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1.
Agricultural chemical use has caused a public concern over environmental issue while decisions about applying chemicals are made by individual farmers. The critical decision-making role of farmers relative to agricultural chemical use creates a need for accurate information on their perceptions of various chemical-related hazards and the factors that may influence such judgments. Based on data collected from 177 land operators at Xinxiang County in Henan Province of China, an empirical analysis is conducted to examine the relationship between farmers' character and the behavior of fertilizer application. Study findings reveal that: the characteristics of household head and household, and the nature of farming management positively affect the amount of fertilizers applied; information on fertilizers and the knowledge about environmental impact of fertilizer application have negative impacts by contrast. To formulate effective pollution control policies at the farm level, it is imperative for policy-makers to convey information to producers by demonstration projects, technical assistance, and education programs. Under a changed political environment, some combination of education and economic incentives could be lower cost and more effective tools for achieving desired environmental conservative goals.  相似文献   

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Problems associated with land degradation are serious in China. Sloping land in South China has experienced a decline in crop productivity by 30-60% due to soil erosion and it has been predicted that most topsoil will be lost within the next 100 years if current erosion rates continue. Considering these situations, an agro-environmental research and development project (Sustainable Highland Agriculture in South-East Asia- SHASEA) was conducted in a catchment in Yunnan Province, China, to address the objectives of increasing crop productivity in sustainable and environmentally-friendly ways. A range of cropping practices was developed and implemented in a rural upland catchment (Wang Jia). At the end of the project, farmers were surveyed to evaluate project effectiveness. All farmers from Wang Jia Catchment, who were involved in project implementation, were surveyed. A sample of farmers working in an adjacent catchment (not associated with the project) was surveyed for comparative purposes. Farmers had different perceptions of the cropping practices employed. Contour cultivation was preferred and likely to be adopted. Others practices such as straw mulching and intercropping were seen as less appropriate and unlikely to be adopted. Polythene mulch was recognized as effective, but likely to be adopted only if financial returns were favourable. The availability of relevant information had an important impact on the extent of technology testing by farmers and their willingness to adopt the practices in the future.  相似文献   

4.
The livelihoods of farmers are responding to the mioroeconomic policies and result in many changes in the landuse pattern and landscape, and the farmer's attitude to the natural resources conservation, specifically in the land degradation. In order to find the relationship between the farmers' response to the microeeonomic policies and land degradation, the authors surveyed 120 household in three villages in the black soil zone in Heilongjiang Province. Based on the feedback of the questionnaires, the authors established a model to analyze the impact. The results demonstrated that land degradation was impacted by farmers behaviors in the process of the adjustment of agricultural structures in the city of Zhaodong. And the main factors acted on the land degradation were the agricultural labour education level, the transfer of the labour from agricultural production, the price of the agricultural production materials, and the land scale management. The authors put forward some suggestions for sustainable agriculture based on the analysis on the topic.  相似文献   

5.
Proper application of nitrogen(N) fertilizers and irrigation management are important production practices that can reduce nitrate leaching into groundwater and improve the N use efficiency(NUE). A lysimeter/rain shelter facility was used to study effects of the rate of N fertilization, type of N fertilizer, and irrigation level on key aspects of winter wheat production over three growing seasons(response variables were nitrate transport, N leaching, and NUE). Results indicated that nitrate concentration in the soil profile and N leaching increased with the rate of N fertilization. At the end of the third season, nitrate concentration in the top 0–75 cm layer of soil was higher with manure treatment while urea treatments resulted in higher concentrations in the 100–200 cm layer. With normal irrigation, 3.4 to 15.3% of N from applied fertilizer was leached from the soil, yet no leaching occurred under a stress irrigation treatment. The manure treatment experienced less N leaching than the urea treatment in all cases except for the 180 kg N ha-1 rate in 2011–2012(season 3). In terms of grain yield(GY), dry matter(DM) or NUE parameters, values for the manure treatment were lower than for the urea treatment in 2009–2010(season 1), yet were otherwise higher for urea treatment in season 3. GY and crop nitrogen uptake(NU) were elevated when the rate of N fertilizer increased, while the NUE decreased; GY, DM, and NU increased with the amount of irrigation. Data indicated that reduced rates of N fertilization combined with increased manure application and proper irrigation management can lower nitrate levels in the subsoil and reduce potential N leaching into groundwater.  相似文献   

