The crop yields achieved through traditional plant breeding techniques appear to be nearing a plateau.Therefore,it is essential to accelerate advancements in photosynthesis,the fundamental process by which plants conv...The crop yields achieved through traditional plant breeding techniques appear to be nearing a plateau.Therefore,it is essential to accelerate advancements in photosynthesis,the fundamental process by which plants convert light energy into chemical energy,to further enhance crop yields.Research focused on improving photosynthesis holds significant promise for increasing sustainable agricultural productivity and addressing challenges related to global food security.This review examines the latest advancements and strategies aimed at boosting crop yields by enhancing photosynthetic efficiency.There has been a linear increase in yield over the years in historically released germplasm selected through traditional breeding methods,and this increase is accompanied by improved photosynthesis.We explore various aspects of the light reactions designed to enhance crop yield,including light harvest efficiency through smart canopy systems,expanding the absorbed light spectrum to include far-red light,optimizing non-photochemical quenching,and accelerating electron transport flux.At the same time,we investigate carbon reactions that can enhance crop yield,such as manipulating Rubisco activity,improving the Calvin-Benson-Bassham cycle,introducing CO_(2)concentrating mechanisms in C_(3)plants,and optimizing carbon allocation.These strategies could significantly impact crop yield enhancement and help bridge the yield gap.展开更多
1.The key to achieving China’s dual carbon goals As pointed out in the CO_(2) Emissions in 2023 report released by the International Energy Agency,global carbon dioxide(CO_(2))emis-sions reached 37.4 billion tonnes i...1.The key to achieving China’s dual carbon goals As pointed out in the CO_(2) Emissions in 2023 report released by the International Energy Agency,global carbon dioxide(CO_(2))emis-sions reached 37.4 billion tonnes in 2023[1],setting a new record high.The increase in CO_(2) emissions has exacerbated global warm-ing and led to a series of global climate problems.China is a major emitter of CO_(2).展开更多
The Tarim River Basin(TRB)is a vast area with plenty of light and heat and is an important base for grain and cotton production in Northwest China.In the context of climate change,however,the increased frequency of ex...The Tarim River Basin(TRB)is a vast area with plenty of light and heat and is an important base for grain and cotton production in Northwest China.In the context of climate change,however,the increased frequency of extreme weather and climate events is having numerous negative impacts on the region's agricultural production.To better understand how unfavorable climatic conditions affect crop production,we explored the relationship of extreme weather and climate events with crop yields and phenology.In this research,ten indicators of extreme weather and climate events(consecutive dry days(CDD),min Tmax(TXn),max Tmin(TNx),tropical nights(TR),warm days(Tx90p),warm nights(Tn90p),summer days(SU),frost days(FD),very wet days(R95p),and windy days(WD))were selected to analyze the impact of spatial and temporal variations on the yields of major crops(wheat,maize,and cotton)in the TRB from 1990 to 2020.The three key findings of this research were as follows:extreme temperatures in southwestern TRB showed an increasing trend,with higher extreme temperatures at night,while the occurrence of extreme weather and climate events in northeastern TRB was relatively low.The number of FD was on the rise,while WD also increased in recent years.Crop yields were higher in the northeast compared with the southwest,and wheat,maize,and cotton yields generally showed an increasing trend despite an earlier decline.The correlation of extreme weather and climate events on crop yields can be categorized as extreme nighttime temperature indices(TNx,Tn90p,TR,and FD),extreme daytime temperature indices(TXn,Tx90p,and SU),extreme precipitation indices(CDD and R95p),and extreme wind(WD).By using Random Forest(RF)approach to determine the effects of different extreme weather and climate events on the yields of different crops,we found that the importance of extreme precipitation indices(CDD and R95p)to crop yield decreased significantly over time.As well,we found that the importance of the extreme nighttime temperature(TR and TNx)for the yields of the three crops increased during 2005-2020 compared with 1990-2005.The impact of extreme temperature events on wheat,maize,and cotton yields in the TRB is becoming increasingly significant,and this finding can inform policy decisions and agronomic innovations to better cope with current and future climate warming.展开更多
[Objective] Long-term (over 18 years) fertilization experiments were con- ducted to study the responses of crop yields and soil fertility to long-term nutrient lacking at Zhengzhou in China. [Method] The present stu...[Objective] Long-term (over 18 years) fertilization experiments were con- ducted to study the responses of crop yields and soil fertility to long-term nutrient lacking at Zhengzhou in China. [Method] The present study consisted of five treat- ments: 1 CK (no fertilizer or manure), (2) NP (nitrogen and phosphorus fertilizer applied), 31 NK (nitrogen and potassium fertilizer applied), 4 PK (phosphorus and potassium fertilizer applied) and :5 NPK (nitrogen, phosphorus and potassium fertil- izer applied). [Result] Lacking of nitrogen or phosphorus led to a low yield; however, there was no significant difference in grain yields between the NP and NPK treat- ments which maintained a higher yield. Receiving no phosphorus, soil available phosphorus content declined to about 2.5 mg/kg. The concentration of soil ex- changeable potassium remained constant at a level of 60 mg/kg under the treat- ments without potassium fertilizer addition. Soil potassium spontaneous supply ca- pacity fluctuated around 100%.[Conclusion] In fluvo-aquic soil, nitrogen and phos- phorus were two key limiting factors to grain yields, biomass and yield component factors of wheat and maize, while potassium was not. However, potassium defi- ciency may occur in the future if there was still no potassium fertilizer applied.展开更多
The study attempts to estimate and predict climate impact on crop yields using future temperature projections under two climate emissions scenarios of RCP 4.5 and 8.5 for three different time periods(2030s,2050s and 2...The study attempts to estimate and predict climate impact on crop yields using future temperature projections under two climate emissions scenarios of RCP 4.5 and 8.5 for three different time periods(2030s,2050s and 2080s)across Agro-climatic zones(ACZ)of India.During the period 1966-2011,a significant rise was observed in both the annual mean maximum and minimum temperature across ACZs.Rainfall recorded an annual decline in Himalayan Regions and Gangetic Plains and a rise in Coastal Regions,Plateau&Hills and Western Dry Region.Our results showed high heterogeneity in climate impact on kharif and rabi crop yields(with both negative and positive estimates)across ACZs.It was found that rainfall had a positive effect on most of crop yields,but was not sufficient enough to counterbalance the impact of temperature.Changes in crop yield were more pronounced for higher emission scenario of RCP 8.5.Thus,it was evident that the relative impacts of climate change and the associated vulnerability vary by ACZs,hence comprehensive crop and region-specific adaptation measures should be emphasized that helps in enhancing resilience of agricultural system in short to medium term.展开更多
