Amplified warming induced by large-scale application of water-saving techniques

Large-scale agricultural activities can exacerbate global climate change. In the past three decades, over 5 Mha of cultivated land have been equipped with Water-Saving Techniques (WST) in Northwest China to cope with water scarcity. However, the effect of WST on local climate and its mechanisms are not yet understood. Here we quantified the local climatic effect by comparing temperature and humidity at controlled and irrigated sites before and after the large-scale implementation of WST. Results show that the substantial reduction in irrigation water use has led to an average increase of 0.3°C in growing-season temperature and reduced relative humidity by 2%. Near-surface air temperature responds nonlinearly to percentage area of WST and a threshold value of 40% is found before any noticeable warming effect over the study area. Moreover, it is found that regions with relatively humid climates respond more significantly to WST. This study reveals the mechanism of WST on near-surface climate and highlights the importance of incorporating this feedback into sustainable water management and land-surface models for assessing the impact of irrigated agriculture on regional climate change.

Socioeconomic impact of small-scale irrigation on household’s livelihood improvement in Bena-Tsemay district of South Omo zone, Southern Ethiopia

The study investigated the socioeconomic impacts of irrigated agriculture and factors affecting the decision of agro-pastoralists to participate in irrigation during 2017-2018. The result depends on cross-sectional data collected from a sample of 120 households of which 90 irrigation users and 30 non-users using a combination of purposive and random sampling. The data were analyzed using descriptive statistics and logistic regression to assess factors that affect participation in irrigation. The logistic regression model revealed that age, credit access, extension contact, distance to water, and labor force significantly affected the decision of given agro-pastoralists to participate in irrigation practices at less than 5% probability levels. This indicates that the explanatory variables included in the model influence the decision of agro-pastoralists to participate in irrigation practices. Therefore, the provision of credit service to allow rapid progress in introducing technologies like tractors for farming practices and frequent extension contact with irrigation users could enhance the productivity in the area. Int. J. Agril. Res. Innov. Tech. 11(2): 139-146, Dec 2021

An effective evapotranspiration estimation scheme based on statistical indicators for sustainable environments in humid and semi-arid area of Khyber Pakhtunkhwa, Pakistan

Reference evapotranspiration (ETo) is critical for irrigation design and water management in rainfed and irrigated agriculture. The Penman-Monteith (FAO-56(PM)) equation was demonstrated to be the most reliable and adaptive to a wide range of humid to semi-arid climates. However, it requires several environmental parameters (e.g., wind speed, solar radiation), rarely available in developing countries. Therefore, numerous temperature-based formulas have been designed to address this issue for various environments. Their calibration and validation against the local climate frequently lead to increases in performance. We revised the Hargreaves exponent (EH) and substituted a value of (0.16) for the original value (0.5). The modified Hargreaves formula enhances the ETo predictions with a mean absolute error ranging from (0.791) mm per day for Balakot to (2.36) mm per day in Risalpur, averaging (3.797) mm per day, as compared to the Hargreaves-Samani (16.827) mm per day. In general, all the selected models showed high accuracy. However, the modified Hargreaves equation appeared to be the most promising results. It ranked first in (50%) of the whole area based on the standard error of estimate for estimating ETo in Khyber Pakhtunkhwa. Additional research must be conducted to determine the study's relevance to other regions.

Classification of determinant factors of irrigated vegetable problems using exploratory factor analysis in Swaida governorate, Syria

<p class="042abstractstekst">The objective of this research was to classify the determinant factors of irrigated vegetable problems and the amount of variance that is explained by each factor in Swaida Governorate/ Syria by using the Exploratory Factor Analysis. The research is based on the data which were collected through questionnaires that were obtained according to the opinions of farmers. It included questions about some of the social and economic characteristics of farmers, and the concerning problems related to irrigated agriculture by using multiple-choice questions (on a 3-point scale) during the 2019-2020 Based on a sample size of 92 farmers, representing 54.9 % of the studied statistical community, and distributed randomly within the areas of spread of irrigated vegetable cultivation.. The results showed the success of using the exploratory factor analysis technique, using the Principal components methodology and Varimax in classifying six factors with an initial eigenvalues greater than one for each, and these factors are: agricultural technological progress, agricultural employment, sale outlets, natural conditions, prices, production requirements. These factors explained (13.21 %, 12.65 %, 12.55 %, 11.12 %, 10.94 %, and 9.85 %) of the total variance respectively, and together explained 70.33 %.</p>

