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Element cycling in the dominant plant community in the Alpine tundra zone of Changbai Mountains, China 被引量:5
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作者 LIUJing-shuang YUJun-bao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第3期521-525,共5页
Element cycling in the dominant plant communities including Rh. aureum, Rh. redowskianum and Vaccinium uliginosum in the Alpine tundra zone of Changbai Mountains in northeast China was studied. The results indicate th... Element cycling in the dominant plant communities including Rh. aureum, Rh. redowskianum and Vaccinium uliginosum in the Alpine tundra zone of Changbai Mountains in northeast China was studied. The results indicate that the amount of elements from litter decomposition was less than that of the plant uptake from soil, but that from plant uptake was higher than that in soil with mineralization process released. On the other hand, in the open system including precipitation input and soil leaching output, because of great number of elements from precipitation into the open system, the element cycling(except N, P) in the Alpine tundra ecosystem was in a dynamic balance. In this study, it was also found that different organ of plants had significant difference in accumulating elements. Ca, Mg, P and N were accumulated more obviously in leaves, while Fe was in roots. The degree of concentration of elements in different tissues of the same organ of the plants also was different, a higher concentration of Ca, Mg, P and N in mesophyll than in nerve but Fe was in a reversed order. The phenomenon indicates (1) a variety of biochemical functions of different elements, (2) the elements in mesophyll were with a shorter turnover period than those in nerve or fibre, but higher utilization rate for plant. Therefore, this study implies the significance of keeping element dynamic balance in the alpine tundra ecosystem of Changbai Mountains. 展开更多
关键词 element cycling ECOSYSTEM dominant plant community alpine tundra zone Changbai Mountains
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Spatial variations of Pb in the vertical zone of the soil-plant system in the Changbai Mountain National Nature Reserve
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作者 BaiJH DengW 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第3期325-329,共5页
The characteristics of vertical and horizontal variations of lead element(Pb) in soil plant system of vertical zone in Changbai Mountain National Nature Reserve(CNNR) were studied. The results showed that Pb concentr... The characteristics of vertical and horizontal variations of lead element(Pb) in soil plant system of vertical zone in Changbai Mountain National Nature Reserve(CNNR) were studied. The results showed that Pb concentrations in soils of vertical zone are all above 25 mg/kg, and the average Pb concentration of each soil zone negatively correlates its degree of variation, i.e. brown coniferous forest soil zone has the lowest average Pb concentration of four soil zones, and the highest horizontal variation; however, mountain soddy forest soil has the highest average Pb concentration, and the lowest horizontal variation; the average concentration of plant Pb of each plant zone is lower than the worldwide average level of Pb in plant(Clarke), respectively, and plant Pb content order is consistent with soil Pb content order, but their horizontal variations are different from those in soil zones, the variation of mountain tundra forest zone is highest, but Betula ermanii forest zone the lowest. Vertical variation of plant Pb is obviously higher than that in soils with variation coefficient of 89.76%; the enrichment capability of plant for Pb is depended on the plant types and the different organs of plant; parent material and parent rock, pH values, soil organic matter and soil particle fraction etc. are the main factors influencing variations of Pb content in soil plant system of vertical zone in CNNR. 展开更多
