Increasing crop production is necessary to maintain food security for the growing global population.Reducing the gap between actual and potential yield is one of the important ways to increase yield per unit area.Pote...Increasing crop production is necessary to maintain food security for the growing global population.Reducing the gap between actual and potential yield is one of the important ways to increase yield per unit area.Potential yield and the yield gap of soybean were determined for Golestan Province,Iran,using Soybean Simulation Model (SSM-i Crop2) and Geographical Information System (GIS).Information from 24 weather stations and soil data of the region were used.Yield gap and production gap were calculated at county and province levels.The average actual yield of soybean in this province was2.28 t ha^(–1) while the province’s potential yield was 4.73 t ha^(–1),so the yield gap was estimated 2.44 t ha^(–1).Thus,there is a great potential for increasing soybean yield in Golestan,which is possible through improving crop management of soybean in farmers’fields.The average water productivity of soybean was estimated to be 0.81 kg m^(–3).Spatial distribution of water productivity in soybean farms showed that the highest and the lowest water productivities (0.99 and 0.44 kg m^(–3)) were in western and eastern regions of the province,respectively,in accordance to vapour pressure deficit.It was concluded that soybean production in the province could increase by 66%(from 109 970 to 182 170 tons) if 80% of the current yield gap could be removed.展开更多
The role of energy crops in reducing fossil energy use and greenhouse gas emission is much debated. To improve decision making on the use of crops for producing bioenergy, a tool (Energy Crop Simulation Model or E-CRO...The role of energy crops in reducing fossil energy use and greenhouse gas emission is much debated. To improve decision making on the use of crops for producing bioenergy, a tool (Energy Crop Simulation Model or E-CROP) has been developed to calculate 1) sustainable crop dry matter yield levels as function of agricultural inputs, and 2) gross and net energy yield and greenhouse gas emission reduction, covering the entire bioenergy production chain from sowing to distribution of bioenergy. E-CROP can be applied to a wide range of crops, soils, climatic conditions, management choices, and conversion technologies. This paper describes E-CROP and focuses on its application on four arable crops, as cultivated on two contrasting sites in the Netherlands (potato and sugar beet for bioethanol, winter oilseed rape for biodiesel and silage maize for bioelectricity) and on the effect of crop management (viz. irrigation and nitrogen fertilisation). In all situations, gross energy output exceeded total energy input. Calculated for an average situation, net energy yield ranged from 45 to 140 GJ.ha-1. Lowering irrigation and/or fertilisation input levels generally resulted in a reduction of net energy yields. The net reduction of greenhouse gas emissions in the average situation ranged from 0.60 to 6.5 t CO2-eq.ha-1. In general, N2O emission from nitrogen fertiliser caused large variations in the net reduction of greenhouse gas emission, which even became negative in some situations. Lowering nitrogen fertilisation to levels that are suboptimal for net energy yields enhanced the net reduction in greenhouse gas emission, implicating that both goals cannot be optimised simultaneously. Agricultural knowledge is important for optimising the outputs of bioenergy production chains.展开更多
Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objective...Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objectives of this study were to investigate the potential use of a modified WOFOST model for predicting jujube yield by introducing tree age as a key parameter.The model was established using data collected from dedicated field experiments performed in 2016-2018.Simulated growth dynamics of dry weights of leaves,stems,fruits,total biomass and leaf area index(LAI) agreed well with measured values,showing root mean square error(RMSE) values of 0.143,0.333,0.366,0.624 t ha^-1 and 0.19,and R2 values of 0.947,0.976,0.985,0.986 and 0.95,respectively.Simulated phenological development stages for emergence,anthesis and maturity were 2,3 and 3 days earlier than the observed values,respectively.In addition,in order to predict the yields of trees with different ages,the weight of new organs(initial buds and roots) in each growing season was introduced as the initial total dry weight(TDWI),which was calculated as averaged,fitted and optimized values of trees with the same age.The results showed the evolution of the simulated LAI and yields profiled in response to the changes in TDWI.The modelling performance was significantly improved when it considered TDWI integrated with tree age,showing good global(R2≥0.856,RMSE≤0.68 t ha^-1) and local accuracies(mean R2≥0.43,RMSE≤0.70 t ha^-1).Furthermore,the optimized TDWI exhibited the highest precision,with globally validated R2 of 0.891 and RMSE of 0.591 t ha^-1,and local mean R2 of 0.57 and RMSE of 0.66 t ha^-1,respectively.The proposed model was not only verified with the confidence to accurately predict yields of jujube,but it can also provide a fundamental strategy for simulating the growth of other fruit trees.展开更多
The system of rice intensification (SRI) is reported to have advantages like lower seed requirement,less pest attack,shorter crop duration,higher water use efficiency and the ability to withstand higher degree of mo...The system of rice intensification (SRI) is reported to have advantages like lower seed requirement,less pest attack,shorter crop duration,higher water use efficiency and the ability to withstand higher degree of moisture stress than traditional method of rice cultivation.With this background,SRI was compared with traditional transplanting technique at Indian Agricultural Research Institute,New Delhi,India during two wet seasons (2009-2011).In the experiment laid out in a factorial randomized block design,two methods of rice cultivation [conventional transplanting (CT) and SRI] and two rice varieties (Pusa Basmati 1 and Pusa 44) were used under seven crop nutrition treatments,viz.T 1,120 kg/hm2 N,26.2 kg/hm2 P and 33 kg/hm2 K;T 2,20 t/hm2 farmyard manure (FYM);T 3,10 t/hm2 FYM+ 60 kg/hm2 N;T 4,5 t/hm2 FYM+ 90 kg/hm2 N;T 5,5 t/hm2 FYM+ 60 kg/hm2 N+ 1.5 kg/hm2 blue green algae (BGA);T 6,5 t/hm2 FYM+ 60 kg/hm2 N+ 1.0 t/hm2 Azolla,and T 7,N 0 P 0 K 0 (control,no NPK application) to study the effect on seed quality,yield and water use.In SRI,soil was kept at saturated moisture condition throughout vegetative phase and thin layer of water (2-3 cm) was maintained during the reproductive phase of rice,however,in CT,standing water was maintained in crop growing season.Results revealed that CT and SRI gave statistically at par grain yield but straw yield was significantly higher in CT as compared to SRI.Seed quality was superior in SRI as compared to CT.Integrated nutrient management (INM) resulted in higher plant height with longer leaves than chemical fertilizer alone in both the rice varieties.Grain yield attributes such as number of effective tillers per hill,panicle length and panicle weight of rice in both the varieties were significantly higher in INM as compared to chemical fertilizer alone.Grain yields of both the varieties were the highest in INM followed by the recommended doses of chemical fertilizer.The grain yield and its attributes of Pusa 44 were significantly higher than those of Pusa Basmati 1.The seed quality parameters like germination rate and vigor index as well as N uptake and soil organic carbon content were higher in INM than those in chemical fertilizer alone.CT rice used higher amount of water than SRI,with water saving of 37.6% to 34.5% in SRI.Significantly higher water productivity was recorded in SRI as compared to CT rice.展开更多
