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Phylogeny and evolution of charophytic algae and land plants 被引量:6
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作者 Yin-Long QIU 《植物分类学报》 CSCD 北大核心 2008年第3期287-306,共20页
Charophytic algae and land plants together make up a monophyletic group, streptophytes, which represents one of the main lineages of multicellular eukaryotes and has contributed greatly to the change of the environmen... Charophytic algae and land plants together make up a monophyletic group, streptophytes, which represents one of the main lineages of multicellular eukaryotes and has contributed greatly to the change of the environment on earth in the Phanerozoic Eon. Significant progress has been made to understand phylogenetic relationships among members of this group by phylogenetic studies of morphological and molecular data over the last twenty-five years. Mesostigma viride is now regarded as among the earliest diverging unicellular organisms in streptophytes. Characeae are the sister group to land plants. Liverworts represent the first diverging lineage of land plants. Hornworts and lycophytes are extant representatives of bryophytes and vascular plants, respectively, when early land plants changed from gametophyte to sporophyte as the dominant generation in the life cycle. Equisetum, Psilotaceae, and ferns constitute the monophyletic group of monilophytes, which are sister to seed plants. Gnetales are related to conifers, not to angiosperms as previously thought. Amborella, Nymphaeales, Hydatellaceae, Illiciales, Trimeniaceae, and Austrobaileya represent the earliest diverging lineages of extant angiosperms. These phylogenetic results, together with recent progress on elucidating genetic and developmental aspects of the plant life cycle, multicellularity, and gravitropism, will facilitate evolutionary developmental studies of these key traits, which will help us to gain mechanistic understanding on how plants adapted to environmental challenges when they colonized the land during one of the major transitions in evolution of life. 展开更多
关键词 系统演化 进化 藻类 陆生植物
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A Transcriptome Atlas of Physcomitrella patens Provides Insights into the Evolution and Development of Land Plants 被引量:3
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作者 Carlos Ortiz-Ramirez Marcela Hernandez-Coronado +5 位作者 Anna Thamm Bruno Catarino Mingyi Wang Liam Dolan Jose A.Feijo Jorg D. Becker 《Molecular Plant》 SCIE CAS CSCD 2016年第2期205-220,共16页
Identifying the genetic mechanisms that underpin the evolution of new organ and tissue systems is an aim of evolutionary developmental biology. Comparative functional genetic studies between angiosperms and bryophytes... Identifying the genetic mechanisms that underpin the evolution of new organ and tissue systems is an aim of evolutionary developmental biology. Comparative functional genetic studies between angiosperms and bryophytes can define those genetic changes that were responsible for developmental innovations. Here, we report the generation of a transcriptome atlas covering most phases in the life cycle of the model bryo- phyte Physcomitrella patens, including detailed sporophyte developmental progression. We identified a comprehensive set of sporophyte-specific transcription factors, and found that many of these genes have homologs in angiosperms that function in developmental processes such as flowering and shoot branching. Deletion of the PpTCP5 transcription factor results in development of supernumerary sporangia attached to a single seta, suggesting that it negatively regulates branching in the moss sporophyte. Given that TCP genes repress branching in angiosperms, we suggest that this activity is ancient. Finally, compar- ison of P. patens and Arabidopsis thaliana transcriptomes led us to the identification of a conserved core of transcription factors expressed in tip-growing cells. We identified modifications in the expression patterns of these genes that could account for developmental differences between P. patens tip-growing cells and A. thaliana pollen tubes and root hairs. 展开更多
关键词 land plant evolution Physcomitrella patens transcriptome atlas TCP branching tip growth
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What are the evolutionary origins of stomatal responses to abscisic acid in land plants? 被引量:4
