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1.
Geo-referenced information on crop production that is both spatially- and temporally-dense would be useful for management
in precision agriculture (PA). Crop yield monitors provide spatially but not temporally dense information. Crop growth simulation
modelling can provide temporal density, but traditionally fail on the spatial issue. The research described was motivated
by the challenge of satisfying both the spatial and temporal data needs of PA. The methods presented depart from current crop
modelling within PA by introducing meta-modelling in combination with inverse modelling to estimate site-specific soil properties.
The soil properties are used to predict spatially- and temporally-dense crop yields. An inverse meta-model was derived from
the agricultural production simulator (APSIM) using neural networks to estimate soil available water capacity (AWC) from available
yield data. Maps of AWC with a resolution of 10 m were produced across a dryland grain farm in Australia. For certain years
and fields, the estimates were useful for yield prediction with APSIM and multiple regression, whereas for others the results
were disappointing. The estimates contain ‘implicit information’ about climate interactions with soil, crop and landscape
that needs to be identified. Improvement of the meta-model with more AWC scenarios, more years of yield data, inclusion of
additional variables and accounting for uncertainty are discussed. We concluded that it is worthwhile to pursue this approach
as an efficient way of extracting soil physical information that exists within crop yield maps to create spatially- and temporally-dense
datasets. 相似文献
2.
Kishor Atreya 《Agriculture and Human Values》2007,24(3):399-409
The concept of community integrated pest management (IPM), which is well developed in Indonesia and Vietnam, was recently
introduced in Nepal. However, it has not been widely practiced, due mainly to lack of financial and technical support. This
study determined an individual’s willingness to pay (WTP) for community IPM training. Determinants of WTP were identified;
and sample average estimates, opportunity costs of training, and probability values were used to estimate WTP for a group
of households. Estimated WTP revealed that individuals were in favor of community IPM, hence it could be implemented with
the support of local villagers. Community IPM demand functions showed that individuals’ knowledge and awareness of pesticide
pollution are crucial for implementation. The annual welfare gained by providing five days community IPM training was calculated
to be US $25.23 per household.
Kishor
Atreya
has a Master’s degree in Environmental Science and is currently working at Alternative Development and Research Center (ADRC)
as Research Director. ADRC – Nepal is a national non-governmental organization dedicated to interdisciplinary research for
alternative development. His research interests are in development of agri-environmental indicators, land and water quality,
land use change and degradation, agricultural intensification and environment, and economic valuation of environmental pollution. 相似文献
3.
Delineating productivity zones in a citrus grove using citrus production,tree growth and temporally stable soil data 总被引：1，自引：0，他引：1
The productivity of a citrus grove with variation in tree growth was mapped to delineate zones of productivity based on several
indicator properties. These properties were fruit yield, ultrasonically measured tree canopy volume, normalized difference
vegetation index (NDVI), elevation and apparent electrical conductivity (ECa). The spatial patterns of soil series, soil color and ECa, and their correspondence with the variation in yield emphasized the importance of variation in the soil in differentiating
the productivity of the grove. Citrus fruit yield was positively correlated with canopy volume, NDVI and ECa, and yield was negatively correlated with elevation. Although all the properties were strongly correlated with yield and
were able to explain the productivity of the grove, citrus tree canopy volume was most strongly correlated (r = 0.85) with yield, explaining 73% of its variation. Tree canopy volume was used to classify the citrus grove into five productivity
zones termed as ‘very poor’, ‘poor’, ‘medium’, ‘good’ and ‘very good’ zones. The study showed that productivity of citrus
groves can be mapped using various attributes that directly or indirectly affect citrus production. The productivity zones
identified could be used successfully to plan soil sampling and characterize soil variation in new fields. 相似文献
4.
《东北农业大学学报(英文版)》2016,(4):82-92
There has been a steady growth in demand for convenience and ready-cooked food has influenced the interest of poultry processors in developing value-added chicken products that meet consumers' demand/choice. A conjoint analysis was done in this study on the survey of 975 chicken consumers in the Niger Delta Region of Nigeria, between March and September, 2014 to valuate consumers, preferences and willingness to pay (WTP) for various chicken attributed parts, production method, processing method, storage method, the presence of flavor and cooking method. The estimates of consumers, WTP premium prices for various mixtures of value-added characteristics were ascertained. The consumers preferred chicken products refrigerated, from chicken produced under free-range management, chicken breast, chicken product that was addictive and flavor free, which could be oven-heated or pan heated. One half of the entire respondents were willing to pay about 25% more for value-added chicken product over the price for conventional products. On the whole, a premium for value-added chicken products was more likely to be paid for by young consumers, consumers who patronized farmers' markets and preferred free-range or organic chicken products. WTP by consumers was negatively affected by price of products. The poultry industry could utilize combined knowledge of consumers' WTP for value-added chicken product price as a guide of develop innovative value-added chicken products. 相似文献
5.
