Improved tree fallows in smallholder maize production in Zambia: do initial testers adopt the technology?
Improved tree fallows in smallholder maize production in Zambia: do initial testers adopt the technology?
复制标题
赞比亚小农玉米生产的树木休耕得到改善：初始测试人员是否采用了该技术？
DOI：
10.1007/s10457-004-2410-0
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发表时间：
2005
影响因子：
2.2
通讯作者：
S. Franzel
中科院分区：
文献类型：
--
作者：
A. Keil;M. Zeller;S. Franzel
在赞比亚东部，人口增长导致人均土地供应量减少，以至于无法再实行传统的灌木休耕，土壤肥力低下是作物生产的主要制约因素。基于豆科树木的改良休耕（IF）是一种低现金投入的农林业做法，旨在恢复土壤肥力。本文报告的研究目的是评估测试该技术的农民对该技术的采用情况，包括该技术相对于其潜在规模的实施程度。使用纠正样本选择偏差的两阶段赫克曼回归模型来估计影响发生率和采用规模的社会经济和农业生态决定因素。 75% 的测试者采用了该技术，这表明，在南部非洲大部分地区普遍存在资本稀缺、肥料市场准入不足以及人口密度相对较低的情况下，IF 是一种合适的做法。采用者将该技术实践到了其潜在规模的 42%；财富与发生率以及采用规模之间存在非线性关系；土地和劳动力的供应限制了进一步的扩张。因此，未来的农场研究应强调减少土地和劳动力需求的 IF 选项，例如将 IF 物种与玉米间作，以及可以直接播种的 IF 物种。
In eastern Zambia, population growth has reduced per-capita land availability to such an extent that traditional bush fallows can no longer be practiced, and low soil fertility is a major constraint to crop production. Improved fallows (IF) based on leguminous trees are a low cash-input agroforestry practice to restore soil fertility. The objective of the study reported here was to assess the adoption of IF by farmers who tested the technology, including the extent to which the technology is practiced relative to its potential scale. The socioeconomic and agroecological determinants of the incidence and scale of adoption are estimated using a two-stage Heckman regression model that corrects for sample selection bias. Seventy-five percent of the testers have adopted the technology, which shows that IF are a suitable practice under conditions of capital scarcity, inadequate access to markets for fertilizer, and relatively low population density, which prevail in large parts of southern Africa. Adopters practice the technology to 42% of its potential scale; a non-linear relationship was found between wealth and the incidence as well as the scale of adoption; land and labor availability limit further expansion. Hence, future on-farm research should emphasize IF options which reduce land and labor requirements such as intercropping IF species with maize, and IF species which can be seeded directly.