PANORAMA DA EVOLUÇÃO DA AGRICULTURA IRRIGADA NO SUDESTE DO BRASIL ENTRE 2006 E 2017

PANORAMA DA EVOLUÇÃO DA AGRICULTURA IRRIGADA NO SUDESTE DO BRASIL ENTRE 2006 E 2017 CÉSAR DE OLIVEIRA FERREIRA SILVA1; FERNANDO FERRARI PUTTI2 E RODRIGO LILLA MANZIONE3 1 Departamento de Engenharia Rural, Faculdade de Ciências Agronômicas, Universidade Estadual Paulista", Avenida Universitária, n° 3780, Altos do Paraíso, 18610-034, Botucatu, São Paulo, Brasil, [email protected]. 2 Departamento de Engenharia de Biossistemas, Faculdade de Ciências e Engenharia, Universidade Estadual Paulista, Rua. Domingos da Costa Lopes, nº 780, Jardim Itaipu, 17602-496, Tupã, São Paulo, Brasil, [email protected]. 3 Departamento de Engenharia de Biossistemas, Faculdade de Ciências e Engenharia, Universidade Estadual Paulista, Rua. Domingos da Costa Lopes, nº 780, Jardim Itaipu, 17602-496, Tupã, São Paulo, Brasil, [email protected]. 1 RESUMO O presente estudo buscou contribuir no debate sobre a situação da irrigação no Brasil, dando ênfase na região Sudeste. Buscou-se entender, a partir dos dados dos Censos Agropecuários do IBGE de 2006 e 2017, quais direções a agricultura irrigada tomou no Sudeste do Brasil durante esse período. Houve aumento na área irrigada no Brasil em todas as regiões geográficas, atingindo 6,9 milhões de hectares (Mha) em 2017. No período 2006-17 a expansão da área irrigada no estado de Minas Gerais foi de 616 mil hectares, em São Paulo foi de 321 mil hectares e de 155 mil hectares no Espírito Santo. Na região Sudeste a irrigação por gotejamento é majoritária em área, com 25% da área irrigada, seguida de forma acirrada pela irrigação por aspersão (24%) e por pivô central (23%). A área irrigada na região Sudeste, segundo o Censo 2017, é destinada majoritariamente para cultivo de lavouras temporárias (48%), lavouras permanentes (29%), horticultura e floricultura (14%) e pecuária (10%). Essas informações são importantes para o planejamento do crescimento sustentável da agricultura irrigada e o uso eficiente dos recursos hídricos. Palavras-chave: área irrigada, Censo Agropecuário; métodos de irrigação. SILVA, C. O. F.; PUTTI, F. F.; MANZIONE, R. L. OVERVIEW OF IRRIGATED AGRICULTURE EVOLUTION IN SOUTHEASTERN BRAZIL BETWEEN 2006 AND 2017 2 ABSTRACT This research aimed to contribute to the debate about the current situation of irrigation in Brazil, with emphasis on the Southeast region. Based on data from the IBGE Agricultural Censuses of 2006 and 2017, we aimed to understand which directions irrigated agriculture has taken in Southeastern Brazil during this period. There was an increase in the irrigated area in Brazil in all geographical regions, reaching 6.9 million hectares (Mha) in 2017. In the period 2006-17, the expansion of the irrigated area in the state of Minas Gerais was 616,000 hectares, in São Paulo it was 321,000 hectares and 155,000 hectares in Espírito Santo. In the Southeast region, drip irrigation is the majority in the area, with 25% of the area irrigated, followed by sprinkler irrigation (24%) and central pivot (23%). The irrigated area in the Southeast region, according to the 2017 Census, is mostly for temporary crops (48%), permanent crops (29%), horticulture and floriculture (14%), and livestock (10%). These information are important for planning the sustainable expansion of irrigated agriculture and efficient water use. Keywords: irrigated area, census of agriculture, irrigation methods.

