Early Rains Research Articles

Prediction of flash flood peak discharge in hilly areas with ungauged basins based on machine learning

ABSTRACT Peak discharge is an essential element of hydrological forecasting. Due to rapid outbreaks of flash floods in hilly areas and the lack of measured data, the fast and accurate estimation of peak discharge is crucial for flash flood hazard management. Three machine learning algorithms were applied to estimate peak discharge; this estimation was compared with the results of hydrological–hydraulic models, and the results were verified with measured watershed data. In this paper, 10 hydrological and geomorphological parameters were selected to predict the flood peak discharge in 103 watersheds in Taiyi Mountain North District. The results show that the particle swarm optimization backpropagation (PSO-BP) neural network model outperforms the BP neural network and random forest regression in prediction performance. PSO-BP has a lower mean absolute error (2.51%), root mean square error (3.74%), and mean absolute percentage error (2.74%) than the other models, which indicates that PSO-BP has high prediction accuracy. Importance analysis revealed that rainfall, early impact rainfall, catchment area, and rain intensity are the key input parameters of PSO-BP. The proposed method was confirmed to be a fast and relatively accurate algorithm for estimating the peak discharge of flash floods in ungauged basins.

Climate Change Perception and Vulnerability Assessment of the Farming Communities in the Southwest Parts of Ethiopia

This study assesses the perceptions and vulnerability of the farming communities to climate change in the southwestern parts of Ethiopia. Climate change vulnerability assessment is a prerequisite to designing climate change adaptation strategies. A multistage cluster sampling technique was used to select four of the six zones from the southwestern parts of Oromia. Close-ended and open-ended questionnaires were used to assess household perceptions of climate change and the degree of vulnerability to climate change by using five household capitals: natural, social, financial, physical, and human capital. Data were collected from 442 households in 4 districts: Jimma Arjo, Bako Tibe, Chewaka, and Sekoru. The vulnerability of the farming communities was assessed using the households’ livelihood vulnerability index. A total of forty indicators from five capitals were applied to calculate household livelihood vulnerability to climate change. Household perceptions of climate change had a statistically significant relationship with changes in rainfall pattern (75.6%, p < 0.001), temperature pattern (69.7%, p < 0.001), drought (41.6%, p = 0.016), flood (44.1%, p = 0.000), and occurrence of early (53.2%, p < 0.001) and late rain (55.9%, p < 0.001). The results show that households in the Sekoru district were the most vulnerable (0.61), while households in the Jimma Arjo district were less vulnerable (0.47) to the effect of climate change. Household vulnerability to climate change is mainly related to the occurrence of drought, lack of much-needed infrastructure facilities, and weak institutional support. Links with financial organizations are also lacking in the household. The findings of this study will help policymakers to address the impact of climate change. To support disaster risk management on the one hand and increase the resilience of vulnerable societies to climate change on the other, we recommend a detailed assessment of the remaining districts of the region.

Factors affecting development of disorders expressed after storage of ‘Gala’ apple fruit

This study investigated factors influencing susceptibility and development of physiological disorders and decay expressed after long-term storage in ‘Gala’ apple fruit (Malus domestica Borkh.). Five experiments were performed over ten production years with fruit from two environmentally different orchard locations in a humid subtropical climate at 990 m (warmer) and 1415 m above sea level. Fruit were harvested at two maturity stages (early and advanced), treated or not treated with 1-methylcyclopropene (1-MCP) and stored at 0.5 °C or 2 °C in a controlled atmosphere (CA, 1.5 kPa O2 and 2.5 kPa CO2), for 240 d plus 7 d shelf life. In one experiment, fruit were stored in CA with CO2 concentrations of 1.5 or 3 kPa. The relationship between fruit mineral composition and physiological disorders was assessed in one production year. Flesh browning (FB) was the predominant disorder, followed by decay, cracking, and lenticel breakdown-wet (LB-wet). The average severity index of lenticel breakdown-dry (LB-dry), leather blotch and bitter pit were low and variable across production years. The FB index was lowest in fruit produced at the colder orchard location, early harvest, treatment with 1-MCP, and storage at 2 °C. These factors also influenced fruit softening after storage. The major source of variance of the FB index in order of decreasing contribution were harvest maturity, production year, orchard location, 1-MCP and storage temperature. Production year variability of FB index correlated positively with early summer rain and negatively with early spring temperature. A weak positive correlation was also found between FB index and fruit K+Mg/Ca ratio. Higher CA CO2 concentration increased FB in fruit stored at 0.5 °C but not at 2 °C. The same factors affected decay, cracking and LB-wet disorder similarly as for FB, except that decay and cracking were not consistently affected by storage temperature, and decay and LB-wet were not impacted by 1-MCP. Storage temperature had the most influence on the variance of LB-wet. LB-dry was highest in late harvest fruit and, in the production year with the highest index, in fruit stored at 0.5 °C. Leather blotch was highest in early harvest fruit and in fruit stored at 0.5 °C. 1-MCP treatment did not affect disorders other than FB and cracking. These results suggest that interactions among harvest and postharvest factors influence the development of ‘Gala’ FB and other disorders and indicate a possible relationship of chilling in FB development. The information may be useful for implementing practical strategies to reduce the development of these postharvest disorders in ‘Gala’ apple fruit.

