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1.
针对四川盆地丘陵区农、林业生产特点和坡地农林复合系统特征,运用层次分析法(AHP),从结构、功能,效益方面设置评价指标,分别对系统中的6种林带类型和10种农作物复种方式进行综合评价,结果提出了3种较好的林带类型(即桤、柏混交和栎,柏混交-灌-草结构的林分以及桤木-草结构的林分)和4种较好的农作物复种方式(即小麦-花生、小麦/西瓜/蔬菜,蚕豆/玉米/红薯和蚕豆/西瓜/红薯等);为该区坡地农林复合系统  相似文献   

2.
根据四川盆地浅丘区农林复合系统特点,从理论上分析了该系统内天空散射辐射令布特征。提出了在林带和地形(坡度变化)的双重影响下的林带间平均相对辐照成分布特征,为农林复合系统的设计提供了依据;除林带本身产生“光胁地”外,地形变化即坡度的增加,叶“光胁地”效应有增强作用,对其范围有扩大作用。  相似文献   

3.
针对四川盆地长江防护林体系建成后区内农林复合特征,提出了农田林网型、坡地林带型、山地林药型、林农间作型和庭园复合型计5个类型30个农林复合模式的分类系统,运用动态经济分析方法优选出了适于四川盆地低山区和丘陵区生产发展的10个优良农林复合模式。  相似文献   

4.
坡地防护林带小气候因子与作物产量的关系   总被引:3,自引:0,他引:3  
本文着重测定了坡地防护林带间农地小气候因子与作物产量。结果表明,坡地防护林带对作物生长环境有明显影响,关联分析显示影响小麦产量的主导因子为光照强度。据此,文中提出了改善林带间农地光照条件的系列措施,便于农林业生产中应用。  相似文献   

5.
本文针对1997 年度四川盆北山丘区遭遇的严重旱情,探讨了阆中市岳家沟流域农林复合系统内的水分亏缺及其与农经作物生物生产力的关系,分析了不同林带距离对林带+ 水稻复合模式作物产量的影响,结果表明:土壤有效持水量和土壤相对含水量(RW )是土壤抗旱性能的重要指标,土壤一定的肥效性有利于土壤抗旱性能的提高;在连续干旱40天后,系统内各农林复合模式土壤水分亏缺极为严重,并对花椒成活和生长、大春作物产量及产品的经济性状构成了严重的影响,其中花椒成活率为60.7% ~75.0% ,各大春作物相对减产幅度为玉米30.9% ,花生46.0% ,水稻28.9% ~62.2% ,棉花23.6% ~59.3% ,表现出整个系统综合抗旱能力较差;在水分亏缺之下,不同林带距离水稻生物生产力差异显著,并表现出林带对农作物的光胁地在一定范围内并不表现为负效益而相对具有增产的作用。  相似文献   

6.
文章从农林复合系统的结构选择、对生态环境的影响和系统内部作物与环境相互作用三个方面对农林复合系统研究现状进行分析,并指出要在把握农林系统整体性的基础上,采用多种方式开展复合结构模式研究,重点开展农林复合系统种间相互作用机理的研究。  相似文献   

7.
蜘蛛是华北农区的主要天敌种群之一,本文研究了农田蜘蛛种群结构及优势种在林带-田埂-农田环境的分布动态。结果表明:(1)研究地区游猎型蜘蛛的优势种为中华狼蛛(Lycosa sinensis Schenkel)和中华平腹蛛(Gnaphosa sinensis Simon);(2)林带和田埂在农作物栽种前和成熟后是蜘蛛栖息和获取食物的主要场所,是农林复合系统中蜘蛛种群的重要种库;(3)耕作活动对蜘蛛种群有较强的负面影响,林带环境具有维持蜘蛛种群稳定性的作用;(4)蜘蛛密度与距林带距离呈负相关性,且在距林带一定范围内密度变化极其显著(P=0.001,α=0.05),表现出明显的林带效应。  相似文献   

8.
农林草复合种植系统对生态环境修复以及农林业的可持续发展具有重要意义,农林间作是现代农林复合系统研究的核心内容之一,林草复合系统属于农林复合系统的一大类。该文在明确农林草复合种植系统的概念与内涵的基础上,重点分析了农林草复合生态系统在阻控坡地水土流失方面的研究成果及对土壤理化性质的影响,提出应把农林草复合种植系统做为一个多层次的整体,综合考量其各层次的耦合机制及防蚀效应。  相似文献   

9.
本文对坡地林农复合系统水文效应进行的研究结果表明,复合系统中林地土壤非毛管孔隙对降水的有效调蓄能力比荒草坡强;全年除了3月,5月外,复合系统农地土壤含水量均比对应的纯农地略高;采用横坡聚土垄作或土石护坎工程可有效地减少复合系统农地水土养分的流失量。  相似文献   

10.
农林复合经营系统研究现状   总被引:2,自引:0,他引:2  
综述了当代农林复合经营系统的概念、内涵、产生的背景以及发展历史。分析了国内外农林复合经营系统在分类、组分间的相互作用、模式建立及优化、系统功能和作用、系统的整体效益评价以及技术推广等各方面的研究现状,并对当代农林复合经营系统的研究前景进行展望。  相似文献   

