BACKGROUND: Pandemics as health and humanitarian crises have exerted traceable impacts on food security. Almost all past and current pandemics have created a food crisis that affects a share of the global population and threaten global food security. With the more frequent outbreaks of emerging and re-emerging diseases or pandemics, this paper looks at the various types of impacts from the current coronavirus crisis and past pandemics to identify their major impact on food security. SCOPE: To this effect, key strategies that could be put in place to ensure the efficient resilience of food systems before, during, and after the pandemics to mitigate the negative impact of the pandemics on global food security are recommended. The most recent effects of the current coronavirus crisis have been disruptions in the flow of farm labourers and inefficient farm operations leading to postharvest food losses. KEY FINDINGS AND CONCLUSIONS: Modification of diets between social groups has also been observed. Future response orientations to prevent and mitigate the effects of pandemics on food security will consider pro-active and adapted policy, program, and institutional actions towards the systemic development of global food systems as an interconnected network.
- MeSH
- COVID-19 * epidemiologie MeSH
- epidemický výskyt choroby MeSH
- lidé MeSH
- pandemie prevence a kontrola MeSH
- SARS-CoV-2 MeSH
- zajištění potravin MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Browsers represent a challenge for breeding facilities because of their sensitivity to nutritional management. Western Derby eland (Tautrotragus derbianus derbianus, WDE) is a large browsing antelope with a very diverse diet. Because of its critically endangered status, a small WDE population is kept for conservation purposes in the fenced Fathala reserve (Senegal) and during the critical, hot dry season, the animals are offered supplementary Acacia albida pods. We aimed to identify which woody plant species were preferentially selected/avoided by WDE during the period of food shortage, which plant nutritional properties were drivers of animals' diet selection, and how this selectivity was affected by supplemental feed. The animals were selective for certain plant species, most for Piliostigma thonningi pods. Preferences decreased with a feed supplement, while avoidances remained intact. Diet selection was connected with chemical traits, mostly by negative correlations to N, Mg, Ca and hemicellulose, which disappeared or were weaker when supplemental feed was offered. Our findings indicate that large browsers during periods of food shortage must cope with inappropriate chemical composition in regard to nutrition and seek to alleviate them not only by diversification of plant species in the diet, but also by adjusting chemical diet quality as a whole.
- MeSH
- antilopy fyziologie MeSH
- chov MeSH
- dieta * MeSH
- fyziologický stres MeSH
- fyziologie výživy zvířat MeSH
- krmivo pro zvířata analýza klasifikace MeSH
- ohrožené druhy MeSH
- preference v jídle * MeSH
- rostliny klasifikace metabolismus MeSH
- zachování přírodních zdrojů metody MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Senegal MeSH
Plant variation in nutrient concentrations encompasses two major axes. The first is connected to nitrogen (N) and phosphorus (P), reflects growth rate and has been designated as the leaf economics spectrum (LES) while the second follows the gradient in calcium (Ca) and magnesium (Mg) and mirrors cell structural differences. Here, we tested in grasslands whether the sum Ca + Mg concentrations is a better indicator of digestibility than LES constituents. Structural equation modelling revealed that the total effect size of N (0.30) on digestibility was much lower than that of Ca + Mg (0.58). The N effect originated predominantly from sampling date (biomass ageing), while the Ca + Mg effect largely from phylogenetic composition (proportion of monocots). Thus, plant variation in partially substitutable divalent cations seems to play a significant role in biomass digestion by ruminants. This finding contests, together with litter decomposition studies, the prominent role of the LES for understanding both fundamental ecological processes.
Crop rotation long-term field experiments were established in 1955 and 1956 at three locations in the Czech Republic (Čáslav, Ivanovice, and Lukavec) differing in their climatic and soil physicochemical properties. The effect of long-term application of farmyard manure and farmyard manure + NPK treatments on plant-available, easily mobilizable, potentially mobilizable, and pseudo-total contents of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) contents in soils (in 2013) as well as the uptake of these elements by winter wheat (Triticum aestivum L.) grain and straw were analyzed in the two following seasons: 2012 and 2013. The treatments resulted in increasing the soil pH level when compared to the control, but the cation exchange capacity remained unchanged. Although all fertilizers were applied for six decades, the pseudo-total concentration elements in both the soil and wheat plants stayed far below those of the Czech and European threshold limits for agricultural soils and cereals for human nutrition and feedstuff. Although the mobile pools of As, Cu, and Zn were slightly changed at the treated soils, these changes were not related to the element uptake by the wheat plants. Moreover, the effect of the location and growing season was more decisive for the differences in soil and plant element contents than for the individual treatments. Thus, the long-term application of farmyard manure did not result in any substantial change in risk element contents in both soils and winter wheat plants.
