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Economic damages of hurricanes and tropical cyclones are increasing faster than the populations and wealth of many coastal areas. There is urgency to update priorities of agencies engaged with risk assessment, risk mitigation, and risk communication across hundreds or thousands of water basins. This paper evaluates hydrology and social vulnerability factors to develop a risk register at a subbasin scale for which the priorities of agencies vary by storm scenario using publicly available satellite-based Earth observations. The novelty and innovation of this approach is the quantification and mapping of risk as a disruption of system order, while using social vulnerability indices and sensor data from disparate sources. The results assist with allocating resources across basins under several scenarios of hydrology and social vulnerability. The approach is in several parts as follows: first, a baseline order of basins is defined using the CDC/ATSDR social vulnerability index (SVI). Next, a set of storm scenarios is defined using Earth Observations and modeled data. Next, a swing-weight technique is used to update factor weights under each scenario. Lastly, the importance order of basins relative to the baseline order is used to compare the risk of scenarios across the study area. The risk is thus quantified (by least squares difference of order) as a disruption to the ordering of basins by social and hydrologic factors (i.e., SVI, precipitation, wind speed, and soil moisture), with attention to the most disruptive scenarios. An application is described with extensive mapping of hydrologic basins for Hurricane Ian to demonstrate a versatile method to address uncertainty of scenarios of storm nature and extent across coastal mega-regions.

期刊论文 2024-09-01 DOI: 10.1061/AJRUA6.RUENG-1228 ISSN: 2376-7642

Wood density (WD) is a key functional trait for its importance in tree performance and in biomass calculations of forests. Yet, the variation of WD among different woody tree parts, how this varies across ecosystems, and how this influences estimates of forest carbon stocks remains little understood, particularly for diverse tropical forests such as the Amazon. We assembled a dataset on stem and twig wood density from 119 tree species in three different Amazonian ecosystem types that differ considerably in soil nutrition and flooding: non-flooded forest (Terra Firme), white-water floodplain forest (V & aacute;rzea) and black-water floodplain forest (Igap & oacute;) to investigate (i) variation of stem and twig wood density across ecosystems, (ii) the relationships between stem and twig wood density and how these relationships vary across ecosystems. Wood density varied substantially across ecosystems. V & aacute;rzea species showed lower mean WD for stems compared to Terra firme, while Igap & oacute; species showed higher WD for twigs compared to the other ecosystems. Twig and stem wood density were positively related (R2adj = 0.47) with similarly increasing rates across ecosystems, although average WD values differed between Terra firme and Igap & oacute;. For any given twig density, stem density tends to be lower in floodplain environments but higher in Terra firme, a habitat-specific pattern of wood density variation within trees that may emerge from differences in the function of stem and twig wood for growth and survival in ecologically differentiated environments. Our results show how ecosystem has strong impacts on how trees allocate resources to different woody tissues, suggesting contrasting ecological strategies linked to ecosystem constraints. Our results suggest that greater consideration of the variation of WD within trees and how these changes across ecosystems might lead to more accurate estimates of above-ground biomass in Amazonia.Read the free Plain Language Summary for this article on the Journal blog. A densidade da madeira (WD) & eacute; um tra & ccedil;o funcional chave devido a sua import & acirc;ncia na performance das & aacute;rvores e para os c & aacute;lculos de biomassa em florestas. Entretanto, pouco se conhece sobre a varia & ccedil;& atilde;o da WD entre diferentes partes das plantas, se tal varia & ccedil;& atilde;o muda entre ecossistemas, e como isto influencia as estimativas de estoque de carbono, principalmente em florestas tropicais muito diversas como a Amaz & ocirc;nia. N & oacute;s utilizamos um conjunto de dados de densidade da madeira do tronco e do ramo de 119 esp & eacute;cies de & aacute;rvores de tr & ecirc;s tipos de ecossistemas amaz & ocirc;nicos: florestas de terra firme, florestas alag & aacute;veis de & aacute;guas brancas (V & aacute;rzea) e florestas alag & aacute;veis de & aacute;guas pretas (Igap & oacute;s) e investigamos (i) a variabilidade da densidade da madeira do tronco e do ramo entre ecossistemas, (ii) e a rela & ccedil;& atilde;o entre a densidade da madeira do tronco e a do ramo, e como esta rela & ccedil;& atilde;o varia entre os ecossistemas. A densidade da madeira variou consideravelmente entre os ecossistemas. As esp & eacute;cies de V & aacute;rzea tiveram WD m & eacute;dia do tronco menor comparada a Terra firme, enquanto as esp & eacute;cies de Igap & oacute; tiveram WD m & eacute;dia do ramo maior comparada aos outros ecossistemas. A densidade do ramo e do tronco tiveram correla & ccedil;& atilde;o positiva (R(2)adj = 0.47) e taxas de aumento similares entre os ecossistemas, mas com diferen & ccedil;a nos valores m & eacute;dios de densidade entre Terra firme e Igap & oacute;. Para um dado valor de WD do ramo, a WD do tronco tende a ser menor nas florestas alag & aacute;veis, por & eacute;m maior na Terra firme, um padr & atilde;o de varia & ccedil;& atilde;o na densidade das & aacute;rvores espec & iacute;fico do habitat, que pode surgir de diferen & ccedil;as nas fun & ccedil;& otilde;es do tronco e do ramo para o crescimento e sobreviv & ecirc;ncia das esp & eacute;cies em ambientes ecologicamente distintos. N & oacute;s mostramos como os ecossistemas impactam a aloca & ccedil;& atilde;o de recursos das & aacute;rvores em diferentes tecidos da madeira, sugerindo a exist & ecirc;ncia de estrat & eacute;gias ecol & oacute;gica contrastantes associadas as restri & ccedil;& otilde;es ambientais. Nossos resultados sugerem que considerar a varia & ccedil;& atilde;o da WD de uma & aacute;rvore e como tal varia & ccedil;& atilde;o muda entre ecossistemas pode propiciar estimativas mais acuradas de biomassa na Amaz & ocirc;nia. Read the free Plain Language Summary for this article on the Journal blog.image

