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31.
Several international initiatives, including the European Biodiversity Strategy to 2020, promote the identification and mapping of ecosystems as basic tools for the conservation of biodiversity and related services. On coarse scales, the spatial representation of ecosystems is usually based on broad land cover categories that largely overlook important ecological and biogeographic features of the biotic communities they are meant to exemplify. This paper presents a nationwide ecosystem mapping approach that promotes a degree of thematic detail, which is more suited than that found in the continental maps to meeting biodiversity conservation targets in Italy. The approach is based on the rationale that current and potential vegetation cover are valuable proxies for outlining ecosystems. The resulting Ecosystem Map of Italy includes 43 types of forest ecosystems instead of the 5 woodland, forest and other wooded land types recognized at the European level. We outline the expected advantages of this enhanced thematic detail for a number of conservation purposes and highlight how the resulting maps may help to meet biodiversity conservation targets at the national level. In particular, we refer to the assessment of conservation status, the definition of restoration priorities, the planning of green infrastructure and the identification of collapse risks for the ecosystems identified. Comprehensively, the definition, characterization and assessment of ecosystem types represent the carrying structure of the recently launched national system of natural capital accounting.  相似文献   
32.
This article discusses some of the demonstrated and potential uses of data from satellites with large fields of view and high frequency of coverage, such as NOAA AVHRR data and Nimbus-7 CZCS data. The use of such data is discussed for three types of applications: (a) stratification, (b) change detection, and (c) area estimation. It is concluded that such data have considerable promise as an aid to a variety of large-area inventory and monitoring tasks.  相似文献   
33.
Objective: There has been a longstanding desire for a map to convert International Classification of Diseases (ICD) injury codes to Abbreviated Injury Scale (AIS) codes to reflect the severity of those diagnoses. The Association for the Advancement of Automotive Medicine (AAAM) was tasked by European Union representatives to create a categorical map classifying diagnoses codes as serious injury (Abbreviated Injury Scale [AIS] 3+), minor/moderate injury (AIS 1/2), or indeterminate. This study's objective was to map injury-related ICD-9-CM (clinical modification) and ICD-10-CM codes to these severity categories.

Methods: Approximately 19,000 ICD codes were mapped, including injuries from the following categories: amputations, blood vessel injury, burns, crushing injury, dislocations/sprains/strains, foreign body, fractures, internal organ, nerve/spinal cord injury, intracranial, laceration, open wounds, and superficial injury/contusion. Two parallel activities were completed to create the maps: (1) An in-person expert panel and (2) an electronic survey. The panel consisted of expert users of AIS and ICD from North America, the United Kingdom, and Australia. The panel met in person for 5 days, with follow-up virtual meetings to create and revise the maps. Additional qualitative data were documented to resolve potential discrepancies in mapping. The electronic survey was completed by 95 injury coding professionals from North America, Spain, Australia, and New Zealand over 12 weeks. ICD-to-AIS maps were created for: ICD-9-CM and ICD-10-CM. Both maps indicated whether the corresponding AIS 2005/Update 2008 severity score for each ICD code was AIS 3+, 1/2, or indeterminable. Though some ICD codes could be mapped to multiple AIS codes, the maximum severity of all potentially mapped injuries determined the final severity categorization.

Results: The in-person panel consisted of 13 experts, with 11 Certified AIS specialists (CAISS) with a median of 8 years and an average of 15 years of coding experience. Consensus was reached for AIS severity categorization for all injury-related ICD codes. There were 95 survey respondents, with a median of 8 years of injury coding experience. Approximately 15 survey responses were collected per ICD code. Results from the 2 activities were compared, and any discrepancies were resolved using additional qualitative and quantitative data from the in-person panel and survey results, respectively.

