GCSE WJEC Geography: High-Frequency Topics and Common Mistakes | GCSE WJEC 地理高频考点与易错题分析

📚 GCSE WJEC Geography: High-Frequency Topics and Common Mistakes | GCSE WJEC 地理高频考点与易错题分析

Understanding which topics appear most frequently in the GCSE WJEC Geography examination and the typical errors candidates make is essential for effective revision. This guide unpacks the areas where students gain or lose the most marks, providing clear explanations and practical tips. By focusing on these high-frequency themes and addressing common misconceptions, you can sharpen your exam technique and boost your confidence on the day.

掌握 GCSE WJEC 地理考试中最高频的考点以及考生最容易犯的典型错误，对高效复习至关重要。本指南深入剖析学生最容易得分与失分的关键领域，提供清晰的解释和实用技巧。通过聚焦这些高频主题并纠正常见误解，你将能够优化答题技巧，在考试当天信心倍增。

1. River Processes and Valley Landforms | 河流过程与河谷地貌

River landscapes are a cornerstone of the WJEC Unit 1 examination. Candidates must be able to describe and explain processes of erosion, transportation and deposition, as well as the resulting landforms such as waterfalls, meanders and floodplains. A high-frequency question asks students to explain the formation of a specific landform step by step, often using a diagram. Many responses lose marks due to incomplete sequencing or blurred terminology.

河流地貌是 WJEC 单元一考试的核心内容。考生需要能够描述并解释侵蚀、搬运和沉积过程，以及由此形成的瀑布、曲流和泛滥平原等地貌。高频考题往往要求考生分步骤解释某个特定地貌的形成，通常要结合示意图。很多答案因为步骤不完整或术语模糊而失分。

A recurring mistake is confusing hydraulic action with abrasion. Hydraulic action is the sheer force of water breaking rock particles away from the bed and banks, whereas abrasion is the grinding of rock fragments carried by the river against the channel, wearing it away like sandpaper. Students frequently use the terms interchangeably or describe abrasion as the ‘force of water’, which examiners penalise. Ensure you state that abrasion requires the river’s load to be effective.

一个反复出现的错误是混淆水力作用与磨蚀。水力作用是水流的直接冲击力使岩石颗粒从河床和河岸脱离，而磨蚀是指河流携带的岩屑对河道的研磨，就像砂纸一样磨损河道。学生经常互换使用这两个术语，或将磨蚀描述为“水的力量”，这会被考官扣分。务必说明磨蚀需要河流携带的负载才能发挥作用。

When explaining waterfall formation, many candidates skip the crucial role of differential erosion. A complete six-mark answer must state that a band of hard rock lies over softer rock, the softer rock is eroded more quickly by hydraulic action and abrasion, creating an overhang, which eventually collapses, and the plunge pool deepens by swirling debris. Omitting the undercutting of soft rock or the retreat of the waterfall upstream is a common reason for losing half the marks.

在解释瀑布形成时，很多考生会跳过差异侵蚀的关键作用。一个完整的六分答案必须说明：一层硬岩覆盖在软岩之上，软岩因水力作用和磨蚀被更快侵蚀，形成悬垂的凸出部分，最终崩塌，跌水潭因涡流中的碎屑而加深。遗漏软岩被淘蚀或瀑布向上游后退的过程，是丢失一半分数的常见原因。

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2. Coastal Erosion and Landforms | 海岸侵蚀与地貌

WJEC frequently examines coastal processes through named examples and diagrams. High marks depend on the accurate use of terms like longshore drift, constructive and destructive waves, and an understanding of landform evolution. The specification expects candidates to link processes to specific features at a case-study coastline, such as the formation of a stack or a spit.

WJEC 经常通过具体实例和图表来考查海岸过程。高分依赖于准确使用诸如沿岸漂移、建设波和破坏波等术语，并能理解地貌的演变。考试大纲要求考生将过程与案例研究海岸的具体特征联系起来，例如海蚀柱或沙嘴的形成。

The most common error is reversing the sequence that forms a stack. Students might write that a cave forms, then a stack, then an arch, which is incorrect. The correct logical chain is: cracks or joints in the headland are widened by hydraulic action and abrasion → a cave develops → erosion cuts through to form an arch → the roof of the arch collapses due to weathering and gravity → a stack is left isolated. Examiners look for the precise order and the process responsible at each stage.