期刊论文 2024-07-01 DOI: 10.1111/1365-2435.14572 ISSN: 0269-8463

Aeluropus lagopoides, a dominant palatable species in various sabkha and coastal regions of Saudi Arabia, can withstand harsh saline environments through phenotypic plasticity. When subjected to grazing, how A. lagopoides adapt phenotypically is currently unknown. There is a breakage in the chain of study on the spatial and temporal expansion strategy of A. lagopoides plants when subjected to different grazing stresses in different saline soil habitats. A grazing experiment was conducted to investigate the phenotypic plasticity and resource allocation pattern response of A. lagopoides in different saline soils. Individual A. lagopoides rhizomes from five saline regions were grown and exposed to varied grazing treatments in the form of clipping, viz; light, moderate, and heavy grazing, as compared to a grazing exclusion control. Our results showed that heavy grazing/clipping significantly decreased the shoot system and above-ground biomass in high-saline region plants in the early season. Plant length, root length, root and shoot biomass, the number of stolons, average stolon length, leaf area, and SLA of A. lagopiodes responded significantly to grazing intensities. A. lagopoides from the Qareenah, Qaseem, and Jizan regions were more tolerant to light grazing than A. lagopoides from the Salwa and Jouf regions. Light grazing showed significantly good re-growth, especially during the late season. Light grazing decreased the synthesis of chlorophyll content. Also, A. lagopiodes reduced the risk caused by reactive oxygen species via the increased accumulation of proline content. Overall, plants adapted to different morphological and physiological strategies to tolerate different levels of grazing intensities by adapting their morphological attributes. Though heavy grazing damages the plant, light and moderate grazing can be allowed to maintain the productivity and economic benefits of sabka habitats where soil conditions are moderately saline.

期刊论文 2024-01-01 DOI: 10.3390/agronomy14010144
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