Soil vulnerability index to climatic variability in coffee regions of Colombia

Global climate change is one of the main factors threatening agriculture. In this context, variations in precipitation have the strongest effect on soil fertility, plant nutrient availability, and erosion. This research aimed to assess soil vulnerability to climate variability in the central coffee-growing region of Colombia. This study analyzed soil components involved in the sustainability of the coffee production system as affected by extreme high and low precipitation events. For evaluation, three sensitivity indices were constructed, with a weighted aggregation structure and with weight values defined from expert knowledge. The indices were estimated by randomly selecting 432 coffee farms in the municipalities of Balboa and Santuario in Risaralda department and Salamina in Caldas department. The soil nutrient availability and conservation vulnerability index was moderate in the three municipalities (Balboa=2.87 and coefficient of variation-CV 13%; Santuario=2.88 and CV 10%; Salamina=2.9 and CV 9%). The soil leaching vulnerability index was very low in Balboa (4.33 and CV 3%) and Salamina (4.74 and CV 7%) and low in Santuario (3.57 and CV 19%). The soil loss vulnerability index was low in Balboa (3.32 and CV 10.03%) and Salamina (3.49 and CV 11.43%) and moderate in Santuario (3.13 and CV 9.34%). Lastly, the vulnerability of coffee-growing soil to climate variability was low in Balboa (3.33) and Salamina (3.45) and moderate in Santuario (3.09). Based on these results, in the three municipalities, coffee growers must introduce farming practices towards improving soil resilience and decreasing soil vulnerability to high and low precipitation extremes by adequately managing the sources and doses of fertilizers, soil conditioners, and compost and by implementing integrated management of weeds and litterfall.

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Testing Farmers’ Perception of Climate Variability: A Case Study from Kirtipur of Kathmandu Valley

Hydro Nepal Journal of Water Energy and Environment ◽

10.3126/hn.v11i1.7200 ◽

2012 ◽

pp. 30-34

Author(s):

Jiban Mani Poudel

Keyword(s):

Climate Change ◽

Climate Variability ◽

Global Climate ◽

Climatic Variability ◽

Global Perspective ◽

Kathmandu Valley ◽

Climatic Fluctuations ◽

Climate Fluctuations ◽

Global And Local

In the 21st century, global climate change has become a public and political discourse. However, there is still a wide gap between global and local perspectives. The global perspective focuses on climate fluctuations that affect the larger region; and their analysis is based on long-term records over centuries and millennium. By comparison, local peoples’ perspectives vary locally, and local analyses are limited to a few days, years, decades and generations only. This paper examines how farmers in Kirtipur of Kathmandu Valley, Nepal, understand climate variability in their surroundings. The researcher has used a cognized model to understand farmers’ perception on weather fluctuations and climate change. The researcher has documented several eyewitness accounts of farmers about weather fluctuations which they have been observing in a lifetime. The researcher has also used rainfall data from 1970-2009 to test the accuracy of perceptions. Unlike meteorological analyses, farmers recall and their understanding of climatic variability by weather-crop interaction, and events associating with climatic fluctuations and perceptions are shaped by both physical visibility and cultural frame or belief system.DOI: http://dx.doi.org/10.3126/hn.v11i1.7200 Hydro Nepal Special Issue: Conference Proceedings 2012 pp.30-34

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Southern Hemisphere Westerly Winds and Holocene climate variability on sub-Antarctic South Georgia

10.5194/egusphere-egu21-14641 ◽

2021 ◽

Author(s):

Maaike Zwier ◽

Anne Bjune ◽

Willem van der Bilt

Keyword(s):

Climate Variability ◽

Southern Hemisphere ◽

Global Climate ◽

Climatic Variability ◽

Pollen Record ◽

Long Distance ◽

Climate Conditions ◽

South Georgia ◽

Westerly Winds ◽

Southern Hemisphere Westerly Winds

<p>The Southern Hemisphere Westerly Winds play a major role in the global climate system. By driving circulation in the Southern Ocean and its subsequent effect on the upwelling of carbon-rich deep water, the Westerlies affect the oceans ability to take up atmospheric CO<sub>2</sub>. Furthermore, by impacting temperature conditions and moisture availability, the Westerlies act as a first-order control on local environmental conditions. Uncovering long term natural climatic variability in the sub-Antarctic is therefore crucial to understand how the global system might react under future climate changes. Due to the lack of land mass on the Southern Hemisphere, sub-Antarctic islands are essential for studying climate variability in this region; terrestrial records provide valuable insights into both local and regional surface climate conditions. We use a pollen record from Lake Diamond to provide detailed reconstructions of vegetation and climate on sub-Antarctic South Georgia for the last ~9900 years. Westerly Wind strength and position is inferred from long-distance transport of pollen from South America, Africa, and New Zealand. Additionally, changes in relative pollen abundance of native taxa occupying either upland (cold) or lowland (warm) environments are used to infer local climatic variation, supported by additional sedimentological proxies. On South Georgia we find long-distance transported pollen from several South American taxa, mainly Nothofagus, Ephedra and Asteraceae. They show a general increase in abundance throughout the Holocene, with peak influx between 2800 and 1500 cal yr BP, most likely caused by changes in the strength of the Southern Hemisphere Westerly Winds. In both our record and others, this interval is seen as the end of the Neoglacial period.</p>

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One Year Residual Effect of Sewage Sludge Biochar as a Soil Amendment for Maize in a Brazilian Oxisol

Sustainability ◽

10.3390/su13042226 ◽

2021 ◽

Vol 13 (4) ◽

pp. 2226

Author(s):

Joisman Fachini ◽

Thais Rodrigues Coser ◽

Alyson Silva de Araujo ◽

Ailton Teixeira do Vale ◽

Keiji Jindo ◽

...

