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1.
通过对辽西北地区4种典型农林复合模式对土壤改良的研究,结果显示,相对于对照原始荒地,农林复合模式具有降低土壤容重,增加土壤持水量、土壤孔隙度等作用,同时改善土壤肥力,增大土壤内氮、磷、钾含量,提升有机质含量。土壤质量综合评价显示,农林复合模式中大扁杏-花生-玉米对土壤的改良效果最好,大扁杏-麻黄草、樟子松-花生次之。在土层深度上,大扁杏-花生-玉米模式和大扁杏-麻黄草模式对0~20cm土层的土壤改良效果好于20~40cm;樟子松-花生模式结果与之相反。  相似文献   

2.
针对辽西北票地区枣农复合模式大面积的推广,枣树林地间农作物多年单一连作,不规范的整地方式致使土壤耕层贫瘠、底层紧实的现状,以辽西北票地区传统的整地方式秋季旋耕为对照,分别设置苗期垄沟深松30 cm、秋季翻耕25 cm、秋季深松30 cm三种不同的整地方式,分析不同整地方式对农林复合经营模式下玉米根系的影响。结果表明:秋季深松30 cm处理的玉米根条数要多于其他处理,而秋季深翻处理的玉米根表面积、总根长和根体积的表现要好于其他处理。  相似文献   

3.
在山西省黎城县,对以核桃、花椒、君迁子为林冠的林药、林粮、林经等16种农林复合栽培模式前3年的经济效益进行了统计,并以净现值为指标进行了经济效益评价。结果表明,以花椒为林冠的复合类型投入成本较核桃和君迁子的低,且收入较其它2种的高;林药复合类型总体经济效益高于林粮和林经复合类型;林药复合类型中花椒—板蓝根复合栽培模式的经济效益最好,林粮复合类型中花椒—谷子复合栽培模式的经济效益最好,林经复合类型中核桃—辣椒复合栽培模式的经济效益最好。  相似文献   

4.
以南果梨的根、茎、叶营养器官作为供体材料,花生、玉米、大豆种子作为受体材料,研究林农复合生态系统南果梨营养器官对3种农作物种子的他感作用效果。结果表明:南果梨根浸提液对玉米种子萌发抑制效应最强,且浓度越高,抑制作用越明显;根浸提液对花生种子、大豆种子的萌发影响效果不明显。南果梨茎浸提液在高浓度下对玉米、大豆种子萌发有抑制效应;而在低浓度下则对玉米、大豆种子萌发无影响。茎对花生种子的萌发几乎无影响。南果梨叶浸提液对玉米、大豆种子萌发均表现为抑制效应,且浓度越高,抑制作用越强。构建南果梨农林复合系统应首选南果梨—花生模式。  相似文献   

5.
对大山村经果林复合经营模式的种间生态关系、复合结构、时空序列、经济效益进行了调查研究。研究发现,林农的4种复合经营模式(柿—山芋;柿—油菜—花生;梨—玉米—小麦—辣椒;李—马铃薯—绿豆;柑桔—茶叶),均能较充分地利用光能,和有效改善林地生态环境,提高土壤养分含量。它们的复合层次明显,互相配合生长,季节安排合理,土地盈利率较高。  相似文献   

6.
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(0.697 9)>塞外红模式(0.593 1)>沙果模式(0.493 6)>元宝枫—万寿菊模式(0.490 4)>火炬树—万寿菊模式(0.425 1)>樟子松—万寿菊模式(0.319 9)。  相似文献   

7.
为减少坡耕地水土流失现状,提高种植经济收入,在秭归县九畹溪镇实施5种农林复合种植优化模式.以农作物作为对照,对这5种模式生长情况进行调查,同时对经济效益和生态效益进行评估.结果表明:①主要树种成活率在90%以上,保存率在85%以上,保存面积达100%;②从经济效益上来看,农林复合种植模式总收入远高于单纯农作物种植模式,进入盛产期后以核桃+茶叶埂模式收入最高,未进入盛产期时以香椿 药材+茶叶埂模式收入最高;③从生态效益来看,项目的实施每年平均可减少土壤流失532.61 t,年均径流量减少15 998.40 m3,全氮、全磷、有效钾年均流失量分别减少12.89,12.58,2.05 t.  相似文献   

8.
笔者选用林草、林药、林粮、林菜4种复合类型,通过采用覆盖保墒技术、界面根障技术,在平顺县阳高乡、黎城县李庄、榆次区什贴镇进行了农林复合模式栽培试验。从经济效益、生态效益、社会效益三方面分析了农林复合栽培模式在山西省部分地区林业生产中的作用,总结出该模式可以推广应用于山西省及周边立地条件相似的地区,应用前景广阔。  相似文献   

