MIS2阶段是末次冰期中最寒冷的冰阶，开始于29ka cal BP，并在~26.5-18ka cal BP达到峰值，为末次盛冰期。MIS2阶段尤其是末次盛冰期，全球冰盖大规模扩张，海平面下降约130m，地表气温平均下降约8-10℃，造成北半球气候带和植被带大幅南移。古人类在面对MIS2阶段气候极端变冷事件时的技术与行为适应是旧石器时代考古学研究的重要课题。但是，由于中国南方地区的遗址面临着年代测定困难和石制品数量相对较少等问题，学界对这一地区MIS2阶段古人类石器工业和生存行为的认识仍相对有限。

上湖遗址是中国南方地区新近发现的一处旧石器时代旷野遗址，出土了丰富的石制品（n=6200）。其中，第1、2层出土的6066件石制品是本文的主要研究对象，年代始于距今约 2.6 万年前；第3层出土少量石制品（n=134），但尚不清楚其埋藏原因，因此暂不将它们纳入本研究。另外，在上湖遗址所在的高安盆地也发现了其它20余处旧石器遗址，可能与上湖遗址共同构成了一个大致同时期的遗址群。

本文主要以上湖遗址出土的石制品为研究对象，采用区域原料调查、技术类型学和拼合分析等研究方法，揭示上湖遗址石器工业特征。在此基础上，结合对石器技术组织的分析和GIS空间分析，研究上湖遗址古人类流动策略及其对MIS2阶段环境的适应性。最后，从区域对比研究和适应性的角度，探讨上湖遗址石制品细小化成因。本文对上述问题的研究，已取得初步认识。

石器工业特征：上湖遗址石制品整体展现出显著的细小化特征。原料以脉石英为主（95.09%），其它原料均占比较少，其中又以燧石原料的比例相对较高（2.82%）。脉石英等砾石原料和燧石分别采自遗址附近的河滩和距离遗址10km范围内、埋藏于地表或近地表的燧石产地，其它小众原料在遗址附近也均可找到。古人类在采备砾石原料时，对砾石的尺寸和质地进行了挑选。燧石原料节理发育、易破碎的特征可能是古人类没有大量使用燧石原料的主要原因。古人类利用石核毛坯的原料类型、原始形态、尺寸和质地等，发展出了多样化的剥片策略，其中以单面单向剥片和向心剥片为主。石核剥片主要以剥取长15-25mm、宽10-20mm和厚5-10mm的细小石片为主。工具组合以刮削器为主，辅以凹缺器、锯齿刃器、钻和尖状器等类型。工具的修理方式为锤击法。工具的加工程度有限，对毛坯尺寸和形态的改造程度较小。制作工具时，对尺寸稍大一些和质地更加优质的毛坯进行了挑选。从工具的尺寸来看，大部分工具表现出了细小化特征（63.39%）。古人类在开发和利用原料的各个阶段，均体现着对优质原料的选择倾向。

流动策略：上湖遗址石制品技术组织、高安盆地内遗址分布模式和景观要素的分析显示，MIS2阶段古人类可能采取了一种偏后勤式流动的策略，以位于斑块边缘、视觉优势最为突出的上湖遗址作为中心营地，采取裂变-融合的形式，通过派遣任务小组，从事有计划的狩猎采集活动。任务小组在外活动时，可能也会有临时性营地和功能性场所，这些位置通常临近锦江或其支流，是两种环境资源斑块的交界地带，资源更为丰富和多样，古人类可能从这里狩猎或采集资源，并将获取到的资源带回中心营地。上湖遗址古人类的这种活动模式可能代表了较低的群体流动性和较高的个体流动性。

上湖遗址古人类采取了一种偏后勤式移动的生计策略，可能是为了适应MIS2阶段极端气候事件导致的资源分布不均和可预测性降低等风险，而做出的策略选择。同时上湖遗址的石制品细小化可能是在旧石器时代晚期中国南方地区，甚至更大范围内石制品细小化的技术演化背景下，古人类适应其流动策略而有目的、有意识地发展出来的。另外，上湖遗址与中国南方地区其它呈现细小化特征的遗址之间，石器工业存在有一些不同点，主要为燧石原料在石制品组合中占比较少，以及石核剥片策略的独特性，这些不同点可能是源于古人类对原料内部结构、质地和外部形态的适应差异。

The MIS2, starting at 29 ka cal BP, is the coldest ice stage in the last glacial period, and peaked at ~26.5-18 ka cal BP known as the Last Glacial Maximum (LGM). During MIS2, especially the LGM, the global ice sheet expanded massively, the sea level dropped by about 130 m, the surface temperature dropped by about 8-10°C on average, and the climatic and vegetative zones of the northern hemisphere moved significantly to the south. The technological and behavioral adaptations of ancient humans to the extreme cooling event during MIS2 are important issues in Paleolithic archaeology. However, due to dating difficulties and the relatively small number of stone artifacts in southern China, our understanding of the lithic industries and subsistence behaviors of ancient humans during the MIS2 in this region is still limited.