关键词 PB variation characteristics soil plant system vertical zone Changbai Mountain National Nature Reserve
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Computer-aided system for hazard zone identification in ship power plants
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作者 PODSIADLOA TARELKOW 《上海海事大学学报》 北大核心 2005年第3期22-28,共7页
The most dangerous places in ships are their power plants. Particularly, they are very unsafe for operators carrying out various necessary operation and maintenance activities. For this reason, ship machinery should b... The most dangerous places in ships are their power plants. Particularly, they are very unsafe for operators carrying out various necessary operation and maintenance activities. For this reason, ship machinery should be designed to ensure the maximum safety for its operators. It is a very difficult task. Therefore, it could not be solved by means of conventional design methods, which are used for design of uncomplicated technical equipment. One of the possible ways of solving this problem is to provide appropriate tools, which allow us to take the operator's safety into account during a design process, especially at its early stages. A computer-aided system supporting design of safe ship power plants could be such a tool. This paper deals with developing process of a prototype of the computer-aided system for hazard zone identification in ship power plants. 展开更多
关键词 船舶 计算机控制系统 安全性 操控性 动力系统
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Plant diversity and its maintenance in Populus euphratica riparian forests in the Ejina Oasis,China 被引量:2
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作者 ZHOU Wei-lei YANG Xue-qin +4 位作者 HAO Peng LIU Qian-wen CAO De-chang Tom BARIBAULT LI Jing-wen 《Forestry Studies in China》 CAS 2010年第2期55-61,共7页
The dynamic environments in riparian zones support a variety of life-history strategies, which constitute a fundamental mechanism for development and maintenance of biodiversity in riparian forest ecosystems. To demon... The dynamic environments in riparian zones support a variety of life-history strategies, which constitute a fundamental mechanism for development and maintenance of biodiversity in riparian forest ecosystems. To demonstrate the effect of life-history strategies on biodiversity, we investigated community-level diversity and its relationship to environmental variability in the riparian Populus euphratica forests of the Ejina Oasis. Communities were divided into 14 associations on the basis of their species impor- tance values. The Simpson's index, Shannon-Wiener index, Pielou's evenness index and the regional Whittaker's index were applied to calculate community diversity. An ordination of the sample plots was carried out by correspondence analysis (CA). Biodiversity was relatively low across the entire study area, but there was high community diversity (flw = 8.09) due to the spatial heterogeneity of habitats in different plots. In addition, we investigated the relationship between biodiversity and several environmental factors, such as water availability, community components and soil conditions. We conclude that the heterogeneity of soil and water availability drives community diversity patterns in riparian zones and that community-level diversity favors the maintenance of species diversity in the P euphratica forests in the Ejina Oasis. 展开更多