A field study was scheduled to estimate the impact of intercropping of pearl millet with cowpea on forage yield and quality at Agronomy Research Farm, University of Agriculture, Faisalabad. It was done in kharif seaso...A field study was scheduled to estimate the impact of intercropping of pearl millet with cowpea on forage yield and quality at Agronomy Research Farm, University of Agriculture, Faisalabad. It was done in kharif season 2016. Randomized complete block design was used to conduct this experiment. It has three replications. The size of net plot is 3.6 m × 6 m. It comprised of five treatments (T1 = one row of millet alternating with one row of cowpea (1M:1C), T2 = two rows of millet alternating with one row of cowpea (2M:1C), T3 = one row of millet alternating with two rows of cowpea (1M:2C), T4 = sole millet, T5 = sole cowpea). We found that intercropping significantly effected the yield and quality of forage. Intercropping system had significant effects on nutritive value of forage crop. Within various treatments of intercropping, it is evident that treatment T2 (two rows of millet alternating with one row of cowpea) gives maximum total dry matter yield (9.68 t ha-1). It was then tracked by treatment T1 (one row of millet alternating with one row of cowpea) and treatment T3 (one row of millet alternating with two rows of cowpea) producing dry matter yield (9.07 t ha-1 and 8.33 t ha-1, respectively). Based on high grain and suitable environmental condition, intercrop productivity compared to sole crop could be selected for improving the productivity of millet/cowpea mixture in the Punjab.展开更多
Accurate crop growth monitoring and yield forecasting have important implications for food security and agricultural macro-control. Crop simulation and satellite remote sensing have their own advantages, combining the...Accurate crop growth monitoring and yield forecasting have important implications for food security and agricultural macro-control. Crop simulation and satellite remote sensing have their own advantages, combining the two can improve the real-time mechanism and accuracy of agricultural monitoring and evaluation. The research is based on the MERSI data carried by China’s new generation Fengyun-3 meteorological satellite, combined with the US ALMANAC crop model, established the NDVI-LAI model and realized the acquisition of LAI data from point to surface. Because of the principle of the relationship between the morphological changes of LAI curve and the growth of crops, an index that can be used to determine the growth of crops is established to realize real-time, dynamic and wide-scale monitoring of winter wheat growth. At the same time, the index was used to select the different key growth stages of winter wheat for yield estimation. The results showed that the relative error of total yield during the filling period was low, nearly 5%. The research results show that the combination of domestic meteorological satellite Fengyun-3 and ALMANAC crop model for crop growth monitoring and yield estimation is feasible, and further expands the application range of domestic satellites.展开更多
Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated t...Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated the effect of seed priming and irrigation on crop establishment, tillering, agronomic traits, paddy yield, grain quality and water productivity of direct seeded rice in alternate wetting and drying (DSR-AWD) in comparison with direct seeded rice at field capacity (DSR- FC). Seed priming treatments were osmo-priming with KCI (2.2%), CaCI2 (2.2%) and moringa leaf extracts (MLE, 3.3%) including hydro-priming as control. Among the treatments, seed osmo-primed with MLE emerged earlier and had higher final emergence, followed by osmo-priming with CaCI2. Tillering emergence rate and number of tillers per plant were the highest for seed priming with CaCI2 in DSR- AWD. Total productive and non-productive tillers, panicle length, biological and grain yields, harvest index were highest for seed priming with MLE or CaCI2 in DSR-AWD. Similarly, grain quality, estimated in terms of normal grains, abortive and chalky grains, was also the highest in DSR-AWD with MLE osmo-priming. Benefit cost ratio and water productivity was also the highest in DSR-AWD for seed priming with MLE. In conclusion, seed priming with MLE or CaCI2 can be successfully employed to improve the direct seeded rice performance when practiced with alternate wetting and drying irrigation.展开更多
Improved utilization of rice(Oryza sativa L.)straw and Chinese milk vetch(Astragalus sinicus L.,vetch)has positive effects on rice production.So far,few studies have investigated the productivity of vetch under differ...Improved utilization of rice(Oryza sativa L.)straw and Chinese milk vetch(Astragalus sinicus L.,vetch)has positive effects on rice production.So far,few studies have investigated the productivity of vetch under different residue management practices in double-rice cropping system.The effects of rice straw on the growth and nutrient accumulation of vetch across seven years(2011–2017)and the subsequent effects of rice straw and vetch on two succeeding rice crops in a vetch–rice–rice cropping system,with the vetch established by relay cropping,were examined.The seven-year double-rice experiment consisted of the following treatments:(1)100%chemical fertilizer(F-F100);(2)only vetch without chemical fertilizer(M-Con);(3)80%chemical fertilizer plus vetch plus a low-cutting height(low-retained stubble)with the removal of straw(M-F80);(4)80%chemical fertilizer plus vetch plus a low-cutting height with the retention of straw(M-F80-LR);(5)80%chemical fertilizer plus vetch plus a high-cutting height(high-retained stubble)with the retention of straw(M-F80-HR);and(6)no fertilizer(F-Con).The yields of the two rice crops after vetch were not affected by either the cutting height of stubble with retention of straw or by the management of straw(retention vs.removal)with low-cutting height of stubble.The yields of the two rice crops after vetch were significantly higher for M-F80-HR than for M-F80-LR,but the relative contributions of the high-cutting height and straw retention to the higher rice yield could not be determined in this study.The yield stability of the double-rice grain in M-F80-HR was also increased,as determined by a sustainable yield index.Significant increases in vetch biomass and nutrient uptake were observed in the fertilized treatments during the rice season compared with the unfertilized treatments.In M-F80-HR plots,improvements in the growing environment of the vetch by conserving soil water content were associated with the highest vetch biomass,nutrient uptake,and yield stability of vetch biomass.These increased nutrient inputs partially replaced the demand for chemical fertilizer and stimulated the rice yields.It can be concluded that retaining higher-cutting stubble residues with straw retention could be the best straw management practice for increasing the vetch biomass and nutrient use efficiency,thereby allowing utilization of high-cutting height with retention of straw and vetch to improve the stability of rice productivity in a double-rice cropping system.展开更多