最常见的错误是颠倒了海蚀柱的形成顺序。学生可能会写先形成洞穴，然后形成海蚀柱，再形成海蚀拱，这是不正确的。正确的逻辑链条是：岬角上的裂缝或节理被水力作用和磨蚀拓宽→形成洞穴→侵蚀贯穿形成海蚀拱→海蚀拱的顶因风化和重力崩塌→孤立的残骸即海蚀柱。考官关注每个阶段的准确顺序及对应的作用过程。

Another frequent slip-up occurs with longshore drift. Many answers correctly state that waves approach the beach at an angle, but then they describe sediment moving straight up the beach and straight back down. The key is that the swash carries material up the beach at the oblique angle of the prevailing wind, while the backwash returns perpendicular to the shoreline under gravity. This zigzag movement transports sediment along the coast. Failing to mention the contrasting directions of swash and backwash typically limits the answer to two marks out of four.

另一个常见失误出现在沿岸漂移的描述上。许多答案正确地指出波浪以一定角度逼近海滩，但随后却描述沉积物直接沿海滩直上直下运动。关键在于，冲流以盛行风的斜向角度将物质带上沙滩，而回流则在重力作用下垂直于海岸线返回。这种之字形运动使沉积物沿着海岸移动。如果不提及冲流与回流方向的不同，答案通常只能在四分中拿到两分。

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3. Weather Hazards and Climate Change | 天气灾害与气候变化

Global atmospheric circulation, tropical storms, and the evidence for climate change are heavily examined in both Unit 1 and Unit 2. Students must be able to interpret climate graphs, explain the distribution of storm hazards, and evaluate management strategies. Marks are frequently dropped because candidates treat ‘weather’ and ‘climate’ as synonyms or fail to use precise evidence for climate change.

全球大气环流、热带风暴以及气候变化的证据在单元一和单元二中都是重点考查内容。学生必须能解读气候图表，解释风暴灾害的分布，并评估管理策略。失分常见的原因包括考生将“天气”和“气候”视为同义词，或未能使用精确的证据说明气候变化。

The most avoidable mistake is writing ‘global warming causes tropical storms to form anywhere that is warm’. Tropical storm formation requires very specific conditions: sea temperatures above 27°C, a location between 5° and 30° north or south of the equator, and sufficient Coriolis force to spin the system. At the equator, the Coriolis effect is too weak, so storms do not form there. Stating ‘they form in warm water’ without mentioning latitude or Coriolis will not reach the higher mark bands.

最可避免的错误是写下“全球变暖导致热带风暴在任何温暖的地方形成”。热带风暴的形成需要非常具体的条件：海面温度高于27°C，位置在赤道南北5°至30°之间，并且需要足够的科里奥利力使系统旋转。在赤道处，科里奥利效应太弱，因此不会形成风暴。只写“它们在温暖水域形成”而不提及纬度或科里奥利力，无法达到高分段的要求。

When using climate graphs, pupils often misread the temperature scale or confuse the precipitation bar chart with the temperature line. A typical mistake is to state that the highest rainfall occurs in the warmest month without checking the two y-axes. Always annotate the axes and write a short description of the annual trend before linking it to the question. For climate change evidence, a generic mention of ‘ice cores’ is insufficient; you must specify that air bubbles trapped in ice cores contain carbon dioxide and reveal past atmospheric composition going back hundreds of thousands of years.

在使用气候图表时，学生经常读错温度刻度，或者混淆降水量柱状图和温度曲线。一个典型错误是没有查看两个纵轴就声称最高降雨发生在最温暖的月份。务必标注坐标轴，并先写下年变化趋势的简短描述，再将其与问题联系起来。对于气候变化的证据，笼统地提到“冰芯”是不够的；你必须明确指出冰芯中封存的气泡含有二氧化碳，可以揭示过去数十万年的大气成分。

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4. Ecosystems and Tropical Rainforests | 生态系统与热带雨林

The structure, nutrient cycle, and sustainable management of tropical rainforests appear consistently across WJEC papers. Questions often ask candidates to explain why soils are infertile despite the lush vegetation or to evaluate strategies such as ecotourism and selective logging. High-scoring answers link the rapid nutrient cycling to the climate and show understanding of interdependence.