Phenophase-based comparison of field observations to satellite-based actual evaporation estimates of a natural woodland: miombo woodland, southern Africa

Abstract. The trend and magnitude of actual evaporation across the phenophases of miombo woodlands are unknown. This is because estimating evaporation in African woodland ecosystems continues to be a challenge, as flux observation towers are scant if not completely lacking in most ecosystems. Furthermore, significant phenophase-based discrepancies in both trend and magnitude exist among the satellite-based evaporation estimates (i.e. Global Land Evaporation Amsterdam Model (GLEAM), moderate resolution imaging spectroradiometer (MODIS), operational simplified surface energy balance (SSEBop), and water productivity through open-access remotely sensed derived data (WaPOR)), making it difficult to ascertain which of the estimates are close to field conditions. Despite the many limitations with estimation of evaporation in woodlands, the development and application of the distributed temperature system (DTS) is providing deepened insights and improved accuracy in woodland energy partitioning for evaporation assessment. In this study, the Bowen ratio distributed temperature sensing (BR-DTS) approach is used to partition available energy and estimate actual evaporation across three canopy phenophases of the miombo woodland, covering the entire 2021 dry season (May–October) and early rain season (November–December) at a representative site in Mpika in Zambia, southern Africa. To complement the field experiment, four satellite-based evaporation estimates are compared to the field observations. Our results show that actual evaporation of the miombo woodland appears to follow the trend of the net radiation, with the lowest values observed during the phenophase with the lowest net radiation in the cool dry season and the highest values during the phenophase with peak net radiation in the early rainy season. It appears the continued transpiration during the driest period in the dormant phenophase (with lowest canopy cover and photosynthetic activities) may be influenced by the species-dependent adapted physiological attributes such as access to moisture in deep soils (i.e. due to deep rooting), plant water storage, and the simultaneous leaf fall and leaf flush among miombo plants. Of the four satellite-based evaporation estimates, only the WaPOR has a similar trend to the field observations across the three phenophases. However, all four satellite-based estimates underestimate the actual evaporation during the dormant and green-up phenophases. Large coefficients of variation in actual evaporation estimates among the satellite-based estimates exist in the dormant and green-up phenophases and are indicative of the difficulty in estimating actual evaporation in these phenophases. The differences between field observations and satellite-based evaporation estimates can be attributed to the model structure, processes, and inputs.

Quick Curing Mechanisms for All-Season Paints and Renders.

Paints and coatings are required to quickly cure under a broad variety of environmental conditions and deliver solid long-term performance. Achieving a balance during all seasons between quick curing of a coating film, i.e., early rain resistance, while maintaining sufficient workability and open time for an optimized aesthetic appearance is a challenge for the architectural coatings industry. This article describes how the colloidal physics differs between the current standard mechanism to achieve early rain resistance by inhibited coagulants in winter paints and a new mechanism that provides all-season paints. A combination of advanced physical characterization methods, such as electrophoretic mobility, dynamic light scattering and confocal laser scanning microscopy, in combination with application tests, is used to provide a comprehensive mechanism of the early rain resistance achieved by such paints. In addition, it is shown that this new system can be transferred to wood coatings and organic renders. The key finding of this article is that all-season paints combining early rain resistance at cold and damp conditions with open time at high temperatures and dry conditions rely on fast paint film formation with high early integrity rather than coagulants triggered by base evaporation.

