Earth Sciences Commons^™

Determining Pasture Biodiversity With Nirs, K. J. Moore, D. J. Barker

IGC Proceedings (1997-2023)

Research was conducted to assess the potential of using near infrared reflectance spectroscopy (NIRS) to determine botanical composition and measures of species diversity in pasture samples. Samples were collected from six hill country (Ballantrae) and two lowland (Aorangi) pastures in New Zealand. Samples were collected in summer (March) and Autumn (May) and subsamples were dissected to determine botanical composition and species diversity. Measures of diversity included species richness, Shannon’s index, and Simpson’s index. Reflectance data were collected from a second subsample that had been dried and finely ground. Calibrations were developed using modified partial least squares. Acceptable calibration equations were …

Vegetation Changes In Southeast Australian Temperate Grasslands, D. L. Garden, T. P. Bolger

IGC Proceedings (1997-2023)

In temperate areas of southeast Australia, the combined effects of tree clearing, grazing, application of fertilizer and the introduction of exotic species have modified the original grasslands. This paper describes these changes and attempts to explain them in terms of ecological principles derived from North American grasslands. Stability of the original grasslands appears to have been due to the lack of disturbance and the slow rates of nitrogen (N) cycling within them. Increased N cycling after disturbance has allowed invasion of species better adapted to higher N status, particularly exotic annual grasses and weeds. The present composition of grasslands, in …

The Effects Of Grazing Management And Fertilization On Grassland Diversity And Productivity, Warren Mcg. King, David R. Kemp

IGC Proceedings (1997-2023)

The effects of management practices on plant species diversity and productivity within a naturalised grassland was studied as part of a large-scale experiment designed to investigate issues of sustainability in temperate Australia. Fertiliser increased the production but reduced the diversity of the sward. The main decline was in exotic weed species. Strategic grazing resulted in a small increase in pasture diversity but a reduction in productivity. There was a consistent decline in diversity as productivity increased, across all treatments.

Pasture Dynamics After Sodseeding Cool Season Species With Or Without Glyphosate In Subtropical Natural Grasslands, Luciana M. Rizo, E. L. Moojen, Fernando L. F. De Quadros, F. E. Schlick, F. L. Correa

IGC Proceedings (1997-2023)

This trial was conducted to evaluate vegetation dynamics of natural grasslands fertilized and sodseeded with the cool season species Italian ryegrass (Lolium multiflorum), white clover (Trifolium repens) and birdsfoot trefoil (Lotus corniculatus) with or without glyphosate. Treatments that included herbicide spraying on natural vegetation caused a substitution of perennial grasses by undesirable species, and did not show a significant contribution of introduced species. Andropogon lateralis, Paspalum notatum, Paspalum dilatatum and Paspalum plicatulum almost disappeared, and were replaced by Chaptalia nutans and Apium spp, among others.

Soil Biodiversity, Root Herbivory And Carbon And Nitrogen Cycling In Grassland Soils, R. Cook, L. A. Dawson, A. C. Gange, S. J. Grayston, P. J. Murray, A. M. Treonis

IGC Proceedings (1997-2023)

This paper describes research on the relationships between grassland management practices and the diversity of biological communities in soil. Observations are being made in field trials with applications of nitrogen and lime and of insecticide to an original diverse sward and to a single species grass re-seed. The treatments are designed to produce different degrees of diversity in communities of soil animals and microbes. Assessments are being made over three years of the effects on the populations, activity and diversity of root-feeding animals, arbuscular mycorrhizal fungi, soil bacteria, fungi and micro fauna, including nonplant feeding nematodes. Associated laboratory experiments assess …

Core Collection Approaches And Genetic Diversity In Flemingia Macrophylla, R. Schultze‐Kraft, M. Peters

IGC Proceedings (1997-2023)