9.
通过连续3年试验监测,对江汉平原5种典型杨-农复合经营模式及效益进行了分析.结果表明:杨树幼林农林间作不仅能促进杨树生长,还可以获得明显经济效益.不同间作模式收益及影响杨树生长有差异,综合效益较好的模式有:杨树+西瓜+小麦、杨树+棉花+小麦和杨树+玉米+小麦.  相似文献   

10.
辽西地区在资源、技术、品种方面均有发展大扁杏的优势,结合实践,对当地发展大扁杏的可行性进行了简单的分析,并对常见的3种大扁杏深加工产品的加工技术要点进行了总结,以促进辽西地区大扁杏产业的发展.  相似文献   

11.
In the United States, agroforestry adoption has lagged behind progress in agroforestry systems research. This study sought to facilitate the communication of landowner land management objectives, values, knowledge and perceptions of the barriers and benefits to agroforestry through applied social marketing research methods and market segmentation analysis. A mail survey instrument was sent to 250 members of the Pennsylvania Association of Sustainable Agriculture (PASA) and 250 members of Woodland Owner Associations (WOA). Current management objectives and production strategies, agroforestry awareness, agroforestry interest, and perceptions regarding the benefits and obstacles to agroforestry adoption were gauged. Market segmentation was performed with a two-step cluster analysis to produce four agroforestry adoption potential models: Timber-Related Practices, Livestock-Related Practices, Specialty Crop-Related Practices, and Non-Adopters. The analyses showed that agroforestry practices could satisfy specific land management objectives within diverse populations. The method effectively identified similarities in agroforestry adoption scenarios. Market segmentation could be utilised as a social marketing tool to guide future policy development, scientific research, and the efficacy and relevance of future agroforestry research and outreach programs. The next step in program development should include the creation of a statewide multidisciplinary team comprised of university, non-profit association and landowner representation, to develop agroforestry applications relevant to each cluster and promote the practices through landowner-led on-farm demonstrations and workshops.  相似文献   

12.
Abstract

Soil erosion poses economic and environmental concerns in many tropical uplands. Agroforestry has been proposed as a sustainable land use that can mitigate soil erosion and promote the economic welfare of small farmers. To evaluate such claims, we must (a) develop a composite measure of effectiveness, such as a soil conservation index, and (b) define it in terms understood by the farmers who ultimately choose to adopt and implement agroforestry. We construct an empirical soil conservation index as a weighted average of farmer perceptions of four soil attributes and develop a statistical model of soil conservation benefits of agroforestry by using survey data from the Philippines. Accounting for self-selection bias, we evaluate the soil conservation benefits by testing the correlation between the index and the level of agroforestry adoption. Our estimated model shows that agroforestry can generate 15-20 percent soil conservation for the typical small farmer. We offer several methodological, practical, and policy insights. Because many farmers in developing countries face informational and capital constraints, our study suggests that public policies should support smallholder agroforestry, a type of “natural investment” in soil capital, to generate private and public benefits.  相似文献   

13.
Many expert-designed agroforestry projects enunciated in 1970s around the world, particularly in the developing countries, had uneven success due to inadequate adoption or abandonment after adoption. There are many empirical studies on factors affecting on-farm tree cultivation mainly where expert-designed agroforestry programmes were introduced but lacking in case of traditional agroforestry. Moreover, the concern to identify key factors influencing on-farm tree growing is gaining importance. The present study identifies key factors in on-farm tree growing based on investigation of traditional agroforestry using logistic regression approach. The study is based on household survey of 401 households located in Indian Western Himalaya. The factors affecting on-farm tree growing were grouped into: biophysical (included land use and infrastructural aspects) and social. Models predicting on-farm tree growing for each category were developed and key factors affecting on-farm tree growing in the respective category were identified. A composite model was also developed by combining biophysical and social factors. In the present study, farm size, agroclimatic zone, soil fertility, mobility and importance of tree for future generations respectively were the key factors which influenced tree growing. In contrast to many previous studies which considered either biophysical or social factors, the composite model in the present study reveals that both biophysical and social factors are simultaneously important in motivating the farmers to grow trees on their farms in traditional agroforestry. Moreover, the present study open vistas for using farmers’ experience and knowledge of adoption of agroforestry to stimulate on-farm tree growing. The wider implication of the study is that biophysical as well as social variables should be considered together in designing suitable agroforestry systems in various parts of the world.  相似文献   

14.
林农复合经营经济效益评价研究现状与展望   总被引:2,自引:0,他引:2  
文中梳理和概述了当前国内外林农复合经营经济效益评价的研究内容、评价指标和评价方法,认为现阶段对林农复合经营经济效益评价的研究存在以下问题:定量分析的理论研究较少,评价内容不够全面;评价结果不够精确,且缺乏广泛适用性;缺乏区域的最优化模式研究;缺乏对林农复合经营长期系统的跟踪研究等。在此基础上对林农复合经营的经济效益评价进行了展望:林农复合经营的经济效益评价应建立在可持续发展的基础之上,充分考虑经济、社会和生态因素,实现系统全面的评估;大力开发计算机模型等;加强多学科之间深层次、实质性的合作与交流。  相似文献   

