Article
Computer Science, Information Systems
Ziran Zhang, Steven Glaser, Thomas Watteyne, Sami Malek
Summary: Historically, mountain hydrology research has relied on observational data from infrequent manual measurements, but recent advancements in IoT technology have enabled real-time, cost-effective and dense data collection in this field.
IEEE INTERNET OF THINGS JOURNAL
(2022)
Article
Geosciences, Multidisciplinary
Kehan Yang, Karl Rittger, Keith N. Musselman, Edward H. Bair, Jeff Dozier, Steven A. Margulis, Thomas H. Painter, Noah P. Molotch
Summary: This study validates and compares five SWE datasets in the Sierra Nevada, California, and finds that REC-DA and REC-ParBal models provide the most accurate estimates of SWE in the snowmelt season. The two operational SWE datasets, SNODAS and NWM-SWE, are less accurate. The inter-model comparison also reveals disagreement in snow water storage across time and space.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Ecology
Stefano Casirati, Martha H. Conklin, Mohammad Safeeq
Summary: Higher global temperatures and intensification of extreme hydrologic events, such as droughts, can result in premature tree mortality. In Mediterranean climates like California, the timing of precipitation does not match the peak growing season, and a loss of snowpack during warmer years exacerbates water stress and tree mortality. Using data from the 2012-2015 drought, Regional Generalized Additive Models were used to examine the role of snowpack on forest water stress. The models successfully simulated forest water stress patterns and can help forest managers predict future water stress and tree die-off.
FRONTIERS IN FORESTS AND GLOBAL CHANGE
(2023)
Article
Biodiversity Conservation
Laura C. Streib, Jeffery R. Stone, Eva C. Lyon, Hung H. Quang, Kevin M. Yeager, Susan R. H. Zimmerman, Michael M. McGlue
Summary: This study analyzed lake sediment records from the eastern Sierra Nevada over the past three millennia to reveal ecological changes driven by hydroclimate oscillations. Results showed that hot-dry conditions of the Industrial Era altered lake state, leading to profound impacts on high-elevation lakes and the ecosystem services they provide.
GLOBAL CHANGE BIOLOGY
(2021)
Article
Forestry
Hannah M. Fertel, Malcolm P. North, Andrew M. Latimer, Jan Ng
Summary: Through studying regenerating trees in mixed-conifer forests in the Sierra Nevada of California, we found that the clumped spatial patterns of natural tree recruitment can promote the establishment and early growth of juvenile trees, suggesting a better alternative to common reforestation strategies.
FOREST ECOLOGY AND MANAGEMENT
(2022)
Article
Ecology
James W. Roche, Kristen N. Wilson, Qin Ma, Roger C. Bales
Summary: This study evaluates the uncertainties in water balances across 52 watersheds in the Central Sierra Nevada and highlights the importance of evapotranspiration as a central metric of water-balance change and variability.
FRONTIERS IN FORESTS AND GLOBAL CHANGE
(2022)
Article
Forestry
Hannah M. Fertel, Malcolm P. North, Andrew M. Latimer, Jan Ng
Summary: The study investigated growth rates and spatial patterns among regenerating trees in mixed-conifer forests with restored fire regimes in California's Sierra Nevada. The majority of sampled stems (75%) were found in clumps, and trees growing within clumps grew significantly faster than individual trees growing outside clumps.
FOREST ECOLOGY AND MANAGEMENT
(2022)
Article
Environmental Sciences
Shaun Weatherly, Rebecca Lyons
Summary: This study confirms the presence of 4-NP and its major photolysis product 4-NC in ice and snow, and determines the photolysis parameters and reaction rates. The high detection frequency of 4-NC in snowpack and snowmelt indicates its release to downstream areas. 4-NC is more toxic than its precursor, posing amplified concerns for human and wildlife populations.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Ryan M. Ferrell, Scott Devine, Anthony T. T. O'Geen
Summary: The deep root system of forests allows them to withstand insufficient precipitation. However, there is limited documentation regarding the spatial distribution of regolith thickness in forest ecosystems. A study in the southern Sierra Nevada estimated regolith thickness using hand auger measurements across a 543-ha watershed and found that more than 55% of the area had a depth greater than 5 m. The study also revealed a correlation between topography and spatial trends in regolith thickness.
