Knowledge gathering and communication on biodiversity: Developing the Norwegian Nature Index     

《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(5):300-308

The authors reflect on knowledge-generating and communication processes involved in the recently developed Norwegian Nature Index, particularly the communication process among experts involved in providing the required biodiversity knowledge. Eliciting a comprehensive overview of biodiversity is a complex process involving choices of approaches and methods in order to reach a common understanding of uncertainties and values as a basis for quantification. Part of the complexity is the establishment of dialogue between experts from research institutions with different research traditions and approaches. The authors discuss how the index was developed through communication processes, challenging involved experts to provide not only biodiversity data for the current situation, but also forecasts of future trends, assessments of uncertainty, and evaluations of the urgency of biodiversity loss and possibility of implementing policy and management measures. The Nature Index framework has potential for informing the biodiversity policy debate by involving stakeholders beyond the science-policy community and enhancing deliberations about biodiversity policy in a wider context of sustainable development. As a policy tool, the Nature Index may develop through a process of practical application, which in turn may have an impact on the selection of narratives, definition of management targets, and technical concepts such as reference states.  相似文献   

近30年羌塘自然保护区气候特征分析   总被引：1，自引：0，他引：1  

李林  杨秀海  扎西央宗  巴桑顿珠 《四川气象》2010,(1):62-65

本文利用羌塘自然保护区周边6个气象站1978～2007年30年数据,利用气候统计方法,分析了温度、积温、降水的趋势变化。结果表明：该地区年平均温度、年平均最高温度、年平均最低温度都呈上升趋势,且上升幅度远远大于全球、全国平均水平;≥0℃积温、≥5℃积温呈增加趋势,初日提前,终日推迟,持续日数增加;降水的区域特征明显,自东向西呈递减趋势。年降水量呈上升趋势。  相似文献   

The Proterozoic,albitite-hosted,Valhalla uranium deposit,Queensland, Australia: a description of the alteration assemblage associated with uranium mineralisation in diamond drill hole V39     

Paul A. Polito  T. Kurt Kyser  Cliff Stanley 《Mineralium Deposita》2009,44(1):11-40

The Valhalla uranium deposit, located 40 km north of Mount Isa, Queensland, Australia, is an albitite-hosted, Mesoproterozoic U deposit similar to albitite-hosted uranium deposits in the Ukraine, Sweden, Brazil and Guyana. Uranium mineralisation is hosted by a thick package of interbedded fine-grained sandstones, arkoses and gritty siltstones that are bound by metabasalts belonging to the ca. 1,780 Ma Eastern Creek Volcanics in the Western Succession of the Mount Isa basin. Alteration associated with U mineralisation can be divided into an early, main and late stage. The early stage is dominated by laminated and intensely altered rock comprising albite, reibeckite, calcite, (titano)magnetite ± brannerite. The main stage of mineralisation is dominated by brecciated and intensely altered rocks that comprise laminated and intensely altered rock cemented by brannerite, apatite, (uranoan)-zircon, uraninite, anatase, albite, reibeckite, calcite and hematite. The late stage of mineralisation comprises uraninite, red hematite, dolomite, calcite, chlorite, quartz and Pb-, Fe-, Cu-sulfides. Brannerite has U–Pb and Pb–Pb ages that indicate formation between 1,555 and 1,510 Ma, with significant Pb loss evident at ca. 1,200 Ma, coincident with the assemblage of Rodinia. The oldest ages of the brannerite overlap with ⁴⁰Ar/³⁹Ar ages of 1,533 ± 9 Ma and 1,551 ± 7 Ma from early and main-stage reibeckite and are interpreted to represent the timing of formation of the deposit. These ages coincide with the timing of peak metamorphism in the Mount Isa area during the Isan Orogeny. Lithogeochemical assessment of whole rock data that includes mineralised and unmineralised samples from the greater Mount Isa district reveals that mineralisation involved the removal of K, Ba and Si and the addition of Na, Ca, U, V, Zr, P, Sr, F and Y. U/Th ratios indicate that the ore-forming fluid was oxidised, whereas the crystal chemistry of apatite and reibeckite within the ore zone suggests that F⁻ and were important ore-transporting complexes. δ¹⁸O values of co-existing calcite and reibeckite indicate that mineralisation occurred between 340 and 380°C and involved a fluid having δ¹⁸O_fluid values between 6.5 and 8.6‰. Reibeckite δD values reveal that the ore fluid had a δD_fluid value between −98 and −54‰. The mineral assemblages associated with early and main stages of alteration, plus δ¹⁸O_fluid and δD_fluid values, and timing of the U mineralisation are all very similar to those associated with Na–Ca alteration in the Eastern Succession of the Mount Isa basin, where a magmatic fluid is favoured for this style of alteration. However, isotopic data from Valhalla is also consistent with that from the nearby Mount Isa Cu deposit where a basinal brine is proposed for the transport of metals to the deposit. Based on the evidence to hand, the source fluids could have been derived from either or both the metasediments that underlie the Eastern Creek Volcanics or magmatism that is manifest in the Mount Isa area as small pegmatite dykes that intruded during the Isan Orogeny.  相似文献   

