Article
Environmental Sciences
Dawei Xu, Cong Wang, Jin Chen, Miaogen Shen, Beibei Shen, Ruirui Yan, Zhenwang Li, Arnon Karnieli, Jiquan Chen, Yuchun Yan, Xu Wang, Baorui Chen, Dameng Yin, Xiaoping Xin
Summary: The study evaluated the AGB estimation model using the normalized difference phenology index (NDPI) and found it to be superior in model robustness, spatial, and temporal scalability, making it advantageous for monitoring AGB in large grasslands with significant spatial-temporal heterogeneity.
REMOTE SENSING OF ENVIRONMENT
(2021)
Article
Environmental Sciences
Chiwei Xiao, Peng Li, Zhiming Feng, Yumei Lin, Zhen You, Yanzhao Yang
Summary: The study presented a phenology-based method for mapping rubber plantations and validated it in Xishuangbanna. With support from phenological algorithm and meteorological data, the resultant rubber plantation map achieved a high overall accuracy of 92.3%, enriching remote sensing-based approaches for mapping rubber plantations.
GEOCARTO INTERNATIONAL
(2021)
Article
Multidisciplinary Sciences
Leonardo Fiusa de Morais, Ana Clara Rodrigues Cavalcante, Deodato do Nascimento Aquino, Felipe Herminio Meireles Nogueira, Magno Jose Duarte Candido
Summary: This study utilized remote sensing to analyze spectral responses and land cover change in fragments of Caatinga biome, showing higher SRB in infrared band and lower SRB in red and blue bands in Ouricuri. The classification model had high accuracy in detecting land cover changes in Ouricuri and Taua, indicating its effectiveness in identifying areas most affected by degradation and generating political support for conservation efforts in the Caatinga Biome.
SCIENTIFIC REPORTS
(2021)
Article
Environmental Sciences
Marcelo-Alejandro Doussoulin-Guzman, Fernando-Juan Perez-Porras, Paula Trivino-Tarradas, Andres-Felipe Rios-Mesa, Alfonso Garcia-Ferrer Porras, Francisco-Javier Mesas-Carrascosa
Summary: Plant phenology, influenced by climate conditions, is a sensitive indicator for predicting changes in ecosystems. By studying the evolution and changes in plant phenology and analyzing the correlations between vegetation indices (VIs) and climatic variables, this study found that climatic conditions in Biobio have become more conducive to grassland growth over the period of 2001-2020.
Article
Biodiversity Conservation
Yusong Tang, Rui Chen, Jiangliu Xie, Dujuan Ma, Changjing Wang, Cong Wang, Qiaoyun Xie, Gaofei Yin
Summary: Leaf senescence velocity (LSV) plays a crucial role in regulating carbon and nutrient cycles within terrestrial ecosystems. In this study, we examined the LSV in the Tibet Plateau and found that it is influenced by climate drivers and has significant implications for vegetation growth and carbon exchange. Understanding the interactions between vegetation growth and climate change is important for advancing our knowledge in this field.
ECOLOGICAL INDICATORS
(2023)
Article
Geosciences, Multidisciplinary
Ziqi Chen, Yanhong Zhang, Peng Zang, Zhaoli Liu, Wenbin Zhao
Summary: In this study, red-edge spectral remote sensing data acquired from the Jilin-01 satellite were used to form the Grassland Quality Index (GQI) for assessing grassland quality in the flooded plain in western Jilin Province. The GQI was validated using field measurement data, and the results showed that 80% of grasslands in Xianghai Nature Reserve were of medium quality, with approximately 15% having good growth status mainly in wetland and swamp areas. The evaluation results were verified using survey field biomass, showing a high correlation coefficient of 0.96, indicating good consistency. This study is significant for the monitoring of grassland growth and the development of livestock husbandry in northern China.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Environmental Sciences
William Philpot, Stephane Jacquemoud, Jia Tian
Summary: Identification of materials based on spectral reflectance is complicated by variations in reflectance magnitude caused by local factors. Normalization metrics can help clarify the nature of spectral differences, and normalized difference measures are particularly useful due to their simplicity and ability to be extended to multiple dimensions.