Core collections are a useful means to optimise the management, including conservation, of forage germplasm collections. Such optimisation is warranted in view of increasingly limited research resources. As there are several potential options to create core collections, a project is presented in which three approaches are compared: (i) based on germplasm origin information; (ii) genetic diversity assessment by agronomic characterisation/evaluation; and (iii) DNA markers. As example-species for the project, the tropical legume shrub Flemingia macrophylla is selected because of its particular multiple-use potential in smallholder production systems. An important diversity descriptor is the content of tannins influencing feed and litter …

Variation Of Agronomic Traits In A World Collection Of Vetch (Vicia Sativa L.), G. Pacucci, C. Troccoli

IGC Proceedings (1997-2023)

More than 850 accessions of vetch (Vicia sativa L.) representing 16 countries were obtained from the Italian Germplasm Institute and grown in a Southern Italy environment. The five following quantitative characters were analysed: days to harvest, plant dry weight, number of pods per plant, seed yield per plant, and seed yield per pod. The frequencies of various phenotypes were examined for total world collection and for each country in which there was a sufficient number of accessions. Wide phenotypic variability was observed for all characters, and usually within each country. The Shannon–Weaver diversity index (H') was used to examine …

Imaging The Tectonic Components Under The Eastern Mediterranean And Black Sea With Gravity (Satellite) Data, Ceyhan Ertan Toker, Emin U. Ulugergerli̇

Bulletin of the Mineral Research and Exploration

Tectonic structures in the Black Sea and the Levantine Sea were mapped using satellite gravity data. The relationship between Antalya and Cyprus arcs is revealed by the deformation traces of the arc formation. The Cyprus arc which over the slice that disappears from the South of the Anaximander seamounts to the Northeast, can traceable at the western end of the Antalya Bay. The distinction of western and eastern basins in the Black Sea is also mapped. Due to the low spatial resolution, additional studies with higher resolution are required.

https://doi.org/10.19111/bulletinofmre.975929

Geological Characteristics And Reservoir-Forming Potential Of Shale Gas Of Transitional Facies In Linxing Area, Eastern Margin Of Ordos Basin, Wu Peng, Cao Di, Zhu Guanghui, Liu Xueqing, Li Yong, Li Yangbing, Hu Weiqiang, Liu Zaizhen, Kong Wei, Fei Jingliang

Coal Geology & Exploration

Shale gas of transitional facies is the important replacing area for increase of shale gas reserves and production. On the basis of the experiment and research data of shale of transitional facies of Linxing area in the eastern margin of Ordos Basin, by selecting the strata series of Shanxi Formation, Taiyuan Formation and Benxi Formation as the research object, from the sedimentary environments, shale distribution, organic geochemical characteristics, mineralogy, physical characteristics and gas-bearing characteristics, etc., the geology characteristics of the shale gas transitional facies in the study area were summarized and dissected systematically to analyze its enrichment and reservoir-forming potential. …

Prediction Of Fracture Distribution And Evaluation Of Shale Gas Preservation Conditions In Longmaxi Formation In Dongxi Area, Xie Jiatong, Fu Xiaoping, Qin Qirong, Li Hu

Coal Geology & Exploration

Commercial development of shale gas confirmed that mature shale has great potential for exploration, southeast Sichuan is the strategic pilot area of shale gas exploration and development in southern China, cracks are the key factor of shale gas preservation and development deployment, for the structural environment complex and special basin edge area, increasing the difficulty of shale crack research, but also provides a new direction for shale gas exploration and development. As a new field of oil and gas exploration in China, shale gas exploration has not yet developed a mature crack evaluation system. Taking Dongxi area of the southeast …

Characteristics Of Shallow Coal Measure Gas Reservoir And Key Technologies Of Exploration And Development In Yaojie Mining Area, Du Xinfeng, Yuan Chongliang, Wang Zhengxi, Wang Junde, Li Shibing, Liu Jingdan, He Xiuqing, Zhang Tianguo, Shan Yuanwei, Fang Jiawei

