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Assessment of tree diversity and above-ground biomass in coffee agroforest dominated tropical landscape of India's Central Western Ghats
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作者 Guddappa M.Devagiri Anil Kumar Khaple +3 位作者 Hosuru B.Anithraj Cheppudira G.Kushalappa Amaresh Kumar Krishnappa Shashi Bhushan Mishra 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第3期1005-1015,共11页
The purpose of this study was to quantify the changes in tree diversity and above-ground biomass associated with six land-use types in Kodagu district of India's Western Ghats. We collected data on species richnes... The purpose of this study was to quantify the changes in tree diversity and above-ground biomass associated with six land-use types in Kodagu district of India's Western Ghats. We collected data on species richness,composition and above-ground biomass(AGB) of trees,shrubs and herbs from 96 sample plots of 0.1 ha. Totals of83 species from 26 families were recorded across the landuses. Tree species richness, diversity and composition were significantly higher in evergreen forest(EGF) than in other land-uses. Similarly, stem density and basal area were greater in EGF compared to other land-uses. Detrended correspondence analysis(DCA) yielded three distinct groups along the land-use intensities and rainfall gradient on the first and second axes, respectively. The first DCA axis accounted for 45% and second axis for 35% of the total variation in species composition. Together the first two axes accounted for over 2/3 of the variation in species composition across land-use types. Across the land-uses,AGB ranged from 58.6 Mg ha-1 in rubber plantation to327.3 Mg ha-1 in evergreen forest. Our results showed that species diversity and AGB were negatively impacted bythe land-use changes. We found that coffee agroforests resembled natural forest and mixed species plantation in terms of tree diversity and biomass production, suggesting that traditional coffee farms can help to protect tree species, sustain smallholder production and offer opportunities for conservation of biodiversity and climate change mitigation. 展开更多
关键词 WESTERN Ghats COFFEE agroforest Land-use changes Diversity Above-ground biomass Carbon
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Diversity of plant species in arecanut agroforests of south Meghalaya,north-east India
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作者 H.Tynsong B.K.Tiwari 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第3期281-286,396,共7页