The Shanghu site is a newly discovered open-air Paleolithic site in southern China, with abundant stone artifacts (n=6200). Among them, the 6066 stone artifacts excavated from the first and second layer are the main research objects of this paper, dating from about 26,000 years ago. A small number of stone artifacts (n=134) were unearthed in the third layer, but their taphonomy cause is not clear, so they are not included in this study. In addition, more than 20 other Paleolithic sites have been found in Gao'an Basin, where the Shanghu site is located. These sites may form a roughly contemporaneous site group with the Shanghu site.

This paper primarily focuses on the stone artifacts from the Shanghu site, using the methods of regional raw material investigation, techno-typology, and refitting analysis to reveal the characteristics of the lithic industry at Shanghu site. Building on this analysis, we combine technological organization theory and GIS spatial analysis methods to study the mobility strategies of ancient humans at the Shanghu site and their adaptability to MIS2 environment. Finally, we discuss the causes of the lithic miniaturization at the Shanghu site. In this paper, a preliminary understanding of the above problems has been obtained.

Lithic industry characteristics: The stone artifacts from the Shanghu site show a significant miniaturization characteristic as a whole, The raw material is mainly vein quartz (95.09%), while other raw materials account for a small proportion, among which the proportion of chert is relatively high (2.82%). The cobbles were collected from nearby river beaches, while chert was quarried from within 10 km of the site. Other minor raw materials can also be found near the site. Ancient humans selected cobbles for their size and texture. The joint development and fragile characteristics of chert may be the main reason why ancient humans did not use chert in large quantities. The ancient humans employed various flaking strategies based on the raw material types, original shapes, sizes, and textures of the core blanks, among which unifacial unidirectional flaking and centripetal flaking were dominant. The primary aim of core flaking was to produce miniaturized flakes with a length of 15-25 mm, width of 10-20 mm, and thickness of 5-10 mm. The tool assemblage was dominated by scrapers, supplemented by notches, denticulates, borers and points. The freehand hard hammer technique was primarily used for retouching tools. The retouching degree of tools was limited, and there was little modification on the original shape and volume of  tool blanks. When making tools, a slightly larger size and better texture blank was selected. In terms of tool size, most tools showed miniaturization characteristics (63.39%). The ancient humans preferred high-quality raw materials at all stages of development and utilization.

Mobility strategies: The analysis of the technological organization at the Shanghu site, site distribution patterns and landscape features in the Gao’an Basin suggest that the hominins during the MIS2 may have adopted a logistical mobility strategy. Shanghu site, which is located at the edge of a patch with outstanding visual advantages, was used as a base-camp. The hominins may have employed a fission-fusion pattern and dispatched task groups to engage in planned hunting and gathering activities. When the task groups were active in the field, they may have also set up temporary camps and functional locations near the Jinjiang river or its tributaries, which served as the intersection zone of two environmental resource patches, with richer and more diverse resources. The hominins likely hunted or gathered resources from these areas and brought them back to the base-camp. This activity pattern at the Shanghu site may represent lower group mobility and higher individual mobility.

The logistical mobility strategy adopted by hominins at the Shanghu site may have been a strategic choice to adapt to the risks associated with the uneven distribution and reduced predictability of resources caused by extreme climatic events during the MIS2. At the same time, the lithic miniaturization at the Shanghu site may have been developed purposefully and consciously by hominins adapting to their mobility strategies under the background of the lithic technology evolution during the late Paleolithic in southern China, or even a larger region. Furthermore, there are some differences between the lithic industry at the Shanghu site and other sites with lithic miniaturization in southern China, primarily in the lower proportion of chert raw materials in the lithic assemblage and the uniqueness of the core reduction strategy. These differences may be attributed to the differences in adaptation to the internal structure, texture, and external shape of raw materials by ancient humans.