REMOTE SENSING OF ENVIRONMENT
(2021)
Article
Environmental Sciences
Zhiguang Chen, Miaogen Shen, Nan Jiang, Jin Chen, Yanhong Tang, Song Gu
Summary: Daytime warming can delay the end of the vegetation growing season on the Tibetan Plateau, despite the inhibitory effect of low temperatures on alpine vegetation activity. Researchers should take into account the interactive effects of temperature and precipitation on the timing of the growing season when modeling autumn phenology in this region.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Agronomy
Fuyu Yang, Jingjing Xu, Xin Zhao, Xuekai Wang, Yi Xiong
Summary: The implementation of the Grassland Ecological Compensation Policy (GECP) in Qinghai Province has led to dramatic changes in grassland conditions, playing a crucial role in grassland ecological recovery. However, some areas still experience degradation. Despite this, the policy should continue to be implemented to protect grassland ecology and support herders' production activities.
Article
Environmental Studies
Ruifeng Wang, Fengling Shi, Dawei Xu
Summary: This study developed a method for alfalfa mapping using remote sensing data by analyzing the time-series variation characteristics of different vegetation types. The results showed that the number of wave peaks and valleys in the normalized difference vegetation index curve could be used as criteria for alfalfa extraction. The method achieved promising results with high classification accuracy.
Article
Forestry
Jose Luis Gallardo-Salazar, Marcela Rosas-Chavoya, Marin Pompa-Garcia, Pablito Marcelo Lopez-Serrano, Emily Garcia-Montiel, Arnulfo Melendez-Soto, Sergio Ivan Jimenez-Jimenez
Summary: The use of unmanned aerial vehicles (UAV) with multispectral sensors for forest monitoring has increased in recent years. This study analyzed the spectral responses and variations of the normalized difference vegetation index (NDVI) in tree crowns, as well as their correlation with climatic factors. Significant differences in NDVI values were found among different tree species, possibly due to their physiological features and phenology. Quercus grisea had the lowest NDVI values throughout the year, which may be attributed to its sensitivity to relative humidity and temperatures. In more complex forest analyses, the integration of hyperspectral and LiDAR sensors, as well as considering other vegetation indexes, should be considered.
JOURNAL OF FORESTRY RESEARCH
(2023)
Article
Remote Sensing
Shobha K. Yadav, Aaron E. Maxwell
Summary: This study investigates grassland degradation within the Tibetan Plateau using satellite imagery and terrain models. The results show an increase in vegetation growth in the region, particularly in the eastern portion of the plateau. The analysis also suggests that specific grassland types and landforms contribute to this greening trend. However, the correlations between terrain features and vegetation change were found to be modest. Further research is needed to fully understand the dynamics of landscape change in the region.
INTERNATIONAL JOURNAL OF REMOTE SENSING
(2023)
Article
Environmental Sciences
Aakash Thapa, Teerayut Horanont, Bipul Neupane
Summary: This paper studies various methods to verify farmers' claims for compensation, including analyzing images using NDVI and NDWI, analyzing SAR images using CART, and analyzing mobile photos using CNN. The results of the experiments show that the SAR-based method performs the best in flood and drought detection in terms of accuracy and reliability.
Article
Environmental Sciences
Fen Chen, Tim van de Voorde, Dar Roberts, Haojie Zhao, Jingbo Chen
Summary: This communication discusses the limitations and risks of a commonly used method for detecting ground materials, which relies on setting thresholds for normalized difference indices. The authors critically analyze this method and present experimental results on various spectral libraries and satellite images. They highlight the risk of commission errors and provide suggestions for reducing them.
Article
Environmental Sciences
Chuan Li, Iman Rousta, Haraldur Olafsson, Hao Zhang
Summary: Coastal and lakeside settlements, which are heavily populated, are at immediate risk due to climate change and human activities. This study analyzed the water changes in Chao Lake over the past 30 years using time-series images and water indices. The results showed an increase in each estimated indicator's value over time, with the largest fluctuations observed in winter and the smallest in fall. The study also found a strong correlation between the estimated factors, particularly between GNDVI and NDTI. The findings can contribute to environmental planning and efforts to reduce water pollution and environmental hazards in Chao Lake and other water regions.