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作者 Frances C. Sussmilch Timothy J. Brodribb Scott A. M. McAdam 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2017年第4期240-260,共21页
The evolution of active stomatal closure in response to leaf water deficit, mediated by the hormone abscisic acid (ABA), has been the subject of recent debate. Two different models for the timing of the evolution of... The evolution of active stomatal closure in response to leaf water deficit, mediated by the hormone abscisic acid (ABA), has been the subject of recent debate. Two different models for the timing of the evolution of this response recur in the literature. A single-step model for stomatal control suggests that stomata evolved active, ABA- mediated control of stomatal aperture, when these structures first appeared, prior bryophyte and vascular plant gradualistic model for stomatal to the divergence of neages. In contrast, a control proposes that the most basal vascular plant stomata responded passively to changes in leaf water status. This model suggests that active ABA-driven mechanisms for stomatal responses to water status instead evolved after the divergence of seed plants, culminating in the complex, ABA-mediated responses observed in modern angiosperms. Here we review the findings that form the basis for these two models, including recent work that provides critical molecular insights into resolving this intriguing debate, and find strong evidence to support a gradualistic model for stomatal evolution. 展开更多
关键词 ABA What are the evolutionary origins of stomatal responses to abscisic acid in land plants ACID
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Research on Plant Landscape Design in the Reconstruction of Urban Green Land——A Case Study of Green Land Reconstruction of Yangliu River in Wenjiang City of China 被引量:1
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作者 刘维东 张碧芳 《Journal of Landscape Research》 2012年第6期39-41,46,共4页
In modern green land planning, it should highlight the application of native plants and the construction of urban three-dimensional greening. By taking green land reconstruction of Yangliu River of Wenjiang City as an... In modern green land planning, it should highlight the application of native plants and the construction of urban three-dimensional greening. By taking green land reconstruction of Yangliu River of Wenjiang City as an example, the site condition and design concept have been analyzeds; and furthermore, reconstruction schemes have been explained in detail based on five themes. It has emphasized composing landscape based on sections, enriching plant levels, improve forest canopy line and enrich tour space. Plants on green lands can be moved, adjusted, transformed, added and supplemented. 展开更多
关键词 Green land RECONSTRUCTION NATIVE plantS plant landSCAPE RECONSTRUCTION measures
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Sustainable Intensification and Large-scale Operation of Cultivated Land Use at the Farmers’ Scale:A Case Study of Shandong Province,China
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作者 LI Li LYU Xiao +2 位作者 ZHANG Anlu NIU Shandong PENG Wenlong 《Chinese Geographical Science》 SCIE CSCD 2024年第1期149-167,共19页
Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges ... Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges in precisely defining SICLU and constructing comprehensive indicators,which has hindered the exploration of factors influencing LSO within the SICLU framework.To address this gap,we integrated self-efficacy theory into the design of an index framework for evaluating SICLU.We subsequently employed econometric models to analyze the significant factors that impact LSO.Our findings reveal that SICLU can be divided into four key dimensions:intensive management,efficient output,resource conservation,and ecological environment optimization.Furthermore,it is crucial to incorporate belief-based cognitive factors into the index system,as farmers’ understanding of fertilizer and pesticide application significantly influences their willingness to engage in LSO.Moreover,we identify grain market turnover as the most influential factor in promoting LSO,with single-factor contribution rates reaching 70.9% for cultivated land transfer willingness and 62.5% for the total planting