Number Of Wet Months Research Articles

Agroclimate zone analysis for the suitability of rice plantation in Donggala District

As one of the supporting districts for regional food security, the productivity of food crops in Donggala Regency needs to be continuously improved. Climate type information is closely related to business development in agriculture, especially rice plants. This study aims to determine the type and distribution of agro-climatic zones for rice land suitability in Donggala Regency. This study uses the climate classification method according to Oldeman by calculating the number of wet months and dry months for one year which is then mapped using the Inverse Distance Weighted (IDW) method. The data used in this study are rainfall data for 10 years (2011-2020) from 15 points of BMKG rain observation posts as well as the Planting Calendar for rice plants from the Ministry of Agriculture. The results showed that Donggala Regency has 3 Oldeman climate types, namely type A in Rio Pakava District with the suitability of continuous rice cultivation but low production, B in Banawa Selatan and Sojol Districts with the suitability of continuous rice planting with high production when harvested during drought season. Type E in the Districts of Central Banawa, Banawa, Tanantovea, Labuan, Sindue, Sindue Tobata, Sindue Tombusabora, Balaesang, Balaesang Tanjung, North Sojol and Dampelas which is too dry, so that only one planting period of crops is possible. In areas with climate type E it is recommended to optimize irrigation to meet the water needs of rice plants. The agro-climate zone map made using the IDW interpolation method can describe the distribution of climate types as a whole, especially in areas where there are no rain gauge posts such as in Pinembani District.

Assessing Vulnerability and Population Exposed to Drought in Various Climatic Regions of Northeastern Iran

Abstract The motivations of this research are the continuation and intensification of drought effects on various socioeconomic sectors and the observation of few studies and no coordinated efforts to provide a compatible framework for drought risk management in different economic sectors and population groups of the study region. Present research was carried out to assess the vulnerability and population exposed to drought in Khorasan Razavi Province. Meteorological datasets for the years 1950–2020; drought indices including self-calibrating Palmer (scPDSI), standardized precipitation (SPI), and standardized precipitation evapotranspiration (SPEI); population and livestock density indicators; agricultural lands; water stress; and socioeconomic and infrastructural factors have been used. Results indicate that dry and wet periods were estimated to be more intense by SPEI in all studied stations; also, a significant difference was observed between the results of the SPI and SPEI indices in determining the long dry and wet periods. The highest variation between the occurrence of dry and wet periods was estimated using SPEI, which could be related to seasonal fluctuations of temperature and computational evapotranspiration. Although no significant correlation was observed between used indices to identify the number of wet months, a significant positive correlation exists between the numbers of dry months estimated by those. Drought risk analysis demonstrated that the central and southern parts of the province are exposed to very severe drought while the northern and northeastern parts of the area are more inclined to severe drought. The highest class of drought exposure is observed in the southern, central, and eastern regions of the province, so they represent the high-risk category of drought.

Analysis of Coconut (Cocos Nucifera L) Commodities Based on Land Suitability in the Pining District of Gayo Lues

Using a survey method, this study aimed to examine the characteristics of the land and the direction of land usage for cultivating coconuts. The land's features are described in a land map created from the overlapping findings of each land map unit, which serves as a foundation for additional study to fit the environment for growing coconut plants. According to the results of the analytics and planning of the land conservation of coconut crops in Gayo Luwes, for the crops to survive, it is vital to pay attention to soil characteristics such as temperature, rainfall, soil type, and the number of wet months. Gayo Luwes District is a coconut region in the centre of the country. Not only were the results of matching for the coconut commodity in each SST obtained by using map-based planning geographic information systems, but it was also discovered that rainfall ranged from 3100 mm/year, temperatures went from 23oC to 24oC, base saturation was in the very low to low category (3.91% -35.16%), pH H2O is classified as acidic (4.6-4.9), drainage is slightly obstructed, relatively fast and good, slopes are sloping to steep (12%-26 ) and textures with values little fine, smooth and rather rough are the limiting factors dominant. Other findings also suggest that applying organic material in garbage and compost to Red Yellow Podzolic soil in Batanghari, Jambi, increases Ca-dd and base saturation, and liming is done to raise the pH of H2O in soil units. Moderate to high levels of management can improve the slope limiting factor, such as delaying erosion, establishing a terrace, planting according to the contour, and growing covering plants. Irrigation and irrigation systems can assist in increasing the factors that limit rainfall. Keywords: Development, Coconut, Land Suitability, Gayo Lues

Analysis of rainfall data to develop the classification criteria for identifying agro-climate resources on the field

