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Sustainability Of Sown Pastures In The Tropics And Subtropics, Jose M. Toledo, Daniel Formoso

IGC Proceedings (1977-2023)

Sown pastures in the tropics and subtropics are important components of production systems. Their role in and contribution to land productivity and economic development are well understood; however, their roles in sustainability and environmental protection are rather misunderstood and little known. The main constraints to sustainability of sown pastures fall into two categories: physical, biological and technical constraints include soil and climatic limitations, lack of adaptation of plants to physical and biotic stress and the limitations of farmers or ranchers to apply technology; socioeconomic factors include political instability, poorness of society and the market forces for land, inputs and products. …

Stability In Rangelands: Ecology And Economics, B H. Walker

IGC Proceedings (1977-2023)

Examples of changes in rangelands are presented relating to changes in livestock number, plant species. composition and soil changes (associated with changes in production), The mechanisms Involved are described, using examples, under the headings: event-driven change, threshold effects, non-linear and hysteresis effects, effects of spatial variation, significance of temporal variation, and interactive effects. The implications for management are presented in the form of a proposed optimal control model which maximises a complex function of welfnre based on long-term net economic benefit, in which stocking rate effects on the state of the rangeland feed back on to economic return.

Diffendal Receives Wisherd Award For University Service, Ronica Stromberg

Robert F. Diffendal, Jr., Publications

Even though he’s retired, Robert Diffendal seems to be working everywhere.

The professor emeritus in the School of Natural Resources retains offices in three buildings. He reports to work at the Center for Great Plains Studies five days a week for about four hours a day. His list of volunteer activities around the state goes on and on, affecting, by his count, 21,088 people since 2003, when he stepped away from full-time faculty work. He capped 2024 at Nebraska Innovation Campus, where he received the Wisherd Award for Outstanding Service to the University of Nebraska–Lincoln.

Chosen by the Emeriti and …

Expedition 395 Summary, R. E. Parnell-Turner, A. Briais, L. J. Levay, Y. Cui, A. Di Chiara, J. P. Dodd, T. Dunkley Jones, D. Dwyer, D. E. Eason, S. A. Friedman, S. R. Hemming, K. Hochmuth, H. Ibrahim, C. Jasper, B. T. Karatsolis, S. Lee, D. E. Leblanc, M. R. Lindsay, D. D. Mcnamara, S. E. Modestou, B. Murton, S. Oconnell, G. T. Pasquet, P. N. Pearson, S. P. Qian, Y. Rosenthal, S. Satolli, M. Sinnesael, T. Suzuki, T. Thulasi Doss, N. J. White, T. Wu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The intersection between the Mid-Atlantic Ridge and Iceland hotspot provides a natural laboratory where the composition and dynamics of Earth's upper mantle can be observed. Plume-ridge interaction drives variations in the melting regime, which result in a range of crustal types, including a series of V-shaped ridges (VSRs) and V-shaped troughs (VSTs) located south of Iceland. Mantle upwelling beneath Iceland dynamically supports regional bathymetry, and its variations may lead to changes in the height of oceanic gateways, which in turn control the flow of deep water on geologic timescales. Expeditions 384, 395C, and 395 recovered extensive successions of basaltic crust …

Site U1554, R. E. Parnell-Turner, A. Briais, L. J. Levay, Y. Cui, A. Di Chiara, J. P. Dodd, T. Dunkley Jones, D. Dwyer, D. E. Eason, S. A. Friedman, S. R. Hemming, K. Hochmuth, H. Ibrahim, C. Jasper, B. T. Karatsolis, S. Lee, D. E. Leblanc, M. R. Lindsay, D. D. Mcnamara, S. E. Modestou, B. Murton, S. Oconnell, G. T. Pasquet, P. N. Pearson, S. P. Qian, Y. Rosenthal, S. Satolli, M. Sinnesael, T. Suzuki, T. Thulasi Doss, N. J. White, T. Wu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

No abstract provided.