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Zea mays var. saccharata (sweet corn) is an important crops grown for food and feed in the tropics. In Indonesia, most of the land used for crops production is characterized by acid pH and low levels of nitrogen and phosphorus. Phosphorus fertilizers have been widely used to improve soil fertility in Indonesia. Given the high cost of superphosphate (SP), the focus is now on rock phosphate (RP) fertilizer, which is relatively cheaper than SP and shows high solubility in acid condition. The combination of RP and manure during the decomposing process and the addition of decomposing microbes may be a promising technique to overcome the problem. A field experiment was conducted on a vertisol soil (low pH and low available nitrogen and phosphorus). The objective of the research is to evaluate the effect of combinations of manure enriched with RP (granular and non-granular) with three different decomposing microbes (EM4, starTmik and stardec) on sweet corn and dry matter production, phosphorus (P) and calcium (Ca) content in above-ground biomass. A completely randomized design with seven treatments and four replicates was used in this experiment. The size of the plots was 3 m x 2.5 m. The treatments were TO (manure), T1 (manure + EM4), T2 (manure + starTmik), T3 (manure + stardec), T4 (manure granular ~ EM4), T5 (manure granular + starTmik), T6 (manure granular + stardec). The manure was enriched with RP 66 kg P/ha (150 kg P2Os/ha) and inoculated with the biodecomposer according to the assigned treatment. The manure was applied in a rate of 30 t/ha. All plot received 125 kg KC1/ha (150 kg K20/ha) and 200 kg urea/ha as basal fertilization. Sweet corn was harvested 70 d after planting. Sweet corn plants were cut close to the ground and analyzed for dry matter yield (DM) and P and Ca content in the biomass. Result showed that sweet corn and DM yield and P content were not significantly influenced by the treatments. Ca content in the above-gro  相似文献   

8.
The livelihoods of farmers are responding to the microeconomic policies and result in many changes in the landuse pattern and landscape, and the farmer's attitude to the natural resources conservation, specifically in the land degradation. In order to find the relationship between the farmers' response to the microeconomic policies and land degradation, the authors surveyed 120 household in three villages in the black soil zone in Heilongjiang Province. Based on the feedback of the questionnaires, the authors established a model to analyze the impact. The results demonstrated that land degradation was impacted by farmers behaviors in the process of the adjustment of agricultural structures in the city of Zhaodong. And the main factors acted on the land degradation were the agricultural labour education level, the transfer of the labour from agricultural production, the price of the agricultural production materials, and the land scale management. The authors put forward some suggestions for sustainable agriculture based on the analysis on the topic.  相似文献   