Chemometric and risk assessment of nitrogen composition of atmospheric rainwater from diverse surfaces in Rivers State, Nigeria.

Organic and inorganic nitrogen ions in the environment play important role across environmental matrices. Rainwater samples collected from ambient and different roofing surfaces (zinc, aluminium, asbestos and stone-coated roofing sheets) from selected locations at Ogale, Rumuodomaya/Rumuodome, Diobu and Chokocho within Rivers State, Niger Delta, Nigeria, from April to June, July to August and September to October depicting three regiments of early, mid and late rains. The samples were analysed for Kjeldahl nitrogen, ammonium, nitrate and nitrite using APHA methodology. Quantitative assessment showed that Kjeldahl nitrogen were in range of 0.11 to 28.05mg/L; ammonium 0.50 to 20.22mg/L, nitrate from 0.12 to 22.69mg/L and nitrite from 0.15 to 3.90mg/L. Parameters decreased from early to late rain, which can be attributed to rain dilution factor potential, wind pattern and emission from anthropogenic sources that influenced the rainwater quality across surfaces. Nitrogen results showed that dry and wet deposition has great impact; atmospheric aerosols and biogeochemical interactions can affect water quality. Monthly variation showed that Ogale had high regression compared to other locations due to close proximity to oil and gas emission and marine contribution. Neutralization factor showed that nitrate-nitrite compounds have strong correlation with ammonium ion. Non-carcinogenic risk assessment using US EPA model showed hazard index less than one (1), thus no associated health effect of nitrate and nitrite in rainwater. In conclusion, it is evident that nitrate/nitrite levels and other nitrogen derivatives in rainwater in crude oil-producing Niger Delta and its continuous consumption can cause negative health outcome.

Chemometrics, health risk assessment and probable sources of soluble total petroleum hydrocarbons in atmospheric rainwater, Rivers State, Nigeria

Total petroleum hydrocarbons (TPHs)—(aliphatic and aromatic) were analysed for in atmospheric rainwater between April–June; July–August; September–October depicting early, mid, late rain of 2019. Sampling at Rumuodomaya/Rumuodome and Ogale in Rivers State using basins fastened to a Table 2M above ground and 120 M from high features, Rainwater was analysed after treatment using Agilent GC-FID. Results show cumulative TPHs at R/R were 56.6551 mg/L, 39.5201 mg/L and 7.2283 mg/L, Ogale: 9.1217 mg/L, 59.4923 mg/L and 21.9825 mg/L. Aliphatic hydrocarbons: C5–C8 were < 1, low contamination, other carbon aggregates (C9–C16, C17–C35, and C36–C40) indicate high contamination. Chemometric assessment showed high contamination. TPHs aggregates at Rumuodomaya/Rumuodome were–C8–C11 (1.034 and 1.005) early rain, C18–C25 and C26–C33 has Carbon preference index of 1.287 and 1.630 (mid-rain), C26–C33 has CPI of 1.288 (late-rain), Ogale area, C26–C33 has CPI of 1.732 (early-rain), mid-rain C8–C11 (2.768) and C12–C17 (5.368). Pristane/phytane ratio indicated biogenic and pyrogenic sources. Average carbon length of TPHs for odd n-alkanes were C9–C11 (9.446) and C35–C39 (38.980), C9–C11(10.238), C35–C39 (36.510); C9–C11 (10.240) and C35–C39 (36.934). Average daily intake depicted possible health issues for children and adults as hazard index > 1 for aromatics.

Growing Quinoa in Washington State

Washington State University researchers have been exploring the feasibility of growing quinoa in the Pacific Northwest. In their effort to develop new varieties adapted to Washington State, they focused on key traits for improvement and are close to releasing their first varieties that address and improve upon one or more of these characteristics. A new crop to most farmers in Washington, quinoa presents significant production challenges, particularly with susceptibility to heat in the central and eastern parts of the state, susceptibility to pre‐harvest sprouting due to early rains in western Washington, and susceptibility to weed pressure almost everywhere. Earn 0.5 CEUs in Crop Management by taking the quiz for the article at https://web.sciencesocieties.org/Learning‐Center/Courses.