areas.Interestingly,unlike irrigation and agricultural machinery inputs,increased labor inputs correspond to larger planting areas for farmers.This trend may be attributed to reduced labor availability because of rural labor migration,whereas the reduction in irrigation and agricultural input is contingent on innovations in production practices and the transfer of cultivated land management rights.Importantly,SICLU dynamically influences LSO,with each index related to SICLU having an optimal range that fosters LSO.These insights offer valuable guidance for policymakers,emphasizing farmers as their central focus,with the adjustment of input and output factors as a means to achieve LSO as the ultimate goal.In conclusion,we propose research avenues for further enriching the SICLU framework to ensure that it aligns with the specific characteristics of regional agricultural development. 展开更多
关键词 sustainable intensification of cultivated land use(SICLU) SELF-EFFICACY status quo bias input and output Boosted Regression Tree willingness to transfer cultivated land cultivated land planting areas Shandong China
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The evolution of Paleozoic vascular land plant diversity of South China 被引量:4
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作者 Yi Wang Jun Wang +1 位作者 HongHe Xu XueZhi He 《Science China Earth Sciences》 SCIE EI CAS 2010年第12期1828-1835,共8页
Data of Paleozoic and some Early Triassic vascular land plant fossils from South China are synthetically analyzed,revealing evolutionary characteristics of Paleozoic vascular land plant diversity.Vascular land plant d... Data of Paleozoic and some Early Triassic vascular land plant fossils from South China are synthetically analyzed,revealing evolutionary characteristics of Paleozoic vascular land plant diversity.Vascular land plant diversity keeps increasing in the Paleozoic as a whole.The Silurian witnessed the earliest evolution and initial diversification of land plants.From the Early Devonian to the Early Carboniferous(Mississippian),the great development,diversification,and differentiation really occurred in vascular land plants,with fluctuations of diversity,rapid replacement of the plant types,and an all-out takeover of terrestrial ecological niches.From the Early Permian,land plant diversity dramatically increased,and reached a climax in the Middle-Late Permian.Comparisons between late Paleozoic marine and terrestrial biodiversity reveal co-evolution of the late Paleozoic animals and plants as well as the individual evolutionary patterns of sea/land ecosystems.Vascular land plant diversity dramatically declined in the Frasnian as a result of the F/F event,and the end-Permian mass extinctions completely turned over the phytogroups. 展开更多
关键词 PALEOZOIC VASCULAR land plants DIVERSITY sea-land CO-EVOLUTION South China
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Effects of rainfall patterns on annual plants in Horqin Sandy Land, Inner Mongolia of China 被引量:8
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作者 YUE Xiangfei ZHANG Tonghui +2 位作者 ZHAO Xueyong LIU Xinping MA Yunhua 《Journal of Arid Land》 SCIE CSCD 2016年第3期389-398,共10页
Growth of annual plants in arid environments depends largely on rainfall pulses. An increased understanding of the effects of different rainfall patterns on plant growth is critical to predicting the potential respons... Growth of annual plants in arid environments depends largely on rainfall pulses. An increased understanding of the effects of different rainfall patterns on plant growth is critical to predicting the potential responses of plants to the changes in rainfall regimes, such as rainfall intensity and duration, and length of dry intervals. In this study, we investigated the effects of different rainfall patterns(e.g. small rainfall event with high frequency and large rainfall event with low frequency) on biomass, growth characteristics and vertical distribution of root biomass of annual plants in Horqin Sandy Land, Inner Mongolia of China during the growing season(from May to August) of 2014. Our results showed that the rainfall patterns, independent of total rainfall amount, exerted strong effects on biomass, characteristics of plant growth and vertical distribution of root biomass. Under a constant amount of total rainfall, the aboveground biomass(AGB), belowground biomass(BGB), plant cover, plant height, and plant individual and species number increased with an increase in rainfall intensity. Changes in rainfall patterns also altered the percentage contribution of species biomass to the total AGB, and the percentage of BGB at different soil layers to the total BGB. Consequently, our results indicated that increased rainfall intensity in future may increase biomass significantly, and also affect the growth characteristics of annual plants. 展开更多