The issue of climate change demands an update on the existing agro-climate map of Indonesia. For this purpose, in 2019 the Indonesian Agro-climate Resource Map was prepared. One of the stages of mapping is rainfall classification. This paper describes the analysis of rainfall to produce the classification used in the Indonesian Agro-climate Resource Map. The analysis used the monthly and annual rainfall data from 4087 stations with various observation lengths period between 1980-2010. The results of the analysis show that there is a proportional relationship between annual rainfall and the number of consecutive wet months (R2 = 0.776), as well as an inversely proportional relationship between annual rainfall and the number of consecutive dry months (R2 = 0.64), and between the number of consecutive dry months with the consecutive wet months (R2 = 0.72). The results of the rainfall analysis divided the criteria for annual rainfall into 3 categories, namely wet (>2500 mm/year), moderate (1500-2500 mm/year) and dry, (<1500 mm/year); dividing the criteria for dry months into 3 categories, namely <3, 3-7, and >7 months; and dividing the criteria for the number of wet months into 4 categories, namely <3, 3-4, 5-9, >9 months. To improve the adaptation capacity of users and to assist quickly identification in the field, a Triangle Diagram is designed which can be used to identify the value of annual rainfall, the number of consecutive wet months, the number of consecutive dry months and the crop planting patterns.

Mapping Climate Classification of Oldeman in Agricultural Resources Management in South Tapanuli District

The Oldeman classification system is very useful in the classification of agricultural land for food crops in Indonesia using the element of rainfall. The criteria are based on the calculation of wet months (BB) and dry months (BK), respectively, with the limits taking into account the chance of rain, effective rain and water requirements for plants. With the Oldeman climate classification, a cropping pattern system can be determined in an area. Based on the research results obtained 4 types of climate in the South Tapanuli region, namely: D1, D2, E1, and E2. The wettest climate type in the Sipirok region is climate type D1 with 4-5 wet months and ,2 dry months. And those that are suitable for planting short-lived rice are 3 (three) harvests or short-lived rice is 2 (two) harvests and secondary crops 1 (sastu) harvests. The driest climate types in the East Angkola region are climate types E1 and E2 with the number of wet months ,3 and the number of dry months 6-7. What is suitable for planting short-lived lowland rice is 1 (one) harvest and secondary crops 2 (two) times, the second special harvest falls in the dry season. The topographical condition of an area greatly influences the climatic conditions of the area. With a good climate classification and suitable for rice plants without irrigation assistance, the climate types are D1 and D2, namely in Sipirok District, West Angkola District and a Small Part of Saipar Dolok Hole and Batang Angkola Districts. Meanwhile, the East Angkola sub-district can be planted with rice with the help of irrigation, especially in the dry season.

IKLIM DAN POTENSI TEGAKAN SENGON (Falcataria moluccana) DI HUTAN RAKYAT DESA JATI BALI KABUPATEN KONAWE SELATAN

This study aims to determine the climatic conditions that occur at Sengon cultivation sites and determine the standing potential number of trees, base area, and volume of sengon stands in community plantation forests that follow the people's seed garden program. Data collection is carried out in August to November 2018. The location of this village is at the coordinates of 04° 5'12 '' - 04°3'15'' LS and 122° 24'00'' - 122° 23'00'' BT and at altitude of 108 m above sea level. The population in this study is the sengon stand with an area of 5.8 ha. The sample area is determined with an intensity of 6.2% and the area of 1 plot is 0.04 ha, so the number of plots is 9 units. The results showed that 1) climatic conditions in the study location are classified as type B climate or wet (Schmidth-Ferguson method) including the category of tropical rain forests with an average number of wet months (BB) 9.2 and dry months (BK) 1.5 with a Q value of 0.16. Average annual rainfall is 2 662.6 mm, the monthly average rainfall of the highest in May was 347.4 mm with an average number of rainy days by 22.5 days and the lowest in September was 83.0 mm with an average rainy day of 11 days, while the longest rainy day occurred in April during 22.6 days with rainfall reaching 262.1 mm and the fastest occurred in October for 10.3 days with rainfall reaching 101.7 mm. The average annual temperature is around 230C with an 320C, with the lowest monthly average of 25.3oC (August) - 28.1oC (December). This fact indicates that the climatic conditions in Jati Bali Village South Konawe District are suitable for the development of sengon plants. 2) the potential of sengon stands in the village of Jati Bali South Konawe Regency, namely the number of trees 866 btgha-1, base area of 9.76 m2ha-1, volume of stands of 94.15 m3ha-1.

