Table 3 Analysis results of RSEI principal component from 2001 to 2020.

From: Analysis of ecological quality changes and influencing factors in Xiangjiang River Basin

Index

NDVI

LST

WET

NDBSI

EV(PC1)

ECR (PC1%)

2001

0.434

− 0.656

0.217

− 0.576

0.03

67.3

2002

0.429

− 0.554

0.255

− 0.665

0.02

56.8

2003

0.423

− 0.646

0.269

− 0.574

0.03

76.1

2004

0.464

− 0.622

0.294

− 0.557

0.03

70.7

2005

0.311

− 0.645

0.371

− 0.596

0.03

66

2006

0.378

− 0.597

0.294

− 0.643

0.03

63.7

2007

0.394

− 0.512

0.308

− 0.697

0.03

72.6

2008

0.391

− 0.642

0.296

− 0.589

0.03

63.9

2009

0.453

− 0.568

0.251

− 0.639

0.03

71.3

2010

0.433

− 0.566

0.262

− 0.652

0.03

70.5

2011

0.464

− 0.553

0.214

− 0.657

0.03

73.2

2012

0.465

− 0.602

0.225

− 0.607

0.03

67.9

2013

0.461

− 0.618

0.219

− 0.597

0.03

75.1

2014

0.501

− 0.545

0.189

− 0.644

0.03

66.7

2015

0.522

− 0.408

0.229

− 0.712

0.03

67.1

2016

0.507

− 0.532

0.207

− 0.644

0.03

73.6

2017

0.477

− 0.581

0.235

− 0.615

0.03

74.1

2018

0.507

− 0.516

0.256

− 0.641

0.03

76.5

2019

0.487

− 0.502

0.261

− 0.664

0.03

75

2020

0.435

− 0.571

0.259

− 0.645

0.03

71.2