Keyword(s):

Sewage Sludge ◽

Grain Yield ◽

Nutrient Availability ◽

Pyrolysis Temperature ◽

Residual Effect ◽

Soil Nutrient ◽

Mineral Fertilizer ◽

Corn Yield ◽

Soil Nutrient Availability ◽

One Year

The thermochemical transformation of sewage sludge (SS) to biochar (SSB) allows exploring the advantages of SS and reduces possible environmental risks associated with its use. Recent studies have shown that SSB is nutrient-rich and may replace mineral fertilizers. However, there are still some questions to be answered about the residual effect of SSB on soil nutrient availability. In addition, most of the previous studies were conducted in pots or soil incubations. Therefore, the residual effect of SSB on soil properties in field conditions remains unclear. This study shows the results of nutrient availability and uptake as well as maize yield the third cropping of a three-year consecutive corn cropping system. The following treatments were compared: (1) control: without mineral fertilizer and biochar; (2) NPK: with mineral fertilizer; (3) SSB300: with biochar produced at 300 °C; (4) SSB300+NPK; (5) SSB500: with biochar produced at 500 °C; and (6) SSB500+NPK. The results show that SSB has one-year residual effects on soil nutrient availability and nutrient uptake by maize, especially phosphorus. Available soil P contents in plots that received SSB were around five times higher than the control and the NPK treatments. Pyrolysis temperature influenced the SSB residual effect on corn yield. One year after suspending the SSB application, SSB300 increased corn yield at the same level as the application of NPK. SSB300 stood out and promoted higher grain yield in the residual period (8524 kg ha−1) than SSB500 (6886 kg ha−1). Regardless of pyrolysis temperature, biochar boosted the mineral fertilizer effect resulting in higher grain yield than the exclusive application of NPK. Additional long-term studies should be focused on SSB as a slow-release phosphate fertilizer.

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Nutrient use strategy and not competition determines native and invasive species response to changes in soil nutrient availability

Restoration Ecology ◽

10.1111/rec.13374 ◽

2021 ◽

Author(s):

Amanda E. Knauf ◽

Creighton M. Litton ◽

Rebecca J. Cole ◽

Jed P. Sparks ◽

Christian P. Giardina ◽

...

Keyword(s):

Invasive Species ◽

Nutrient Availability ◽

Soil Nutrient ◽

Soil Nutrient Availability ◽

Species Response ◽

Nutrient Use

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Assessing Impact of Climate Variability in Southwest Coastal Bangladesh Using Livelihood Vulnerability Index

Climate ◽

10.3390/cli9070107 ◽

2021 ◽

Vol 9 (7) ◽

pp. 107

Author(s):

Sabrina Mehzabin ◽

M. Shahjahan Mondal

Keyword(s):

Climate Variability ◽

Linear Regression Analysis ◽

Kendall Test ◽

Vulnerability Index ◽

Precipitation Anomaly ◽

Primary Data ◽

Precipitation Concentration Index ◽

Coastal Bangladesh ◽

Present Decade ◽

The Impact

This study analyzed the variability of rainfall and temperature in southwest coastal Bangladesh and assessed the impact of such variability on local livelihood in the last two decades. The variability analysis involved the use of coefficient of variation (CV), standardized precipitation anomaly (Z), and precipitation concentration index (PCI). Linear regression analysis was conducted to assess the trends, and a Mann–Kendall test was performed to detect the significance of the trends. The impact of climate variability was assessed by using a livelihood vulnerability index (LVI), which consisted of six livelihood components with several sub-components under each component. Primary data to construct the LVIs were collected through a semi-structed questionnaire survey of 132 households in a coastal polder. The survey data were triangulated and supplemented with qualitative data from focused group discussions and key informant interviews. The results showed significant rises in temperature in southwest coastal Bangladesh. Though there were no discernable trends in annual and seasonal rainfalls, the anomalies increased in the dry season. The annual PCI and Z were found to capture the climate variability better than the currently used mean monthly standard deviation. The comparison of the LVIs of the present decade with the past indicated that the livelihood vulnerability, particularly in the water component, had increased in the coastal polder due to the increases in natural hazards and climate variability. The index-based vulnerability analysis conducted in this study can be adapted for livelihood vulnerability assessment in deltaic coastal areas of Asia and Africa.

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