关键词 Horqin Sandy land annual plants rainfall patterns biomass plant growth
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Experimental analysis of a nitrogen removal process simulation of wastewater land treatment under three different wheat planting densities 被引量:2
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作者 WangHQ ChenJJ 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第3期317-324,共8页
Nitrogen contaminant transport, transformation and uptake simulation experiments were conducted in green house under three different planting density of winter wheat. They were Group A, planting density of 0.0208 plan... Nitrogen contaminant transport, transformation and uptake simulation experiments were conducted in green house under three different planting density of winter wheat. They were Group A, planting density of 0.0208 plants/cm 2, Group B, 0.1042 plants /cm 2, and Group C, 0.1415 plants/cm 2. The capacity and ratio of nitrogen removal were different on three kinds of conditions of wastewater land treatment. From analysis of wastewater treatment capacity, wastewater concentration and irrigation intensity for Group C were suitable and nitrogen quantity added was 2 times of that for Group B, 2.6 times for Group A while nitrogen residue was only 7.06%. Hence, wastewater irrigation and treatment design with purpose of waste water treatment should select the design with maximum capacity, optimal removal ratio and least residue in soil, which was closely related to crop planting density, crop growth status and also background nitrogen quantity in soil. 展开更多
关键词 wastewater land treatment planting density winter wheat nitrogen removal SOIL
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Using a Modified Soil-Plant-Atmosphere Scheme(MSPAS)to Simulate the Interaction between Land Surface Processes and Atmospheric Boundary Layer in Semi-Arid Regions 被引量:20
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作者 树华 乐旭 +1 位作者 胡非 刘辉志 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第2期245-259,共15页
This paper uses a Modified Soil-Plant-Atmosphere Scheme (MSPAS) to study the interaction between land surface and atmospheric boundary layer processes. The scheme is composed of two main parts: atmospheric boundary la... This paper uses a Modified Soil-Plant-Atmosphere Scheme (MSPAS) to study the interaction between land surface and atmospheric boundary layer processes. The scheme is composed of two main parts: atmospheric boundary layer processes and land surface processes. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feasibility of the model is well proved in this paper. The numerical simulation results from MSPAS show good agreement with reality. The scheme is used to obtain reasonable simulations for diurnal variations of heat balance, potential temperature of boundary layer, and wind field, and spatial distributions of temperature, specific humidity, vertical velocity, turbulence kinetic energy, and turbulence exchange coefficient over desert and oasis. In addition, MSPAS is used to simulate the interaction between desert and oasis at night, and again it obtains reasonable results. This indicates that MSPAS can be used to study the interaction between land surface processes and the atmospheric boundary layer over various underlying surfaces and can be extended for regional climate and numerical weather prediction study. 展开更多
关键词 modified soil-plant-atmosphere scheme (MSPAS) land surface processes (LSP) atmospheric boundary layer
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Application and Thinking of Right Species for Right Land in Urban Plant Landscaping
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作者 DING Senlin HU Weifeng +1 位作者 GENG Shijun CAI Ping 《Journal of Landscape Research》 2016年第4期107-108,113,共3页
