A Case Study of Waterhyacinth (Eichhornia crassipes) Control in Puerto Rico Using Glyphosate and Hand Removal

2021 ◽  
pp. 1-26
Author(s):  
Wilfredo Robles ◽  
Edda L. Martínez
Keyword(s):  
Puerto Rico ◽  
Invasive Plant ◽  
Control Method ◽  
Freshwater Wetlands ◽  
Management Tool ◽  
Untreated Plot ◽  
San Jose ◽  
Neochetina Eichhorniae ◽  
Water Ph ◽  
Wildlife Refuges

Abstract Waterhyacinth is an aquatic invasive plant that is widespread in Puerto Rico where it negatively effects estuaries, freshwater wetlands, potable water reservoirs, and wildlife refuges. Specifically, the tropical estuary San Juan Bay Estuary (SJBE) has been impacted with the presence of waterhyacinth. Infestations have led to a reduction of water circulation in the system as well as facilitating the establishment of invasive fauna. Therefore, a field study was conducted in a cove between Laguna San Jose and Peninsula Cantera to assess the use of glyphosate and hand removal as a management tool for waterhyacinth control. Aquatic macroinvertebrates and water quality were also monitored as a measure of environmental impact due to management activities. Results indicated that two weeks after glyphosate application, waterhyacinth biomass was significantly reduced to 0.27 kg DW m−2 at the treated plot as compared to untreated plot that yielded 0.62 kg DW m−2. Fresh weight of waterhyacinth decreased more than 90% when hand removal was used as compared to glyphosate treatment. Dissolved oxygen and water pH were not significantly different between sites however, water salinity increased to 8-9 ppt at both plots caused by tidal activity. The order Hemiptera followed by Sarcoptiformes were common at the aquatic macroinvertebrate community. Macroinvertebrate species found associated with waterhyacinth and considered natural enemies were: Orthogalumna terebrantis, Neochetina eichhorniae, Niphograpta albiguttalis. The use of glyphosate to manage waterhyacinth at the Laguna San Jose was useful as a short-term control method and its efficacy may be enhanced over time with follow up applications in combination with hand removal.

scholarly journals Concentración de los macronutrientes del suelo en áreas de pastoreo del departamento de Caquetá, Amazonia colombiana

2020 ◽  
Vol 21 (3) ◽  
pp. 1-12
Author(s):  
Jennifer Zambrano-Yepes ◽  
Wilmer Herrera-Valencia ◽  
Pablo Andrés Motta-Delgado
Keyword(s):  
Puerto Rico ◽  
San Jose ◽  
Para Determinar

El establecimiento de ganadería en el noroccidente de la Amazonia colombiana disminuye los macronutrientes en el suelo y afecta los sistemas productivos. El objetivo del estudio fue obtener información de diagnóstico sobre la concentración de los macronutrientes del suelo en lomerío sometidos a pastoreo en nueve municipios del departamento de Caquetá. Se realizaron 463 muestreos de suelo al azar para determinar la concentración en mg/kg de nitrato (N-NO3), fósforo (P), potasio (K), calcio (Ca), magnesio (Mg) y azufre (S). Se realizaron análisis de varianza (Anova) y se compararon las medias mediante la prueba de Tukey (p < 0,05). Se evidenció una concentración de N-NO3 con medias de hasta 90,57 mg/kg en San José del Fragua, El Doncello y San Vicente del Caguán, que presentan diferencias estadísticas con respecto a Puerto Rico (18,83 mg/kg) y La Montañita (5,24 mg/kg). La concentración de P en San Vicente del Caguán, Puerto Rico y San José del Fragua tiene una media entre 1,4 mg/kg y 1,8 mg/kg, y presenta diferencias significativas respecto a La Montañita (3,5 mg/kg). La concentración de K, con una media entre 46,9 mg/kg y 74,2 mg/kg, no presentó diferencias significativas entre las localidades. San Vicente del Caguán fue el único municipio que presentó diferencias significativas de Ca (1.000,9 mg/kg) y Mg (226 mg/kg) en relación con los demás. En cuanto a S, se observaron diferencias significativas entre Cartagena del Chairá (2,29 mg/kg) y San José del Fragua (4,29 mg/kg). En conclusión, se evidenció una generalizada baja concentración de macronutrientes en comparación con los valores óptimos de suelos tropicales.

scholarly journals Assessment of the Rheological Behavior of Polymer–Oxidant Mixtures and the Influence of the Groundwater Environment on Their Properties

Water ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1698
Author(s):  
Qi Xu ◽  
Jiajun Chen ◽  
Xinran Song
Keyword(s):  
Xanthan Gum ◽  
Control Method ◽  
Shear Thinning ◽  
Mobility Control ◽  
Retention Rates ◽  
Viscosity Reduction ◽  
Leading Role ◽  
Salt Ions ◽  
Groundwater Environment ◽  
Water Ph

