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1.
Risk assessment is vital for cost-effective ship management in maritime industry since numerous maritime activities pose potential hazards according to the human causalities. Therefore, safety practitioners attempt to offer proactive approaches to mitigate risk as much as possible. In this context, this article presents a hybrid risk-based approach for maritime industry by adopting Fuzzy Analytic Hierarchy Process (FAHP) with fuzzy VIKOR (FVIKOR) methods under Fine-Kinney approach. To illustrate the hybrid risk-based approach, ballast tank maintenance process is handled since there are various hazards causing fatalities, severe injuries, and illness during ballast tank maintenance procedure than any other type of shipboard work. An extensive risk analysis is performed to enhance environment safety and operational reliability in maritime industry. Besides its theoretical contribution, the outcomes of the paper contribute to improve overall safety level of ship by considering potential hazards in risk management.  相似文献   

2.
Multi-criteria decision-making (MCDM) can be formally implemented by various methods. This study compares suitability of four selected MCDM methods, namely WPM, TOPSIS, VIKOR, and PROMETHEE, for future applications in agent-based computational economic (ACE) models of larger scale (i.e., over 10 000 agents in one geographical region). These four MCDM methods were selected according to their appropriateness for computational processing in ACE applications. Tests of the selected methods were conducted on four hardware configurations. For each method, 100 tests were performed, which represented one testing iteration. With four testing iterations conducted on each hardware setting and separated testing of all configurations with the–server parameter de/activated, altogether, 12800 data points were collected and consequently analyzed. An illustrational decision-making scenario was used which allows the mutual comparison of all of the selected decision making methods. Our test results suggest that although all methods are convenient and can be used in practice, the VIKOR method accomplished the tests with the best results and thus can be recommended as the most suitable for simulations of large-scale agent-based models.  相似文献   

3.
研究土壤侵蚀与景观格局变化的关系对小流域的治理开发具有重要的指导意义。本研究以实施退耕还林草、生态农业、生态旅游及科技示范的黄土高原安塞南沟特色治理小流域为研究对象,基于GIS平台和通用土壤流失方程,分析小流域1981—2018年景观格局和土壤侵蚀量的时空演化特征,并利用主成分回归法,从斑块类型水平和景观水平两个尺度分析土壤侵蚀模数与3类9个景观格局指标的关系。结果表明: 研究期间,在5种景观类型中,耕地和林地面积的时空变化主导了南沟小流域景观格局的演化,并且影响整个小流域的聚集分散程度;南沟小流域的土壤侵蚀量逐年减少,1981—2018年土壤侵蚀面积减少29.7%,侵蚀模数减少61.2%,且有73.4%的区域土壤侵蚀强度减轻;耕地和林地面积的变化决定了整个小流域土壤侵蚀模数的变化,其景观格局指数的变化方向与该景观类型土壤侵蚀的变化方向一致;退耕还林草工程是流域景观格局变化、土壤侵蚀减轻的主要原因,特色开发治理可以减弱局部地区土壤侵蚀强度。景观类型的合理化配置能有效地防治小流域土壤侵蚀,将其与特色治理开发相结合有助于实现小流域可持续高质量发展。  相似文献   

4.
Assessing soil erosion hazards and mapping the spatial distribution of soil erosion have an essential role in sustainable forest management. In this study, the potential soil erosion risk was evaluated through the Analytical Hierarchy Process (AHP) and Geographic Information Systems (GIS) in the Oltu forest planning unit, Erzurum. Seven erosion-related criteria, including slope, bedrock type, relative relief, drainage density and frequency, rainfall, and land use/land cover (LULC) were used for the present assessment. According to the AHP analysis, the slope was the most influential factor (21%) followed by bedrock type (19%), land cover (17%), and relative relief (14%) in the soil erosion process. The soil erosion risk in the study area was strongly influenced by the LULC where 59.46% is bare land with high erosion risk and 12.07%, with the lowest risk, is in an area with any forest cover. The estimated soil erosion risk was classified into five different classes namely very low, low, moderate, high, and very high. The results showed that this study area is highly prone to soil erosion. The larger proportion of the area (39.16%) is exposed to high to very high erosion, mainly determined by forest cover and geomorphology. To analyze the accuracy of the soil erosion risk map, 40 points were selected randomly in this study area. In these points, predicted values were compared to the real values obtained by Google Earth-colored images. The area under the ROC curve (AUC) method was applied to validate the efficiency of the AHP which showed a satisfactory accuracy of 81.00%. Findings presented that including the more influencing factors with a slope instead of including only the slope contributes to a more accurate erosion risk map. This study highlighted that GIS-based multi-criteria decision-making is a valuable and practical tool for decision-makers and land managers in creating soil erosion susceptibility maps and determining high-priority areas that require conservation measures for sustainable land use management by reducing the economic and ecological impacts of soil loss. Also, this approach can be practically applied in other planning units.  相似文献   