热带雨林的结构、养分循环和可持续管理在 WJEC 试卷中反复出现。题目常常要求考生解释为什么植被茂密土壤却很贫瘠，或评价生态旅游和选择性伐木等策略。高分答案会将快速的养分循环与气候联系起来，并表现出对相互依存关系的理解。

A classic error is claiming that rainforest soil is naturally rich because so many plants grow there. In reality, most nutrients in a tropical rainforest ecosystem are stored in the biomass (the living plants), not in the soil. The hot, humid climate causes rapid decomposition, and heavy rainfall quickly leaches minerals from the topsoil. Once the forest is cleared, the thin layer of nutrients is washed away, leaving infertile, latosol soils. Confusing biomass storage with soil storage is a pitfall that appears in almost every exam series.

一个经典错误是声称雨林土壤天然肥沃，因为有大量植物生长。事实上，热带雨林生态系统中大部分养分储存在生物量（活的植物）中，而不是土壤里。炎热潮湿的气候导致快速分解，而强降雨又迅速将表土的矿物质淋溶带走。一旦森林被砍伐，薄薄的养分层就会被冲刷殆尽，留下贫瘠的铁铝土。混淆生物量储存与土壤储存是几乎每届考试都会出现的陷阱。

On the topic of sustainable management, many answers list techniques but fail to evaluate them. For an eight-mark ‘evaluate’ question, describing ecotourism is only half the task. You must also weigh the benefits (employment, conservation funding) against the limitations (limited carrying capacity, possible cultural erosion, money leakage). Similarly, international agreements like REDD+ should be assessed for their strengths and weaknesses. Without a ‘however’ paragraph, the response caps out at level 2.

关于可持续管理这一话题，许多答案只是罗列技术而没有进行评价。对于八分的“评价”题，描述生态旅游只完成了任务的一半。你还必须权衡其益处（就业、保护资金）与局限（有限的承载能力、可能的文化侵蚀、资金外流）。同样，像 REDD+ 这样的国际协议也应该评估其优缺点。如果没有“然而”段落，回答最多只能停留在第二级评分。

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5. Urban Change and Challenges | 城市变迁与挑战

Urbanisation, counter-urbanisation, and the problems of megacities in lower-income countries are staple WJEC themes. Candidates need to refer to named case studies — often a city in the UK and one in a newly industrialising country — and be able to discuss housing, transport, and social inequality. The most common errors stem from mixing up causes and consequences or failing to use specific place details.

城市化、逆城市化以及低收入国家大都市的问题是 WJEC 考试的主题。考生需要引用具体案例研究——通常是一个英国城市和一个新兴工业化国家的城市——并能讨论住房、交通和社会不平等问题。最常见的错误源于混淆原因与后果，或未能使用具体的地点细节。

A high-frequency pitfall is writing generic statements such as ‘air pollution is caused by traffic’ in a case-study question. Examiners want to see local context: for example, ‘In Mumbai, the high density of autorickshaws and outdated engines contributes to particulate matter (PM2.5) levels exceeding WHO limits, particularly in the Dharavi area.’ Using a named location, a specific pollutant, and a place-specific detail elevates the answer from a general answer to a case-study one worth full marks.

一个高频的陷阱是案例分析题中写一些笼统的陈述，如“空气污染由交通引起”。考官希望看到地方背景：例如，“在孟买，高密度的机动三轮车和落后的发动机导致PM2.5浓度超过世卫组织限值，尤其在达拉维地区更是如此。”使用具体的命名地点、特定的污染物和具有地方特色的细节，可以将答案从泛泛而谈提升到值得满分的案例分析高度。

Another common error concerns the reasons for counter-urbanisation. Students often say people move ‘for a better environment’ without unpacking the push and pull factors. A comprehensive explanation should mention the push of urban congestion, high property prices, and perceived crime rates, alongside the pull of a perceived rural idyll, technology enabling remote working, and improved road links. Moreover, distinction must be made between counter-urbanisation (movement to rural areas) and suburbanisation (movement to the urban fringe). Mixing these terms up is a sure way to lose marks.