- MeSH
- hnůj * MeSH
- koncentrace vodíkových iontů MeSH
- látky znečišťující půdu analýza metabolismus MeSH
- lidé MeSH
- průmyslová hnojiva MeSH
- pšenice metabolismus MeSH
- půda chemie MeSH
- riziko MeSH
- těžké kovy analýza metabolismus MeSH
- zemědělství MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Fast-growing clones of Salix and Populus have been studied for remediation of soils contaminated by risk elements (RE) using short-rotation coppice plantations. Our aim was to assess biomass yield and distributions of elements in wood and bark of highly productive willow (S1--[Salix schwerinii × Salix viminalis] × S. viminalis, S2--Salix × smithiana clone S-218) and poplar (P1--Populus maximowiczii × Populus nigra, P2--P. nigra) clones with respect to aging. The field experiment was established in April 2008 on moderately Cd-, Pb- and Zn- contaminated soil. Shoots were harvested after four seasons (February 2012) and separated into annual classes of wood and bark. All tested clones grew on contaminated soils, with highest biomass production and lowest mortality exhibited by P1 and S2. Concentrations of elements, with exception of Ca and Pb, decreased with age and were higher in bark than in wood. The Salix clones were characterised by higher removal of Cd, Mn and Zn compared to the Populus clones. Despite generally higher RE content in young shoots, partly due to lower wood/bark ratios and higher RE concentrations in bark, the overall removal of RE was higher in older wood classes due to higher biomass yield. Thus, longer rotations seem to be more effective when phytoextraction strategy is considered. Of the four selected clones, S1 exhibited the best removal of Cd and Zn and is a good candidate for phytoextraction.
- MeSH
- biodegradace MeSH
- biomasa MeSH
- dřevo metabolismus MeSH
- kůra rostlin metabolismus MeSH
- látky znečišťující půdu metabolismus MeSH
- Populus metabolismus MeSH
- prvky MeSH
- regenerace a remediace životního prostředí * MeSH
- Salix metabolismus MeSH
- těžké kovy metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND AND AIMS: High Al resistance of Rumex obtusifolius together with its ability to accumulate Al has never been studied in weakly acidic conditions (pH > 5.8) and is not sufficiently described in real soil conditions. The potential elucidation of the role of organic acids in plant can explain the Al tolerance mechanism. METHODS: We established a pot experiment with R. obtusifolius planted in slightly acidic and alkaline soils. For the manipulation of Al availability, both soils were untreated and treated by lime and superphosphate. We determined mobile Al concentrations in soils and concentrations of Al and organic acids in organs. RESULTS: Al availability correlated positively to the extraction of organic acids (citric acid < oxalic acid) in soils. Monovalent Al cations were the most abundant mobile Al forms with positive charge in soils. Liming and superphosphate application were ambiguous measures for changing Al mobility in soils. Elevated transport of total Al from belowground organs into leaves was recorded in both lime-treated soils and in superphosphate-treated alkaline soil as a result of sufficient amount of Ca available from soil solution as well as from superphosphate that can probably modify distribution of total Al in R. obtusifolius as a representative of "oxalate plants." The highest concentrations of Al and organic acids were recorded in the leaves, followed by the stem and belowground organ infusions. CONCLUSIONS: In alkaline soil, R. obtusifolius is an Al-hyperaccumulator with the highest concentrations of oxalate in leaves, of malate in stems, and of citrate in belowground organs. These organic acids form strong complexes with Al that can play a key role in internal Al tolerance but the used methods did not allow us to distinguish the proportion of total Al-organic complexes to the free organic acids.
- MeSH
- analýza hlavních komponent MeSH
- biologický transport MeSH
- hliník farmakokinetika MeSH
- koncentrace vodíkových iontů MeSH
- kyselina citronová metabolismus MeSH
- kyselina octová metabolismus MeSH
- kyselina oxalová metabolismus MeSH
- látky znečišťující půdu farmakokinetika MeSH
- molekulová hmotnost MeSH
- půda chemie MeSH
- Rumex účinky léků metabolismus MeSH
- tkáňová distribuce MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Polyploidy and increased genome size are hypothesized to increase organismal nutrient demands, namely of phosphorus (P), which is an essential and abundant component of nucleic acids. Therefore, polyploids and plants with larger genomes are expected to be selectively disadvantaged in P-limited environments. However, this hypothesis has yet to be experimentally tested. We measured the somatic DNA content and ploidy level in 74 vascular plant species in a long-term fertilization experiment. The differences between the fertilizer treatments regarding the DNA content and ploidy level of the established species were tested using phylogeny-based statistics. The percentage and biomass of polyploid species clearly increased with soil P in particular fertilizer treatments, and a similar but weaker trend was observed for the DNA content. These increases were associated with the dominance of competitive life strategy (particularly advantageous in the P-treated plots) in polyploids and the enhanced competitive ability of dominant polyploid grasses at high soil P concentrations, indicating their increased P limitation. Our results verify the hypothesized effect of P availability on the selection of polyploids and plants with increased genome sizes, although the relative contribution of increased P demands vs increased competitiveness as causes of the observed pattern requires further evaluation.