Site U1555, A. Briais, R. E. Parnell-Turner, L. J. Levay, Y. Cui, A. Di Chiara, J. P. Dodd, T. Dunkley Jones, D. Dwyer, D. E. Eason, S. A. Friedman, S. R. Hemming, K. Hochmuth, H. Ibrahim, C. Jasper, B. T. Karatsolis, S. Lee, D. E. Leblanc, M. R. Lindsay, D. D. Mcnamara, S. E. Modestou, B. Murton, S. Oconnell, G. T. Pasquet, P. N. Pearson, S. P. Qian, Y. Rosenthal, S. Satolli, M. Sinnesael, T. Suzuki, T. Thulasi Doss, N. J. White, T. Wu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

No abstract provided.

Scaling Arctic Landscape And Permafrost Features Improves Active Layer Depth Modeling, Wouter Hantson, Daryl Yang, Shawn P. Serbin, Joshua B. Fisher, Daniel J. Hayes

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Tundra ecosystems in the Arctic store up to 40% of global below-ground organic carbon but are exposed to the fastest climate warming on Earth. However, accurately monitoring landscape changes in the Arctic is challenging due to the complex interactions among permafrost, micro-topography, climate, vegetation, and disturbance. This complexity results in high spatiotemporal variability in permafrost distribution and active layer depth (ALD). Moreover, these key tundra processes interact at different scales, and an observational mismatch can limit our understanding of intrinsic connections and dynamics between above and below-ground processes. Consequently, this could limit our ability to model and anticipate how ALD …

Landslide Susceptibility Assessment Of The Wanzhou District: Merging Landslide Susceptibility Modelling (Lsm) With Insar-Derived Ground Deformation Map, Chao Zhou, Lulu Gan, Ying Cao, Yue Wang, Samuele Segoni, Xuguo Shi, Mahdi Motagh, Ramesh P. Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

The prevalent catalog-based Landslide Susceptibility Modelling (LSM) operates under the assumption that future landslide occurrences mirror past and current patterns. Due to growing urban expansion and climate change, certain landslides follow new patterns of occurrence, disrupting the foundational assumption of catalog-based LSM and leading to constraints in the effectiveness of traditional susceptibility maps. Here, to address this problem, we proposed a method to produce more accurate and dynamic landslide susceptibility maps by coupling advanced Ensemble Machine Learning (EML) and Multi-Temporal Interferometric SAR (MT-InSAR). The Wanzhou District in Three Gorges Reservoir area of China is considered as the test site. The …

Coal Mining-Induced Composite Damage To Geological Bodies And Geological Guarantee Against Damage Reduction, Wang Shuangming, Sun Qiang, Hu Xin, Geng Jishi, Hou Enke, Wang Shengquan, Zhou Shutao, Shi Qingmin, Yuan Shihao, Chen Kai, Song Shijie

Coal Geology & Exploration

Objective and Background Coals have long served as a predominant energy source in China. With an increase in mining scale and intensity in recent years, the correlations between rocks, soils, hydrosphere, and ecological environment in coal mining areas have been strengthened. Given this, there is an urgent need to, from the perspective of Earth system science, understand the coupling relationships and chain characteristics among factors including the movement and deformations of surrounding rocks, rock bursts, coal and gas outbursts, water inrushes, ground subsidence, water and soil erosion, and damage to ecological environments, aiming to achieve safe, green coal mining. Methods …

Impacts Of Coal Fracture Roughness And Aperture On The Seepage Of Injected Water: An Experimental Study, Wang Gang, Chen Xuechang, Chen Hao, Long Qingming, Liu Yixin

Coal Geology & Exploration

Objective Water injection into coal seams is recognized as a critical technical measure for dust removal and the prevention and control of coal and gas outbursts and rock bursts in coal mines. The effectiveness of this measure is significantly influenced by the morphological characteristics of fractures, such as their roughness and aperture. Methods This study prepared coal samples containing fractures with different roughness and apertures using sandpaper and polyimide tape, calculated the fracture roughness parameters accurately using a confocal laser scanning microscope (CLSM), and tested the seepage rate of fractured coal samples. Results and Conclusions The results indicate that the …