Compost amendments have remarkable potential for improving soil structure, porosity and water holding capacity. Soil health is the ability to function as a living system, to sustain plant and animal productivity, to e...Compost amendments have remarkable potential for improving soil structure, porosity and water holding capacity. Soil health is the ability to function as a living system, to sustain plant and animal productivity, to enhance water and air quality, and to promote plant and animal health. Soil health can be estimated by measuring the total living microbial biomass, retained carbon, odor, and texture. Poor or deteriorating soil health is threatening food security. The potential for compost to reverse these negative trends is transformative if means and methods for large scale composting and compost amendments can be developed. A field-scale compost soil amendment project was implemented in Rapid City, South Dakota. The compost was added to a soil plot at 5 wt% and 10 wt% and the results were compared with an adjacent untreated plot without any compost addition. Measurements of soil health characteristics indicate that compost amendments improve soil health, crop yields, and soil water content. Treating soils with compost has the potential to reverse global deteriorating soil health.展开更多
Statistical models using historical data on crop yields and weather to calibrate rela- tively simple regression equations have been widely and extensively applied in previous studies, and have provided a common altern...Statistical models using historical data on crop yields and weather to calibrate rela- tively simple regression equations have been widely and extensively applied in previous studies, and have provided a common alternative to process-based models, which require extensive input data on cultivar, management, and soil conditions. However, very few studies had been conducted to review systematically the previous statistical models for indentifying climate contributions to crop yields. This paper introduces three main statistical methods, i.e., time-series model, cross-section model and panel model, which have been used to identify such issues in the field of agrometeorology. Generally, research spatial scale could be categorized into two types using statistical models, including site scale and regional scale (e.g. global scale, national scale, provincial scale and county scale). Four issues exist in identifying response sensitivity of crop yields to climate change by statistical models. The issues include the extent of spatial and temporal scale, non-climatic trend removal, colinearity existing in climate variables and non-consideration of adaptations. Respective resolutions for the above four issues have been put forward in the section of perspective on the future of statistical models finally.展开更多
A long term fertilization experiment was carried out in an experimental field in Lyczyn near Warsaw, Poland. Application ofmineral fertilizers, especially N fertilizers with and without farmyard manure accelerated th...A long term fertilization experiment was carried out in an experimental field in Lyczyn near Warsaw, Poland. Application ofmineral fertilizers, especially N fertilizers with and without farmyard manure accelerated the acidification process of the soil. Application of 1.6 t CaO ha -1 every four years was essential to maintenance of the soil pH KCl at 5.5~6.6 and base saturation degree above 60%. Application of 50 t farmyard manure ha -1 every 4 years, which contained 46 kg P and 240 kg K, was sufficient to maintain both the K and P fertility of the soil. Besides, it was beneficial to alleviating soil acidification. As a result of long term unbalanced fertilization, yield responses to N, P and K fertilizers increased significantly with time. The efficiency of N from farmyard manure was found to be comparable to that of N fertilizer during 1988~1991.展开更多
Ammonia (NH_3) emissions should be mitigated to improve environmental quality.Croplands are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target yields.Here...Ammonia (NH_3) emissions should be mitigated to improve environmental quality.Croplands are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target yields.Herein,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize rotation.Implementing the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N management.When using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),respectively.Partial manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N management.Straw return exerted a minor effect on NH_3 emissions.These results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.展开更多
This paper reports the results of plot experiments canducted in 1991~1993 on the effects of a new plant growth regulator Shibide (SBD) on the yields of 4 grain crops, 5 vegetables and 2 cash crops. It also reports th...This paper reports the results of plot experiments canducted in 1991~1993 on the effects of a new plant growth regulator Shibide (SBD) on the yields of 4 grain crops, 5 vegetables and 2 cash crops. It also reports the effect of this product on plant growth vigors such as plant height, leaf width and diameter of plant stem.展开更多
Biochar has been widely used for soil improvement,but uncertain results persist due to diverse biochar characteristics,soil properties,and crop responses.Therefore,the effects of biochar on crop yields and soil qualit...Biochar has been widely used for soil improvement,but uncertain results persist due to diverse biochar characteristics,soil properties,and crop responses.Therefore,the effects of biochar on crop yields and soil quality were evaluated using effect size method from 1011 paired data points from field trials,based on a global meta-analysis method.The results indicated that biochar with a higher total phosphorus concentration(≥1.0%),total carbon concentration(≥70%),and specific surface area(≥50 m^(2) g^(‒1))were optimal for improving crop yields.For improving crop yields,biochar made from manure(effect size,42%)outperformed that made from ligneous(22%)or cereal(12%)material.Porous,acidic,or young soil types were optimal for biochar application,while sandy and clay soils were preferred over loam soil.Soils with lower available nitrogen(<80 mg kg^(‒1)),phosphorus(<10 mg kg^(‒1)),potassium(<120 mg kg^(‒1)),pH(<4.5),and cation exchange capacity(<10 cmol kg^(‒1))were more effective on crop yield increases.The effect of biochar on yield was higher for cash crops(oil plants:37%,vegetables:28%)compared to food crops(legumes:26%,maize:20%,wheat:12%,rice:6%),but with no significant effect observed on rice(P=0.788).Finally,biochar increases crop yields by improving soil quality through enhanced levels of soil organic carbon,total nitrogen,ammonium-nitrogen,nitrate-nitrogen,and soil pH while reducing soil bulk density.Our research enhances understanding of the relationships between biochar,soil,and crops,aiding researchers,manufacturers,and farmers in making informed decisions regarding biochar selection,planting locations,and crop choices.展开更多
smallholders in most of Sub-Saharan Africa.These impacts have been more enormous to crop production and other attached livelihoods.However,the comprehensive assessment of these impacts has suffered numerous challenges...smallholders in most of Sub-Saharan Africa.These impacts have been more enormous to crop production and other attached livelihoods.However,the comprehensive assessment of these impacts has suffered numerous challenges because crop productivity is also susceptible to other factors involved in the production process.This study aimed to understand how crop yields are affected by climate change in the semiarid zone of Tanzania.The findings would establish a thorough literature within smallholder adaptation in the area.Furthermore,they will intensify strategies to cope with reduced yields attributed by climate-change impacts.Outcomes:There has been a dramatic decrease in rainfall(R^(2)=0.21)and increase in temperature(R^(2)=0.30).In addition,we found that rainfall and temperature variability had positive(R^(2)~0.5)and negative(R^(2)~0.3)correlations with crop yields,respectively.Discussion:The decline in yields at both local and national levels elevated the magnitude of food shortage and poverty.The increasing climate impacts necessitate undertakings of various studies to plan,design,recommend,and implement various useful adaptation measures,especially in the vulnerable communities.Conclusion:To limit climate effects,we need to increase investments in adaptation and mitigation measures.展开更多