The contribution percentage of inherent soil productivity(CPISP)refers to the ratio of crop yields under no-fertilization versus under conventional fertilization with the same field management.CPISP is a comprehensive...The contribution percentage of inherent soil productivity(CPISP)refers to the ratio of crop yields under no-fertilization versus under conventional fertilization with the same field management.CPISP is a comprehensive measure of soil fertility.This study used 1086 on-farm trials(from 1984-2013)and 27 long-term field experiments(from 1979-2013)to quantify changes in CPISP.Here,we present CPISP3 values,which reflect the CPISP states during the first three years after site establishment,for a series of sites at different locations in China collected in 1984-1990(the 1980s),1996-2000(the 1990s),and 2004-2013(the 2000s).The results showed that the average CPISP3 value for three crops(wheat,rice,and maize)was 53.8%.Historically,the CPISP3 in the 1990s(57.5%)was much higher than those in the 1980s(50.3%),and the 2000s(52.0%)(P≤0.05).Long-term no-fertilization caused CPISP levels to gradually decline and then stabilize;for example,in a mono-cropping system with irrigation,the CPISP values in Northwest and Northeast China declined by 4.5 and 4.0%,respectively,each year for the first ten years,but subsequently,the CPISP values stabilized.In contrast,the CPISP for upland crops in double-cropping systems continued to decrease at a rate of 1.1%per year.The CPISP for upland-paddy cropping decreased very slowly(0.07%per year),whereas the CPISP for paddy cropping decreased sharply(3.1%per year,on average)for the first two years and then remained steady during the following years.Therefore,upland crops in double-cropping systems consume the most inherent soil productivity,whereas paddy fields are favourable for maintaining a high level of CPISP.Overall,our results demonstrate a need to further improve China’s CPISP3 values to meet growing productivity demands.展开更多
For making rational and scientific land-use planning,an inventory indicator of land productivity subject to biophysical limitations and human disturbance is required.This study introduces agricultural land productivit...For making rational and scientific land-use planning,an inventory indicator of land productivity subject to biophysical limitations and human disturbance is required.This study introduces agricultural land productivity(ALP)as the dynamic indicator to measure land productivity,involving factors that affect agricultural production,such as characteristics of climate,soil,and terrain.As a case study of this dynamic indicator,ALP was estimated at county level and aggregated into provincial level in the whole of China.The result shows that ALP increased during 2000-2010 in China,and the ratios of ALP to the actual grain yield were 65.40%and 66.38%in the years 2000 and 2005,respectively.The ALP is an effective dynamic indicator to estimate the land productivity and to represent the basic conditions about the supply of water,energy,nutrients,and the physical basis for plant growth,as well as the local input.ALP estimation could provide supporting information for policy-making about land production planning and land-use management.展开更多
Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria L.and Tecomella undulata L.and yields of Vigna radiata(L) in agroforestry systems in degraded lands of Indian Desert.Pote...Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria L.and Tecomella undulata L.and yields of Vigna radiata(L) in agroforestry systems in degraded lands of Indian Desert.Potential competition for resource between the trees and associated crop was analyzed by measuring soil water contents, soil organic matters and NH4-N at different depths of soil layers i.e., 0-25 cm, 25-50 cm and 50-75 cm in the experimental plots.The plots size were 16 m × 18 m(D1), 20 m × 18 m(D2) and 32 m × 18 m(D3) with tree densities of 208, 138 and 104 trees·ha-1 after June 2002, respectively.Results showed that tree height increased by 3% to 7% during June 2002 to June 2004.Collar diameter increased by 30% and 11% in D1, 23% and 19% in D2 and 18% and 36% in D3 plots, respectively, in P.cineraria and T.undulata in two years period.The increase in crown diameter was 9% to 18% in P.cineraria and 11% to 16% in T.undulata.Tree growth was relatively greater in 2002 than in 2003.Yield of V.radiata increased linearly from D1 to D3 plots.Lowest soil water content at 1 m distance from tree base indicated greater utilization of soil water within the tree rooting zone.Concentrations of soil organic matters and NH4-N were the highest(p<0.05) in 0-25 cm soil layer.P.cineraria was more beneficial than T.undulata in improving soil conditions and increasing crop yield by 11.1% and thus more suitable for its integration in agricultural land.The yield of agricultural crop increased when density of tree species was appropriate(i.e., optimum tree density), though it varied with tree size and depended upon resource availability.The result indicated bio-economic benefits of optimum density of P.cineraria and T.undulata over traditional practices of maintaining random trees in farming system in arid zones.展开更多
In recent years, conventional rice production technologies have been leading to deterioration of soil health and declining farm profitability due to high inputs of water and labor. Conservation agriculture (CA) base...In recent years, conventional rice production technologies have been leading to deterioration of soil health and declining farm profitability due to high inputs of water and labor. Conservation agriculture (CA) based resource-conserving technologies i.e. zero-tillage (ZT), raised-bed planting and direct-seeded rice (DSR) have shown promise as alternatives to conventional production technologies to overcome these problems. Present study was undertaken during 2009-2012 to establish an understanding of how permanent raised bed cropping system could be practiced to save water at the field application level to improve water productivity and also have the capability to enhance productivity, profitability and soil physical quality. The results showed that among different crop establishment techniques, conventional-tilled puddle transplanted rice (CT-TPR) required 14%-25% more water than other techniques. Compared with the CT-TPR system, zero till direct-seeded rice (ZT-DSR) consumed 6%-10%less water with almost equal system productivity and demonstrated higher water productivity. Wide raised beds saved about 15%-24% water and grain yield decrease of about 8%. Direct-seeded rice after ZT or reduced tillage or on unpuddled soil provided more net income than CT-TPR. The CT-TPR system had higher bulk density and penetration resistance due to compaction caused by the repeated wet tillage in rice. The steady-state infiltration rate and soil aggregation (〉 0.25 mm) were higher under permanent beds and ZT and lower in the CT-TPR system. Under CT-TPR, soil aggregation was static across seasons, whereas it improved under no-till and permanent beds. Similarly, mean weight diameter of aggregates was higher under ZT and permanent beds and increased over time. The study reveals that to sustain the rice productivity, CA-based planting techniques can be more viable options. However, the long-term effects of these alternative technologies need to be studied under varying agro-ecologies in western Uttar Pradesh, India.展开更多