Shear-thinning polymers have been introduced to contaminant remediation in the subsurface as a mobility control method applied to mitigate the inefficient delivery of remedial agents caused by geological heterogeneity. Laboratory experiments have been conducted to assess the compatibility of polymers (xanthan and hydrolyzed polyacrylamide (HPAM)) and oxidants (KMnO4 and Na2S2O8) through quantitative evaluation of the viscosity maintenance, shear-thinning performance, and oxidant consumption. The mechanism that causes viscosity loss and the influence of the groundwater environment on the mixture viscosity were also explored. The xanthan–KMnO4 mixture exhibited the best performance in both viscosity retention and shear-thinning behavior with retention rates higher than 75% and 73.5%, respectively. Furthermore, the results indicated that xanthan gum has a high resistance to MnO4− and that K+ plays a leading role in its viscosity reduction, while HPAM is much more sensitive to MnO4−. The viscosity responses of the two polymers to Na2S2O8 and NaCl were almost consistent with that of KMnO4; salt ions displayed an instantaneous effect on the solution’s viscosity, while the oxide ions could cause the solution’s viscosity to decrease continuously with time. Since xanthan exhibited acceptable oxidant consumption as well, xanthan–KMnO4 is considered to be the optimal combination. In addition, the results implied that the effects of salt ions and the water pH on the mixture solution could be acceptable. In the 2D tank test, it was found that when xanthan gum was introduced, the sweeping efficiency of the oxidant in the low-permeability zone was increased from 28.2% to 100%. These findings demonstrated the feasibility of using a xanthan–KMnO4 mixture for actual site remediation.

The first account of the mating disruption technique for the control of California red scale, Aonidiella aurantii Maskell (Homoptera: Diaspididae) using new biodegradable dispensers

2009 ◽  
Vol 99 (4) ◽  
pp. 415-423 ◽  
Author(s):  
S. Vacas ◽  
C. Alfaro ◽  
V. Navarro-Llopis ◽  
J. Primo
Keyword(s):  
Sex Pheromone ◽  
Pest Management ◽  
Chemical Communication ◽  
Field Trial ◽  
Mating Disruption ◽  
Control Method ◽  
Insect Pests ◽  
Environmentally Friendly ◽  
Untreated Plot ◽  
Aonidiella Aurantii

AbstractSemiochemical-based pest management programs have been increasingly used to provide environmentally friendly methods for the control of major insect pests. The efficacy of the mating disruption technique has been demonstrated for several moth pests. Unfortunately, not many experiments on mating disruption to control diaspididae species have been documented. In this work, biodegradable dispensers for mating disruption with increasing pheromone loads were used in order to study the potential of this technique for the control of Aonidiella aurantii Maskell. Field trial results demonstrated that dispensers loaded with 50 mg (a.i.) (20 g ha−1) and 100 mg (a.i.) (40 g ha−1) of sex pheromone were the most suitable, achieving significant reductions in male catches, compared to an untreated plot. In treated plots, virtually a 70% reduction in damage to fruit was recorded. Pheromone release profiles of all the dispensers were also studied under field conditions. We found that emission values >250 μg day−1 were the most suitable. This study suggests a new biodegradable dispenser capable of interfering with normal A. aurantii chemical communication. The use of mating disruption as a control method against A. aurantii is discussed.

scholarly journals El rescate de la iglesia de San José (Puerto Rico): Estudios previos a su restauración

2016 ◽  
pp. 58
Author(s):  
Beatriz Del Cueto ◽  
Agammenon G. Pantel
Keyword(s):  
Puerto Rico ◽  
San Juan ◽  
San Jose

<p>La segunda iglesia más antigua en el Nuevo Mundo está ubicada en San Juan de Puerto Rico y ha alcanzado un estado crítico de deterioro que requiere intervenciones estructurales y de conservación para segurar su permanencia. En el 2004 fue incluida en la lista de los “100 Lugares en Mayor Riesgo en el Mundo” del World Monuments Fund. Arquitectos, ingenieros estructurales, arqueólogos y técnicos en conservación realizaron una serie de estudios detallados, además de la documentación y análisis extensiva del templo entre los años 2003-2012. El presente artículo sintetiza estas investigaciones, medidas de conservación y las recomendaciones efectuadas durante este periodo.</p>

scholarly journals Monitoring and Management of Date Palm Borers by Using Light Traps

