Irrigated Plots Research Articles

Applying poultry manure and irrigation in cultivating potatoes in the southern forest-steppe of the Bashkortostan Republic

The goal of this research is to determine the effect of poultry manure and irrigation on the yield and quality of potatoes (Solanum tuberosum) grown in fields located on the southern steppe of the Republic of Bashkortostan. Before the poultry manure was added, it was treated with a microbiological fertilizer to suppress pathogenic microflora. Potato tubers were pretreated with an insectofungicide to avoid infestation. During vegetation, potato leaves and tubers were studied at the stage of the full blossom, leaves’ decay and potato harvest. The results showed tuber yields with the application of pretreated poultry manure to be 120 t/ha, both on the rainfed and irrigated plots (from 0.23 to 0.82 kg/plant and from 0.24 to 1.02 kg/plant, respectively). On the rainfed and irrigated plots where poultry manure was not applied (control fields), the tubers’ weight ranged from 0.08 to 0.31 kg/plant and from 0.16 to 0.5 kg/plant, respectively. Along with this, poultry manure utilization also affected the starch content of potatoes—it ranged from 12.9% (for irrigated plots with 80 t/ha poultry manure applied) to 19.2% (for rainfed plots without fertilizers). Laboratory analyses revealed that the nitrate content increased from 171.80 to 232.98 mg/kg on rainfed plots (depending on the introduced amount of poultry manure) and by 7.91%–15.19% on irrigated plots. Upon application of 40 t/ha of manure, under irrigation, the highest marketable value of tubers was 78%. On the rainfed plots, the same value was 72% when applying poultry manure at a dose of 120 t/ha.

Influence of Different Crop Establishment and Irrigation Methods on Growth and Growth Indices of Rice

The increasing global demand for water in many sectors has become a universal concern. Challenge is to develop advanced production systems that allow rice production to be sustained in the face of waning water availability. With the intention to find the efficient water saving technology and establishment method, a field experiment was conducted at Zonal Agricultural Research Station, V. C. Farm, Mandya, University of Agricultural Sciences, and Bangalore during Kharif 2018. The experiment was laid out in split plot design with three main plot irrigation treatments and five sub plot rice establishment treatments. The paddy variety used was ‘MTU 1001’. Objective was to study the irrigation and establishment methods on growth of rice. The results revealed that, continuous flooding recorded significantly higher plant height (80.67 cm) at harvest. Whereas, alternate wetting and drying (AWD) recorded higher leaf area index (5.06), CGR at 30 to 60 DAS, 60 to 90 DAS and 90 DAS to harvest (1.49, 3.50 and 2.47 g m-2 day-1, respectively), NAR at 30 to 60 DAS and 60 to 90 DAS (7.19 and 4.37 mg cm-2 day-1, respectively). Among establishment methods, manual transplanting recorded higher plant height (81.82 cm), LAI (5.70), DME (55.77), AGR at 30 DAS (0.36 g day-1), CGR at 30 to 60 DAS and 60 to 90 DAS (1.73 and 3.94 g m-2 day-1, respectively) and LAD at 30 to 60 DAS, 60 to 90 DAS and 90DAS to harvest (49.50, 128.70 and 272.80, respectively). However, mechanical transplanting recorded significantly more number of tillers m-2 (765.67), NAR at 30 to 60 DAS and 60 to 90 DAS (9.96 and 4.41 mg cm-2 day-1, respectively). AWD method of irrigation in mechanical transplanting and manual transplanting are found to be better among all other methods due to the higher growth and development.

