惠安堡-马家滩地区二叠系煤系烃源岩

综合运用有机岩石学、岩石热解分析及有机地球化学等方法,以井下暗色泥岩的分析资料为主,结合地表剖面暗色泥岩样品分析数据,研究和分析了鄂尔多斯西缘惠安堡—马家滩地区二叠系煤系烃源岩的有机质生烃特征、煤系烃源岩的沉积环境。研究表明:太原组、山西组煤系暗色泥岩为二叠系主要的烃源岩层系;有机质类型以Ⅲ型为主。二叠系煤系烃源岩已不同程度进入成熟—高成熟—过成熟阶段。     

The sustainable use and conservation of biodiversity in ABNJ: What can be achieved using existing international agreements?

While the international community debates the desirability and possible content of a new global instrument for the conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction, alternative approaches to improving the application and implementation of existing agreements for the protection of biodiversity appear to have fallen off the agenda. Recent practice under existing global and regional agreements suggests that, given political will, significantly greater protections could be achieved through the more effective implementation of individual sectoral agreements. However, while single-sector measures have the potential to make a valuable contribution, ultimately only multi-sectoral, integrated, cooperative management can ensure the conservation and long-term sustainable use of marine biodiversity in ABNJ. This requires establishing mechanisms for cooperation both intra and inter-sectorally, as well as between the sectoral and global and regional conservation agreements. This paper examines recent initiatives within various sectoral and conservation treaty regimes aimed at improving their application within ABNJ as well as some of the challenges to, and options for, further and better cooperation and coordination among and between existing regimes, and it identifies a range of possible mechanisms for achieving more effective implementation and coordination among them. Greater use of existing mechanisms represents a sensible approach to making the most of existing arrangements without in any way foreclosing the possibility of the adoption of a more comprehensive, integrated global agreement for the protection of marine biodiversity in ABNJ.     

A comparison of techniques for generating forest ownership spatial products

To fully understand forest resources, it is imperative to understand the social context in which the forests exist. A pivotal part of that context is the forest ownership. It is the owners, operating within biophysical and social constraints, who ultimately decide if the land will remain forested, how the resources will be used, and by whom. Forest ownership patterns vary substantially across the United States. These distributions are traditionally represented with tabular statistics that fail to capture the spatial patterns of ownership. Existing spatial products are not sufficient for many strategic-level planning needs because they are not electronically available for large areas (e.g., parcels maps) or do not provide detailed ownership categories (e.g., only depict private versus public ownership). Thiessen polygon, multinomial logit, and classification tree methods were tested for producing a forest ownership spatial dataset across four states with divergent ownership patterns: Alabama, Arizona, Michigan, and Oregon. Over 17,000 sample points with classified forest ownership, collected as part of the USDA Forest Service, Forest Inventory and Analysis (FIA) program, were divided into two datasets, one used as the dependent variable across all of the models and 10 percent of the points were retained for validation across the models. Additional model inputs included a polygon coverage of public lands from the Conservation Biology Institute’s Protected Areas Database (PAD) and data representing human population pressures, road densities, forest characteristics, land cover, and other attributes. The Thiessen polygon approach predicted ownership patterns based on proximity to the sample points in the model dataset and subsequent combining with the PAD ownership data layer. The multinomial logit and classification tree approaches predicted the ownership at the validation points based on the PAD ownership information and data representing human population, road, forest, land cover, and other attributes. The percentage of validation points across the four states correctly predicted ranged from 76.3 to 78.9 among the methods with corresponding weighted kappa values ranging from 0.73 to 0.76. Different methods performed slightly, but statistically significantly, better in different states Overall, the Thiessen polygon method was deemed preferable because: it has a lower bias towards dominant ownership categories; requires fewer inputs; and is simpler to implement.     

贵州喀斯特区草地生态条件下石灰(岩)土的发生特性及系统分类研究

选取贵州喀斯特区草地生态条件下5个不同区域的石灰(岩)土为研究对象,根据相应的理化性质及发生特性,探讨了影响土壤发育的因素,确定了土壤的诊断层和诊断特性。其中,供试土壤的诊断层包括:暗沃表层、雏形层和粘化层等,诊断特性包括:热性土壤温度状况、常湿润土壤水分状况、均腐殖质特性、腐殖质特性、盐基饱和、碳酸盐岩岩性、铁质特性、石灰性等,并在此基础上对其进行了土壤系统分类,结果显示:5个供试土壤分别属于中国土壤系统分类中的普通黑色岩性均腐土、腐殖钙质常湿雏形土和腐殖钙质常湿淋溶土等亚类。      

The long-term impacts of fisheries on epifaunal assemblage function and structure, in a Special Area of Conservation

