scholarly journals Rain Garden Sedges Tolerate Cyclical Flooding and Drought

HortScience ◽  
2018 ◽  
Vol 53 (11) ◽  
pp. 1669-1676
Author(s):  
Randy S. Nelson ◽  
Esther E. McGinnis ◽  
Aaron L.M. Daigh

Although sedges (Carex L. spp.) are commonly recommended for planting in rain gardens, little work has been carried out in evaluating the ability of sedge species to tolerate the challenging moisture fluctuations in this environment. Seven sedge species native to the north central United States, yellow fox sedge [Carex annectens (E.P. Bicknell) E.P. Bicknell], plains oval sedge [Carex brevior (Dewey) Mack. ex Lunell], gray’s sedge (Carex grayi J. Carey), porcupine sedge (Carex hystericina Muhl. ex Willd.), palm sedge (Carex muskingumensis Schwein.), pennsylvania sedge (Carex pensylvanica Lam.), and sprengel’s sedge (Carex sprengelii Dewey ex Spreng.), were evaluated in a greenhouse trial to determine their ability to tolerate repeated flooding and drought cycles. Treatments consisted of two flood periods (2 or 7 days), followed by one of three drought set points measured by volumetric water content (VWC) thresholds of 0.05 (severe drought), 0.10 (moderate drought), or 0.15 m3·m−3 (drought onset). Each plant was subjected to a minimum of four flooding and drought cycles. For sprengel’s sedge, plains oval sedge, gray’s sedge, and yellow fox sedge, there was no significant difference in shoot counts between severe drought, moderate drought, and drought onset treatments. Shoot mass and root mass for all sedge species were significantly reduced under the severe drought set point. Plants subjected to the 7-day flood treatment exhibited significantly increased shoot mass compared with those in the 2-day flood treatment. Plains oval sedge showed a significantly higher shoot mass than all other species under all treatments. Visible damage ratings suggest that sprengel’s sedge, plains oval sedge, gray’s sedge, and yellow fox sedge could be suitable for the rain garden environment under all but the most extreme drought conditions. Results show that plains oval sedge, yellow fox sedge, and gray’s sedge may be able to tolerate harsh flooding and drought cycles that can occur in rain gardens. For the remaining species, supplemental irrigation of rain gardens should be considered during drought.

2021 ◽  
Vol 9 ◽  
Author(s):  
Jesús Rascón ◽  
Wildor Gosgot Angeles ◽  
Lenin Quiñones Huatangari ◽  
Manuel Oliva ◽  
Miguel Ángel Barrena Gurbillón

Climate change and population growth have heavily impacted the ecosystem’s water resources, essential for anthropogenic activities. These also apply to the Andean city of Chachapoyas, located in the north of Peru, which has gone through a substantial population increase in recent years, therefore increasing its water demand. This research aimed to assess dry and wet events from 1981 to 2019 that have taken place in Chachapoyas, by applying the Standardized Precipitation Index (SPI), and the Standardized Precipitation Evapotranspiration Index (SPEI). These events were periodically characterized, and the index relationship was determined at different timescales. The SPI and SPEI indices were calculated at the city’s only weather station for timescales of 3, 6, 12, and 24 months using climatic data. The indices showed a remarkably consistent behavior for timescales of 12 and 24 months detecting an extreme drought event in 1993, while for timescales of 3 and 6 months a severe drought event was detected in the same year. Contrastingly, there has been an increase in extreme wet events in the last decade, hence Chachapoyas is categorized between "moderate drought" and “moderate wet”. It should be noted that the indices have a high correlation between them when calculated for the same timescale. The results were statistically significant (p < 0.05). Considering the results obtained related to dry and wet events and their relation with economic activities such as environmental management, we can conclude that the SPI and SPEI indices are useful and valuable tools for local and regional governments.


2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Meijian Yang ◽  
Denghua Yan ◽  
Yingdong Yu ◽  
Zhiyong Yang

Under the background of climate change, the monthly accumulated precipitation and monthly averaged temperature of 47 meteorological stations in and around Haihe River Basin (HRB) were analyzed using Standardized Precipitation Evapotranspiration Indices (SPEI) to obtain the temporal variability and spatial distribution of different drought levels during the last 50 years with the support of GIS. The results show that(1)from 1961 to 2010 the drought frequency and degree in annual and seasonal scale are rising and the affecting areas of all degrees of drought have a temporal variability of increasing trend. The ratios that the influencing area of drought, light drought, moderate drought, severe drought, and extreme drought account for the whole HRB area are increasing with gradients of 0.64%/a, 0.18%/a, 0.31%/a, 0.14%/a, and 0.01%/a, respectively, and(2)there is a climate break point which occurred in 1990; after the comparison of the drought happening probability between 1961 and 1990 and between 1991 and 2010, all degrees of drought occurrence probability have a remarkable rising trend, and the drought concentrating regions moved from the north HRB to the central HRB.