Utilization of poultry manure when cultivating potatoes in the southern steppe of the Republic of Bashkortostan

The goal of the research is to determine the effect of pretreated poultry manure and irrigation on the yield and quality of potatoes (Solanum tuberosum) grown in fields located on the southern steppe of the Republic of Bashkortostan. Field experiments were repeated every three years. During vegetation, potato leaves and tubers were studied at the full blossom, leaves’ decay, and potato harvest. The results showed that applying pretreated poultry manure at the rate of 120 t/ha favored higher tuber weight both on the rainfed and irrigated plots (from 0.23 to 0.82 kg/plant and from 0.24 to 1.02 kg/plant, respectively). On the rainfed and irrigated plots where poultry mature was not applied (control fields) the tubers’ weight ranged from 0.08 to 0.31 kg/plant and from 0.16 to 0.50 kg/plant, respectively. Upon application of 40 t/ha of manure, under irrigation, the highest marketable value of tubers was 78%. On the rainfed plots the same value was 72% when applying poultry manure at a dose of 120 t/ha. Soil moisture monitoring showed that the potatoes did not get adequate water during the growing season. When the soil moisture on irrigated plots was 70% less than its minimum water capacity, potato plantings were watered.

Influence of irrigation and hydrogel application on yield and economics of pearl millet (Pennisetum glaucum L.) under Eastern UP condition

An experiment was conducted at CRF (Crop Research Farm), Department of Agronomy, SHUATS, Prayagraj, (U.P.) during Zaid crop season 2020. The soil of site was sandy loam in texture with neutral PH. The experiment was carried out in split plot design having nine treatment consisted of main plot Irrigation viz., I1 (2 Irrigation during Emergence and Early Tillering), I2 (3 Irrigation during Emergence, Early Tillering and Boot stage) and I3 (4 Irrigation during Emergence, Early Tillering, Boot stage and Grain filling) and sub plot, Hydrogel viz., H0 (0 kg/ha), H1 (2 kg/ha) and H2 (4 kg/ha) which are replicated thrice and effect was observed on Manipuri variety of Bajra. The result indicated that increase in irrigation interval and hydrogel significantly improved yield attributes and yield. At, harvesting, 4 irrigation recorded maximum of Grain yield (1.88 t/ha), Stover yield (4.31 t/ha) and Harvest index (30.24 %) hydrogel also resulted significantly higher Grain yield (1.98 t/ha), Stover yield (4.44 t/ha) and Harvest index (30.79 %) Maximum Gross return (69222.96/ha), Net return (45066.76/ha) and Benefit to Cost ratio (2.87) were recorded by application of 4 kg/ha hydrogel with 4 irrigation.

Risk of heavy metals accumulation in soil and wheat grains with waste water irrigation under different NPK levels in alkaline calcareous soil.

A field study was conducted on the reuse of wastewater from Mardan city to evaluate its risk of contaminating soil and wheat grains at different NPK levels. Three irrigation sources i.e. waste water (WW), canal water (CW) and alternate waste + canal water (WW+CW) were applied to wheat (cv Atta Habib 2010) grown at 0, 50, 75 and 100% NPK levels of 120:90:60 kg N:P2O5:K2O ha-1 at Palatoo Research Farm, Amir Muhammad Khan Campus, Mardan during 2015.The results showed higher grain and biomass yields in WW irrigated plots as compared to CW at NPK levels up to 50% of recommending dose revealing supplementing nutrient requirements in deficient conditions. However, irrigation of WW at higher NPK levels especially at or beyond 75% of recommended dose tended to reduce the crop yield that could be associated with heavy metals toxicity and nutritional imbalances. The use of WW substantially increased AB-DTPA extractable Zn, Mn, Pb, Ni and Cd indicating a potential threat to soil contamination. Similarly, WW irrigated wheat had higher concentrations of these heavy metals as compared to CW which limits its use for production purposes without any remediation measures. The alternate use of CW and WW as revealed by its comparative lower contamination in soil and wheat than sole WW could be one of the possible solutions and may increase the time required for threshold soil contamination.

Adoption of multiple sustainable land management practices among irrigator rural farm households of Ethiopia

AbstractUsing a household and plot‐level survey conducted in Ethiopia, this study analyses the difference in farmers' adoption of sustainable land management (SLM) practices between their rainfed and irrigated plots. The paper also investigates the varying influence of different types of irrigation water management systems and associated irrigation technologies on the adoption of SLM practices in irrigated plots. After controlling for heterogeneity among different irrigation water management systems and technologies, we found that access to irrigation play major role in enhancing farmers' motivation to adopt more SLM practices. Furthermore, the combined effect of irrigation water management system and irrigation technology on type and number of SLM practices adopted is quite varied and very significant. The evidence highlights that farmers adopt more SLM practices in their plots with pump irrigation compared with those plots where gravity irrigation is applied because pump irrigation systems enhance complementarities with SLM practices. Finally, the findings underscore that the type of irrigation water management and the irrigation technology applied play an important role in restoring degraded lands and maintaining soil fertility, even when farmers' adoption of irrigation was not explicitly triggered by concerns for soil health.

