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基于核心素养的地理教学实践——以《植被》为例
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作者 余宝 《中华活页文选(高中版)》 2020年第4期0024-0026,共3页
本文尝试以一节《植被》教学内容为例实施地理实践力教学,学生利用小组合作学习的方式开展校园研学活动。学生分组观察和记录校园植被的生长情况,了解校园树木与环境的关系,学生由传统课堂注重知识的学习转向实践探究学习,逐渐养成具有... 本文尝试以一节《植被》教学内容为例实施地理实践力教学,学生利用小组合作学习的方式开展校园研学活动。学生分组观察和记录校园植被的生长情况,了解校园树木与环境的关系,学生由传统课堂注重知识的学习转向实践探究学习,逐渐养成具有解决真实情境下问题的能力。教师利用课堂实践教学活动达成对学生地理核心素养的培养,反思地理教学实践,落实立德树人的根本任务。 展开更多
关键词 地理实践力 地理教学 《植被》 情境
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Satellite remote sensing reveals overwhelming recovery of forest from disturbances in Asia
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作者 Yiying Zhu Hesong Wang Anzhi Zhang 《Atmospheric and Oceanic Science Letters》 2025年第1期46-51,共6页
Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability ... Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability of forests.At the same time,detailed accounts of disturbances and forest responses are not yet well quantified in Asia.This study employed the Breaks For Additive Seasonal and Trend method-an abrupt-change detection method-to analyze the Enhanced Vegetation Index time series in East Asia,South Asia,and Southeast Asia.This approach allowed us to detect forest disturbance and quantify the resilience after disturbance.Results showed that 20%of forests experienced disturbance with an increasing trend from 2000 to 2022,and Southeast Asian countries were more severely affected by disturbances.Specifically,95%of forests had robust resilience and could recover from disturbance within a few decades.The resilience of forests suffering from greater magnitude of disturbance tended to be stronger than forests with lower disturbance magnitude.In summary,this study investigated the resilience of forests across the low and middle latitudes of Asia over the past two decades.The authors found that most forests exhibited good resilience after disturbance and about two-thirds had recovered to a better state in 2022.The findings of this study underscore the complex relationship between disturbance and resilience,contributing to comprehension of forest resilience through satellite remote sensing. 展开更多
关键词 Forest ecosystem Enhanced vegetation index Breaks for additive seasonal and trend method DISTURBANCE RESILIENCE
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山西省植被指数时空变化特征及其对气候变化的响应 被引量:6
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作者 李丽红 贾琇明 刘珺 《湖北农业科学》 2015年第17期4143-4147,共5页
基于2001-2013年山西省中分辨率成像光谱仪(MODIS)植被指数产品(MOD 13Q1)和气象数据(气温、降水量),利用斜率分析法、相关系数分析法等方法 ,研究近13年来植被指数(增强型植被指数EVI、归一化植被指数NDVI)的时空变化特征,以及植被覆... 基于2001-2013年山西省中分辨率成像光谱仪(MODIS)植被指数产品(MOD 13Q1)和气象数据(气温、降水量),利用斜率分析法、相关系数分析法等方法 ,研究近13年来植被指数(增强型植被指数EVI、归一化植被指数NDVI)的时空变化特征,以及植被覆盖变化对气候变化的响应。结果表明,年际变化方面,整体EVI和NDVI年均值显著增加,每个月均值也呈递增趋势,其中7月份的年际增长变化最为显著(EVI、NDVI的线性增长率分别为0.003 8和0.005 7);空间分布上,植被覆盖较茂密的地区主要分布在山区一带,植被稀疏区主要位于盆地附近;植被指数与年均降水量呈显著正相关,与年均气温整体上呈负相关,显著性并不明显,表明植被覆盖受降水变化影响较大,对其变化响应较强,受温度变化影响较小,呈弱响应关系。 展开更多
关键词 山西省 气温 降水量
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《植被科学手册》——一套在林学上具有很大价值的世界学术名著
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作者 胡涌 《北京林业大学学报》 CAS 1987年第2期200-200,共1页
众所周知,长期以来在植被生态学的理论研究上存在着众多的学派,它们各自的特色都非常明显,以致一直没有产生一部完整论述世界植被理论的权威性专著。1964年在爱丁堡(Edinburgh)国际植物学会上,荷兰的I.M.Weisbach—Junk夫人提出了由她... 众所周知,长期以来在植被生态学的理论研究上存在着众多的学派,它们各自的特色都非常明显,以致一直没有产生一部完整论述世界植被理论的权威性专著。1964年在爱丁堡(Edinburgh)国际植物学会上,荷兰的I.M.Weisbach—Junk夫人提出了由她的出版公司(Dr.W.Junk b.v.)出版一套国际性的《植被科学手册》的计划。其目的是对该学科从历史到各学派的理论及方法做全面论述。 展开更多
关键词 《植被科学手册》 林学 植被生态学 书评
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Physicochemical composition and climate response of surface sediments at different altitudes in Motuo on the southern slope of the Himalayas
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作者 XIE Mengping SONG Yougui +2 位作者 LAN Minwen ZHANG Mingyu HAN Yixiao 《地球环境学报》 CSCD 2024年第4期624-640,共17页
Background,aim,and scope Certain physicochemical indexes of topsoil are closely related to climatic factors including temperature,and precipitation.Understanding the relationship between modern topsoil properties and ... Background,aim,and scope Certain physicochemical indexes of topsoil are closely related to climatic factors including temperature,and precipitation.Understanding the relationship between modern topsoil properties and climatic factors is essential for quantitative paleoclimate reconstruction.Motuo located in the eastern Himalayas,exhibits a significant elevation gradient of over 7000 m from Nnamjagbarwa Peak(7782 m a.s.l.)to the Baxika(150 m a.s.l.).This region features a complete vertical zonation of vegetation,from alpine meadow to tropical forest,presenting an ideal place to investigate the relationships among vegetation,soil and climate conditions across altitudinal gradients.This study aims to explore the vertical variations in the physicochemical composition of topsoil and its relationship with temperature and precipitation.Materials and methods Twenty-seven topsoil samples were collected at 100 m intervals from 800 m to 3600 m a.s.l.along the southern slope of the Himalayas.Grain size,magnetic susceptibility and geochemical elements were measured to discuss the vertical variation characteristics of topsoil composition and their correlation with climatic factors.Results(1)The grain size of topsoil at different altitudes in Motuo is mainly composed of sand accounting for an averaged 53.2%,followed by silt and clay.