四川省云阳县桐粮间作类型及效益分析

本文简介了云阳县的自然条件和桐粮间作类型，着重分析了相粮间作的经济、生态及社会效益。最后，提出了进一步发展混农林业的建议。     

厚朴林和杜仲林间作玉米与大豆系统的土地利用率研究

研究土地利用率的核心意义,原于其能够缓解土地资源禀赋稀缺的现状;发展厚朴林和杜仲林间作玉米与大豆系统可以提高土地利用率,促进林农集约经营,有效保护生物多样性,促进中药材产业发展,增加农民的经济收益,推动社会主义新农村建设。     

Land tenure (in)security and crop-tree intercropping in rural Xinjiang,China

The relationship between land tenure security and long-term land-related investment is of great importance especially given the current flux in property rights systems of agricultural land in China. This paper empirically examines the role of land tenure security in farmers’ crop-tree intercropping decisions, and is based on a comparative analysis between contract land and wasteland holders in rural Xinjiang, China. Data from a survey, carried out in 2008 among 352 households in Awati County in Xinjiang, is used to estimate the factors that affect the adoption of crop-tree intercropping. The results indicate that, for those households that only have contract land, land tenure security positively affects their adoption of crop-tree intercropping. However, for those that hold both contract land and wasteland, land tenure security negatively impacts upon their adoption of crop-tree intercropping on wasteland, as the crop-tree intercropping on wasteland can increase the perceived tenure security of wasteland. The results also suggest that the comprehensive effect of labor organization on intercropping is moderate as a result of the presence of counteracting effects.     

Adaptation of Agroforestry Systems in South-Eastern Mexico through Integration of Farmer and Bioeconomic Evaluations

Agroforestry systems have been promoted as sustainable land-use systems for regions where shifting agriculture is the traditional predominant land-use. Although environmentally sustainable, agroforestry systems require investment to establish that may affect their economic sustainability. In the southern Yucatan Peninsula 47 agroforestry plots of two timber and 10 fruit tree species were established with 22 farmers in three communities covering two rainfall zones and five soil types. Some fruit trees had wide adaptability to different soil, rainfall and management conditions, e.g. Manilkara zapota; others were restricted to the best soil, rainfall management conditions, e.g. Persea americana. The Meliaceae timber trees responded little to rainfall and soil, but stem borer attack was markedly lower in less intensively managed systems. Level of system maintenance greatly affected costs, but also opportunities for intercropping and obtaining immediate income. All levels of managements had negative net present value (NPV) for the three-year establishment phase, but so does traditional maize production. Farmers preferred to inter-crop their agroforestry systems, but were often limited by site quality. Determining sustainable agroforestry options for farmers requires multiple decisions related to species adaptability to the site, farmer production objectives and farmer capacity to invest in different management strategies. One production technology did not fit all.     

Maize-legume intercropping in central Malawi: determinants of practice

In Malawi, population growth has reduced opportunities for farmers to expand and cultivate new land. The country's primary farming population is comprised of smallholders, many who cultivate monocultures of maize (Zea mays). To reduce negative outcomes from this practice, intercropping maize with legumes has been promoted. The sustainable intensification (SI) practice was once widely used, but has declined in recent decades. Little is known about the determinants of intercropping or its role in agricultural development. The objective of this study was to examine the drivers of intercropping among smallholders. We used multiple logistic regression analysis to estimate the determinants of intercropping based on a survey of 324 households. Smallholders who sold legumes were more likely to intercrop, contrary to literature positing intercropping as a practice primarily intended to enhance food security. In addition, complementary SI practices such as fertilizer, manure and compost application were more likely to have occurred on intercropped fields relative to sole maize fields. Furthermore, smallholder farmers appeared to apply more fertilizer to their intercropped fields relative to their sole maize fields. The study highlights the value of including field-level characteristics and household socioeconomic survey data to understand farming practices as a means to inform agricultural policy.

Abbreviations: SI: sustainable intensification; MLI: maize-legume intercrop; DL: doubled-up legumes     

Effects of intercropping rice and water spinach on net yields and pest control: an experiment in southern China

Strategies encouraging the use of fewer agrochemicals while maintaining high yield are highly demanded for smallholder rice farmers. Intercropping helps to suppress pests and disease in upland farming systems. However, information on the role of intercropping in pest suppression and crop productivity in irrigated rice farming systems is sparse. To explore the possibility of establishing diversified agriculture management strategy that requires lower agrochemical inputs, a field study was conducted to evaluate the effect of rice and water spinach intercropping on the occurrence of pests, disease, and land-use efficiency. Results demonstrated that the occurrence of rice blast disease, sheath blight disease, and Cnaphalocrocis medinalis was substantially lower than pure stands. Compared with rice monoculture, the tiller number, net photosynthetic rate, and leaf chlorophyll content were significantly increased in rice at the edge rows adjacent to water spinach in intercropping. Intercropping increased the per unit area yield of rice without significant reduction in that of water spinach. Land equivalent ratio (LER) was 1.13, showing that intercropping was 13% more productive than rice monocropping. Net income for intercropping was 5.04 times higher than for rice monocropping. These findings suggest that rice and water spinach intercropping is a viable alternative for sustainable rice production with a small farming scale in southern China.     