Fruit Yield, Polyphenols, and Carotenoids in Long Shelf-Life Tomatoes in Response to Drought Stress and Rewatering

The Mediterranean long shelf-life tomato (or long storage tomato) is a plant traditionally cultivated under no irrigation in the Southern regions of Italy, whose fruits have typical high sensory and nutritional quality. However, yield levels are kept low under current cultivation conditions. In this study, the effects of repeated cycles of drying and rehydration on crop productivity and nutritional quality of fruits in terms of polyphenols and carotenoids content were assessed in long shelf-life tomatoes cultivated in a typical semi-arid area of Southern Italy. The three local Sicilian landraces ‘Custonaci’, ‘Salina’ and ‘Vulcano’, and the commercial tomato hybrid ‘Faino’ (control) were submitted to three irrigation treatments: DRY (no irrigation); IRR (long-season full irrigation); REW (drought/rewatering cycles). Total 450, 4710, and 1849 m3 ha−1, were distributed in DRY, IRR, and REW, respectively. At harvest, fruit yield, polyphenols (as total, flavonoids, and hydroxycinnamoyl quinic acids-HCQA), and carotenoids contents (lycopene and β-carotene) were measured. All cultivars benefitted from very limited irrigation in REW, raising their productivity (up to +147% in ‘Vulcano’) with respect to that of plants overstressed in DRY. Irrigation water use efficiency in REW was higher than that in IRR. Water shortage in REW led to a polyphenols content of fruits that was slightly lower (171.1 μg g−1) than that in DRY, but higher than that in IRR (116.8 μg g−1). All local landraces had greater contents (>160 μg g−1) than control (113.0 μg g−1). Under REW and DRY, the two landraces ‘Salina’ and ‘Vulcano’ produced fruits with the same polyphenols and flavonoids contents. Overall, the two water stressed treatments (DRY and REW) did not differ for HCQA content (>66 μg g−1), which was significantly higher than that in the irrigated plots (<50.55 μg g−1). Lycopene content in DRY and REW exceeded 100 μg g−1; among local types, ‘Vulcano’ exhibited the highest content (106.7 μg g−1). The β-carotene content did not change in ‘Custonaci’ and ‘Salina’, whereas in ‘Vulcano’ it was greater in DRY and REW. Only in ‘Faino’ water limitation in REW exerted a clear promoting effect on β-carotene content of fruits. The results of the present study reveal how rewatering after long-lasting drought periods is beneficial to long shelf-life tomatoes in terms of productivity. Appropriate drought cycles in REW may also help the fruits to retain high nutritional levels.

The Biological Parameters as an Indicators of Water Quality for a Tourism Area Spot in Jurang Sate Primary Canal Central of Lombok, Indonesia

Jurang Sate primary canal is one of the the main irrigation canal in central Lombok which supplies water from the main network, namely Jangkok, Sesaot, and Keru Feeder weir to several secondary canal and to irrigated tertiary plots. The local community use the Jurang Sate Primary canal in a variety of daily activities, and nowadays it is used as a means of water tourism. The purpose of this study was to determine the water quality for ectourism area spot of the Jurang Sate primary canal based on biological parameters, namely the total Coliform bacteria, and the diversity of phytoplankton species. Measurement of coliform bacteria parameters and phytoplankton diversity was carried out ex-situ. The results showed that the total Coliform bacteria count in each sample calculated with MPN index was in the range of 170-110000 MPN/100 ml. The phytoplankton identified in this study were 24 species, 15 orders, and 6 classes. Phytoplankton species diversity index value of 1.32 (medium category). The water of the primary channel of Jurang Sate was categorized in moderately polluted. The conclusion of this research is the water of the Jurang Sate primary canal is not ideal for water tourism activity.