With the acceleration of eco-garden city construction,tree resources have been increasingly applied in landscape construction.Combining with the authors' work experience,plant landscaping cases in domestic and for... With the acceleration of eco-garden city construction,tree resources have been increasingly applied in landscape construction.Combining with the authors' work experience,plant landscaping cases in domestic and foreign cities,this paper analyzed the concept of right species for right land and problems in plant landscaping,and took specific cases to explore the application of right species for right land,in order to provide references for the reasonable utilization of indigenous tree resources. 展开更多
关键词 landscape plant Right species for right land plant landscaping
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Impact of Land Use and Aquatic Plants on the Water Quality of the Sub-Tropical Alpine Wetlands in India: A Case Study Using Neuro-Genetic Models
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作者 Malabika Biswas Roy Pankaj K. Roy +2 位作者 Asis Mazumdar Mrinmoy Majumder Nihar R. Samal 《Journal of Water Resource and Protection》 2012年第8期576-589,共14页
The suspended and dissolved waste in the incoming storm water of wetlands largely depends on the adjacent land use which can influence the quality of the water body. The micro- and macro-floral population of a wetland... The suspended and dissolved waste in the incoming storm water of wetlands largely depends on the adjacent land use which can influence the quality of the water body. The micro- and macro-floral population of a wetland can absorb, convert, transform and release different organic or inorganic elements, which can also change or impact the overall quality of the wetland water. The present study investigates the influence of the land use and the plant species in the waterbed on the water quality of a high-altitude, sub-tropical wetland in India. The estimation capabilities of neuro-genetic models were utilized to identify the inherent relationships between the Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO), chlorine (Cl) and Chemical Oxygen Demand (COD) with the land use and wetland zoology. A thematic map of the quality parameters was also generated based on the identified relationship to observe the influence that the morphological and biological diversity in and around the study area has on the quality parameters of the wetland. According to the results, the BOD, COD and Cl were found to vary with differences in land use and the presence of different plant species, whereas the DO was found to be largely invariant with changes in these parameters. The reasons may be contributed to the impact of uncontrolled eco-tourism activities around the wetland. 展开更多
关键词 WETland Neural Network Water Quality land Use AQUATIC plants
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Vertical distribution of plant nematodes in an aquic brown soil under different land uses 被引量:9
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作者 MENGFan-xiang LiangWen-ju +3 位作者 OUWei JIANGYong LIQi WENDa-zhong 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第1期39-42,i003,共5页
The vertical distribution of the dominant genera of plant nematodes at the depth of 0–150 cm of an aquic brown soil were studied for four land use patterns, i.e., paddy field, maize field, fallow field and woodland i... The vertical distribution of the dominant genera of plant nematodes at the depth of 0–150 cm of an aquic brown soil were studied for four land use patterns, i.e., paddy field, maize field, fallow field and woodland in the Shenyang Experimental Station of Ecology, Chi- nese Academy of Sciences in November of 2003. The results showed that the numbers of some dominant genera under different land uses decreased with the increase of soil depth. Helicotylenchus was most dominant genus under each land use type. Genera of Filenchus, Psilen- chus and Tylenchus in paddy field occurred at the depth of 0–20 cm; while Paratylenchus in fallow field and woodland, as well as Praty- lenchus in maize field presented in the deeper soil layers (0–80 cm). Significant correlations between the numbers of dominant genera of plant nematodes and soil chemical properties were found in this study. The number of Helicotylenchus under different land uses was posi- tively correlated with C/N ratio, total C, total N, total P, alkai-N, and Olsen-P. The numbers of Filenchus and Paratylenchus in paddy field, Pratylenchus in maize field and Paratylenchus in fallow field were negatively correlated with soil pH, and positively correlated with total C, total N and alkai-N. This study results showed that it is essential to sample at a certain depth according to the vertical distribution informa- tion of different genera of plant nematodes in adequately assessing the population size of plant nematodes. 展开更多
