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341.
AbstractIn this paper, we describe and analyze the co-management institutional framework at 21 Brazilian Marine Extractive Reserves (MERs) and present the dramas of its implementation from the local manager’s perspective. We categorized the governance instruments of MERs into (i) instruments for land/sea tenure and beneficiaries’ recognition, (ii) territorial use planning, (iii) institutional arenas for discussion and deliberation, as well as (iv) public policies. Although the legal arrangements of these protected areas address fundamental dimensions of governance, we present the challenges of its implementation based on the voice of local managers. The managers are the bridge between the central government and communities, dealing with the implementation of the institutional framework in a reality of multi-level and multi-scale drama: from local to national dilemmas, from organizational to structural ones. We explore these dramas and highlight the institutional dilemmas based on the paradoxes between legalism and social emancipation. 相似文献
342.
Traditional skill scores (e.g., the threat score) used in the high-resolution verification of precipitation are affected by a “double penalty” caused by slight spatial or temporal displacements, which can lead to misleading evaluations. The fractions skill score (FSS) is a popular spatial verificaiton measure that can be used to solve these problems. It can determine useful and skillful scores by neighborhood analysis, which can be used to monitor the performance of operational forecasts. However, the FSS provides different scores at each spatial scale and it is difficult to obtain a definite score for the assessment of precipitation to analyze the temporal variabilities of daily forecasts. We previously reported a modified FSS assessment method and showed that a particular analysis scale had a significant advantage in the verification of operational forecasts of precipitation. To compensate for the lack of artificial definition in the analysis scale, we report here a new integrated score that satisfies a Gaussian weight function to average the FSS over all scales. We describe the advantages of the new score in the verification of forecasts of daily and hourly precipitation, taking forecast products from the GRAPES regional model and quantitative precipitation estimation products from the National Meteorological Information Center during June and July 2017 and investigating the differences between these results and those obtained with the traditional category score. We found that a value of 0.5 can be used as a standard for the skillful FSS in the forecast of heavy rainfall. The integrated score can maintain all the advantages seen in previous studies in the verification of daily and hourly precipitation and show excellent application prospects. The long-term verification including different seasons also find that the score can effectively improve the identification characteristics of the assessment. 相似文献
343.
Combined Separation of Cu,Fe and Zn from Rock Matrices and Improved Analytical Protocols for Stable Isotope Determination 总被引:3,自引:0,他引:3
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Paolo A. Sossi Galen P. Halverson Oliver Nebel Stephen M. Eggins 《Geostandards and Geoanalytical Research》2015,39(2):129-149
Isotope ratios of heavy elements vary on the 1/10000 level in high temperature materials, providing a fingerprint of the processes behind their origin. Ensuring that the measured isotope ratio is precise and accurate depends on employing an efficient chemical purification technique and optimised analytical protocols. Exploiting the disparate speciation of Cu, Fe and Zn in HCl and HNO3, an anion exchange chromatography procedure using AG1‐×8 (200–400 mesh) and 0.4 × 7 cm Teflon columns was developed to separate them from each other and matrix elements in felsic rocks, basalts, peridotites and meteorites. It required only one pass through the resin to produce a quantitative and pure isolate, minimising preparation time, reagent consumption and total analytical blanks. A ThermoFinnigan Neptune Plus MC‐ICP‐MS with calibrator‐sample bracketing and an external element spike was used to correct for mass bias. Nickel was the external element in Cu and Fe measurements, while Cu corrected Zn isotopes. These corrections were made assuming that the mass bias for the spike and analyte element was identical, and it is shown that this did not introduce any artificial bias. Measurement reproducibilities were ± 0.03‰, ± 0.04‰ and ± 0.06‰ (2s) for δ57Fe, δ65Cu and δ66Zn, respectively. 相似文献
344.
介绍了CORS系统的组成,结合矿业权实地核查阐述了CORS系统的应用和使用方法,通过网络RTK技术与常规GPS的比较,分析了CORS系统的优点和不足。 相似文献
345.