Fracture-Seepage Characteristic Zones Of The Overburden Of Extra-Thick Coal Seams: Evolutionary Patterns And Their Engineering Applications, Kong Xiangguo, Zhao Tianshuo, Lin Haifei, Zhao Pengxiang, Wang Xu, Cai Yuchu, Ji Pengfei, He Di, Li Ke, Xu Chuanyu

Coal Geology & Exploration

Objective and Methods Given that the overburden’s structure significantly influences pressure relief gas extraction, this study aims to explore the gas migration patterns of the overburden of thick coal seams during coal seam mining. To this end, this study analyzed the evolutionary patterns of the fracture morphology and seepage capacity of the overburden using physical similarity simulation experiments. Accordingly, this study investigated the mechanisms behind the evolution of fracture-seepage characteristic zones of the overburden of extra-thick coal seams and proposed a method for identifying fracture-seepage characteristic zones of the overburden. Using this method, this study conducted gas extraction along the …

A Key Technology For Synergistic Backfilling Of Coal-Based Solid Waste And High-Salinity Wastewater, Dong Shuning, Yu Shujiang, Dong Xingling, Zhang Buqin, Guo Xiaoming, Wang Xiaodong, Wang Kai, Zhu Shibin, Wu Boqiang, Liu Lei

Coal Geology & Exploration

Background and Objective Limited by locations, as well as economic and technical levels, most of the coal-based solid waste is still accumulated in the form of open-air landfills without treatment, thus occupying large quantities of land resources and causing secondary pollution to the environment. The proper treatment and reduction of high-salinity wastewater (e.g., high-salinity mine water and high-salinity water from the coal chemical industry) represent a key link in the achievement of zero liquid discharge. However, existing technologies for high-salinity wastewater treatment are generally confronted with issues such as great initial investment and high operation costs of the treatment engineering. …

Experimental Study Of The Piezoelectricity Of Middle Pleistocene Loess In The Weibei Region, China, Jing Yanlin, Liu Jie, Liu Qingying, Duan Xiaoxiao, Xie Na, Yang Dengke

Coal Geology & Exploration

Objective Quartz, the piezoelectric material discovered the earliest, has found widespread applications in industry, military fields, and daily life due to its piezoelectricity. The widely distributed loess worldwide is composed primarily of quartz, accounting for 37.0% to 69.9%. However, there is a lack of studies on the piezoelectricity of loess both domestically and internationally. Methods This study investigated the ${\mathrm{Q}}_2^{{\mathrm{eol}}} $ loess from the Weibei Loess Tableland in Shaanxi Province as an example to explore the piezoelectricity of loess. The piezoelectric coefficient of the loess was measured, and its piezoelectric voltage under the action of static loading and vibration was …

Deformations And Seepage-Induced Erosion Of Fractured Rocks In Fault Under Confined Settings, Sun Wenbin, Tian Dianjin, Ma Cheng, Xue Yanchao, Yang Can, Zhu Kaipeng

Coal Geology & Exploration

Objective Most of the mining areas in China have entered the deep mining stage. In this case, the risks of mine water inrushes increase significantly due to the complex deep hydrogeological conditions, a significant increase in the number of hidden disaster-causing factors, and the existence of faults. Methods Using a deformation-seepage experiment system for fractured rocks, this study investigated the characteristics of compressive deformations and seepage-induced erosion of fractured rocks in faults. By analyzing the impacts of particle-size distribution combinations, saturation state, and seepage pressure, on the deformation-permeability characteristics of fractured rocks under confined axial compression, this study investigated the …

Characteristics Of Cenozoic Volcanic Edifices In The Pingnan Area, Xihu Sag, Sun Naiquan, Jiang Donghui, Pan Jie, Gao Yang, Pu Renhai, Dong Xinxu

Coal Geology & Exploration

Significance Igneous rocks are well-developed in the southern Pinghu slope zone, Xihu Sag, East China Sea Shelf Basin. In this zone, the increased local geotemperature caused by magmatic activity produced significant impacts on the thermal evolution of source rocks and the formation of secondary pores in sandstone reservoirs and also serves as a significant indicator of regional tectonic movements, thus holding great significance for understanding the regional geological history. Objective and Methods This study aims to determine the formation stages and distribution patterns of igneous rocks as the cap rocks in the southern Pinghu slope zone. Using previous study results …