Collaborative agent-based modeling for managing shrub encroachment in an Afroalpine grassland

We co-designed an agent-based model of an Afroalpine grassland in Ethiopia that is experiencing unwanted shrub encroachment. The goal was to enable managers of a community conservation area to better understand the drivers of shrub encroachment and to test possible management actions for controlling shrubs. Due to limited site-specific data, we parameterized this model using insights from published literature, remote sensing, and expert opinion from scientists and local managers. We therefore sought to explore potential future scenarios rather than make highly accurate predictions, focusing on facilitating discussions and learning among the diverse co-management team. We evaluated three social-ecological scenarios with our model, examining: (1) the impact of changing precipitation regimes on vegetation, (2) whether changing the frequency of guassa grass harvests would improve the long-term sustainability of the grassland, and (3) whether the combination of grass harvest and shrub removal would affect shrub encroachment. We found that the model was highly sensitive to the amount of grass harvested each year for local use. Our results indicate that the guassa grass was more resilient than shrubs during persistent dry climatic conditions, whereas a reduction in only the early spring rains (known as the “belg”) resulted in considerable loss of grass biomass. While our modeling results lacked the quantitative specificity desired by managers, participants in the collaborative modeling process learned new approaches to planning and management of the conservation area and expanded their knowledge of the ecological complexity of the system. Several participants used the model as a boundary object, interpreting it in ways that reinforced their cultural values and goals for the conservation area. Our work highlights the lack of detailed scientific knowledge of Afroalpine ecosystems, and urges managers to reconnect with traditional ecological management of the conservation area in their pursuit of shrub encroachment solutions. The decline or absence of the belg rains is becoming increasingly common in the Ethiopian highlands, and our results underscore the need for more widespread understanding of how this changing climatic regime impacts local environmental management. This work lays a foundation for social-ecological research to improve both understanding and management of these highly threatened ecosystems.

Livelihood of salt farmers in the context of environmental changes in Can Gio district, Vietnam

Agricultural production is highly dependent on the environment and sensitive to environmental changes. During the past time, the changes in natural and socio-economic factors have strongly affected salt production. Thus, salt farmers in Can Gio, Ho Chi Minh City have put great effort into implementing various solutions to overcome the difficulties to maintain production, secure income, stabilize life and preserve traditional occupation. To have a full and systematic view on this issue, a study on the livelihoods of salt farmers in the context of environmental changes was carried out. The study used the social survey method with a sample size of 106 salt-producing households in Can Gio district. Data collection tool is a structured questionnaire and data analysis methods are descriptive and inferential statistics. Results show that salt production is a livelihood that is easily vulnerable to changes in natural and socio-economic factors. As for the natural factors, early and erratic rains are the main risk for salt production. Regarding the socio-economic factors, unstable markets, falling selling prices and increasing production costs bring many risks to salt farmers. They perceive environmental changes and their impacts on their livelihoods. The current livelihood capacities of farmers including financial, technical and institutional capacities for salt production are not high. Solutions implemented locally to deal with negative environmental impacts include adjusting production inputs, diversifying livelihoods and connecting salt production areas with consumption markets.

The Establishment and Spread of a Newly Introduced Begomovirus in a Dry Tropical Environment Using Tomato Yellow Leaf Curl Virus as a Case Study.

Early detection of tomato yellow leaf curl virus (TYLCV) in a previously unaffected tomato production district in Australia allowed its spread to be evaluated spatially and temporally. The population dynamics of the TYLCV vector, Bemisia argentifolii (silverleaf whitefly, SLW), were also evaluated. The district is a dry tropical environment with a clear break to commercial production during the summer wet season. The incidence of TYLCV within crops and its prevalence through the district was influenced by weather, location, vector movements, and the use of Ty-1 virus-resistant hybrids. Rainfall had an important influence, with late summer and early autumn rain suppressing the levels of SLW and, by contrast, a dry summer supporting faster population growth. The use of Ty-1 hybrids appears to have reduced the incidence of TYLCV in this district. There was limited use of Ty-1 hybrids during 2013, and by season end, crops had moderate levels of SLW and high virus incidence. The 2015 and early 2016 season had high SLW populations, but TYLCV incidence was lower than in 2013, possibly due to the widespread adoption of the Ty-1 hybrids reducing virus spread. This study provides valuable epidemiology data for future incursions of begomoviruses, and other viruses spread by SLW.