In south Meghalaya, farmers maintain a variety of economically important plant species in arecanut agroforestry systems. We investigated plant species composition of arecanut agroforests of south Meghalaya and encount... In south Meghalaya, farmers maintain a variety of economically important plant species in arecanut agroforestry systems. We investigated plant species composition of arecanut agroforests of south Meghalaya and encountered 160 plants, which included 83 tree species, 22 shrub species, 41 herb species and 14 climber species. The study reveals that arecanut agroforests provide cash income, medicine, timber, fuelwood and edibles for household consumption as well as for sale. We conclude that these agroforestry systems serve as home for many economically important plant species, harbour rich biodiversity and mimic the natural forests both in structural composition as well as ecological and economic functions. 展开更多
关键词 agroforests ARECANUT DIVERSITY South Meghalaya War Khasi
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Spatial Organisation Influences Citrus <i>Pseudocercospora</i>Leaf and Fruit Spot Disease Severity in Cocoa-Based Agroforestry Systems
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作者 Eunice Golda Danièle Ndo Etienne Akoutou Mvondo +5 位作者 Zachée Ambang Bella Manga Christian Cilas Lucien Bidzanga Nomo Cynthia Gidoin Marie-Ange Ngo Bieng 《American Journal of Plant Sciences》 2019年第1期221-235,共15页
An investigation to assess the spatial structure and severity of Pseudocercospora leaf and fruit spot disease (PLFSD) on citrus trees in cocoa-based agroforests was carried out in three contrasting ecological zones in... An investigation to assess the spatial structure and severity of Pseudocercospora leaf and fruit spot disease (PLFSD) on citrus trees in cocoa-based agroforests was carried out in three contrasting ecological zones in southern Cameroon, viz: 1) the humid forest zone, 2) the degraded forest zone, and 3) the forest-savannah transition zone. Two main parameters were investigated viz: 1) the spatial structure of cocoa based agroforests, and 2) the disease severity. In total, the spatial structure of 19 cocoa-based agroforests was analysed using the Ripley K(r) function, meanwhile the collection of epidemiological data that consisted of noting the presence of PLFSD spots on leaves and fruits on 438 citrus trees was used to characterise the severity of the disease. Results showed that, the spatial structure of citrus trees in these agroforests investigated were regular in seven plots, random in nine, and aggregated in three. Aggregated plots presented a significantly higher mean of disease severity on leaves and fruits (28.55 and 30.37 respectively), as compared to randomised (20.91 and 16.32 respectively) and regular plots (16.28 and 14.97 respectively), at P-value < 0.05. These results suggest that the spatial structure of citrus trees in the cocoa-based agroforests studied influences the severity of PFLSD. Proper integrated control measures can therefore be initiated, leading to a considerable reduction of the use of manufactured inputs, and thereby, the cost of production of citrus fruits. 展开更多
关键词 Aggregated SPATIAL Structure Ripley Function Agroecological Management of Disease PSEUDOCERCOSPORA angolensis Cocoa-Based agroforests CITRUS
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A Study of the Relationship between Low-level Jet and inversion Layer over an Agroforest Ecosystem in East China Plain