Application of Structural Equation Modeling to Control Anthracnose Disease Attacking Red Chili in Several the East Java Production Center

This research aims to apply structural equation modeling to design some anthracnose control alternatives that attack red chili plants in several production centers in East Java, Indonesia. The research method was conducted by surveying in five centers of red chili production including Malang Wajak, Malang Pujon, Kediri, Madiun, and Tuban. In each research location, 20 farmers and respondent farmers were observed by purposive sampling. Latent variables observed were the yield, disease percentage, climate, soil, geography, and cultivation techniques. Data were analyzed using structural equation modeling with Smart PLS 3.14 for students. Latent variables that have the effect of suppressing the development of anthracnose disease are selected and tested through factorial randomized block design experiment. The results showed that the intensity of anthracnose disease in red chili plants was directly influenced by climate (number of wet months and annual rainfall) and soil conditions (soil organic matter). Whereas cultivation techniques have an indirect effect through soil latent variables. Latent variables that directly affect the production of red chili are geography (height), soil (soil organic matter), and anthracnose disease variables. Thus, to control anthracnose disease, it is best to plant red chili in the dry season and in fields that have high organic matter content.

Sistema de información agroclimático para México- Centroamérica (SIAMEXCA)

Se obtuvo un sistema de información conformado por imágenes raster mensuales, estacionales y anuales, correspondientes a parámetros climáticos y agroclimáticos para la región México-Centroamérica. Este logro involucró procesos de conformación de bases de datos climáticos diarios y mensuales para el período 1961-2010, revisión de información para eliminar datos aberrantes y estimar datos perdidos; interpolación geográfica mediante el método Anusplin para generar imágenes raster mensuales de variables climáticas básicas (temperatura máxima, temperatura mínima, precipitación), álgebra de mapas y análisis espacial para generar parámetros agroclimáticos derivados de las variables climáticas básicas; utilización de información climática de una red de estaciones agrometeorológicas automatizadas para estimar parámetros ajustados al método de referencia; estimación de parámetros agroclimáticos mediante métodos indirectos y utilización de información derivada de modelos de asimilación de datos para la generación de parámetros agroclimáticos complementarios. Los resultados mostraron la obtención de un sistema de información compuesto de imágenes raster que representan el valor promedio para el período 1961-2010 de 144 variables mensuales (temperatura máxima Tx, temperatura mínima Ti, temperatura media Tm, rango térmico RT, suma térmica ST, grados-día desarrollo acumulados GDD, fotoperíodo F, precipitación P, evapotranspiración potencial ETP, índice de humedad IH, radiación solar Rs y humedad relativa HR); 41 variables estacionales correspondientes a la estación de crecimiento (las variables anteriores más duración de la estación de crecimiento DEC, y número de mese húmedos MH= P≥ETP); 13 variables anuales (mismas variables mensuales más número de meses húmedos) y la variable altitud. Las imágenes raster están referidas en el sistema WGS, pueden ser utilizadas en cualquier sistema de información geográfica (SIG) y cuentan con una resolución de 30” arco. El sistema es potencialmente útil para caracterizar la variación de las condiciones agroclimáticas de México y Centroamérica.&#x0D; &#x0D;

Intensity of vascular streak dieback in different cocoa clones and various agro-climatic conditions

Vascular streak dieback (VSD) is one of the main diseases on cocoa. This disease can produce a heavy damage in susceptible plants. Agro-climatic condition influences the VSD disease severity level. A study on the relationship between agro-climatic condition and VSD disease severity was conducted in eight locations which were selected based on difference in agro-climatic conditions including altitude, rainfall, number of wet, and dry months. Randomized complete block design was used consisting of eight agro-climatic conditions as treatments which consisted of 200 trees samples, and scored for VSD intensity. A study was also conducted on the response of cocoa clones with different level of resistance at different altitude at Kendeng Lembu, Jatirono, Sungai Lembu, Banjarsari, and Sumber Asin Plantations. A split plot design was applied consisting of two factors. The first factor was location including Pager Gunung (highland) and Besaran (lowland). The second factor was clone resistance with two levels: PA 191 (resistant) and BL 703 (susceptible). VSD scores and stomatal characteristics (stomata number, stomata diameter, and stomata aperture) were determined. The results of experiment showed that VSD scoring differed significantly between the eight agro-climatic conditions. The highest VSD score occurred in the lowland (Gereng Rejo, Banjarsari Plantation, 38 m asl.), where the average annual rainfall was 2161 mm, with five dry months. Cocoa trees in Sumber Asin (580 m asl.), with the average annual rainfall of 2302 mm and 8.5 wet months/3.5 dry months were mostly free of VSD disease. Altitude was positively correlated with rainfall, and negatively correlated with VSD severity. Number of wet months was negatively correlated with VSD severity. Conversely, number of dry months was positively correlated with VSD. The result indicated that genotype, environment, or their interaction did not significantly affect number and aperture of stomata. Although stomatal diameter was significantly affected by environment, genotypes or their interaction with environment did not influence this character.

