Spatiotemporal dynamics of soybean crop in the Matopiba region,Brazil (1990–2015)

Brazil is a world leader in the production and export of grains, particularly soybeans. The newest agricultural frontier in Brazil is the Matopiba region, which is a continuous zone formed by the states of Maranhão, Tocantins, Piauí, and Bahia, located mostly within the Cerrado biome. The objective of this study was to analyze the spatiotemporal dynamics of soybean production and yield in the Matopiba region. We analyzed municipality-based planted areas and production data obtained by the Brazilian Institute of Geography and Statistics during 1990–2015. Yield was estimated from the production and planted area, and the data were analyzed using global and local Moran indices. The results showed that soybean production in the Matopiba region does not occur randomly. Positive and significant autocorrelation was found at the beginning of the time series among those municipalities located in the west of Bahia. This region influenced the soybean expansion from south to north. Currently, high-production areas are concentrated in two autocorrelated blocks: one in western Bahia and the other in the central Matopiba region. Analysis of spatial autocorrelation involving yield showed a decreasing trend at the end of the time series. The presence of municipalities with high yield surrounded by others with low yield, and vice-versa, were observed. The findings of this study could assist local and regional agricultural planning in the Matopiba region, and support related analyses in other fields of agriculture, the environment, and logistics.     

中国大豆生产和贸易

This paper provides an overview of the economic analysis, policy debate, and methodological issues on soybean production, import and export, and impacts of GMO regulation on soybean foreign trade of China. The paper analyzes China's soybean production capability and discovers that the present yield of China's soybean plant system cannot satisfy the domestic demand. The paper also provides the method to solve such matters by using the result of a modified Cobb-Douglas model. In the third section of this paper, the impacts of GMO regulation on soybean trade and market in China are analyzed. In this section, we provide a methodological issue to analyze the impacts of such regulation on trade. The paper then explains the implicated result induced by such regulations.     

大豆多肽研究概况

大豆肽是大豆蛋白水解后,由3～6个氨基酸残基组成的低肽混合物,分子量在1000Dalton左右。由于它具有很多优良的理化特性和生理活性,因此有很多领域得到了广泛的应用。本文简要综述了这方面的研究进展。     

数量化理论模型在大豆食心虫虫食率的预测中的应用

大豆食心虫的危害程度是由虫食率来决定的,影响大豆食心虫虫食率的因素很多,以往对虫食率的预测方法只是基于定量变量,并且要求预测数据准确,然而影响害虫的危害程度的因素除定量因素外,还有许多定性因素,本文考虑影响大豆食心虫虫食率的定量因素:上年平均脱荚孔数、上年9月(中下旬)平均气温、上年9月份(中下旬)降水量、上年10月份(上旬)降水量、当年7月份平均气温、当年7月份降水量以及当年7月份湿度作自变量和定性因素:大豆品种、幼虫越冬存活率和8月分平均百米蛾量(观测误差较大的数据做为定性变量来考虑),以当年的虫食率作为基准变量建立数量化理论模型,增加了数据资料信息的应用,取得了精确的预测结果,对实际工作有一定的指导意义。     

土壤温度对大豆产量的影响试验研究

通过对大豆进行盆栽试验,来研究不同土壤温度对大豆各发育阶段及其产量的影响,从中找出提高土壤温度与大豆产量的关系,从而对充分利用气候资源提高大豆产量有着重要的指导作用。     

Producing biodiesel from soybeans in Zambia: An economic analysis

Facing a huge fiscal burden due to imports of its entire petroleum demand in the face of ample supply of agricultural land to produce biofuels, Zambia has recently introduced a biofuel mandate. However, a number of questions, particularly those related to the economics of biofuels, have not been fully investigated yet. Using an empirical model, this study analyzes the economics of meeting the biodiesel mandate using soybean oil. The study finds that meeting the biodiesel mandate would reduce social welfare, mainly because of the welfare loss to fuel consumers and net reduction in foreign exchange earnings due to soybean oil imports. However, if Zambia increases its domestic soybean supply, as well as oil yield, soybean-based biodiesel is likely to be welfare-beneficial. The country’s welfare is found to be the highest under expanded soybean production and its domestic processing but with no biodiesel mandate.     

我国大豆市场价格整合分析

主要研究国内大豆市场之间、国内与国际大豆市场之间的价格影响与作用机制。本文分析了各市场价格变化之间的因果关系,各市场之间相对价格差异调整的速度。并从计量经济学的模型检验了变量价格序列数据之间是否是协整的关系及确认了它们之间格兰杰意义上的因果关系走向。     

Do oil prices drive food prices? The tale of a structural break

It is frequently argued that biofuel (and ethanol) promotion policies in the United States have created a link between oil and corn prices that has accentuated the recent rally in the price of that crop and its substitutes (especially soybeans). Even though it is intuitively appealing, one problem with this hypothesis is that ethanol policies have been in place in the US for more than 35 years, whereas the run up in food prices dates back only to 2006. However, a significant change in US biofuel policy during that year provides an adequate framework to test for the existence of a structural break in the stochastic properties of the corn and soybean price processes. The results show that structural stability is rejected, and the transmission of oil price innovations to corn prices has become stronger after 2006 (no changes with respect to soybeans). There is also a significant transmission of corn price innovations to oil and soybean prices. Moreover, the data show evidence of a previously non-existent cointegration relationship between oil and corn prices.     

An interdisciplinary model of soybean yield in the Amazon Basin: The climatic, edaphic, and economic determinants

Soybean production is one of the main economic forces driving the expansion of the agricultural frontier in the Brazilian Amazon. To assess the potential for expansion we estimate a model of soybean yield that integrates the major climatic, edaphic, and economic determinants in the Amazon Basin. Yield is modeled as a function of yield as simulated by a crop physiology model that captures the effects of climate and physical attributes on the development of soybean plant; fertilizer applications; and economic/spatial parameters such as credit, transports costs and latitude. Current values of these determinants indicate that roughly 20% of Amazon Region or ∼ 1,000,000 km² (excluding protected areas) can generate yields greater than 2000 kg/ha. Soybean production may be possible over a wider area of Amazon, but realizing this potential requires improvements in economic determinants such as the transportation infrastructure.     

中国与国际大豆期货市场波动溢出效应分析

文章采用多元GARCH(MGARCH)模型,研究中国、美国和日本大豆期货市场的相关性和波动溢出效应。结果表明:在样本研究期间,大连、芝加哥和东京大豆期货交易市场之间存在正相关,大连大豆期货市场与芝加哥大豆期货的相关性要小于东京谷物交易所大豆期货与芝加哥大豆期货的相关性;大连、芝加哥和东京大豆期货交易所存在双向的波动溢出效应;在三个市场中,大连大豆期货的新息冲击和自身波动溢出值最小,但在统计上不显著,可能与目前大连期货市场受管制和相对封闭等因素有关;三个大豆期货市场市场均不存在波动持续性。