Potato productivity in the northeastern US has been relatively constant for over 50 years, raising questions about what factors are limiting productivity. Research was initiated in 2004 to identify key constraints to ...Potato productivity in the northeastern US has been relatively constant for over 50 years, raising questions about what factors are limiting productivity. Research was initiated in 2004 to identify key constraints to potato productivity by evaluating Status Quo (SQ), Soil Conserving (SC), and Soil Improving (SI) cropping systems under both rainfed and irrigated management, and it was found that addition of compost or irrigation substantially increased yield. In this study, we employed partial budgeting to determine cost differences and their impact on net revenue for these cropping systems. Differences in systems were primarily associated with rotation length, tillage operations, compost and application expenses, and water management practices. When compost (as composted dairy manure) was annually applied at 19 Mg haf-1 and evaluated over the entire 3-year crop rotation cycle, the compost-amended rainfed SI system was more expensive to maintain than the irrigated SC system if compost cost exceeded $3.63 Mg-1. Average marketable yields were used to calculate gross and net revenue for each system. Because average potato yield for the irrigated SQ system (28.4 Mg·ha-1) equaled that in the rainfed SI system (28.3 Mg·ha-1), we were able to compare cost of irrigation versus compost for achieving comparable yield. The compost-amended SI system under rainfed management generated more net revenue from the potato crop than the irrigated SQ system when compost costs were less than $7.42 Mg-1. When compared to the commonly used rainfed SQ system, rainfed SI achieved higher net revenue as long as compost cost was less than $22.95 Mg-1. The rainfed SI system achieved higher net revenue than the irrigated SC system when compost cost was $9.43 Mg-1or less, but generated greater net revenue than the rainfed SC system regardless of compost costs, due to substantially higher yields associated with compost amendment. This investigation demonstrates that compost is a potentially viable substitute to irrigation for potato in the northeastern US;however, such potential is highly dependent on suitable compost sources and application costs.展开更多
Building a more resilient response system to climate change for sustainable development and reducing uncertainty in China’s food markets,requires access to historical research gaps and mapping future research progres...Building a more resilient response system to climate change for sustainable development and reducing uncertainty in China’s food markets,requires access to historical research gaps and mapping future research progress for decision making.However,the lack of quantitative and objective analyses to ensure the stability and development of agroecosystems increases the complexity of agro-climatic mechanisms,which leads to uncertainty and undesirable consequences.In this paper,we review the characteristics of climate change in China(1951–2020),reveal the mechanisms of agroecosystem structure in response to climate,and identify challenges and opportunities for future efforts in the context of research progress.The aim is to improve the scientific validity and relevance of future research by clarifying agro-climatic response mechanisms.The results show that surface temperature,precipitation,and frequency of extreme weather events have increased to varying degrees in major agricultural regions of China in 1951–2020.And they have strong geographic variation,which has resulted in droughts in the north and floods in the south.Moreover,climate change has complicated the mechanisms of soil moisture,Net Primary Productivity(NPP),soil carbon pool,and crop pest structure in agroecosystems.This lends to a reduction in soil water holding capacity,NPP,soil carbon content,and the number of natural enemies of diseases and insects,which in turn affects crop yields.However,human interventions can mitigate the deterioration of these factors.We have also realized that the methodology and theory of historical research poses a great challenge to future agroecosystem.Historical and projected climate trends identified current gaps in interdisciplinary integration and multidisciplinary research required to manage diverse spatio-temporal climate change impacts on agroecosystems.Future efforts should highlight integrated management and decision making,multidisciplinary big data coupling,and numerical simulations to ensure sustainable agricultural development,ecological security,and food security in China.展开更多
To investigate the effects of crop rotation on oilseed flax growth and yield,three season experiments were carried out in semi-arid area of Dingxi,Gansu from 2017 to 2019.The designed 6 rotational systems were FFF(fla...To investigate the effects of crop rotation on oilseed flax growth and yield,three season experiments were carried out in semi-arid area of Dingxi,Gansu from 2017 to 2019.The designed 6 rotational systems were FFF(flax-flaxflax),PFF(potato-flax-flax),WPF(wheat-potato-flax),FPF(flax-potato-flax),PWF(potato-wheat-flax)and FWF(flax-wheat-flax).Flax growth and yield investigation results showed that crop rotation increased leaf area duration,dry matter accumulation,seed nitrogen accumulation,water and nitrogen used efficiency,compared with continuous cropping of flax.Flaxseed yields in rotation systems were 22.23%–44.11%greater than those of continuous cropping system.Those in wheat and potato stubbles had higher tiller number(21.43%and 29.46%),more branches(14.24%and 6.97%),effective capsules(26.35%and 28.79%),higher water use efficiency(40.26%and 33.5%),higher nitrogen partial factor productivity(33.85%and 31.46%)and dry matter(41.98%and 25.47%)than those in oilseed flax stubble.It concluded that crop rotation system was an effective measure for oilseed flax productivity in semi-arid area by improving yield components and promoting biomass.展开更多
文摘Increasing crop production is necessary to maintain food security for the growing global population.Reducing the gap between actual and potential yield is one of the important ways to increase yield per unit area.Potential yield and the yield gap of soybean were determined for Golestan Province,Iran,using Soybean Simulation Model (SSM-i Crop2) and Geographical Information System (GIS).Information from 24 weather stations and soil data of the region were used.Yield gap and production gap were calculated at county and province levels.The average actual yield of soybean in this province was2.28 t ha^(–1) while the province’s potential yield was 4.73 t ha^(–1),so the yield gap was estimated 2.44 t ha^(–1).Thus,there is a great potential for increasing soybean yield in Golestan,which is possible through improving crop management of soybean in farmers’fields.The average water productivity of soybean was estimated to be 0.81 kg m^(–3).Spatial distribution of water productivity in soybean farms showed that the highest and the lowest water productivities (0.99 and 0.44 kg m^(–3)) were in western and eastern regions of the province,respectively,in accordance to vapour pressure deficit.It was concluded that soybean production in the province could increase by 66%(from 109 970 to 182 170 tons) if 80% of the current yield gap could be removed.