另一个常见错误涉及逆城市化的原因。学生经常说人们搬家是“为了更好的环境”，却没有分析推拉因素。一个全面的解释应提及城市拥堵、高房价和感知的犯罪率等推力，同时指出对田园生活的向往、远程办公技术的支持以及道路网络的改善等拉力。此外，必须区分逆城市化（搬往乡村地区）和郊区化（搬往城市边缘）。将这两个术语搞混，必然丢分。

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6. Population Dynamics and Structure | 人口动态与结构

The Demographic Transition Model (DTM), population pyramids, and the causes of rapid population growth form a significant part of Unit 2. WJEC expects candidates to interpret pyramid shapes, link them to DTM stages, and discuss the social and economic implications. A perennial mistake is treating the DTM as a rigid timeline that all countries follow identically rather than as a model with limitations.

人口转变模型 (DTM)、人口金字塔和人口快速增长的原因构成了单元二的重要部分。WJEC 希望考生能解读金字塔的形状，将其与 DTM 阶段联系起来，并讨论其社会和经济影响。一个常年存在的错误是将 DTM 视为所有国家都会按相同方式遵循的刚性时间线，而忽略了它作为一个模型的局限性。

When analysing population pyramids, students frequently misidentify the stage by only looking at the overall width of the base. A wide base can suggest stage 2 (high birth rate, falling death rate), but you must also check the sides. If the sides are straight, it indicates many children surviving but still a relatively low life expectancy. If the pyramid shows concave sides (narrower at older ages), it often means a recent reduction in infant mortality and a gradually ageing population, characteristic of stage 3. Without commenting on both the slope of the sides and the proportion of dependents, stage identification is guesswork.

在分析人口金字塔时，学生常常仅通过底部的总体宽度来判断阶段，从而识别错误。一个宽阔的底部可能指向第二阶段（高出生率、死亡率下降），但你还必须检查两侧。如果两侧垂直，说明许多儿童存活，但预期寿命仍然较低。如果金字塔呈凹面侧（老年组明显缩窄），通常意味着近期婴儿死亡率下降，人口逐渐老龄化，这是第三阶段的特征。如果不对侧面坡度与抚养人口比例都进行评论，阶段识别就只是猜测。

For questions on rapid population growth, candidates often list policies (one-child policy, family planning) as a bullet-point list without explaining how these policies influence birth rate components. A top-level answer should explain that improving female education reduces the desire for large families and raises the average age at marriage, directly lowering the fertility rate. Similarly, discussing healthcare improvements without linking them to reduced infant mortality — which then changes parental behaviour regarding family size — misses the chain of causation that examiners reward.

对于人口快速增长的问题，考生经常以点列方式罗列政策（独生子女政策、计划生育），却没有解释这些政策如何影响出生率的构成要素。高分答案应解释：提高女性教育水平会减少对大家庭的渴望并提高平均结婚年龄，从而直接降低生育率。类似地，讨论医疗保健改善却不联系到婴儿死亡率下降——进而改变父母对家庭规模的行为——则错失了考官赏识的因果链条。

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7. Development Gap and Indicators | 发展差距与指标

The measurement of development, causes of global inequality, and strategies to close the gap appear in most WJEC series. Topics include GDP per capita, HDI, the Brandt Line, and the role of trade and aid. A typical mistake is viewing development purely as economic wealth, ignoring social indicators, or describing the development gap as a simple ‘north-south’ divide without contemporary nuance.

发展的衡量标准、全球不平等的成因以及缩小差距的策略在多数 WJEC 考试中出现。主题包括人均 GDP、人类发展指数 (HDI)、勃兰特线以及贸易和援助的作用。一个典型的错误是将发展纯粹视为经济财富，忽视社会指标，或者将发展差距简单地描述为没有当代细微差别的“南北”分界。

The most frequent error when using HDI is failing to acknowledge the three components it measures: life expectancy, years of schooling, and gross national income per capita. Students may claim that a country has a high HDI because it is ‘wealthy’, which is only one part of the index. An oil-rich country with unequal healthcare access might rank lower on HDI than a country with moderate income but excellent social services. A comparative statement using both GDP and HDI always demonstrates a more sophisticated understanding.

在使用 HDI 时最常见的错误是没有明确指出它所衡量的三个组成部分：预期寿命、平均受教育年限和人均国民总收入。学生可能会声称一个国家 HDI 高是因为它“富裕”，但这只是指数的一部分。一个石油丰富但医疗可及性不均衡的国家，其 HDI 排名可能低于一个收入适中但社会服务出色的国家。同时使用 GDP 和 HDI 进行比较陈述，总是能显示更深层次的理解。

When evaluating fair trade as a strategy, many answers are overly simplistic, such as ‘fair trade gives farmers a fair price so it solves the development gap’. The exam expects a balanced view: fair trade guarantees a minimum price and a social premium for community projects; however, the number of certified farmers is small, the premium may not reach the very poorest who cannot afford certification, and it does not structurally change global trade rules. A two-sided evaluation is needed for the higher mark band, especially in an ‘assess’ or ‘evaluate’ question.