Crop yields and salinity levels in the North Fork of the Red River(North Fork River)basin,located in southwestern Oklahoma and the Texas Panhandle,were analyzed based on the diverse climate in the region.Saline irriga...Crop yields and salinity levels in the North Fork of the Red River(North Fork River)basin,located in southwestern Oklahoma and the Texas Panhandle,were analyzed based on the diverse climate in the region.Saline irrigation water is a major problem in the basin.The Elm Fork Creek flows through salt deposits,making the creek and its receiving stream,the North Fork River,too saline to use for irrigation.This greatly reduces the number of hectares that can be utilized for agricultural crops within the basin.A baseline SWAT model was setup,calibrated and validated to simulate streamflow and wheat and cotton yields.The SWAT model and a regression equation were used to analyze variable weather impacts on crop yields and salinity levels.Using the weather generator WXGEN and 58 years of observed weather data,ten 50-year weather datasets were generated.Output from the weather generator was input into the calibrated SWAT model to simulate wheat and dryland and irrigated cotton yields for the ten weather scenarios.Using an empirical relationship between ionic strength and streamflow,salinity levels were estimated.Though the crop yields varied greatly from year to year,the yields were not significantly different over the 50-year simulation period.The electrical conductivity(EC,expressed in decisiemens per meter or dS/m)at the US Geological Survey gage station just downstream of the salt deposits was significantly different with levels ranging from 40 to 65 dS/m.Though the water in the Elm Fork is much too saline to use for irrigation,the water in the North Fork River may be used as long as the flow rates in the river are greater than 0.60 m3/s.In order to optimize the available cropland,a salinity control must be installed upstream of the salt deposits on the Elm Fork Creek.展开更多
From August 1994 to July 1995, ozone and its precursors were measured in the clean areas of China. The results show that in the period of crop growth, hourly mean ozone concentration, ozone concentration averaged in s...From August 1994 to July 1995, ozone and its precursors were measured in the clean areas of China. The results show that in the period of crop growth, hourly mean ozone concentration, ozone concentration averaged in seven hours of daytime and accumulated ozone concentration in long period have approached or overpassed the harmful level in environmental and health standard of U. S. A. and Canada.展开更多
Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in t...Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in the long term under the combined application of organic and inorganic fertilizers. Three long-term field trials were conducted to investigate the effects of organic amendments on the grain sustainable yield index(SYI), soil fertility index(SFI)and nutrient balance in maize–wheat cropping systems of central and southern China during 1991–2019. Five treatments were included in the trials: 1) no fertilization(control);2) balanced mineral fertilization(NPK);3) NPK plus manure(NPKM);4) high dose of NPK plus manure(1.5NPKM);and 5) NPK plus crop straw(NPKS). Over time, the grain yields of wheat and maize showed an increasing trend in all four fertilization treatments at the Yangling(YL) and Zhengzhou(ZZ) locations, while they declined at Qiyang(QY). The grain yield in the NPKM and 1.5NPKM treatments gradually exceeded that of the NPK and NPKS treatments at the QY site. The largest SYI was recorded in the NPKM treatment across the three sites, suggesting that inorganic fertilizer combined with manure can effectively improve crop yield sustainability. Higher SYI values were recorded at the YL and ZZ sites than at the QY site, possibly because the soil was more acid at QY. The key factors affecting grain yield were soil available phosphorus(AP) and available potassium(AK) at the YL and ZZ sites, and pH and AP at the QY site.All fertilization treatments resulted in soil N and P surpluses at the three sites, but soil K surpluses were recorded only at the QY site. The SFI was greater in the 1.5NPKM, NPKM and NPKS treatments than in the NPK treatment by 13.3–40.0 and 16.4–63.6% at the YL and ZZ sites, respectively, and was significantly higher in the NPKM and 1.5NPKM treatments than in the NPK and NPKS treatments at the QY site. A significant, positive linear relationship was found between SFI and crop yield, and SYI and nutrient balance, indicating that grain yield and its sustainability significantly increased with increasing soil fertility. The apparent N, P and K balances positively affected SFI.This study suggests that the appropriate amount of manure mixed with mineral NPK fertilizer is beneficial to the development of sustainable agriculture, which effectively increases the crop yield and yield sustainability by improving soil fertility.展开更多
The article examines the impact of increased aridization of the territory due to an increase in air temperature,reduced precipitation,and the formation of moisture deficiency on grain yields in Northern Kazakhstan.The...The article examines the impact of increased aridization of the territory due to an increase in air temperature,reduced precipitation,and the formation of moisture deficiency on grain yields in Northern Kazakhstan.The most important result of the work is the revealed inverse relationship between grain yields and the temperature of the growing season:low-yielding years are associated with high temperatures and droughts,and high-yielding years are associated with lower temperatures and an optimal ratio of heat and moisture.The novelty of this study is the use of the method of hydrological and climatic calculations in identifying the nature of temperature variability and precipitation in the territory of Northern Kazakhstan for the modern period(1991–2020)compared with the base period(1961–1990).At all the studied meteorological stations,there is a tendency for the average annual temperature and the temperature of the growing season to increase:in the forest-steppe zone with an average warming intensity of 0.3–0.33℃ per decade;in the steppe zone by 0.2–0.43℃ per decade;and in the growing season by 0.2–0.7℃ per decade.The air temperature in the steppe zone is rising more intensively than in the forest-steppe zone,and precipitation in the forest-steppe zone has changed more than in the steppe zone.An increase in the average annual air temperature during the growing season(May–August),combined with a shortage of atmospheric moisture or a constant amount of it,led to an increase in the degree of aridization of the territory,an increase in the frequency of droughts in the steppe zone of Northern Kazakhstan.展开更多