Analysis of Weather-Related Growth Differences in Winter Wheat in a Three-Year Field Trial in North-East Germany

Winter wheat is the most important crop in Germany, which is why a three-year field trial (2015–2017) investigated the effects of weather on biometric parameters in relation to the phenological growth stage of the winter wheat varieties Opal, Kerubino, Edgar. In Brandenburg, there have been frequent extreme weather events in the growth phases that are relevant to grain yields. Two winter wheat varieties were grown per trial year and parts of the experimental field areas were irrigated. In addition, soil physical, biometric and meteorological data were collected during the growing season (March until end of July). There were five dry periods in 2015, six in 2016, and two in 2017 associated with low soil moisture. Notably, in 2016 the plant height was 5 cm lower and the cover was 15% lower than on irrigated plots. The grain yield was increased by 19% and 31% respectively by irrigation. However, due to irrigation costs, the net grain yield on irrigated plots was lower than on the unirrigated plots. It turned out that in dry years there were hardly any differences between winter wheat varieties. Multiple regression analysis showed a strong correlation between the biometric parameters considered here and the grain yield.

REUTILIZAÇÃO DA ÁGUA RESIDUÁRIA DA ORDENHA NA PALMA SOB DIFERENTES FREQUÊNCIAS DE IRRIGAÇÃO E ADUBAÇÃO

Objetivou–se avaliar o desempenho da palma miúda (Nopalea cochenillifera Salm Dyck), em cultivo adensado sob diferentes frequências de fertilização e irrigação com água de reuso no semiárido sergipano. O delineamento foi em parcelas subdivididas, com três repetições de quatro parcelas de irrigação (7, 14, 21 e 28) e um controle (sem irrigação) e quatro níveis de fertilização: adubação orgânica 1 (35t esterco bovino ha-1), adubação orgânica 2 (35t esterco ovino ha-1), química (150 kg de N ha-1) e fertirrigação (água residuária). Onde as variáveis de crescimento (Altura, TCV-Taxa de Crescimento Vertical; TCH-Taxa de Crescimento Horizontal; TApC-Taxa de Aparecimento de Cladódio) não demonstraram diferenças em relação a frequencia de irrigação com o controle; os NCT-Números de Cladódios Totais, o CC-Comprimento do Cladódio, EC- Espessura do Cladódio, VT- Volume Total e a EUA- Eficiência de Uso da Água, foram semelhantes entre os tratamentos e a LC-Largura do cladódio foi inversamente proporcional; frequências de irrigação de 7 e 14 dias foram semelhantes e maiores que 21 e 28 dias. No tratamento controle (sequeiro) obteve - se produtividade de 23,84 t MS ha-1, sendo a menor obtida quando comparada a maior produtividade da frequência de irrigação de 14 dias, que foi de 30,11 t MS ha-1. A frequência de irrigação de 7 dias promoveu melhores resultados morfológicos na palma. Podendo inferir que, aos 18 meses de idade, se o fator água não for limitante, a palma miúda pode atingir o ponto máximo de crescimento, sendo este, quando atingida a 5ª ordem de aparecimento de cladódios.

Dwarf and Tall Elephantgrass Genotypes under Irrigation as Forage Sources for Ruminants: Herbage Accumulation and Nutritive Value.