在评估公平贸易这一策略时，许多答案过于简单，例如“公平贸易给农民一个公平的价格，所以它解决了发展差距”。考试期望的是一种平衡的观点：公平贸易保证最低价格和用于社区项目的社会溢价；然而，获得认证的农民数量很少，溢价可能无法惠及那些无力承担认证费用的最贫困人群，而且它并未在结构上改变全球贸易规则。要想在高分段得分，特别是在“评估”或“评价”类题目中，必须进行双面评价。

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8. Tectonic Hazards and Management | 地质构造灾害与管理

Plate boundaries, the distribution of earthquakes and volcanoes, and hazard management are essential knowledge. WJEC often asks candidates to explain why people live in hazard-prone areas and to contrast responses in countries of differing wealth. The differentiation between immediate and long-term responses and between prediction and protection is a hurdle for many.

板块边界、地震与火山的分布以及灾害管理是必备知识。WJEC 经常要求考生解释人们为何居住在灾害多发区，并对比不同富裕程度国家的应对措施。短期响应与长期响应的区别，以及预测与防护之间的区别，是许多学生的障碍。

The most common misconception involves the relationship between plate boundaries and volcanic types. Students may claim that explosive composite cone volcanoes are found at constructive plate margins, when in fact these are typical of destructive margins where subduction causes silica-rich magma. Constructive margins, such as the Mid-Atlantic Ridge, produce effusive basaltic eruptions and shield volcanoes. Confusing constructive with destructive plate boundary volcanism instantly signals a fundamental misunderstanding to the examiner.

最常见的误解是板块边界与火山类型之间的关系。学生可能声称爆炸性的复式锥形火山位于建设性板块边界，而实际上它们在俯冲造成富硅岩浆的破坏性板块边界更为典型。建设性板块边界，如中大西洋海脊，产生的是溢出性玄武岩喷发和盾形火山。将建设性与破坏性板块边界的火山活动搞混，立即向考官表明存在根本性的误解。

When contrasting hazard responses, weak answers only list the effects in two countries rather than comparing the responses. For instance, after an earthquake, a high-income country (HIC) might use instant seismic detection to shut down gas pipelines and deploy search teams within hours, whereas a low-income country (LIC) may rely on international aid that takes days, and limited medical capacity leads to higher secondary deaths. The use of a specific comparison of monitoring, preparedness, and speed of reaction separates grade 8-9 candidates from the rest.

在对比灾害应对措施时，薄弱的答案往往只罗列两个国家的影响，而没有比较应对措施。例如，地震发生后，高收入国家可能利用即时地震检测关闭天然气管道并在数小时内派出搜救队，而低收入国家可能依赖数日后才能到达的国际援助，有限的医疗能力导致更高的次生死亡人数。具体比较监测、备灾和反应速度，能够使 8-9 等级的考生脱颖而出。

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9. Geographical Skills and Cartography | 地理技能与制图

Cartographic and graphical skills permeate all three WJEC units. Map-reading, interpretation of OS maps at 1:50 000 scale, and the accurate use of compass directions and grid references are frequently tested. A significant number of marks are lost each year because students misread map symbols or fail to give a six-figure grid reference when required.

地图制图与图形技能贯穿 WJEC 全部三个单元。地图阅读、对 1:50 000 比例尺的英国地形测量地图的解读，以及正确使用罗盘方向和网格坐标，都是经常考查的内容。每年有相当多的分数因为学生读错地图符号或没有按要求给出六位数网格坐标而丢失。

The most basic but repeated error is counting the wrong way for grid references. The rule ‘along the corridor and up the stairs’ means the eastings come first (the numbers along the bottom) and the northings second (the numbers up the side). When giving a six-figure reference, students must imagine each grid square divided into tenths — an estimation skill many find difficult under pressure. Practice with real OS map extract questions is the only remedy. Also, describing a location as ‘north of the river’ without naming the feature or using a compass point relative to a settlement does not meet the precision needed.