文摘The role of energy crops in reducing fossil energy use and greenhouse gas emission is much debated. To improve decision making on the use of crops for producing bioenergy, a tool (Energy Crop Simulation Model or E-CROP) has been developed to calculate 1) sustainable crop dry matter yield levels as function of agricultural inputs, and 2) gross and net energy yield and greenhouse gas emission reduction, covering the entire bioenergy production chain from sowing to distribution of bioenergy. E-CROP can be applied to a wide range of crops, soils, climatic conditions, management choices, and conversion technologies. This paper describes E-CROP and focuses on its application on four arable crops, as cultivated on two contrasting sites in the Netherlands (potato and sugar beet for bioethanol, winter oilseed rape for biodiesel and silage maize for bioelectricity) and on the effect of crop management (viz. irrigation and nitrogen fertilisation). In all situations, gross energy output exceeded total energy input. Calculated for an average situation, net energy yield ranged from 45 to 140 GJ.ha-1. Lowering irrigation and/or fertilisation input levels generally resulted in a reduction of net energy yields. The net reduction of greenhouse gas emissions in the average situation ranged from 0.60 to 6.5 t CO2-eq.ha-1. In general, N2O emission from nitrogen fertiliser caused large variations in the net reduction of greenhouse gas emission, which even became negative in some situations. Lowering nitrogen fertilisation to levels that are suboptimal for net energy yields enhanced the net reduction in greenhouse gas emission, implicating that both goals cannot be optimised simultaneously. Agricultural knowledge is important for optimising the outputs of bioenergy production chains.
基金supported by the National Natural Science Foundation of China(41561088 and 61501314)the Science&Technology Nova Program of Xinjiang Production and Construction Corps,China(2018CB020)
文摘Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objectives of this study were to investigate the potential use of a modified WOFOST model for predicting jujube yield by introducing tree age as a key parameter.The model was established using data collected from dedicated field experiments performed in 2016-2018.Simulated growth dynamics of dry weights of leaves,stems,fruits,total biomass and leaf area index(LAI) agreed well with measured values,showing root mean square error(RMSE) values of 0.143,0.333,0.366,0.624 t ha^-1 and 0.19,and R2 values of 0.947,0.976,0.985,0.986 and 0.95,respectively.Simulated phenological development stages for emergence,anthesis and maturity were 2,3 and 3 days earlier than the observed values,respectively.In addition,in order to predict the yields of trees with different ages,the weight of new organs(initial buds and roots) in each growing season was introduced as the initial total dry weight(TDWI),which was calculated as averaged,fitted and optimized values of trees with the same age.The results showed the evolution of the simulated LAI and yields profiled in response to the changes in TDWI.The modelling performance was significantly improved when it considered TDWI integrated with tree age,showing good global(R2≥0.856,RMSE≤0.68 t ha^-1) and local accuracies(mean R2≥0.43,RMSE≤0.70 t ha^-1).Furthermore,the optimized TDWI exhibited the highest precision,with globally validated R2 of 0.891 and RMSE of 0.591 t ha^-1,and local mean R2 of 0.57 and RMSE of 0.66 t ha^-1,respectively.The proposed model was not only verified with the confidence to accurately predict yields of jujube,but it can also provide a fundamental strategy for simulating the growth of other fruit trees.
文摘The system of rice intensification (SRI) is reported to have advantages like lower seed requirement,less pest attack,shorter crop duration,higher water use efficiency and the ability to withstand higher degree of moisture stress than traditional method of rice cultivation.With this background,SRI was compared with traditional transplanting technique at Indian Agricultural Research Institute,New Delhi,India during two wet seasons (2009-2011).In the experiment laid out in a factorial randomized block design,two methods of rice cultivation [conventional transplanting (CT) and SRI] and two rice varieties (Pusa Basmati 1 and Pusa 44) were used under seven crop nutrition treatments,viz.T 1,120 kg/hm2 N,26.2 kg/hm2 P and 33 kg/hm2 K;T 2,20 t/hm2 farmyard manure (FYM);T 3,10 t/hm2 FYM+ 60 kg/hm2 N;T 4,5 t/hm2 FYM+ 90 kg/hm2 N;T 5,5 t/hm2 FYM+ 60 kg/hm2 N+ 1.5 kg/hm2 blue green algae (BGA);T 6,5 t/hm2 FYM+ 60 kg/hm2 N+ 1.0 t/hm2 Azolla,and T 7,N 0 P 0 K 0 (control,no NPK application) to study the effect on seed quality,yield and water use.In SRI,soil was kept at saturated moisture condition throughout vegetative phase and thin layer of water (2-3 cm) was maintained during the reproductive phase of rice,however,in CT,standing water was maintained in crop growing season.Results revealed that CT and SRI gave statistically at par grain yield but straw yield was significantly higher in CT as compared to SRI.Seed quality was superior in SRI as compared to CT.Integrated nutrient management (INM) resulted in higher plant height with longer leaves than chemical fertilizer alone in both the rice varieties.Grain yield attributes such as number of effective tillers per hill,panicle length and panicle weight of rice in both the varieties were significantly higher in INM as compared to chemical fertilizer alone.Grain yields of both the varieties were the highest in INM followed by the recommended doses of chemical fertilizer.The grain yield and its attributes of Pusa 44 were significantly higher than those of Pusa Basmati 1.The seed quality parameters like germination rate and vigor index as well as N uptake and soil organic carbon content were higher in INM than those in chemical fertilizer alone.CT rice used higher amount of water than SRI,with water saving of 37.6% to 34.5% in SRI.Significantly higher water productivity was recorded in SRI as compared to CT rice.