9.
Nitrogen(N) is one of the macronutrients required for plant growth, and reasonable application of N fertilizers can increase crop yields and improve their quality. However, excessive application of N fertilizers will decrease N use efficiency and also lead to increases in N2 O emissions from agricultural soils and many other environmental issues. Research on the effects of different N fertilizer management practices on wheat yields and N2 O emissions will assist the selection of effective N management measures which enable achieving high wheat yields while reducing N2 O emissions. To investigate the effects of different N management practices on wheat yields and soil N2 O emissions, we conducted field trials with 5 treatments of no N fertilizer(CK), farmers common N rate(AN), optimal N rate(ON), 20% reduction in optimal rate+dicyandiamide(ON80%+DCD), 20% reduction in optimal rate+nano-carbon(ON80%+NC). The static closed chamber gas chromatography method was used to monitor N2 O emissions during the wheat growing season. The results showed that there were obvious seasonal characteristics of N2 O emissions under each treatment and N2 O emissions were mainly concentrated in the sowing-greening stage, accounting for 54.6–68.2% of the overall emissions. Compared with AN, N2 O emissions were decreased by 23.1, 45.4 and 33.7%, respectively, under ON, ON80%+DCD and ON80%+NC, and emission factors were declined by 22.2, 66.7 and 33.3%, respectively. Wheat yield was increased significantly under ON80%+DCD and ON80%+NC by 12.3 and 11.9%, respectively, relative to AN while there was no significant change in yield in the ON treatment. Compared with ON, overall N2 O emissions were decreased by 29.1 and 13.9% while wheat yields improved by 18.3 and 17.9% under ON80%+DCD and ON80%+NC, respectively. We therefore recommend that ON80%+DCD and ON80%+NC be referred as effective N management practices increasing yields while mitigating emissions.  相似文献   

10.
The purpose of this study was to indentify the most important determinants associated with behavior change by comparing the influence of intervening variables and the characteristics of the farmer and the farm (independent variables) on the adoption behavior of farmers for recommended agronomic practices. A total of 107 farmers out of a population of 214 were randomly selected from two adjoining districts of South Africa and Lesotho. Chi-square and correlations and regression analyses were used to determine the relationship between the independent, dependent and intervening variables. The results show clear differences between the independent in regard to their influence on adoption behavior, but these influences also vary significantly between the practices. In general the influence of independent variable is limited, and together their total contribution in explaining the variance in adoption (R2) varied between about 20 to 40 percent whilst that of the intervening variables varied between 50 and over 70 percent, which clearly supports the research hypothesis that their prediction arid explanation value in terms of behavior is much bigger than that of independent, personal and environmental factors.  相似文献   

11.
This paper reviewed rainwater collection and water resource management in Ningnan County in southwestern mountain of China,as a case study for solving the problems of water management in a simple and sustainable way. In this mountainous agriculture system,private agricultural enterprises were introduced into local mountain agriculture to solve capital fund shortage for the construction of rainwater harvesting system. Agreement was signed by private agriculture enterprises with the target farmers to subscribe for the household agriculture production at a protection price. Cash invested by the enterprise and subsidy from the government were collected for purchasing materials,while the farmers supplied labors for the construction of water harvesting systems. The system solved the share of input and benefits between the local government,enterprise and household farms successfully. In addition,the micro water harvesting tanks and micro irrigate systems extend quickly in this mountainous county. Up to 2007,more than 12 000 rainwater harvesting tanks had been established and more than 8.5×104 hm2 dry arable land accounting for nearly 75% of the total arable land had been irrigated efficiently. Per capita income of farmer had been increased by 14 times in the past 20 years. Considerable potential for further improvement in implementation of the models for solving water shortage and water resource management in mountain region maybe depend on more local private agriculture enterprises and households than the government.  相似文献   

12.
《农业科学学报》2019,18(8):1667-1679
With an increasing population and changing diet structure, summer maize is increasingly becoming an important energy crop in China. However, traditional farmer practices for maize production are inefficient and unsustainable. To ensure food security and sustainable development of summer maize production in China, an improved, more sustainable farmer management system is needed. Establishing this system requires a comprehensive understanding of the limitations of current farming practice and the ways it could be improved. In our study, 235 plots from three villages in the North China Plain(NCP) were monitored. Maize production on farms was evaluated; our results showed that the maize yield and nitrogen partial factor productivity(PFP_N) were variable on smallholder farms at 6.6~(–1)3.7 t ha~(–1) and 15.4–88.7 kg kg~(–1), respectively.Traditional farming practices also have a large environmental impact(nitrogen surplus: –64.2–323.78 kg ha~(–1)). Key yield components were identified by agronomic diagnosis. Grain yield depend heavily on grain numbers per hectare rather than on the 1 000-grain weight. A set of improved management practices(IP) for maize production was designed by employing a boundary line(BL) approach and tested on farms. Results showed that the IP could increase yield by 18.4% and PFP_N by 31.1%, compared with traditional farmer practices(FP), and reduce the nitrogen(N) surplus by 57.9 kg ha~(–1). However,in terms of IP effect, there was a large heterogeneity among different smallholder farmers' fields, meaning that, precise technologies were needed in different sites especially for N fertilizer management. Our results are valuable for policymakers and smallholder farmers for meeting the objectives of green development in agricultural production.  相似文献   