(2)In the mixed forest zone,frequency dependent magnetic susceptibility(χfd%)shows a clear relationship with altitude,and clay is positively correlated with both altitude and climatic factors.(3)The oxides of topsoil in this area mainly consist of SiO_(2),Al_(2)O_(3) and Fe_(2)O_(3),followed by MgO,CaO,Na_(2)O and K_(2)O,with slight variations in the primary components at different altitudes.The sensitivity of elements to climate varies across different altitudes and vegetation zone,likely due to the region’s complex topography and vegetation.(4)Physical and biological weathering dominates in the broad-leaved forest zone of Motuo,while chemical weathering is more prominent in the coniferous forest zone,with the mixed forest zone falling in between.Discussion The formation of topsoil across the three vegetation zones is influenced by various factors,including parent material,vegetation,and climate.In the broad-leaved forest zone,physical weathering(precipitation,root wedging etc.)and pedogenesis dominate,resulting in finer grain size.The χ_(fd)% increases with altitude likely due to the high temperature and abundant precipitation in this zone,which facilitate the transformation of strong magnetic miners into weaker ones,particularly when the soil is oversaturated.Zirconium(Zr),primarily found in zircon,is depleted at lower altitudes by strong current erosion.Barium(Ba)is similarly reduced at low altitudes in this zone.In mixed forest zone,clay content is the lowest,indicating weaker physical weathering conditions than broad-leaved forest zone.The coarser grain size may result from the combined effects of topography and vegetation coverage.Magnetic susceptibility and organic matter show a positive correlation with altitude.Zr concentration is higher than that in the broad-leaved forest zone,likely resulting from decreased precipitation.In the coniferous zone,the clay content shows considerable fluctuations,with grain size generally becoming finer as altitude increases.This trend may be explained by intensified soil disintegration from seasonal freeze-thaw cycles.The χ_(fd)% values lack a clear trend or pattern,possibly due to soil erosion causing the migration of magnetic minerals or insufficient iron precipitation,which reduces the concentration of magnetic minerals in the soil.Additionally,a positive correlation is observed between altitude and organic matter content,with higher altitudes associated with greater organic matter accumulation.This may be attributed to lower microbial activity in colder conditions,which slows the decomposition and transformation of organic matter.Conclusions The variations in grain size,magnetic susceptibility,and geochemical elements differ across altitudes and vegetation zones,closely connected to the complex interplay of terrain,vegetation,and climate in Motuo.In the mixed forest,altitude has a significant impact onχfd%,and the clay component is particularly sensitive to changes in altitude,mean annual temperature,and precipitation.Zr shows a strong correlation with altitude and climate factors,making it a valuable indicator for assessing changes in atmospheric precipitation within specific altitude ranges.Recommendations and perspectives This study enhances our understanding of the relationships between the physicochemical properties of topsoil and climate conditions,offering valuable insights for paleoclimate reconstruction in Motuo. 展开更多
关键词 southern slope of the Himalayas MOTUO TOPSOIL altitude difference vegetation zone physicochemical indexes
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Vegetation-Climate Relationship and Its Application in the Division of Vegetation Zone in China 被引量:39
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作者 方精云 宋永昌 +1 位作者 刘鸿雁 朴世龙 《Acta Botanica Sinica》 CSCD 2002年第9期1105-1122,共18页
Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundat... Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundation for understanding the vegetation distribution and theoretically serving vegetation regionalization. Vegetation regionalization is a theoretical integration of vegetation studies and provides a base for physiogeographical regionalization as well as agriculture and forestry regionalization. Based on a brief historical overview on studies of vegetation_climate relationships and vegetation regionalization conducted in China, we review the principles, bases and major schemes of previous vegetation regionalization and discuss on several contentious boundaries of vegetation zones in the present paper. We proposed that, under the circumstances that the primary vegetation has been destroyed in most parts of China, the division of vegetation zones/regions should be based on the distribution of primary and its secondary vegetation types and climatic indices that delimit distribution of the vegetation types. This not only reveals the closed relationship between vegetation and climate, but also is feasible practically. Although there still are divergence of views on the name and their boundaries of the several vegetation zones, it is commonly accepted that there are eight major vegetation regions in China, i.e. cold temperate needleleaf forest region, temperate needleleaf and broadleaf mixed forest region, warm temperate deciduous broadleaf forest region, subtropical evergreen broadleaf forest region, tropical monsoon forest and rain forest region, temperate steppe region, temperate desert region, and Qinghai_Xizang (Tibetan) Plateau high_cold vegetation region. Analyzing characteristics of vegetation and climate of major vegetation boundaries, we suggested that: 1) Qinling Mountain_Huaihe River line is an important arid/humid climatic, but not a thermal climatic boundary, and thus can not also be regarded as the northern limit of the subtropical vegetation zone; 2) the northern limit of subtropical vegetation zone in China is along the northern coast of the Yangtze River, from Hangzhou Bay, via Taihu Lake, Xuancheng and Tongling in Anhui Province, through by southern slope of the Dabie Mountains, to Wuhan and its west, coinciding with a warmth index ( WI ) value of 130-140 ℃·month; 3) the tropical region is limited in a very small area in southeastern Hainan Island and southern edge of Taiwan Island; and 4) considering a significant difference in climates between the southern and northern parts of the warm temperate zone, we suggested that the warm temperate zone in China is divided into two vegetation regions, deciduous broadleaf woodland region and deciduous and evergreen broadleaf mixed forest region, the Qinling Mountain_Huaihe River line being as their boundary. We also claimed that the zonal vegetation in North China is deciduous broadleaf woodland. Finally, we emphasized the importance of dynamic vegetation regionalization linked to climate changes. 展开更多
关键词 China dynamic vegetation regionalization arid/humid climate northern limit of subtropical zone Qinling Mountain_Huaihe River line thermal climate vegetation_climate relationship vegetation regionalization vegetation zone
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Study on Soil Microbiotic Crust and Its Influences on Sand-fixing Vegetation in Arid Desert Region 被引量:132
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作者 李新荣 张景光 +2 位作者 王新平 刘立超 肖洪浪 《Acta Botanica Sinica》 CSCD 2000年第9期965-970,共6页
Based on secular fixed_site data in the artificial sand_fixing vegetation district at the southeast fringe of the Tengger Desert, the formative characteristics of soil microbiotic crusts and its influences on vegetati... Based on secular fixed_site data in the artificial sand_fixing vegetation district at the southeast fringe of the Tengger Desert, the formative characteristics of soil microbiotic crusts and its influences on vegetation dynamics were analyzed. Once sand barrier and artificial vegetation have stabilized the surface of the sifting sand, could form aeolian deposition crust and then evolve into algae_dominated crust. Such processes result from the interactions of physical effects of atmospheric dust and silt deposition on sand surface, sinking and raindrop impact, and soil microorganism activities. Under the condition of less than 200 mm precipitation, the presence of microbiotic crust changes the soil hydraulic conductivity, alters the temporal and spatial distribution of the limited precipitation in sand layer and leads to the decline of deep_rooted shrubs. The development of microbiotic crust and subsurface soil affects the plant growth and seed rain distribution, as a result, the diversity of plant species gradually tend to become saturated and finally affects the vegetation stability. 展开更多
关键词 arid desert region microbiotic crust sand_fixing vegetation
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Effect of Different Vegetation Types on Soil Erosion by Water 被引量:26
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作者 张岩 刘宝元 +1 位作者 张清春 谢云 《Acta Botanica Sinica》 CSCD 2003年第10期1204-1209,共6页