5.
Abstract

The main aim of this study is to develop and implement new integrated environmental risk assessment for transportation activities. With this purpose, environmental risks occur from transportation activities from different transportation modes which are air, road, sea and rail are determined. Transportation modes are compared with the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) approach in order to obtain importance weights and impact categories of air, soil and water are used as criteria where the weights are determined with Analytical Hierarchy Process (AHP). For the risk assessment process, Failure Mode and Effect Analysis (FMEA) has been used and prioritizations of risks are calculated with weights of the calculated transportation modes. In the study, integrated multi-criteria decision-making methods with the classic FMEA method with different categories of impacts reveal new multidimensional perspective to classic environmental risk assessment methods.  相似文献   

6.
This study was conducted to identify environmental and human health risks caused by Balarood Dam, in construction phrase. The first step, all risk-generating factors were identified using a Delphi Questionnaire. Afterwards, the identified criteria were prioritized once using the Analytical Hierarchy Process (AHP) method and then by the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). Due to the complex and uncertain nature of decision-making in times of risk, it was necessary to use more than one weighting method to ensure accuracy of weights. The results from AHP and TOPSIS revealed a mismatch in priorities; therefore, an integration method was presented blending Mean-Rank, Borda, and Copeland methods. According to the TOPSIS results, factors including cut and fill, explosion, and transportation, were first to third highest-priority risk-generating factors, respectively. Considering the results from the AHP method, factors cut and fill, drilling, and explosion were identified as first to third top-priority risk-generating factors, respectively. The results obtained from the integration method suggested that cut and fill, explosion, and drilling are the most important environmental risks at construction phase. As a general conclusion, different weighting methods can lead to different results by which the fate of a decision may be changed and it is essential to control final scores by applying more than one weighting method.  相似文献   

7.
Occupational Health and Safety (OHS) is a basis to reduce occupational accidents in an acceptable level, and it covers employee health, safety, and welfare in the workplaces. Hospitals as the largest employer group in healthcare industry in Turkey face major hazards categorized as chemical, biological, physical, ergonomic, and psychosocial risks. Although Turkey demonstrates rapid economic growth, OHS practices have not been fully put into practice, and necessary attention has not been paid to the health industry. For this reason, this paper aims to assess risks for health staff, contribute for planning of health services, and enhance regulations. A case study was carried out in a leading hospital in Turkey using a two-stage fuzzy multi-criteria approach, which provides more consistency in decision-making process and gives an appropriate final rank of hazard types. Fuzzy Analytic Hierarchy Process (FAHP) is used in weighing five risk parameters, which are severity, occurrence, undetectability, sensitivity to maintenance non-execution, and sensitivity to personal protective equipment (PPE) non-utilization. The fuzzy VIKOR (FVIKOR) approach is then applied for prioritization of hazard types in each department of the hospital. On conclusion of the hazard control hierarchy, measures are overtaken for the hazards, and areas open for improvement are presented.  相似文献   

