EVALUATION OF REVEGETATION TECHNIQUES FOR ROADSIDE CONSTRUCTION SITES

Vegetation is often used to control erosion on right-of-way construction sites, but disturbed conditions provide challenges. This research evaluated the impact of common techniques for preparing seedbeds. The study assessed the use of topsoil, and the use of a hydraulic erosion-control product was compared to straw. Experimental seed mixtures were evaluated to understand how native and non-native seeds performed. The intent was to identify critical practices to use in general seeding and mulching specifications. A plot study was conducted comparing vegetation established during one growing season. Treatments included combinations of seed mixture, topsoil treatment, and mulch types. Three seed mixtures were considered: (1) currently used mixture, (2) a warm-season experimental mixture, and (3) a cool-season experimental mixture. Plots with topsoil and no topsoil were compared, and both straw and hydraulic erosion control products were considered. Ground cover, compaction, and biomass were evaluated. Results suggest that alternative seed mixtures that include native and low-threat-level species can provide adequate cover to meet permitting requirements in the first growing season. The warm-season seed mixture provided less cover than the other two mixtures after eight days, but no differences were determined in ground cover among the three seed mixtures at the end of the growing season. Initial germination was improved with hydraulic mulch, but long-term cover was equivalent between hydraulic and straw mulch. Topsoil application would not be recommended if the soil contains undesirable species, and the use of organic amendment products may be more desirable than topsoil alone; however, specifications need to allow the use of these products.

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Control of Grass and Sedge in Allegheny Hardwood Stands with Roundup-Residual Herbicide Tank Mixes

Northern Journal of Applied Forestry ◽

10.1093/njaf/7.3.124 ◽

1990 ◽

Vol 7 (3) ◽

pp. 124-129 ◽

Cited By ~ 4

Author(s):

Stephen B. Horsley

Keyword(s):

Ground Cover ◽

Growing Season ◽

Soil Disturbance ◽

Response Data ◽

Small Plot ◽

Application Date ◽

Forest Floor Disturbance ◽

Logging Disturbance ◽

Residual Herbicide ◽

The Impact

Abstract A small plot experiment was carried out to investigate the effect of forest floor disturbance on establishment of grasses and sedges and to test whether addition of a residual herbicide in tank mix with Roundup could reduce grass and sedge reinvasion. Seven residual herbicides, each at three rates of application, were tested against a Roundup control. Herbicides were Hyvar X (bromacil), Karmex (diuron), Racer (fluorochloridone) (R-40244)), Devrinol (napropamide), Surflan (oryzalin), Oust (sulfometuron methyl), and Sinbar (terbacil). Herbicides were applied on three dates of application at two northwestern Pennsylvania sites. Half of each plot was mechanically disturbed to simulate logging disturbance. Response data were collected for 2 or 3 years after treatment application. Soil disturbance was a significant factor in promoting emergence of grass and sedge; most germination occurred during the growing season immediately following treatment. Little grass or sedge emerged on undisturbed areas. In the second growing season following treatment, plants that did emerge grew to full size. Two of the tank mixes, Roundup plus Hyvar X and Roundup plus Karmex, gave less control of vegetation on the plot at the time of treatment than Roundup alone. Most Round-up-residual herbicide tank mixes reduced emergence and growth of new grass and sedge plants, regardless of application date; however, the amount and duration of control differed among herbicides. Roundup (1 # ai/ac) plus Surflan (2-4 # ai/ac) and Roundup plus Oust (0.09-0.19 # ai/ac) produced the best results reducing grass and sedge ground cover for at least 3 and 2 years, respectively. By use of Roundup-residual herbicide tank mixes and manipulation of cutting techniques, forest land managers can minimize the impact of grass and sedge on the forest regeneration process in Allegheny hardwood stands. North. J. Appl. For. 7:124-129, September 1990.