MATLAB 平台下基于克立格理论的固体资源储量估算 系统的开发与实践     

陈聆 《地质与勘探》2009,45(3):287-291

文章以MATLAB技术为平台,以西藏自治区雄村铜矿床为实例,详细讨论了如何开发以克立格理论为基础的固体资源储量估算系统,其中包括模块:数据预处理、变异函数分析、克立格估值、储量估算、地质可靠度评价等.论文使用该系统对西藏自治区雄村铜矿床进行储量预测,得出结果数据表格;并对原生矿体、次生矿体、氧化矿体、总矿体、矿体的自然形态以及在工业品位规范下的矿体形态进行拟合.通过与专业储量估算软件Minesjght的估算结果对比,证明了本系统的可靠性和实用性.  相似文献   

1990-2019年贡嘎山地区典型冰川表碛覆盖变化及其空间差异     

廖海军  刘巧  钟妍  鲁旭阳 《地理学报》2021,76(11):2647-2659

表碛覆盖型冰川是中国西部较为常见的冰川类型。表碛层存在于大气—冰川冰界面,强烈影响大气圈与冰冻圈之间的热交换。表碛厚度的空间异质性可极大地改变冰川的消融率和物质平衡过程,进而影响冰川径流过程和下游水资源。基于Landsat TM/TIRS数据,运用能量平衡方程反演了贡嘎山地区冰川表碛厚度,研究了贡嘎山地区冰川在1990—2019年间表碛覆盖范围及厚度变化情况,同时对比了东西坡差异。结果表明：① 贡嘎山地区冰川表碛扩张总面积达43.824 km²。其中,海螺沟冰川扩张2.606 km²、磨子沟冰川1.959 km²、燕子沟冰川1.243 km²、大贡巴冰川0.896 km²、小贡巴冰川0.509 km²、南门关沟冰川2.264 km²,年均扩张率分别为3.2%、11.1%、1.5%、0.9%、1.0%和6.5%;② 海螺沟冰川、磨子沟冰川、燕子沟冰川、大贡巴冰川、小贡巴冰川、南门关沟冰川表碛平均增厚分别为5.2 cm、3.1 cm、3.7 cm、6.8 cm、7.3 cm和13.1 cm;③ 西坡冰川表碛覆盖度高,表碛覆盖年均扩张率低,冰川末端退缩量小;东坡冰川表碛覆盖年均扩张率高,但表碛覆盖度总体低于西坡,冰川末端退缩量大。  相似文献   

An assessment of land cover change as a source of information for conservation planning in the Vhembe Biosphere Reserve     

《Applied geography (Sevenoaks, England)》2017

Determining changes in land use/land cover (LULCC) can be used to assess and monitor habitat loss as one of the five global priority causes of biodiversity loss. In South Africa, two national land-cover (NLC) datasets have been developed from satellite imagery obtained in circa 1990 and 2013/2014. The Vhembe Biosphere Reserve (VBR), designated in 2009, is located in the north of the Limpopo Province in South Africa and has a surface area of 30,457 km². The aim of biosphere reserves is to provide a landscape-scale framework for conservation and sustainable development of an area. The area within a biosphere reserve is prioritised by designating it into one of three zones 1) Core, 2) Buffer, and 3) Transitional Zones. Two national parks and six provincial reserves (PAs) are the current and form part of the proposed updated core areas (pCAs) of the VBR. Intensity analyses was used to assess LULCC in the VBR. The pCAs cover 39.7% of the surface area of the VBR. The PAs cover 39.7% and only 15.8% of the surface area of the pCAs and VBR respectively. Based on the NLC 2013/2014 a majority of the VBR, pCAs and PAs consisted of indigenous vegetation dominated by Woodland/Open bush, Grassland, and Thicket/Dense bush. The extent of transformed land in the VBR declined from 1990 to 2013 by 1697.7 km². The total amount of change and mean annual change in the VBR was 53.1% and 2.31% respectively. The overexploitation of fuel wood by rural communities in rural areas of the VBR, was partly responsible for the targeted loss of Woodland/Open bush to Thicket/Dense bush and Grasslands. The unquantified presence of novel vegetation and alien invasive plants means that the NLC 1990 and 2013/2014 overestimates the quantity and distribution of the remaining indigenous vegetation in the VBR. In order to address this the distribution of alien and indigenous invasive plant species in the VBR needs to be determined and used to update future NLCs. Assuming a worse-case-scenario of all the coal deposits in the VBR, including the Kruger National Park, being mined it would amount to 24.7% of the surface area of the VBR. Only 6.8% of the area of all the coal deposits in the VBR was transformed with 93.2% currently remaining untransformed. It is recommended that transformation of indigenous vegetation to one of the seven transformed land cover categories and more specifically from coal mining should be restricted to the VBR's Transition Zones.  相似文献   

