Ivy (Hedera helix L.) dynamics in riverine forests: Effects of river regulation and forest disturbance

2006 ◽  
Vol 236 (1) ◽  
pp. 12-17 ◽  
Author(s):  
Annik Schnitzler ◽  
Patricia Heuzé
Keyword(s):  
Forest Disturbance ◽  
River Regulation ◽  
Hedera Helix ◽  
Riverine Forests

Winter Survival Evaluation of 172 Groundcovers in Northern Illinois

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 453d-453
Author(s):  
A.M. Shirazi ◽  
E.A. HedBorn ◽  
S.A. Mehaffey ◽  
A.S. Merritt
Keyword(s):  
Cold Resistance ◽  
Winter Hardiness ◽  
Winter Survival ◽  
Severe Damage ◽  
Hedera Helix ◽  
Cold Temperatures ◽  
Ajuga Reptans ◽  
Significant Damage ◽  
Cold Damage ◽  
Euonymus Fortunei

The winter hardiness of many groundcover cultivars in northern Illinois is not well-known. This study was designed to evaluate the survival of 172 plants used in the groundcover path at The Morton Arboretum. Once a month, from Sept.1997 to Jan. 1998, the plants chosen for this study were visually evaluated and their vitality rated on a scale of 1 to 5 (1 = alive, 5 = dead). All nine cultivars of Euonymus fortunei remained virtually unchanged throughout the study period. Among six cultivars of Hedera helix, only `Gold Heart' showed minor damage in November. Nine Heuchera were evaluated and all exhibited excellent resistance to cold temperatures. While all the Pulmonarias studied showed some cold damage by November, `Bielefeld Pink', `Little Blue', `Roy Davidson', Pulmonaria longifolia var. cevennensis, and Pulmonaria officinalis `Sissinghurst White' fared the best for the longest period of time. Five cultivars of Pachysandra terminalis were included in this study. None had significant damage until November, and then only rated a “2.” Of the eight Ajuga evaluated, Ajuga pyramidalis `Metallica Crispa', and Ajuga reptans `Braunherz', `Catlin's Giant', and `Gaiety', exhibited the best cold resistance. Four Polygonums varied widely in their response to cold temperatures, but all showed signs of severe damage in November. Polygonum `Border Jewel' exhibited the best tolerance, rating a “1” in October, but in November it was given a rating of “4.” Their recovery in spring will be compared.

scholarly journals Morphology and Physicochemical Properties of Alluvial Soils in Riparian Forests after River Regulation

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 329
Author(s):  
Dorota Kawalko ◽  
Paweł Jezierski ◽  
Cezary Kabala
Keyword(s):  
Large Scale ◽  
Soil Classification ◽  
River Regulation ◽  
Riparian Forests ◽  
Deep Penetration ◽  
Alluvial Soils ◽  
Soil Morphology ◽  
Groundwater Supply ◽  
Quantitative Alteration ◽  
Favorable Conditions

The elimination of flooding and lowering of the groundwater table after large-scale river regulation allow deep penetration of soils by plant roots, soil fauna, and microorganisms, thus creating favorable conditions for advanced pedogenesis. Although the changes of the morphology and properties of agriculturally used drained alluvial soils in Central Europe have been well characterized, studies in riparian forests remain insufficient. An analysis of 21 profiles of forest soils located on the Holocene river terrace (a floodplain before river regulation and embankment) in SW Poland confirmed a noticeable pedogenic transformation of soil morphology and properties resulting from river regulation. Gleyic properties were in most profiles replaced with stagnic properties, testifying to a transition from dominant groundwater supply to precipitation-water supply. The development of a diagnostic mollic and cambic horizons, correlated with the shift in soil classification from Fluvisols to Phaeozems, and in the majority, to Cambisols, demonstrated a substantial change in habitat conditions. The transformation of alluvial soils may result in an inevitable modification of forest management in the river valley, including quantitative alteration in species composition of primarily riparian forests.

scholarly journals A foci cohort analysis to monitor successful and persistent foci under Thailand’s Malaria Elimination Strategy

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Prayuth Sudathip ◽  
Suravadee Kitchakarn ◽  
Jui A. Shah ◽  
Donal Bisanzio ◽  
Felicity Young ◽  
...  
Keyword(s):  
Malaria Elimination ◽  
Proportional Hazards ◽  
Proportional Hazards Model ◽  
Forest Disturbance ◽  
Cohort Analysis ◽  
Information Criteria ◽  
Factors Associated ◽  
Malaria Burden ◽  
Hazards Model ◽  
Autochthonous Transmission

Abstract Background Thailand’s success in reducing malaria burden is built on the efficient “1-3-7” strategy applied to the surveillance system. The strategy is based on rapid case notification within 1 day, case investigation within 3 days, and targeted foci response to reduce the spread of Plasmodium spp. within 7 days. Autochthonous transmission is still occurring in the country, threatening the goal of reaching malaria-free status by 2024. This study aimed to assess the effectiveness of the 1-3-7 strategy and identify factors associated with presence of active foci. Methods Data from the national malaria information system were extracted from fiscal years 2013 to 2019; after data cleaning, the final dataset included 81,012 foci. A Cox’s proportional hazards model was built to investigate factors linked with the probability of becoming an active focus from 2015 to 2019 among foci that changed status from non-active to active focus during the study period. We performed a model selection technique based on the Akaike Information Criteria (AIC). Results The number of yearly active foci decreased from 2227 to 2013 to 700 in 2019 (68.5 %), and the number of autochthonous cases declined from 17,553 to 3,787 (78.4 %). The best Cox’s hazard model showed that foci in which vector control interventions were required were 18 % more likely to become an active focus. Increasing compliance with the 1-3-7 strategy had a protective effect, with a 22 % risk reduction among foci with over 80 % adherence to 1-3-7 timeliness protocols. Other factors associated with likelihood to become or remain an active focus include previous classification as an active focus, presence of Plasmodium falciparum infections, level of forest disturbance, and location in border provinces. Conclusions These results identified factors that favored regression of non-active foci to active foci during the study period. The model and relative risk map align with the national malaria program’s district stratification and shows strong spatial heterogeneity, with high probability to record active foci in border provinces. The results of the study may be useful for honing Thailand’s program to eliminate malaria and for other countries aiming to accelerate malaria elimination.

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