- MeSH
- délka genomu * MeSH
- DNA rostlinná MeSH
- fosfor metabolismus MeSH
- genom rostlinný * MeSH
- lipnicovité genetika MeSH
- molekulární evoluce * MeSH
- polyploidie * MeSH
- průmyslová hnojiva * MeSH
- půda chemie MeSH
- rostliny genetika MeSH
- selekce (genetika) MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Current plant--herbivore interaction models and experiments with mammalian herbivores grazing plant monocultures show the superiority of a maximizing forage quality strategy (MFQ) over a maximizing intake strategy (MI). However, there is a lack of evidence whether grazers comply with the model predictions under field conditions. METHODOLOGY/FINDINGS: We assessed diet selection of sheep (Ovis aries) using plant functional traits in productive mesic vs. low-productivity dry species-rich grasslands dominated by resource-exploitative vs. resource-conservative species respectively. Each grassland type was studied in two replicates for two years. We investigated the first grazing cycle in a set of 288 plots with a diameter of 30 cm, i.e. the size of sheep feeding station. In mesic grasslands, high plot defoliation was associated with community weighted means of leaf traits referring to high forage quality, i.e. low leaf dry matter content (LDMC) and high specific leaf area (SLA), with a high proportion of legumes and the most with high community weighted mean of forage indicator value. In contrast in dry grasslands, high community weighted mean of canopy height, an estimate of forage quantity, was the best predictor of plot defoliation. Similar differences in selection on forage quality vs. quantity were detected within plots. Sheep selected plants with higher forage indicator values than the plot specific community weighted mean of forage indicator value in mesic grasslands whereas taller plants were selected in dry grasslands. However, at this scale sheep avoided legumes and plants with higher SLA, preferred plants with higher LDMC while grazing plants with higher forage indicator values in mesic grasslands. CONCLUSIONS: Our findings indicate that MFQ appears superior over MI only in habitats with a predominance of resource-exploitative species. Furthermore, plant functional traits (LDMC, SLA, nitrogen fixer) seem to be helpful correlates of forage quality only at the community level.
- MeSH
- biomasa MeSH
- býložravci fyziologie MeSH
- dieta MeSH
- druhová specificita MeSH
- ekosystém * MeSH
- kvantitativní znak dědičný * MeSH
- lineární modely MeSH
- lipnicovité fyziologie MeSH
- ovce fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
An experiment to reveal functional response and heifers' performance to sward characteristics and forage chemical composition was conducted for 5 years in rotational (RSS) and continuous (CSS) stocking systems on native species-rich upland grassland. We measured sward characteristics, forage chemical composition, heifers' grazing behavior and live-weight gains from July to September. Mean sward surface height was lower on CSS than on RSS; grass and forb density, and white clover stolon length, were similar. Herbage on CSS had higher crude protein content and lower crude fiber content than on RSS. No difference existed in time budgets of grazing, ruminating and resting between stocking systems and season, while grazing rates were higher on CSS. Stocking rate was 1671 and 1332 kg per ha on CSS and RSS, individual daily live-weight gain 683 and 652 g on CSS and RSS. Gain per ha was 20 kg higher on CSS. Results suggested stocking systems on native species-rich grassland had no effect on activity time budgets or animal performance. Both RSS and CSS allow similar outputs for stocking rates in terms of individual daily live-weight gain. Key parameters determining heifers' behavior and performance were sward height, grass and forb density in the sward, and content of crude fiber and protein in forage.
In their recent study, Borowicz and Armstrong (Oecologia 169:783-792, 2012) investigated effects of nutrient availability and competition for light on a perennial root hemiparasite Pedicularis canadensis. Their study showed a reduction of community productivity as a result of hemiparasite infection independently of a clear positive effect of increased nutrients. In contrast, there was a minimal effect of increased competition for light on growth of the parasite. Here, we summarize the available data on the influence of nutrient availability (closely related to productivity) on temperate grassland root hemiparasites thus expanding the discussion presented by Borowicz and Armstrong (Oecologia 169:783-792, 2012). Most studies show that root hemiparasites are highly sensitive to elevated competition for light in productive environments, which is manifested as an increase in mortality coupled to a decrease in population density. Such responses reflect increased mortality of hemiparasite seedlings that are physiologically inefficient in terms of photosynthesis and nutrient acquisition owing to a limited root network and consequently, are highly sensitive to competition for light. However, the susceptibility of hemiparasites to competition for light tends to decrease for individuals that survive the critical seedling stage. Moreover, survivors benefit from elevated nutrient availability, resulting in increased growth and fecundity. Elevated productivity can thus have opposing effects on the survival and growth of hemiparasites depending on life stage. We conclude that the findings by Borowicz and Armstrong (Oecologia 169:783-792, 2012) are not in conflict with this general view that root hemiparasite population ecology is strongly influenced by competition for light in highly productive environments.