Surface ozone(O_(3))pollution showed a continuous increasing trend during the recent decades in China,posing an increasing threat to food security.A wide range of yield reductions have been reported and thus more stud...Surface ozone(O_(3))pollution showed a continuous increasing trend during the recent decades in China,posing an increasing threat to food security.A wide range of yield reductions have been reported and thus more studies are needed to narrow down the uncertainty resulting from spatiotemporal accuracy of O_(3) metrics and extrapolation methods.Based on a high spatial resolution(0.1°)hourly surface O_(3) data,here we analyzed the spatiotemporal O_(3) pollution patterns and impacts on yield,production and economic losses for wheat,rice,and maize in China during 2005–2020.The accumulated O_(3) exposure over a threshold of 40 ppb(AOT40)increased by 10%during 2005–2019,and a decrease of 5.56%was observed in 2020 due to the COVID-19 lockdowns.Rising O_(3) pollution reduced national level wheat,rice and maize yields by 14.51%±0.43%,11.10%±0.6%,and 3.99%±0.11%,respectively.A Business-As-Usual projection suggested that the relative yield loss(RYL)would potentially reach 8%–18%at the national scale by 2050 if no emission control is implemented.COVID-19 lockdowns in 2020 led to significantly reduced RYL for maize(0.52%)and rice(2.17%)but not for wheat(0.11%),with the largest reduction(1.88%–9.4%)in North China Plain,highlighting the potential benefits of emission control.Our findings provided robust evidence that rising O_(3) pollution has significantly affected China’s crop yields,production and economic losses,underscoring the urgent need to curb O_(3) pollution to safeguard food security,particularly in densely populated and industrialized regions.展开更多
The increasing frequency of compound extreme events under ongoing climate change threatens global food security.Compared to individual extreme events,the simultaneous occurrence of multiple extreme events can exacerba...The increasing frequency of compound extreme events under ongoing climate change threatens global food security.Compared to individual extreme events,the simultaneous occurrence of multiple extreme events can exacerbate crop yield reductions,yet comprehensive assessments of these compound effects remain limited.To bridge this gap,we applied a linear mixed-effects model to quantify the impacts of individual extreme events(cold days(CD)and killing degree days(KDD))and triple compound extreme events(heatwave and low precipitation(HWLP)and hot-dry-windy(HDW))on the global yields of winter wheat,soybeans,and maize from 1982 to 2016.Our analysis indicated that regions severely impacted by extreme events(exceeding the 95%threshold)experienced total crop yield losses of more than 9.16,24.89,26.69,and 7.12%due to CD,KDD,HWLP,and HDW,respectively.The adverse effects of compound events were particularly pronounced during critical growth stages.HWLP results in yield losses of 9.4%for winter wheat and 6.8%for maize per 10 hours of exposure during the heading to harvesting stages,while soybean yields declined by 8.8%per 10 hours during the planting to three-true-leaf stage.Similarly,KDD caused a 7.4%yield reduction in winter wheat per 10°C day during the heading to harvesting stages,a 9.5%reduction in maize per 10°C day during the planting to jointing stages,and a 3.8%reduction in soybean per 10°C day during the planting to three-true-leaf stages.These findings underscore the substantial contribution of compound extreme events,which are often overlooked in existing risk assessments,in determining the global yields of major staple crops.展开更多
Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cott...Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cotton(Gossypium hirsutum L.)cropping system remains uncertain.The objective of this study was to quantify the long-term(10 years)impact of carbon(C)input on SOC sequestration,soil aggregation and crop yields in a wheat-cotton cropping system in the Yangtze River Valley,China.Five treatments were arranged with a single-factor randomized design as follows:no straw return(Control),return of wheat straw only(Wt),return of cotton straw only(Ct),return of 50%wheat and 50%cotton straw(Wh-Ch)and return of 100%wheat and 100%cotton straw(Wt-Ct).In comparison to the Control,the SOC content increased by 8.4 to 20.2%under straw return.A significant linear positive correlation between SOC sequestration and C input(1.42-7.19 Mg ha^(−1)yr^(−1))(P<0.05)was detected.The percentages of aggregates of sizes>2 and 1-2 mm at the 0-20 cm soil depth were also significantly elevated under straw return,with the greatest increase of the aggregate stability in the Wt-Ct treatment(28.1%).The average wheat yields increased by 12.4-36.0%and cotton yields increased by 29.4-73.7%,and significantly linear positive correlations were also detected between C input and the yields of wheat and cotton.The average sustainable yield index(SYI)reached a maximum value of 0.69 when the C input was 7.08 Mg ha^(−1)yr^(−1),which was close to the maximum value(SYI of 0.69,C input of 7.19 Mg ha^(−1)yr^(-1))in the Wt-Ct treatment.Overall,the return of both wheat and cotton straw was the best strategy for improving SOC sequestration,soil aggregation,yields and their sustainability in the wheat-cotton rotation system.展开更多
It remains unclear whether biochar applications to calcareous soils can improve soil fertility and crop yield. A long-term field experiment was established in 2009 so as to determine the effect of biochar on crop yiel...It remains unclear whether biochar applications to calcareous soils can improve soil fertility and crop yield. A long-term field experiment was established in 2009 so as to determine the effect of biochar on crop yield and soil properties in a calcareous soil. Five treatments were: 1) straw incorporation; 2) straw incorporation with inorganic fertilizer; 3), 4) and 5) straw incorporation with inorganic fertilizer, and biochar at 30, 60, and 90 t ha-l, respectively. The annual yield of either winter wheat or summer maize was not increased significantly following biochar application, whereas the cumulative yield over the first 4 growing seasons was significantly increased. Soil pH, measured in situ, was increased by a maximum of 0.35 units after 2 yr following biochar application. After 3 yr, soil bulk density significantly decreased while soil water holding capacity increased with adding biochar of 90 t ha^-1. Alkaline hydrolysable N decreased but exchangeable K increased due to biochar addition. Olsen-P did not change compared to the treatment without biochar. The results suggested that biochar could be used in calcareous soils without yield loss or significant impacts on nutrient availability.展开更多
基金funded by CAS Project for Young Scientists in Basic Research(YSBR-072-8)National Key Research and Development Program of China(2021YFF1000203 and 2022YFF1001704)。
文摘The crop yields achieved through traditional plant breeding techniques appear to be nearing a plateau.Therefore,it is essential to accelerate advancements in photosynthesis,the fundamental process by which plants convert light energy into chemical energy,to further enhance crop yields.Research focused on improving photosynthesis holds significant promise for increasing sustainable agricultural productivity and addressing challenges related to global food security.This review examines the latest advancements and strategies aimed at boosting crop yields by enhancing photosynthetic efficiency.There has been a linear increase in yield over the years in historically released germplasm selected through traditional breeding methods,and this increase is accompanied by improved photosynthesis.We explore various aspects of the light reactions designed to enhance crop yield,including light harvest efficiency through smart canopy systems,expanding the absorbed light spectrum to include far-red light,optimizing non-photochemical quenching,and accelerating electron transport flux.At the same time,we investigate carbon reactions that can enhance crop yield,such as manipulating Rubisco activity,improving the Calvin-Benson-Bassham cycle,introducing CO_(2)concentrating mechanisms in C_(3)plants,and optimizing carbon allocation.These strategies could significantly impact crop yield enhancement and help bridge the yield gap.