VADOSE ZONE JOURNAL
(2023)
Article
Microbiology
Mia R. Maltz, Chelsea J. Carey, Hannah L. Freund, Jon K. Botthoff, Stephen C. Hart, Jason E. Stajich, Sarah M. Aarons, Sarah M. Aciego, Molly Blakowski, Nicholas C. Dove, Morgan E. Barnes, Nuttapon Pombubpa, Emma L. Aronson
Summary: Dust provides significant input of nutrients in ecosystems, and is also a vector for dispersing microorganisms. This study found that the composition and diversity of dust-associated microorganisms differ by elevation and are influenced by landscape topography and droughts in source areas.
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Environmental Sciences
Steven Pestana, Jessica D. Lundquist
Summary: Thermal infrared imagery from GOES satellites provides an opportunity to observe mountain surface temperatures. Orthorectification is necessary to correct for the parallax effect in off-nadir imagery. ABI brightness temperatures closely match those of forest canopy temperatures.
REMOTE SENSING OF ENVIRONMENT
(2022)
Article
Forestry
Micah C. Wright, Phillip van Mantgem, Nathan L. Stephenson, Adrian J. Das, Jon E. Keeley
Summary: The study found that seed production by Abies increased immediately following dry summer conditions during a drought year, while seed production by Pinus was higher during warm spring weather at pollination, and seed production by Calocedrus showed a negative association with wetter conditions two years prior to seed production. Tree basal area was found to be a positive factor influencing seed output across all genera.
FOREST ECOLOGY AND MANAGEMENT
(2021)
Article
Biochemistry & Molecular Biology
Yi-Ming Weng, David H. Kavanaugh, Sean D. Schoville
Summary: The evolutionary histories of alpine species are closely related to their response to glaciation, with population structure influenced by drainage basins. Taking into account species' ecological preferences is crucial for understanding their response to climate fluctuations.
Article
Ecology
Margarita Huesca, Susan L. Ustin, Kristen D. Shapiro, Ryan Boynton, James H. Thorne
Summary: This study used airborne hyperspectral imagery to identify the most important wavelength regions predicting drought-induced tree mortality in blue oak woodlands. The best metric for predicting canopy stress was found to be a normalized ratio using specific spectral bands, with a correlation of R-2 = 0.83. The study also revealed that tree mortality prediction accuracy was highest between 1% and 10% mortality rates.
Article
Environmental Studies
Bryant C. Baker, Chad T. Hanson
Summary: There is debate about the effectiveness of commercial thinning as a wildfire management strategy, with conflicting studies on the severity of thinned forests during wildfires. Our study in the Caldor Fire of 2021 found significantly higher cumulative severity in commercially thinned areas compared to unthinned forests. Further research is needed to determine if this pattern holds true for other large wildfires in the western US.
Article
Biodiversity Conservation
Xiaoxia Zhao, Yanjun Su, Tianyu Hu, Mengqi Cao, Xiaoqiang Liu, Qiuli Yang, Hongcan Guan, Lingli Liu, Qinghua Guo
Summary: Accurate quantification of grassland structural and functional traits is crucial for grassland management and restoration. UAV lidar technology is recognized as an accurate and effective technique for estimating vegetation traits at a local to regional scale. However, in grassland ecosystems, UAV lidar data loss is more prevalent at the canopy tops, which significantly impacts the estimation accuracy of grassland traits.