Hugh Campbell 《Agriculture and Human Values》2009,26(4):309-319
Early food regimes literature tended to concentrate on the global scale analysis of implicitly negative trends in global food
relations. In recent years, early food regimes authors like Harriet Friedmann and Philip McMichael have begun to consider
the sites of resistance, difference and opportunity that have been emerging around, and into contestation with, new food regime
relations. This paper examines the emerging global-scale governance mechanism of environmental food auditing—particularly
those being promoted by supermarkets and other large food retailers—as an important new dynamic in our understanding of the
politics and potentials of food regimes. Commencing with an examination of Friedmann’s corporate environmental food regime,
two key dynamics are identified as being pivotal in the rise and decline of global-scale regimes: securing social legitimacy
for food relations and the importance of ecological dynamics in global food relations. By extending McMichael’s notion of
‘Food from Nowhere’ versus ‘Food from Somewhere’, the paper interrogates the emergence of a cluster of relations that comprise
‘Food from Somewhere’ and examines whether this cluster of relations has the potential to change some of the constituent ecological
dynamics of food regimes. These ecological dynamics have historically been problematic, amply demonstrating Marx’s metabolic
rift as the early food regimes solidified relationships between ‘ecologies at a distance’. By using socio-ecological resilience
theory, ‘Food from Somewhere’ is characterized as having denser ecological feedbacks and a more complex information flow in
comparison to the invisibility and distanciation characterizing earlier regimes as well as contemporary ‘Food from Nowhere’.
The conclusion of this article is that while ‘Food from Somewhere’ does provide one site of opportunity for changing some
key food relations and ecologies, the social legitimacy of this new form of food relations does rely on the ongoing existence
of the opposite, more regressive, pole of world food relations. The key question for resolving this tension appears to be
whether new food relations can open up spaces for future, more ecologically connected, global-scale food relations. 相似文献
6.
Lack of automatic weed detection tools has hampered the adoption of site-specific weed control in cereals. An initial object-oriented
algorithm for the automatic detection of broad-leaved weeds in cereals developed by SINTEF ICT (Oslo, Norway) was evaluated.
The algorithm (“WeedFinder”) estimates total density and cover of broad-leaved weed seedlings in cereal fields from near-ground red–green–blue images.
The ability of “WeedFinder” to predict ‘spray’/‘no spray’ decisions according to a previously suggested spray decision model for spring cereals was
tested with images from two wheat fields sown with the normal row spacing of the region, 0.125 m. Applying the decision model
as a simple look-up table, “WeedFinder” gave correct spray decisions in 65–85% of the test images. With discriminant analysis, corresponding mean rates were 84–90%.
Future versions of “WeedFinder” must be more accurate and accommodate weed species recognition. 相似文献
7.
2011／12年度全球棉花收获面积增长,产量再次超过2700万t。受经济恢复迟缓等影响,同期棉花消费不足2300万t。国际棉花市场供过于求,期末库存继续增加,库存消费比达到67．4％的历史高点。受全球棉花供求关系和中国棉花临时收储政策等因素影响,国际棉花价格持续下跌,国内棉价相对稳定,国内外价差拉大。全球棉花进出口贸易加大,中国棉花进口激增。展望2012／13年度,预计全球棉花植棉面积产量下降,消费状况有所好转,但仍产大于需,库存持续增加,在基本面不变的情况下,未来国际棉价仍将保持弱势震荡格局。 相似文献
8.
Bill Pritchard 《Agriculture and Human Values》2009,26(4):297-307
A benchmark question in contemporary food regimes scholarship is how to theorize agriculture’s incorporation into the WTO.
For the most part, it has been theorized as an institutional mechanism that facilitates the ushering in of a new, so-called
‘third food regime’, in which food–society relations are governed by the overarching politics of the market. The collapse
of the Doha Round negotiations in July 2008 makes it possible, for the first time, to offer a conclusive assessment as to
whether this is the case. Using a broadly conceived world-historical framework, this article contends that the WTO is more
appropriately theorized as a carryover from the politics of the crisis of the second food regime, rather than representing
any putative successor. The Doha Round’s collapse in Geneva in July 2008 should put an end to speculation of a WTO-led transformation
of global food politics towards unfettered market rule; the supposed basis for a neo-liberalized ‘third food regime’. Consequently,
it is through analysis of the factors that framed the Doha Round’s collapse, rather than in the WTO itself, that provide insights
into the defining elements of a new global politics of food. 相似文献
9.