An Intelligent Lithology Identification Method For Sandstone And Mudstone Strata And Its Applications: A Case Study Of The Jurassic Strata In The Lunnan Area, Xinjiang, China, Cai Ming, Zhou Qingwen, Yang Cong, Chen Feng, Wu Dong, Lin Wang, Zhang Chengguang, Zhang Yuanjun, Miao Yuxin

Coal Geology & Exploration

Objective Lithology identification lays the foundation for fine-scale reservoir evaluation. However, traditional identification methods generally utilize the interactive relationships between only 2‒3 logging parameters, suffering from low utilization rates of logging information and low identification accuracy for strata with small differences in logging responses. This seriously restricts the effects of old well reexamination. The efficient, intelligent CatBoost classification algorithm can fully mine the correlations between multi-source logging information and lithology. Methods This study investigated the Jurassic sandstone and mudstone reservoirs in the Lunnan area, Xinjiang, China. Using five logging parameters determined through sensitivity analysis, i.e., natural gamma-ray value, spontaneous potential, …

A Dehazing And Enhancement Algorithm For Heterogeneous Images Of Underground Mining Environments In Coal Mines, Zhang Xuhui, Xie Yanbin, Yang Wenjuan, Zhang Chao, Wan Jicheng, Dong Zheng, Wang Yanqun, Jiang Jie, Li Long

Coal Geology & Exploration

Objective In coal mines, the uneven distribution of dust haze and complex illumination conditions caused by underground coal mining and dust removal lead to blurred video images, as well as the loss of information and details. Hence, this study proposed a dehazing and enhancement algorithm for heterogeneous images of underground mining environments. Methods Initially, hazy images were segmented into zones with different brightness values, for which the average ambient light intensity of global dark channels was calculated. The calculation results were integrated through weighting with the ambient light of local bright channels, which was obtained using adaptive gamma correction and …

Prospects For Mine Geological Work In The Intelligence Age: Architecture Of The Intelligent Geological Guarantee Technology System For Mine Exploitation, Xia Yucheng, Sun Xueyang, Miao Lintian, Guo Chen, Du Rongjun

Coal Geology & Exploration

Background and Significance In response to the serious challenges posed by the goals of peak carbon dioxide emissions and carbon neutrality, the intelligentization of coal mines is an inevitable course and a significant sign of the high-quality, sustainable development of the coal industry in the New era. Mine geological work, providing geological foundation and guarantee for underground coal mining, plays an increasingly significant role in the transformation and upgrading of the coal industry for high-quality development. Constructing an intelligent geological guarantee technology system for coal mining by combining mine geology with artificial intelligence (AI) can provide a comprehensive, whole-process geological …

An Analytical Method For The Desorption Superposition Effect In Commingled Production Of Coalbed Methane And Its Application: A Case Study Of The Xiaotun Mine Field In Western Guizhou Province, China, Guo Chen, Ji Yan, Zhao Chenyi, Lu Lingling, Yu Xinhang, Gao Junzhe, Li Houqiang, Zhang Xuyang, Wang Xiang, He Hongbin, Zhang Runhan

Coal Geology & Exploration

Objective The commingled production of coalbed methane (CBM) serves as a significant means to increase single-well production. However, production practices reveal that the commingled production of CBM exhibits complex and varied effects and controlling factors, facing technical challenges of identifying gas-producing contributions, predicting gas-producing potential, and optimizing pay interval combinations. The superposition of desorption for gas production among different coal seams determines whether high CBM production can be achieved using commingled production. Methods This study proposed an analytical method for the desorption superposition effect in the commingled production of CBM, involving determining desorption sequences, analyzing the superposition of desorption intervals …

Optical-Electrical-Acoustic Wave Multiparameter Response Characteristics Of Typical Rocks In Coal-Bearing Strata Throughout The Loading Process, Zhang Pingsong, Liu Chang