ECOLOGICAL INDICATORS
(2022)
Article
Environmental Sciences
Yanjun Su, Qinghua Guo, Hongcan Guan, Tianyu Hu, Shichao Jin, Zhiheng Wang, Lingli Liu, Lin Jiang, Ke Guo, Zongqiang Xie, Shazhou An, Xuelin Chen, Zhanqing Hao, Yuanman Hu, Yongmei Huang, Mingxi Jiang, Jiaxiang Li, Zhenji Li, Xiankun Li, Xiaowei Li, Cunzhu Liang, Renlin Liu, Qing Liu, Hongwei Ni, Shaolin Peng, Zehao Shen, Zhiyao Tang, Xingjun Tian, Xihua Wang, Renqing Wang, Yingzhong Xie, Xiaoniu Xu, Xiaobo Yang, Yongchuan Yang, Lifei Yu, Ming Yue, Feng Zhang, Jun Chen, Keping Ma
Summary: The complexity of China's vegetation community varies spatially and temporally, influenced by factors such as elevation, temperature, precipitation, and human activities. Despite the observed greening trend, the complexity of China's vegetation community has been decreasing over the past 30 years. Climate warming has a significant negative correlation with vegetation community complexity, but this correlation differs among biogeographical regions. While human activities have a negative influence on vegetation community complexity, vegetation conservation and restoration efforts can help maintain complexity.
Article
Geography, Physical
Kai Cheng, Yanjun Su, Hongcan Guan, Shengli Tao, Yu Ren, Tianyu Hu, Keping Ma, Yanhong Tang, Qinghua Guo
Summary: This study used multi-source remote sensing images and crowdsourced samples to create the first high-resolution map of China's planted forests. The findings show that China's planted forests account for 31.30% of the world's total planted forests, with the majority located in the Eastern, Center-South, and Southwestern regions. The analysis of image features revealed that temporal features are crucial for identifying forests in East and Center-South China, while structural and textural features are more useful for locating forests in North and Northeast China.
ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING
(2023)
Article
Plant Sciences
Ziyang Peng, Yuntao Wu, Lulu Guo, Lu Yang, Bin Wang, Xin Wang, Weixing Liu, Yanjun Su, Jin Wu, Lingli Liu
Summary: Understanding how plants adapt to spatially heterogeneous phosphorus (P) supply is crucial for studying the impact of environmental changes on ecosystem productivity. The relative P limitation to plants was found to be higher in tropical forests than in temperate forests, but varied among species and within sites. Ecosystems develop a coupled aboveground-belowground strategy to maintain P supply and N : P stoichiometric balance under P-limitation.
Article
Biochemical Research Methods
Jingrong Zang, Shichao Jin, Songyin Zhang, Qing Li, Yue Mu, Ziyu Li, Shaochen Li, Xiao Wang, Yanjun Su, Dong Jiang
Summary: This study compares traditional height measurement with four advanced 3D sensing technologies and finds that all 3D sensing data sources have high correlations with field measurement. The prediction accuracy between different data sources decreases in subgroups of canopy height, leaf area index, and growth stage. Canopy height shows high heritability, with 3D sensing datasets having even higher heritability than field measurement. The results provide novel insights into different methods for canopy height measurement that may ensure high-quality application of this important trait.
Article
Multidisciplinary Sciences
Qin Ma, Jian Lin, Yang Ju, Wenkai Li, Lu Liang, Qinghua Guo
Summary: Individual tree structure mapping is important for urban environmental studies. However, there is limited research on spatially explicit mapping of individual trees and their three-dimensional structure. In this study, a dataset of 6,005,690 individual trees in New York City was produced, including tree locations, height, crown area, crown volume, and biomass. The mapping was done using remotely sensed data and field measurements. The dataset enables the evaluation of ecosystem services provided by urban forests and can inform urban forest management and policy making.
Article
Plant Sciences
Zhenhua Sun, Arunkamon Sonsuthi, Tommaso Jucker, Arshad Ali, Min Cao, Feng Liu, Guanghong Cao, Tianyu Hu, Qin Ma, Qinghua Guo, Luxiang Lin
Summary: Tropical forests are important for carbon storage and biodiversity, but their structure can vary due to various factors. This study used field inventory and remote sensing to investigate the effects of canopy and stand structural attributes on aboveground biomass (AGB) in Chinese tropical forests. The results showed that top-of-canopy height, stem size variation, and abundance positively influenced AGB, and increased top-of-canopy height indirectly contributed to greater AGB through increased stem size variation.