文摘A field study was scheduled to estimate the impact of intercropping of pearl millet with cowpea on forage yield and quality at Agronomy Research Farm, University of Agriculture, Faisalabad. It was done in kharif season 2016. Randomized complete block design was used to conduct this experiment. It has three replications. The size of net plot is 3.6 m × 6 m. It comprised of five treatments (T1 = one row of millet alternating with one row of cowpea (1M:1C), T2 = two rows of millet alternating with one row of cowpea (2M:1C), T3 = one row of millet alternating with two rows of cowpea (1M:2C), T4 = sole millet, T5 = sole cowpea). We found that intercropping significantly effected the yield and quality of forage. Intercropping system had significant effects on nutritive value of forage crop. Within various treatments of intercropping, it is evident that treatment T2 (two rows of millet alternating with one row of cowpea) gives maximum total dry matter yield (9.68 t ha-1). It was then tracked by treatment T1 (one row of millet alternating with one row of cowpea) and treatment T3 (one row of millet alternating with two rows of cowpea) producing dry matter yield (9.07 t ha-1 and 8.33 t ha-1, respectively). Based on high grain and suitable environmental condition, intercrop productivity compared to sole crop could be selected for improving the productivity of millet/cowpea mixture in the Punjab.
文摘Accurate crop growth monitoring and yield forecasting have important implications for food security and agricultural macro-control. Crop simulation and satellite remote sensing have their own advantages, combining the two can improve the real-time mechanism and accuracy of agricultural monitoring and evaluation. The research is based on the MERSI data carried by China’s new generation Fengyun-3 meteorological satellite, combined with the US ALMANAC crop model, established the NDVI-LAI model and realized the acquisition of LAI data from point to surface. Because of the principle of the relationship between the morphological changes of LAI curve and the growth of crops, an index that can be used to determine the growth of crops is established to realize real-time, dynamic and wide-scale monitoring of winter wheat growth. At the same time, the index was used to select the different key growth stages of winter wheat for yield estimation. The results showed that the relative error of total yield during the filling period was low, nearly 5%. The research results show that the combination of domestic meteorological satellite Fengyun-3 and ALMANAC crop model for crop growth monitoring and yield estimation is feasible, and further expands the application range of domestic satellites.
文摘Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated the effect of seed priming and irrigation on crop establishment, tillering, agronomic traits, paddy yield, grain quality and water productivity of direct seeded rice in alternate wetting and drying (DSR-AWD) in comparison with direct seeded rice at field capacity (DSR- FC). Seed priming treatments were osmo-priming with KCI (2.2%), CaCI2 (2.2%) and moringa leaf extracts (MLE, 3.3%) including hydro-priming as control. Among the treatments, seed osmo-primed with MLE emerged earlier and had higher final emergence, followed by osmo-priming with CaCI2. Tillering emergence rate and number of tillers per plant were the highest for seed priming with CaCI2 in DSR- AWD. Total productive and non-productive tillers, panicle length, biological and grain yields, harvest index were highest for seed priming with MLE or CaCI2 in DSR-AWD. Similarly, grain quality, estimated in terms of normal grains, abortive and chalky grains, was also the highest in DSR-AWD with MLE osmo-priming. Benefit cost ratio and water productivity was also the highest in DSR-AWD for seed priming with MLE. In conclusion, seed priming with MLE or CaCI2 can be successfully employed to improve the direct seeded rice performance when practiced with alternate wetting and drying irrigation.
基金supported by the earmarked fund of China Agriculture Research System(CARS-22)the Key R&D Projects in Hunan Province,China(2017NK2051)+1 种基金the National Key R&D Program of China(2017YFD0301504 and 2018YFD03006)the Hunan Agricultural Science and Technology Innovation Fund Project,China(2018zd06)。
文摘Improved utilization of rice(Oryza sativa L.)straw and Chinese milk vetch(Astragalus sinicus L.,vetch)has positive effects on rice production.So far,few studies have investigated the productivity of vetch under different residue management practices in double-rice cropping system.The effects of rice straw on the growth and nutrient accumulation of vetch across seven years(2011–2017)and the subsequent effects of rice straw and vetch on two succeeding rice crops in a vetch–rice–rice cropping system,with the vetch established by relay cropping,were examined.The seven-year double-rice experiment consisted of the following treatments:(1)100%chemical fertilizer(F-F100);(2)only vetch without chemical fertilizer(M-Con);(3)80%chemical fertilizer plus vetch plus a low-cutting height(low-retained stubble)with the removal of straw(M-F80);(4)80%chemical fertilizer plus vetch plus a low-cutting height with the retention of straw(M-F80-LR);(5)80%chemical fertilizer plus vetch plus a high-cutting height(high-retained stubble)with the retention of straw(M-F80-HR);and(6)no fertilizer(F-Con).The yields of the two rice crops after vetch were not affected by either the cutting height of stubble with retention of straw or by the management of straw(retention vs.removal)with low-cutting height of stubble.The yields of the two rice crops after vetch were significantly higher for M-F80-HR than for M-F80-LR,but the relative contributions of the high-cutting height and straw retention to the higher rice yield could not be determined in this study.The yield stability of the double-rice grain in M-F80-HR was also increased,as determined by a sustainable yield index.Significant increases in vetch biomass and nutrient uptake were observed in the fertilized treatments during the rice season compared with the unfertilized treatments.In M-F80-HR plots,improvements in the growing environment of the vetch by conserving soil water content were associated with the highest vetch biomass,nutrient uptake,and yield stability of vetch biomass.These increased nutrient inputs partially replaced the demand for chemical fertilizer and stimulated the rice yields.It can be concluded that retaining higher-cutting stubble residues with straw retention could be the best straw management practice for increasing the vetch biomass and nutrient use efficiency,thereby allowing utilization of high-cutting height with retention of straw and vetch to improve the stability of rice productivity in a double-rice cropping system.
