Salinity-affected threshold yield loss: A signal of adaptation tipping points for salinity management of dry season rice cultivation in the coastal areas of Bangladesh

Studies on percent cover and biomass of seagrasses from Shwe Thaung Yan coastal areas (Inn Din Gyi, Kyauk Nagar and Phoe Htaung Gyaing), the Southern parts of Rakhine Coastal Region, were carried out between March and August, 2018. A total of 8 species of seagrasses, namely Syringodiumisoetifolium (Ascherson) Danty, Halodulepinifolia (Miki) den Hartog, Haloduleuninervis (Forsskal) Ascherson, Cymodocearotundata Ehrenberg et Hemprich ex Ascherson, C. serrulata (R. Brown) Ascherson et Magnus, Thalassiahemprichii(Ehrenberg) Ascherson, Halophila major (Zoll.) Miquel and Enhalusacoroides (Linnaeus f.) Royle, were recorded in three study sites. Seagrass meadow in this study showed seasonal variations in both percent cover and biomass. Total seagrass coverage and biomass were higher in the dry season than in the monsoon season. Total seagrass coverage ranged between 8% and 75% in Phoe Htaung Gyaing, between 10% and 42% in Kyauk Nagar, and between 15% and 43% in Inn Din Gyi. Total seagrass mean biomass was 50.2413-259.846gdry.wtm-2 in Phoe Htaung Gyaing, 63.0194 -321.535gdry.wtm-2 in Kyauk Nagar, and 98.6819-416.237gdry.wtm-2 in Inn Din Gyi.

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Exploring the Major Climate-smart Agricultural Practices for Dry Season Crop Production in Salinity Affected Fallow Land in the Coastal Areas of Bangladesh

International Journal of Environment and Climate Change ◽

10.9734/ijecc/2021/v11i1030506 ◽

2021 ◽

pp. 185-192

Author(s):

Md. Abdul Awal

Keyword(s):

Crop Production ◽

Agricultural Practices ◽

Conservation Agriculture ◽

Safety Net ◽

Coastal Areas ◽

Dry Season ◽

Fallow Land ◽

Short Life Span ◽

Crop Varieties ◽

Study Results

The landmasses of the coastal areas of Bangladesh still remains under-utilized, thus cropping intensity is much less than the national average. Most areas remain fallow during dry (rabi) season from December to May due to presence of higher concentration of salts in soil and water, and scarcity of suitable irrigation water. Available adaptation options or technologies are not capable to solve these problems at all. Nevertheless, the areas receive a lot of water from monsoon rain, most of that rainwater is drain-out as surface runoff. The present study results suggest that the use of harvested rainwater and conservation agriculture either in combination or alone could mitigate the problem for bringing huge areas under crop cultivation. The public social safety net programmes such as cash-for-work, food-for-work etc. can be deployed for excavating or re-excavating the abandoned coastal ponds, ditches or canals for storing rainwater. Salt-, drought- and/or heat-tolerant crop varieties with short life span can also be cultivated to get the better results. Early plantation or growing crops with early-maturing varieties can ensure safer harvest in ahead of stress arrives. The avenues have immense potential as climate-smart practices for growing crops preferably non-rice crops during dry season in vast fallow land that will not only ensure food security for coastal people but could turn the entire southern Bangladesh as a food surplus zone. The findings refer the broad recommendation, therefore, specific research works based on the locations and resources available are necessary.

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A Water Stress Index for Tea (Camellia sinensis)

Experimental Agriculture ◽

10.1017/s0014479700015179 ◽

1989 ◽

Vol 25 (4) ◽

pp. 545-558 ◽

Cited By ~ 17

Author(s):

William Stephens ◽

M. K. V. Carr

Keyword(s):

Shoot Growth ◽

Yield Loss ◽

Relative Yield ◽

Dry Season ◽

Stress Index ◽

Water Stress Index ◽

Single Clone ◽

The Difference ◽

Limiting Value ◽

Simple Stress

SUMMARYA simple Stress Time Index (STI) for predicting yield loss in the tea crop due to drought is proposed, based on the daily summation of the difference between the potential soil water deficit and a specified limiting value. Validation of the technique with results from a line-source irrigation experiment with a single clone in the Southern Highlands of Tanzania suggests that there is a linear relationship between STI and relative yield loss during the warm dry season. As a result of changes in the composition of the shoot population at each harvest the apparent critical deficit at which shoot growth is restricted increases from below 20 to 300 mm as the dry season progresses. The rate of yield loss with increasing STI also varies through the dry season for the same reason.