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Turfgrass Monoculture, Cool-Cool, and Cool-Warm Season Seed Mixture Establishment and Growth Responses

HortScience ◽

10.21273/hortsci.39.7.1732 ◽

2004 ◽

Vol 39 (7) ◽

pp. 1732-1735 ◽

Cited By ~ 6

Author(s):

Hassan Salehi ◽

Morteza Khosh-Khui

Keyword(s):

Root Growth ◽

Chlorophyll Content ◽

Warm Season ◽

Dry Weight ◽

Kentucky Bluegrass ◽

Rooting Depth ◽

Growth Responses ◽

Seed Mixture ◽

Tiller Density ◽

Seed Mixtures

Turfgrass seeds can be sown individually, in mixes, or overseeded to provide green color and uniform surfaces in all the seasons. This investigation was conducted to compare different turfgrass species and their seed mixtures. In this research, the turfgrasses—perennial ryegrass (Lolium perenne L. `Barball'), kentucky bluegrass (Poa pratensis L. `Merion'), common bermudagrass (Cynodon dactylon [L.] Pers.), and strong creeping red fescue (Festuca rubra L. var. rubra `Shadow')—in monoculture or in mixtures of 1:1 (by weight) and a 1:1:1:1 (by weight) and two sport turfgrasses—BAR 11 (Barenbrug Co.) and MM (Mommersteeg Co.)—were used. The seeds were sown in March and October (spring and fall sowing) in 1998 and 1999. The experiments were conducted in a split-split block design with year as main plot, sowing season as subplot, and turfgrass types as subsubplot. The turfgrasses were compared by measuring visual quality, chlorophyll index after winter and summer, rooting depth, verdure and/or root fresh and dry weight, tiller density, and clippings fresh and dry weight. Fall sowing was superior to spring sowing and resulted in greater root growth, clipping yield, and chlorophyll content. Poa+Cynodon seed mixture was the best treatment and had high tiller density, root growth, and chlorophyll content. Lolium and Festuca monocultures, and Poa+Festuca and Cynodon+Festuca seed mixtures were not suitable with regard to low tiller density, sensitivity to high temperatures, low root growth, and low tiller density, respectively. The cool-warm-season seed mixture (Poa+Cynodon) can be used alternatively in overseeding programs in the areas with soil and environmental conditions similar to this research site.

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A Predictive Model of the Impact of the Skidding System on Forest Soil in Severe Climatic Conditions

Lesnoy Zhurnal (Forestry Journal) ◽

10.37482/0536-1036-2020-5-131-144 ◽

2020 ◽

pp. 131-144

Author(s):

S.E. Rudov ◽

◽

V.Ya. Shapiro ◽

O.I. Grigoreva ◽

I.V. Grigorev ◽

...

Keyword(s):

Forest Soil ◽

Warm Season ◽

Climatic Conditions ◽

Soil Freezing ◽

Class Iii ◽

Freezing And Thawing ◽

Metal Structures ◽

Rapid Adjustment ◽

Soil Freezing And Thawing ◽

The Impact

In the Russian Federation logging operations are traditionally carried out in winter. This is due to the predominance of areas with swamped and water-logged (class III and IV) soils in the forest fund, where work of forestry equipment is difficult, and sometimes impossible in the warm season. The work of logging companies in the forests of the cryolithozone, characterized by a sharply continental climate, with severe frosts in winter, is hampered by the fact that forest machines are not recommended to operate at temperatures below –40 °C due to the high probability of breaking of metal structures and hydraulic system. At the same time, in the warm season, most of the cutting areas on cryosolic soils become difficult to pass for heavy forest machines. It turns out that the convenient period for logging in the forests of the cryolithozone is quite small. This results in the need of work in the so-called off-season period, when the air temperature becomes positive, and the thawing processes of the soil top layer begin. The same applies to the logging companies not operating in the conditions of cryosolic soils, for instance, in the Leningrad, Novgorod, Pskov, Vologda regions, etc. The observed climate warming has led to a significant reduction in the sustained period of winter logging. Frequent temperature transitions around 0 °C in winter, autumn and spring necessitate to work during the off-season too, while cutting areas thaw. In bad seasonal and climatic conditions, which primarily include off-season periods in general and permafrost in particular, it is very difficult to take into account in mathematical models features of soil freezing and thawing and their effect on the destruction nature. The article shows that the development of long-term predictive models of indicators of cyclic interaction between the skidding system and forest soil in adverse climatic conditions of off-season logging operations in order to improve their reliability requires rapid adjustment of the calculated parameters based on the actual experimental data at a given step of the cycles.