基金financially supported by the Agro-scientific Research in the Public Interest of China (201503122)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences (CAAS-XTCX2016008)
文摘The contribution percentage of inherent soil productivity(CPISP)refers to the ratio of crop yields under no-fertilization versus under conventional fertilization with the same field management.CPISP is a comprehensive measure of soil fertility.This study used 1086 on-farm trials(from 1984-2013)and 27 long-term field experiments(from 1979-2013)to quantify changes in CPISP.Here,we present CPISP3 values,which reflect the CPISP states during the first three years after site establishment,for a series of sites at different locations in China collected in 1984-1990(the 1980s),1996-2000(the 1990s),and 2004-2013(the 2000s).The results showed that the average CPISP3 value for three crops(wheat,rice,and maize)was 53.8%.Historically,the CPISP3 in the 1990s(57.5%)was much higher than those in the 1980s(50.3%),and the 2000s(52.0%)(P≤0.05).Long-term no-fertilization caused CPISP levels to gradually decline and then stabilize;for example,in a mono-cropping system with irrigation,the CPISP values in Northwest and Northeast China declined by 4.5 and 4.0%,respectively,each year for the first ten years,but subsequently,the CPISP values stabilized.In contrast,the CPISP for upland crops in double-cropping systems continued to decrease at a rate of 1.1%per year.The CPISP for upland-paddy cropping decreased very slowly(0.07%per year),whereas the CPISP for paddy cropping decreased sharply(3.1%per year,on average)for the first two years and then remained steady during the following years.Therefore,upland crops in double-cropping systems consume the most inherent soil productivity,whereas paddy fields are favourable for maintaining a high level of CPISP.Overall,our results demonstrate a need to further improve China’s CPISP3 values to meet growing productivity demands.
基金financially supported by the Key Project of the Chinese Academy of Sciences[grant number KZZD-EW-08]the consulting project"Strategy Study on the Ecological Function and Food Security Maintenance of Grassland in China"of the Chinese Academy of Engineeringsupported by the "Strategy and Policies on Environment and Development in Western China" project of "China Council for International Cooperation on Environment and Development(CCICED)."
文摘For making rational and scientific land-use planning,an inventory indicator of land productivity subject to biophysical limitations and human disturbance is required.This study introduces agricultural land productivity(ALP)as the dynamic indicator to measure land productivity,involving factors that affect agricultural production,such as characteristics of climate,soil,and terrain.As a case study of this dynamic indicator,ALP was estimated at county level and aggregated into provincial level in the whole of China.The result shows that ALP increased during 2000-2010 in China,and the ratios of ALP to the actual grain yield were 65.40%and 66.38%in the years 2000 and 2005,respectively.The ALP is an effective dynamic indicator to estimate the land productivity and to represent the basic conditions about the supply of water,energy,nutrients,and the physical basis for plant growth,as well as the local input.ALP estimation could provide supporting information for policy-making about land production planning and land-use management.
文摘Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria L.and Tecomella undulata L.and yields of Vigna radiata(L) in agroforestry systems in degraded lands of Indian Desert.Potential competition for resource between the trees and associated crop was analyzed by measuring soil water contents, soil organic matters and NH4-N at different depths of soil layers i.e., 0-25 cm, 25-50 cm and 50-75 cm in the experimental plots.The plots size were 16 m × 18 m(D1), 20 m × 18 m(D2) and 32 m × 18 m(D3) with tree densities of 208, 138 and 104 trees·ha-1 after June 2002, respectively.Results showed that tree height increased by 3% to 7% during June 2002 to June 2004.Collar diameter increased by 30% and 11% in D1, 23% and 19% in D2 and 18% and 36% in D3 plots, respectively, in P.cineraria and T.undulata in two years period.The increase in crown diameter was 9% to 18% in P.cineraria and 11% to 16% in T.undulata.Tree growth was relatively greater in 2002 than in 2003.Yield of V.radiata increased linearly from D1 to D3 plots.Lowest soil water content at 1 m distance from tree base indicated greater utilization of soil water within the tree rooting zone.Concentrations of soil organic matters and NH4-N were the highest(p<0.05) in 0-25 cm soil layer.P.cineraria was more beneficial than T.undulata in improving soil conditions and increasing crop yield by 11.1% and thus more suitable for its integration in agricultural land.The yield of agricultural crop increased when density of tree species was appropriate(i.e., optimum tree density), though it varied with tree size and depended upon resource availability.The result indicated bio-economic benefits of optimum density of P.cineraria and T.undulata over traditional practices of maintaining random trees in farming system in arid zones.