The C factor in Universal Soil loss Equation reflecting the effect of vegetation on soil erosion by water is one of the important parameters for estimating soil erosion rate and selecting appropriate land use patterns... The C factor in Universal Soil loss Equation reflecting the effect of vegetation on soil erosion by water is one of the important parameters for estimating soil erosion rate and selecting appropriate land use patterns. In this study, the C factor for nine types of grassland and woodland was estimated from 195 plot-year observation data of six groups of soil erosion experiments on Loess Plateau. The result indicates that the effects of woodland and grassland on soil erosion keep approximately uniform after two or three years' growth. The estimated woodland C factor ranges from 0.004 to 0.164, and the grassland C factor ranges from 0.071 to 0.377, showing that the effect of woodland and grassland on soil conservation is greatly better than that of cropland. The study results can be used to compare or estimate the soil loss from land with different vegetation cover, and are the useful references for land use pattern selection and the project of returning cropland to forest or grassland. 展开更多
关键词 soil erosion by water C factor WOODLAND GRASSLAND CROPLAND
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Seasonal Dynamics of Terrestrial Net Primary Production in Response to Climate Changes in China 被引量:32
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作者 朴世龙 方精云 陈安平 《Acta Botanica Sinica》 CSCD 2003年第3期269-275,共7页
Study on seasonal responses of terrestrial net primary production (NPP) to climate changes is to help understand feedback between climate systems and terrestrial ecosystems and mechanisms of increased NPP in the north... Study on seasonal responses of terrestrial net primary production (NPP) to climate changes is to help understand feedback between climate systems and terrestrial ecosystems and mechanisms of increased NPP in the northern middle and high latitudes. In this study, time series dataset of normalized difference vegetation index (NDVI) and corresponding ground-based information on vegetation, climate, soil, and solar radiation, together with an ecological process model, were used to explore the seasonal trends of terrestrial NPP and their geographical differences in China from 1982 to 1999. As the results,. seasonal total NPP in China showed a significant increase for all four seasons (spring, summer, autumn and winter) during the past 18 years. The spring NPP indicated the largest increase rate, while the summer NPP was with the largest increase in magnitude. The response of NPP to climate changes varied with different vegetation types. The increased NPP was primarily led by an advanced growing season for broadleaf evergreen forest, needle-leaf evergreen forest, and needle-leaf deciduous forest, whilst that was mainly due to enhanced vegetation activity (amplitude of growth cycle) during growing season for broadleaf deciduous forest, broadleaf and needle-leaf mixed forest, broadleaf trees with groundcover, perennial grasslands, broadleaf shrubs with grasslands, tundra, desert, and cultivation. The regions with the largest increase in spring NPP appeared mainly in eastern China, while the areas with the largest increase in summer NPP occurred in most parts of Northwestern China, Qinghai-Xizang Plateau, Mts. Xiaoxinganling-Changbaishan, Sanjiang Plain, Songliao Plain, Sichuan Basin, Leizhou Peninsula, part of the middle and lower Yangtze River, and southeastern mountainous areas of China. In autumn, the largest NPP increase appeared in Yunnan Plateau-Eastern Xizang and the areas around Hulun Lake. Such different ways of the NPP responses depended on regional climate attributes and their changes. 展开更多
关键词 Carnegie-Ames-Stanford-Approach (CASA) model net primary production (NPP) seasonal change normalized difference vegetation index (NDVI) climate change
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Distribution patterns of vegetation biomass and nutrients bio-cycle in alpine tundra ecosystem on Changbai Mountains,Northeast China 被引量:4
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作者 魏晶 姜萍 +2 位作者 于德永 吴钢 付海威 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期271-278,共8页
A study was conducted to test the correlation between biomass and elevation and the differences in concentration and storks of nutrients among five vegetation types (Felsenmeer alpine tundra vegetation-FA, Lithic alp... A study was conducted to test the correlation between biomass and elevation and the differences in concentration and storks of nutrients among five vegetation types (Felsenmeer alpine tundra vegetation-FA, Lithic alpine tundra vegetation-LA, Typical alpine tundra vegetation-TA, Meadow alpine tundra vegetation-MA, and Swamp alpine tundra vegetation-SA) on alpine tundra of Changbai Mountains, Jilin Province, China in growing seasons of 2003, 2004 and 2005. The biomass of 43 mono-species and soil nutrients in alpine tundra ecosystem were also investigated. Dominant species from Ericaceae (such as Rhododendron chrysanthum and Vaccinium jliginosum var. alpinum) were taken to analyze organ biomass distribution. Result showed that the biomass and elevation had a significant correlation (Biomass-237.3 in(Elevation) +494.36; R^2=0.8092; P〈0.05). No significant differences were found in phosphorus and sulphur concentrations of roots, stems and leaves among the five vegetation