Review
Multidisciplinary Sciences
Lingli Liu, Emma J. Sayer, Meifeng Deng, Ping Li, Weixing Liu, Xin Wang, Sen Yang, Junsheng Huang, Jie Luo, Yanjun Su, Jose M. Grunzweig, Lin Jiang, Shuijin Hu, Shilong Piao
Summary: Grassland, despite being one of the largest terrestrial biomes, is facing degradation and desertification due to global climate change and land-use intensification. The carbon cycle in grasslands plays a crucial role in maintaining ecosystem services, and its processes are influenced by abiotic factors such as soil inorganic C accumulation, photodegradation, thermal degradation, and wind erosion. Climate and land-use changes further affect the grassland carbon balance by modifying water budget, nutrient cycling, and plant and soil processes. It is important to prioritize research on abiotic processes, improve monitoring techniques, and select suitable plant species to develop sustainable grassland restoration strategies in a changing climate.
FUNDAMENTAL RESEARCH
(2023)
Article
Multidisciplinary Sciences
Xiaoxia Zhao, Yuhao Feng, Kexin Xu, Mengqi Cao, Shuya Hu, Qiuli Yang, Xiaoqiang Liu, Qin Ma, Tianyu Hu, Maggi Kelly, Qinghua Guo, Yanjun Su
Summary: Grasslands are important coupled human-nature terrestrial ecosystems, but human-induced declines in grassland ecosystem function have been reported. This study explored the role of canopy structure in regulating grassland ecosystem functions in relation to plant species diversity. Field data and satellite remote sensing were used to measure aboveground net primary productivity (ANPP) and resilience, while terrestrial laser scanning data were used to measure canopy structure. The results showed that plant species diversity was positively correlated with canopy structural traits, and canopy structure was a significant indicator for ANPP and resilience. Additionally, the study found that plant species diversity indirectly influenced ANPP through changes in canopy structure. Canopy structure should be considered in future grassland monitoring and management.
FUNDAMENTAL RESEARCH
(2023)
Article
Agronomy
Yang Liu, Ralph Trancoso, Qin Ma, Philippe Ciais, Lidiane P. Gouve, Chaofang Yue, Jorge Assis, Juan A. Blanco
Summary: In order to accurately estimate the size of forest carbon pools and identify the factors affecting them, national forest inventory data and additional field plots were used to estimate carbon storage and density in the Greater Khingan Mountains. From 1999 to 2018, there was an increase in vegetation carbon storage and density, with trees having the highest carbon stocks. The total carbon density in forest ecosystems was influenced by mean annual temperature, with positive effects observed below a certain temperature and negative effects observed above it. Natural and anthropogenic disturbances had weaker effects on carbon density compared to temperature and precipitation.
AGRICULTURAL AND FOREST METEOROLOGY
(2023)
Letter
Zoology
Hai-Tao Yang, Shun Li, Rong Hou, Wen-Tao Song, Yan-Wen Fu, Yong-Bo Li, Xiao-Wei Wang, Gang He, Colin A. Chapman, Qing-Hua Guo, Bao-Guo Li
ZOOLOGICAL RESEARCH
(2023)
Article
Environmental Sciences
Mingtao Xiang, Chiwei Xiao, Zhiming Feng, Qin Ma
Summary: Fire occurrence is closely related to terrestrial ecosystems and plays a significant role in the Earth system. This study combines active fire and land cover data to examine the spatiotemporal patterns and types of active fires at global and continental scales. The findings reveal that active fires predominantly occur in forests and croplands, driving the conversion of forests to croplands. These results have important implications for agricultural expansion, urban safety, carbon sequestration, and biodiversity conservation.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Agronomy
Zurui Ao, Fangfang Wu, Saihan Hu, Ying Sun, Yanjun Guo, Qinghua Guo, Qinchuan Xin
Summary: This study develops a method based on convolutional neural networks (CNNs) and morphological characteristics to accurately extract 3D phenotypic traits of maize plants from LiDAR data. The method shows high accuracy in the segmentation of organs and plants, enabling high-throughput research on plant structural and functional phenomics in field environments.