15.
Agroforestry combines perennial woody elements (e.g. trees) with an agricultural understory (e.g. wheat, pasture) which can also potentially be used by a livestock component. In recent decades, modern agroforestry systems have been proposed at European level as land use alternatives for conventional agricultural systems. The potential range of benefits that modern agroforestry systems can provide includes farm product diversification (food and timber), soil and biodiversity conservation and carbon sequestration, both in woody biomass and the soil. Whilst typically these include benefits such as food and timber provision, potentially, there are benefits in the form of carbon sequestration, both in woody biomass and in the soil. Quantifying the effect of agroforestry systems on soil carbon is important because it is one means by which atmospheric carbon can be sequestered in order to reduce global warming. However, experimental systems that can combine the different alternative features of agroforestry systems are difficult to implement and long-term. For this reason, models are needed to explore these alternatives, in order to determine what benefits different combinations of trees and understory might provide in agroforestry systems. This paper describes the integration of the widely used soil carbon model RothC, a model simulating soil organic carbon turnover, into Yield-SAFE, a parameter sparse model to estimate aboveground biomass in agroforestry systems. The improvement of the Yield-SAFE model focused on the estimation of input plant material into soil (i.e. leaf fall and root mortality) while maintaining the original aspiration for a simple conceptualization of agroforestry modeling, but allowing to feed inputs to a soil carbon module based on RothC. Validation simulations show that the combined model gives predictions consistent with observed data for both SOC dynamics and tree leaf fall. Two case study systems are examined: a cork oak system in South Portugal and a poplar system in the UK, in current and future climate.  相似文献   

16.
辽西地区几种农林复合型水土保持林模式的研究   总被引:3,自引:0,他引:3  
辽西地区属半干旱丘陵区 ,由于地势起伏 ,雨量集中 ,土壤粘重 ,植被稀疏 ,森林覆盖率低 ,成为我省水土流失比较严重地区。水土流失的结果是导致表土破坏 ,底土裸露 ,土壤理化性质明显恶化 ,土地生产力下降 ,增加了植被恢复的难度。为迅速改变辽西地区贫瘠落后的面貌 ,恢复生态系统平衡。建国以来 ,这一地区开展了大面积人工造林工作 ,据统计资料表明 ,以油松纯林为主的水保林面积达 5 3万hm2 ,这些林分对改善区域生态环境 ,推动国民经济及社会各项事业的发展起到了重要作用。但以大面积纯林为主的油松水土保持林存在树种单一、层次简单、…  相似文献   

17.
ICRAF's main contributions to research related to soils have been a symposium, Soils Research in Agroforestry; a review of soil productivity aspects of agroforestry; a further review of the potential of agroforestry for soil conservation, covering both erosion control and maintenance of fertility; the construction of a computerized model to predict soil changes under agroforestry systems; and a handbook of practical methods of agroforestry for soil and water conservation in dryland Africa. In research on land evaluation, an environmental data base has been established, leading to a capacity to obtain information, for environmental conditions similar to those of a given site or area, on publications, multipurpose trees, crops, existing agroforestry systems and current experimental work. Land evaluation for agroforestry cannot be achieved merely by synthesis of methods from agriculture and forestry, but will require more data on the performance of agroforestry land utilization types. Recognition of problems of environmental degradation has become an integral part of planning for agroforestry research. By means of a partial synthesis between land evaluation and diagnosis and design, a procedure of site selection for agroforestry research and development has been established.Principal Scientist, ICRAF  相似文献   

18.
"山林复合经营项目"是韩国在1999年为了增加林业从业者的收入而正式实施的,主要包括短期收入、木材生产和复合山地管理3种类型。截至2005年,该项目在韩国国内的168个市(区)都得到了推广。文中主要介绍韩国山林农业系统,分析该系统存在的问题并探讨与之相应的解决方案,提出应在开发更可行的复合农林经营模式的基础上加大对林业从业者的培训和奖励力度并改善对复合农林业的支持制度。  相似文献   

19.
本文从黑龙江省西部平原缓丘农区的自然资源、气象状况及社会经济发展状况出发 ,对农林复合经营开发模式的类型及其效益进行探讨 ,提出了农林复合经营开发模式的基础、类型与结构组合设计原则 ,并讨论了农林复合经营开发模式的技术措施 ,为黑龙江省平原缓丘农区的资源合理利用 ,提供了理论依据  相似文献   

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