types. There were significant differences in nitrogen and phosphorus stocks of roots, stems and leaves and in sulphur stock of stems and leaves among TA, MA, and SA vegetation types (p〈0.05). The nutrient stock of five vegetations was averagely 72.46 kg.hm^-2, of which N, P, S were 48.55, 10.33 and 13.61 kg·hm^-2, respectively. Soil N and S concentrations in meadow alpine tundra soil type was significantly higher than those in other four soil types (Cold desert alpine tundra soil, Lithic alpine tundra soil, Peat alpine tundra soil, and Gray alpine tundra soil). Phosphorous concentration in SA type was higher (p〈0.05) than in other types. Soil nutrient stock (0-20cm) was averagely 39.59 t.hm^-2, of which N, P, S were 23.74, 5.86, 9.99 t·hm^-2, respectively. 展开更多
关键词 Nutrients bio-cycle STOCK Vegetation type Soil type Vegetation biomass
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Intra-annual Vegetation Change Characteristics in the NDVI-Ts Space:Application to Farming-Pastoral Zone in North China 被引量:6
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作者 陈云浩 李晓兵 +2 位作者 史培军 窦闻 李霞 《Acta Botanica Sinica》 CSCD 2003年第10期1139-1145,共7页
Land use/land cover change (LUCC) mapping and analysis using multi-temporal normalize difference vegetation index (NDVI) data have been well documented. Recent empirical studies have documented that many new methods w... Land use/land cover change (LUCC) mapping and analysis using multi-temporal normalize difference vegetation index (NDVI) data have been well documented. Recent empirical studies have documented that many new methods with high accuracy of retrieved land surface temperature ( Ts) have been developed. Thus, the combination of land surface temperature and NDVI has the greatest potential to improve the surface vegetation dynamic monitoring. In this study, the following objectives are pursued to: (1) introduce the practical method to produce the Ts, NDVI and Ts/NDVI based on remotely sensed data; (2) investigate the different retrieved result of vegetation cover information from NDVI, Ts and Ts/NDVI data sets, and analyze the intra-annual time trajectories of different vegetation cover categories in the NDVI- Ts space for farming-pastoral zone in North China, and (3) quantitative analysis the difference in using NDVI, Ts and Ts/NDVI data sets to express information based on the indices (information entropy and averaged information grads), and evaluate the relative role of Ts/NDVI data set in the discrimination of different vegetation cover categories through comparison to traditional NDVI data set. 展开更多
关键词 vegetation index land surface temperature NDVI-Ts space information entropy
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Water Relations on Alhagi sparsifolia in the Southern Fringe of Taklamakan Desert 被引量:23
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作者 李向义 张希明 +5 位作者 曾凡江 Andrea FOETZKI Frank M .THOMAS 李小明 Michael RUNGE 何兴元 《Acta Botanica Sinica》 CSCD 2002年第10期1219-1224,共6页
Water relations of Alhagi sparsifolia Shap. at the transition zone between oases and sandy desert were studied in the southern fringe of Taklamakan Desert. Results showed that A. sparsifolia maintained the positive tu... Water relations of Alhagi sparsifolia Shap. at the transition zone between oases and sandy desert were studied in the southern fringe of Taklamakan Desert. Results showed that A. sparsifolia maintained the positive turgor during the summer. The steady high predawn water potential (psi(P)) indicated A. sparsifolia had sufficient hydration and water supply in growing season. In July, water deficit caused by drought stress had no effect on the transpiration of A. sparsifolia. Therefore, drought stress is not a main factor affecting the survival of plants. The physiological adaptation to drought of A. sparsifolia was shown mainly at the leaf level by significant difference (DeltaII) and relative water content (RWC) between the osmotic pressure at full turgor and at turgor loss, by occurring of osmotic adjustment, by high percentage of dry mass-related water content ( WCsat), by RWC at turgor loss point ( RWCp) in stable level and low RWC of the saturated symplast (RWCsym). However, the morphological features of transpiring surface reduction and deep root system seem to be the main way for the plant to adapt to the extreme drought environment. Result also suggests that one time of irregular irrigation in summer will not be helpful to recover water status of A. sparsifolia in location where the water table is very low. 展开更多
关键词 Alhagi sparsifolia water relation drought stress water potential PV parameters irrigation effect
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Detecting Vegetation Fractional Coverage of Typical Steppe in Northern China Based on Multi-scale Remotely Sensed Data 被引量:15
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作者 李晓兵 陈云浩 +1 位作者 史培军 陈晋 《Acta Botanica Sinica》 CSCD 2003年第10期1146-1156,共11页