20世纪中期以来,麻山喀斯特山区随着周边社会环境的巨变,这些巨变冲击了麻山地区生态系统的脆弱环节,使麻山地区石漠化灾变日趋扩大。国家从20世纪60年代开始虽经多方救治,成效甚微。我们在对苗族生计方式的田野调查后发现,生息在这里的苗族积累有高效利用与精心维护喀斯特生态系统的经验和技能,发掘和利用苗族传统的地方性知识和技能,在石漠化灾变救治中具有不可替代的特殊价值。 相似文献
346.
347.
Abstract The study area is located on the Harat plain, in the central region of Iran. Four local-soil filled, free-drainage lysimeters were installed in wheat and barley farms operating under traditional farm management practices. The volume, electrical conductivity (EC), nitrate and major ions of the applied irrigation water and irrigation return flow (IRF) were measured during the growing season. The total dissolved solids (TDS) of IRF increased three to five times compared to that of the applied water. This enhancement was the same as for the chloride ion ratio, indicating the major impact of evapotranspiration in IRF salinity enhancement. Geochemical modelling using PHREEQCI confirmed the significant role of evapotranspiration and the minor effects of processes such as calcite precipitation, gypsum dissolution, fertilizer nitrification and ion exchange on the values of the IRF TDS. Time variations of EC were functions of the type of flow (preferential or matrix), lithology and soil type. The controlling parameters of the nitrate time series were the frequent applications of N fertilizer and the nitrification process. The annual N loads (NO3-N) of IRF varied from 22 to 195 kg ha-1. These variations were due to the different N loads in the applied water, the amount of fertilizer, soil texture, N uptake and volume of IRF. The annual salt loads of IRF were mainly controlled by the volume of IRF. Editor Z.W. Kundzewicz Citation Jafari, H., Raeisi, E., Hoehn, E. and Zare, M., 2012. Hydrochemical characteristics of irrigation return flow in semi-arid regions of Iran. Hydrological Sciences Journal, 57 (1), 173–185. 相似文献
348.
ABSTRACTDue to their efficiency, revitalized traditional techniques for irrigation management of scarce water resources have been suggested as a way to at least partially cope with the present water crises in the Middle East. A better irrigation management includes re-using treated wastewater in agriculture. Treated wastewater should also be used in industrial processes, thus contributing to a more efficient overall water management. However, the most important change leading to better water management is improving water efficiency in agricultural irrigation. Traditional water management techniques have an important role in many Middle East and North African (MENA) countries. Besides bringing more water to a thirsty population, they can also contribute to the societal awareness, and recognition of the great diversity of cultural and social values water has to human civilization.
EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR P. Hubert 相似文献
349.
Comparisons of cropland area from multiple datasets over the past 300 years in the traditional cultivated region of China 总被引:8,自引:5,他引:3
Land use/cover change is an important parameter in the climate and ecological simulations. Although they had been widely used in the community, SAGE dataset and HYDE dataset, the two representative global historical land use datasets, were little assessed about their accuracies in regional scale. Here, we carried out some assessments for the traditional cultivated region of China (TCRC) over last 300 years, by comparing SAGE2010 and HYDE (v3.1) with Chinese Historical Cropland Dataset (CHCD). The comparisons were performed at three spatial scales: entire study area, provincial area and 60 km by 60 km grid cell. The results show that (1) the cropland area from SAGE2010 was much more than that from CHCD moreover, the growth at a rate of 0.51% from 1700 to 1950 and -0.34% after 1950 were also inconsistent with that from CHCD. (2) HYDE dataset (v3.1) was closer to CHCD dataset than SAGE dataset on entire study area. However, the large biases could be detected at provincial scale and 60 km by 60 km grid cell scale. The percent of grid cells having biases greater than 70% (〈-70% or 〉70%) and 90% (〈-90% or 〉90%) accounted for 56%-63% and 40%-45% of the total grid cells respectively while those having biases range from -10% to 10% and from -30% to 30% account for only 5%-6% and 17% of the total grid cells respectively. (3) Using local historical archives to reconstruct historical dataset with high accuracy would be a valu- able way to improve the accuracy of climate and ecological simulation. 相似文献
350.
论述了采用两种不同作业模式对同期相同14幅1∶10 000比例尺数字线划图(简称"DLG",下同)进行更新试验。通过作业精度、投入工作量等方面的对比分析,探索研究适合"十二五"期间省级基础地理信息数据更新技术路线。 相似文献