Malena Torres-Ulloa

Ms. Malena Torres-Ulloa

orcid

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 May 2024 in Frontiers in Climate
Verified
Journal Article
Open access
DPDiego Portalanza
Diego Portalanza
MTMalena Torres-Ulloa
Malena Torres-Ulloa
FRFlavia Rosso
Flavia Rosso
CZCristian Felipe Zuluaga
Cristian Felipe Zuluaga
ADAngelica Durigon
Angelica Durigon
SFSimone Ferraz
Simone Ferraz
Ecuador, a country with distinct coastal (CO), highland (HL), and Amazon (AM) regions that are characterized by unique climatic, ecological, and socio-economic features is highly vulnerable to climate change. This study focuses on these three regions, highlighting their individual importance in the broader context of Ecuador's climate vulnerability. Utilizing dynamically downscaled data from the Regional Climate Model (RCM), we generated precipitation and air temperature projections for the period 2070–2099 under three different climate change scenarios. We indicate projected temperature increases across all three regions: mean temperature increases for the CO, HL and AM regions are of 1.35, 1.55, and 1.21°C, respectively. Each year, the largest temperature increases are predicted for the third quarter (June–August), with the smallest increases predicted for the last quarter (December–February). Precipitation patterns show varied changes, with CO exhibiting a positive mean daily change, in contrast to a mean negative change in the AM region. These region-specific projections underscore the differential impacts of climate change within Ecuador and highlight the necessity for tailored adaptation measures. The study's novel approach, focusing on distinct regional impacts within a single nation, offers valuable insights for policymakers, aiding in the development of effective, region-specific climate change mitigation and adaptation strategies. This targeted approach is crucial to address unique challenges faced by different regions, thereby supporting national resilience strategies.

1 November 2022 in Agriculture
Verified
Journal Article
Open access
PDF file
DPDiego Portalanza
Diego Portalanza
Finbarr HorganFinbarr Horgan
Finbarr Horgan
Valeria PolhmannValeria Polhmann
Valeria Polhmann
SCSantiago Vianna Cuadra
Santiago Vianna Cuadra
MTMalena Torres-Ulloa
Malena Torres-Ulloa
ADAngelica Durigon
Angelica Durigon
Rice (Oryza sativa L.) is the main staple food of more than 50% of the world’s population. However, global production may need to increase by more than 70% before 2050 to meet global food requirements despite increasing challenges due to environmental degradation, a changing climate, and extreme weather events. Rice production in Ecuador, mainly concentrated in lowland tropical plains, declined in recent years. In this paper, we aim to calibrate and validate Kobayashi’s ‘Very Simple Model’ (VSM) and, using downscaled corrected climate data, to quantify the potential impact of climate change on rice yields for Ecuador’s two main rice-growing provinces. The negative impact is expected to be highest (up to −67%; 2946 tons) under the Representative Concentration Pathway (RCP) 8.5, with a lower impact under RCP 2.6 (−36%; 1650 tons) yield reduction in the Guayas province. A positive impact on yield is predicted for Los Ríos Province (up to 9%; 161 tons) under RCP 8.5. These different impacts indicate the utility of fine-scale analyses using simple models to make predictions that are relevant to regional production scenarios. Our prediction of possible changes in rice productivity can help policymakers define a variety of requirements to meet the demands of a changing climate.

27 December 2022 in Recycling
Verified
Journal Article
Open access
PDF file
MSMartha Sumba
Martha Sumba
EAEduardo I. Alava
Eduardo I. Alava
LGLuis Galarza
Luis Galarza
Johana Ortiz-UlloaJohana Ortiz-Ulloa
Johana Ortiz-Ulloa
ECEduardo Jose Chica
Eduardo Jose Chica
MTMalena Torres-Ulloa
Malena Torres-Ulloa
Hermetia illucens is an important species for waste management and the circular economy. The aim of this study was to analyze the effects of Trichoderma reesei C2A and Pleurotus sp. as pretreatments of brewer spent grain (BSG). BSG was inoculated with fungal solution or distilled water (control). After seven days, this was used for H. illucens larvae cultivation. At the end of bioconversion process, parameters of substrate reduction and H. illucens larval development were evaluated. Chemical properties of BSG, frass and larvae were also analyzed. With T. reesei C2A pretreatment, highest substrate reduction (46.3 ± 0.9%) was achieved, but larval growth rate was lower (1.0 ± 0.1 mg/d) than that of control (2.8 ± 0.2 mg/d). Larvae of Pleurotus sp. pretreatment had limited development, reflected in their negative growth rate (−0.6 ± 0.2 mg/d). In conclusion, cultivation of H. illucens larvae (six day old) on BSG pretreated with Pleurotus sp. is not recommended. On the other hand, T. reesei C2A pretreatment enhance BSG reduction, and its potential use for lignocellulosic waste management should be more explored.

2 February 2026 in Environmental and Sustainability Indicators
Verified
Journal Article
Open access
MTMalena Torres-Ulloa
Malena Torres-Ulloa
VVVladimir Verner
Vladimir Verner
RERamón Espinel
Ramón Espinel
DPDiego Portalanza
Diego Portalanza
EÁEduardo Álava
Eduardo Álava
PDPatrick Van Damme
Patrick Van Damme

15 January 2026 in Recycling
Verified
Journal Article
Open access
PDF file
MSMartha Sumba
Martha Sumba
CACarlos Amador
Carlos Amador
DPDiego Portalanza
Diego Portalanza
JAJorge Amaya
Jorge Amaya
OROmar Ruiz-Barzola
Omar Ruiz-Barzola
EAEduardo I. Alava
Eduardo I. Alava
The growing generation of organic solid waste from small-scale agriculture poses major environmental challenges in developing countries like Ecuador, where rural areas often lack waste management infrastructure. Residues from livestock rearing and traditional brewing such as poultry manure (PM), bovine manure (BM), and barley by-product (BB) are often discarded untreated. This study evaluated the bioconversion potential of Hermetia illucens (black soldier fly larvae (BSFL), using a local Ecuadorian strain reared on these substrates under natural conditions and three feeding rates (50, 100, and 150 mg·larva−1·day−1). Larval growth and process efficiency were analyzed on a dry-matter basis. Both substrate and feeding rate significantly influenced performance (p < 0.05). PM and BB produced the highest larval dry weights (37.4 and 35.9 mg, respectively) at 100 mg·larva−1·day−1, with development completed in 35 days. BM-fed larvae reached only 17.6 mg and required up to 91 days. Bioconversion peaked at 4.6% (PM100) and 4.2% (BB50), while all BM treatments showed very low efficiency (<0.8%). Waste reduction was highest in BB100 (52.9%) and PM100 (43.5%). These results demonstrate the potential of BSFL as a biological treatment option for rural organic waste streams; however, performance strongly depended on substrate quality and feeding rate, indicating that not all locally available residues are equally suitable for larval bioconversion.