中一些园子在国际上享有盛誉,比如哈佛大学的阿诺德树木园、收集并展示了12000多种(含亚种)植物的加州大学伯克利分校植物园……这些高校往往把植物园设在教学区之外,不过创立于1839年的美国密苏里大学... 美国不少知名高校都设有植物园,其中一些园子在国际上享有盛誉,比如哈佛大学的阿诺德树木园、收集并展示了12000多种(含亚种)植物的加州大学伯克利分校植物园……这些高校往往把植物园设在教学区之外,不过创立于1839年的美国密苏里大学却是个例外。这座大学的整个校园都被官方设为植物园,因此无论用'花园学校'还是'学校花园'来概括都是恰当的。 展开更多
关键词 植物园 展览温室 高草草原 密苏里大学
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探访私立保护区:美国肖氏自然保护区
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作者 金文驰(文/图) 《生命世界》 2021年第11期82-91,共10页
在美国中部城市圣路易斯西郊约60千米处,坐落着一座私立保护区:肖氏自然保护区(Shaw Nature Reserve)。草浪翻滚的高草草原、缀满繁花的林间空地、高大的河滩地森林、鸟啼蛙鸣的湿地……都汇聚到这片9.7平方千米的土地上。保护区中还有... 在美国中部城市圣路易斯西郊约60千米处,坐落着一座私立保护区:肖氏自然保护区(Shaw Nature Reserve)。草浪翻滚的高草草原、缀满繁花的林间空地、高大的河滩地森林、鸟啼蛙鸣的湿地……都汇聚到这片9.7平方千米的土地上。保护区中还有一个密苏里州的自然区,保存着被人类改造前的原初自然景观。 展开更多
关键词 高草草原 密苏里州 保护区 河滩地 林间空地 圣路易斯 肖氏 自然景观
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Effects of Enclosure on Plant and Soil Nutrients in Different Types of Alpine Grassland 被引量:7
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作者 WANG Fang HE Yongtao +6 位作者 FU Gang NIU Ben ZHANG Haorui LI Meng WANG Zhipeng WANG Xiangtao ZHANG Xianzhou 《Journal of Resources and Ecology》 CSCD 2020年第3期290-297,共8页
Enclosure is one of the most widely used management tools for degraded alpine grassland on the northern Tibetan Plateau, but the responses of different types of grassland to enclosure may vary, and research on these r... Enclosure is one of the most widely used management tools for degraded alpine grassland on the northern Tibetan Plateau, but the responses of different types of grassland to enclosure may vary, and research on these responses can provide a scientific basis for improving ecological conservation. This study took one site for each of three grassland types(alpine meadow, alpine steppe and alpine desert) on the northern Tibetan Plateau as examples, and explored the effects of enclosure on plant and soil nutrients by comparing differences in plant community biomass, leaf-soil nutrient content and their stoichiometry between samples from inside and outside the fence. The results showed that enclosure can significantly increase all aboveground biomass in these three grassland types, but it only increased the 10–20 cm underground biomass in the alpine desert. Enclosure also significantly increased the leaf nutrient content of the dominant plants and contents of total nitrogen(N), total potassium(K), and organic carbon(C) in 10–20 cm soil in alpine desert, thus changing the stoichiometry between C, N and P(phosphorus). However, enclosure significantly increased only the N content of dominant plant leaves in alpine steppe, while other nutrients and stoichiometries of both plant leaves and soil did not show significant differences in alpine meadow and alpine steppe. These results suggested that enclosure has differential effects on these three types of alpine grasslands on the northern Tibetan Plateau, and the alpine desert showed the most active ecological conservation in the responses of its soil and plant nutrients. 展开更多
关键词 ENCLOSURE alpine meadow alpine steppe alpine desert steppe plant nutrient soil nutrient
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Distribution of fatty acids in the alpine grassland soils of the Qinghai-Tibetan Plateau 被引量:2
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作者 DAI Guo Hua ZHU Shan Shan +3 位作者 LIU Zong Guang CHEN Li Tong HE Jin Sheng FENG Xiao Juan 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第7期1329-1338,共10页
As an important biomarker, fatty acids(FAs) have been extensively used to trace the origin of organic matter in sediments and soils. However, studies of the distribution and abundance of FAs in alpine grassland soils ... As an important biomarker, fatty acids(FAs) have been extensively used to trace the origin of organic matter in sediments and soils. However, studies of the distribution and abundance of FAs in alpine grassland soils are still rare, especially on the Qinghai-Tibetan Plateau(QTP), the highest plateau in the world, which contributes sediments to many large rivers in Asia. This study investigates the composition, distribution and source of FAs with increasing soil depths from 17 typical alpine grassland sites in the QTP. The most abundant FAs included the ubiquitous C16 FA and even-numbered long-chain FAs(C20–C30), indicating mixed inputs from microbial and higher plant sources. Source apportionment showed that higher plants were the dominant contributor of FAs(approximately 40%) in QTP soils. The abundance of FAs decreased with soil depth, with the highest value(1.08±0.09 mg/g C) at a 0–10 cm depth and the lowest value(0.46±0.12 mg/g C) at a 50–70 cm depth, due to much lower plant inputs into the deeper horizons. The total concentration of FAs was negatively correlated to the mean annual temperature(MAT; P<0.05) and soil p H(P<0.01), suggesting that the preservation of FAs was favored in low-MAT and low-p H soils on the QTP. The abundance of fresh C source FAs increased significantly with the mean annual precipitation(MAP; P<0.05), indicating that high MAP facilitates the accumulation of fresh FAs in QTP soils. Other environmental parameters, such as the soil mineral content(aluminum and iron oxide), microbial community composition as well as litter quality and quantity, may also exert a strong control on the preservation of FAs in QTP soils and warrant further research to better understand the mechanisms responsible for the preservation of FAs in QTP soils. 展开更多
关键词 Qinghai-Tibetan Plateau Soil organic matter Biomarker Fatty acids Distribution sources
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