十一五”时期我国棉花生产发展目标和对策 总被引：2，自引：0，他引：2
毛树春 《中国农业科技导报》2006,8(3):57-61
论述进入新世纪,我国棉花数量、质量和效益需求都跃上高台阶的新形势,围绕新任务,提出“十一五”棉花生产发展目标,扩大面积,提高单产和改善品质,转变经济增长方式,全力协调产量、质量和效益的同步发展;提出大力发展棉花科技,出台棉花保护政策和最低价,发展棉花保险业务,正确使用进口棉花的配额和关税等相关保障措施。 相似文献
10.
Kevin J. Sibley Tessema Astatkie Gordon Brewster Paul C. Struik John F. Adsett Kris Pruski 《Precision Agriculture》2009,10(2):162-174
One of the many gaps that needs to be solved by precision agriculture technologies is the availability of an economic, automated,
on-the-go mapping system that can be used to obtain intensive and accurate ‘real-time’ data on the levels of nitrate nitrogen
(NO3–N) in the soil. A soil nitrate mapping system (SNMS) has been developed to provide a way to collect such data. This study
was done to provide extensive field-scale validation testing of the system’s nitrate extraction and measurement sub-unit (NEMS)
in two crop (wheat and carrot) production systems. Field conditions included conventional tillage (CT) versus no tillage (NT),
inorganic versus organic fertilizer application, four soil groups and three points in time throughout the season. Detailed
data analysis showed that: (i) the level of agreement, as measured by root mean squared error (RMSE), mean absolute error
(MAE) and coefficient of efficiency (CE), between NEMS soil NO3–N and standard laboratory soil NO3–N measurements was excellent; (ii) at the field-scale, there was little practical difference when using either integer or
real number data processing; (iii) regression equations can be used to enable field measurements of soil NO3–N using the NEMS to be obtained with laboratory accuracy; (iv) future designs of the SNMS’s control system can continue to
use cheaper integer chip technology for processing the nitrate ion-selective electrode (NO3
−–ISE) readings; and (v) future designs of the SNMS would not need a soil moisture sensor, ultimately saving on manufacturing
costs of a more simple system. 相似文献
11.
缩节胺对棉花生长发育的调控效应研究进展 总被引：6，自引：0，他引：6
在棉花生产过程中运用缩节胺进行化学调控是我国发展轻简化棉花栽培技术的必然趋势。缩节胺对棉花生长发育的调控作用可以分为基本效应和复合效应2类,基本效应指喷施缩节胺后棉花在形态和功能上的直接变化,如农艺性状变化等;复合效应是指在基本效应的基础上,结合外界环境等其他因素共同作用后形成的变化,如产量性状变化等。重点讨论了缩节胺在棉花栽培上的使用技术,以及缩节胺对棉花种子萌发、根系活力、农艺性状、生理生化特性、产量及其构成因素、纤维品质和抗性的影响,同时还总结了缩节胺在目前生产中应用面临的问题,并对缩节胺化控在棉花育种上的应用前景进行了展望。 相似文献
12.
13.
中国棉花产业发展现状及展望 总被引：27，自引：1，他引：26
棉花是中国种植业生产中产业链最长的大田经济作物,其商品率高达95%以上,但棉花产业尚存在许多不足之处,需要涉棉企业、棉农、科技人员、学者进一步关注,如自主种业、品牌培育、清洁生产、统防统治、贸易依存度、产业安全、规模经济、产业组织等因素影响中国棉花的产业竞争力和可持续发展。中国棉花种植以新疆、黄河流域、长江流域为主,其中新疆棉花产量占全国产量的67%,已形成规模化和机械化种植,而长江、黄河流域仍以小规模种植为主,没有充分发挥新型经营主体的带动作用,无法形成规模化种植和机械化生产,且缺乏集棉花生产、加工、销售为一体的综合数据平台,在棉花的专业化服务、全程服务和托管式服务方面仅有数家。中国棉花产业未来发展方向和目标应是提升棉田生产规模化、机械化、智能化、信息化、服务社会化水平,研发轻简化生产技术使棉农有尊严快乐植棉,降低生产成本,解决谁来种地的问题,掌控棉花产业链条的主动权。文中从棉花产业链的供求角度出发,阐述了中国棉花种植面积和总产量大幅减少、产业布局上新疆一枝独秀、国内消费有所降低但供求形势有所好转、进口量长期大于出口量和纺织业优势递减的发展现状,分析了中国棉花产业在生产环节、产业布局、组织管理、平台建设等方面存在的问题,借鉴美国和澳大利亚在棉花品种、生产技术、机械化和国家政策的种植经验和发展优势,结合中国供给侧结构改革的政策背景,从培育棉花新品种、研发轻简化和机械化新技术、投入农机设备、优化品种品质和区域布局、科学防治病虫害提高棉花质量、制定棉花目标价格制度、提高棉花生产保险额度、加大对棉农、棉商、农机制造商、纺织企业、出口商等的补贴力度和政策保障力度、发挥产学研优势和棉花协会功能、构建产供销一体化平台、完善棉花供需调控体系、建设现代植棉业服务体系、借助“一带一路”契机带动棉花和纺织业走出国门等多个层面提出相应的对策建议,从而刺激国内有效供给,尽快实现中国棉花产业供需平衡。最后,对中国棉花产业进行展望,将“三去一降一补”应用于棉花产业,并顺应全球棉花去库存的格局,未来两年棉价将有所上涨。 相似文献
14.