Exploring farmer perceptions of agricultural innovations for maize-legume intensification in the mid-hills region of Nepal

Maize-legume intercropping is a fundamental component of mixed farming systems in the mid-hills of Nepal. However, its productivity is constrained by several biophysical and social factors, and limited adoption of proven agricultural innovations. In this study, we assessed the productivity impact of a selection of relevant agricultural innovations and changes in the associated perceptions of farmers through a series of two-year participatory on-farm trials. The evaluated innovations resulted in higher yields as compared to farmers' current practices. The active involvement of farmers enlarged our understanding of underlying decision-making factors to adopt or non-adopt agricultural innovations. Additionally, the in-depth farmer engagement in our onfarm trials positively influenced farmer perceptions of the innovations and their interest to adopt the agricultural innovations. Yet, farmers final decisions to adopt some of the evaluated innovations were limited by a host of factors including labour scarcity, the availability of inputs, and by cultural preferences despite the increased yields. This was particularly true for low and medium resource-endowed farmers. This study shows the importance of active farmer participation and context-specific design of research and development projects aiming for local impact.     

Adoption of intercropping among smallholder rubber farmers in Xishuangbanna,China

While the expansion of rubber plantations in the mountainous areas of Southern China has contributed to poverty reduction among the indigenous ethnic groups, the concerns about the associated negatives on ecosystems and sustainable development of livelihoods is rising. One of the measures suggested to reduce environmental and economic risks is rubber intercropping. This study uses cross-section data of some 600 rubber farmers in Xishuangbanna, as a basis to develop four empirical models in order to analyse adoption of intercropping at farm and at plot level. Our study shows that only a small proportion of rubber farmers have adopted intercropping, with tea being the most frequently adopted intercrop. However, we also find that intercropping is an important source of income for the household in the lower income category. Intercropping adoption is affected by ethnicity, household wealth and family labour. The choice of intercrops depends on the nature of rubber plots, the age of rubber trees and geography. This study contributes to a better understanding of the transformation path from rubber monoculture to more diversified, rubber-based agroforestry systems and thus can provide important information for agricultural extension services charged with the promotion of sustainable rubber-based livelihood systems in the Mekong area.     

A meta-analysis of intercropping in Africa: impacts on crop yield,farmer income,and integrated pest management effects

Poverty and hunger in Africa are prevalent and will increase in absolute terms with population growth and continued land degradation. Therefore, there is a need for sustainable agricultural strategies, such as conservation agriculture (CA) and integrated pest management (IPM). Among CA practices, intercropping holds the promise of providing benefits to smallholders through increased crop yields and income as well as improved resource use. We review intercropping’s effects on crop yield, income, and output of IPM practices in Africa. On average, intercropping increases crop yields by 23% and gross income by 172 USD/ha, but effects vary significantly depending on management practices and agro-ecological factors. There was no evidence that yields and gross income for intercropping treatments increase when leguminous intercropping combinations, minimum/reduced tillage, pesticides, or fertilizers were utilized. Dual use of herbicides and intercropping practices garnered 1442 USD/ha more in gross income and yielded 1422 kg/ha more compared to those in conventionally managed fields, signifying the positive influence supplemental inputs can have on intercropping’s effects. Although IPM practices increased yields by 20%, on average, IPM systems integrated with intercropping yielded 24% less than IPM systems that did not. This meta-analysis indicates that intercropping is an advantageous sustainable agricultural practice, but that its effective implementation would depend on considering other factors such as adequate control of competing vegetation. There is a clear need for more scientific studies which examine intercropping’s role in complex sustainable agricultural systems, in order to understand its effects in differential environmental and socioeconomic situations and to optimize the practice’s transfer and benefits.     

坡地果草间作,提高水土保持综合效益

指出坡地单独种植果树对水土保持不利的方面;分析了果树下种牧草对水土保持、培肥地力、形成局部小气候和的促进牧业发展的优越性;林草间作要因地制宜、科学实施。