One of the study objectives of global change is land use/cover change (LUCC) by using multiscale remotely sensed data on global and regional scale. In this paper, field sample, digital camera, Landsat-ETM+ (ETM+, Enha... One of the study objectives of global change is land use/cover change (LUCC) by using multiscale remotely sensed data on global and regional scale. In this paper, field sample, digital camera, Landsat-ETM+ (ETM+, Enhanced Thematic Mapper) image and the National Oceanic and Atmospheric Administration/the advanced very high resolution radiometer (NOAA/AVHRR) image were integrated to detect, simulate and analyze the vegetation fractional coverage of typical steppe in northern China. The results show: (1) Vegetation fractional coverage measured by digital camera is more precise than results measured by other methods. It can be used to validate other measuring results. (2) Vegetation fractional coverage measured by 1 m 2 field sample change fluctuantly for different observers and for different sample areas. In this experiment, the coverage is generally high compared with the result measured by digital camera, and the average absolute error is 9.92%, but two groups measure results, correlation coefficient r(2) = 0.89. (3) Three kinds of methods using remotely sensed data were adopted to simulate the vegetation fractional coverage. Average absolute errors of the vegetation fractional coverage, measured by ETM+ and NOAA, are respectively 7.03% and 7.83% compared with the result measured by digital camera. When NOAA pixel was decomposed by ETM+ pixels after geometrical registry, the average absolute errors measured by this method is 5.68% compared with the digital camera result. Correction coefficients of three results with digital camera result r(2) are respectively 0.78, 0.61 and 0.76. (4) The result of statistic model established by NOAA-NDVI (NDVI, Normalized Difference Vegetation Index) and the vegetation fractional coverage measured by digital camera show lower precision (r(2) = 0.65) than the result of statistic model established by ETM+-NDVI and digital camera coverage then converted to NOAA image (r(2) = 0.80). Pixel decomposability method improves the precision of measuring the vegetation fractional coverage on a large scale. This is a significant practice on scaling by using remotely sensed data. Integrated application of multi-scale remotely sensed data in earth observation will be an important approach to promoting measuring precision of ecological parameters. 展开更多
关键词 multi-scale remote sensing typical steppe vegetation fractional coverage
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Estimation of Net Primary Productivity of Terrestrial Vegetation in China by Remote Sensing 被引量:31
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作者 陈利军 刘高焕 冯险峰 《Acta Botanica Sinica》 CSCD 2001年第11期1191-1198,共8页
Among the many approaches for studying the net primary productivity (NPP), a new method by using remote sensing was introduced in this paper. With spectral information source (the visible band, near infrared band and ... Among the many approaches for studying the net primary productivity (NPP), a new method by using remote sensing was introduced in this paper. With spectral information source (the visible band, near infrared band and thermal infrared band) of NOAA-AVHRR, we can get the relative index and parameters, which can be used for estimating NPP of terrestrial vegetation. By means of remote sensing, the estimation of biomass and NPP is mainly based on the models of light energy utilization. In other words, the biomass and NPP can be calculated from the relation among NPP, absorbed photosynthetical active radiation (APAR) and the rate (epsilon) of transformation of APAR to organic matter, thus: NPP = ( FPAR x PAR) x [epsilon * x sigma (T) x sigma (E) x sigma (S) x (1 - Y-m) x (1 - Y-g)]. Based upon remote sensing ( RS) and geographic information system (GIS), the NPP of terrestrial vegetation in China in every ten days was calculated, and the annual NPP was integrated. The result showed that the total NPP of terrestrial vegetation in China was 6.13 x 10(9) t C . a(-1) in 1990 and the maximum NPP was 1 812.9 g C/m(2). According to this result, the spatio-temporal distribution of NPP was analyzed. Comparing to the statistical models, the RS model, using area object other than point one, can better reflect the distribution of NPP, and match the geographic distribution of vegetation in China. 展开更多
关键词 remote sensing net primary productivity absorbed photosynthetical active radiation light energy utilization BIOMASS
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Influence of Vegetation Coverage on Surface Runoff and Soil Moisture in Rainy Season in Dry-hot Valley 被引量:7
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作者 郭芬芬 南岭 +1 位作者 陈安强 刘刚才 《Agricultural Science & Technology》 CAS 2010年第4期138-143,共6页