Spring barley was grown for 4 years (2001–2004) in field trials at two sites on morainic soil in central SE Norway, with five N level treatments: 0, 60, 90, 120 and 150 kg N ha-1. Regression analyses showed that a selection of soil properties could explain 95–98% of the spatial yield variation and 47–90% of the yield responses (averaged over years). A strategy with uniform fertilizer application of 120 kg N ha−1 (U
N120) was compared with two variable-rate (VR) strategies, with a maximum N rate of either 150 kg N ha−1 (VRN150) or 180 kg N ha−1 (VRN180). These strategies were tested using either Norwegian prices (low price ratio of N fertilizer to yield value; PN/PY), or Swedish prices (high PN/PY). The VRN180 strategy had the highest potential yield and net revenue (yield value minus N cost) at both sites and under both price regimes. Using this strategy with Norwegian prices would increase the profit of barley cropping as long as at least 40 and 31% of the estimated potential increase in net revenue was realized, respectively. Using Swedish prices, uniform application appeared to be as good as or even better economically than the VR methods, when correcting for extra costs of VR application. The environmental effect of VR compared with uniform application, expressed as N not accounted for, showed contrasting effects when using Norwegian prices, but was clearly favourable using Swedish prices, with up to 20% reduction in the amount of N not accounted for. 相似文献
15.
Estimating soil organic carbon from soil reflectance: a review 总被引：1，自引：0，他引：1
Moslem Ladoni Hosein Ali Bahrami Sayed Kazem Alavipanah Ali Akbar Norouzi 《Precision Agriculture》2010,11(1):82-99
Soil organic carbon (SOC) concentration is a useful soil property with which to guide agricultural applications of chemical
inputs. To enable this, simple, accurate, rapid and inexpensive methods are needed to produce maps of surface SOC concentrations.
Researchers have investigated estimates of soil surface properties from remotely sensed information as a means of rapidly
quantifying and monitoring some surface soil properties, such as SOC. The objective of this paper is to review the potential
and limitations of remotely sensed data for mapping and evaluating SOC. Several statistical methods including simple regression
models, the ‘soil line’ approach, principal component analysis and geostatistics have been applied to data to investigate
the accuracy of such estimates. A review of the literature shows that predictive equations are not universal and require new
regression models for every scene. An important benefit of remotely sensed data is to suggest a sampling strategy that can
lead to improved representation of spatial heterogeneity in SOC. 相似文献
16.
A sensor for measuring crop biomass density has been designed and developed to meet the demands for practical use in site-specific
farming. The mechanical sensor named ‘Crop-meter’ is based on the pendulum principle. The suitability and measuring stability
of the Crop-meter has been confirmed under field conditions in different regions of Germany. Significant correlations were
obtained between Crop-meter signals and soil electrical conductivity (R
2=0.16−0.66) and grain yield (R
2=0.42−0.57). To test the suitability of the Crop-meter for site-specific management, it was used to control variable application
rates for nitrogen fertiliser, growth regulators and fungicides in real time. A small increase in yield (3.1%) as well as
reduced application rates for agrochemicals (14.6% nitrogen fertilisers; 23.1% fungicides and growth regulators) were proved
in large-scale trials. 相似文献
17.
Yuxin Yao Heng Zhai Lingling Zhao Kai Yi Zhi Liu Ye Song 《Frontiers of Agriculture in China》2008,2(4):463-466
It is necessary to find out the genetic characteristics of malic acid in the course of apple genomic research and breeding.
