Shozei (the rice tax stored in provincial offices warehouse) (正税)
Shozei (Taizei) refers to tokoku (rice grains plucked off the straws, with chaff on) and eito (reaped rice plants holding grains) stored in shoso (public repository) in ryoseikoku (province) under the ritsuryo system (a system of centralized government based on the ritsuryo code). Sometimes it refers to only the part of suiko honto (rice equivalent to principal of suiko [government loans made to peasants]) of them. It was mainly consisted of the yearly yield of tax and the interest on suiko from shozei.
Summary
Shozei was supposed to be allotted to the following. It was used as suiko honto (as mentioned above, the increased part of shozei becomes interest).
In Heian period, sometimes, only this part was called 'shozei.'
As fudokoku (staples for an emergency), it was stored in shoso in kokuga (provincial government office compounds) and gunga (county government offices) (the ideal amount was 30 years' worth of denso [rice field tax] income [equivalent to yearly yield]).
It was allotted to the running cost of local administration such as clerical expense and salary of government officials.
Expenses incurred in the purchase of tribute articles to give to the central government and for the transportation of land taxes and the tribute articles.
The yield of tax was mainly allotted to fudokoku staple as tokoku (when needed, it was allotted to the emergency expense for disaster and famine, and the fund to refill or enhance the eito), and the interest on suiko was to suiko honto and sundry expenses as eito (shozeito [rice paid as shozei] or suikoto [loaned rice plant]).
Establishment of shozei
Shozei, initially called 'taizei,' appeared in 691 during the period of Asukakiyomihararyo (the legal code of Japanese ancient state). It is not clear, despite the various theories, about its connection to gunto (rice stored in a county) that used to belong to kori (provincial administrative organization), and the relation to miyake (a governing system in Yamato sovereignty [the ancient Japan sovereignty]) that was older than the first, but it can be considered that land tax, suiko and hyoto (rice in kori) stored in miyake and Kuninomiyatsuko-ryo (territory of the heads of local governments) were integrated or separated into taizei and gunto in the process of reorganization after the Taika Reforms.
After the establishment of Taiho Ritsuryo (Taiho Code), taizei was put under the control of Minbusho (Ministry of Popular Affairs), then, in 708, the system of Fudokoku staple was put in operation. On the other hand, apart from this, 'kanto' (rice gathered as denso and stored in various provinces) such as gunto, koyoine and ekikito (rice harvested from ekiden [rice field provided by government, exempted from tax] to allot to the cost of stations in Yoro-ryo [Yoro Code]) was established. However, kanto below gunto was integrated into taizei with the change of its formal name to 'shozei' in 734, and ekikito that had been considered exception was also integrated in 739. This is called 'kanto kongo' (mixed kanto) in the field of historical studies. Afterward, it was unified to shozei, so the word 'taizei', which used to be used in conjunction with the word 'kanto', also died out. Incidentally, as an episode showing the abundance of shozei at the time, Daijokanpu (official documents from Daijokan to local governments) dated August 31, 808 compiled in "Sandairuijukyaku" (a law code) tells that, in 740, Fudokoku staple of shoso that had never been put outside to respect the regulations was found decomposed one after another, so that an order was issued to replace the old rice by the same volume of new rice.
Collapse of shozei
However, in 744, for building Kokubun-ji Temple and Kokubun-ni-ji Temple, each ryoseikoku (province) was ordered a senyu (offer something to a temple) of 20 thousand bunches of shozei to provide each temple respectively as well as a diversion of suiko interest into construction costs. In the following year, Kugaito (rice as local source of revenue) was established with the fund diverted from shozei; 4 hundred thousand bunches from Taigoku (major provinces), 3 hundred thousand bunches from jogoku (second-biggest provinces next to Taigoku), 2 hundred thousand bunches from chugoku (middle sized provinces) and 1 hundred thousand bunches from gekoku (minor provinces), thus, suiko which was supposed to be allotted to kokushi's salary began to be set separately from shozei. Then, kokushi began to focus on suiko of kugaito connected with their income, leading to the consequence of the growth of provincial finances while the control of shozei began to be neglected. In addition, the Imperial Court focused on ensuring that there was a sufficient quantity of fudokoku, and they tried to cover the cost of this with shozei, even though it was supposed to be made up with tributes to the central government. Therefore, they introduced 'nenryo shomai' (rice made by pounding it in a mortar and paid in kind for the taxes) and 'nenryo betsuryo sokoku' (denso stored in shoso separately from fudokoku to supply in case of central government's financial difficulties) that could bring them extra eito, and 'nenryo soshomai' (tax payment in milled rice) that could cover tairomai (rice given to low-ranking staff under the Ritsuryo system) with eito of shozei, accordingly, a large amount of shozei brought in the central government. Besides, the corruption of local governments became more critical as reflected on the shoso burned out by sacred flame, therefore, shozei in each province was running short rapidly ('Shozei yojin'). Thus, in Heian period, Imperial Court began to launch political measures to recover the shozei for the purpose of maintaining the tribute-to-central system, such as introduction of 'shozei ritsubun (the tax system where two-tenth of the tax delivered from the provinces to the Ministry of Finance at Heian-kyo [the ancient capital of Japan in current Kyoto] were supplied to the tax storage called "ritsubun-do")' that made up the shortage of shozei with the interest on kugaito and establishment of 'shozei shikisu' in which kokushi's minimum liability for shozei suiko (compulsory loaning to and collecting repayments from peasants) was prescribed in kyakushiki (a kind of law in the ritsuryo system). However, the decline of the ritsuryo system and the unpaid land tax and suiko led shozei system to the virtual corruption in the mid Heian period.