|
Agricultural productivity is measured as the ratio of agricultural outputs to agricultural inputs.〔Measuring Agricultural Productivity Using the Average Productivity Index (API) by Lal Mervin Dharmasiri ()〕 While individual products are usually measured by weight, their varying densities make measuring overall agricultural output difficult. Therefore, output is usually measured as the market value of final output, which excludes intermediate products such as corn feed used in the meat industry. This output value may be compared to many different types of inputs such as labour and land (yield). These are called partial measures of productivity. Agricultural productivity may also be measured by what is termed total factor productivity (TFP). This method of calculating agricultural productivity compares an index of agricultural inputs to an index of outputs. This measure of agricultural productivity was established to remedy the shortcomings of the partial measures of productivity; notably that it is often hard to identify the factors cause them to change. Changes in TFP are usually attributed to technological improvements.〔Agricultural Investment and Productivity in Developing Countries, FAO Economic And Social Development Paper No. 148, ed. Lydia Zepeda, 2001, FAO Corporate Document Repository, 12 July 2007, http://www.fao.org/docrep/003/X9447E/x9447e00.HTM.()〕 ==Sources of agricultural productivity== Some sources of agricultural productivity are: * Mechanization * High yield varieties, which were the basis of the Green revolution * Fertilizers: Primary plant nutrients: nitrogen, phosphorus and potassium〔http://www.ipni.net/ipniweb/portal.nsf/0/35A687BDB628E999852572050049A51A International Plant Nutrition Institute〕〔http://www.tfi.org/ The Fertilizer Institute〕 and secondary nutrients such as sulfur, zinc, copper, manganese, calcium, magnesium and molybdenum on deficient soil * Liming of acid soils to raise pH and to provide calcium and magnesium * Irrigation * Herbicides * Pesticides * Increased plant density * Animal feed made more digestible by processing * Keeping animals indoors in cold weather See: Productivity improving technologies (historical) Section: 2.4.1: Mechanization: Agriculture, Section 2.6: Scientific agriculture. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「agricultural productivity」の詳細全文を読む スポンサード リンク
|