The article summarizes the results of the first stage of research into adaptation measures taken by the rural population of mountain areas and the administration of Dagestan in response to climate ...change. An assessment of climate change over the past 20 years in the Eastern Caucasus, with special attention to the mountain areas of Dagestan, was carried out based on reanalysis data. It has been revealed that in the last decade in the midlands and highlands, annual and seasonal temperatures have increased significantly, and the amount of annual and summer precipitation has begun to decrease; in general, the mountains of the Eastern Caucasus and Dagestan, in particular, are becoming warmer and drier. Actions of mountain residents in the crop production in response to warming and increasing moisture deficit are mainly aimed, as in many other mountain rural regions of the world, at changing varieties and crops, growing intensive orchards that are more tolerant to climate change, and expanding the range of terraced fruit crops. The unpredictability of weather events has spurred the active growth of the greenhouse industry. New processes have intensified related industries and breeding science in Dagestan. The population’s initiatives are supported by the Program for the Socioeconomic Development of Mountain Areas of the Republic of Dagestan for 2020–2025, which provides subsidies and grants, primarily for small farms and personal subsidiary plots. The aim of the Program is not adaptation to climate change, but these measures are objectively manifested as support for the adaptation measures of the population. The mountain agricultural terraces of Dagestan are considered a potential resource for development of agriculture in the face of climate change, as well as possible tourism sites, representing elements of historical and cultural heritage and identity of local landscapes.
Conventional practices of nitrogen (N) and phosphorus (P) application were evaluated based on nutrient balance calculation and soil N and P level from 916 surveyed orchards in North China, in order ...to assess the potential environmental risks. The results showed that excessive N and P application was common, with the average input rates of 588.4 kg N ha⁻¹, and 156.7 kg P ha⁻¹, respectively, which were 2.5–3.0 folds higher than the fruit N and P demand. High proportions of surplus N and P were found in grape, apple, pear and peach orchards in the plain regions with high economic returns. Nitrogen surplus reduced soil carbon (C)/N ratio in the plain, plateau and mountain regions. High soil Olsen-P level in the 40% of surveyed orchards, predominantly distributed in grape and peach orchards, was over the environmental threshold. Controlling N and P fertilization is the key to maintain sustainable fruit production in North China.
An irrigation experiment was conducted during 5 years in two hedgerow olive orchards (C and L) cv. Arbequina in Central Spain. The control treatments (C1 and L1) were irrigated to maintain the ...“wetted bulb” near field capacity throughout the season. Three deficit-irrigation treatments were applied from shoot growth (April-May) until pit hardening (beginning of July) with water applications relative to control, C2, C3, C4 (50, 25, 0%) and L2, L3, L4 (40, 17, 0%), respectively. Treatments reverted to full irrigation after pit hardening. During the treatment period a series of phenological events occurs: bud break, shoot growth, flower differentiation, flowering, fruit set, fruit drop and pit hardening. Responses of vegetative growth, flowering, fruiting, fruit characteristics and production were evaluated through their relationships with midday stem water potential (Ψstem). Flowering was shown to be the most sensitive period to deficit irrigation and the major determinant of final production through reductions on fruit number and oil content. With high water during flowering (mean Ψstem before irrigation >−1.0 MPa) trees developed more nodes, leaves, fertile inflorescences and fruits per inflorescence with consequent high production (1278 kg oil ha−1). Oil production was significantly reduced (64% of maximum) when Ψstem was allowed to fall below −1.5 MPa at flowering and was halved at −1.7 MPa, reducing water productivity from 0.26 to 0.21 kg oil m−3. In contrast, Ψstem could be reduced to −1.8 MPa after flowering until pit hardening without effects on fruit drop, fruit size or oil content. Fruit drop increased when Ψstem from flowering until pit hardening was below −2.71 MPa. Fruit oil content at harvest was strongly related with fruit dry weight at pit hardening. Vegetative growth occurred continuously during spring, although mainly during flowering, and could not be reduced by deficit irrigation without reducing production. The results are advantageous to irrigation management in this and similar climatic regions where Spring is a critical period for olive production due to variable temperature, rainfall and crop water demand. They establish the high thresholds of Ψstem required to guide irrigation management during Spring without yield loss, and the substantial resulting loss when this threshold is exceeded. They also reveal that deficit irrigation strategies cannot be used in Spring to control canopy size in hedgerow orchard without serious impact on yield.