2020 ◽  
Vol 33 (2) ◽  
pp. 147-157
Author(s):  
Aqeel Alyousuf ◽  
Ali D. Shaaban ◽  
Mohammed M. Alderawii ◽  
Huda M. Alsaadie
Keyword(s):  
Date Palm ◽  
Control Method ◽  
Phoenix Dactylifera ◽  
Management Program ◽  
Management Tool ◽  
Effective Control ◽  
Light Traps ◽  
Severe Damage ◽  
Monitoring Tool ◽  
Stem Borers

Date palm borers become a serious threat to date palm plantations in Iraq, which required management program to suppress their population by using different methods; one of them is the light traps which disseminated in Basrah province. The objective of this trial is to evaluate the effectiveness of light traps as a part of pest management tool. In three years monitoring of coleopteran adults, rhinoceros beetles Oryctes spp. and longhorn date palm borer Jebusaea hammerschmidtii infesting the date palm Phoenix dactylifera were reported by using light traps in different regions of Basrah, Iraq. Due to the result of the abundance of the borers, Oryctes spp. were the most dominant and most important causing severe damage for the date palm. Four species of Oryctes (O. agamemnon, O. elegans, O. sahariensis and O. sinaicus) were recorded in Basrah date palm orchards; the seasonal activity of the species was between April and May, reaching the peaks during summer, and the populations decreased gradually till December. The overall sex ratios of all species of Oryctes spp. were male-biased except O. elegans, which had the sex ratio of 1.13 female: 1 male. Results revealed that the light traps exhibit an effective control method to suppress the adult borer’s population and as a physical control and monitoring tool of date palm stem borers.

scholarly journals Pennisetum Hydridum’s Potential for Controlling Invasive Chromolaena Odorata

2019 ◽  
Vol 11 (21) ◽  
pp. 5990
Author(s):  
Qiu-Yuan Xu ◽  
Dan Wang ◽  
Guo-Ming Quan ◽  
Jia-En Zhang ◽  
Rong-Hua Li ◽  
...  
Keyword(s):  
Invasive Plants ◽  
Competitive Ability ◽  
Invasive Plant ◽  
Control Method ◽  
Soil Nutrient ◽  
Invasive Plant Species ◽  
Chromolaena Odorata ◽  
Nutrient Contents ◽  
Morphological And Physiological Traits ◽  
Soil Nutrient Contents

The exotic Chromolaena odorata is one of the most destructive invasive plant species in South China, and hence an efficient and sustainable control method is urgent. One method, replacement control, which eliminates harmful plants by introducing another competitive plant, is being used increasingly for controlling invasive plants. To test the potential of Pennisetum hydridum to control C. odorata, a series of polyculture experiments with different proportions of the two species was conducted. Competitive indices, plant morphological and physiological traits, and soil nutrient contents were measured to test the impacts of P. hydridum on C. odorata. The presence of P. hydridum significantly suppressed growth of C. odorata, and P. hydridum was not sensitive to the presence of C. odorata. Moreover, increased root/shoot ratios of P. hydridum enhanced its underground competitive ability, and competition between the two species resulted in remarkable reductions of soil nutrient contents which would further decrease the competitiveness of the invasive C. odorata. In summary, our results suggest that P. hydridum is a prospective candidate to control C. odorata.

scholarly journals Invasive-Plant-Removal Frequency—Its Impact on Species Spread and Implications for Further Integration of Forest-Management Practices

Forests ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 502
Author(s):  
Bernabas Wolde ◽  
Pankaj Lal
Keyword(s):  
Forest Management ◽  
Plant Species ◽  
Management Practices ◽  
Invasive Plant ◽  
Control Method ◽  
Trend Test ◽  
Invasive Plant Species ◽  
Management Plans ◽  
Plant Removal ◽  
Armitage Trend Test

For a given invasive plant species and control method, effective invasive plant eradication requires regular monitoring and management. While most previous studies characterize invasive plant species, develop appropriate control methods, or prioritize species for management using aggressiveness and other considerations, few study why some forestland owners are less likely than others to regularly remove invasive plant species. Such information is useful in prioritizing and targeting forestland owners who are at greater risk for invasion, with the stands threatening adjacent forestlands. Towards this end, we surveyed 1800 forestland owners in Virginia and Texas. We use data on forestland owners’ socioeconomics and forestland features—such as acreage, forestland ownership objectives, and forest management activities—to determine how these factors affect the regularity of invasive-plant removal. For these purposes, we used the Cochran–Armitage trend test, the Cochran–Mantel–Haenszal regression, odds ratio estimates, and partition-analysis techniques. Our results suggest that female forestland owners, owners with smaller forestlands, and forestland owners without written forest-management plans are less likely than others to regularly remove invasive plant species. Forest-management activities, such as building/maintaining roads in the forestland, partially harvesting stands, and wildlife- and fisheries-improvement projects, also significantly predict a more regular invasive-plant-removal tendency. However, since these activities are potential pathways for the spread of invasive plant species, we controlled for the other significant covariates and measured the relationship between frequent practice of the given forest-management activities and having a tendency to regularly remove invasive plant species. The results suggest that forestland owners that regularly practiced the said forest-management activities have higher odds for tending to remove invasive plant species regularly, suggesting that, despite their demonstrated effort at removing invasive plant species from their forest, their management activities may be inadvertently contributing to the spread of invasive plant species. These results highlight the importance of integrating invasive-plant-removal plans with forest-management plans as well as forestland owners’ educational and outreach needs.