8.
The watershed of the Ningxia-Inner Mongolia Reach of the Yellow River (NIMRYR) suffers from soil erosion by wind and water because of the wide distribution of deserts and arsenic sandstones in this region. The sediment generated by erosion fed into the Yellow River directly or by its tributaries, silting up the Yellow River and raising the elevation of the river bed. The silting of the Yellow River result in serious flood disasters in this watershed. Therefore, it is urgent to implement soil conservation projects to control wind and water soil erosion. To reach this objective, understanding the spatial and temporal variations of soil erosion in this watershed is very important. In this study, an assessment of soil erosion risk by wind and water was performed based on soil erosion models. The Integrated Wind Erosion Modeling System (IWEMS) and the Revised Wind Erosion Equation (RWEQ) were used to estimate the wind erosion modulus in this watershed, and the water erosion modulus was estimated by the Revised Universal Soil Loss Equation (RUSLE). The results show that during 2000s, the wind erosion modulus ranged from 0 to 31,440.4 t/km2/a, and the water erosion modulus was from 0 to 24,048.5 t/km2/a. Moreover, the total soil erosion modulus by wind and water has ranged from 0 to 32,792.7 t/km2/a. Due to the influence of regional weather and geomorphology, occurrences of wind and water erosion in this watershed are not identical in their spatial and temporal patterns. Based on the calculated soil erosion modulus, soil erosion risk was assessed according to the “Classification criteria for soil-erosion intensities” (SL190-2007). It was assumed that the areas with erosion intensity higher than slight were at risk of erosion; by this criterion, more than 34% of the total area of the watershed of the NIMRYR would be at erosion risk. Based on this estimation, it was also found that the NIMRYR watershed is not a region of wind–water erosion crisscross and that land-use conversions have a significant impact on soil erosion.  相似文献   

9.
In the Loess Plateau, soil erosion has not only caused serious ecological and environmental problems but has also impacted downstream areas. Therefore, a model is needed to guide the comprehensive control of soil erosion. In this study, we introduced the WEPP model to simulate soil erosion both at the slope and watershed scales. Our analyses showed that: the simulated values at the slope scale were very close to the measured. However, both the runoff and soil erosion simulated values at the watershed scale were higher than the measured. At the slope scale, under different coverage, the simulated erosion was slightly higher than the measured. When the coverage is 40%, the simulated results of both runoff and erosion are the best. At the watershed scale, the actual annual runoff of the Liudaogou watershed is 83m3; sediment content is 0.097 t/m3, annual erosion sediment 8.057t and erosion intensity 0.288 t ha-1 yr-1. Both the simulated values of soil erosion and runoff are higher than the measured, especially the runoff. But the simulated erosion trend is relatively accurate after the farmland is returned to grassland. We concluded that the WEPP model can be used to establish a reasonable vegetation restoration model and guide the vegetation restoration of the Loess Plateau.  相似文献   

10.
Abstract

The effectiveness of the traditional risk analysis approach is enhanced by the integration of the fuzzy logic and Multi-Criteria Decision Making (MCDM) methods. In fact, human decisions are ambiguous and blurred and do not fit to express with absolute numerical values. For this reason, it is more realistic to use verbal variables in modeling human decisions. In this paper, a new fuzzy based hazard evaluation approach is proposed to deal with the risk assessment process. The proposed methodology consists on MCDM with a fuzzy system which includes a hybrid structure consists the Pythagorean Fuzzy Analytic Hierarchy Process (PFAHP) method with cosine similarity, and also Neutrosophic Analytic Hierarchy Process (NFAHP) to support facing of uncertainty in the risk assessment process for asphalt production, laying and coating services which are important and should be examined in terms of occupational health and safety. To the best of our knowledge, this study is the first to propose facing uncertainty in the hazard evaluations and risk assessment for asphalt production, laying, and coating services. As an outcome of the analysis by the proposed method, according to PFAHP and NFAHP methodologies the criterions “manometer size” and “calibration” are found to be most critical factors, respectively.  相似文献   

11.
With growing concerns over changes of the living environment and ecological environment, more and more scholars have focused their researches on understanding how vegetation covers and atmospheric conditions respond to soil erosion in watersheds. Former studies show that both the natural factors such as precipitation, vegetation, slope of terrain, soil properties and human activities are the main factors to affect the amount of sediment produced by erosion in the watershed, and there are special conditions of climate and soil that are unique to loess areas for water and soil conservations. Thus the relationships between soil erosion and vegetation and precipitation are very complicated and interesting. As a loess area, the Lüergou watershed with the area of 12.1 km2 lies in west of China. The watershed was a key area of high water and soil erosion forty years ago, but the area of vegetation cover has become larger because of highly effective methods of water and soil conservation. In the factors affecting the amount of sediment produced by erosion in the study area, which is more important for soil erosion: vegetation cover or precipitation? The experts, community has discussed this question for a long time. And the Lüergou watershed has become the natural and ideal test watershed. Based on water observation data, climate data and NOAA/AVHRR NDVI images collected from 1982 to 2000 in the Lüergou watershed of loess areas, analyses of the correlation and multi-variable regression were used to discuss the relationships among the amount of sediment produced by erosion, water indexes, precipitation factors and vegetation cover. The conclusions showed that with the increase of precipitation indexes and the decrease of plant indexes, and the amount of sediment produced by erosion in the study area would become larger. In order to distinguish the influences of erosion due to human activity and natural factors, the paper introduced multi-variable regression method by standardization data to determine the relative contributing ratio to soil erosions in the study area. The conclusions showed that the contributing ratio of vegetation cover and precipitation changes were 45.7% and 54.3%. It was obvious that the influences of precipitation were larger than those of vegetation for the soil erosion in the study area.  相似文献   