Coal Geology & Exploration

Objective The deformations and rupture of rocks under loading will cause potential changes in parameters. Dynamic parameter capture assists in characterizing the generation, propagation, and closure processes of fractures, serving as a significant method for assessing rock quality. Methods Using a multiparameter test system, this study synchronously acquired strain measured using distributed optic fibers, electrode current, and compressional wave (P-wave) velocities of rock specimens under uniaxial loading. Accordingly, this study determined strength vs. parameter characteristic relationship graphs and parametric tomography results, finely describing the multiparameter spatiotemporal evolutionary characteristics of three typical rocks (i.e., sandstone, limestone, and mudstone) throughout the loading …

A U-Net-Based Denoising Method For Semi-Airborne Transient Electromagnetic Data And Its Application, Liu Dong, Feng Hao, Wang Yongxin, Zhou Xiaosheng, Yao Yuhong, Sun Huaifeng

Coal Geology & Exploration

Objective and Methods The semi-airborne transient electromagnetic (SATEM) method, an efficient geophysical exploration technique, has been extensively applied to mineral resource exploration, groundwater surveys, and geothermal resource surveys. However, the collected data are frequently susceptible to noise interference, significantly affecting the accuracy of subsequent data processing and interpretation. To address issues such as residual noise and the loss of effective signals, enhance denoising effects, and reduce the influence of subjective factors, this study proposed a denoising method for SATEM data based on the U-Net deep learning architecture (also referred to as the U-Net-based method) by applying U-Net to SATEM data …

China’S Cbm Exploration And Production And Associated Technological Advancements: A Review And Reflections, Ye Jianping

Coal Geology & Exploration

Objective and Methods Based on extensive scientific and technical literature and technical data on coalbed methane (CBM) exploration and production projects, this study conducted a comparative analysis of the development process and latest advances in China’s critical technologies for CBM exploration and production and reviewed the CBM exploration and production history of this country over the past three decades. Accordingly, this study discussed the theoretical and technical challenges in CBM exploration and production and proposed future development directions. Advances The results indicate that the insights into conversion between adsorbed and free deep CBM prove to be a significant theoretical understanding. …

Critical Technologies And Geology-Engineering Integration Practices For Deep Cbm Production In The Yanchuannan Cbm Field, Chen Zhenlong, Wang Yunhai, Liu Xiao, Cui Bin, Yang Song, Li Xin, Fang Qilong

Coal Geology & Exploration

Objective and Methods This study introduces the adjustments for coalbed methane (CBM) production in the Yanchuannan CBM field‒the first deep CBM field in China. Deep CBM production in this CBM field faces challenges including strong heterogeneity of reservoirs, single arrangement mode of production well patterns, low applicability of conventional hydraulic fracturing, excessively long conventional production cycles, and a high proportion of inefficient wells. To address these challenges, a production capacity construction model for efficient deep CBM production of the field was developed through in-depth geology-engineering integration. Results and Conclusions The results indicate that the production capacity construction process of the …

Connotation, Research Status, And Development Directions Of Clean Coal Geology In China, Tang Yuegang, Wang Shaoqing, Wang Xiaoshuai, Guo Xin, Wang Yafeng, Xue Liping, Harold H. Schobert

Coal Geology & Exploration

Objective The exploration and assessment of low-carbon, zero-emission, and maximized utilization of coal resources, emerge as a focus of coal geology in the 21st century. [Research Advances] Based on the research content of coals and coal geology, along with the domestic and international development trends of clean coal technology (CCT), this study defines clean coal geology in the broad and narrow sense. Clean coal geology in the narrow sense focuses on the geological and geochemical issues related to efficiency enhancement and emission reduction in coal processing and utilization. In contrast, clean coal geology in the broad sense emphasizes …

Wind And Topography Underlie Correlation Between Seasonal Snowpack, Mountain Glaciers, And Late-Summer Streamflow, Elijah N. Boardman, Andrew G. Fountain, Joseph W. Boardman, Thomas H. Painter, Evan W. Burgess, Laura Wilson, Adrian A. Harpold