基金supported by the National Key Research and Development Program of China(2022YFC3901103)the National Natural Science Foundation of China(22288102)the Science and Technology Plan Project of the Xinjiang Production and Con-struction Crops(XPCC)(2023AB017-01).
文摘1.The key to achieving China’s dual carbon goals As pointed out in the CO_(2) Emissions in 2023 report released by the International Energy Agency,global carbon dioxide(CO_(2))emis-sions reached 37.4 billion tonnes in 2023[1],setting a new record high.The increase in CO_(2) emissions has exacerbated global warm-ing and led to a series of global climate problems.China is a major emitter of CO_(2).
基金funded by the Tianshan Yingcai Program of the Xinjiang Uygur Autonomous Region(2022TSYCCX0038)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Y2022108)the Postdoctoral Fellowship Program of Chinese Postdoctoral Science Foundation(CPSF)(GZC20232962).
文摘The Tarim River Basin(TRB)is a vast area with plenty of light and heat and is an important base for grain and cotton production in Northwest China.In the context of climate change,however,the increased frequency of extreme weather and climate events is having numerous negative impacts on the region's agricultural production.To better understand how unfavorable climatic conditions affect crop production,we explored the relationship of extreme weather and climate events with crop yields and phenology.In this research,ten indicators of extreme weather and climate events(consecutive dry days(CDD),min Tmax(TXn),max Tmin(TNx),tropical nights(TR),warm days(Tx90p),warm nights(Tn90p),summer days(SU),frost days(FD),very wet days(R95p),and windy days(WD))were selected to analyze the impact of spatial and temporal variations on the yields of major crops(wheat,maize,and cotton)in the TRB from 1990 to 2020.The three key findings of this research were as follows:extreme temperatures in southwestern TRB showed an increasing trend,with higher extreme temperatures at night,while the occurrence of extreme weather and climate events in northeastern TRB was relatively low.The number of FD was on the rise,while WD also increased in recent years.Crop yields were higher in the northeast compared with the southwest,and wheat,maize,and cotton yields generally showed an increasing trend despite an earlier decline.The correlation of extreme weather and climate events on crop yields can be categorized as extreme nighttime temperature indices(TNx,Tn90p,TR,and FD),extreme daytime temperature indices(TXn,Tx90p,and SU),extreme precipitation indices(CDD and R95p),and extreme wind(WD).By using Random Forest(RF)approach to determine the effects of different extreme weather and climate events on the yields of different crops,we found that the importance of extreme precipitation indices(CDD and R95p)to crop yield decreased significantly over time.As well,we found that the importance of the extreme nighttime temperature(TR and TNx)for the yields of the three crops increased during 2005-2020 compared with 1990-2005.The impact of extreme temperature events on wheat,maize,and cotton yields in the TRB is becoming increasingly significant,and this finding can inform policy decisions and agronomic innovations to better cope with current and future climate warming.
基金Support by the Special Fund for Agro-scientific Research in the Public Interest of China(201203030-5)National Natural Science Foundation of China(41201288,41201255,31301284)+2 种基金Key Programs for Science and Technology Development of Henan Province(132102110068)Excellent Youth Science and Technology Foundation of Henan Academy of Agricultural Sciences(2013YQ15)JIRCAS-IARRP collaborative research:Estimation of the Present States of Fertilizer Use and Livestock Production and Their Environmental Load~~
文摘[Objective] Long-term (over 18 years) fertilization experiments were con- ducted to study the responses of crop yields and soil fertility to long-term nutrient lacking at Zhengzhou in China. [Method] The present study consisted of five treat- ments: 1 CK (no fertilizer or manure), (2) NP (nitrogen and phosphorus fertilizer applied), 31 NK (nitrogen and potassium fertilizer applied), 4 PK (phosphorus and potassium fertilizer applied) and :5 NPK (nitrogen, phosphorus and potassium fertil- izer applied). [Result] Lacking of nitrogen or phosphorus led to a low yield; however, there was no significant difference in grain yields between the NP and NPK treat- ments which maintained a higher yield. Receiving no phosphorus, soil available phosphorus content declined to about 2.5 mg/kg. The concentration of soil ex- changeable potassium remained constant at a level of 60 mg/kg under the treat- ments without potassium fertilizer addition. Soil potassium spontaneous supply ca- pacity fluctuated around 100%.[Conclusion] In fluvo-aquic soil, nitrogen and phos- phorus were two key limiting factors to grain yields, biomass and yield component factors of wheat and maize, while potassium was not. However, potassium defi- ciency may occur in the future if there was still no potassium fertilizer applied.
文摘The study attempts to estimate and predict climate impact on crop yields using future temperature projections under two climate emissions scenarios of RCP 4.5 and 8.5 for three different time periods(2030s,2050s and 2080s)across Agro-climatic zones(ACZ)of India.During the period 1966-2011,a significant rise was observed in both the annual mean maximum and minimum temperature across ACZs.Rainfall recorded an annual decline in Himalayan Regions and Gangetic Plains and a rise in Coastal Regions,Plateau&Hills and Western Dry Region.Our results showed high heterogeneity in climate impact on kharif and rabi crop yields(with both negative and positive estimates)across ACZs.It was found that rainfall had a positive effect on most of crop yields,but was not sufficient enough to counterbalance the impact of temperature.Changes in crop yield were more pronounced for higher emission scenario of RCP 8.5.Thus,it was evident that the relative impacts of climate change and the associated vulnerability vary by ACZs,hence comprehensive crop and region-specific adaptation measures should be emphasized that helps in enhancing resilience of agricultural system in short to medium term.