基金the project ‘Resource Conservation Technologies for Sustainable Development of Agriculture’
文摘In recent years, conventional rice production technologies have been leading to deterioration of soil health and declining farm profitability due to high inputs of water and labor. Conservation agriculture (CA) based resource-conserving technologies i.e. zero-tillage (ZT), raised-bed planting and direct-seeded rice (DSR) have shown promise as alternatives to conventional production technologies to overcome these problems. Present study was undertaken during 2009-2012 to establish an understanding of how permanent raised bed cropping system could be practiced to save water at the field application level to improve water productivity and also have the capability to enhance productivity, profitability and soil physical quality. The results showed that among different crop establishment techniques, conventional-tilled puddle transplanted rice (CT-TPR) required 14%-25% more water than other techniques. Compared with the CT-TPR system, zero till direct-seeded rice (ZT-DSR) consumed 6%-10%less water with almost equal system productivity and demonstrated higher water productivity. Wide raised beds saved about 15%-24% water and grain yield decrease of about 8%. Direct-seeded rice after ZT or reduced tillage or on unpuddled soil provided more net income than CT-TPR. The CT-TPR system had higher bulk density and penetration resistance due to compaction caused by the repeated wet tillage in rice. The steady-state infiltration rate and soil aggregation (〉 0.25 mm) were higher under permanent beds and ZT and lower in the CT-TPR system. Under CT-TPR, soil aggregation was static across seasons, whereas it improved under no-till and permanent beds. Similarly, mean weight diameter of aggregates was higher under ZT and permanent beds and increased over time. The study reveals that to sustain the rice productivity, CA-based planting techniques can be more viable options. However, the long-term effects of these alternative technologies need to be studied under varying agro-ecologies in western Uttar Pradesh, India.
文摘Potato productivity in the northeastern US has been relatively constant for over 50 years, raising questions about what factors are limiting productivity. Research was initiated in 2004 to identify key constraints to potato productivity by evaluating Status Quo (SQ), Soil Conserving (SC), and Soil Improving (SI) cropping systems under both rainfed and irrigated management, and it was found that addition of compost or irrigation substantially increased yield. In this study, we employed partial budgeting to determine cost differences and their impact on net revenue for these cropping systems. Differences in systems were primarily associated with rotation length, tillage operations, compost and application expenses, and water management practices. When compost (as composted dairy manure) was annually applied at 19 Mg haf-1 and evaluated over the entire 3-year crop rotation cycle, the compost-amended rainfed SI system was more expensive to maintain than the irrigated SC system if compost cost exceeded $3.63 Mg-1. Average marketable yields were used to calculate gross and net revenue for each system. Because average potato yield for the irrigated SQ system (28.4 Mg·ha-1) equaled that in the rainfed SI system (28.3 Mg·ha-1), we were able to compare cost of irrigation versus compost for achieving comparable yield. The compost-amended SI system under rainfed management generated more net revenue from the potato crop than the irrigated SQ system when compost costs were less than $7.42 Mg-1. When compared to the commonly used rainfed SQ system, rainfed SI achieved higher net revenue as long as compost cost was less than $22.95 Mg-1. The rainfed SI system achieved higher net revenue than the irrigated SC system when compost cost was $9.43 Mg-1or less, but generated greater net revenue than the rainfed SC system regardless of compost costs, due to substantially higher yields associated with compost amendment. This investigation demonstrates that compost is a potentially viable substitute to irrigation for potato in the northeastern US;however, such potential is highly dependent on suitable compost sources and application costs.
基金Under the auspices of Scientific and Technological Development Program of Jilin Province(No.20220101154JC)Strategic Pioneering Science and Technology Special Project of Chinese Academy of Sciences(No.XDA28080503)+1 种基金National Natural Science Foundation of China(No.42071025)Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2023240)。
文摘Building a more resilient response system to climate change for sustainable development and reducing uncertainty in China’s food markets,requires access to historical research gaps and mapping future research progress for decision making.However,the lack of quantitative and objective analyses to ensure the stability and development of agroecosystems increases the complexity of agro-climatic mechanisms,which leads to uncertainty and undesirable consequences.In this paper,we review the characteristics of climate change in China(1951–2020),reveal the mechanisms of agroecosystem structure in response to climate,and identify challenges and opportunities for future efforts in the context of research progress.The aim is to improve the scientific validity and relevance of future research by clarifying agro-climatic response mechanisms.The results show that surface temperature,precipitation,and frequency of extreme weather events have increased to varying degrees in major agricultural regions of China in 1951–2020.And they have strong geographic variation,which has resulted in droughts in the north and floods in the south.Moreover,climate change has complicated the mechanisms of soil moisture,Net Primary Productivity(NPP),soil carbon pool,and crop pest structure in agroecosystems.This lends to a reduction in soil water holding capacity,NPP,soil carbon content,and the number of natural enemies of diseases and insects,which in turn affects crop yields.However,human interventions can mitigate the deterioration of these factors.We have also realized that the methodology and theory of historical research poses a great challenge to future agroecosystem.Historical and projected climate trends identified current gaps in interdisciplinary integration and multidisciplinary research required to manage diverse spatio-temporal climate change impacts on agroecosystems.Future efforts should highlight integrated management and decision making,multidisciplinary big data coupling,and numerical simulations to ensure sustainable agricultural development,ecological security,and food security in China.
基金This study was supported by Gansu Provincial Key Laboratory of Aridland Crop Science of Gansu Agricultural University(GSCS-2020-Z6)the China Agriculture Research System of Construct Special(CARS-14-1-16)+1 种基金the National Natural Science Programs of China(31660368,32060437)the Fuxi Outstanding Talent Cultivation Plan of Gansu Agriculture University(Gaufx-02J05).I am very grateful to all my working partners.
文摘To investigate the effects of crop rotation on oilseed flax growth and yield,three season experiments were carried out in semi-arid area of Dingxi,Gansu from 2017 to 2019.The designed 6 rotational systems were FFF(flax-flaxflax),PFF(potato-flax-flax),WPF(wheat-potato-flax),FPF(flax-potato-flax),PWF(potato-wheat-flax)and FWF(flax-wheat-flax).Flax growth and yield investigation results showed that crop rotation increased leaf area duration,dry matter accumulation,seed nitrogen accumulation,water and nitrogen used efficiency,compared with continuous cropping of flax.Flaxseed yields in rotation systems were 22.23%–44.11%greater than those of continuous cropping system.Those in wheat and potato stubbles had higher tiller number(21.43%and 29.46%),more branches(14.24%and 6.97%),effective capsules(26.35%and 28.79%),higher water use efficiency(40.26%and 33.5%),higher nitrogen partial factor productivity(33.85%and 31.46%)and dry matter(41.98%and 25.47%)than those in oilseed flax stubble.It concluded that crop rotation system was an effective measure for oilseed flax productivity in semi-arid area by improving yield components and promoting biomass.