关键词 plant diversity riparian zones maintenance mechanism Populus euphratica Ejina Oasis
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Medicinal Plants, A promising Source of Natural Fungicides against <i>Magnaporthe oryzae Triticum</i>, Causal Agent of Wheat Blast 被引量:1
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作者 Abul Hasnat Md. Shamim 《American Journal of Plant Sciences》 2021年第5期748-758,共11页
Wheat blast, caused by a fungal pathogen, <i><span style="font-family:Verdana;">Magnaporthe oryzae Tritichum </span></i><span style="font-family:Verdana;">(</span&g... Wheat blast, caused by a fungal pathogen, <i><span style="font-family:Verdana;">Magnaporthe oryzae Tritichum </span></i><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">MoT</span></i><span style="font-family:Verdana;">) pathotype (wheat isolates), was first reported in Bangladesh among Asian countries in 2016. It is a serious disease of wheat causing yield failures and significant economic losses during epidemic years. Extensive use of persistent synthetic pesticides to control notorious wheat blast imposes enormous threat to human health and environment. In addition, the increasing demand for organic food has stimulated people to look for alternative methods. Nowadays, the need for synthetic chemical-free agricultural practices is gaining importance due to effective in managing crop pests, inexpensive, biodegradable, easily available and have low toxicity to non-target organisms. In order to identify active plants, 12 kinds of methanol extracts obtained from 12 medicinal plants were conducted </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> to test the effect against </span><i><span style="font-family:Verdana;">Magnaporthe oryzae Triticum </span></i><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">MoT</span></i><span style="font-family:Verdana;">) pathotype. The remarkable inhibitory activity {(29.6 ± 01.5) mm, (25.1 ± 01.0) mm and (20.0 ± 02.0) mm zone of inhibition)} exhibited by the extracts (5 mg/disk) obtained from </span><i><span style="font-family:Verdana;">Artemisia indica</span></i><span style="font-family:Verdana;"> (Nagdona), </span><i><span style="font-family:Verdana;">Persicaria orientalis</span></i><span style="font-family:Verdana;"> (Bishkatali) and </span><i><span style="font-family:Verdana;">Clerodendrum indicum</span></i><span style="font-family:Verdana;"> (Bamonhati), respectively. Other medicinal plant extracts did not show any significant or no activity at all. Therefore, the three plant extracts might be a promising source for developing natural fungicides against wheat blast.</span> 展开更多
关键词 Medicinal plants EXTRACTS Activity Fungicides zone of Inhibition Wheat Blast
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Effect of Thermal Discharge of Cool Water Outfall from Liquefied Natural Gas (LNG) Plant into Sea Using CORMIX 被引量:1
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作者 Shivangi Nigam B. Padma S. Rao A. Srivastava 《Journal of Computer and Communications》 2013年第4期1-5,共5页