文摘Compost amendments have remarkable potential for improving soil structure, porosity and water holding capacity. Soil health is the ability to function as a living system, to sustain plant and animal productivity, to enhance water and air quality, and to promote plant and animal health. Soil health can be estimated by measuring the total living microbial biomass, retained carbon, odor, and texture. Poor or deteriorating soil health is threatening food security. The potential for compost to reverse these negative trends is transformative if means and methods for large scale composting and compost amendments can be developed. A field-scale compost soil amendment project was implemented in Rapid City, South Dakota. The compost was added to a soil plot at 5 wt% and 10 wt% and the results were compared with an adjacent untreated plot without any compost addition. Measurements of soil health characteristics indicate that compost amendments improve soil health, crop yields, and soil water content. Treating soils with compost has the potential to reverse global deteriorating soil health.
基金National Natural Science Foundation of China, No.41001057 The Science and Technology Strategic Pilot of the Chinese Academy of Sciences, No.XDA05090308+1 种基金 No.XDA05090310 Project Supported by State Key Laboratory of Earth Surface Processes and Resource Ecology, No.2011-KF-06
文摘Statistical models using historical data on crop yields and weather to calibrate rela- tively simple regression equations have been widely and extensively applied in previous studies, and have provided a common alternative to process-based models, which require extensive input data on cultivar, management, and soil conditions. However, very few studies had been conducted to review systematically the previous statistical models for indentifying climate contributions to crop yields. This paper introduces three main statistical methods, i.e., time-series model, cross-section model and panel model, which have been used to identify such issues in the field of agrometeorology. Generally, research spatial scale could be categorized into two types using statistical models, including site scale and regional scale (e.g. global scale, national scale, provincial scale and county scale). Four issues exist in identifying response sensitivity of crop yields to climate change by statistical models. The issues include the extent of spatial and temporal scale, non-climatic trend removal, colinearity existing in climate variables and non-consideration of adaptations. Respective resolutions for the above four issues have been put forward in the section of perspective on the future of statistical models finally.
文摘A long term fertilization experiment was carried out in an experimental field in Lyczyn near Warsaw, Poland. Application ofmineral fertilizers, especially N fertilizers with and without farmyard manure accelerated the acidification process of the soil. Application of 1.6 t CaO ha -1 every four years was essential to maintenance of the soil pH KCl at 5.5~6.6 and base saturation degree above 60%. Application of 50 t farmyard manure ha -1 every 4 years, which contained 46 kg P and 240 kg K, was sufficient to maintain both the K and P fertility of the soil. Besides, it was beneficial to alleviating soil acidification. As a result of long term unbalanced fertilization, yield responses to N, P and K fertilizers increased significantly with time. The efficiency of N from farmyard manure was found to be comparable to that of N fertilizer during 1988~1991.
基金supported by the Hainan Key Research and Development Project, China (ZDYF2021XDNY184)the Hainan Provincial Natural Science Foundation of China (422RC597)+2 种基金the National Natural Science Foundation of China (41830751)the Hainan Major Science and Technology Program, China (ZDKJ2021008)the Hainan University Startup Fund,China (KYQD(ZR)-20098)。
文摘Ammonia (NH_3) emissions should be mitigated to improve environmental quality.Croplands are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target yields.Herein,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize rotation.Implementing the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N management.When using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),respectively.Partial manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N management.Straw return exerted a minor effect on NH_3 emissions.These results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.
文摘This paper reports the results of plot experiments canducted in 1991~1993 on the effects of a new plant growth regulator Shibide (SBD) on the yields of 4 grain crops, 5 vegetables and 2 cash crops. It also reports the effect of this product on plant growth vigors such as plant height, leaf width and diameter of plant stem.
基金supported by The National Key Research and Development Program of China(Grant Nos.2019YFC1906502,and 2019YFC1906504)。
文摘Biochar has been widely used for soil improvement,but uncertain results persist due to diverse biochar characteristics,soil properties,and crop responses.Therefore,the effects of biochar on crop yields and soil quality were evaluated using effect size method from 1011 paired data points from field trials,based on a global meta-analysis method.The results indicated that biochar with a higher total phosphorus concentration(≥1.0%),total carbon concentration(≥70%),and specific surface area(≥50 m^(2) g^(‒1))were optimal for improving crop yields.For improving crop yields,biochar made from manure(effect size,42%)outperformed that made from ligneous(22%)or cereal(12%)material.Porous,acidic,or young soil types were optimal for biochar application,while sandy and clay soils were preferred over loam soil.Soils with lower available nitrogen(<80 mg kg^(‒1)),phosphorus(<10 mg kg^(‒1)),potassium(<120 mg kg^(‒1)),pH(<4.5),and cation exchange capacity(<10 cmol kg^(‒1))were more effective on crop yield increases.The effect of biochar on yield was higher for cash crops(oil plants:37%,vegetables:28%)compared to food crops(legumes:26%,maize:20%,wheat:12%,rice:6%),but with no significant effect observed on rice(P=0.788).Finally,biochar increases crop yields by improving soil quality through enhanced levels of soil organic carbon,total nitrogen,ammonium-nitrogen,nitrate-nitrogen,and soil pH while reducing soil bulk density.Our research enhances understanding of the relationships between biochar,soil,and crops,aiding researchers,manufacturers,and farmers in making informed decisions regarding biochar selection,planting locations,and crop choices.
基金We are indebted to the Chinese Govemment Scholarship(CSC)for providing a scholarship to Mr.Msafri Y.Mkonda.We also wish to thank the research assi stants who were involved in data collection.The study was funded by the College of Resources and Environment,Southwest University and Chongqing Municipal Innovative Talents Program.