关键词 Vertical distribution plant nematodes Dominant genera Aquic brown soil land use
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Layering Precision Land Leveling and Furrow Irrigated Raised Bed Planting: Productivity and Input Use Efficiency of Irrigated Bread Wheat in Indo-Gangetic Plains 被引量:6
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作者 M. L. Jat Raj Gupta +1 位作者 Y. S. Saharawat Raj Khosla 《American Journal of Plant Sciences》 2011年第4期578-588,共11页
Stagnating yield and declining input use efficiency in irrigated wheat of the Indo-Gangetic Plain (IGP) coupled with diminishing availability of water for agriculture is a major concern of food security in South Asia.... Stagnating yield and declining input use efficiency in irrigated wheat of the Indo-Gangetic Plain (IGP) coupled with diminishing availability of water for agriculture is a major concern of food security in South Asia. The objective of our study was to establish an understanding of how wheat yield and input use efficiency can be improved and how land leveling and crop establishment practices can be modified to be more efficient in water use through layering of precision-conservation crop management techniques. The “precision land leveling with raised bed” planting can be used to improve crop yield, water and nutrient use efficiency over the existing “traditional land leveling with flat” planting practices. We conducted a field experiment during 2002-2004 at Modipuram, India to quantify the benefits of alternate land leveling (precision land leveling) and crop establishment (furrow irrigated raised bed planting) techniques alone or in combination (layering precision-conservation) in terms of crop yield, water savings, and nutrient use efficiency of wheat production in IGP. The wheat yield was about 16.6% higher with nearly 50% less irrigation water with layering precision land leveling and raised bed planting compared to traditional practices (traditional land leveling with flat planting). The agronomic (AE) and uptake efficiency (UE) of N, P and K were significantly improved under precision land leveling with raised bed planting technique compared to other practices. 展开更多
关键词 Precision land Leveling FURROW IRRIGATED Raised BED plantING Input Use EFFICIENCY IRRIGATED Bread Wheat Water PRODUCTIVITY Uptake EFFICIENCY Agronomic EFFICIENCY
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Compatibility and complementarity of indigenous and scientific knowledge of wild plants in the highlands of southwest Saudi Arabia 被引量:1
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作者 A.K.Hegazy A.A.Alatar +3 位作者 J.Thomas M.Faisal A.H.Alfarhan K.Krzywinski 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期437-444,共8页
This study presents a survey of wild plants commonly used by local inhabitants in the highlands of southwest Saudi Arabia. Based upon literature review, direct observation of local inhabitants, and questionnaire inter... This study presents a survey of wild plants commonly used by local inhabitants in the highlands of southwest Saudi Arabia. Based upon literature review, direct observation of local inhabitants, and questionnaire interviews, 36 plant species were assessed and given scores according to their use. The gaps between scientific and indigenous knowl- edge on the use of plants were estimated using a "compatibility ratio". The score values were estimated based on seven different use categories of ecosystem services, including food, forage, medicine, wood, beekeeping, research, and education. Additional structural categories include source of materials, shade, hedges, ornamental plantings, and soil stabilization. There are discrepancies between indigenous knowledge (IK) and scien- tific knowledge (SK) but in most cases, SK of the species supports the IK and plant users preference. The results also provide information that challenges assumptions about the consistency of IK with SK. Our study highlights the importance of understanding the cultural context and uses of wild plants. Biodiversity-based knowledge holds promise for contributing to sustainable use of wild plant resources and related traditions. The success of such endeavours depends on the compatibility and complementarity of indigenous and scientific knowledge. 展开更多