•Deficit irrigation from bud break until pit hardening affected vegetative growth, number of fruits and production.•During flowering the Ψstem must be greater than −1.5 MPa for higher components of yield production and water productivity.•From flowering to pit hardening the Ψstem should be maintained higher to −1.8 MPa, for high oil accumulation.•In high density orchards vegetative growth cannot be control during flowering without affecting production.
•This deficit irrigation during oil synthesis period did not affect vegetative growth, flowering, fruit set, fruit abscission.•Olive production decreased when the stem water potential decreases ...−1.82 MPa.•Oil production is affected when the stem water potential in the oil synthesis period decreases −2.21 MPa.•Maximum water productivity was achieved when the stem water potential was −2.31 MPa.
Although oil synthesis in fruits of cv. Arbequina starts at the end of pit hardening (beginning of July in central Spain) most oil is synthesized from late summer (end August) until harvest (end October). An experiment was established in two nearby high-density olive orchards (C and L) trained in 4-m spaced hedgerows (2.3 m tall) and maintained over three successive seasons (2011–2013) to determine the effect of irrigation treatments during oil synthesis on stem water potential (Ψstem), fruit characteristics, production, water productivity (production per irrigation amount + effective rainfall), flowering and fruit-set and next-year growth. The control treatments (C1 and L1) were irrigated to maintain the “wetted” bulb near field capacity throughout the season. Three deficit-irrigation treatments were established in each orchard. In orchard C, treatments C2, C3 and C4 received 64, 38, 14% of the water applied to C1, while in orchard L, treatments L2, L3 and L4 received 71, 41, 18% of water applied to L1. The treatments produced significant differences in Ψstem that were lower in Orchard C (mean C4 value −4.91 MPa) than L (L4 −2.58 MPa) due to differences in soil depth and drip emitter spacing. At the two orchards, individually, the stressed trees were not significantly affected in terms of shoot length, flowering, fruit set, fruit abscission and consequently fruit number. While deficit irrigation significantly reduced size, oil and water content of fruit, and hence olive and oil production in Orchard C, there was no response in Orchard L. Analysis revealed that individual fruit parameters were maintained constant as Ψstem decreased during oil synthesis in response to treatment until a threshold value was reached. Oil content (% fresh weight-FW) was the least sensitive parameter (threshold −4.11 MPa) with a positive linear relationship between water and oil fruit content (R2 = 0.81). Olive production was more sensitive to Ψstem (threshold −1.82 MPa) than oil production (−2.21 MPa). Indicating that moderate stress can be applied during oil synthesis by irrigating such that Ψstem declines to the threshold value −2.21 MPa without reduction of oil production. This value corresponds to a water-stress integral of 130 MPa day−1. Maximum water productivity was achieved by irrigating at Ψstem −2.31 MPa with lower values obtained at higher or lower Ψstem. Our results indicate that Ψstem should be maintained higher than −2.21 MPa during oil synthesis for maximum production, but higher values of the water productivity will be achieved at −2.31 MPa.
•A countrywide survey elucidated major reasons for high acidity in olive oil.•Geographic and environmental factors had no significant effect on oil acidity.•Low fruit yield (<20kgtree−1) was firmly ...associated with high oil acidity.•High oil acidity evolved particularly from fungus-infected, fully ripened fruit.•Selective harvesting or fruit sorting may help meet EVOO standards.
Olive oil quality has become a foremost revenue-determining parameter for olive growers. While the upper threshold of oil acidity, a major quality standard of extra-virgin olive oil (EVOO), is under pressure of being reduced to below 0.8% of free fatty acids (FFA), excessive oil acidity is a frequent phenomenon, raising considerable economic concerns. Despite the many assumptions regarding the origins of FFA in olive oil, there is no concrete understanding upon which to base practical solutions. The objective of the present study was to identify the major actual reasons for excess oil acidity in a 2-year (2011–2012) countrywide survey that included 25 olive orchards of the Barnea variety. In each location, orchard management and environment were characterized, and the fruit of selected trees with specified fruit loads were sampled. Each sample underwent comprehensive analyses for fruit size, ripening index, oil and water content, incidence of insect damage and fruit rot, tree mineral nutrient status, and parameters of oil quality. Whereas geographic and environmental factors had no significant effects, excessive oil acidity was strongly associated with low fruit load (<20kgtree−1) and advanced ripening index. High N concentration in fruit was also associated with high oil acidity. Further investigations revealed a particular segment of the fruit population accounting for most of the excess FFA values: large, fully ripened, fungus-infected fruit from low-yielding trees. It appears that in-orchard unsynchronized alternate bearing leads to significant diversity of the fruit population. Consequently, mature fruit of low-yielding trees harvested too late in the season are prone to fungal infections that may have adverse effects on oil quality. Keeping this hazardous segment of produce away from the olive press might help maintain oil acidity below the desired threshold.