12.
With growing concerns over changes of the living environment and ecological environment, more and more scholars have focused their researches on understanding how vegetation covers and atmospheric conditions respond to soil erosion in watersheds. Former studies show that both the natural factors such as precipitation, vegetation, slope of terrain, soil properties and human activities are the main factors to affect the amount of sediment produced by erosion in the watershed, and there are special conditions of climate and soil that are unique to loess areas for water and soil conservations. Thus the relationships between soil erosion and vegetation and precipitation are very complicated and interesting. As a loess area, the Lergou watershed with the area of 12.1 km2 lies in west of China. The watershed was a key area of high water and soil erosion forty years ago, but the area of vegetation cover has become larger because of highly effective methods of water and soil conservation. In the factors affecting the amount of sediment produced by erosion in the study area, which is more important for soil erosion: vegetation cover or precipitation? The experts, community has discussed this question for a long time. And the Lergou watershed has become the natural and ideal test watershed. Based on water observation data, climate data and NOAA/AVHRR NDVI images collected from 1982 to 2000 in the Lergou watershed of loess areas, analyses of the correlation and multi-variable regression were used to discuss the relationships among the amount of sediment produced by erosion, water indexes, precipitation factors and vegetation cover. The conclusions showed that with the increase of precipitation indexes and the decrease of plant indexes, and the amount of sediment produced by erosion in the study area would become larger. In order to distinguish the influences of erosion due to human activity and natural factors, the paper introduced multi-variable regression method by standardization data to determine the relative contributing ratio to soil erosions in the study area. The conclusions showed that the contributing ratio of vegetation cover and precipitation changes were 45.7% and 54.3%. It was obvious that the influences of precipitation were larger than those of vegetation for the soil erosion in the study area.  相似文献   

13.
基于137Cs示踪技术,结合土地利用变化数据,对黄土丘陵沟壑区羊圈沟小流域土壤侵蚀强度的演变过程进行了研究.结果表明:从20世纪80年代以来,该流域土地利用强度逐渐减弱;1980—2006年间,研究区坡耕地面积急剧下降,从94.9 hm2下降到0.2 hm2,乔木林地面积由0增加到51.1 hm2,灌木林地面积由0增加到19.2 hm2,果园林地面积由0增加到18.0 hm2,荒草地面积趋于稳定,由76.9 hm2增加到80.1 hm2.研究期间,不同土地利用类型的土壤侵蚀强度依次为:坡耕地>灌木林地>果园林地>荒草地>乔木林地;1980、1984、1996和2006年流域土壤侵蚀强度分别为6408.9、5362.4、4903.9和3641.4 t·km-2·a-1,侵蚀程度由强度变为中度.土壤侵蚀强度降低的主要原因是该区的水保措施和植被恢复措施.  相似文献   

14.
鲁中南山地丘陵区土壤侵蚀强度景观格局的动态变化   总被引:2,自引:0,他引:2  
史云飞  张玲玲 《生态学杂志》2012,31(8):2059-2065
以鲁中南山地丘陵区为研究区,以TM影像和地形图为源数据,借助GIS和RS技术,获取1986、1995和2004年土壤侵蚀强度数据,分析鲁中南山地丘陵区近20年来土壤侵蚀强度景观格局动态变化。结果表明:微度和轻度土壤侵蚀面积增加,而中度以上土壤侵蚀面积具有明显减小的趋势,其中轻度、强度、极强度和剧烈4种土壤侵蚀类型的面积变化比较显著;较低级别(微度、轻度和中度)土壤侵蚀强度转移率较小,较高级别(强度、极强度和剧烈)的土壤侵蚀强度转移程度较大;在景观水平上,1986—1995年斑块数量和景观形状指数增加,蔓延度指数下降,表明这期间斑块破碎度增加,连接度降低,形状变得更为复杂;而1995—2004年各指数变化趋势恰好相反。  相似文献   