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A Subregional Model of System Dynamics Research on Surface Water Resource Assessment for Paddy Rice Production under Climate Change in the Vietnamese Mekong Delta

Climate ◽

10.3390/cli8030041 ◽

2020 ◽

Vol 8 (3) ◽

pp. 41

Author(s):

Tuu Nguyen Thanh ◽

Van Pham Dang Tri ◽

Seungdo Kim ◽

Thuy Nguyen Phuong ◽

Thuy Lam Mong ◽

...

Keyword(s):

Climate Change ◽

Water Resources ◽

System Dynamics ◽

Sea Level ◽

Water Consumption ◽

Human Activities ◽

Environmental Changes ◽

Mekong Delta ◽

Coastal Areas ◽

Dry Season

Effective water management plays an important role in socioeconomic development in the Vietnamese Mekong Delta (VMD). The impacts of climate change and human activities (that is, domestic consumption and industrial and agricultural activities) vary in different subregions of the delta. In order to provide intersectoral data for determining the significantly impacted subregions of the VMD, the present study simulated interactions between local climatic patterns, human activities, and water resources using a system dynamics modeling (SDM) approach with each subregion as an agent of the developed model. The average rainfall and temperature of 121 subregions in the VMD were collected during 1982–2012, and the future changes of climate by provinces were based on the Representative Concentration Pathways (RCP) scenarios (RCP4.5 and RCP8.5) by the end of 21st century. The assessment was based on the levels of impact of various factors, including (1) water consumption, (2) differences between evapotranspiration and rainfall, and (3) spatial distribution of salinity intrusion over the delta scale. In the coastal areas, as well as the central and upstream areas, water resources were projected to be affected by environmental changes, whereas the former, characterized by the lack of surface freshwater, would be affected at a greater scale during the dry season. Besides, the sea level rise would lead to an increase in negative impacts in the eastern coastal areas, suggesting that water-saving techniques should be applied not only for agriculture, but also for industry and domestic water consumption during the dry season. In addition, the south subregions (that is, the western subregions of the Hau River except for An Giang) were likely to be flooded due to the simulated high rainfall and seasonal rises of sea level during the wet season. Therefore, the alternative forms of settlement and livelihood should be considered toward balance management with changing delta dynamics.

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Improving irrigation management in dry season rice cultivation for optimum crop and water productivity in non-traditional rice ecologies

Irrigation and Drainage ◽

10.1002/ird.572 ◽

2011 ◽

Vol 60 (2) ◽

pp. 174-178 ◽

Cited By ~ 3

Author(s):

A. Ghosh ◽

O. N. Singh ◽

K. S. Rao

Keyword(s):

Water Productivity ◽

Irrigation Management ◽

Dry Season ◽

Rice Cultivation ◽

Rice Ecologies ◽

Traditional Rice

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Temporal Analysis for Multi-hazard Risk Assessment of Rice Cultivation in Coastal Areas: A Case Study of Soc Trang, Vietnam

10.21203/rs.3.rs-137318/v1 ◽

2021 ◽

Author(s):

Thanh Quoc Vo ◽

Trung Hieu Nguyen ◽

Vo Thi Phuong Linh

Keyword(s):