Simple SummaryCyclical droughts negatively impact agriculture, with deficits of water availability for the maintenance of crops destined for human food and animal production. Seasonality of forage quantity and quality is a critical obstacle to support domesticated herds over the year. Elephantgrass (Pennisetum purpureum Schum.) is a tropical forage widely used for feeding ruminants, mainly in the form of cut-and-carry, which has the potential to increase tropical pasture productivity, due to the large amount of roughage produced per unit of area. Research evaluated the response of tall and dwarf elephantgrass genotypes under irrigation considering its potential for complementing ruminant diets. This study showed that irrigation of elephantgrass, particularly during the dry season, may improve the regularity of forage production with good nutritive value.This two-year study evaluated the effect of Pennisetum purpureum genotypes under rainfed or irrigated conditions, during the dry and rainy seasons, on herbage, leaf, and stem dry matter (DM) accumulation rates, nutritive value, and carbohydrate and protein fractionation. Treatments were tall (Iri 381 and Elefante B) or dwarf (Mott and Taiwan A-146 2.37) genotypes under rainfed or irrigated conditions. Taiwan A-146 2.37 (146 kg DM ha per day) showed similar herbage accumulation rate (HAR) to tall genotypes during the rainy season (124 and 150 kg DM/ha per day, respectively). Dwarf genotypes showed differences in leaf accumulation rate (LAR) (66 and 49 kg DM/ha per day). Mott leaf had less neutral detergent fiber (NDF) (589 g/kg DM) than Taiwan A-146 2.37 (598 g/kg DM), and tall genotypes had generally greater NDF (668 g/kg DM) than the dwarf genotypes. Irrigation increased fiber deposition in the leaf. Stems of all genotypes had lower in vitro digestible dry matter (IVDDM) (378 g/kg DM) under rainfed conditions in the rainy season. Leaf from irrigated plots had 23% more carbohydrate C fraction (160 g/kg CHO) than those from rainfed plots (122 g/kg CHO). Dwarf genotypes had generally greater nutritive value than tall genotypes. These genotypes show promise under irrigation to fill forage gaps during dry periods.

Estimación de la evapotranspiración del cultivo de arroz en Perú mediante el algoritmo METRIC e imágenes VANT

Modern remote measurement techniques using cameras mounted on an unmanned aerial vehicle (UAV) have made possible to acquire high-resolution images and estimating evapotranspiration at more detailed spatial and temporal scales. The objective of the present research was to estimate crop evapotranspiration (ETc) of rice crop using the “mapping evapotranspiration with internalized calibration model (METRIC)” using high spatial resolution multispectral and thermal images obtained from a UAV. A total of 18 flights with UAV were performed to get the images; likewise, data were collected from the weather station and thermocouple information installed in the crop canopy under soil water potential conditions of –10 kPa (T1), –15 kPa (T2), –20 kPa (T3) and a control of 0 kPa (T0), from November 13, 2017, to April 30, 2018. The results indicate that the METRIC model compared to ETc measurements recorded by a field drainage lysimeter presents a Pearson correlation coefficient (r) of 0.97, root mean square error (RMSE) of 0.51 mm d<sup>–1</sup>, Nash-Sutcliffe coefficient (EF) of 0.87 and underestimation of 7 %. Evapotranspiration reached values of 7.48 mm d<sup>–1</sup>, with differences between treatments of 0.2 %, 6 % and 8 % concerning to T0 and yield reduction of 9 %, 34 % and 35 % for T1, T2 and T3 soil water potential. The high[1]resolution images allowed obtaining detailed information on the spatial variability of ETc that could be used in the more efficient application of plot irrigation.

Response of lentil cultivars to Sclerotinia white mold and Botrytis grey mold infection under irrigated and dryland conditions

Diseases such as Sclerotinia white mold (SWM), caused by the fungus Sclerotinia sclerotiorum (Lib.) de Bary, and Botrytis grey mold (BGM), caused by the fungus Botrytis cinerea Pers., may be limiting factors for lentil production in wetter areas of Alberta, Canada. Field trials were conducted at the Lethbridge Research and Development Centre from 2013 to 2015 to evaluate the response of lentil cultivars to SWM and BGM and yield impacts. Ten lentil cultivars from five market classes were evaluated under irrigated and dryland plots with two planting densities (120 and 160 plants·m−2). Year and irrigation had the largest effect on disease incidence, with highest SWM incidence occurring under irrigation in 2013, followed by 2014 and 2015. Conversely, BGM incidence under irrigation was highest in 2015 and lowest in 2013, but levels were lower than SWM. Significantly (P < 0.05) lower disease incidences were observed in dryland plots, which also produced higher yield than irrigated plots. Cultivars varied significantly in SWM incidence and yield under irrigated and dryland conditions, perhaps due to variable disease pressure, but there was no consistent trend in cultivar performance. BGM incidence was similar in cultivars, but differed among years. These findings indicate that SWM may be a limiting factor to lentil production in wetter areas, as the 10 cultivars from five market classes tested were all highly susceptible to SWM.