The numerical modeling for the cool water outfall discharge from the LNG Plant is undertaken using CORMIX to evaluate the design of diffuser for discharge. The hydrodynamic data tide and currents are used inputs to th... The numerical modeling for the cool water outfall discharge from the LNG Plant is undertaken using CORMIX to evaluate the design of diffuser for discharge. The hydrodynamic data tide and currents are used inputs to the model. It is then calibrated using monitored data. The software has been run to calculate the mixing zone and dilution patterns for various flow conditions. Model result shows that ambient condition is achieved within 64 m from the proposed outfall locations. From the results of the modeling studies it can be concluded that the proposed diffuser design and outfall locations are suitable for all tide conditions. It also shows that there is no significant impact on the marine life due to the proposed cool water discharge, beyond the small area around the discharge location, as the parameters are attaining near ambient water quality within the acceptable space and time. 展开更多
关键词 CORMIX MIXING zone OUTFALL LNG plant HYDRODYNAMIC Model
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猪毛菜响应干旱胁迫的叶片结构、生理及转录组分析 被引量:3
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作者 谭炯锐 查同刚 +6 位作者 张泽宇 张晓霞 滕红梅 王玲丽 赵莉丽 王奥 王馨珧 《草业学报》 CSCD 北大核心 2024年第1期75-88,共14页
为探究猪毛菜在表型、生理及分子层面对干旱胁迫的响应机制,采用控水法进行梯度干旱胁迫,对叶片进行解剖结构和生理指标测定及转录组测序。结果表明:干旱胁迫导致栅栏组织从致密变稀疏,晶簇先消失后增多;贮水组织厚度先增大后降低(P<... 为探究猪毛菜在表型、生理及分子层面对干旱胁迫的响应机制,采用控水法进行梯度干旱胁迫,对叶片进行解剖结构和生理指标测定及转录组测序。结果表明:干旱胁迫导致栅栏组织从致密变稀疏,晶簇先消失后增多;贮水组织厚度先增大后降低(P<0.05),主维管束面积和表皮厚度在28 d时显著增大,分别为(3099.72±151.88)μm^(2)和(23.73±0.68)μm(P<0.05),叶片厚度增大而叶面积减小(P<0.05);叶绿素含量逐渐降低(P<0.05),超氧化物歧化酶(SOD)和过氧化物酶(POD)活性、脯氨酸和丙二醛(MDA)含量在28 d显著增大(P<0.05),H2O2含量在14 d显著增大(P<0.05),可溶性蛋白含量先增后降再增(P<0.05)。与0 d比较,干旱胁迫7、14和28 d的差异表达基因(DEGs)分别有103、1560和270个;基因本体(GO)富集分析表明各组合DEGs显著富集在蛋白质磷酸酶Ⅰ型复合体、膜的整体组件、氧化还原过程、氧化还原酶活性等条目中;京都基因与基因组百科全书(KEGG)富集分析表明各组合DEGs同时显著富集在氧化磷酸化代谢、核糖体和光传导等通路中。非生物胁迫通路DEGs分析表明,热激蛋白基因、GPX2、POD、SOD、CPK19、CIPK9、MAP激酶基因、蛋白质降解通路基因、UXS1和F3H等参与对干旱胁迫的响应调节。研究结果可为进一步研究猪毛菜抗旱机制提供参考。 展开更多
关键词 干旱区植物 胁迫 解剖结构 生理特性 分子调控
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Tsunami Impacts on Nuclear Power Plants along Western Coast of India Due to a Great Makran Earthquake: A Numerical Simulation Approach
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作者 Mohd Zuhair Shahnawaz Alam 《International Journal of Geosciences》 2017年第12期1417-1426,共10页
The major seismicity source in the northern Arabian Sea is the Makran Subduction Zone (MSZ) that defines the tectonic boundary between the Arabian plate and the Eurasian plate, located offshore Iran and Pakistan over ... The major seismicity source in the northern Arabian Sea is the Makran Subduction Zone (MSZ) that defines the tectonic boundary between the Arabian plate and the Eurasian plate, located offshore Iran and Pakistan over which an instrumentally registered earthquake (Mw 8.1) generated a tsunami on 27 November, 1945. It has caused severe cataclysm to a vulnerable population along the surrounding coastlines, including India. It has been on a long seismic quiescence since this last event. The population and industrialization have exponentially increased along the coastal areas in last half decade. The highly exposed coastal locations to the tsunamis are the areas where the nuclear power plants are located. In the present work, a numerical simulation of a great tsunamigenic earthquake (M 9) is presented that predicts the generation, propagation, run-up and travel time using TUNAMI N2 for estimating tsunami impacts along the nuclear