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作者 钟中 王汉杰 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第2期299-310,共12页
The relationship between the super–low–level jet (LLJ) and inversion layer over an agroforest ecosystem on the Huang–Huai–Hai plain in the eastern China is studied by means of a time–independent K–closure model.... The relationship between the super–low–level jet (LLJ) and inversion layer over an agroforest ecosystem on the Huang–Huai–Hai plain in the eastern China is studied by means of a time–independent K–closure model. It is found that the intensified inversion near the surface of a luxuriantly growing agroforest ecosystem leads to the formation and development of the LLJ, the more intense the inversion, the stronger is the LLJ. The critical value of inversion intensity index for the LLJ formation is 0.75°C/ 100 m, which relates to the necessary geostraphic wind velocity of 6.0 to 10 m / s at the top level of the model. The numerical calculations show that the roughness length of the underlying surface has considerable effects on the LLJ structure. Key words Low?level jet - Temperature inversion - Agroforest ecosystem The project was supported by the National Natural Science Foundation of China (NSFC) (49975016). 展开更多
关键词 Low-level jet Temperature inversion agroforest ecosystem
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A simulation study on CO_2 assimilation and crop growth in agroforest ecosystems in the East China Plain
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《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第4期81-89,共9页
AsimulationstudyonCO2asimilationandcropgrowthinagroforestecosystemsintheEastChinaPlainZhouLin,WangHanjieEcoE... AsimulationstudyonCO2asimilationandcropgrowthinagroforestecosystemsintheEastChinaPlainZhouLin,WangHanjieEcoEnvironmentalRese... 展开更多
关键词 A simulation study on CO2 assimilation and crop growth in agroforest ecosystems in the East China Plain CO
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Typology and Agroecology of Agroecosystems in Vegetation Dynamics in the Ecotones of the Mbam and Inoubou
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作者 Alex Bruno Dong Etchike Lucie Félicité Temgoua +3 位作者 Bertine Tiokeng Marie Caroline Momo Solefack Martin Benoit Ngassoum Pierre Marie Mapongmetsem 《Open Journal of Forestry》 2024年第1期42-66,共25页
Agroforestry systems strongly characterize the Cameroonian agrarian landscape. Agroforests are among those structuring the ecotones of Mbam and Inoubou in the Central Cameroon region. Numerous works on agroecosystems ... Agroforestry systems strongly characterize the Cameroonian agrarian landscape. Agroforests are among those structuring the ecotones of Mbam and Inoubou in the Central Cameroon region. Numerous works on agroecosystems of Central and South Cameroon, few have come out contribution of the structure of these traditional systems in the dynamics of the vegetation of these forest-savannah ecotones. The