Interactions of Undescribed Drilus Beetle Larvae with Pestiferous Limicolaria flammea (Gastropoda: Achatinidae): Are There Prospects for Biocontrol?

The garden snail, Limicolaria flammea is a seasonal pest of several horticultural crops in most of the agroecological areas in Nigeria. The level of damage to crops is especially enormous in the South because of its ability to feed on different crops and the timing of abundance, the early rain season, which usually coincide with onset of rain-fed crop production which expose seedlings and grown-up crop plants to serious damage. In this study, we recorded occurrence data of Limicolaria flammea in okra, carrot, sweet potato, lettuce and maize within a single multi-crop organic farm in order to understand its food preference. Activities of the predatory beetle larvae, Drilus sp was observed within the environment. The appearance of the larvae was described and its interaction with L. flammea was studied to generate some data on the proportions of snail mortality caused by Drilus sp and other mortality factors that naturally regulate the population dynamics of L. flammea within the environment. There was no statistically significant difference in the average number of snails recorded in the different cropping fields [F (4,15) =1.369, P=0.291]. The activities of Drilus larvae against L. flammea was higher in okra and carrot plots as snail mortality due to the larvae attack were significantly higher compared to what was recorded in other crop plots [F (4, 30) =3.998, P=0.01].The Drilus larvae predate on L. flammea by appertural entry, biting through the soft tissues around the mantle to gain entrance and moult into instar larvae within the snail shell in 15-20 days, leaving its exuviae behind in the shell in all the specimens observed (n=40). The Drilus species being reported in this study is morphologically distinct from other described species in available literature. The study suggested that the Drilus species is less known and there are potentials that the species could be useful in inundative biocontrol approaches for the management of pestiferous gastropod populations.

SEASONAL VARIATIONS IN THE CHEMICAL COMPOSITION OF GRASSES HARVESTED FROM THE NATURAL PASTURE IN OGUN STATE SOUTH-WESTERN NIGERIA

The research was carried was carried out to evaluate the chemical composition of the dominant grasses harvested from the natural pasture in selected villages in Ogun State, South-western Nigeria at different seasons. The study was carried out using a 4 × 6 factorial arrangement comprising four seasons (early rain, late rain, early dry and late dry) at six locations (Afami, Atokun, Ibooro, Ileniku, Ipaaya, and Okerori). Results showed that the crude protein (CP) content significantly (p&lt;0.05) varied from 5.56 % for Okerori to 7.34 % for Ibooro and the grasses harvested at Afami had the highest (72.75 %) neutral detergent fibre (NDF) values with the least (68.75 %) value recorded for Okerori, while the acid detergent fibre (ADF) values ranged from 41.00 % for Atokun to 48.25 % for Okerori. Also, CP value as affected by the season ranged from 4.23 % for late rainy to 9.44 % for the early rainy season and NDF values from 67.33% for late dry to 72.33 % for late rainy season while the early dry season had the highest value (48.00 %) for ADF with the least value (40.33 %) was recorded for the early rainy season. The phosphorus (P) value was highest at Ipaaya (2.99 g/kg) with the least value observed at Okerori (1.62 g/kg). The value for calcium ranged from 2.55 g/kg at Afami to 6.59 g/kg at Okerori. The P value of grasses as affected by seasons ranged from 1.46 g/kg for early dry to 2.66 g/kg for early rainy seasons.

Li Ma, Religious Entrepreneurism in China's Urban House Churches: The Rise and Fall of Early Rain Reformed Presbyterian Church

Li Ma, <i>Religious Entrepreneurism in China's Urban House Churches: The Rise and Fall of Early Rain Reformed Presbyterian Church</i>