Geology Faculty Publications and Presentations

In a warming climate, net mass loss from perennial snow and ice (PSI) contributes a temporary source of unsustainable streamflow. However, the role of topography and wind in mediating the streamflow patterns of deglaciating watersheds is unknown. We conduct lidar surveys of seasonal snow and PSI elevation change for five adjacent watersheds in the Wind River Range, Wyoming (WRR). Between 2019 and 2023, net mass loss from PSI is equivalent to ~10-36% of August-September streamflow. Across 338 manually classified PSI features >0.01 km2, glaciers contribute 68% of the total mass loss, perennial snowfields contribute 8%, rock glaciers contribute 1%, buried …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Advances And Trends Of Modern And Contemporary Research On The Geology Of Coal-Measure Minerals In China, Qin Yong

Coal Geology & Exploration

Background Coal-measure minerals (CMMs) play a significant role in ensuring the safe supply of mineral resources in China. Reviewing the advances and trends of research on the geology of CMMs in China holds great historical significance and practical value while potentially providing some insights into subsequent research. Advances Based on textual research and the analysis of logical relations, this study generalized the advances in research on the geology of CMMs in China into four aspects. (1) Increasingly improved geological theory system of CMMs: China’s classic theoretical system of coal field geology was formed in the second half of the 20th …

Gas Drainage And Utilization In Coal Mines In China: History, Technological Advances, And Prospects, Li Guofu, Li Chao, Zhang Bichuan, Xu Yun, Wang Zheng, Zhou Xianjun

Coal Geology & Exploration

Objective and Methods To promote the research and application of gas drainage and utilization technologies for coal mines, this study systematically summarizes the history of China’s coal mines transitioning from gas pumping to gas drainage, the accurate and effective gas drainage technologies for typical coal mining areas in China, and the latest applications of technologies related to safe gas gathering and transportation, as well as the utilization of gas with a full range of concentrations. This study aims to provide a reference for accelerating the advancement in gas drainage and utilization technologies for coal mines, achieving methane emission reduction, and …

Key Experimental Technologies And Their Development Directions For The Exploration And Production Of Deep Coalbed Methane, Yan Xia, Xu Fengyin, Xiong Xianyue, Wang Feng, Li Chunhu, Zhang Jiyuan, Xu Borui, Cheng Qianhui, Hu Xiong, Zhu Xueguang, Liang Wei, Yuan Pu, Feng Yanqing, Wei Zhenji

Coal Geology & Exploration

Objective Deep coalbed methane (CBM) production enjoys advantages including rapid gas shows, high single-well yield, and continuous resource distribution, which establish deep CBM as a significant target for reserve growth and production addition of natural gas. However, the exploration and production of deep CBM are still confronted with many technical challenges, and there is a lack of studies on key experimental technologies related to the geological characteristics and engineering assessment of deep CBM reservoirs, the occurrence characteristics and production mechanisms of gas and water, the formulation of production systems, and methods for enhanced CBM recovery. Advances in Research Given the …

Spatiotemporal Evolutionary Patterns Of The Hydrochemistry Of Jurassic Conglomerate Aquifers Under The Influence Of Curtain Walls, Chen Luwang, Wu Minghui, Hou Xiaowei, Hu Yongsheng, Zhang Miao, Cai Xinyue, Yin Xiaoxi, Shi Xiaoping

Coal Geology & Exploration

Objective Curtain walls, recognized as a primary project for the prevention and control of water disasters in coal mines, will change the dynamic field of groundwater. Furthermore, their dissolution will affect the chemical field of groundwater, leading to variations in its hydrochemical composition. Methods This study investigated the Jurassic conglomerate aquifers in the Zhuxianzhuang Coal Mine, Huaibei coal field. Based on the statistics of conventional hydrochemical composition, Piper diagrams, ion combination proportions, and principal component analysis (PCA), this study explored the impacts of curtain walls on the hydrochemistry of the aquifers and determined the spatiotemporal hydrochemical evolutionary patterns under the …