present contribution has the overall objective of demonstrating the structural efficiency of agroforests the dynamics of ecotone vegetation, but also in the conservation of biodiversity. To do this, a participatory analysis was carried out with 56 farmers distributed in the five villages of Makénéné. Botanical inventories supplemented socio-economic household surveys. The data collected was subjected to various analyzes (univariate test, analysis of variance, multivariate test, PCA, CAH). The results reveal that 55.2% of agroforests are less than 15 years old and those with an area greater than 1500 m<sup>2</sup> predominate (33%). They are mainly young with generally small surface areas. The horizontal structure reveals that the largest diameter classes are those of [20 - 30 cm[ and [10 - 20 cm[ with a very low rate of basal area. Agroforests with trees over 10 m high are dominant in five villages of Makénéné. Two types of structural profiles characterize the agroforestry flora of the area, namely intensive pluristratified home gardens on savannah and intensive pluristratified agroforests under forest-savannah transition vegetation. Principal Component Analysis (PCA) and Ascending Hierarchical Clustering (HAC) show three Agroforest Clusters each. The PCA distribution reveals that woody biomass (Y) is strongly correlated with tree diameter (DBH) and significantly with height (Cluster 2). The age (AAG) (Cluster 1) of these agroforests, on the other hand, remains independent of the density (DST) of these trees (Cluster 3). The agroforests in the Nyokon, Carrière and Mocksud villages are the most effective in terms of conserving woody diversity while the agroforests of the Kinding ndé and Nyokon villages are more efficient in the reforestation processes. These results could be considered as effective and quantifiable tools for the certification of numerous cash crops such as cocoa and coffee, which will make it possible to valorize this local knowledge in terms of scientific and in the development of various programs and writing of technical notes. 展开更多
关键词 agroforests AGROECOSYSTEM Center Cameroon Dynamics AGROECOLOGY TYPOLOGY
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岷江源头区农林复合景观变化对土壤侵蚀强度的影响 被引量:6
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作者 刘洋 李春阳 龙翼 《农业工程学报》 EI CAS CSCD 北大核心 2009年第7期232-236,共5页
研究植被景观对土壤侵蚀的影响对旨在控制水土流失的流域生态恢复工作来说十分重要。该文利用遥感和GIS技术对岷江源头区的农林复合景观和土壤侵蚀强度的变化进行分析,并从景观角度分析了该区域农林复合景观变化对土壤侵蚀强度变化的影... 研究植被景观对土壤侵蚀的影响对旨在控制水土流失的流域生态恢复工作来说十分重要。该文利用遥感和GIS技术对岷江源头区的农林复合景观和土壤侵蚀强度的变化进行分析,并从景观角度分析了该区域农林复合景观变化对土壤侵蚀强度变化的影响。从不同景观类型对土壤侵蚀强度的控制能力大小看:针叶林>落叶阔叶林>针阔混交林>灌丛>草地>农用地。对于除农用地以外的其他植被景观类型来说,增加其平均斑块面积和形状的复杂性会在一定程度上减少土壤侵蚀强度。而对于农用地来说,斑块形状的简单化以及均匀镶嵌的分布形式则是减少土壤侵蚀强度的有效手段。 展开更多
关键词 土地利用 植被 土壤侵蚀强度 农林复合景观 岷江源头区
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紫胶玉米混农林模式对地表蚂蚁多样性及功能群的影响 被引量:9
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作者 卢志兴 李可力 +1 位作者 张念念 陈又清 《中国生态农业学报》 CAS CSCD 北大核心 2016年第1期81-89,共9页