Coal Geology & Exploration

The exploration and development of coal measures gas can not only effectively improve the single well production of coalbed methane in coal mining areas, reduce the waste of resources, but also alleviate the energy crisis in China, reduce coal mine gas accidents, protect the atmospheric environment, and contribute to the realization of carbon peak and carbon neutralization. Based on the shallow coal measure gas development demonstration project in the third mining area of Haishiwan mine field, the characteristics of coal measure gas reservoirs in Yaojie mining area are analyzed, and the key technologies for coal-measure gas exploration and development are …

A 3d Seismic Physical Modeling System Of Large Double Triaxial Air-Supported Positioning And Multichannel Data Acquisition And Its Application, Shi Xianxin, Liu Qiang, Hu Jiwu, Wang Pan, Lian Chenguang, Jia Qian, Zhang Miaomiao, Nie Ailan

Coal Geology & Exploration

As an important technology to study seismic wave propagation characteristics, 3D seismic physical simulation is an effective method to understand the propagation law and response characteristics of seismic waves in complex structures. It has the advantages of more realistic results and no limitation on calculation methods and boundary conditions over numerical simulation. Therefore, it has important applications in the research of the basic law of seismic wave propagation, verification of field seismic exploration methods, design optimization of observation systems, etc. This paper presents a 3D seismic physical modeling system of large double triaxial air-supported positioning and multichannel data acquisition, which …

Physical Modeling Of Seismic Response For The Coal Seams Of Yan'an Formation In Loess Tableland Of North China, Xing Tingdong, Xue Shigui, Li Xiaowei, Suo Chonghui, Wang Huiming, Jiao Yanyan

Coal Geology & Exploration

A seismic physical simulation is carried out for the complex seismic response of the coal seam of Yan'an Formation in the loess tableland. First, the physical model materials for the dry layer near the surface of the loess tableland and the coal seam are developed. After several tests, a mixture of silicone rubber with silicon aerogel powder is selected to simulate the surface of the loess tableland, and the mixture with ultra-fine carbon powder added to silicone rubber is used to simulate the low-speed and low-density coal seam. Through the methods of molds control layer, layer by layer pouring, three-dimensional …

Discussion On The Recommended Models For Resource Reuse Of Closed Coal Mines In Main Mining Areas Of Hebei Province, Yin Quanzeng, Chen Zhongshan, Feng Qiyan, Geng Lijuan, Lian Lixun, Li Fang, Liu Ning

Coal Geology & Exploration

The evaluation and the utilization of the resources of the closed coal mines have dual benefits of resources and environment, and can provide a transformation and development path for coal mining enterprises. Based on the investigation of the resources of the closed coal mines in the main mining areas of Hebei Province, through the summary of the typical cases of the resources reuse of the closed coal mines at home and abroad and in Hebei Province, this paper sums up 7 types and 19 kinds of recommended modes of the resources reuse of the closed coal mines in Hebei Province, …

Plastic Deformation-Based Constitutive Relation Of Coal Damage And Permeability Model, Wu Xuehai, Li Bobo, Wang Xin, Gao Zheng, Li Jianhua, Xu Jiang

Coal Geology & Exploration

Coal and gas outburst induced by mining disturbance is one of the main gas dynamic disasters in coal mine production. In order to systematically explore the evolution characteristics of coal damage and the law of gas seepage under mining disturbance, the whole stress strain–seepage experiment under different gas pressures was carried out. The generalized Hooke's law was modified by considering the effects of gas adsorption and thermal expansion, the plastic deformation-based constitutive relation of coal damage was established, and the piecewise permeability model considering the damage was further constructed. The results shown that the coal permeability can be divided into …

Saxs-Based Nano-Scale Pore Structure Characteristics Of Coals With Different Metamorphic Degrees, Zhang Yu, Li Yong, Wang Yanbin, Wang Zhuangsen, Zhao Shihu, Han Wenlong