scholarly journals Comparative and Cost Analysis of a Novel Predictive Power Ramp Rate Control Method: A Case Study in a PV Power Plant in Puerto Rico

2021 ◽  
Vol 11 (13) ◽  
pp. 5766
Author(s):  
Juan F. Patarroyo-Montenegro ◽  
Jesus D. Vasquez-Plaza ◽  
Omar F. Rodriguez-Martinez ◽  
Yuly V. Garcia ◽  
Fabio Andrade
Keyword(s):  
Puerto Rico ◽  
Power Plant ◽  
Control Strategy ◽  
Rate Control ◽  
Control Method ◽  
Real Data ◽  
Control Methods ◽  
Ramp Rate ◽  
Proposed Model ◽  
One Year

One of the most important aspects that need to be addressed to increase solar energy penetration is the power ramp-rate control. In weak grids such as the one found in Puerto Rico, it is important to smooth power fluctuations caused by the intermittence of passing clouds. In this work, a novel power ramp-rate control strategy is proposed. Additionally, a comparison with some of the most common power ramp-rate control methods is performed using a proposed model and real solar radiation data from the Coto Laurel photovoltaic power plant located in Ponce, Puerto Rico. The proposed model was validated using one-year real data from Coto Laurel. The power ramp-rate control methods were compared in real-time simulations using the OP5700 from Opal-RT Technologies considering power ramp rate fluctuations, power ramp-rate violations, fluctuations in the state-of-charge, among other indicators. Moreover, the proposed power ramp-rate control strategy, called predictive dynamic smoothing was explained and compared. Results indicate that the predictive dynamic smoothing produced a considerably reduced Levelized Cost of Storage compared to other power ramp-rate control methods and provided a higher lifetime expectancy for lithium batteries.

scholarly journals Assessment of community support for Wolbachia-mediated population suppression as a control method for Aedes aegypti mosquitoes in a community cohort in Puerto Rico

2021 ◽  
Vol 15 (12) ◽  
pp. e0009966
Author(s):  
Liliana Sánchez-González ◽  
Laura E. Adams ◽  
Rafael Saavedra ◽  
Emma M. Little ◽  
Nicole A. Medina ◽  
...  
Keyword(s):  
Puerto Rico ◽  
Vector Control ◽  
Control Method ◽  
Animal Health ◽  
Community Support ◽  
Successful Implementation ◽  
Control Methods ◽  
Population Suppression ◽  
Male Mosquitoes

Arboviral diseases transmitted by Aedes species mosquitoes pose an increasing public health challenge in tropical regions. Wolbachia-mediated population suppression (Wolbachia suppression) is a vector control method used to reduce Aedes mosquito populations by introducing male mosquitoes infected with Wolbachia, a naturally occurring endosymbiotic bacterium. When Wolbachia-infected male mosquitoes mate with female wild mosquitoes, the resulting eggs will not hatch. Public support is vital to the successful implementation and sustainability of vector control interventions. Communities Organized to Prevent Arboviruses (COPA) is a cohort study to determine the incidence of arboviral disease in Ponce, Puerto Rico and evaluate vector control methods. Focus groups were conducted with residents of COPA communities to gather their opinion on vector control methods; during 2018–2019, adult COPA participants were interviewed regarding their views on Wolbachia suppression; and a follow-up questionnaire was conducted among a subset of participants and non-participants residing in COPA communities. We analyzed factors associated with support for this method. Among 1,528 participants in the baseline survey, median age was 37 years and 63% were female. A total of 1,032 (68%) respondents supported Wolbachia suppression. Respondents with an income of $40,000 or more were 1.34 times as likely [95% CI: 1.03, 1.37] to support Wolbachia suppression than those who earned less than $40,000 annually. Respondents who reported repellant use were 1.19 times as likely to support Wolbachia suppression [95% CI: 1.03, 1.37]. A follow-up survey in 2020 showed that most COPA participants (86%) and non-participants living in COPA communities (84%) supported Wolbachia suppression during and after an educational campaign. The most frequent questions regarding this method were related to its impact on human and animal health, and the environment. Continuous community engagement and education efforts before and during the implementation of novel vector control interventions are necessary to increase and maintain community support.

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