power plants of the western coast of India. TUNAMI N2 code was designed for shallow water wave equations, which uses the finite-difference method based on staggered-leap frog scheme. Thus, it has potential to simulate a far-field tsunami with much more accuracy than other methods. It is observed that the tsunami will strike along the coast of Jaitapur Nuclear Power Plant (Maharashtra), Tarapur Nuclear Power Plant (Maharashtra), Kaiga Nuclear Power Plant (Karnataka) and Mithi-Virdi Nuclear Power Plant (Gujarat) after 210, 215, 225 and 230 minutes, respectively. Results show that the tsunami run-up is highest for Jaitapur coast (2.32 m). The Mithi-Virdi coast is the least effected (0.93 m) while Kaiga (2.15 m) and Tarapur coast (2.12 m) might have faced quite intense tsunami consequences. The arrival times and run-ups of the tsunami along the coast of different power plants have been calculated since these parameters are of vital importance in mitigation of the coastal hazard, evacuation planning and installation of early warning system in order to save the inhabited communities from the disaster. 展开更多
关键词 TSUNAMI Modeling TUNAMI N2 Nuclear Power plants MAKRAN SUBDUCTION zone
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Choice of Site for the Installation of Photovoltaic Solar Power Plants in Senegal: Consequences on Electricity Production 被引量:1
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作者 Mactar Faye Ababacar Thiam 《Journal of Power and Energy Engineering》 2017年第12期109-118,共10页
A theoretical analysis of the electricity production of a photovoltaic solar power plant of 22 MW for different sites in Senegal is presented. The study is carried out in two coastal regions (Dakar and Saint-Louis) an... A theoretical analysis of the electricity production of a photovoltaic solar power plant of 22 MW for different sites in Senegal is presented. The study is carried out in two coastal regions (Dakar and Saint-Louis) and two continental regions (Mbacké and Linguère). This study is done using the RET Screen clean energy project management software climate data. The amount of electricity exported to the grid is calculated for each site. The results show that the climatic conditions of the coastal and continental regions are different from November to June. From July to October, which corresponds to the rainy season in Senegal, the climatic conditions of the coastal and continental regions are similar. The results also show that although the efficiency of photovoltaic modules is better on the coast, electricity production varies little from one site to another. Climate conditions in Senegal therefore have no impact on electricity production. 展开更多
关键词 PHOTOVOLTAIC Solar Power plant CLIMATIC Conditions Electricity Production COASTAL zone CONTINENTAL zone
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Stem flow of seed-maize under alternate furrow irrigation and double-row ridge planting in an arid region of Northwest China 被引量:3
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作者 BO Xiao-dong DU Tai-sheng +2 位作者 DING Ri-sheng TONG Ling LI Si-en 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第7期1434-1445,共12页