13.
Careful soil management is important for the soil quality and productivity improvement of the reclaimed coastal tidal flat saline land in northern Jiangsu Province, China. Farmyard manure( FYM) and mulch applications, which affect soil characteristics and plant significantly, are regard as an effective pattern of saline land improvement. As a conventional management in the study region, FYM and mulch are used for the amendment of the new reclaimed tidal flat regularly, but little is known about their effects on soil physical properties functioning. A study was conducted on a typical coastal tidal flat saline land, which was reclaimed in 2005, to evaluate the effects of FYM, polyethylene film mulch(PM), straw mulch(SM), FYM combined with PM(FYM+PM), FYM combined with SM(FYM+SM), on soil hydraulic properties and soil mechanical impedance. CK represented conventional cultivation in study area without FYM and mulch application and served as a control. The experiment, laid out in a randomized complete block design with three replications, was studied in Huanghaiyuan Farm, which specialized in the agricultural utilization for coastal tidal flat. Result showed that capillary water holding capacity(CHC), saturated water content(SWC), saturated hydraulic conductivity( Ks) and bulk density(BD), cone index(CI) were affected significantly by the FYM and mulch application, especially in the 0-10 cm soil layer. FYM and mulch management increased CHC, SWC and Ks over all soil depth in the order of FYM+SM〉FYM+PM〉FYM〉SM〉PM〉CK. With the contrary sequence, BD and CI decreased significantly; however, FYM and mulch application affected BD and CI only in the upper soil layers. CHC, SWC and Ks decreased significantly with the increasing of soil depth, BD and CI, and a significant liner equation was found between CHC, SWC, Ks and BD, CI. With the highest CHC(38.15%), SWC(39.55%), Ks(6.00 mm h-1) and the lowest BD(1.26 g cm-3) and CI(2.71 MPa), the combined man  相似文献   

14.
To feed the increasing world population, more food needs to be produced from agricultural land systems. Solutions to produce more food with fewer resources while minimizing adverse environmental and ecological consequences require sustainable agricultural land use practices as supplementary to advanced biotechnology and agronomy. This review paper, from a land system perspective, systematically proposed and analyzed three interactive strategies that could possibly raise future food production under global change. By reviewing the current literatures, we suggest that cropland expansion is less possible amid iferce land competition, and it is likely to do less in increasing food production. Moreover, properly allocating crops in space and time is a practical way to ensure food production. Climate change, dietary shifts, and other socio-economic drivers, which would shape the demand and supply side of food systems, should be taken into consideration during the decision-making on rational land management in respect of sustainable crop choice and allocation. And ifnally, crop-speciifc agricultural intensiifcation would play a bigger role in raising future food production either by increasing the yield per unit area of individual crops or by increasing the number of crops sown on a particular area of land. Yet, only when it is done sustainably is this a much more effective strategy to maximize food production by closing yield and harvest gaps.  相似文献   

15.
Tillage practices and organic amendment are strategies used worldwide to preserve the properties and fertility of soils.This study aimed to elucidate effects of 3-year field treatments of tillage practice and straw management on physical properties of Mollisols, root architecture and maize yield in northeast China. The experiment was conducted from 2015 to 2018 following a splitplot design of a randomized complete block with tillage practices [rotary tillage(R) and deep tillage(D)] as main plots...  相似文献   