关键词 multipurpose use plants importance value compatibility ratio Sarawat mountains arid lands
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基于Landsat-8和Sentinel-2A多光谱影像的陆良县日光温室面积估算 被引量:3
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作者 蒋怡 李宗南 +2 位作者 任国业 王昕 李章成 《西南农业学报》 CSCD 北大核心 2019年第1期179-183,共5页
【目的】选取云南省陆良县,开展基于Landsat-8 OLI和Sentinel-2A MSI影像的设施种植区域监测研究,及时为农业生产管理提供准确的设施农业空间信息。【方法】首先分析日光温室及其他典型地物的遥感特征,然后使用目视解译以及最小距离法... 【目的】选取云南省陆良县,开展基于Landsat-8 OLI和Sentinel-2A MSI影像的设施种植区域监测研究,及时为农业生产管理提供准确的设施农业空间信息。【方法】首先分析日光温室及其他典型地物的遥感特征,然后使用目视解译以及最小距离法、马氏距离法、最大似然法、支持向量机等4种监督分类方法提取设施种植空间信息,再使用亚米级Google earth历史影像为底图建立验证样区。通过目视解译提取样区设施种植区域信息,以此验证Landsat-8和Sentinel-2A影像的监测精度,选择最优监测方法。【结果】使用Landsat-8影像,基于目视解译及4种监督分类方法的精度依次为97. 54%、77. 31%、91. 35%、91. 89%和83. 15%;使用Sentinel-2A影像,基于目视解译及4种监督分类方法的精度依次98. 82%、80. 80%、87. 01%、93. 89%和85. 41%。【结论】①2种影像的日光温室监测均适于使用最大似然法,其估算精度与目视解译精度误差分别为5. 65%和4. 93%;②遥感监测显示,2016年陆良县日光温室主要集中于该县湖积平原区。基于Landsat-8影像监测的面积为5381. 62 hm2,基于Sentinel-2A影像监测的面积为5347. 84 hm2。 展开更多
关键词 土地利用 设施农业 种植面积 遥感 多光谱
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基于Landsat8 OLI与MODIS数据的洪涝季节作物种植结构提取 被引量:25
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作者 陈颖姝 张晓春 +3 位作者 王修贵 罗强 熊勤学 罗文兵 《农业工程学报》 EI CAS CSCD 北大核心 2014年第21期165-173,共9页
洪涝灾害会造成农作物严重受损,因此洪涝季节作物的种植结构是估算洪涝灾害损失、进行防灾减灾措施的必要信息。为了能够快速便捷地提取洪涝季节作物种植结构,该文以湖北省监利县为研究区域,探讨了采用空间分辨率较高的Landsat8陆地成像... 洪涝灾害会造成农作物严重受损,因此洪涝季节作物的种植结构是估算洪涝灾害损失、进行防灾减灾措施的必要信息。为了能够快速便捷地提取洪涝季节作物种植结构,该文以湖北省监利县为研究区域,探讨了采用空间分辨率较高的Landsat8陆地成像仪(operational land imager,OLI)影像和时间分辨率较高的中分辨率成像光谱仪(moderate-resolution imaging spectroradiometer,MODIS)数据,综合利用多源多时相遥感影像提取中小尺度范围的洪涝季节作物种植结构的方法。首先利用MODIS数据建立作物的归一化植被指数(normalized difference vegetation index,NDVI)时间序列曲线,并采用改进后的Savitzky-Golay滤波器对曲线进行平滑处理,然后根据作物的物候特征设定阈值,界定作物种类,进而以此为依据在作物关键生育时期的Landsat8 OLI高清影像中选择合适的感兴趣区域(region of interest,ROI)作为先验知识,使用BP(back propagation)神经网络模型对OLI数据进行监督分类,提取作物种植面积分布。最后利用统计数据与资源三号卫星数据对提取结果进行验证,平均精度达到88%,能够较准确地反映监利县洪涝季节作物的分布情况。该研究可为洪涝灾害损失估算提供可靠基础。 展开更多
关键词 洪涝灾害 遥感 作物 洪涝季节 陆地成像仪 中分辨率成像光谱仪 种植结构
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Research on Plant Diversity of Street Greening in Nanning
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作者 罗庆龙 周琼 +1 位作者 覃文流 黄济文 《Journal of Landscape Research》 2009年第9期65-68,73,共5页
Based on the research of plant diversity of 50 roads and the analysis of the plant species richness and composition,some aspects are compared:the frequency of species occuring,the diversity of evergreen plants and nat... Based on the research of plant diversity of 50 roads and the analysis of the plant species richness and composition,some aspects are compared:the frequency of species occuring,the diversity of evergreen plants and native plants.The ornamental characteristics diversity of plants are analyzed,and the inadequate aspects are proposed to make some countermeasures. 展开更多
关键词 plant DIVERSITY STREET green land Nanning CITY
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Analysis of nutrient content and assessment of economic value for major salt-tolerant plants in coastal areas:a case study of Dongying City, Shandong Province
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作者 Weng Senhong Li Weijiong +1 位作者 Zhang Jiexia Xi Qingguo 《Ecological Economy》 2008年第4期473-483,共11页
Salinization of soil is a worldwide problem concerning resources and ecology,especially serious in coastal areas.Testing of 26 sorts of data or parameters are carried out on leaves of 22 plant species(in 24 plant vari... Salinization of soil is a worldwide problem concerning resources and ecology,especially serious in coastal areas.Testing of 26 sorts of data or parameters are carried out on leaves of 22 plant species(in 24 plant variety) of existing main salt-tolerant plant of the Yellow River Delta region.Data or parameters include the following ele-ments:contents of K+,Na+,Ca2+,Mg2+ and Cl-,contents of protein,fat,total energy,ash and contents of 17 amino acids.The results show that these tested