文摘smallholders in most of Sub-Saharan Africa.These impacts have been more enormous to crop production and other attached livelihoods.However,the comprehensive assessment of these impacts has suffered numerous challenges because crop productivity is also susceptible to other factors involved in the production process.This study aimed to understand how crop yields are affected by climate change in the semiarid zone of Tanzania.The findings would establish a thorough literature within smallholder adaptation in the area.Furthermore,they will intensify strategies to cope with reduced yields attributed by climate-change impacts.Outcomes:There has been a dramatic decrease in rainfall(R^(2)=0.21)and increase in temperature(R^(2)=0.30).In addition,we found that rainfall and temperature variability had positive(R^(2)~0.5)and negative(R^(2)~0.3)correlations with crop yields,respectively.Discussion:The decline in yields at both local and national levels elevated the magnitude of food shortage and poverty.The increasing climate impacts necessitate undertakings of various studies to plan,design,recommend,and implement various useful adaptation measures,especially in the vulnerable communities.Conclusion:To limit climate effects,we need to increase investments in adaptation and mitigation measures.
文摘Crop yields and salinity levels in the North Fork of the Red River(North Fork River)basin,located in southwestern Oklahoma and the Texas Panhandle,were analyzed based on the diverse climate in the region.Saline irrigation water is a major problem in the basin.The Elm Fork Creek flows through salt deposits,making the creek and its receiving stream,the North Fork River,too saline to use for irrigation.This greatly reduces the number of hectares that can be utilized for agricultural crops within the basin.A baseline SWAT model was setup,calibrated and validated to simulate streamflow and wheat and cotton yields.The SWAT model and a regression equation were used to analyze variable weather impacts on crop yields and salinity levels.Using the weather generator WXGEN and 58 years of observed weather data,ten 50-year weather datasets were generated.Output from the weather generator was input into the calibrated SWAT model to simulate wheat and dryland and irrigated cotton yields for the ten weather scenarios.Using an empirical relationship between ionic strength and streamflow,salinity levels were estimated.Though the crop yields varied greatly from year to year,the yields were not significantly different over the 50-year simulation period.The electrical conductivity(EC,expressed in decisiemens per meter or dS/m)at the US Geological Survey gage station just downstream of the salt deposits was significantly different with levels ranging from 40 to 65 dS/m.Though the water in the Elm Fork is much too saline to use for irrigation,the water in the North Fork River may be used as long as the flow rates in the river are greater than 0.60 m3/s.In order to optimize the available cropland,a salinity control must be installed upstream of the salt deposits on the Elm Fork Creek.
文摘From August 1994 to July 1995, ozone and its precursors were measured in the clean areas of China. The results show that in the period of crop growth, hourly mean ozone concentration, ozone concentration averaged in seven hours of daytime and accumulated ozone concentration in long period have approached or overpassed the harmful level in environmental and health standard of U. S. A. and Canada.
基金supported by the National Natural Science Foundation of China(42177341)the Natural Science Basic Research Program of Shanxi,China(202203021222138).
文摘Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in the long term under the combined application of organic and inorganic fertilizers. Three long-term field trials were conducted to investigate the effects of organic amendments on the grain sustainable yield index(SYI), soil fertility index(SFI)and nutrient balance in maize–wheat cropping systems of central and southern China during 1991–2019. Five treatments were included in the trials: 1) no fertilization(control);2) balanced mineral fertilization(NPK);3) NPK plus manure(NPKM);4) high dose of NPK plus manure(1.5NPKM);and 5) NPK plus crop straw(NPKS). Over time, the grain yields of wheat and maize showed an increasing trend in all four fertilization treatments at the Yangling(YL) and Zhengzhou(ZZ) locations, while they declined at Qiyang(QY). The grain yield in the NPKM and 1.5NPKM treatments gradually exceeded that of the NPK and NPKS treatments at the QY site. The largest SYI was recorded in the NPKM treatment across the three sites, suggesting that inorganic fertilizer combined with manure can effectively improve crop yield sustainability. Higher SYI values were recorded at the YL and ZZ sites than at the QY site, possibly because the soil was more acid at QY. The key factors affecting grain yield were soil available phosphorus(AP) and available potassium(AK) at the YL and ZZ sites, and pH and AP at the QY site.All fertilization treatments resulted in soil N and P surpluses at the three sites, but soil K surpluses were recorded only at the QY site. The SFI was greater in the 1.5NPKM, NPKM and NPKS treatments than in the NPK treatment by 13.3–40.0 and 16.4–63.6% at the YL and ZZ sites, respectively, and was significantly higher in the NPKM and 1.5NPKM treatments than in the NPK and NPKS treatments at the QY site. A significant, positive linear relationship was found between SFI and crop yield, and SYI and nutrient balance, indicating that grain yield and its sustainability significantly increased with increasing soil fertility. The apparent N, P and K balances positively affected SFI.This study suggests that the appropriate amount of manure mixed with mineral NPK fertilizer is beneficial to the development of sustainable agriculture, which effectively increases the crop yield and yield sustainability by improving soil fertility.
文摘The article examines the impact of increased aridization of the territory due to an increase in air temperature,reduced precipitation,and the formation of moisture deficiency on grain yields in Northern Kazakhstan.The most important result of the work is the revealed inverse relationship between grain yields and the temperature of the growing season:low-yielding years are associated with high temperatures and droughts,and high-yielding years are associated with lower temperatures and an optimal ratio of heat and moisture.The novelty of this study is the use of the method of hydrological and climatic calculations in identifying the nature of temperature variability and precipitation in the territory of Northern Kazakhstan for the modern period(1991–2020)compared with the base period(1961–1990).At all the studied meteorological stations,there is a tendency for the average annual temperature and the temperature of the growing season to increase:in the forest-steppe zone with an average warming intensity of 0.3–0.33℃ per decade;in the steppe zone by 0.2–0.43℃ per decade;and in the growing season by 0.2–0.7℃ per decade.The air temperature in the steppe zone is rising more intensively than in the forest-steppe zone,and precipitation in the forest-steppe zone has changed more than in the steppe zone.An increase in the average annual air temperature during the growing season(May–August),combined with a shortage of atmospheric moisture or a constant amount of it,led to an increase in the degree of aridization of the territory,an increase in the frequency of droughts in the steppe zone of Northern Kazakhstan.
基金supported by the National Key R&D Program of China(No.2018YFA0606001)the Ozone Formation Mechanism and Control Strategies Project of Research Center of Eco-Environmental Sciences+3 种基金Chinese Academy of Sciences(No.RCEES-CYZX-2020)the Natural Science Foundation of China(No.42171463)H.T.and S.P.were supported by the US National Science Foundation(No.1903722)Andrew Carnegie Fellowship(No.G-F-19–56910).