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Ecosystem modeling of methane and carbon dioxide fluxes for boreal forest sites

Canadian Journal of Forest Research ◽

10.1139/x00-164 ◽

2001 ◽

Vol 31 (2) ◽

pp. 208-223 ◽

Cited By ~ 11

Author(s):

Christopher Potter ◽

Jill Bubier ◽

Patrick Crill ◽

Peter Lafleur

Keyword(s):

Carbon Dioxide ◽

Boreal Forest ◽

Land Surface ◽

Net Primary Production ◽

Ground Cover ◽

Methane Flux ◽

Growing Season ◽

Ecosystem Model ◽

Heat Fluxes ◽

Water Levels

Predicted daily fluxes from an ecosystem model for water, carbon dioxide, and methane were compared with 1994 and 1996 Boreal EcosystemAtmosphere Study (BOREAS) field measurements at sites dominated by old black spruce (Picea mariana (Mill.) BSP) (OBS) and boreal fen vegetation near Thompson, Man. Model settings for simulating daily changes in water table depth (WTD) for both sites were designed to match observed water levels, including predictions for two microtopographic positions (hollow and hummock) within the fen study area. Water run-on to the soil profile from neighboring microtopographic units was calibrated on the basis of daily snowmelt and rainfall inputs to reproduce BOREAS site measurements for timing and magnitude of maximum daily WTD for the growing season. Model predictions for daily evapotranspiration rates closely track measured fluxes for stand water loss in patterns consistent with strong controls over latent heat fluxes by soil temperature during nongrowing season months and by variability in relative humidity and air temperature during the growing season. Predicted annual net primary production (NPP) for the OBS site was 158 g C·m2 during 1994 and 135 g C·m2 during 1996, with contributions of 75% from overstory canopy production and 25% from ground cover production. Annual NPP for the wetter fen site was 250 g C·m2 during 1994 and 270 g C·m2 during 1996. Predicted seasonal patterns for soil CO2 fluxes and net ecosystem production of carbon both match daily average estimates at the two sites. Model results for methane flux, which also closely match average measured flux levels of 0.5 mg CH4·m2·day1 for OBS and 2.8 mg CH4·m2·day1 for fen sites, suggest that spruce areas are net annual sinks of about 0.12 g CH4·m2, whereas fen areas generate net annual emissions on the order of 0.30.85 g CH4·m2, depending mainly on seasonal WTD and microtopographic position. Fen hollow areas are predicted to emit almost three times more methane during a given year than fen hummock areas. The validated model is structured for extrapolation to regional simulations of interannual trace gas fluxes over the entire North America boreal forest, with integration of satellite data to characterize properties of the land surface.

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115 Nitrogen fertilizer effects on above ground sward characteristics and beef heifer performance from native warm-season grass blends

Journal of Animal Science ◽

10.1093/jas/skz397.060 ◽

2020 ◽

Vol 98 (Supplement_2) ◽

pp. 26-27

Author(s):

Caroline Chappell ◽

Landon Marks ◽

Katie Mason ◽

Mary K Mullenix ◽

Sandra L Dillard ◽

...

Keyword(s):