[Objective]The research aimed to study the effects of vegetation coverage on the changes of soil moisture in rainy season in dry-hot valley.[Method]The surface runoff and soil moisture of slope with vegetation coverag... [Objective]The research aimed to study the effects of vegetation coverage on the changes of soil moisture in rainy season in dry-hot valley.[Method]The surface runoff and soil moisture of slope with vegetation coverage and bare land in rainy reason in Jinsha River at Yuanmou County of Yunnan Province were observed continuously.Moreover,the statistical analysis was made based on the observation data.[Result]The vegetation coverage could decrease surface runoff and the surface runoff on bare land(CK) was 22 times as the plot with vegetation coverage.The soil water content in 0-180 cm layer with vegetation coverage increased by 37.8% than bare land.The stability of soil moisture content in deep layer was enhanced and the physical properties stability of soil was maintained.The soil moisture content in different depth of soil had significant difference and the changes of soil moisture content were obviously different.[Conclusion]The vegetation coverage of slope could change the soil hydrology obviously and keep soil moisture at the higher level,especially at soil layer below 20 cm. 展开更多
关键词 Vegetation coverage Surface runoff Soil moisture Dry-hot valley
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Status of urban vegetation in Guangzhou City 被引量:12
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作者 管东生 陈玉娟 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期249-252,共4页
According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey f... According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey for soil, species di-versity, roadside trees and ecological function of urban vegetation in Guangzhou City. The results showed that: (1) soil densi-ties of urban roadside and park forests were higher than mean density of natural forest soil. The pH values of soil in urban roadside were higher too, and the content of organic matter and the concentration of nitrogen were lower. (2) Species diversity of urban vegetation was lower. The most number of species was only 16 species in tree layers of urban forest. (3) Tree growth was limited by narrow space in high-density urban area, where the trees with defects and disorders were common. (4) Com-paring with mature natural forests, the productivity of urban vegetation was lower. The effect of urban vegetation on balance of carbon and oxygen were influenced by the low primary production of urban vegetation. Therefore, the growth condition for urban vegetation should be improved. Biodiversity, primary production and ecological function should be increased for urban vegetation in order to improve urban eco-environment. 展开更多
关键词 Urban vegetation STATUS Human impact
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Vegetation and Climate on the Sunda Shelf of the South China Sea During the Last Glactiation-Pollen Results from Station 17962 被引量:12
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作者 孙湘君 李逊 罗运利 《Acta Botanica Sinica》 CSCD 2002年第6期746-752,共7页
This paper presents the pollen data from deep_sea sediments of station 17962 from the continental slope of the southern South China Sea. The 8 m long profile covers the last 30 000 years including the late stage of Ma... This paper presents the pollen data from deep_sea sediments of station 17962 from the continental slope of the southern South China Sea. The 8 m long profile covers the last 30 000 years including the late stage of Marine Oxygen Isotope Stage 3, the Last Glacial Maximum, the Termination and the Holocene. The pollen results reveal that lowland rainforest covered the emerged southern continental shelf of the South China Sea (Sunda Land) during the last glacial period at low sea level stand. At the same time, upper montane rainforest on the adjacent islands expanded, showing the climate was cooler than that in present day, but no dryness was indicated. The vegetation and climate experienced great fluctuations including abrupt warming and cooling at the end of the ice age. During the Holocene, expansion of mangroves and lowland rainforest, and significant diminution of pollen influx values suggests warming of the climate, rising of the sea level and the submerge of the shelf. 展开更多
关键词 South China Sea Sunda Shelf pollen and spores VEGETATION
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Ecological Regionalization of Suitable Trees, Shrubs and Herbages for Vegetation Restoration in the Farming-Pastoral Zone of Northern China 被引量:5
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作者 康慕谊 董世魁 +3 位作者 黄晓霞 熊敏 陈海 张新时 《Acta Botanica Sinica》 CSCD 2003年第10期1157-1165,共9页