Phenology of high- and low-density wood deciduous species responds differently to water supply in tropical semiarid regions

Although seasonal rainfall is the main factor regulating plant phenology in the dry tropics, some species flush and flower during the dry season. This apparent paradox was investigated in woody species in semiarid Brazil. A total of 500 mm of water was supplied to three 100 m2 plots along 12 weeks from the beginning of the dry season, when the photoperiod was the shortest. Six deciduous high wood density species (HWD; ≥ 0.5 g cm−3) that had flushed and flowered during the rainy season, had low water potentials (<−3.5 MPa) and shed their leaves in the control plots during the dry season, while in the irrigated plots their water potential was higher (−1.0 MPa), leaves were retained longer, and they flushed and/or flowered again. In both irrigated and control areas, four deciduous low wood density species (LWD) behaved similarly: they shed their leaves at the end of the wet season, maintained a relatively high-water potential (>−0.3 MPa) throughout the dry season and flushed and flowered at the end of this season, when the photoperiod was greater than 12 h. We conclude that the phenophases of HWD species are regulated by water availability and those of LWD species by the photoperiod.

Influence of compost and biochar on soil biological properties under turfgrass supplied deficit irrigation

Turfgrass landscapes are commonly maintained using deficit irrigation. Here we follow-up a prior study, which surveyed turfgrass establishment in plots amended with biochar or compost or a mixture of both and unamended control plots. Following establishment, the plots were differentially irrigated at either full (85% ETo replaced) or deficit (50% ETo replaced) levels for four years and sampled for analysis. Relationships between soil chemical parameters and microbial community biomass and profiles based on phospholipid fatty acid analysis and high throughput sequencing of bacterial/archaeal 16S rRNA genes were determined. Compared to the unamended control soils, compost amended soils with or without biochar underwent greater shifts in soil physiochemical and biological properties than those receiving biochar. Although the impact of compost on the microbial community lessened with time, even 5 years after its incorporation, compost amended soils had increased microbial biomass by 127% and 157% in full and deficit irrigated plots compared to unamended plots. Bacterial/archaeal communities compositionally were more divergent in response to deficit irrigation in the unamended soils than in those amended with compost or biochar. Both soil amendments resulted in reduced relative abundances of nitrifying bacteria and archaea. In compost-amended soils many taxa associated with plant growth promotion and carbon cycling increased in relative abundance, whereas no such effect was observed with biochar. Altogether, these results provide mechanistic insights into how organic amendments affect turfgrass systems and their associated soil microbial communities under full and deficit irrigation regimens.

Soybean seed growth dynamics exposed to heat and water stress during the filling period under field conditions

AbstractSoybean production can be affected by heat (HS) and water stress (WS). However, studies on effects of stresses combination under field conditions are still scarce. The objective of this study was to evaluate the impact of HS, WS and their interaction (HS × WS) during seed filling on seed weight, seed growth rate (SGR) and seed filling duration (SFD) of same phenological age pods from different canopy positions. Two soybean genotypes were exposed to four treatments during seed filling: control (irrigated plots at ambient temperature), HS (plots under temperatures &gt;32°C for 6 hr/day during 15 days), WS (plots under 25% of soil water content, during entire seed filling) and HS × WS. Stresses interaction caused similar responses to WS alone, decreasing yield and its components (seed number and weight), as well as seed weight for each canopy position (SWCP), SGR and SFD. Non‐significant effect of irrigated HS and non‐additive effects was observed in HS × WS plots, exhibiting WS a dominant effect over HS. The SWCP strongly correlated with SGR, exhibiting upper position a trend to higher SWCP than lower one. Seed maximum water content and pod weight, positively associated with SWCP, indicated seed metabolic limitations under WS and HS × WS. Our results advance in the understanding of SW determination under abiotic stresses and highlight the importance of identifying pods of same phenological age to establish accurate comparisons between seeds from different canopy positions.