Nutritive Value ◽

Warm Season ◽

Ground Cover ◽

Application Rate ◽

Light Interception ◽

Botanical Composition ◽

Forage Production ◽

Beef Heifers ◽

Fertilizer Application Rate ◽

Canopy Light Interception

Abstract A 2-yr study was conducted at Black Belt Research and Extension Center in Marion Junction, AL, to evaluate the effect of nitrogen (N) fertilizer application rate on forage production characteristics, nutritive value, and animal performance of beef heifers grazing a mixture of native warm-season grasses (NWSG) including big bluestem, little bluestem, and indiangrass. Six, two-hectare plots were randomly assigned to one of two treatments (0 or 67 kg N ha-1 applied in early April; n = 3 replications per treatment). Paddocks were continuously stocked with four weaned Angus × Simmental beef heifers (initial BW 288 ± 7 kg) from late May/early June through mid-to-late August during 2018 (73 grazing d) and 2019 (70 grazing d), respectively. Put-and-take cattle were used to manage forage to a target of 38 cm. Forage mass and canopy heights were collected every two weeks during the trial. Visual ground cover ratings, canopy light interception, and botanical composition were measured at the beginning and end of the trial in each year. Hand-plucked samples were collected every two weeks during the grazing trial to determine forage nutritional value. Data were analyzed using the PROC MIXED procedure in SAS 9.4, and differences were declared significant when P ≤ 0.05. Nitrogen fertilized NWSG had greater crude protein (P < 0.0001), sward heights (P = 0.0003), and canopy light interception at the beginning of the season (P = 0.0049) compared to non-fertilized paddocks. However, there were no differences (P ≥ 0.05) among N-fertility treatments for mean forage mass, heifer ADG, or BCS across the 2-yr study. Botanical composition data indicated that indiangrass decreased from 64% to 61% (P = 0.0022) and weed pressure increased from 11% to 15% (P = 0.0064) across the summer grazing season. Canopy light interception decreased by 51% from early June to August in fertilized NWSG and 26% in unfertilized paddocks, respectively. These data illustrate that NWSG systems may provide a viable grazing system in the summer months under reduced N inputs.

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Analysing the Impact of Climate Change on Hydrological Ecosystem Services in Laguna del Sauce (Uruguay) Using the SWAT Model and Remote Sensing Data

Remote Sensing ◽

10.3390/rs13102014 ◽

2021 ◽

Vol 13 (10) ◽

pp. 2014

Author(s):

Celina Aznarez ◽

Patricia Jimeno-Sáez ◽

Adrián López-Ballesteros ◽

Juan Pablo Pacheco ◽

Javier Senent-Aparicio

Keyword(s):

Climate Change ◽

Remote Sensing ◽

Ecosystem Services ◽

Water Resources ◽

Swat Model ◽

Remote Sensing Data ◽

Erosion Control ◽

Sensing Data ◽

Extreme Precipitation Events ◽

The Impact

Assessing how climate change will affect hydrological ecosystem services (HES) provision is necessary for long-term planning and requires local comprehensive climate information. In this study, we used SWAT to evaluate the impacts on four HES, natural hazard protection, erosion control regulation and water supply and flow regulation for the Laguna del Sauce catchment in Uruguay. We used downscaled CMIP-5 global climate models for Representative Concentration Pathways (RCP) 2.6, 4.5 and 8.5 projections. We calibrated and validated our SWAT model for the periods 2005–2009 and 2010–2013 based on remote sensed ET data. Monthly NSE and R2 values for calibration and validation were 0.74, 0.64 and 0.79, 0.84, respectively. Our results suggest that climate change will likely negatively affect the water resources of the Laguna del Sauce catchment, especially in the RCP 8.5 scenario. In all RCP scenarios, the catchment is likely to experience a wetting trend, higher temperatures, seasonality shifts and an increase in extreme precipitation events, particularly in frequency and magnitude. This will likely affect water quality provision through runoff and sediment yield inputs, reducing the erosion control HES and likely aggravating eutrophication. Although the amount of water will increase, changes to the hydrological cycle might jeopardize the stability of freshwater supplies and HES on which many people in the south-eastern region of Uruguay depend. Despite streamflow monitoring capacities need to be enhanced to reduce the uncertainty of model results, our findings provide valuable insights for water resources planning in the study area. Hence, water management and monitoring capacities need to be enhanced to reduce the potential negative climate change impacts on HES. The methodological approach presented here, based on satellite ET data can be replicated and adapted to any other place in the world since we employed open-access software and remote sensing data for all the phases of hydrological modelling and HES provision assessment.

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The Impact of Climate Change on the Sugar Content of Grapes and the Sustainability of their Production in the Czech Republic

Sustainability ◽

10.3390/su13010222 ◽

2020 ◽

Vol 13 (1) ◽

pp. 222

Author(s):

Miroslava Navrátilová ◽

Markéta Beranová ◽

Lucie Severová ◽

Karel Šrédl ◽

Roman Svoboda ◽

...