Paleoclimatic records of Late Triassic paleosols from Central Ethiopia

The present study documents the major paleosols types within the Lower Adigrat Sandstone in the Blue Nile Basin of central Ethiopia, with the aim of unraveling the paleoclimatic signatures embedded in them. The paleosols developed within an 80-m-thick siliciclastic succession deposited in a mixed tide- and wave-dominated incised valley estuary during the Late Triassic.Based on down-profile variations in pedogenic features, three major paleosol types (i.e., types I, II and III) were identified. Type I paleosols dominate the lower part of the section and are interpreted as moderately well-drained argillic Vertisols. The dominant pedogenic process was shrinking and swelling of expandable clays (i.e., smectite) through repeated wetting and drying cycles. The morphologies and the mineralogy of the paleosols provide persuasive evidence for pedogenesis under semi-arid subtropical climatic conditions with pronounced wet-dry seasonality, highly fluctuating soil moisture regime, and deep groundwater table. The presence of a calcic Bk horizon deep in the profiles is consistent with elevated soil moisture deficits and low to moderate mean annual precipitation (MAP). Type II paleosols, interpreted to represent vertic Gleysols, are more common in the middle part of the section. The pervasive gleying reflects poor soil drainage and a shallow groundwater table where the soil is waterlogged most of the year. These paleosols suggest a humid tropical climate characterized by alternating wet-dry seasonality but with more wet months per year. The top of the unit is dominated by type III paleosols that represent gleyed Oxisols, reflecting a more humid equatorial climate marked by wet seasons, elevated annual soil moisture content, and a high water table. The presence of plinthite/laterite is in agreement with a wet equatorial climate characterized by extensive chemical weathering and long periods of landscape stability.The observed vertical progression in the major paleosol types from Vertsols to Gleysols and Oxisols implies a systematic change in the number of wet months, most probably in response to regional tectonics and long-term climate change. Because the number of wet months is, in part, related to latitude and monsoonal climates, the upward stratigraphic trend in paleosol orders is interpreted to signal the northward or equatorward migration of the Blue Nile Basin and central Ethiopia within Pangea from dry subtropical low-latitudes in the early Late Triassic (Carnian‐Norian) toward the humid, wet equatorial, possibly monsoonal, paleoclimatic zone in the Late Triassic (Norian‐Rhaetian).

Analysis of rainfall seasonality from observations and climate models

Two new indicators of rainfall seasonality based on information entropy, the relative entropy (RE) and the dimensionless seasonality index (DSI), together with the mean annual rainfall, are evaluated on a global scale for recently updated precipitation gridded datasets and for historical simulations from coupled atmosphere-ocean general circulation models. The RE provides a measure of the number of wet months and, for precipitation regimes featuring one maximum in the monthly rain distribution, it is related to the duration of the wet season. The DSI combines the rainfall intensity with its degree of seasonality and it is an indicator of the extent of the global monsoon region. We show that the RE and the DSI are fairly independent of the time resolution of the precipitation data, thereby allowing objective metrics for model intercomparison and ranking. Regions with different precipitation regimes are classified and characterized in terms of RE and DSI. Comparison of different land observational datasets reveals substantial difference in their local representation of seasonality. It is shown that two-dimensional maps of RE provide an easy way to compare rainfall seasonality from various datasets and to determine areas of interest. CMIP5 models consistently overestimate the RE over tropical Latin America and underestimate it in Western Africa and East Asia. It is demonstrated that positive RE biases in a GCM are associated with simulated monthly precipitation fractions which are too large during the wet months and too small in the months preceding the wet season; negative biases are instead due to an excess of rainfall during the dry months.