This study presents an evaluation of soil organic carbon (SOC) and stock (SOCstock) for the whole rooting depth (60 cm), spaced 55 months in two adjacent olive orchards with similar conditions but ...different tree densities: (i) intensive, planted in 1996 at 310 tree ha−1; (ii) superintensive, planted in 2000 at 1850 tree ha−1. This was carried out to test the hypothesis that olive orchards at different plant densities will have different rates of accumulation of SOC in the whole soil rooting depth. SOC increased significantly in the superintensive orchard during the 55-month period, from 1.1 to 1.6% in the lane area, and from 1.2 to 1.7% in the tree area (average 0–60 cm), with a significant increase in SOCstock from 4.7 to 6.1 kg m−2. In the intensive orchard, there was not a significant increase in SOCstock in 0–60 cm, average of 4.06 and 4.16 kg m−2 in 2013 and 2018, respectively. Results indicate a potential for a significant increase in SOC and SOCstock in olive orchards at higher tree densities when combined with temporary cover crops and mulch of chopped pruning residues. The increase is associated with an increase in SOC, mainly at a 0–15 cm depth. Results also point to the need for improve our monitoring capabilities to detect moderate increases in SOC.
•Daily sap flow rate and monthly water uptake of sweet cherry trees were estimated.•Sap flow ranged in fifth leaf 10–40, in eighth leaf 40–60lday−1 from May to August.•Crop basal coefficient varied ...between 0.4 and 0.9 depending on the phenological course.
Sapflow was measured applying heat balance method on sample trees of a high density (spacing 4m×2m) orchard between the age of 4–7 years from 1 of May to 31 of August each year (2008, 2009, and 2011). Data from different 162 sample days were used in calculation of water consumption of sample trees and orchard. An automatic weather system was installed at the sweet cherry plantation to measure meteorological variables. The average daily water uptake of the 4-year-old trees were 24.2, 23.6, 22.7, and 10.9l from May to August in 2008, while in 2011 the 7-year-old trees transpirated in May 55.6, in July 48.4 and in August 44.8l per day. We found that the transpiration of trees in 4- and 5-year-old intensive sweet cherry orchard were 305mm and 320mm. The cumulative transpiration reached 523mm for 3 months in 2011, while for the whole vegetation period 700–800l water requirement can be calculated for local condition in intensive sweet-cherry orchards. The sapflow course showed typical characteristics on the investigated days with different weather conditions. The intensive water uptake began at about 6:00a.m. and slowed down to minimum between 20:00 and 22:00p.m. Transpiration of trees showed strong correlation to vapor pressure deficit, global radiation and air temperature, independently from the available precipitation. The crop basal coefficient (Kcb) – calculated as the rate of tree transpiration measured by SF and the referenced evapotranspiration – varied between 0.4 and 0.9. Our research results can contribute to harmonize the water supply and the plant's water use, and planning the irrigation.
Pheromone traps were used to monitor the following tortricid moths, i.e. Adoxophyes orana, Archips podanus, A. rosanus, Hedya nubiferana, Pandemis heparana, Spilonota ocellana, Cydia pomonella, Cydia ...funebrana and Cydia molesta in the localities Brno-Tuřany (Brno-město), Nebovidy (Brno-venkov) and Prakšice (Uherské Hradiště). Other Lepidoptera non-target species were present in these target-species pheromone traps, i.e. Adoxophyes orana, Agrotis segetum, Amphipoea oculaea, Archips rosanus, Celypha striana, Cydia coronillana, Enarmonia formosana, Epiblema scutulanum, Epinotia huebneriana, Eucosma fervidana, Euxoa tritici, Hedya pruniana, H. nubiferana, Lymantria dispar, Noctua pronuba, Notocelia rosaecolana, N. roborana, Pammene albuginana, P. suspectana, Pandemis cerasana, Pyrausta rectefascialis, P. aurata, Spilonota ocellana, Yponomeuta malinellus and Zygaena purpuralis.
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