To provide materials for the selection of plant species for vegetation restoration and reconstruction in the farming-pastoral zone in northern China, where the eco-environment has been already deteriorated by over-far... To provide materials for the selection of plant species for vegetation restoration and reconstruction in the farming-pastoral zone in northern China, where the eco-environment has been already deteriorated by over-farming and over-grazing, the suitable trees, shrubs and herbages were examined, screened and identified under the guidance of four principles of taking precedence for ecological conservation, being beneficial to economic production, matching species (trees, shrubs and herbages) with the site, and giving consideration to the integrity of local administrative division. According to the key ecological factors that determine species growth and distribution in the zone, i.e., the lowest daily mean temperature in a year, annual accumulated temperature, and water regimes represented by the moist index, the ratio between annual rainfall and accumulated temperature (>0 degreesC), as well as the soil type influenced by climate, surface substances and landform, the farming-pastoral zone was regionalized into seven parts: ( I) Western Songliao Plain and Da Hinggan Mountain Region; (II) Upper Liaohe River Sandy Region; (III) Mid-Eastern Nei Mongol Plateau and Northwestern Heibei Mountain Region; (IV) Luliang, Taihang and Yanshan Mountain Region; ( V) Ordos Plateau Sandy Region; (VI) Northern Shaanxi to Eastern Gansu Loess Plateau Region; and (VII) Mid Gansu to Eastern Qinghai Plateau Loess Region. And the suitable trees, shrubs and herbages for each region were selected and tabularly introduced in detail. 展开更多
关键词 farming-pastoral zone ecological regionalization suitable species for vegetation restoration northern China
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Study on the Characteristics of Main Vegetation Communities in the Limestone Region of Taihang Mountain 被引量:4
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作者 弓运泽 周大迈 任士魁 《Agricultural Science & Technology》 CAS 2011年第12期1932-1936,共5页
[Objective] The aim was to study the characteristics of main vegetation communities in the limestone region of Taihang Mountain,so as to lay foundation for the further improvement of site conditions and the scientific... [Objective] The aim was to study the characteristics of main vegetation communities in the limestone region of Taihang Mountain,so as to lay foundation for the further improvement of site conditions and the scientific breeding of vegetation used to restore the mountain field in limestone region.[Method] Based on the investigation of various vegetation communities in controlled test area,forbidden region and barren hillsides in Daqing Mountain basin,Beishui Valley,Mancheng County,Hebei Province,the difference among controlled region,forbidden region and barren hillsides could be found through data analysis and composite score,and the modes of vegetation communities in controlled region and forbidden region were compared to select predominant species of arbor,shrub and grass in limestone region.[Result] Under the similar site conditions,nutrient content and physical properties of soil in controlled region and forbidden region were superior to those of barren hillsides,and persimmon had high nutrient content and better physical properties compared with oriental arborvitae in controlled region;soil water maintenance and litter characters in controlled region and forbidden region improved more obviously than that of barren hillsides,and shrubbery in forbidden region was the most excellent,arborvitae and persimmon in controlled region the second;the biomass and the coverage rate of vegetation communities in controlled region and forbidden region were higher than those of barren hillsides,and those of shrubbery in forbidden region were better than tussock in closing hill,while persimmon was better than arborvitae in controlled region.The predominant species of arbor,shrub and herbage were obtained through composite score.[Conclusion] From the aspects of soil nutrient,physical properties,soil water maintenance,litter characters,vegetation biomass,canopy density and coverage,controlled region and forbidden region were superior to barren hillsides,and the selection of predominant species of arbor,shrub and herbage considered both ecological and economic benefits. 展开更多
关键词 LIMESTONE Vegetation community Vegetation restoration Preponderant species
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Effect of Water Supply on Seed Germination of Soil Seed-bank in Desert Vegetation 被引量:15
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作者 任珺 陶玲 刘新民 《Acta Botanica Sinica》 CSCD 2002年第1期124-126,共3页
在温室条件下 ,进行了水涝和保湿 2种水分供应试验。结果表明 ,在土壤种子库中 ,有 3种植物的种子在水涝条件下的萌发数量明显较大 ;9种植物在保湿条件下的萌发数量明显较大 ;18种植物在 2种水分供应条件下的萌发数量没有明显差异。当... 在温室条件下 ,进行了水涝和保湿 2种水分供应试验。结果表明 ,在土壤种子库中 ,有 3种植物的种子在水涝条件下的萌发数量明显较大 ;9种植物在保湿条件下的萌发数量明显较大 ;18种植物在 2种水分供应条件下的萌发数量没有明显差异。当植物的土壤种子密度较低时在不太合适的萌发条件下表现为不存在。研究结果强调在进行土壤种子库分析之前预备萌发试验的必要性。同时也揭示出利用一种标准的水分供应处理方法去分析来自不同生境土样里种子库的危险性。 展开更多
关键词 desert vegetation germination characteristics MOISTURE soil seed_bank
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