15.
纸坊沟流域近60年来土地利用景观变化的环境效应   总被引:22,自引:2,他引:20  
温仲明  焦峰  张晓萍  杨勤科 《生态学报》2004,24(9):1903-1909
以黄土丘陵区纸坊沟流域为研究区 ,对该流域近 6 0 a来的土地利用景观变化的环境效应进行了较为系统的分析研究。结果表明 ,流域环境与土地利用景观变化密切相关。随着由林草植被占优的景观格局演变为由坡耕地占优的景观格局 ,流域环境状况逐步恶化 ,并在 195 8年达到最低点。 1975年后 ,随着流域治理工作的开展 ,林草植被在景观中的优势度得以逐渐恢复 ,并经历了 1995年的较为均衡的过渡阶段后 ,持续增加并重新恢复了其在景观中的优势地位。流域环境状况逐渐恢复乃至接近1938年植被未被破坏时的水平。社会经济环境因素的变化表明 ,生态环境建设不仅仅是单纯的林草植被恢复与重建的过程 ,而是一个生态和社会经济环境相互促进并有机发展和提高的过程。  相似文献   

16.
耦合过程和景观格局的土壤侵蚀水环境影响评价   总被引:1,自引:0,他引:1  
刘宇  吴炳方  曾源  张磊 《生态学杂志》2013,24(9):2581-2589
将景观格局的作用纳入到土壤侵蚀的生态环境影响评估中,具有方法上的实用意义,可为水体泥沙源区识别、评价立地侵蚀对目标水体的泥沙输出风险和流域景观格局对土壤流失抑制潜力提供一种途径.本文将RUSLE模型作为模拟立地土壤侵蚀强度的工具,考虑植被覆盖和地形对泥沙输送的阻滞作用,从点(栅格)和子流域两个尺度,采用景观格局表征方法定量评估南水北调中线水源区土壤侵蚀对河流、水库的影响.在点(栅格)尺度提出土壤侵蚀影响强度(I)指标表征土壤侵蚀对水体的泥沙输出风险;在流域尺度利用反映流域景观格局留滞泥沙能力的渗透指数(LI)指示泥沙进入水体的风险.结果表明: 耦合景观格局信息和侵蚀过程的指标能空间分布式地有效反映立地土壤侵蚀对水体泥沙输入的影响强度;LI与流域平均景观阻滞、平均植被覆盖度呈显著的指数关系, 子流域输沙模数与LI呈显著的指数回归关系.说明基于土壤侵蚀过程表征景观格局、将景观格局信息与景观土壤保持功能结合起来的评价方法,可为土壤侵蚀风险评价提供新途径.  相似文献   

17.
水利工程建设对自然保护区生态系统的影响   总被引:1,自引:0,他引:1  
温敏霞  刘世梁  崔保山  杨敏 《生态学报》2008,28(4):1663-1671
以糯扎渡水利工程及受影响的自然保护区为研究案例,在GIS支持下,应用缓冲区分析法,分析了水利工程建设前后自然保护区景观结构的梯度变化以及水利工程对景观结构的影响;选取分维数、斑块密度、优势度、聚集度等代表性指标揭示了区域景观格局的变化;在此基础上,选取自然性、多样性、稳定性和人为干扰性4项指标建立生态评价指标体系,应用层次分析法确定评价指标的权重,并对评价因子进行等级化处理,评价水利工程对影响区生态质量的影响.结果表明:不同缓冲距离内植被类型呈梯度变化,工程建设对季风常绿阔叶林、竹林、落叶季雨林有较大影响;水利工程建设使区域景观异质性增强,在缓冲距离800m范围内景观格局变化明显;建设前后受影响区生态质量评价表明,水利工程建设导致区域生态质量降低,但降幅不大.  相似文献   

