scholarly journals Changes of Streamflow Caused by Early Start of Growing Season in Nevada, United States

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1067
Author(s):  
Hong Fang ◽  
Jianting Zhu ◽  
Muattar Saydi ◽  
Xiaohua Chen
Keyword(s):  
United States ◽  
Soil Moisture ◽  
Growing Season ◽  
The United States ◽  
Insect Infestation ◽  
Aquifer Recharge ◽  
Soil Moisture Deficit ◽  
Moisture Deficit ◽  
Ecological Simulation ◽  
The Relationship

The fluctuation of streamflow in snowmelt-dominated watersheds may be an indicator of climate change. However, the relationship between the start of growing season (SOS) and the streamflow in snowmelt-dominated watersheds is not clear. In this study, we update the Coupled Hydro-Ecological Simulation System (CHESS) model by incorporating the Growing Season Index (GSI) module to estimate the start of the growing season. The updated CHESS model is then used to calculate the streamflow in the Cleve Creek, Incline Creek and Twin River watersheds located in Nevada in the United States from 1981 to 2017. This updated CHESS can be applied in any regions that are suitable for deciduous vegetation. The streamflow in the static and dynamic scheme in the three watersheds have been simulated between 1981 and 2017 with the NS of 0.52 and 0.80 in the Cleve Creek, 0.46 and 0.75 in the Incline Creek, and 0.42 and 0.70 in the Twin River watersheds, respectively. The results illustrate that the SOS have come around 3–5 weeks earlier during the last 37 years. The results illustrate a high correlation between the temperature and the timing of the SOS. Early SOS leads to a substantial increase in total annual transpiration. An increase in annual transpiration can reduce aquifer recharge and increase cumulative growing season soil moisture deficit. Comparing to the streamflow without vegetation, the streamflow with vegetation is smaller due to transpiration. As the SOS comes earlier, the peaks of the streamflow with vegetation also come earlier. If the shifts in SOS continue, the effects on annual rates of transpiration can be significant, which may reduce the risk of flooding during snowmelt. On the other hand, earlier SOS may cause soil moisture to decline during summer, which would increase the drought stress in trees and the risk of wildfires and insect infestation.

scholarly journals EVALUATION OF THE GROWING CONDITIONS OF SEA-BUCKTHORN PLANTATIONS UNDER INUNDATIVE IRRIGATION

2021 ◽  
pp. 30-36
Author(s):  
S.V. Makarychev ◽  
Keyword(s):  
Soil Moisture ◽  
Soil Layer ◽  
Growing Season ◽  
Sea Buckthorn ◽  
Parent Rock ◽  
Illuvial Horizon ◽  
Soil Moisture Deficit ◽  
Moisture Deficit ◽  
Ture Content ◽  
Humus Horizons

Sea-buckthorn grows well on slope lands that are high-ly drained and lack stagnant water. The optimum soil mois-ture content for sea-buckthorn corresponds to 70% of the lowest moisture capacity. Under continuous soil moisture deficit, the leaf surface area decreased, the fruits were poorly set as a result of ovary drop during the first half of the growing season, and berry size decreased. In this re-gard, the study of the water regime of the soil under sea-buckthorn plantations the possibility of its regulation re-mained quite topical. The available moisture in the humus horizons of chernozem in May 2004 corresponded to a satisfactory level. At the end of summer, the moisture con-tent of the chernozem decreased to unsatisfactory state. As a result, the plants experienced water deprivation throughout the growing season. Naturally, the need arose for irrigation, especially in June and August with irrigation rates of 490 and 280 t per m3, respectively. In the underly-ing horizons, the soil moisture deficit was weaker. In the humus horizons, the available moisture in the chernozem in the middle of the slope did not differ much from the mois-ture content at its top. At the same time, in the transitional BC layer in the second half of summer, the available mois-ture content was significantly higher. This difference was also found in the parent rock. In the lower part of theslope, the one-meter soil layer contained a greater amount of moisture which contributed to the decrease of its deficit during the entire growing season. This was especially no-ticeable in the illuvial horizon and parent rock. In the sec-ond half of summer,the available moisture content here remained higher than in the upper slope sites. In conclu-sion, it should be noted that only humus-accumulative hori-zons A (arable) + AB needed irrigation with different irriga-tion rates depending on the location of the sea-buckthorn plantations on the slope and their growth features.

scholarly journals Influence of the Ocean and Greenhouse Gases on Severe Drought Likelihood in the Central United States in 2012

