Climate change: challenges for agricultural environment. Рубрика в журнале - Региональные проблемы
Ammonia-oxidizing bacteria respond to multifactorial global change
Статья научная
In many recent studies, the effects of climate change on the future of biodiversity have been studied. As a result of human economic activity, extraction of mineral resources, land-use management, application of fertilizers (for example, nitrogen-containing compounds), carbon dioxide emissions into the Earth's atmosphere increase. This causes a change in the air temperature in the direction of increase and a change in the quantity and quality of the sediments, causing a wetting of the soils. The reaction of bacteria capable of oxidizing ammonia, belong to the group of chemo-litho-autotrophic microorganisms and at the same time are not associative microflora, was studied. In both natural and human-induced disturbance altered ecosystems, they strongly depend on these bacteria through intensive oxidation of ammonium. In response to artificially created climate changes, we received a change in the structure of the ammonium-oxidizing bacteria (AOB) community. The addition of a large amount of nitrogen fertilizer has led to a change in the number of bacteria that oxidize ammonia, while the temperature and humidity levels have changed, which also have an impact on AOB...
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Статья научная
Strontium (Sr) and Vanadium (V) are potentially dangerous for the natural environment. Little is known about the accumulation and mobility thought soils profiles of different Sr and V forms. Several studies of Sr and V distribution in soils have demonstrated strongly fixation of elements by different soil properties. Climate change and, respectively, soils redox cycles changes can affect the main soil properties and of their associated elements. In current work, contents and the main factors controlling the vertical distribution and accumulation of total, “pseudo-total” and water soluble forms of Sr and V in the agricultural soils formed under long-term fertilizer application were studied. Total Sr and V contents increased to 10% and 2% respectively with adding fertilizer. The contents of “pseudo-total” Sr and V forms increased to 20%. The concentrations of water soluble Sr and V forms increased to 65%. The contents of Sr and V were manly controlled by soil acidity levels and organic C content in studied soils. Additionally, Sr was associated with Ca-, P-, Mn- containing compounds and V with Al-, Si-, Fe- containing compounds. Knowledge of the chemical behavior of the Sr and V in the agricultural soils creates a scientific basis for risk assessment and remediation strategies.
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Grassfire forecast at agricultural lands of the Jewish autonomous region
Статья научная
The method proposed for prediction of the grass fire ignition and development during spring-autumn fire period is based on the author’s probability model for prediction of wild fire ignition depending on natural and man-made conditions, and the Australian McArthur model for forecast of non-forest fire development. This method has been verified on fire data of 2015-2017 in the Jewish Autonomous Region. Calculations were done with the help of electronic maps of forest area quarters and the network of operational-territorial units (OTU) of the agricultural lands designed at 2.5 x 2.5 km cells. The Earth’s remote sensing data on non-forest fires in 2010-2014 and information on Normalized Difference Vegetation Index (NDVI) during periods before and after growing season (April 23 - May 13, and September 24 - October 10) are used. The highest probability of the fire effect on agricultural land is found at a distance of 3 km from the roads and 3-6 km from the urban areas. The spatial coincidence of OTU with real and predicted grassfires and the validity of the forecast in spring before growing season are considered to be satisfactory. The suggested method of predicting grassfire ignition and development has a considerable practical importance and can be applied in the development of fire-incident management strategies and measures to mitigate a threat to human and environmental health.
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Land reclamation and transformation of floodplain-channel complexes at the Middle Amur lowland
Статья научная
Due to the specifics of climate, geology and relief of the Russian Far East, extensive land reclamation has been carried out in this region for more than sixty years in order to create the necessary conditions for agricultural production. The purpose of this land reclamation is heavy soils drainage in Primorye and the Amur Region. An extensive network of reclamation systems of open and closed types was created. This paper presents the results of studying the effect of land reclamation on floodplain-channel complexes (FCC) of the Middle Amur Lowland. It was found that construction and subsequent operation of reclamation systems (water receivers, main canals, regulating dehumidifiers) led to general degradation of FCC with full cessation in development of channel and riverine forms at micro- and meso- relief, and their complete silting. The concentration and seasonal dynamics of heavy metals in the soils of meliorated lands, in bottom sediments and water of small rivers and main canals at FCC was estimated. The content of heavy metals in the soils of meliorated lands’ decreased in comparison with unaffected environment. At the same time, accumulation of heavy metals took place in the waters and bottom sediments of main canals and water receivers. In addition, the paper presents data on the impact of catastrophic and unfavorable hydrological phenomena (floods, freshets) on the dynamics and state of agrocenoses within the boundaries of FCC.
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Phenophase shifts across elevations on major mountains in North China
Статья научная
Previous studies have reported plant phenological changes along horizontal belts in North China, however, little is known about elevation effects on mountain phenophases in China, such as how vegetation phenophases shift across elevation on mountains, and how they change under background of global change. In this context, by application of remote sensing data, Moderate Resolution Imaging Spectroradiometer (MODIS), changes of spring phenophases across elevation on 6 typical mountains in North China, namely Wuling, Xiaowutai, Guandi, Migang, Huashan and Taibai Moutians, and the effects of elevation on phenophases along altitudinal gradients, were studied in current work. Preliminary results showed that, similar to our findings of phenological changes in plain area in North China, the onset of vegetation phenophases in spring advanced on these mountains, while the ending time for autumn phenophases delayed in the past two decades. Trends for advanced spring phenophase increased significantly with altitude in some mountain regions, and spring phenophase sensitivities to altitude are stronger in lower latitude than in higher latitude regions...
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Статья научная
The salinity level in the coastal ecosystem and agricultural lands is being increased gradually due to the climate change effect, and Bangladesh is no exception to suffer salinity intrusion threatening its food security. In order to bring the salinity-affected lands under agriculture, the application of salt-tolerant, plant growth-promoting rhizobacteria (PGPR) as biofertilizer could be a method of choice. The current research reports the isolation of a salt-tolerant PGPR, identified as Bacillus aryabhattai MS3 from a coastal rice field of Bangladesh. Under laboratory condition, the strain showed profound plant growth-promoting activities: nitrogen fixation, production of indole acetic acid (IAA), phosphorus solubilization and siderophore production under 200 mM salinity. While in soil, rice growth under non-saline condition was comparable in between biofertilizer-added and control pots, the scenario was statistically significant when challenged with salts, 46% and 8% survival were recorded respectively...
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Signs of climate change in Afghanistan: drought and its effect on agriculture
Статья научная
Afghanistan is one of the countries that have suffered the most damages from the change of climate. Over the recent decades, its temperature has increased and on the contrary, precipitation has decreased, with serious change in its special and temporal distribution. Decrease in the thickness and area of the avalanches, retreat of the snow line, decline of the ground water level, decrease of river flows, and shortage of potable water for humans, animals and irrigation are considered as other signs and effects of the climate change (CC). Occurrence of successive droughts, poverty, mass immigration, decrease of the price of cattle or their death, loss of rain-fed agriculture or its serious damage, decrease of the level of agricultural products, lack of food security, elimination of pastures, spread of human, animal and plant diseases, pollution of water, soil and air and tens of other cases have been continually caused due to the CC in Afghanistan. Although the part of Afghanistan has very little signs of the climate change, it suffers more than any other country. There are two solutions to decrease the effects of the CC in the country. First, to take preventive measures, or to be prepared before the occurrence of an incident and second, to coordinate life conditions with climate changes; all effects of the CC in Afghanistan should be considered.
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