16.
Spring maize is one of the most popular crops planted in northeastem China. The cropping systems involving spring maize have been maintaining high production through intensive management practices. However, the high rates of nitrogen (N) fertilizers application could have introduced a great amount of nitrous oxide (N2O) into the atmosphere. It is crucial for sustaining the maize production systems to reduce N2O emissions meanwhile maintaining the optimum yields by adopting alternative farming management practices. The goal of this study was to evaluate effects of alternative fertilization and crop residue management practices on N2O emission as well as crop yield for a typical maize field in northeastern China. Field experiments were conducted during the 2010-2011 maize growing seasons (from early May to late September) in Liaoning Province, northeastern China. N2O fluxes were measured at the field plots with six different treatments including no N fertilizer use (CK), farmers' conventional N fertilizer application rate (FP), reduced N fertilizer rate (OPT), reduced N fertilizer rate combined with crop straw amendment (OPTS), slow-release N fertilizer (CRF), and reduced N fertilizer rate combined with nitrification inhibitor (OPT+DCD). The static chamber method combined with gas chromatography technique was employed to conduct the measurements of N2O fluxes. The field data showed that N2O emissions varied across the treatments. During the maize growing season in 2010, the total N2O emissions under the treatments of CK, FP, OPT, OPTS, and CRF were 0.63, 1.11, 1.03, 1.26, and 0.98 kg N ha-1, respectively. The seasonal cumulative N2O emissions were 0.54, 1.07, 0.96, 1.12, and 0.84 kg N ha1, respectively, under CK, FP, OPT, OPTS, and OPT+DCD in 2011. In comparison with FP, CRF or OPT+DCD reduced the N2O emissions by 12 or 21%, respectively, while the crop yields remained unchanged. The results indicate that the reduction of N-fertilizer application rate in combination with the slow-release fertilizer type or nitrification inhibitor could effectively mitigate N2O emissions from the tested field. The incorporation of crop residue didn't show positive effect on mitigating N2O emissions from the tested cropping system. The field study can provide useful information for the on-going debate on alternative N fertilization strategies and crop straw management in China. However, further studies would be needed to explore the long-term impacts of the alternative management practices on a wide range of environmental services.  相似文献   

17.
Biochar is considered as a beneficial soil amendment for crop production. However, limited information is available on the effects of continuous applications of biochar on rice. In this study, a fixed field experiment was conducted in the early and late rice-growing seasons from 2015 to 2017. Grain yield and yield attributes with a widely-grown rice cultivar Zhongzao 39 were compared, with and without applications of biochar in each season. The results showed that grain yield initially decreased with biochar applications in the first three seasons due to decreases in grain weight and harvest index. Although there were further relative decreases in grain weight and harvest index for rice that was supplied with biochar in the fourth to sixth seasons, grain yield was increased(by 4–10%) because of increases in sink size(spikelets per m2) and total biomass. The increased sink size in rice whose soil had been supplied with biochar in the fourth to sixth seasons was achieved by increasing panicle size(spikelets per panicle) or number of panicles, or both. Our study suggests that the positive effects of biochar application on rice yield and yield attributes depend on the duration of biochar application. Further investigations are needed to determine what are the soil and physiological processes for producing yield responses associated with ongoing applications of biochar. Also, it should be evaluated the performance of biochar application combined with other management practices, especially those can increase the grain weight and harvest index in rice production.  相似文献   