文摘Surface ozone(O_(3))pollution showed a continuous increasing trend during the recent decades in China,posing an increasing threat to food security.A wide range of yield reductions have been reported and thus more studies are needed to narrow down the uncertainty resulting from spatiotemporal accuracy of O_(3) metrics and extrapolation methods.Based on a high spatial resolution(0.1°)hourly surface O_(3) data,here we analyzed the spatiotemporal O_(3) pollution patterns and impacts on yield,production and economic losses for wheat,rice,and maize in China during 2005–2020.The accumulated O_(3) exposure over a threshold of 40 ppb(AOT40)increased by 10%during 2005–2019,and a decrease of 5.56%was observed in 2020 due to the COVID-19 lockdowns.Rising O_(3) pollution reduced national level wheat,rice and maize yields by 14.51%±0.43%,11.10%±0.6%,and 3.99%±0.11%,respectively.A Business-As-Usual projection suggested that the relative yield loss(RYL)would potentially reach 8%–18%at the national scale by 2050 if no emission control is implemented.COVID-19 lockdowns in 2020 led to significantly reduced RYL for maize(0.52%)and rice(2.17%)but not for wheat(0.11%),with the largest reduction(1.88%–9.4%)in North China Plain,highlighting the potential benefits of emission control.Our findings provided robust evidence that rising O_(3) pollution has significantly affected China’s crop yields,production and economic losses,underscoring the urgent need to curb O_(3) pollution to safeguard food security,particularly in densely populated and industrialized regions.
基金supported by the National Natural Science Foundation of China(42371483,and 42401573)the Guangdong Basic and Applied Basic Research Foundation,China(2022B1515130001)+2 种基金the Natural Science Foundation of Guangdong Province,China(2024A1515012081 and 2025A1515010770)the Guangzhou Basic and Applied Basic Research Project,China(202201011666)the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(GZB20240880).
文摘The increasing frequency of compound extreme events under ongoing climate change threatens global food security.Compared to individual extreme events,the simultaneous occurrence of multiple extreme events can exacerbate crop yield reductions,yet comprehensive assessments of these compound effects remain limited.To bridge this gap,we applied a linear mixed-effects model to quantify the impacts of individual extreme events(cold days(CD)and killing degree days(KDD))and triple compound extreme events(heatwave and low precipitation(HWLP)and hot-dry-windy(HDW))on the global yields of winter wheat,soybeans,and maize from 1982 to 2016.Our analysis indicated that regions severely impacted by extreme events(exceeding the 95%threshold)experienced total crop yield losses of more than 9.16,24.89,26.69,and 7.12%due to CD,KDD,HWLP,and HDW,respectively.The adverse effects of compound events were particularly pronounced during critical growth stages.HWLP results in yield losses of 9.4%for winter wheat and 6.8%for maize per 10 hours of exposure during the heading to harvesting stages,while soybean yields declined by 8.8%per 10 hours during the planting to three-true-leaf stage.Similarly,KDD caused a 7.4%yield reduction in winter wheat per 10°C day during the heading to harvesting stages,a 9.5%reduction in maize per 10°C day during the planting to jointing stages,and a 3.8%reduction in soybean per 10°C day during the planting to three-true-leaf stages.These findings underscore the substantial contribution of compound extreme events,which are often overlooked in existing risk assessments,in determining the global yields of major staple crops.
基金supported by the National Natural Science Foundation of China(32071968)the Jiangsu Agricultural Science and Technology Innovation Fund,China(CX(22)2015))the Jiangsu Collaborative Innovation Center for Modern Crop Production,China。
文摘Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cotton(Gossypium hirsutum L.)cropping system remains uncertain.The objective of this study was to quantify the long-term(10 years)impact of carbon(C)input on SOC sequestration,soil aggregation and crop yields in a wheat-cotton cropping system in the Yangtze River Valley,China.Five treatments were arranged with a single-factor randomized design as follows:no straw return(Control),return of wheat straw only(Wt),return of cotton straw only(Ct),return of 50%wheat and 50%cotton straw(Wh-Ch)and return of 100%wheat and 100%cotton straw(Wt-Ct).In comparison to the Control,the SOC content increased by 8.4 to 20.2%under straw return.A significant linear positive correlation between SOC sequestration and C input(1.42-7.19 Mg ha^(−1)yr^(−1))(P<0.05)was detected.The percentages of aggregates of sizes>2 and 1-2 mm at the 0-20 cm soil depth were also significantly elevated under straw return,with the greatest increase of the aggregate stability in the Wt-Ct treatment(28.1%).The average wheat yields increased by 12.4-36.0%and cotton yields increased by 29.4-73.7%,and significantly linear positive correlations were also detected between C input and the yields of wheat and cotton.The average sustainable yield index(SYI)reached a maximum value of 0.69 when the C input was 7.08 Mg ha^(−1)yr^(−1),which was close to the maximum value(SYI of 0.69,C input of 7.19 Mg ha^(−1)yr^(-1))in the Wt-Ct treatment.Overall,the return of both wheat and cotton straw was the best strategy for improving SOC sequestration,soil aggregation,yields and their sustainability in the wheat-cotton rotation system.
基金financially supported by the National Natural Science Foundation of China (41171211)
文摘It remains unclear whether biochar applications to calcareous soils can improve soil fertility and crop yield. A long-term field experiment was established in 2009 so as to determine the effect of biochar on crop yield and soil properties in a calcareous soil. Five treatments were: 1) straw incorporation; 2) straw incorporation with inorganic fertilizer; 3), 4) and 5) straw incorporation with inorganic fertilizer, and biochar at 30, 60, and 90 t ha-l, respectively. The annual yield of either winter wheat or summer maize was not increased significantly following biochar application, whereas the cumulative yield over the first 4 growing seasons was significantly increased. Soil pH, measured in situ, was increased by a maximum of 0.35 units after 2 yr following biochar application. After 3 yr, soil bulk density significantly decreased while soil water holding capacity increased with adding biochar of 90 t ha^-1. Alkaline hydrolysable N decreased but exchangeable K increased due to biochar addition. Olsen-P did not change compared to the treatment without biochar. The results suggested that biochar could be used in calcareous soils without yield loss or significant impacts on nutrient availability.