Interannual variability of monsoon onset and withdrawal in Bangladesh

AbstractThis research investigates the interannual variability of monsoon onset and withdrawal in Bangladesh, both of which are major climate features shaping multiple societal activities. There is considerable research on the monsoon timing in South Asia, but with much less focus on Bangladesh. We applied a local monsoon onset and withdrawal definition to observations and the latest‐generation high‐resolution gridded precipitation data from the Climate Hazards Center for the period 1981 through 2018. We analyzed the interannual variability in monsoon timing in Bangladesh and its teleconnection with the sea surface temperature anomalies (SSTA) over the Pacific Ocean (El Niño Southern Oscillation, ENSO) and the Indian Ocean (IO). The monsoon starts with early significant rains in northeast Bangladesh and propagates westward, and a similar pattern is observed for withdrawal, which tends to be more homogeneous in time and space. A high spatial and temporal variability in monsoon onset and withdrawal is observed in Bangladesh, with a within‐country average range of around 1 month despite it being a country of relatively small size. The association between monsoon onset and withdrawal and ENSO and IO is addressed at the country and regional level by analyzing composites for different ENSO and IO phases and associated atmospheric circulation and moisture transport. A similar association between monsoon onset and ENSO and IO phases was found, with generally earlier (later) onset dates during the negative (positive) phase of ENSO and IO. Monsoon withdrawal shows a clearer association with ENSO, with earlier (later) dates during the positive (negative) phase. Monsoon withdrawal is earlier during the negative IO phase. SSTA‐induced anomalies in circulation and moisture transport contribute to anomalies in monsoon timing. Results suggest both ENSO and IOD can be potentially used as sources of predictability of monsoon onset and withdrawal over specific regions of Bangladesh.

Economics of chemical and non-chemical approaches for induction of early flowering in mango cv. Alphonso

Mango cv. Alphonso is established on more than 90 per cent of area in Konkan region of Maharashtra. Early flowering is for early harvest which assures premium rate in market. In recent years climatic aberrations such as delayed rains especially during initiation of flowering badly affected the performance of Alphonso. The delayed flowering further delay fruit development and harvesting. The late harvested fruits often trapped in early rains and fetches low market price. An attempt was made to estimate benefit ratio and net returns of various non-chemical approaches for mango cv. Alphonso in relation to early induction of flowering which lead to early harvesting to earn lucrative market price. The experiment entitled “Economics of chemical and non-chemical approaches for induction of early flowering in mango cv. Alphonso” which was conducted at college of Horticulture, Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli during the year 2018-19 and 2019-20. Experiment was laid out in randomized block design with seven treatments viz., T1- removal of new shoots, T2- removal of old shoots below new, T3- foliar spray of paclobutrazol @ 500 ppm, T4- foliar spray of paclobutrazol @ 1000 ppm, T5- foliar spray of ortho-phosphoric acid @ 0.5 %, T6- foliar spray of ortho-phosphoric acid @ 1 % and T7- control which were replicated at thrice. From the pooled analysis, early induction of flowering was rapid in T1(35.83 days) and had maximum yield (6.19 t/ha), higher gross return (Rs.309657), maximum net profit (Rs.217781.70) and highest B:C ratio (3.37) which was followed by T2 (3.34), T3 (2.99) and T4 (2.75). The minimum yield (2.90 t/ha), gross return (Rs. 124860), minimum net profit (Rs. 65509.20)with minimum B:C ratio were found in control.

Genotype × environment analysis of cowpea grain production in the forest and derived savannah cultivation ecologies

Differential performance of genotypes in different cultivation environments has remained a challenge to farmers and plant breeders, the emphasis being the selection of high yielding and stable genotypes, across similar ecologies. A set of nine cowpea genotypes were cultivated in Ago-Iwoye and Ayetoro, two locations representing high and moderate moisture zones. Plantings were done with the early and late season rains in Ago-Iwoye and mid-late season rains of Ayetoro. Statistical analysis was done to understand genotype reaction to the different environments and the plant and environment factors mediating the performance. The Additive Main Effect and Multiplicative Interaction (AMMI) model captured 61.30% of the total sum of squares (TSS). The main effects: genotype (G) environment (E) and their interaction (GxE) were significant with the largest contribution of 28.70% by the environment while the interaction and genotype fractionscaptured 20.20% and 12.40%, respectively. The percentage contribution of the main effects and GxE to total sum of squares (TSS) for traits was not consistent. The Genotype plus Genotype-by-Environment (GGE) analysis summarized 91.30% of the variation in genotype performance across environment. The cultivation environments were separated into two, with IT 95M 118 as the vertex genotype in the Ayetoro while TVU 8905 was the topmost genotype in Ago-Iwoye. The two genotypes recorded the highest grain weight per plant (GWPP) but were also the most unstable The stable genotypes IT 95M 120 and IT 86 D 716 flowered relatively late compared to others, are taller, had higher vegetative score and are low grain producers.&#x0D; Key words: AMMI, drought, GGE, stability, Vigna unguiculata