Irriga ◽  
1999 ◽  
Vol 4 (3) ◽  
pp. 139-144 ◽  
Author(s):  
Gianini Peixoto Bezerra Lima ◽  
José Vanglesio de Aguiar ◽  
Raimundo Nonato Távora Costa ◽  
Vital Pedro da Silva Paz

RENDIMENTO DE CULTIVARES DE CAUPI (Vigna unguiculata L Walp.) SUBMETIDAS À DIFERENTES LÂMINAS DE IRRIGAÇÃO1       Gianini Peixoto Bezerra Lima José Vanglesio de Aguiar Raimundo Nonato Távora Costa Universidade Federal do Ceará – Departamento de Engenharia Agrícola. Campus do Pici. Bloco 804. CEP 60455-760 – Fortaleza-CE Vital Pedro da Silva Paz Escola Superior de Agricultura Luiz de Queiroz – Departamento de Engenharia Rural, bolsista da FAPESP. Av. Pádua Dias, 11 – Caixa Postal 11. 13418-900 – Piracicaba-SP       1 RESUMO       O caupi é um dos cultivos mais tradicionais do Norte e Nordeste do Brasil, constituindo alimento básico nestas regiões. Com este trabalho foi possível estabelecer relações entre a quantidade de água aplicada e produtividade de grãos, para três variedades de feijão caupi submetidas a diferentes lâminas de água. Para caracterização das lâminas de água foi utilizado um sistema de irrigação por aspersão convencional em linha. O controle da irrigação foi realizado a partir de tensiômetros instalados à 15 cm de profundidade. Os resultados mostraram que: i) a cultivar João Paulo II apresentou melhores resultados de produtividade para as lâminas de água aplicadas que variaram de T1 = 291,8 mm a T5 = 141,2 mm; ii) sob condições de reduzida disponibilidade de água, ou seja, menor lâmina aplicada, não ocorreu diferença estatística  para a produtividade entre as cultivares estudadas; e iii) para as condições do estudo, a cultivar Setentão apresentou a menor taxa de redução do produto marginal.       UNITERMOS: caupi, irrigação, função de produção       LIMA, G. P. B., AGUIAR, J. V., COSTA, R. N. T., PAZ, V. P. S. Responses OF cowpea cultivars (Vigna unguiculata L Walp) at differents irrigation deficits     2 ABSTRACT       The caupi is one of the most traditional cultivation of the north and northeast - Brazil, constituting a basic food in these areas. With this work it was possible to establish relationships between the amount of water applied and productivity of grains, for three caupi varieties submitted to different irrigation sheets. To diferentiate water depths in the irrigation system, the aspersion in line was used. The control of the irrigation was accomplished using tensiometers installed to 15 cm of depth. The results showed that: i) the João Paulo II variety presented better productivity for the applied water depths; ii) under reduced conditions of water avai lability for study conditions, these was no significant difference in the productivity reached among the cultivars studied; and iii) for the conditions of the study, the variety Setentão presented the smallest rate of reduction of the marginal product.       KEYWORDS: cowpea, irrigation, production function  


Author(s):  
Reza Mohebbati ◽  
Yasamin Kamkar-De ◽  
Mohammad Naser Shafei

Objective: Our previous studies showed the antihypertensive effect of Ribes khorassanicum (R. khorassanicum), a medicinal herb growing in the North Khorasan Province of Iran. For further evaluation, the present study investigated the effect of n-hexane (HX), ethyl acetate (EA), and aqueous (AQ) fractions of hydroalcoholic R. khorassanicum extract on cardiovascular responses in angiotensin II (AngII) and NG-nitro-L-arginine methyl ester (L-NAME) hypertensive rats. Methods: Wistar rats were randomly divided into 11 groups (n=5): 1) control, 2) AngII (50 ng/kg, i.v), 3) AngII + losartan (10 mg/kg, i.p), 4) L-NAME (10 mg/kg, i.v), 5) L-NAME+ sodium nitroprusside (SNP) (50 mg/kg, i.p), 6,7,8) one dose of each fraction of R. khorassanicum (AQ/EA/HX (50 mg/kg, i.p)) +AngII, and 9,10,11) one dose of each fraction of R. khorassanicum (AQ/EA/HX (50 mg/kg, i.p)) + L-NAME. Treated rats received three fractions 30 min before the injection of L-NAME and AngII in separate groups. The cardiovascular parameters were recorded by the Power Lab instrument via an angiocath inserted into the femoral artery. The peak changes (∆) of mean arterial pressure (MAP), systolic blood pressure (SBP), and heart rate (HR) in treated groups were compared with those of the hypertensive and control groups. Result: AngII and L-NAME significantly increased ∆MAP and ∆SBP and attenuated by pretreatment of LOS and SNP, respectively. Pretreatment with polar (AQ) and semipolar (EA) fractions of R. khorassanicum reduced the peak changes of MAP and SBP in both AngII and L-NAME-treated groups. Only the fraction of the herb attenuated the HR increased in the L-NAME group. The HR in other groups did not demonstrate any significant difference. Conclusion: All fractions of R. khorassanicum have an antihypertensive effect. However, the effect of polar fractions is more salient. It is also conceivable that the antihypertensive effect of fractions is mostly mediated by the inhibition of AngII.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kyung Seok Kim ◽  
Kevin J. Roe