基于HJ-1A高光谱影像的湿地精细分类     

张雅春  那晓东  臧淑英 《地理科学进展》2018,37(12):1705-1712

混合像元的存在不仅影响了基于高光谱影像的地物识别和分类精度,而且已成为遥感科学向定量化发展的主要障碍。本文以扎龙湿地为试验区,以环境一号卫星采集的高光谱影像为数据源,分别采用传统的全约束最小二乘光谱解混算法(fully constrained least squares spectral unmixing algorithm, FCLS)与基于稀疏约束最小二乘光谱解混算法(sparse constrained least squares spectral unmixing algorithm, SUFCLS)实现了试验区湿地的精细分类,并对两种分类结果的表现及其分类精度进行了对比分析。研究结果表明：SUFCLS算法能够自适应的从光谱库中选择场景中所占比例最高的一组端元,并将此端元的组合应用于传统的全约束最小二乘光谱解混中实现不同湿地类型丰度的提取,该算法充分考虑了端元的空间异质性,弥补了FCLS算法在端元选取过程中的不足。精度验证结果表明与FCLS算法相比,SUFCLS算法分类结果的均方根误差更小,丰度的相关系数更高,因此该方法对于提高湿地解混精度以及实现湿地精细化分类具有重要意义。  相似文献   

区域可持续发展的若干理论问题研究   总被引：21，自引：5，他引：16  

申玉铭  毛汉英 《地理科学进展》1999,18(4):287-295

区域可持续发展是一项涉及到自然、经济、社会三个子系统组成的动态、开放复杂系统, 其研究内容涉及到地理学、资源管理、生态学、环境科学、人口学、系统工程、经济学、社会学等许多相关领域。本文以人地关系地域系统理论为基础, 从区域与区域之间不同时空尺度的PRED相互联系、相互影响的制约关系出发, 分析了人地系统的特点、结构和功能,并探讨了人地关系优化的核心、区域可持续发展的理论模式以及可持续发展的系统调控等问题。  相似文献   

人地关系与脆弱带的研究   总被引：13，自引：2，他引：11  

孙武 《中国沙漠》1995,15(4):419-424

兴起于80年代后期的生态脆弱带研究,标志着"持续发展"的现代人地关系理论对人类生存环境哲学思考的深化。侧重于植物生态领域的脆弱带概念现已被拓宽,生态学、人口承载力、害灾学、荒漠化成为其四个主要的研究方面;由人地关系矛盾所决定的性质的不稳定性为脆弱带的主要特征;界面性、波动性、基质性是脆弱带的主要成因类型。  相似文献   

模拟天然气水合物的岩石物理特性模型实验   总被引：13，自引：1，他引：13       下载免费PDF全文

赵群  郭建  郝守玲  耿建华 《地球物理学报》2005,48(3):649-655

针对水合物沉积的悬浮、颗粒接触和胶结三种微观模式,制作一组微弱胶结非固结高孔隙度人造样品和颗粒填充渐变的三维物理模型. 通过物理模型实验研究天然气水合物物性参数的敏感性. 实验结果表明：在弱颗粒间胶结物和低有效应力的固结差的沉积物中,声波对孔隙流体性质较敏感. 随着温度的降低颗粒胶结,改变原有沉积物的岩石物理特性,速度、弹性模量和频率升高,声波衰减和Vp/VS减小,沉积层内的反射波消隐.  相似文献