In this study, the SSR marker linked to the acid/low-acid trait in apple fruit was identified from 140 SSR primer pairs, using
91 F1 population hybrids from the intra-specific cross between apple cultivar ‘Dongguang’ and ‘Fuji’ as the experimental materials.
Of 140 SSR primer pairs, only primer SDY085 produced a polymorphic band linked to acid trait, and the linkage distance was
8.89 cM. Also, the titrated acid and malic acid in different developmental stages were determined. The SSR marker analysis,
coupled with the change of the total acid and malic acid contents, revealed that the acid/low-acid trait was governed by a
major gene and acid trait was completely dominant.
__________
Translated from Acta Horticulturae Sinica, 2006, 33(2): 244–248 [译自 : 园艺学报] 相似文献
18.
Yufeng Ge J. Alex Thomasson Ruixiu Sui Cristine L. Morgan Stephen W. Searcy Calvin B. Parnell 《Precision Agriculture》2008,9(4):181-194
A field study was conducted in 2006 in a dryland cotton field in Texas, USA, to explore the spatial variation of cotton fiber
quality and the loan rate associated with it. A total of 66 cotton samples were hand-harvested, and the fiber quality properties
investigated included the High Volume Instrument measurements of micronaire, length, uniformity, strength, elongation, reflectance
(Rd) and yellowness (+b). Conventional statistics showed a generally low level of variation in fiber quality with coefficients
of variation <10%. Variogram analysis showed that all fiber quality properties were spatially correlated. Contour maps of
individual fiber quality properties were produced from block kriged estimates. Fiber length, uniformity, strength and Rd were
positively correlated, and all of these were negatively correlated with +b. The spatial distribution of most fiber quality
properties was similar to that of soil apparent electrical conductivity, suggesting that water holding capacity could be a
limiting factor for cotton fiber quality. Maps of individual fiber quality properties were combined with the United State
Department of Agriculture—Commodity Credit Corporation Loan Schedule for Upland Cotton to create a loan rate map that is associated
with fiber quality. A loan rate difference of 20 cents kg–1 was observed within the field. This level of difference indicated that fiber quality at the field level can have a large
impact on producers’ revenue. A site-specific management system encompassing both lint yields and fiber quality is strongly
recommended for cotton production. 相似文献
19.
Acquirement of a new male sterile germplasm of Chinese jujube 总被引：2，自引：0，他引：2
A male sterile germplasm of Chinese jujube (Ziziphus jujuba Mill.), named ‘male sterile No.1’ (JMS1), was firstly identified from a natural population through studies of pollen amount
and vitality and its anatomy. Its microspores got massed and then disaggregated after the tetrad stage during pollen development.
Then its anthers became empty, or only pollen vestiges remained in the yellow buds. The pollen became abortive after the tetrad
stage. Hypertrophy and hyperplasia of tapetum at the tetrad stage were related to pollen abortion. In view of its moderate
embryo fertility, big fruit-size and early maturing, ‘JMS1’ could be used as a worthwhile female parent in the cross breeding
of Chinese jujube.
__________
Translated from Acta Horticulturae Sinica, 2006, 33(2): 374–377 [译自: 园艺学报] 相似文献
20.
Food regime theory focuses upon the dynamics, and agents, of change in capitalist food and farming systems. Its exponents
have been able to identify relatively stable periods of capital accumulation in the agri-food industries, along with the periods
of transition. Recently, scholars have argued that—following a first food regime based upon colonial trade in bulk commodities
like wheat and sugar, and a second food regime typified by industrial agriculture and manufactured foods—there is an emerging
third food regime. This new regime is one that is lead by global corporations that are profiting from the re-organisation
of agri-food chains. The delivery of ‘fresh/healthy’ foods is one manifestation; another is the sale, by supermarkets, of
ready-meals and other own-brand products. This paper argues that behind the movement to a putative Third Food Regime are changes
to the financial system. ‘Financialisation’—the increased influence of finance capital on the agri-food system—not only provides
new opportunities for profit-making by hedge funds and private equity consortia, but also creates a situation in which agri-food
companies, including food manufacturers, international commodity traders and supermarkets, may benefit. Supermarkets for example,
are moving into banking, and are altering their role as they move from being retailers of products, into the provision of
capital. Food regime theory needs to consider what lies ‘behind’ the transformation of food and fibre production, to examine
not only the role of finance capital in re-shaping relations up and down the agri-food supply chain, but also investigating
the tendency for agri-food capitals to seek profits from financial transactions. 相似文献