Keyword(s):

Climate Change ◽

Czech Republic ◽

Sugar Content ◽

Growing Season ◽

Vegetation Period ◽

The Czech Republic ◽

Impact Of Climate Change ◽

Secondary Sources ◽

The Impact ◽

Growing Region

The aim of the presented article is to evaluate the impact of climate change on the sugar content of grapes in the Czech Republic during the period 2000–2019 through selected indicators on the basis of available secondary sources. Attention is focused on the developments in both the main wine-growing regions of Moravia and Bohemia. In the field of viticulture and wine-growing, the sugar content of grapes, as a basic parameter for the classification of wines, plays an important role. In the Czech Republic, the average sugar content of grapes has had a constantly growing trend. This trend is evident both in the wine-growing region of Bohemia and in the wine-growing region of Moravia. The impact of climate change, especially the gradual increase of average temperatures in the growing season, cannot be overlooked. It greatly affects, among other things, the sugar content of grapes. Calculations according to the Huglin Index and the Winkler Index were used to determine the relationship between climate and sugar content. These indexes summarize the course of temperatures during the entire vegetation period into a single numerical value. The results show that both indexes describe the effect of air temperature on sugar content in both wine regions of the Czech Republic in a statistically significant way. The Huglin Index shows a higher correlation rate. The Winkler Index proved to be less suitable for both areas. Alternatively, the Winkler Index calculated for a shorter growing season was tested, which showed a higher degree of correlation with sugar content, approaching the significance of the Huglin Index.

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Facilitation Effects of Haloxylon salicornicum Shrubs on Associated Understory Annuals, and a Modified “Stress-Gradient” Hypothesis for Droughty Times

Plants ◽

10.3390/plants9121726 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1726

Author(s):

Nasr H. Gomaa ◽

Ahmad K. Hegazy ◽

Arafat Abdel Hamed Abdel Latef

Keyword(s):

Species Richness ◽

Water Availability ◽

Stress Gradient ◽

Growing Season ◽

Annual Species ◽

Negative Effects ◽

Growing Seasons ◽

Dry Seasons ◽

The Impact ◽

Haloxylon Salicornicum

Perennial shrub-annual plant interactions play key roles in desert regions influencing the structure and dynamics of plant communities there. In the present study, carried out in northwestern Saudi Arabia, we examined the effect of Haloxylon salicornicum shrubs on their associated understory annual species across four consecutive growing seasons, along with a record of the seasonal rainfall patterns. We measured density and species richness of all the annual species in permanent quadrats located beneath individual shrubs, as well as in the spaces between shrubs. During wet growing season H. salicornicum shrubs significantly enhanced the density and species richness of sub-canopy species, whereas in the relatively dry seasons they exerted negative effects on the associated species. In all growing seasons, the presence of shrubs was associated with enhanced soil properties, including increased organic carbon content, silt + clay, and levels of nutrients (N, P and K). Shrubs improved soil moisture content beneath their canopies in the wet growing season, while in the dry seasons they had negative effects on water availability. Differences in effects of H. salicornicum on understory plants between growing seasons seem due to the temporal changes in the impact of shrubs on water availability. Our results suggest the facilitative effects of shrubs on sub-canopy annuals in arid ecosystems may switch to negative effects with increasing drought stress. We discuss the study in light of recent refinements of the well-known “stress-gradient hypothesis”.

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Seasonal and temperature effects on mycorrhizal activity and dependence of cool- and warm-season tallgrass prairie grasses

Canadian Journal of Botany ◽

10.1139/b92-201 ◽

1992 ◽

Vol 70 (8) ◽

pp. 1596-1602 ◽

Cited By ~ 46

Author(s):

S. P. Bentivenga ◽

B. A. D. Hetrick

Keyword(s):