Maize is widely planted throughout the world and has the highest yield of all the cereal crops. The arid region of North- west China has become the largest base for seed-maize production, but water shortage is the bot... Maize is widely planted throughout the world and has the highest yield of all the cereal crops. The arid region of North- west China has become the largest base for seed-maize production, but water shortage is the bottleneck for its long-term sustainability. Investigating the transpiration of seed-maize plants will offer valuable information for suitable planting and irrigation strategies in this arid area. In this study, stem flow was measured using a heat balance method under alternate furrow irrigation and double-row ridge planting. Meteorological factors, soil water content (e), soil temperature (Ts) and leaf area (LA) were also monitored during 2012 and 2013. The diurnal stem flow and seasonal dynamics of maize plants in the zones of south side female parent (SFP), north side female parent (NFP) and male parent (MP) were investigated. The order of stem flow rate was: SFP〉MP〉NFP. The relationships between stem flow and influential factors during three growth stages at different time scales were analyzed. On an hourly scale, solar radiation (Rs) was the main driving factor of stem flow. The influence of air temperature (Ta) during the maturity stage was significantly higher than in other periods. On a daily scale, Rs was the main driving factor of stem flow during the heading stage. During the filling growth stage, the main driving factor of NFP and MP stem flow was RH and Ts, respectively. However, during the maturity stage, the environ- mental factors had no significant influence on seed-maize stem flow. For different seed-maize plants, the main influential factors were different in each of the three growing seasons. Therefore, we identified them to accurately model the FP and MP stem flow and applied precision irrigation under alternate partial root-zone furrow irrigation to analyze major factors affecting stem flow in different scales. 展开更多
关键词 stem flow alternate partial root-zone furrow irrigation double-row ridge planting seed-maize
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黑龙江省种植模式区划研究
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作者 杜国明 马尚荣 +1 位作者 张瑞 关国锋 《东北农业大学学报》 CAS CSCD 北大核心 2024年第2期81-92,共12页
合理构建黑龙江省种植模式区划,对优化耕作制度、促进农业高质量发展、推进黑土地保护具有重要意义。基于地学信息图谱识别种植模式类型,选取作物生育期平均气温、作物生育期平均湿润指数、地貌类型、种植模式4项指标构建区划指标体系,... 合理构建黑龙江省种植模式区划,对优化耕作制度、促进农业高质量发展、推进黑土地保护具有重要意义。基于地学信息图谱识别种植模式类型,选取作物生育期平均气温、作物生育期平均湿润指数、地貌类型、种植模式4项指标构建区划指标体系,以县级地域单元为区划的基本单元,采用聚类分析、叠置法两种定量区划方法,拟定黑龙江省种植模式区划方案。结果表明,黑龙江省种植模式可分为玉米连作、水稻连作、大豆连作、米豆轮作、混合模式五种类型,面积占比分别为27.91%、23.11%、10.40%、21.50%、17.08%,空间分异特征显著。黑龙江省县级地域单元种植模式结构多样,可分为14种类型。其中,以种植模式结构单一型为主,种植模式结构单一型与种植模式结构混合型占比分别为69.84%、30.16%。黑龙江省划分为8个种植模式区,各区种植模式因水热条件、地貌条件差异表现出地域分异规律,文章针对各区存在问题提出相应对策建议。 展开更多
关键词 黑龙江省 种植模式 区划 聚类分析
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黄河中下游过渡区河岸植物多样性与土壤因子的关系
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作者 梁少民 吕宇豪 +1 位作者 李雅 吕金岭 《西北植物学报》 CAS CSCD 北大核心 2024年第6期968-976,共9页
[目的]河岸带物种多样性与土壤因子的关系对维持河岸带生态系统的稳定性十分重要,为揭示黄河中下游河岸带物种多样性与土壤因子的关系,进一步为黄河中下游过渡区河岸生态恢复、保护和高质量发展提供一定的参考与理论指导。[方法]采用样... [目的]河岸带物种多样性与土壤因子的关系对维持河岸带生态系统的稳定性十分重要,为揭示黄河中下游河岸带物种多样性与土壤因子的关系,进一步为黄河中下游过渡区河岸生态恢复、保护和高质量发展提供一定的参考与理论指导。[方法]采用样方调查法、试验分析法、CCA排序法等方法,以河南黄河中下游过渡区对植物分布和物种多样性与土壤因子的关系进行研究。[结果](1)黄河中下游过渡区河岸有机质、速效钾及有效磷均属于中等变异程度,土壤含水量、全氮变异系数为强变异性,土壤养分空间分布总体呈现中度不均匀的特征。(2)黄河中下游过渡区河岸植物优势度指数(D)与土壤全氮具有显著负相关关系(P<0.05);土壤pH值、速效钾和有效磷对物种丰富度指数(S)的影响不明显;均匀度指数(E)、香农-威纳指数(H)与6个土壤因子之间均没有达到显著水平。(3)红蓼、头状穗莎草、长芒稗、糠稷、醴肠群落的分布受土壤含水量的影响较大;青蒿、酸枣、毛白杨等的分布主要受全氮的影响较大,在全氮含量较高的区域分布较多;葎草和反枝苋受速效钾影响较大;而狗牙根、苍耳、芦苇、狗尾草、春蓼、绿豆等群落受土壤因子的影响较小。[结论]黄河中下游过渡区河岸带土壤含水量、速效钾及全氮是影响植物分布的主要因子,不同植物对土壤条件的需求存在差异,能够直观反映出植被与土壤环境之间的关系。 展开更多
关键词 黄河中下游过渡区 河岸带 植物群落 物种多样性 土壤因子
