誰來養活中國：中國糧食需求預測研究

Abstract

隨著新世紀來臨，霸主國似乎也跟著更迭，從美國變為中國，從「中國崩潰論」、「中國威脅論」轉為「中國崛起論」後，中國一舉一動受到各國矚目，中國經濟、社會、文化、環境、政治動見觀瞻，成為各方研究、比較、分析的焦點，各式的官方文告、學界研討會、公聽會、研究報告層出不窮，結果亦迥異；單從人口驟增引發資源破壞的討論，各方以2050年為臨界點，全球人口統計數則有89億至93億不等的差距，對中國人口數16億的「上限」認定，非但中國不再能養活自己，甚至危害全世界等說詞不一而足。 糧食既深具特殊政治意涵，涉及長治久安，亦關係國家獨立自主，自不容小覷。《商君書•墾令》有云：「民不賤農，則國安不殆」，無農不穩，無糧則亂，歷史殷鑑不遠：糧食安全確為國家繁榮富強之基，遂萌預測大陸糧食需求之念，以為本文研究重點，並自聯合國糧農組織（food and agricultural organization）中取得中國大陸1961年-2004年：人均消費量、產地價格、人均所得44筆年資料，實證前經不斷糾正、推導、分析，幾經周折，終萌藉由計量經濟學一般化自我迴歸條件異質性變異數模型（Generalized ARCH Model , GARCH）實證衍生一系列的估計、檢定、預測，希望掌握中國、甚至全世界糧食的供應與價格的敏感性，經ARMA、共整合、ARCH、GARCH、衝擊反應分析、誤差修正模型、線性模型與非線性模型從事多元、密集、嚴謹、精細的檢測，排除殘差、使其無異質變異、無自我相關等障礙後，再針對GARCH與非線性模型的良窳進行假性迴歸比較，以展現模型的優質性，經皓首窮經，所有模型已逐一呈現合宜、不偏、最適、理性常態狀態，具有可預測性及未來性，並得出中國糧食需求長遠穩定發展關係及可持續成長的願景。 根據實證分析研究，可歸納出幾點結論： 前兩期糧食消費量遞減，係產地價格上升所致，甚者出現惜售現象，此因一般物價上漲，大陸糧價未跟著上漲，糧農徒增設備及人工成本，加上聯合國糧農組織經常發佈 糧食短缺，數十個國家面臨飢荒等訊息，本文此刻提出研究，頗有呼應之效。 實證結果發現：中國糧食長、短期發展具穩定性、最小變異線性不偏估計式 (best linear unbiased estimator,BLUE)、有配適性且殘差變異數齊一，亦無自我相關性、故具可預測性與長遠發展關係，乃糧食消費增加，刺激糧食售價的攀升；糧食消費量增加，刺激所得增加。 國際間對中國糧食多就供給面探討之，研究期數多短至五期、十期、二十期，顯見中國改革開放前資料多零碎、不完整、不連貫，惟本研究克服諸多限制，從需求面積極探討，冀望日後成為少數文獻。 早期數據可從聯合國糧農組織FAOSTAT資料庫中獲得，顯然較中國準確、完整。遺憾是，只描述國家總供應；未考慮都市、鄉村，貧窮、富有地區實際變化，在執簡御繁中，數據亦具代表性，即：「中國飲食文化正顯著變化」。 預測結果發現中國糧食消費走勢圖及各項指摽均呈現：「中國機會論」非「中國滅亡論」，故頗值後續探討及深入研究。 探究中國糧食需求敏感性，間接觀測世界糧食價格，進而衡量並提供臺灣農業發展空間及參考方向。

As the coming of the 21st centuries, China is becoming a dominating country in the world; hence, there are many predictions about China's future--'the collapsing of China', 'the threatening of China' and 'the rising of China'. China-related issues have been closely studied worldwide. All kinds of reports provided by different Officials, institutes and private researches can be found. Some of them are predicting that the increase of Chinese population may destroy its ecological equilibrium and China will suffer from famine. as a result, the whole world will be affected. According to China's history, the ample staple food supply has a significant political implication－it is a necessity to governing the country well. If the providing of staple food is well secured, a basis for a prosperous China is promised. This study focuses on observing the trend of China’s staple food demand, and further offer to a reasonable prediction. The models used are：GARCH model, Co-integration model, and forecasting process. The Co-integration model may have a non-linear effect； hence, this study uses both Linear and Non-linear approaches in the Co－integration models. The data used in the study are from the Food and Agriculture Organization (U.N.), 1961－2004. The variables are：Average consumer quantity of major grain, average price of grain, and average income. The empirical results are summarized as follow： Firstly, in the first two periods, the declining of consuming quantity on grain will cause the increase of grain price. The farmer could even hold down his sales. This is due to the commodity price a rise but the grain price doesn't go up as well. Since the price of grain keeps unchanged, the costs on equipment and labor are increasing. Secondly, in this study, China's staple food demand is offered to have both long-term and short-term stability, and it fits the 'best linear unbiased estimator (BLUE)', goodness of fit , hence it is predictable and has long-term developing co-relation--the rise of food consumption causes the rise of food price and the increase of food consumption stimulate the increase of income. Third, many studies on this topic have been made from the supply-side. Most of the investigated periods are within 5-20. However, the Chinese data before China's 'reform' are usually fragmentary, inconsistent and incompleteness. This study overcomes many limitations and obstacles, probe into this topic from the demand-side, in an effort to make it a rare one. Fourth, China's data of the earlier years' can be obtained from database of FAOSTAT. Obviously, it has better credibility and is more comprehensive. It's a pity that it only represents the country's total supply, but the differences between rural vs. urban, poor vs. well-off are not included. What we can conclude from the data is：Over the years, the Chinese' dietary habit has changed significantly. Fifth, according to this investigation, all the indexes are aiming to the same direction：China is having a good opportunity, and is not 'developing to perishing'. However, this topic deserves follow up and further investigation. Finally, this study investigates the sensitiveness of China's staple food demand and observes the price of World staple food as well, then, examines Taiwan agriculture's developing opportunities and provides some recommendations.