Coal Geology & Exploration

In order to reveal the characteristics of nano-scale pores in coals with different metamorphic degrees, the small-angle X-ray scattering method (SAXS) is used to obtain the porosity, pore size distribution, specific surface area and fractal dimension of 15 samples whose vitrinite reflectance R_max is 0.31%-6.24%, and the low temperature CO₂ and N₂ adsorption DFT model results are used to verify the pore size distribution. The results show: during coalification process, when R_max is < 0.5%, the porosity and the specific surface area of coal increase with the increase of metamorphic degree, the micropores(< 2 nm) content increases seldomly, the mesoporous(2-50 nm) and microporous(50-100 nm) content increase greatly, and the surface of coal is gradually smooth. When R_max=0.5%-1.4%, the porosity and the specific surface area decrease, and each type of pore content is reduced, and the surface of …

Prevention And Control Technology Of Goaf Water Hazard In Unauthorized Mining Areas Of Extremely Soft And Medium-Thick Coal Seams, Li Zhi, Zheng Shitian, Shi Zhiyuan, Wang Yuhang

Coal Geology & Exploration

Unauthorized mining in coal pit is common in China's coal industry. As the scope of unauthorized mining and the amount of accumulated water are hard to determine, the goaf water seriously threatens the safety of mining in adjacent large coal mines. In order to explore the unauthorized boundary of coalpits quickly and accurately and prevent the threat of goaf water, the long distance drilling technology of ground bedding borehole in medium and thick coal seam is proposed based on the controllable trajectory and accurate positioning of ground directional drilling, which mainly includes precise drilling in extremely soft and medium-thick coal …

Study On The Microscopic Mechanism Of The Loess Improved By Quicklime, Xie Xiao, Wang Luyao, Deng Lejuan, Zhang Guowei

Coal Geology & Exploration

To investigate the influence of lime content on loess strength and its microscopic mechanism, different proportions of lime were used to improve loess. Through direct shear test, mercury intrusion porosimetry and scanning electron microscopy, the strength characteristics and microstructure changes of compacted loess and modified loess with different lime contents were analyzed qualitatively and quantitatively, and the microscopic mechanism of lime-improved loess was analyzed in depth. The results show that the shear strength parameters of lime-improved loess increases first and then decreases with the increase of lime contents. The cohesive force and internal friction angle reach the maximum when the …

Application Of Unmanned Aerial Vehicle In Surface Soil Characterization And Geological Disaster Monitoring In Mining Areas, Long Linli, Liu Ying, Zhang Xuyang, Su Yongdong, Chen Xiaoyang

Coal Geology & Exploration

With the emergence and development of UAVs and the improvement of the miniaturization and intelligence of various sensor, UAVs equipped with sensors have become an efficient tool for obtaining spatial data. Because UAVs are low cost, short revisit period, fast and efficient, light and flexible, simple operation, and high temporal and spatial accuracy of image acquisition, it is widely used in mining land damage monitoring. Using "UAV, Inversion, Soil Monitoring, Surface Collapse, Ground Fissure" as keywords, this paper summarizes the academic papers of the search system in the web of science, CNKI, and Google Scholar from January 2010 to May …

The Development Law Of Surface Cracks In Shallow Coal Seam Mining Through Double Gullies Terrain, Sun Xueyang, Zhang Huixuan, Lu Mingjiao, Li Cheng, Miao Lintian

Coal Geology & Exploration

In order to protect the ecological environment of the mining area in the Yellow River Basin, the mining-induced surface crack development law was summarized from the parameters of surface crack development location and development morphology during mining of the working face passing through the double gullies terrain by using a combination of numerical simulation experiments, similar material simulation experiments and theoretical analysis in the context of the working face 125203 of Anshan Coal Mine in Miaohagu Mining Area of Fugu County. Through theoretical analysis, the relative position function T of surface cracks in shallow coal seam mining through double gullies …