Risk Assessment ◽

Natural Disasters ◽

Tropical Cyclones ◽

Rice Yield ◽

Hazard Index ◽

Coastal Areas ◽

Rice Cultivation ◽

Rice Crop ◽

Saline Intrusion ◽

Very High

Abstract Rice is an important human crop and rice cultivation is threatened due to natural disasters, leading to negative effects on national and global food security. The natural disasters, such as tropical cyclones and saline intrusion, have dramatic influences in coastal regions. To investigate possible impacts of these disasters on rice cultivation, it needs an efficient tool to assess potential disasters impacts and a risk index is highly applicable. Therefore, this study aims at establishing a risk assessment of rice production in coastal areas under effects of tropical cyclones and saline intrusion. We adopted risk definition introduced by IPCC (2014) in which risk is a function of hazard, exposure and vulnerability. Multiple hazards of tropical cyclones and saline intrusion were indicated by their frequency and severity at some critical levels of 25%, 50% and >50% rice yield reduction. Each hazard was weighted by its damage on rice yield. Exposure and vulnerability of rice crops are evaluated at different growing phases. Tropical cyclone hazard index was ranked high and very high in the wet season while salinity hazard index was ranked very high in the dry season. Due to the combined effects of tropical cyclones and salinity, rice crop is highly susceptible during the reproduction phase and at the panicle initiation stage particularly. Based on the cropping calendar of My Xuyen, the period of October-November was the very high vulnerability period since it had the largest rice cultivable area and rice crops were at the reproduction phase. This result shows that rice crops are at high risk in October and November. Noticeably, saline intrusion reaches the highest level in April and May, but no risk is at this period because of no rice crop cultivated. This can reflect a measure to reduce risk by adjusting the cropping calendar.

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AGRO-ECOLOGICAL AND SOCIO-ECONOMIC ASPECTS OF CROP PROTECTION IN CHILI-BASED AGRIBUSINESS IN CENTRAL JAVA

Agriekonomika ◽

10.21107/agriekonomika.v6i2.2294 ◽

2017 ◽

Vol 6 (2) ◽

pp. 120

Author(s):

Joko Mariyono

Keyword(s):

Yield Loss ◽

Insect Pests ◽

Control Measure ◽

Crop Protection ◽

Dry Season ◽

Economic Losses ◽

Wet Season ◽

Potential Yield ◽

Pests And Diseases ◽

Central Java

<p><em>Chili is an important cash crop in Indonesia. This study is to analyze socio-economic aspect of chili production in three selected communities of three districts —Magelang, Brebes, and Rembang— that represent distinct agroecosystems of chili cultivation within Central Java province. This study uses quantitative descriptive methods. Data were compiled from a series of surveys in 2010-2011. The results of analyses were presented in table and graphical forms to compare and contrast selected relevant variables associated with crop protection. The results show that yield loss due to pests and diseases was considerable, and some of these problems were becoming difficult to control. The economic losses varied, which depended on many factors. The potential yield loss could reach 100 percent. Among the eight major insect pests reported by farmers during the dry season, thrips, mites, and whitefly infestations were most severe. Likewise, among five diseases noted by farmers, the three most important—anthracnose (Colletotrichum capsici), gemini-viruses, and Phytophthora—were more serious than the others. During the wet season, risk of anthracnose was very high; in the dry season, risk of yield lost to gemini-viruses and Phytophthora was high. Within a province, the severe outbreaks of insect pests and diseases varied across locations and seasons. Farmers applied control measure using pesticides and other alternative controls. However, the problem still persisted. There is a crucial need to solve the problems by enhancing farmers’ knowledge and involving research institutions focusing on crop protection strategy.</em></p>

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Water requirements of tobacco grown under irrigation at Clare, North Queensland.

Australian Journal of Agricultural Research ◽

10.1071/ar9530168 ◽

1953 ◽

Vol 4 (2) ◽

pp. 168

Author(s):

WJ Lovett

Keyword(s):

Early Growth ◽

Coastal Areas ◽

Dry Season ◽

Plant Establishment ◽

Water Requirements ◽

Yield And Quality

An investigation of the water requirements of tobacco grown during the dry season (July–December) in the coastal areas of north Queensland was undertaken at Clare during the years 1948 and 1949. There were eight spray treatments in 1948 and four in 1949. Total amount of water applied per acre varied from 8 to 27.5 in. The best results were obtained with 1.0–1.5 acre-in. of water for plant establishment in the field, followed by a total of approximately 20 acre-in. during growth. Heavy applications retarded early growth and tended to affect yield, but not quality, adversely. With low watering, plants were stunted and failed to ripen satisfactorily, whereas highest rates were above the optimum for yield and quality.

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