R ggplot2绘制比例堆叠面积图线条重叠与横轴处理问题求助

安全阿岳

2026-9-27

代码修正方案

核心问题

你代码中存在变量名混用的错误：相对丰度计算结果保存在S1_RA1中，但后续补全缺失分类单元的complete操作执行在了未正确赋值的Shime1_RA2上，导致不同时间点的物种分类（Taxa）没有对齐，堆叠计算时出现错位、线条重叠的异常。

修正后完整代码

第一步：统一数据预处理流程

library(ggplot2)
library(dplyr)
library(tidyr)
library(RColorBrewer)

# 读取数据并计算相对丰度
RA1 <- read.csv("RA1.csv", header=TRUE)
S1_RA1 <- RA1 %>%
  group_by(Timepoint, Taxa) %>%
  summarise(n = sum(Relative.Abundance)) %>%
  mutate(percentage = n / sum(n)) %>%
  ungroup() %>%
  # 补全所有时间点的全部Taxa，缺失值填充为0，是堆叠面积图正常显示的核心
  complete(Timepoint, Taxa, fill = list(n = 0, percentage = 0)) %>%
  # 可选：去除Taxa字段首尾的空格，避免空格导致同一物种被识别为不同分类
  mutate(Taxa = trimws(Taxa))

# 配置配色
nb.cols <- 16
getPalette <- colorRampPalette(brewer.pal(9, 'Set1'))(nb.cols)

第二步：绘制两种横轴类型的图表

1. 横轴为分类变量

ggplot(S1_RA1, aes(x = factor(Timepoint), y = percentage, fill = Taxa, group = Taxa)) +
  geom_area(position = "fill", colour = "black", linewidth = .5, alpha = .7) +
  scale_y_continuous(name="Relative Abundance", expand=c(0,0)) +
  scale_x_discrete(name="Timepoint (d)", expand=c(0,0)) + 
  scale_fill_manual(values = getPalette) + 
  theme(legend.position='bottom')

2. 横轴为数值变量

ggplot(S1_RA1, aes(x = Timepoint, y = percentage, fill = Taxa, group = Taxa)) +
  geom_area(position = "fill", colour = "black", linewidth = .5, alpha = .7) +
  scale_y_continuous(name="Relative Abundance", expand=c(0,0)) +
  scale_x_continuous(name="Timepoint (d)", expand=c(0,0), breaks = unique(S1_RA1$Timepoint)) + 
  scale_fill_manual(values = getPalette) + 
  theme(legend.position='bottom')