Effects of mixing tree species and water availability on soil organic carbon stocks are depth dependent in a temperate podzol

AbstractMixing tree species is a forest management strategy put forward to increase and stabilize primary productivity. Yet, little is known about soil organic carbon (SOC) storage in mixed species forests, particularly under water shortage. In this study, we used a tree diversity experiment in southwestern France to assess the interactive effects of water availability (via irrigation) and mixing tree species (monocultures of pine (Pinus pinaster) and birch (Betula pendula) versus mixed plots of pine‐birch and pine‐birch‐oak (Quercus robur)) on SOC stocks in the forest floor and across five mineral soil layers (0–5, 5–15, 15–30, 30–60 and 60–90 cm deep). We found that SOC stocks were negatively affected by irrigation in the forest floor due to an increase in decomposition rates. However, SOC stocks were positively influenced by both the mixing of tree species and irrigation in the mineral soil, particularly at the 15–30‐cm soil depth. This is because root niche partitioning in mixed plots and an increase in tree biomass in irrigated plots may have resulted in greater organic matter inputs through rhizodeposition and the incorporation of microbially‐derived compounds. These preliminary results indicate that SOC dynamics and its response to biotic and abiotic factors are strongly dependent on soil depth. Our data further highlight that the positive effect of mixing trees on SOC stocks was higher in irrigated plots, thereby contradicting the idea that tree mixture effects are expected to be greater when environmental conditions are harsher. We conclude that mixing tree species can increase SOC stocks in the short term in temperate forests, even if the exact mechanisms remain to be identified.Highlights Effects of mixing trees and increasing water availability on SOC are depth dependent. Increase in SOC stocks occurred mainly at the mid‐soil depth (15–30 cm). Effects of tree mixture on SOC were greater when soil water availability was high.

Soil oxygen and water dynamics underlying hypoxic conditions in the root-zone of avocado irrigated with treated wastewater in clay soil

Alternative water sources for agriculture are in high demand in a world with diminishing fresh water (FW) availability. Treated wastewater (TWW) offers a reliable alternative, but increasing evidence is pointing to damage to TWW irrigated orchards planted in clay soils related to soil hypoxia. The mechanisms responsible for this hypoxia have not been extensively studied to date. The aim of this study was to elucidate meaningful insights into the mechanisms responsible for the hypoxia in TWW irrigated orchards planted in clay soils using a novel approach whereby parameters describing the soil oxygen and water temporal dynamics are analyzed. To that end, soil oxygen and soil water tension (SWT) measurements from a two year field experiment comparing TWW to FW irrigation in an avocado orchard planted in a clay soil (60 % clay) were used. The deterioration in oxygen levels occurred as the irrigation season progressed, and the oxygen availability decreased with depth (10–35 cm depth). During August-September, when the lowest oxygen concentrations were measured, the water content at which oxygen supply matched oxygen consumption at 35-cm depth did not differ between treatments (∼50 mbar), but the TWW irrigated soil experienced ∼47 % more time at wetter conditions. Lower oxygen decline rates were observed in the TWW irrigated plots which countered the previous concept that TWW leads to increased soil oxygen consumption. The findings point towards the rate of soil drying as the prime cause of differences – TWW irrigated plots dried in a rate which is nearly 4-times smaller than that in FW irrigated plots during the dark and light hours, reflecting slower drainage and water uptake respectively. It is suggested that soil hypoxia induced by the low soil drainage in TWW irrigated clay soils impairs tree water uptake, which further hinders the soil oxygen levels. Based on these results management tools are suggested to allow sustainable irrigation with TWW in the future. Furthermore, the work demonstrates how analysis of parameters describing the oxygen hourly changes can be utilized to gain mechanistic insights unto processes affecting the oxygen regime in the soil.

Translocation factor of heavy metals by elephant grass grown with varying concentrations of landfill leachate.