2017 ◽  
Vol 30 (5) ◽  
pp. 1789-1806 ◽  
Author(s):  
David E. Rupp ◽  
Sihan Li ◽  
Philip W. Mote ◽  
Neil Massey ◽  
Sarah N. Sparrow ◽  
...  
Keyword(s):  
United States ◽  
Soil Moisture ◽  
Greenhouse Gases ◽  
Extreme Drought ◽  
Exceedance Probability ◽  
Soil Moisture Deficit ◽  
Anthropogenic Forcing ◽  
Moisture Deficit ◽  
Central United States ◽  
Sst Anomalies

Abstract The impacts of sea surface temperature (SST) anomalies and anthropogenic greenhouse gases on the likelihood of extreme drought occurring in the central United States in the year 2012 were investigated using large-ensemble simulations from a global atmospheric climate model. Two sets of experiments were conducted. In the first, the simulated hydroclimate of 2012 was compared to a baseline period (1986–2014) to investigate the impact of SSTs. In the second, the hydroclimate in a world with 2012-level anthropogenic forcing was compared to five “counterfactual” versions of a 2012 world under preindustrial forcing. SST anomalies in 2012 increased the simulated likelihood of an extreme summer precipitation deficit (e.g., the deficit with a 2% exceedance probability) by a factor of 5. The likelihood of an extreme summer soil moisture deficit increased by a similar amount, due in great part to a large spring soil moisture deficit carrying over into summer. An anthropogenic impact on precipitation was detectable in the simulations, doubling the likelihood of what would have been a rainfall deficit with a 2% exceedance probability under preindustrial-level forcings. Despite this reduction in rainfall, summer soil moisture during extreme drought was essentially unaffected by anthropogenic forcing because of 1) evapotranspiration declining roughly one-to-one with a decrease in precipitation due to severe water supply constraint and despite higher evaporative demand and 2) a decrease in stomatal conductance, and therefore a decrease in potential transpiration, with higher atmospheric CO2 concentrations.

scholarly journals Stolon Growth Characteristics and Establishment Rates of Zoysiagrass Progeny

HortScience ◽  
2011 ◽  
Vol 46 (1) ◽  
pp. 113-117 ◽  
Author(s):  
David O. Okeyo ◽  
Jack D. Fry ◽  
Dale J. Bremer ◽  
Ambika Chandra ◽  
Dennis Genovesi ◽  
...  
Keyword(s):  
United States ◽  
Transition Zone ◽  
Growing Season ◽  
The United States ◽  
Elongation Rate ◽  
Growth Characteristics ◽  
Short Term ◽  
The Relationship

Zoysiagrass (Zoysia spp.) is recognized for its low requirements for pesticide and fertilizer input, but Meyer (Z. japonica Steud.), the cultivar commonly used in the transition zone of the United States, is slow to establish. We evaluated new zoysiagrass progeny for stolon growth characteristics and rate of establishment and determined the relationship between stolon growth characteristics and coverage. ‘Meyer’, DALZ 0102 (a Z. japonica), and 18 progeny from crosses of ‘Emerald’ (Z. japonica × Z. tenuifolia Willd. ex Thiele) or a Z. matrella (L.) Merr. × Z. japonica were planted as 6-cm diameter plugs on 30.5 × 30.5-cm centers in 1.5 × 1.5-m plots in 2007 and as single 10-cm diameter plugs in 1.2 × 1.2-m plots in 2008 in Manhattan, KS. Data were collected weekly on number of stolons initiated per plug, stolon elongation, and number of stolon branches. Two researchers rated coverage visually near the end of each growing season. Rate of stolon initiation ranged from 2.2/week to 8.6/week. Elongation rate ranged from 18.8 to 65.1 mm/week. At 11 weeks after planting in 2007, four of 18 progeny had superior coverage to ‘Meyer’; at 11 weeks after planting in 2008, 13 of 18 progeny had superior coverage to ‘Meyer’. Rate of stolon initiation was positively correlated (P < 0.01) with zoysiagrass coverage (r = 0.66, in 2007; r = 0.94 in 2008); likewise, stolon elongation was positively correlated with coverage in 2007 (r = 0.52, P < 0.01) and 2008 (r = 0.53, P < 0.05). Stolon initiation or elongation could be used in short-term evaluations to predict rate of zoysiagrass coverage from plugs. Greater stolon initiation or elongation of experimental some zoysiagrass progeny makes them promising for alternatives to ‘Meyer’ for overcoming slow establishment rates.

Experiments on irrigation of sugar beet

1952 ◽  
Vol 42 (3) ◽  
pp. 286-292 ◽  
Author(s):  
H. L. Penman
Keyword(s):  
Soil Moisture ◽  
Sugar Beet ◽  
Field Experiments ◽  
Field Capacity ◽  
Growing Season ◽  
Maximum Growth ◽  
Weather Data ◽  
Soil Moisture Deficit ◽  
Basic Principles ◽  
Moisture Deficit

It is assumed that maximum growth requires maximum transpiration, and that maximum transpiration can be maintained by keeping the soil near to field capacity throughout the growing season. Transpiration rates can be calculated from weather data (the basic principles are outlined and an example of the calculation given), and the paper describes four field experiments in which attempts were made to control the water content of the soil throughout the growing season, by irrigation from overhead spray-lines.In spite of differences in season and soil, the four sets of data are consistent in showing that maximum sugar yield is obtained when the soil-moisture deficit (amount of rain or irrigation needed restore the soil to field capacity) does not exceed about 2 in. in mid-July, or about 4 in. in mid-September.