The enigmatic Rothschild's Swift (Cypseloides rothschildi): Natural history, distribution, and seasonality

Rothschild's Swift (Cypseloides rothschildi) is among the least known South American swifts. Here we clarify its distribution and seasonality, and provide detailed natural history data and breeding information. We compiled 197 records of Rothschild's Swifts (museum specimens, citizen science initiatives, literature, and field observations) from Argentina and Bolivia; most from the breeding season (Oct–Mar, 177 records; 44 documented), a few thought to be on migration (Apr and Sep, 15 records; 3 documented), and fewer during the nonbreeding period (May–Aug, 5 records; 1 documented) with no records from July/August. Rothschild's Swifts are migratory, but the wintering quarters remain unknown. The distribution during the breeding season is broadly overlapping with the Austral Yungas of Argentina and Bolivia, with sparse records in Andean and extra-Andean ranges with forested and non-forested waterfalls. Our breeding distribution model indicated high presence probabilities in the Austral Yungas of Bolivia and Argentina. The breeding season during the austral spring and summer (late Oct/mid-Nov to mid-Mar/early Apr in northwest Argentina) began roughly with the early rains as in other Neotropical swifts. Our data from 8 breeding sites and from 8 nests that we studied in northwest Argentina regarding nest placement (near waterfalls), nest features (moss or moss and mud cups), eggs (single and white), and on the protracted development of Rothschild's Swift nestlings (∼55–60 d) and the sequence of plumage acquisition and behavior were coincidental with what is known from other Cypseloides. We provide behavioral information from a temporarily captive individual, which provided the first sound recordings of nestling/fledgling vocalizations of Rothschild's Swift—presumably the first available for any Cypseloides. It is unclear whether these vocalizations, recorded in captivity, represent developmental precursors of adult sounds or begging calls.

Spatiotemporal Variations in Water Flow and Quality in the Sanyang Wetland, China: Implications for Environmental Restoration

Spatiotemporal modeling of wetland environments’ hydrodynamics and water quality characteristics is key to understanding and managing these ecologically important areas’ physical and environmental properties. We developed a two-dimensional numerical model based on the MIKE 21 module to analyze flow and pollution dynamics in the island-dominated Sanyang wetland of eastern China. Three simulation periods representing annual precipitation cycles were used to model freshwater discharge and water quality in the wetland. The results showed that the flow velocity in the study area had hydrodynamic characteristics typical of such a setting, with an average monthly flow velocity ranging from 0.01 to 0.04 m/s, contributing to an increased risk of serious eutrophication. The water quality problems (represented by ammonia nitrogen, NH3-N, and total phosphorus, TP, levels) peaked during the early summer peak rain season, followed by a gradual decline during a later flood period and the lowest values during the fall/winter dry period. Moreover, the spatial distribution of NH3-N and TP levels decreased from northwest to east, reflecting the influence of a highly polluted source. Our results provide a useful context for restoration efforts in the Sanyang wetland and other similar areas.

Effect of interspecific competition among whiteflies (Homoptera: Aleyrodidae) on crops and ornamental plants in Southwestern Nigeria

Whiteflies that are pests of many crops and ornamental plants produce migratory forms during dense populations with different species sharing the same host plant. Fields surveys of these pests were conducted from 8 sampling sites within the five states (Lagos, Oyo, Osun, Ekiti and Ondo states) of Southwestern Nigeria during 2016 and 2019 to investigate the effects of interspecific competition among whiteflies on plants in the region. This survey was carried out in both wet and dry seasons. Whiteflies were collected on crops and ornamental plants in the sampling sites within the mangrove forest, rainforest and the derived savannah zones in the region. Interspecific competition was observed between four species Aleurodicus dispersus, A cocois, Aleurocanthus woglumi and Bemisia tabaci. The species population of whiteflies was analyzed using the Paleontological statistics software package (PAST) and nonparametric t-test was conducted to analyse the sharing of the host surface among species. The results obtained showed that the interspecific competition among species of whiteflies in the region is most during early rain season and yielded less whiteflies infestation and abundance at underside of plant leaves, and as well supported high number of the pest on upper leaf surfaces. The integrative analysis of the consequences of interspecific competition could provide justification for predicting species exclusion resulting into whitefly invasions of upper leaf surfaces as their new ecological niche.