BALANÇO HÍDRICO CLIMATOLÓGICO NORMAL E SEQUENCIAL DO MUNICÍPIO DE PEREIRA BARRETO - SP COMO AUXILIO PARA O PLANEJAMENTO DA AGRICULTURA IRRIGADA

BALANÇO HÍDRICO CLIMATOLÓGICO NORMAL E SEQUENCIAL DO MUNICÍPIO DE PEREIRA BARRETO - SP COMO AUXILIO PARA O PLANEJAMENTO DA AGRICULTURA IRRIGADA PEDRO ALCANTARA DA SILVA ABREU1 E FERNANDO BRAZ TANGERINO HERNANDEZ2 1 Doutorando em Agronomia: Irrigação e Drenagem, Departamento de Engenharia Rural, Universidade Estadual Paulista, Avenida Universitária, n° 3780, Altos do Paraíso, 18610-034, Botucatu, São Paulo, Brasil. E-mail; [email protected]. 2 Professor Titular, Departamento de Fitossanidade, Engenharia Rural e Solos - DEFERS, Universidade Estadual Paulista, Avenida Brasil Sul, n° 56, Centro, 15385-000, Ilha Solteira, São Paulo, Brasil. E-mail: [email protected] 1 RESUMO Este trabalho teve como objetivo gerar um balanço hídrico climatológico (BHC) normal e sequencial para o município de Pereira Barreto, SP para identificar os períodos do ano com excedente e déficit de água no solo. Foram realizados dois BHCs para o município, determinados a partir do método de Thorthwaite e Mather (1955), com base nos dados das estações agrometereologicas automáticas Bonança e Santa Adélia, pertencentes à Rede Agrometeorológica do Noroeste Paulista, operada pela Unesp de Ilha Solteira. A precipitação média anual é de 1.214 mm e a evapotranspiração de 1.340 mm para a Estação Bonança, enquanto para a Santa Adélia, a precipitação média anual é de 1.204 mm e evapotranspiração de 1.574 mm. Com a Capacidade de Água Disponível (CAD) de 40 mm, os BHCs constataram sete meses de déficit hídrico no solo, entre março e outubro na Estação Bonança, localizada às margens do rio Tietê e de abril a novembro na Estação Santa Adélia, localizada na porção noroeste do município. O excesso de água no solo na Estação Bonança aconteceu entre os meses de novembro e fevereiro e na Santa Adélia entre janeiro e março. O BHC mostrou ser grande o risco de frustação de safra com culturas anuais no município sem a utilização de irrigação. Palavras-chave: evapotranspiração, déficit hídrico, irrigação, agrometeorologia, Noroeste Paulista. ABREU, P. A. S.; HERNANDEZ, F. B. T. NORMAL AND SEQUENTIAL CLIMATOLOGICAL WATER BALANCE IN THE MUNICIPALITY OF PEREIRA BARRETO - SP AS AID FOR THE PLANNING OF IRRIGATED AGRICULTURE 2 ABSTRACT This work aimed to generate a normal and sequential climatological water balance (BHC) for the municipality of Pereira Barreto, SP to identify the periods of the year with surplus and deficit of water in the soil. Two BHCs were carried out for the municipality determined by the method of Thorthwaite and Mather (1955), based on data from the automatic agro-meteorological stations Bonança and Santa Adélia, belonging to the Northwest Agro-meteorological Network of the Northwest, operated by Unesp of Ilha Solteira. The average annual precipitation is 1214 mm and the evapotranspiration is 1340 mm for the Bonança Station, while for the Santa Adélia Station, the average annual precipitation is 1204 mm and evapotranspiration is 1574 mm. With the available Water Storage (CAD) of 40 mm, the BHCs found seven months of water deficit in the soil, between March and October in the Bonança Station, located on the banks of the Tietê River and from April to November in the Santa Adélia Station, located in the northwest portion of the municipality. Excess water in the soil in the Bonança Station occurred between the months of November and February and in the Santa Adélia Station, between January and March. BHC showed a high risk of crop failure with annual crops in the municipality without the use of irrigation. Keywords: evapotranspiration, water deficit, irrigation, agrometeorology, Northwest Paulista.