18.
This study aims to identify suitable regions for grape cultivation and the areas where diseases are likely to occur in Fars Province, Iran. The study employs a multi-criteria decision-making (MCDM) model based on the Analytic Hierarchy Process (AHP) and fuzzy logic methods, taking into account the ecological requirements of grape plants. Fourteen essential parameters for grape cultivation are prepared, and interpolation maps are created for each parameter. Fuzzy maps are generated by defining membership functions, and AHP is utilized to compare and determine the importance of each factor to produce a final map of grape cultivation land suitability. The study reveals that grape cultivation is most suitable in the southern regions of Fars Province. Furthermore, the research identifies the areas where Powdery mildew, Gray mold, and GFLV diseases may occur based on rainfall and temperature levels. The study recommends against grape cultivation in the southern region due to the possibility of these diseases developing. The study employs a highly accurate regression method (R2 = 0.968 and F = 0.00001) and principal component analysis (PCA) to determine that land suitability class strongly correlates with Tmin, NDVI, LST, Total disease, Tmean, and RH. By identifying the areas suitable for grape cultivation and where pests may flourish, the necessary management can be implemented to ensure maximum harvest in the best suitable locations for grape planting.  相似文献   

19.
皇甫川流域土地利用变化与土壤侵蚀评价   总被引:13,自引:0,他引:13  
喻锋  李晓兵  陈云浩  王宏  杨明川 《生态学报》2006,26(6):1947-1956
基于“3S”技术,揭示了皇甫川流域近十多年来的土地利用变化情况,并采用通用土壤侵蚀方程(Universal Soil Loss Equation,USLE)定量研究了不同土地利用背景下的土壤侵蚀分布规律。结果表明,近十几年来流域土地利用变化剧烈,其总体趋势是城镇用地、林地、耕地和灌丛的面积逐渐增加(速率依次减小),水体、草地、沙地和棵砒砂岩面积逐渐减小(其中水体缩减的幅度最大),土地利用格局持续承受着来自当地快速城市化进程及社会经济发展和生态环境保护及建设两方面相互矛盾的巨大压力;与此同时,流域土壤侵蚀模数由1987年的16160.72t/km^2减少到2000年的13943.32t/km^2,其中6种不同土地利用类型在同一年份内土壤侵蚀模数的大小顺序为棵砒砂岩〉沙地〉耕地〉草地〉林地〉灌丛,表明林、灌措施是流域植被恢复和减少土壤侵蚀的首选,草地限制土壤侵蚀的效果也较为明显,而沙地尤其是分布面积较广的棵砒砂岩则是土壤侵蚀综合治理的难题和关键;虽然十几年来水土流式综合治理效果显著,但由于棵砒砂岩和沙地的面积仍在整个流域占有相当的比例以及耕地剧增等因素,土壤侵蚀模数仍明显高于流域土壤允许侵蚀的临界值,流域生态环境仍然处于不安全状态,有必要对未来土地利用格局进行优化以确保生态安全。最后,在讨论中阐明了流域土地利用格局调整和优化的方向。  相似文献   

20.
基于PSR方法的区域生态安全评价   总被引:14,自引:0,他引:14  
李中才  刘林德  孙玉峰  崔金荣 《生态学报》2010,30(23):6495-6503
生态安全是指一个社会的资源、环境系统能够满足经济、社会需要的同时,又不削弱其自然储量的状态。目前,广泛使用的"压力-状态-响应"(PSR)模型及层次分析法(AHP)存在一定的局限性,尚需要改进。以PSR模型为基础,选择北方针叶林、疏林、农田、荒漠灌丛、沙漠5类生态系统作为区域生态安全评价的参考系,提出了"主观能动响应力度"、"实效响应力度"的概念,综合应用了生态足迹、能值理论给出了计算生态状态指数、响应指数、压力指数的新方法,提出了计算区域生态安全指数的数学模型,增强了评价的客观性、可比性、通用性。以山东省长岛县为例,研究了生态状态、响应、压力之间的作用关系,绘制了生态安全指数的变化曲线,从时间尺度上(1990-2005年)评价生态安全的现状和发展趋势,推导出生态安全状况不断得到改善的必要条件。结果表明:虽然长岛县植被覆盖面积逐年增加,但是生态安全状况却没有得到明显改善,呈下降趋势。因此,植被存量,尤其森林植被的存量在增强生态安全等级上发挥着重要作用。从增加植被存量、加大生态恢复力度和减少生态压力方面提出了改善区域生态安全的建议与对策,为长岛县生态安全管理提供科学依据和指导。  相似文献   

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