11.
农林复合系统结构优化的研究   总被引:8,自引:0,他引:8       下载免费PDF全文
对河北饶阳试区的土地利用方案和10种类型的果—农间作体系的合理配置进行了研究,通过计算机数据处理,从中筛选出优化的结构模式和土地利用方案。结果表明:①农林复合生态系统中土地优化利用方案的规划应该考虑市场的价值变动,还应该考虑到在林木的生长前期投入与经济效益的问题。②发展的农、林产品有梨树、油菜和棉花。③雪花梨和鸭梨为主的模式,其最佳栽植模式是株行距为3m×5m,两行或三行为一带,带距为30m。④果—农模式体系中农作物品种的配置以小麦—蔬菜组合为最好,产投比为2.7∶1;其次为油菜—蔬菜组合;粮食类较好组合有小麦—薯类、小麦—玉米、小麦—谷子、小麦—黄豆、油菜—玉米等。  相似文献   

12.
王棣  李勇  刘劲  张云龙  龚怀勋 《林业科学》1999,35(6):115-118
目前发展山地经济林普遍存在水、肥补给这一当前经济林建设中的一个突出问题1),防止大面积山地经济林地力衰退,实现持续、高产、高效栽植也要解决这个重要问题。我们针对太行山石灰岩区的自然地质条件,提出了隔坡复式梯田整地山地经济林发展新模式(王棣等,1996),并开展了较为系统的研究。1 研究地区自然概况和试验地条件1.1 研究地区自然概况 本研究是在太行山石灰岩区的平顺县进行的。位于东经113°11′~113°43′7″,北纬35°57′~36°27′4″之间,海拔1000~1400m,属暖温带大陆季…  相似文献   

13.
This paper examines how agroforestry-based farming systems evolved in the Dhanusha district of Nepal following the conversion of forest into agriculture during the early 1950s. Some data are from two focus group discussions with agroforestry farmers and one meeting with agroforestry experts. The farmers?? discussion traced the development of farming practices from 1950 to 2010 to identify the drivers of land use change. The experts?? discussion resulted in a scale to differentiate the prevailing farming systems in the study area considering five key components of agroforestry: agricultural crops, livestock, forest tree crops, fruit tree crops and vegetable crops. Data related to the system components were collected from the randomly selected households. The study reveals that land use had generally changed from very simple agriculture to agroforestry, triggered by infrastructure development, technological innovations, institutional support (subsidies and buy-back guarantees) and extension programs. A range of farming systems with varying degrees of integration was evident in the study area: simple agriculture; less integrated agroforestry; semi-integrated agroforestry and highly integrated agroforestry. The three types of agroforestry systems, which are the focus of this study, varied significantly in terms of farm size, cropping intensity, use of farm inputs, tree species diversity, tree density, home to forest distance and agricultural labour force.  相似文献   

14.
采用区域特征分析的方法开展森林城市建设规划,在对湖北省咸宁市的生态格局、林业产业格局和森林文化特色等区域特征进行分析的基础上,确立了咸宁市森林城市建设"一心、五翼、二廊、三带、三区、多点"的总体布局,并构建森林生态体系、森林产业体系、生态文化体系和支撑体系四大工程框架。实践证明,这种方法可以使规划更加贴近实际,具有更强的可操作性。  相似文献   

15.
An experiment in the Blue Mountains of Jamaica investigated the consequences of three land-use treatments applied following forest clearance on soil fertility and resulting crop growth over a five year period. The treatments were: maintained weed-free without cultivation (bare); cultivated with herbaceous crops (agriculture); and cultivated with herbaceous crops and intercropped with Calliandra calothyrsus contour hedges (agroforestry) and compared with an uncleared secondary forest control (forest). Nitrogen mineralisation rates declined over time since forest clearance in the cleared treatments, but not in the forest. In the second and third years after clearance nitrogen mineralisation was higher under the hedgerows than all other treatments. However, by the fifth year this had reduced to net immobilization (both under and between hedgerows). Under controlled shade-house conditions bioassay plant growth was similar in soil from agricultural plots and from forest plots. In all the soils bioassay plant growth showed a slight (not significant) positive response to P addition. However, it did show a large positive response to N addition in all soils: most for agriculture soils, least for forest soils and intermediate for agroforestry. Crop plants growing in the agroforestry plots had significantly higher growth than those in the agriculture plots. This was sufficient to lead to grain yield per hectare being only 5% lower in agroforestry plots despite there being c. 20% fewer maize plants per hectare than in the agriculture plots. However, the results suggest that there was no clear positive effect of C. calothyrsus on soil fertility five years after establishment.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

16.
Research was conducted in Alutilla Valley in eastern Bangladesh to identify the nature of existing agroforestry systems and to identify potential agroforestry models that could ameliorate currently degrading forest resources Data were collected through farmer participatory research and a structured quarterly survey in two villages. Qualitative and supplementary quantitative analysis methods were used to assess the financial potential of agroforestry systems. Various patterns of agroforestry exist in the study site, but all have two common principles, namely ‘integration with agriculture’ and ‘multi-functionality’. Two agroforestry models suitable for adoption by farmers have been identified. Multi-strata agroforestry, based on a fruit and timber tree canopy with vegetables and tuber species in the understorey, can be practiced in the shifting cultivation fields near settlements. Fruit and timber tree-based conservation agroforestry is well suited to manage large-scale biologically depleted landscapes. Both systems yield early financial returns, facilitating the change from shifting cultivation to multi-strata agroforestry or fruit and tree-based conservation agroforestry.  相似文献   

17.
沙地樟子松人工林混农经营的生态经济效益   总被引:1,自引:0,他引:1  
在沙区樟子松人工林中开展混农经营研究,结果表明:混农经营改善了林地的水分养分条件,增强了林木抗病能力,并且种植带内风蚀程度很轻;混农经营促进了林木生长,当种植带宽度为7 m时,花生、黑豆产量分别达到农田地产量的80%、60%,实现了林地长短期经济效益的结合。在樟子松人工林中开展混农经营兼顾了林分的生态和经济效益。  相似文献   

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