Tallgrass Prairie ◽

Mycorrhizal Fungi ◽

Warm Season ◽

Growing Season ◽

Cool Temperature ◽

Cool Season ◽

Fungal Activity ◽

Prairie Grasses ◽

Vesicular Arbuscular ◽

Warm Season Grasses

Previous research on North American tallgrass prairie grasses has shown that warm-season grasses rely heavily on vesicular–arbuscular mycorrhizal symbiosis, while cool-season grasses are less dependent on the symbiosis (i.e., receive less benefit). This led to the hypothesis that cool-season grasses are less dependent on the symbiosis, because the growth of these plants occurs when mycorrhizal fungi are inactive. Field studies were performed to assess the effect of phenology of cool- and warm-season grasses on mycorrhizal fungal activity and fungal species composition. Mycorrhizal fungal activity in field samples was assessed using the vital stain nitro blue tetrazolium in addition to traditional staining techniques. Mycorrhizal activity was greater in cool-season grasses than in warm-season grasses early (April and May) and late (December) in the growing season, while mycorrhizal activity in roots of the warm-season grasses was greater (compared with cool-season grasses) in midseason (July and August). Active mycorrhizal colonization was relatively high in both groups of grasses late in the growing season, suggesting that mycorrhizal fungi may proliferate internally or may be parasitic at this time. Total Glomales sporulation was generally greater in the rhizosphere of cool-season grasses in June and in the rhizosphere of the warm-season grasses in October. A growth chamber experiment was conducted to examine the effect of temperature on mycorrhizal dependence of cool- and warm-season grasses. For both groups of grasses, mycorrhizal dependence was greatest at the temperature that favored growth of the host. The results suggest that mycorrhizal fungi are active in roots when cool-season grasses are growing and that cool-season grasses may receive benefit from the symbiosis under relatively cool temperature regimes. Key words: cool-season grasses, tallgrass prairie, vesicular–arbuscular mycorrhizae, warm-season grasses.

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Modeling the Impact of Climate Changes on Crop Yield: Irrigated vs. Non-Irrigated Zones in Mississippi

Remote Sensing ◽

10.3390/rs13122249 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2249

Author(s):

Sadia Alam Shammi ◽

Qingmin Meng

Keyword(s):

Climate Change ◽

Crop Yield ◽

Crop Yields ◽

Negative Impact ◽

Positive Impact ◽

Information Criterion ◽

Growing Season ◽

Maximum Temperature ◽

Linear Regression Models ◽

The Impact

Climate change and its impact on agriculture are challenging issues regarding food production and food security. Many researchers have been trying to show the direct and indirect impacts of climate change on agriculture using different methods. In this study, we used linear regression models to assess the impact of climate on crop yield spatially and temporally by managing irrigated and non-irrigated crop fields. The climate data used in this study are Tmax (maximum temperature), Tmean (mean temperature), Tmin (minimum temperature), precipitation, and soybean annual yields, at county scale for Mississippi, USA, from 1980 to 2019. We fit a series of linear models that were evaluated based on statistical measurements of adjusted R-square, Akaike Information Criterion (AIC), and Bayesian Information Criterion (BIC). According to the statistical model evaluation, the 1980–1992 model Y[Tmax,Tmin,Precipitation]92i (BIC = 120.2) for irrigated zones and the 1993–2002 model Y[Tmax,Tmean,Precipitation]02ni (BIC = 1128.9) for non-irrigated zones showed the best fit for the 10-year period of climatic impacts on crop yields. These models showed about 2 to 7% significant negative impact of Tmax increase on the crop yield for irrigated and non-irrigated regions. Besides, the models for different agricultural districts also explained the changes of Tmax, Tmean, Tmin, and precipitation in the irrigated (adjusted R-square: 13–28%) and non-irrigated zones (adjusted R-square: 8–73%). About 2–10% negative impact of Tmax was estimated across different agricultural districts, whereas about −2 to +17% impacts of precipitation were observed for different districts. The modeling of 40-year periods of the whole state of Mississippi estimated a negative impact of Tmax (about 2.7 to 8.34%) but a positive impact of Tmean (+8.9%) on crop yield during the crop growing season, for both irrigated and non-irrigated regions. Overall, we assessed that crop yields were negatively affected (about 2–8%) by the increase of Tmax during the growing season, for both irrigated and non-irrigated zones. Both positive and negative impacts on crop yields were observed for the increases of Tmean, Tmin, and precipitation, respectively, for irrigated and non-irrigated zones. This study showed the pattern and extent of Tmax, Tmean, Tmin, and precipitation and their impacts on soybean yield at local and regional scales. The methods and the models proposed in this study could be helpful to quantify the climate change impacts on crop yields by considering irrigation conditions for different regions and periods.

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