The aim of this study is to obtain the translocation factor by application of landfill leachate (LL) diluted in public irrigation water (IW). Pennisetum purpureum Schum (elephant grass) was cultivated for 83 days in an experimental water reuse unit. The present work was developed at the Experimental Water Reuse Unit (UERA), on the UFERSA campus in Mossoró, RN, Brazil. Plot irrigation was based on water balance and crop evapotranspiration (ETc). The concentration in the plant tissue (root and leaf) of the following heavy metals was measured to determine the respective translocation factors: manganese (Mn), zinc (Zn), copper (Cu), nickel (Ni), cadmium (Cd), and lead (Pb). The experiment was set up in a randomized block design with five treatments (T1, plots irrigated only with IW; T2, 50% of LL dose plus IW; T3, 100% of LL dose plus IW; T4, 150% of LL dose plus IW; and T5, 200% of LL dose plus IW) and five replications. All treatments received LL plus IW depth of 491.02 mm for 83 days of P. purpureum cultivation. The data obtained were submitted to multivariate analysis plus the nonparametric Kruskal-Wallis test to compare the means. Pennisetum purpureum showed a potential to accumulate metals in its tissues, mainly Mn, Zn, and Cu. The treatments that most favored the extraction of these metals were T2 and T5; in this sense, P. purpureum was not efficient in translocating heavy metals, since the translocation factor observed in all treatments was below 1.0, indicating that the species used extract heavy metals from soil solution and keeps in yours roots. This suggests planting P. purpureum may not be a viable option to remediate environments highly contaminated with heavy metals.

Pembuatan Sistem Informasi Irigasi dan Kebutuhan Air dengan Standard dan Mekanisme Akses berbasis Infrastruktur data Geospasial untuk Irigasi Pertanian di Kabupaten Karanganyar

Manajemen irigasi diperlukan dalam mendukung tatakelola dan penentuan kebutuhan air, khususnya pada lahan pertanian. Manajemen irigasi tersebut dapat dioptimalkan dengan melakukan inventarisasi data irigasi di dalam sebuah web map. Inventarisasi data tersebut bertujuan agar skenario tukar guna data spasial khususnya terkait manajemen irigasi dapat berjalan optimal. Skenario tukar guna data dapat optimal apabila diseminasi informasi yang ada dapat saling terintegrasi. Permasalahan utama yaitu diseminasi informasi ataupun data terkait kebutuhan air untuk lahan pertanian ada pada sumber yang terpisah sehingga sulit untuk menganalisis hasil integrasi dari data tersebut. Permasalahan tersebut dapat diselesaikan dengan menyelaraskan data (curah hujan efektif, evapotranspirasi, porositas, total kehilangan air, efisiensi irigasi, petak irigasi, saluran irigasi dan petak irigasi) sehingga data dapat diintegrasikan dan dapat dimanfaatkan oleh pengguna. Pada tulisan ini dilakukan 5 tahapan kegiatan yaitu perencanaan dan pengumpulan data, analisis, desain sistem, implementasi dan evaluasi. Hasil yang didapat yaitu berupa web map yang digunakan untuk memfasilitasi ketersediaan dan akses data spasial yang di dalamnya terdapat data irigasi dan klimatologi. Dalam web map yang dibangun terdapat fasilitas-fasilitas diantaranya pembacaan data, penambahan data, pembaruan data, penghapusan data dan pengunduhan data. Web map yang dinamakan Sistem Informasi Irigasi dan Kebutuhan Air (SIRISKA) ini merupakan sebuah web map dinamis yang menggunakan fungsi Create Read Update and Delete (CRUD) ke basis data. Web map dibangun berdasarkan integrasi antara komponen back-end yang terdiri atas PostgreSQL (basisdata), PHP (server-side scripting), Apache (web server) dan komponen front end yang terdiri atas JavaScript, HTML dan CSS. Web map SIRISKA dievaluasi dengan beberapa parameter diantaranya efektifitas, kebergunaan, konsistensi, kejelasan arsitektural dan visual, dan kemampuan data sharing. Berdasarkan evaluasi tersebut dapat disimpulkan bahwa sistem informasi yang dibuat dapat memudahkan pengguna untuk melakukan tukar guna data dan mendapatkan informasi kebutuhan air irigasi untuk setiap petak irigasi.