18.
Field experiment was carded out to nitrogen release characteristics of rice controlled release fertilizer (RCRF) coated with natural and half natural high molecular materials, and to thereof effects on the nitrogen uptake and yield of early and late hybrid rice from 1999 to 2000, with urea as control.In experimental fields regardless of early and late seasons, the amount of N in the plants increased exponentially at the early growth stage (y=ab^x) and nonlinearly at the middle and late growth stages(y=a bx cx^2).Rice controlled release fertilizer lengthened the exponential phase and increased the parameter -b/c during the nonlinear phase. Although the N amount of plants was less in rice controlled release fertilizer plots than in urea plots within 20 days after transplanting, at the heading and maturity stages, the N amount of plants in rice controlled release fertilizer plots was above two times greater than in the urea plots due to the higher N recovery, and the high absorption density of N in the nonlinear phase. Tillers pattern and achievement of the maximum filleting stage varied with fertilizer types. The maximum tillering stage in the urea plots occurred a week earlier than in the rice controlled release fertilizer plots. Yield sink size and potential sink size of the plants reflected the N absorption pattern and the amount of N in the plants. The yields of early and late rice with 90 kg N ha^-1 of rice controlled release fertilizer were respectively increased by 832.7 kg ha-1 and 412.8 kg ha-1 than those with 90 kg N ha^-1 of urea, almost equivalent to the yield of early and late hybrid rice with 180 kg N ha^-1 of urea.  相似文献   

19.
Monitoring and assessment of agricultural land degradation is of vital importance for better land and water management planning and reclamation. It requires setting baseline information and basic analysis at specific time and space. About 33 geo-referenced soil sampling spots were selected in two agricultural production locations in the Kingdom of Bahrain to assess the status and preliminary causes of land degradation. Soil samples were taken from 13 sites in Diraz location while 19 samples were taken from Budayyi location. The samples were taken to 90 cm depth at 30 cm intervals. Standard procedures were followed to determine soil physiochemical properties. In addition, field observations on farm condition, distance from the sea, method of irrigation and irrigation water source were taken. Some of the soil samples were deliberately taken from outside the irrigated basins among trees compared with samples taken from inside the actively growing area for comparison. The results indicated that the salinity level was significantly (P 〈 0.001) higher at the 0-30 cm soil depth compared with 30-60 cm or 60-90 cm depths in both locations. The distance from the sea did not show clear correlation with surface soil salinity in Budayyi area compared with Diraz. Both locations showed significantly higher salinity levels on samples taken outside the actively growing areas compared with those taken from within. The effect is more prominent at the 0-30 cm depth. The observed variability on salinity levels may be attributed to farm management practices and deteriorating quality of ground water. Thus, agricultural land degradation in Bahrain cannot be attributed to ground water deterioration alone. The use of tertiary treated sewage water (TSE) may ease the pressure on ground water, but the pH of the TSE should be carefully monitored and managed with proper studies on leaching requirements to avoid further salinity complications.  相似文献   

20.
Ground cover management and farmyard manure(FYM) management have important roles in organic lettuce production.However,there is not enough information about their combined effects.In order to assess the effects of individual and combined ground cover and FYM management on soil mineral N(NH_4-N and NO_3-N) dynamics,lettuce yield and economics in organic farming,a two-year field experiment was conducted on a certified organic farm in Kisac(Vojvodina,Serbia).The experiment had a two-factorial split-plot completely randomized block design.FYM was applied on the half of the experimental field as a whole-plot factor,while ground cover management included the following four treatments:(Ⅰ)control,without ground cover management(φ);(Ⅱ) hoeing(H);(Ⅲ) agrotextile cover;(Ⅳ) straw mulch(SM),which were applied on split plots.The applied SM and AT increased soil moisture by 12.83 and 3.73%,respectively,compared to the control treatment.FYM increased soil mineral N concentration,the lettuce fresh matter(FM) yield and nitrate concentration in lettuce.However,nitrate concentration in lettuce in all treatments was below the limit required by the European Commission(EC)(2001).The highest lettuce yield was obtained by AT(39122 kg),followed by SM(33 925 kg),and it was higher with FYM application by 16.85%.Hoeing did not positively affect the yield,probably due to its negative effect on soil moisture.Additional profit was higher with FYM,showing the following decreasing order:ATHSM0.However,value/cost ratio(VCR) was in the order(?)HSMAT on FYM fertilized plots.FYM application led to higher lettuce yield and higher profit and VCR.In case a farm does not have FYM,SM is the best alternative due to its positive effect on the yield and low investment costs.  相似文献   

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