plants have economic values.For example,according to their uses,they can be divided into edible plants,forage plants,medicine or health plants,and some of them can be used for multipurposes.These plants have played important roles in the sustainable utilization of plant resources in coastal areas.This paper has taken evaluations on the economic uses of salt-tolerant plants and given suggestions for saline soil improvement and resource utilization in coastal areas.Based on the results of investigation and experiments,we suppose that the salt-tolerant plants in coastal areas can be grouped into 9 main groups according to their economic value:pioneer plants for saline land improvement,medicine,edible and forage plants,industry material,forestation,breeding material,energy plants and eco-tourism resources. 展开更多
关键词 Coastal saline land Salt-tolerant plant Economic value
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基于MaxEnt模型的陕西省菊芋种植潜在适宜区分析 被引量:2
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作者 尹芳 朱家政 +1 位作者 孟文睿 金子悦 《中国农业气象》 CSCD 2024年第3期268-280,共13页
利用陕西省29个菊芋空间分布数据和26个环境因子,综合陕西省边际土地分布,运用最大熵模型(MaxEnt)模拟历史时期及未来气候变化下陕西省菊芋潜在适宜区分布,并将结果叠加陕西省现有边际土地进行分析。结果表明:(1)MaxEnt模型模拟陕西省... 利用陕西省29个菊芋空间分布数据和26个环境因子,综合陕西省边际土地分布,运用最大熵模型(MaxEnt)模拟历史时期及未来气候变化下陕西省菊芋潜在适宜区分布,并将结果叠加陕西省现有边际土地进行分析。结果表明:(1)MaxEnt模型模拟陕西省菊芋种植潜在适宜区结果精度较高,曲线下面积AUC为0.914。(2)基于历史时期环境数据,陕西省菊芋潜在分布区主要分布在榆林定边县、延安志丹县、安康汉滨区、商洛商州区和汉中西乡县,边际土地总适宜区面积约为75992km^(2),占陕西省总面积的36.9%,其中低、中、高适宜性面积分别约为63169、11617和1205km^(2),主要边际土地利用类型为中覆盖度草地。(3)影响菊芋生长的5个重要环境因子为土壤深度(142.4~155.4cm)、最暖月最高气温(29.4~31.6℃)、高程(210~593m)、坡向(70.7°~239.5°)和坡度(0~10.5°)。(4)未来4种气候情景模式下陕西省菊芋种植中、高适宜区面积总体明显增加,2021-2040年分别增加14.39%~46.46%和46.90%~95.39%,2041-2060年分别增加15.95%~71.52%和48.46%~111.40%。未来气候变化有助于陕西菊芋适宜种植区扩大,建议在榆林定边县、商洛商州区等高适宜地区开展种植实验,验证菊芋对当地环境的适宜性,探索推广培育的可行性。 展开更多
关键词 边际土地 能源作物 菊芋 适宜性分析 气候变化
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Implications of crude oil pollution on natural regeneration of plant species in an oil-producing community in the Niger Delta Region of Nigeria
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作者 U.D Chima G.Vure 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第4期915-921,共7页
The study evaluated the impact of crude oil pollution on natu- ral regeneration of plant species in a major oil-producing community in the Niger Delta region of Nigeria. Three sites--unpolluted site (US), polluted a... The study evaluated the impact of crude oil pollution on natu- ral regeneration of plant species in a major oil-producing community in the Niger Delta region of Nigeria. Three sites--unpolluted site (US), polluted and untreated site (PUS), and polluted and treated site (PTS)-- were purposively chosen for the study. The seedling emergence method was used to evaluate soil seed banks in the various sites at two depths, 0 to 10 cm and 10 to 20 cm. Woody-plant species richness, abundance, and diversity were higher in the US seed bank than in the PUS and PTS seed banks. The highest number of non-woody plants was observed in the US, followed by the PTS, and then the PUS. Both species richness and diversity of non-woody plants were highest at the US, followed by the PUS, and lowest in the PTS. Woody species in the US seed bank were 87.5% and 80% dissimilar with those of the PUS and PTS at 0-10 cm and 10--20 cm respectively. No variation was observed between woody species in the PUS and PTS seed banks. Non-woody species at 0-10 em US seed bank were 73.08% dissimilar with those of PUS at the two soil depths and 81.48/88.46% dissimilar with those of the 0-10/10-20 cm of the PTS respectively. At 10-20 cm, non-woody species of theUS were 69.66% dissimilar with those from each of the two soil depths in PUS; and 73.91/81.82% dissimilar with those of 0-10/10-20 cm of the PTS respectively. Non-woody species variation between the PUS and PTS was higher at 10-20 cm than 0-10 cm. The poor seed bank attributes at the polluted sites demonstrates that crude oil pollution negatively af- fected the natural regeneration potential of the native flora because soil seed banks serve as the building blocks for plant succession. Thorough remediation and enrichment planting are recommended to support the recovery process of vegetation in the polluted areas. 展开更多
关键词 Ogoni land crude oil pollution REMEDIATION plant regeneration
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