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Status Survey on Street Trees in Donghu Hi-tech Development Zone in Wuhan City
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作者 戢小梅 谭庆 +2 位作者 陈法志 童俊 金莉 《Journal of Landscape Research》 2009年第7期40-43,53,共5页
Through typical sampling,the species,diameters at breast height (DBH) and growth status of street trees in Donghu Hi-tech Development Zone in Wuhan City were investigated;the characteristics and existing problems were... Through typical sampling,the species,diameters at breast height (DBH) and growth status of street trees in Donghu Hi-tech Development Zone in Wuhan City were investigated;the characteristics and existing problems were analyzed.Constructive suggestions were put forward to enrich urban street tree species and outstand the characteristics of local species,so as to provide references to the street tree planning in Donghu Hi-tech Development Zone in Wuhan City. 展开更多
关键词 STREET trees plant SPECIES Characteristics Donghu HI-TECH Development zone in WUHAN CITY
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利用盐生植物发展“盐湖农业”研究进展 被引量:1
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作者 孔凡晶 王现洁 王利伟 《地球学报》 CAS CSCD 北大核心 2024年第5期815-822,共8页
由于人口增长和全球气候变暖,次生土壤盐碱化日趋严重,淡水资源缺乏,使得人类粮食和食品供给面临严峻挑战。“盐湖农业”为解决这一问题提供了一种新的思路。本文评述了盐生植物在农业上的应用国内外研究进展,重点综述了盐生植物作为食... 由于人口增长和全球气候变暖,次生土壤盐碱化日趋严重,淡水资源缺乏,使得人类粮食和食品供给面临严峻挑战。“盐湖农业”为解决这一问题提供了一种新的思路。本文评述了盐生植物在农业上的应用国内外研究进展,重点综述了盐生植物作为食物、饲料、工业原料等方面的研究。盐生植物生长环境比较恶劣,一些盐生植物为应对逆境环境而合成出丰富的次生代谢物,这些代谢物对预防疾病和促进健康大有益处,因此近年来市场对盐生植物的需求显著增加。我国盐湖资源丰富,利用盐生植物发展盐湖农业有得天独厚的条件,具有广阔的应用前景,本文最后提出了在我国发展盐湖农业的几点建议。 展开更多
关键词 盐湖农业 耐盐植物 咸水资源 盐碱地 盐沼带 盐生植物
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广西滨海植物区系特征
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作者 林建勇 姜冬冬 潘良浩 《福建林业科技》 2024年第2期130-137,共8页
根据2021—2023年的野外调查和资料整理,对广西滨海植物的区系组成、区系地理成分、生长型和特有性进行统计分析;采用浪花飞溅区植物的概念,提出滨海植物划分的新方法。结果表明:(1)广西滨海植物共有1038种,隶属于159科637属,其中蕨类植... 根据2021—2023年的野外调查和资料整理,对广西滨海植物的区系组成、区系地理成分、生长型和特有性进行统计分析;采用浪花飞溅区植物的概念,提出滨海植物划分的新方法。结果表明:(1)广西滨海植物共有1038种,隶属于159科637属,其中蕨类植物12科22属33种,裸子植物7科8属13种,被子植物140科607属992种;野生植物133科505属803种,栽培植物83科177属235种。生活型以草本种类最多,有437种,占比达42.10%;而藤本植物最少,只有133种,占12.81%。(2)外来入侵种共有66种,占广西野生滨海植物种数8.22%,其中属于国家重点管理的外来入侵种14种。(3)广西滨海植物区系具有明显的热带-亚热带性质,温带地理成分比例小,表现出热带北缘区系的特点;与广东省的关系最近,两地共有种占广西野生滨海植物种数的91.41%;广西滨海植物缺乏特有种,仅有1种,即谢氏膝柄木(Bhesa xiei)。(4)重点保护种类较多,有国家一级重点保护野生植物2种,国家二级重点保护野生植物5种,广西重点保护野生植物2种。 展开更多
关键词 滨海植物 植物区系 红树植物 浪花飞溅区 广西
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中国河湖岸带草本植物氮磷化学计量学及内稳性特征
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作者 杨恒 张丹 +3 位作者 李桂芳 叶远行 陈清飞 王蓉 《生态科学》 CSCD 北大核心 2024年第2期78-86,共9页
河湖岸带是拦截净化氮磷等陆源污染物进入河湖水体的最后屏障,河湖岸带草本植物的稳定性影响着其对污染物的拦截净化能力,研究河湖岸带草本植物生态化学计量学及内稳性,可为河湖岸带草本植物群落恢复和构建提供基础数据。通过对中国河... 河湖岸带是拦截净化氮磷等陆源污染物进入河湖水体的最后屏障,河湖岸带草本植物的稳定性影响着其对污染物的拦截净化能力,研究河湖岸带草本植物生态化学计量学及内稳性,可为河湖岸带草本植物群落恢复和构建提供基础数据。通过对中国河湖岸带草本植物地上部氮(N)、磷(P)含量及土壤或沉积物、水体进行数据收集,分析了植物氮磷化学计量学和内稳性特征及其与环境因子的关系。结果表明:青藏高原湖区草本植物具有较高的N含量(湿生植物:20.51 g·kg^(-1),水生植物:29.81 g·kg^(-1))和较低的P含量(湿生植物:1.39 g·kg^(-1),水生植物:0.99 g·kg^(-1)),N:P>14,表现为P限制,而其他湖区草本植物具有较高的P含量(2.73 g·kg^(-1)),N:P<14,表现为N限制。各湖区植物N、P含量及其比值在空间上具有一定差异,青藏高原湖区水生植物N含量最高,东北平原与山地湖区最低(P<0.05);东北平原与山地湖区湿生和水生植物P含量最高(P<0.05);青藏高原湖区湿生和水生植物N:P最高,东北平原与山地湖区最低(P<0.05)。植物N、P含量及N:P受环境中P含量影响最大,其次是环境中N:P和N含量。内稳性模型表明河湖岸带草本植物属于稳态型,其中湿生植物内稳性指数HN、HP及HN:P大于水生植物,表明水生植物受环境胁迫时响应较大,水生和湿生植物对环境中N、P含量变化响应的差异表明水生和湿生植物对环境中N、P不同的保守利用策略。 展开更多
关键词 生态化学计量学 内稳性 氮磷 草本植物 河湖岸带
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半干旱风沙草原区盐湖植物防护体系土壤理化性状特征 被引量:1
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作者 郭靖捷 任晓萌 +5 位作者 蒙仲举 王涛 祁帅 宋佳佳 宝孟克那顺 韩胜利 《中国农业科技导报》 CSCD 北大核心 2024年第1期182-192,共11页
