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991.
Alexandre Marco da Silva Lucas Hubacek Tsuchiya Pablo Bettio Mendes Thiago Philipe de Camargo e Timo Artemio Cerd 《环境质量管理》2019,29(1):125-137
Soil erosion and the invasion of exotic plant species are major constraints to achieve sustainable development around the world. Currently, we find few products devoted concomitantly to combatting soil erosion as well as the establishment of unwanted exotic plants. In this paper, we introduce a new product, called herein a bioblanket, that protects the soil and impedes the establishment of exotic plant species. This product is of simple design, and to manufacture it, we use two biodegradable materials: jute tissue and grass wastes. We designed this product to combat soil erosion and the germination and establishment of new, unwanted, invasive plant species. In this paper, we describe our evaluation of how successful this product was in terms of improving the chemical attributes of soil. We also identified the product's potentialities and weaknesses by means of strengths, weaknesses, opportunities, and threats (SWOT) analysis. The bioblanket ameliorated the chemical attributes of the soil, as evidenced especially by the neutralization of acidity (8.5%) and aluminum toxicity (33%), and by an increment in nutrients concentration. We argue that after adequate treatment and management, the residues of plants that are normally considered unwanted materials can be transformed into a raw material to control the propagation of unwanted plant species, and concomitantly control soil erosion while improving the chemical conditions of the soil. The improvement of the soil chemical attributes was one of the main positive effects reported through the SWOT analysis. In addition, the SWOT analysis revealed some features that need improvement in future generations of the product, but we argue that these features do not impede the benefits for the use of the product in its present form. 相似文献
992.
为了提高绩效管理的科学性,实现对安全绩效的预测分析,针对空管运行系统的动态性、复杂性和延迟特性,引入系统动力学方法。首先,从管理和结果的角度分析指标间的因果关系,然后在因果图的基础上:1)采用网络层次分析法计算指标权重;2)建立绩效评价的系统动力学模型,由指标权重和评分规则确定指标间的关系方程,进行仿真预测,得到基于指标关系网络的绩效趋势。从查找绩效下降原因和绩效改进措施两方面分析绩效预测的应用,结果表明,运用系统动力学方法分析绩效,不仅可以逆向找到影响绩效的关键指标,还能提前预测决策变化对绩效的影响,保证决策的有效性,提高系统的安全产出。 相似文献
993.
为降低中巴公路沿线溜石灾害风险,以中巴公路K777桩处溜石坡为研究对象,定性分析溜石崩塌体运动特征并设计格栅挡墙防护结构。采用有限差分与离散元耦合方法对溜石灾害进行数值模拟,定量分析溜石崩塌体运动状态及公路挡墙动力冲击响应。结果表明:不同粒径下溜石平均速度变化趋势相同,溜石崩塌体运动速度与溜石粒径呈正相关,溜石在自然条件下对公路挡墙冲击集中且受力较大,通过布置格栅挡墙可降低公路挡墙受力,分散溜石冲击,有效拦截大粒径溜石,降低溜石灾害影响。在相同格栅挡墙孔径下,降速效果与溜石粒径呈负相关。可通过考察溜石坡实际情况设计格栅挡墙尺寸,降低中巴公路沿线溜石灾害风险。 相似文献
994.
基于MATLAB的湘江流域工业固体废物灰色预测 总被引:3,自引:0,他引:3
对灰色预测原理及其建模步骤作了系统介绍。借助MATLAB软件建立等维灰数递补残差修正动态模型预测湘江流域未来10年工业固体废物年产量,以期为湘江流域今后工业固体废物的管理、污染防治工作提供科学依据。结果表明:(1)用此模型进行预测,相对误差均在5%以下,预测精度较高,取得了较理想的预测效果;(2)湘江流域未来10年工业固体废物年产量预测值呈指数趋势增长,年增长率为8%~12%,到2016年湘江流域工业固体废物年产量预计将达到7645.01万t。 相似文献
995.
996.
可持续发展目标下环境——社会经济(Ev—SEc)复合系统评价预测指标体系 总被引:1,自引:0,他引:1
欧阳洁 《城市环境与城市生态》2003,16(1):55-58
对国内外“环境——社会经济”(Ev—SEc)复合系统已有的评价预测指标体系研究进行了简要的评述,从(Ev—SEc)复合系统发展要求的代际公平的角度出发,重新构建了充分体现可持续发展目标下(Ev—SEc)复合系统发展的协调性及持久性特征,动态整合(Ev—SEc)复合系统可持续发展的科学内涵,且多因素相容、质量和水平并列,方向和大小并存、时间和空间交叉的立体的全方位的评价预测指标体系框架,从而实现了可持续发展主题思想下各类松散描述指标的合理聚合。并将该新的评价预测指标体系用于广州市(Ev—SEc)复合系统可持续发展状况的实际仿真评价预测及时空比较,得出的广州市(Ev—SEc)复合系统可持续发展状况目前为弱可持续发展的评价结论,且预测未来正在呈现由弱可持续发展逐渐向强可持续发展过渡的动态变化趋势。 相似文献
997.
TIM P. LYNCH 《Conservation biology》2006,20(5):1466-1476
Abstract: Theoretical models of marine protected areas (MPAs) that explore benefits to fisheries or biodiversity conservation often assume a dynamic pool of fishing effort. For instance, effort is homogenously distributed over areas from which subsets of reserves are chosen. I tested this and other model assumptions with a case study of the multiple-use Jervis Bay Marine Park. Prior to zoning of the park I conducted 166 surveys of the park's recreational fisheries, plotting the location of 16,009 anglers. I converted these plots into diagrams of fishing effort and analyzed correlates between fishing and habitat and the effect of two reserve designs—the draft and final zoning plans of the park—on the 15 fisheries observed. Fisheries were strongly correlated with particular habitats and had negatively skewed and often bimodal spatial distribution. The second mode of intensely fished habitat could be 6 SD greater than the fishery's mean allocation of effort by area. In the draft-zoning plan, sanctuary zone (no-take) area and potential subduction of fishing effort were similar. In the final plan, which was altered in response to public comment, the area of sanctuary zone increased, and the impact on fishing effort decreased. In only one case was a fishery's most intensely targeted location closed to fishing. Because of the discriminating manner with which fishers target habitats, if simple percentage targets are used for planning, sanctuary location can be adjusted to avoid existing fishing effort. According to modeled outcomes, the implication of this may be diminished reserve effectiveness. To address this, reserve area should be implicitly linked to subducted fishing effort when promoting or modeling MPAs. 相似文献
998.
999.
1000.
苯酚在土壤中吸附的试验研究 总被引:7,自引:0,他引:7
采用动态法研究苯酚在不同土壤中的有吸附过程,试验结果表明,土壤的腐殖质含量,PH值,目数,含水率都对吸附过程产生影响。 相似文献