Conclusions: Robust maps of ICD-9-CM and ICD-10-CM injury codes to AIS severity categories (3+ versus <3) were successfully created from an in-person panel discussion and electronic survey. These maps provide a link between the common ICD diagnostic lexicons and the AIS severity coding system and are of value to injury researchers, public health scientists, and epidemiologists using large databases without available AIS coding.  相似文献   
34.
Evaluation of wetland extent and changes in extent is a foundation of many wetland monitoring and assessment programs. Probabilistic sampling and mapping provides a cost‐effective alternative to comprehensive mapping for large geographic areas. One unresolved challenge for probabilistic or design‐based approaches is how best to monitor both status (e.g., extent at a single point in time) and trends (e.g., changes in extent over time) within a single monitoring program. Existing wetland status and trends (S&T) monitoring programs employ fixed sampling locations; however, theoretical evaluation and limited implementation in other landscape monitoring areas suggest that alternative designs could increase statistical efficiency and overall accuracy. In particular, designs that employ both fixed and nonfixed sampling locations (alternately termed permanent and temporary samples), termed sampling with partial replacement (SPR), are considered to efficiently and effectively balance monitoring current status with detection of trends. This study utilized simulated sampling to assess the performance of fixed sampling locations, SPR, and strictly nonfixed designs for monitoring wetland S&T over time. Modeled changes in wetland density over time were used as inputs for sampling simulations. In contrast to previous evaluations of SPR, the results of this study support the use of a fixed sampling design and show that SPR may underestimate both S&T.  相似文献   
35.
The spatiotemporal dynamics of forest-tundra communities in the 20th century have been studied in the timberline ecotone of the Polar Urals. Maps reflecting the distribution of different types of forest-tundra communities have been made, and data on the morphological and age structure of tree stands have been obtained for three time sections (the mid-1910s, 1960s, and 2000s). They show that open and closed forests have markedly expanded due to natural afforestation of the tundra and increase in the density and productivity of existing forest stands. The unidirectional pattern of plant community transition (from the tundra to closed forests) and meteorological data provide evidence that this transition has been conditioned by climate warming and increasing humidity recorded during the past 90 years.Translated from Ekologiya, No. 2, 2005, pp. 83–90.Original Russian Text Copyright © 2005 by Shiyatov, Terentev, Fomin.  相似文献   
36.
中国地表水酸化敏感性的区划   总被引:9,自引:0,他引:9  
地表水体的酸化与集水区的许多环境因子密切相关,如土壤对酸的缓冲能力、基岩中和酸沉降的能力以及土地利用方式等.其中,土壤的抗酸化能力是关键因素.因此可以根据集水区土壤、基岩和土地利用方式等信息来评估地表水在不同流量下发生酸化的可能性.本研究成功地应用已有资料和数据得到了我国地表水对酸沉降的敏感性等级,并绘制了地表水酸化敏感性区划图.结果表明,我国大部分地表水对酸化并不敏感.极易酸化和较易酸化的地表水主要分布在东北的北部地区,占所有国土面积的2.67%,是该地区强酸性漂灰土、酸性母岩和针叶林植被共同作用的结果.对酸化敏感性为中级和低级,即不易酸化的地表水主要分布在东北暗棕壤地区和南方富铝土区域,占所有国土面积的15.2%.其余82.11%国土面积上的地表水对酸化不敏感,完全不可能发生酸化.北方地区主要是由于土壤的强缓冲能力,而在南方,石灰质土壤以及耕作农田的广泛分布是最重要因素.南方重酸雨区由于土壤对酸化并不很敏感,因此在短期内不会出现大面积水体酸化现象.由于东北近年来频频出现酸雨,因此东北的酸沉降必须及早防治,以免出现大面积酸化水体.  相似文献   
37.
This paper deals with the application of satellite images to characterize some aspects of the circulation dynamics of the Tinto-Odiel estuary using turbidity patterns as ‘natural tracers’. 15 images (Landsat TM and Spot HRV) were processed to provide synoptic, instantaneous views of the circulation patterns under different environmental conditions. In addition, a comparison was made between results of oceanographic field work, using biplanes and fluorescent tracers, and satellite image turbidity patterns used as ‘ground truth’ data for specific hydroclimatic situations. This approach allowed (1) the identification and mapping of dynamic processes of interest during a theoretical tidal cycle, (2) the elaboration of additional information on the ‘flow schemes’ at the mouth of the estuary with improved spatial and temporal resolution, and (3) the supply of basic data to improve the knowledge of exchange processes between estuarine and coastal waters. The results of this study are considered to be useful for the management of the estuarine system.  相似文献   
38.
39.
Every year between one and two million African children under five die of malaria. If one adds to this the contribution of malaria to all-cause infant mortality then clearly the burden of the disease is catastrophic — a disaster quietly happening each and every year. New tools are needed urgently to support those currently available for control of the disease. An effective vaccine remains elusive. This article outlines the potential contribution to malaria control services of satellite information, which is being used by resource managers in other sectors. In particular, it highlights the lessons which can be learned from early warning systems in other areas, especially those designed to respond to famine. An appendix provides a brief introduction to satellite data and their interpretation.  相似文献   
40.
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