AbstractDetailed information on species delineation and population genetic structure is a prerequisite for designing effective restoration and conservation strategies for imperiled organisms. Phylogenomic and population genomic analyses based on genome-wide double digest restriction-site associated DNA sequencing (ddRAD-Seq) data has identified three allopatric lineages in the North American freshwater mussel genus Cyprogenia. Cyprogenia stegaria is restricted to the Eastern Highlands and displays little genetic structuring within this region. However, two allopatric lineages of C. aberti in the Ozark and Ouachita highlands exhibit substantial levels (mean uncorrected FST = 0.368) of genetic differentiation and each warrants recognition as a distinct evolutionary lineage. Lineages of Cyprogenia in the Ouachita and Ozark highlands are further subdivided reflecting structuring at the level of river systems. Species tree inference and species delimitation in a Bayesian framework using single nucleotide polymorphisms (SNP) data supported results from phylogenetic analyses, and supports three species of Cyprogenia over the currently recognized two species. A comparison of SNPs generated from both destructively and non-destructively collected samples revealed no significant difference in the SNP error rate, quality and amount of ddRAD sequence reads, indicating that nondestructive or trace samples can be effectively utilized to generate SNP data for organisms for which destructive sampling is not permitted.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Noorfariza Nordin ◽  
Suhaily Mohd Hairon ◽  
Najib Majdi Yaacob ◽  
Anees Abdul Hamid ◽  
Seoparjoo Azmel Mohd Isa ◽  
...  

Abstract Background People with type 2 diabetes mellitus (T2DM) are best managed by a chronic care model that is associated with enhanced quality of care and improved patient outcome. Assessing patients’ perceived quality of care is crucial in improving the healthcare delivery system. Hence, this study determined the perceived quality of care among people with T2DM and explored its associations with (i) sociodemographic and clinical characteristics and (ii) types of healthcare clinics to guide future planning. Methods A cross-sectional study involving 20 primary healthcare clinics in the North East Region of Peninsular Malaysia and people with T2DM as the sampling unit was conducted from February to May 2019. The pro forma checklist, interview-guided Skala Kepuasan Interaksi Perubatan-11, and Patient Assessment of Chronic Illness Care (Malay version; PACIC-M) questionnaire were used for data collection. Univariate analysis and linear regression were used to determine the status of perceived quality of care and the factors associated with the perceived quality of care, respectively. Results Overall, data from 772 participants were analyzed. The majority was from the Malay ethnic group (95.6%) with a mean (standard deviation [SD]) glycated hemoglobin A1c (HbA1c) level of 8.91% (2.30). The median (interquartile range [IQR]) of the number of medical officers available at each clinic was 6 (7), with Family Doctor Concept (FDC) clinics having a higher number of medical officers than non-FDC clinics (p = 0.001). The overall mean (SD) PACIC-M score was 2.65 (0.54) with no significant difference between scores of patients treated in the two clinic types (p = 0.806). Higher perceived quality of care was associated with lower number of medical officers (adjusted regression coefficient [Adj.β], − 0.021; p-value [p], 0.001), and greater doctor–patient interaction in all domains: distress relief (Adj.β, 0.033; p, < 0.001), rapport (Adj.β, 0.056; p, < 0.001), and interaction outcome (Adj.β, 0.022; p, 0.003). Conclusion Although there was no significant difference found between clinic type, this study reflects that patients are comfortable when managed by the same doctor, which may support a better doctor-patient interaction. A larger specialized primary care workforce could improve diabetes care in Malaysia.


2017 ◽  
Vol 22 (2) ◽  
pp. 5-17
Author(s):  
Mandy Harrison ◽  
Lisa Gross ◽  
Jennifer McGee

The purpose of this study is to examine how participation in the North Carolina Environmental Educator (NCEE) program influences the individual's perceived self-efficacy. Specifically, this study examines the impact of NCEE certification on participants’ perceived personal teaching self-efficacy. This study compared personal teaching efficacy scores of certified environmental educators, non-certified environmental educators, and licensed schoolteachers. The study found significant differences in teaching efficacy between certified and non-certified environmental educators, as well as certified environmental educators and licensed school teachers. In addition, the study found no significant difference in efficacy scores between NCEE certified licensed school teachers and NCEE certified environmental educators. Results of this study indicate a link between environmental education certification and higher personal teaching efficacy.


PLoS ONE ◽  
2015 ◽  
Vol 10 (9) ◽  
pp. e0139188 ◽  
Author(s):  
Laura Aldrich-Wolfe ◽  
Steven Travers ◽  
Berlin D. Nelson

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