Fisheries can have profound effects on epifaunal community function and structure. We analysed the results from five dive surveys (1975-1976, 1980, 1983, 2003 and 2007), taken in a Special Area of Conservation, Strangford Lough, Northern Ireland before and after a ten year period of increased trawling activity between 1985 and 1995. There were no detectable differences in the species richness or taxonomic distinctiveness before (1975-1983) and after (2003-2007) this period. However, there was a shift in the epifaunal assemblage between the surveys in 1975-1983 and 2003-2007. In general, the slow-moving, or sessile, erect, filter-feeders were replaced by highly mobile, swimming, scavengers and predators. There were declines in the frequency of the fished bivalve Aequipecten opercularis and the non-fished bivalves Modiolus modiolus and Chlamys varia and some erect sessile invertebrates between the surveys in 1975-1983 and 2003-2007. In contrast, there were increases in the frequency of the fished and reseeded bivalves Pecten maximus and Ostrea edulis, the fished crabs Cancer pagurus and Necora puber and the non-fished sea stars Asterias rubens, Crossaster papposus and Henricia oculata between the surveys in 1975-1983 and 2003-2007. We suggest that these shifts could be directly and indirectly attributed to the long-term impacts of trawl fishing gear, although increases in the supply of discarded bait and influxes of sediment may also have contributed to changes in the frequency of some taxa. These results suggest that despite their limitations, historical surveys and repeat sampling over long periods can help to elucidate the inferred patterns in the epifaunal community. The use of commercial fishing gear was banned from two areas in Strangford Lough in 2011, making it a model ecosystem for assessing the long-term recovery of the epifaunal community from the impacts of mobile and pot fishing gear.     

Over 10 years of variation in Mediterranean reef benthic communities

During the last several decades, the Mediterranean littoral shallow water benthic communities have suffered significant changes in their structure and taxa composition. Despite numerous studies conducted to characterize these changes at various levels, it has always been very difficult to disentangle the effects of natural factors from anthropic ones. The main purpose of this work was to evaluate possible changes, over a 10‐year scale, in diversity and abundance of the most representative species of the benthic communities considered to be primarily and potentially affected by natural stressors in a highly protected area. Sets of macro‐photographs were taken in 2002–2003 of three sites inside a small bay called Ca’ dell'Oro, which is the “no entry—no take” zone of the Marine Protected Area of Portofino, in order to analyse the structure of the benthic communities at different depths over a short time scale. The same sampling was repeated 10 years later in 2013. In the 10‐year span, a significant change in the macroalgal coverage and composition was observed, while the overall richness and coverage of species remained almost unchanged. This process resulted in a significant reduction of the habitat complexity of the three‐dimensional algal components. Likewise, a remarkable change in terms of presence and abundance occurred among all zoobenthic components. The benthic communities seem to have suffered from detrimental effects probably caused by climatic events that have been occurring in recent years in the Ligurian Sea.     

黄河流域三维地形飞行模型开发的技术流程与方法

三维可视化技术为人们描述现实中的三维世界提供了很大的方便和可能性。本文阐述了运用PCI、ArcGIS8.0及多媒体技术建立黄河流域三维飞行虚拟场景的构造方法以及飞行浏览的全过程。     

豫西杜家沟铝土矿中镓的分布规律及控制因素浅析

镓是一种价格昂贵的稀贵金属，它的回收利用问题逐渐引起人们的重视。在对杜家沟铝土矿床矿石中镓的分布特征做了多方面对比研究的基础上，归纳出镓的分布规律：空间上、镓在不同层位的矿石中平均含量变化显著，镓含量随着矿层平均厚度的增大而增大。遭受强烈的表生富集作用，铝土矿中镓的平均品位较高。从矿石结构类型来看，蜂窝状矿石中的镓品位明显高于豆、鲕状和致密状矿石。另外，另外，矿石中镓的含量总与富矿体关系密切。     

江苏省宁镇扬山地丘陵地区农业资源的综合开发利用

宁镇扬山地丘陵地区土地面积133.9万公顷,农业资源丰富,是江苏省开发潜力很大的地区之一。本文从气候资源、水资源、土地资源和生物资源,阐述了它们的区域优势;探讨了农业资源开发利用中的主要问题。提出了综合开发利用的建议和对策,制定农业资源综合开发的总体规划;建立农业资源综合开发治理试验区;发挥山丘地区资源优势,建立商品生产基地。     

The Demographic Constraints on Future Population Growth in Regional Australia

Concern about rapid population growth in Australia's large cities and slower growth in many non-metropolitan areas has stimulated a range of government policies attempting to lift non-metropolitan growth rates. However, there is relatively little research on which to base these policies. It would be helpful to understand more about the consequences of current demographic trends continuing and the effects of alternative migration patterns. This paper presents sub-national population projections for Australia over the horizon 2011–2041, basing the projections on more socially meaningful Remoteness Areas instead of common statistical geographies. Three sets of projections were generated: a Current Direction scenario in which recent demographic trends are maintained, a Regional Immigration scenario in which more immigrants settle in regional and remote areas, and a Metro Exodus scenario in which there is increased internal migration from metropolitan to non-metropolitan areas. The future of Australia's population geography is shown to be one of spatially varying growth and population ageing, and continued metropolitanisation. In regional areas rapid population ageing will lower natural increase rates and thus reduce overall growth, resulting in a falling share of the national population. Policy measures attempting to increase the share of growth in regional areas will struggle against natural demographic forces operating in the opposite direction.