为探究植物防护措施对半干旱风沙草原区土壤的改良效应,以查干淖尔盐湖植物防护体系为研究对象,采用野外调查结合室内试验的方法,测定不同区域土壤理化性质,分析0—30 cm深度土壤含盐量、土壤酸碱度、土壤粒径组成、土壤有机质和氮磷钾... 为探究植物防护措施对半干旱风沙草原区土壤的改良效应,以查干淖尔盐湖植物防护体系为研究对象,采用野外调查结合室内试验的方法,测定不同区域土壤理化性质,分析0—30 cm深度土壤含盐量、土壤酸碱度、土壤粒径组成、土壤有机质和氮磷钾含量的变化。结果表明,查干淖尔盐湖植物防护体系营造建设20年后,在防护带阻挡风蚀物质和植物改善土壤的协同作用下,原有高盐强碱土壤环境出现了显著变化。与干涸湖心相比,植物防护体系内各样地pH均有不同程度的降低,碱蓬防护带内土壤含盐量降低75.34%;碱蓬防护带内土壤粘粒和粉粒含量增幅明显,较干涸湖心分别增加51.60%和22.14%,粗砂含量较干涸湖心降低72.06%;碱蓬防护带内土壤速效钾、速效磷、有机质含量较高,分别是干涸湖心的86%、39%、55%;过渡带白刺灌丛速效氮含量较高,为干涸湖心的28%。总体上各养分含量与粘粒和粉粒呈显著相关(P<0.05)。历经20年的营建,碱蓬防护带内土壤速效钾、速效磷、有机质含量较建设初期明显增长,表明植物防护体系对土壤具有明显的改良作用。研究成果为盐湖植物防护体系防护效应评价提供数据支撑,并为半干旱风沙草原区干涸盐湖风蚀控制和区域植被恢复重建提供科学依据。 展开更多
关键词 半干旱风沙草原区 植物防护体系 土壤理化性质 查干淖尔盐湖
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三峡库区消落带植物群落及其功能性状对水淹强度的响应 被引量:1
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作者 程莅登 袁兴中 +2 位作者 孙阔 唐婷 袁嘉 《生态学报》 CAS CSCD 北大核心 2024年第11期4795-4807,共13页
植物功能性状能表征其对资源的利用能力和对外界环境的响应,而水淹强度的不同使得三峡库区消落带不同高程的生境存在较大差异,因此开展不同水淹梯度下消落带植物群落生态策略及功能性状差异的研究,对全面理解植物对消落带不同生境的适... 植物功能性状能表征其对资源的利用能力和对外界环境的响应,而水淹强度的不同使得三峡库区消落带不同高程的生境存在较大差异,因此开展不同水淹梯度下消落带植物群落生态策略及功能性状差异的研究,对全面理解植物对消落带不同生境的适应机理具有重要意义。研究选取受三峡水库水位变化影响的澎溪河流域,沿高程梯度对不同水淹强度下的植物群落及其功能性状指标进行分析。结果表明:(1)消落带植物群落处于演替的初级阶段,不同水淹梯度下的植物群落存在显著分化;(2)环境胁迫是决定消落带植物生态策略的主要因素,总体呈现较为集中的耐压策略,随着高程升高有逐渐向杂草策略转移的趋势;(3)随着高程升高,植物的高度、主茎干物质量、比根长及叶组织密度都有增大的趋势,比叶面积则相反。(4)各功能性状之间存在显著相关性,并通过形成不同的性状组合以适应不同强度水淹干扰的生境。消落带下部更倾向于投资于叶片使植物在出露期能快速获取资源和完成生活史,而消落带上部则更倾向于投资防御组织及根系以抵御干旱,研究结果可为消落带生物多样性保护及其生态系统修复提供理论依据。 展开更多
关键词 消落带 水淹强度 植物群落 功能性状 竞争-耐压-杂草生态策略
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植物种类对野芷湖湖岸带土壤反硝化作用的影响
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作者 雷芊芊 张翎 +4 位作者 胡荣桂 王砚 赵劲松 林杉 姜炎彬 《生态学报》 CAS CSCD 北大核心 2024年第3期1116-1129,共14页
反硝化作用是湖岸带有效去除氮素的关键氮循环过程,受到植物、土壤理化性质及微生物等因素的影响。为探究湖岸带不同植物对土壤反硝化作用的影响,通过调查测定野芷湖湖岸带9种常见植物的根际与非根际土壤的反硝化功能基因丰度和反硝化潜... 反硝化作用是湖岸带有效去除氮素的关键氮循环过程,受到植物、土壤理化性质及微生物等因素的影响。为探究湖岸带不同植物对土壤反硝化作用的影响,通过调查测定野芷湖湖岸带9种常见植物的根际与非根际土壤的反硝化功能基因丰度和反硝化潜势,分析其与土壤理化性质的关系,阐明植物种类影响反硝化作用的机制。研究结果表明:(1)种植植物会改变湖岸带土壤的理化指标,植物根际土的硝态氮(NN)、铵态氮(AN)、总碳(TC)、总氮(TN)和可溶性有机碳(DOC)含量等显著高于非根际土,其中柳树、黄素馨、喜旱莲子草根际土的TC、DOC、TN、NN显著高于其他物种,桂树的根际和非根际土的pH均显著低于其他物种;(2)植物根际土的微生物反硝化功能基因(narG、napA、nirS、nirK和nosZ)丰度显著高于非根际土,其中柳树、黄素馨、喜旱莲子草根际土的基因丰度显著高于其他物种,pH、TN、NN和DOC等对反硝化功能基因丰度影响较大;(3)根际土的反硝化潜势显著高于非根际土,其中柳树、桂树、黄素馨根际土的反硝化潜势显著高于其他物种,黄素馨非根际土的反硝化潜势也较高,pH、DOC、TN以及napA、nirS、norB基因丰度等对土壤的反硝化潜势具有显著影响。本研究说明植物根际微环境更有利于反硝化微生物的生长与繁殖,湖岸带种植植物时可考虑不同的常绿和落叶乔木、灌木、草本植物的合理配置来提高湖岸带的氮素截留能力,以减少由过量氮素进入水生生态系统导致的面源污染。 展开更多
关键词 植物 反硝化潜势 湖岸带 反硝化功能基因 土壤理化性质
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水库消落带植物多样性空间格局预测模型及环境解释--基于XGBoost-SHAP模型框架
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作者 刘瑞雪 李佳轩 李云 《生态学报》 CAS CSCD 北大核心 2024年第21期9652-9669,共18页
生物多样性的监测与预测对实现生物多样性保护及其可持续管理至关重要。传统方法通过实地调查来构建环境与生物多样性之间的多变量关系模型。空间大数据技术及机器和深度学习算法的发展为探索环境-生物多样性关系和预测生物多样性空间... 生物多样性的监测与预测对实现生物多样性保护及其可持续管理至关重要。传统方法通过实地调查来构建环境与生物多样性之间的多变量关系模型。空间大数据技术及机器和深度学习算法的发展为探索环境-生物多样性关系和预测生物多样性空间格局提供了新的视角和方法。构建了一种基于XGBoost算法的预测模型,融合实地调查的植物多样性数据和来自多源数据库的环境变量数据,分别构建了气候、地形、土壤、水文和人类活动5类共34个环境变量与植物群落物种丰富度、物种多样性和谱系多样性的关系模型,对丹江口水库消落带的植物多样性空间格局进行预测,同时结合SHAP框架确定关键环境因素;并进一步预测2050年水库消落带的植物多样性空间格局。研究表明,XGBoost算法在预测水库消落带植物多样性方面表现较好,3个多样性指标中谱系多样性的预测模型展现了最优的预测能力,而物种多样性预测模型的预测能力相对较低。结合SHAP分析发现年平均水淹时长、人类足迹与最冷季平均气温是影响消落带植物群落物种丰富度、物种多样性和谱系多样性的关键环境因素,其中年平均水淹时长的影响最为显著,随着年平均水淹时长增加,物种丰富度、物种多样性和谱系多样性降低。本研究构建的可解释预测模型可有效揭示消落带的植物多样性空间格局,为消落带生物多样性的保护和可持续管理提供科学依据,为生物多样性的监测和管理提供了新方法,对评估全球变化对生态系统的影响并促进生物多样性保护有重要意义。 展开更多
关键词 植物多样性 空间格局 预测模型 机器学习 消落带
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