为了揭示紫胶玉米混农林对地表蚂蚁群落多样性及功能群的影响,采用陷阱法调查了云南省绿春县紫胶林、紫胶玉米混农林和玉米旱地3种类型样地的地表蚂蚁物种组成、物种多样性、群落结构相似性、指示物种和功能群等。结果显示,紫胶玉米混... 为了揭示紫胶玉米混农林对地表蚂蚁群落多样性及功能群的影响,采用陷阱法调查了云南省绿春县紫胶林、紫胶玉米混农林和玉米旱地3种类型样地的地表蚂蚁物种组成、物种多样性、群落结构相似性、指示物种和功能群等。结果显示,紫胶玉米混农林模式具有较高的地表蚂蚁物种数和稀有物种数,与玉米旱地相比,紫胶玉米混农林的蚂蚁物种数增加41%,稀有物种数增加85%。紫胶玉米混农林与紫胶林具有更高的蚂蚁多样性,其物种丰富度和ACE估值均显著高于玉米旱地,而紫胶玉米混农林的多度显著高于紫胶林和玉米旱地。地表蚂蚁物种组合在3种类型样地中有差异,与紫胶林和紫胶玉米混农林相关联的物种与玉米旱地不同。3种样地的指示物种不同,玉米旱地的指示种为扁平虹臭蚁和伊大头蚁,紫胶玉米混农林为凹头臭蚁、西昌刺结蚁和中华小家蚁,紫胶林为费氏盘腹蚁、立毛举腹蚁、阿普特铺道蚁、贝卡盘腹蚁和西氏拟毛蚁。紫胶玉米混农林蚂蚁功能群组成比例介于玉米旱地和紫胶林之间,其中机会主义者(OPP)、从属弓背蚁族(SC)、隐蔽物种(C)及气候特化种(CS)的蚂蚁物种数、多度及比例明显高于玉米旱地。紫胶玉米混农林生境较为复杂,对地表蚂蚁多样性保护具有积极作用,是平衡环境保护和经济可持续发展的较好模式。 展开更多
关键词 土地利用 紫胶玉米混农林模式 地表蚂蚁 群落组成 生物多样性 指示物种 功能群
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黄土高原沟壑区混农林的结构及其防护效益研究 被引量:20
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作者 王佑民 王忠林 《水土保持学报》 CSCD 北大核心 1992年第4期54-59,共6页
黄土高原沟壑区混农林类型可划分为星散林、带状林、间作林、片状林、村庄林、复合林6种。其结构特征可主要由林木覆盖度、林木分布度来表述。当林木覆盖度达到10%~20%,林木分布度为0.3~0.5时,防风效益可达20%以上,增产效益可超过... 黄土高原沟壑区混农林类型可划分为星散林、带状林、间作林、片状林、村庄林、复合林6种。其结构特征可主要由林木覆盖度、林木分布度来表述。当林木覆盖度达到10%~20%,林木分布度为0.3~0.5时,防风效益可达20%以上,增产效益可超过5%。上述覆盖度及分布度指标可作为确定平原绿化标准的参考。 展开更多
关键词 防护效益 黄土高原 林粮间作
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黄土残塬沟壑区混农林系统土壤养分研究初报 被引量:7
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作者 刘荣 朱清科 《西北林学院学报》 CSCD 1993年第2期46-51,共6页
分析了1991~1992年淳化县泥河沟流域塬面的道路防护型和农桐间作型混农林系统土壤养分的试验资料,结果表明,虽然混农林系统土壤养分垂直分布规律与一般农田一样,但变化梯度大。而林木的存在对农田土壤养分的水平分布产生了明显的影响。
关键词 黄土高原 土壤有效养分 林粮间作
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农林复合系统生态边界层特性的三维数值模拟 被引量:1
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作者 李训强 王汉杰 《应用气象学报》 CSCD 北大核心 2000年第1期71-79,共9页
该文介绍了一个包含地形起伏和地面植被效应的三维生态边界层模式.与经典的边界层气象学模式相比,模式更加细腻地考虑了与农林作物生长过程有关的热力、动力学作用,诸如植被冠层引起的辐射减弱,叶面气孔引起的水汽蒸腾,以及不同土... 该文介绍了一个包含地形起伏和地面植被效应的三维生态边界层模式.与经典的边界层气象学模式相比,模式更加细腻地考虑了与农林作物生长过程有关的热力、动力学作用,诸如植被冠层引起的辐射减弱,叶面气孔引起的水汽蒸腾,以及不同土壤质地引起的热量传输等.模式较成功地模拟了我国黄淮海平原中心区大面积农林复合生态系统的生态边界层结构及其热力、动力学特性.模式的输出结果与野外的低空探测实验作了比较.其一致性是令人满意的. 展开更多
关键词 农林复合生态系统 生态边界层 三维数值模拟
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渭北旱塬混农林综合体系小气候效应研究 被引量:2
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作者 王忠林 《西北林学院学报》 CSCD 1993年第2期52-57,共6页
本文通过对渭北地区旱塬混农林综合体系小气候效应的观测与分析,结果表明:混农林综合体系能够改善农田小气候,小气候特征与林木覆盖度、林木冠体及林木分布度关系密切,与林木株数、林木平均高度关系不密切。
关键词 干旱区 小气候 渭北地区 林粮间作
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Laboratory for New Urban Biotopes
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《Journal of Civil Engineering and Architecture》 2020年第2期80-91,共12页
The significance of urban green space in the metropolis gains weight if ecological value is linked to daily use in the urban living environment in a proper manner.A different layout of the urban domain is needed for a... The significance of urban green space in the metropolis gains weight if ecological value is linked to daily use in the urban living environment in a proper manner.A different layout of the urban domain is needed for a contribution to climate adaptation and biodiversity increase,and it is relevant to examine how plants can develop more according to the principles of succession of natural vegetation.Creating a 1:1 laboratory in Merwede,the Netherlands,provides a test case for introducing the urban biotope at various locations.Greenery in the city may be different than a natural ecosystem,but it can meet qualities that contribute to biodiversity,improvement of the urban air quality,reduce heat stress,seasonal effects and food production in the city. 展开更多