最基本却又反复出现的错误是网格坐标的读取顺序错误。“横走道纵楼梯”的口诀指明向东的坐标值在先（底部数字），向北的坐标值在后（侧边数字）。给出六位数坐标时，学生必须想象每个网格方格被分成十分之一——这项估算技巧让很多人在考试压力下感到困难。用真实的 OS 地图片段进行练习是唯一的补救方法。此外，将位置描述为“河北岸”而没有说出特征名称或使用相对于某聚落的罗盘方向，无法满足所需的精度。

On graph interpretation, a common slip is using raw data without manipulation. If a question asks whether there is a relationship between GDP and life expectancy based on a scatter graph, a single sentence quoting the correlation is low-level. Instead, read figures, calculate the range, identify anomalies, and state the general trend with data support. For maps showing isolines, a frequent error is drawing a smooth curve that ignores obvious kinks in the data; the line must interpolate between known points while respecting the correct spacing.

在图表解读方面，一个常见失误是使用未经处理的原始数据。如果一道题根据散点图询问 GDP 与预期寿命之间是否存在关系，仅用一句话引用相关性是低水平的。你应该读取数据，计算极差，识别异常值，并基于数据支持陈述总趋势。对于显示等值线的地图，一个常见错误是绘制一条平滑曲线而忽略了数据中明显的曲折；连线必须在已知点之间进行插值，同时尊重正确的间距。

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10. Fieldwork Enquiry and Data Analysis | 实地考察探究与数据分析

Unit 3 is entirely dedicated to the fieldwork enquiry, and WJEC candidates must be thoroughly familiar with their own investigations. The exam requires describing the methodology, presenting data, and drawing conclusions with evaluation. The most frequent slip is failing to separate the conclusions from the evaluation, resulting in a repetitive answer that does not meet the mark scheme requirements for reflection.

单元三专门针对实地考察探究，WJEC 考生必须对自己进行调查的方法了如指掌。考试要求描述方法、展示数据，并得出结论与评价。最常见的失误是未能将结论与评价区分开来，导致答案重复，不符合评分方案对反思的要求。

In the methodology section, students often list equipment without justification. For example, writing ‘we used a tape measure to measure the width of the river’ earns only a basic mark. To move up, you must say ‘we used a 30-metre tape measure held taut and perpendicular to the channel to ensure accurate and consistent width measurements at each of the ten sites, allowing comparison along the long profile.’ The detail of the sampling strategy — systematic, random, or stratified — and why it limited bias is essential for quality of methodology marks.

在方法部分，学生经常只罗列设备而不说明理由。例如，写“我们用了卷尺测量河流宽度”只能拿到基础分。要升级，你必须说“我们使用了一条 30 米长的卷尺，拉紧并垂直于河道，以确保在十个采样点获得准确一致的宽度测量值，从而能够沿下游纵剖面进行比较。”采样策略的细节——系统、随机或分层——以及它如何限制偏差，是拿到方法论质量分数的关键。

Regarding conclusions, the common error is simply repeating the data without explaining the geographical reasons. If your hypothesis was ‘velocity increases with distance downstream’, do not just say ‘the velocity rose from 0.25 m/s to 0.64 m/s’. Explain that the increase is likely due to reduced roughness from a smoother channel bed and a decrease in wetted perimeter relative to cross-sectional area, which reduces friction and allows more efficient flow. Then, link back to the Bradshaw model. In evaluation, many candidates write ‘we could have taken more measurements’, which is too vague. Specify ‘measuring at an additional two sites in the upper course would have clarified whether the initial steep increase in velocity was an anomaly or part of the trend.’ Anomalies should be identified and possible reasons suggested.

关于结论，常见的错误是只重复数据而不解释地理原因。如果你的假设是“流速随下游距离而增加”，不要只说“流速从 0.25 m/s 升至 0.64 m/s”。要解释这种增长可能是因为河道底面变平顺使得粗糙度降低，以及湿周长相对于横截面积减小，从而减少摩擦，使水流更有效。然后，联系布拉德肖模型。在评价部分，许多考生写“我们可以多做些测量”，这太过模糊。要具体说明：“在上游增加两个采样点可以澄清初始的流速急升是异常值还是趋势的一部分。”应该识别异常值并提出可能的原因。

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