Abusive Men's Use of Children to Control Their Partners and Ex-Partners

2007 ◽  
Vol 12 (1) ◽  
pp. 54-61 ◽  
Author(s):  
Marisa L. Beeble ◽  
Deborah Bybee ◽  
Cris M. Sullivan
Keyword(s):  
United States ◽  
Intimate Partner Violence ◽  
Partner Violence ◽  
Emotional Abuse ◽  
The United States ◽  
Intimate Partner ◽  
Anecdotal Evidence ◽  
Multiple Variables ◽  
The Relationship

While research has found that millions of children in the United States are exposed to their mothers being battered, and that many are themselves abused as well, little is known about the ways in which children are used by abusers to manipulate or harm their mothers. Anecdotal evidence suggests that perpetrators use children in a variety of ways to control and harm women; however, no studies to date have empirically examined the extent of this occurring. Therefore, the current study examined the extent to which survivors of abuse experienced this, as well as the conditions under which it occurred. Interviews were conducted with 156 women who had experienced recent intimate partner violence. Each of these women had at least one child between the ages of 5 and 12. Most women (88%) reported that their assailants had used their children against them in varying ways. Multiple variables were found to be related to this occurring, including the relationship between the assailant and the children, the extent of physical and emotional abuse used by the abuser against the woman, and the assailant's court-ordered visitation status. Findings point toward the complex situational conditions by which assailants use the children of their partners or ex-partners to continue the abuse, and the need for a great deal more research in this area.

The United States and the Iranian Nuclear Programme

2018 ◽  
Author(s):  
Steven Hurst
Keyword(s):  
United States ◽  
Decision Making ◽  
Domestic Politics ◽  
The United States ◽  
Nixon Administration ◽  
Comprehensive Plan ◽  
The Us ◽  
Nuclear Issue ◽  
The Relationship

The United States, Iran and the Bomb provides the first comprehensive analysis of the US-Iranian nuclear relationship from its origins through to the signing of the Joint Comprehensive Plan of Action (JCPOA) in 2015. Starting with the Nixon administration in the 1970s, it analyses the policies of successive US administrations toward the Iranian nuclear programme. Emphasizing the centrality of domestic politics to decision-making on both sides, it offers both an explanation of the evolution of the relationship and a critique of successive US administrations' efforts to halt the Iranian nuclear programme, with neither coercive measures nor inducements effectively applied. The book further argues that factional politics inside Iran played a crucial role in Iranian nuclear decision-making and that American policy tended to reinforce the position of Iranian hardliners and undermine that of those who were prepared to compromise on the nuclear issue. In the final chapter it demonstrates how President Obama's alterations to American strategy, accompanied by shifts in Iranian domestic politics, finally brought about the signing of the JCPOA in 2015.

Violence, Social Movements, and Black Freedom Struggles

Contention ◽  
2021 ◽  
pp. 1-9
Author(s):  
AK Thompson
Keyword(s):  
United States ◽  
Social Movements ◽  
The United States ◽  
United States Today ◽  
Black Freedom ◽  
Current Events ◽  
Research Agendas ◽  
Ambivalent Relationship ◽  
The Relationship ◽  
Freedom Struggles

George Floyd’s murder by police on 26 May 2020 set off a cycle of struggle that was notable for its size, intensity, and rate of diffusion. Starting in Minneapolis, the uprising quickly spread to dozens of other major cities and brought with it a repertoire that included riots, arson, and looting. In many places, these tactics coexisted with more familiar actions like public assemblies and mass marches; however, the inflection these tactics gave to the cycle of contention is not easily reconciled with the protest repertoire most frequently mobilized during movement campaigns in the United States today. This discrepancy has led to extensive commentary by scholars and movement participants, who have often weighed in by considering the moral and strategic efficacy of the chosen tactics. Such considerations should not be discounted. Nevertheless, I argue that both the dynamics of contention witnessed during the uprising and their ambivalent relationship to the established protest repertoire must first be understood in historical terms. By considering the relationship between violence, social movements, and Black freedom struggles in this way, I argue that scholars can develop a better understanding of current events while anticipating how the dynamics of contention are likely to develop going forward. Being attentive to these dynamics should in turn inform our research agendas, and it is with this aim in mind that I offer the following ten theses.

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