Rainfall variability and the trends of wet and dry periods in Bangladesh

AbstractSpatial patterns of annual and seasonal rainfall trends of Bangladesh over the time period 1958–2007 has been assessed using rainfall data recorded at 17 stations distributed over the country. Mann–Kendall trend test and the Sen's slope method are used to detect the significance and the magnitude of rainfall change, respectively. Historical dry and wet months are identified by using standardised precipitation index method and their trends are analysed to assess the possible change in wet and dry events in Bangladesh. The result shows a significant increase in the average annual and pre‐monsoon rainfall of Bangladesh. The number of wet months is found to increase and the dry months to decrease in most parts of the country. Seasonal analysis of wet and dry months shows a significant decrease of dry months in monsoon and pre‐monsoon. Copyright © 2009 Royal Meteorological Society

Observed changes of drought/wetness episodes in the Pearl River basin, China, using the standardized precipitation index and aridity index

Monthly precipitation data of 42 rain stations over the Pearl River basin for 1960–2005 were analyzed to classify anomalously wet and dry conditions by using the standardized precipitation index (SPI) and aridity index (I) for the rainy season (April–September) and winter (December–February). Trends of the number of wet and dry months decided by SPI were detected with Mann-Kendall technique. Furthermore, we also investigated possible causes behind wet and dry variations by analyzing NCAR/NCEP reanalysis dataset. The results indicate that: (1) the Pearl River basin tends to be dryer in the rainy season and comes to be wetter in winter. However, different wetting and drying properties can be identified across the basin: west parts of the basin tend to be dryer; and southeast parts tend to be wetter; (2) the Pearl River basin is dominated by dry tendency in the rainy season and is further substantiated by aridity index (I) variations; and (3) water vapor flux, moisture content changes in the rainy season and winter indicate different influences of moisture changes on wet and dry conditions across the Pearl River basin. Increasing moisture content gives rise to an increasing number of wet months in winter. However, no fixed relationships can be observed between moisture content changes and number of wet months in the rainy season, indicating that more than one factor can influence the dry or wet conditions of the study region. The results of this paper will be helpful for basin-scale water resource management under the changing climate.

Desiccation and thermal tolerance of eggs and the coexistence of competing mosquitoes

We tested the hypothesis that differences in temperature and desiccation tolerances of eggs of the container-dwelling mosquitoes Aedes albopictus and Aedes aegypti influence whether invading A. albopictus coexist with or exclude A. aegypti in Florida. In the laboratory, egg mortality through 30 days for A. albopictus was strongly temperature and humidity dependent, with low humidity and high temperature producing greatest mortality. In contrast, mortality through 30 days and through 60 days for A. aegypti was very low and independent of temperature and humidity. Mortality through 90 days for A. aegypti showed significant effects of both temperature and humidity. In the field, the proportion of vases occupied by A. albopictus was significantly lower at four of six sites at the start of the wet season (after a dry period) versus well into the wet season (after containers had held water for weeks). The proportion of vases occupied by A. aegypti was independent of when during the wet season vases were sampled. These results imply that dry periods cause disproportionately greater mortality of A. albopictus eggs compared to A. aegypti eggs. Container occupancy at tire and cemetery sites was significantly related to two principal components derived from longterm average climate data. Occupancy of containers by A. albopictus was greatest at cool sites with little or no dry season, and decreased significantly with increasing mean temperature and increasing number of dry months. In contrast, occupancy of containers by A. aegypti was lowest at cool sites with little or no dry season, and increased significantly with increasing mean temperature and increasing dry season length, and decreased significantly with total precipitation and number of wet months. We suggest that local coexistence of these species is possible because warm, dry climates favor A. aegypti and alleviate effects of competition from A. albopictus via differential mortality of A. albopictus eggs.

A preliminary study of changes in forest stratification along environmental gradients in Southeast Asia

AbstractChanges in forest stratification along environmental gradients in Southeast Asian forests were studied, by applying Quantification Method I to the records of tree height inventories and environmental conditions in 29 study forest stands. To stratify individual trees into subpopulations in a stand, an empirical and graphical method was used. After stratifying all the component individuals of the stand into subpopulations, the number of subpopulations per stand and mean tree height per subpopulation were calculated and adopted as indices of forest stratification. Of the two indices, the latter index changed linearly with respect to the maximum tree height in the stand. Hence, the number of subpopulations and the maximum tree height as a substitute for mean tree height per subpopulation were biotic dependent variables in the application of Quantification Method I, while abiotic independent variables were the following six categorized environmental factors: the number of wet months with over 100 mm month−1 rainfall in a year, occurrence of fog, mean annual temperature, magnesium accumulation in mineral soil, soil water drainage, and forest fire. It was concluded that these biotic and abiotic variables were the components of multivariate regression models, which successfully explained the development of forest stratification in terms of habitat conditions.

Sunspots and Weather

I HAVE thought the following may be worth attention. Count the number of warm months, and the number of wet months, at Greenwich, in each year, since 1841 (i.e. months above average in either case). Select the values in each of the five-year groups having a sunspot maximum year central; and the same with minimum.