关键词 AGRICULTURE agroforest BIODIVERSITY foodscapes LANDSCAPE permaculture PLANTING urbanism.
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面向21世纪的中国农业工程议程探索
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作者 曾德超 《山东工程学院学报》 CAS 2000年第1期1-4,共4页
本文回顾了我国 2000~ 2030年瓶颈时期食物安全和农业水资源安全问题的各种预测;讨论了农业科技的对策;提出了实现中国农业现代化也及贯彻国家生态环境建设规划(2000~2050)所需优先发展的农业工程科技领域、建议... 本文回顾了我国 2000~ 2030年瓶颈时期食物安全和农业水资源安全问题的各种预测;讨论了农业科技的对策;提出了实现中国农业现代化也及贯彻国家生态环境建设规划(2000~2050)所需优先发展的农业工程科技领域、建议在这些优先领域,大力开展结合各个地区特定条件的国际合作研究和合资经营。开发、推广与实施先进适用型技术、指出这是获得未来潜在市场最高份额以及快速发展的途径。 展开更多
关键词 可持续农业 中国 农业工程 21世纪 农业水资源
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不同果农复合模式土壤酶活性特征研究 被引量:1
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作者 韩冰冰 马玉华 +2 位作者 傅松玲 肖正东 王陆军 《广东农业科学》 CAS CSCD 北大核心 2014年第1期52-55,60,共5页
选取皖北地区5种典型的果农复合模式,即苹果+银杏苗(P*Y)、苹果+石榴苗(P*S)、苹果+桃苗(P*T)、苹果+白术(P*B)、苹果+辣根(P*L),以纯林模式为对照,对不同模式土壤酶活性的特征进行研究。结果表明,与纯林模式相比,不同果农复合模式土壤... 选取皖北地区5种典型的果农复合模式,即苹果+银杏苗(P*Y)、苹果+石榴苗(P*S)、苹果+桃苗(P*T)、苹果+白术(P*B)、苹果+辣根(P*L),以纯林模式为对照,对不同模式土壤酶活性的特征进行研究。结果表明,与纯林模式相比,不同果农复合模式土壤酶活性均有所提升,其中以P*Y、P*B两种模式效果最好,不同模式土壤酶活性具有明显的空间分布特征;土壤蔗糖酶、脲酶及蛋白酶活性均随土层深度的加深呈不断降低的趋势,过氧化氢酶活性则随土层深度的加深不断升高;土壤酶活性具有明显的季节特征,其中蔗糖酶、脲酶及蛋白酶均在夏季活性最高,过氧化氢酶活性最大值则出现在秋季。 展开更多
关键词 果农复合模式 土壤酶活性 季节特征 空间分布
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气候低适宜区域橡胶种植模式对蚂蚁多样性的影响 被引量:1
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作者 于潇雨 卢志兴 +2 位作者 李巧 燕迪 陈又清 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2019年第10期1472-1480,共9页
为了揭示中、低适宜区域橡胶种植地的生物多样性状况,及选择有益于保护生物多样性的种植模式,使用陷阱法于2015年9月和2016年8月调查了钝叶黄檀-玉米地(对照)、橡胶纯林(Ⅱ)、橡胶-茶树混农林(Ⅲ)、橡胶-咖啡混农林(Ⅳ)中地表层和树冠... 为了揭示中、低适宜区域橡胶种植地的生物多样性状况,及选择有益于保护生物多样性的种植模式,使用陷阱法于2015年9月和2016年8月调查了钝叶黄檀-玉米地(对照)、橡胶纯林(Ⅱ)、橡胶-茶树混农林(Ⅲ)、橡胶-咖啡混农林(Ⅳ)中地表层和树冠层蚂蚁物种多样性、群落结构差异及指示物种,以研究不同类型种植模式间蚂蚁群落间的差异。结果表明:4种类型样地中,地表层蚂蚁中多度、物种丰富度、ACE值均存在显著差异(P<0.05),大小排序为橡胶-茶树混农林>橡胶纯林>钝叶黄檀-玉米地>橡胶-咖啡混农林;树冠层蚂蚁群落多度存在显著差异(P<0.05),大小排序为橡胶纯林>橡胶-茶树混农林>橡胶-咖啡混农林>钝叶黄檀-玉米地,物种丰富度和ACE值不存在显著差异(P>0.05)。地表层和树冠层蚂蚁群落结构样地类型间均存在极显著差异(P<0.01),其中橡胶-茶树混农林的蚂蚁群落结构与其余样地存在较高的相似性。4种类型样地中均存在1种指示物种,钝叶黄檀-玉米地为棒刺大头蚁(Pheidole spathifera),橡胶林为黑头酸臭蚁(Tapinoma melanocephalum),橡胶-茶树混农林为环纹大齿猛蚁(Odontomachus circulus),橡胶-咖啡混农林为缅甸细长蚁(Tetraponera birmana)。从本研究来看,橡胶-茶树混农林是当地橡胶复合农林系统中既具经济效益,又能较好保护蚂蚁多样性的种植模式。 展开更多
关键词 气候低适宜区域 复合农林生态系统 橡胶林 蚂蚁 物种多样性 群落结构 指示物种
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Soil Erosion of Varions Farming Systems in SnbtropicalChina
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作者 ZHANG BIN, ZHANG TAOLIN and ZHAO QIGUO(Institute of Soil Science, Academza Sznzca, P.O. Boz 821, Nanjing 210008(China)) 《Pedosphere》 SCIE CAS CSCD 1994年第3期225-233,共9页
In order to optimise land use systems, to prevent erosion-induced degradation and to restore the degradedred soils in subtropical China, five cropping systems and four agroforestry systems were conducted in red soilsw... In order to optimise land use systems, to prevent erosion-induced degradation and to restore the degradedred soils in subtropical China, five cropping systems and four agroforestry systems were conducted in red soilswith a slope of 7° from 1993 to 1995. The results showed that erosion risk period occurred from April to June,and the annual runoff and the losses of soil and nutrients with sediment were alarming for two conventionalfarming systems, whereas they were negligible for the farming systems with ridge tillage. Enrichment ratiosof the lost soils from erosion were more than 1 .20 for all nutrients with much higher values for hydrolysable Nand organic matter. Compared with the control, the alley cropping systems also distinctly decreased runoffby 30% or 50%. However, the coverage of soil surface varied with alley cropping systems for the competitionof nutrients and soil water, which made a profound difference in runoff. The cropping systems of sweet potatointercropped with soybean, the alley cropping systems and the measures of mulching and ridge tillage werethe alternatives for red soil reclamation so as to prevent erosion-induced degradation. 展开更多
关键词 agroforest SYSTEM FARMING SYSTEM RED SOIL SOIL EROSION
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农林复合生态系统与低层大气间的通量研究 被引量:4
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作者 王汉杰 《应用生态学报》 CAS CSCD 1999年第5期534-538,共5页
根据近年在黄淮海平原大面积农林复合区的观测资料,采用简单的一维模型,讨论了此类复合系统与低层大气之间的热量、动量和水汽通量,比较了不同的结构林网形成的通量差异.结果表明,由于林冠层的摩擦作用,农林复合生态系统上空风速... 根据近年在黄淮海平原大面积农林复合区的观测资料,采用简单的一维模型,讨论了此类复合系统与低层大气之间的热量、动量和水汽通量,比较了不同的结构林网形成的通量差异.结果表明,由于林冠层的摩擦作用,农林复合生态系统上空风速随高度增大较快,动量输送总是向下的.在层结稳定的夜间,其数值较大,而在湍流比较活跃的正午前后,由于垂直风切变减弱,动量输送也相应减小.夜间农林作物冠层的辐射冷却加强,近地层逆温梯度增大,加之作物冠层内部因辐射冷却而造成水汽凝结,冠层上部水汽大于冠层内部,此时热通量和水汽通量均向下.这一现象在白天日出后开始逆转,日出后,地面升温加快,并逐渐形成超绝热梯度,致使热量通量向上.此时农林作物蒸腾加剧,冠层高度范围内水汽含量增大,造成水汽向上输送.文中还讨论了一维模式的缺点。 展开更多
关键词 农林复合区 生态系统 湍流通量 湍流混合长 大气
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科尔沁沙地林农复合经营综合效益评价
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作者 赵恺 岳永杰 +2 位作者 李旭 钟琪涵 文明 《林业调查规划》 2022年第5期146-151,共6页
对科尔沁沙地奈曼旗的6种林农复合经营模式的经济效益、生态效益和社会效益进行调查,并对其综合效益进行分析,筛选出不同治理模式下综合效益最大的种植模式。选取14个评价指标,构建沙地综合效益评价指标体系,运用集对分析法对6种治理模... 对科尔沁沙地奈曼旗的6种林农复合经营模式的经济效益、生态效益和社会效益进行调查,并对其综合效益进行分析,筛选出不同治理模式下综合效益最大的种植模式。选取14个评价指标,构建沙地综合效益评价指标体系,运用集对分析法对6种治理模式做出综合效益评价。结果表明,沙棘—苦参治理模式在经济效益方面纯收益最大,投资回收期最短;生态效益方面,化肥使用量最低,服务价值大;社会效益方面,人均纯收入最高,收益稳定,农户易理解接受;综合效益方面,通过计算相对贴近度,大小依次为沙棘—苦参模式(0.6979)>塞外红模式(0.5931)>沙果模式(0.4936)>元宝枫—万寿菊模式(0.4904)>火炬树—万寿菊模式(0.4251)>樟子松—万寿菊模式(0.3199)。 展开更多
关键词 科尔沁沙地 集对分析法 林农复合治理 综合效益评价
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河南省沙区林业可持续发展探讨 被引量:1
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作者 杨伟杰 郭际荣 +2 位作者 李大银 邢惠民 张明东 《中南林业调查规划》 2001年第1期29-32,共4页
通过对河南省沙区林业发展的现状及优势进行透彻地分析 。
关键词 沙区林业 农田林网 农林间作 河南 可持续发展
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