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一、概述及其摘要
全面介绍超低量（施肥施药）技术的性能特点,增产机理及其在农业生产过程中应用。通过试验示范,证明超低量（施肥施药）技术在现有施肥施药费用的基础上,减少一半投入的情况下,解决了常规技术无法解决的七大难题,并能满足农作物优质高产的条件需求。超低量（施肥施药）技术为农业的可持续发展;农民多渠道增收致富;农产品质量安全,扩大出口创汇;国富民强,保障人民身体健康开辟了新的途径。 相似文献
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柑桔“五改”丰产技术的探索 总被引：1，自引：0，他引：1
为探索柑桔低成本高产优质的栽培管理技术 ,我们于 1 997～ 1 999年连续 3年在重庆市铜梁县果树研究所示范园进行试验 ,总结出一套优质高产低成本的柑桔园简易管理技术 ,即“五改”丰产技术。采用此技术 ,一个成年劳动力可以管理0 .4～ 0 .6ｈｍ2 密植园 ,且施药量减少 ,产量提高 ,品质变优 ,成本降低。示范园 8年生新生系 3号柑 (株行距 3ｍ× 2ｍ)每 6 6 7ｍ2 产量高达 40 0 0ｋｇ,平均单果重 1 6 8ｇ;7年生铜梁锦橙 (3ｍ× 1 .5ｍ)产量达 370 0ｋｇ,平均单果重 2 0 5ｇ。1 改革施肥技术 改 1年 4次施肥为 3次施肥 ,改冬施基肥为夏… 相似文献
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赣南脐橙产区2016年嫩梢期由专业防治组织实施了直升机施药防治柑桔木虱作业,为评估防治效果,开展了相关调查研究。结果表明,直升机施药雾化性能较好,雾滴附着率高,雾滴分布较均匀,14个作业(处理)的607个雾滴检测样本的平均雾滴密度为13.33粒/cm~2,符合农业航空植保技术作业要求;各处理对柑桔木虱均有很好的防治效果,药后7d有13个处理的防治效果达90%以上。直升机施药能在短时间内大面积作业,解决了一家一户防治时间不统一的问题,可以大面积减少虫口基数,是柑桔黄龙病发生区可以借鉴应用的重要技术措施。 相似文献
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果树营养与施肥是果树栽培中的基础环节。科学施肥是保证果树高产、稳产、优质的最有效的措施。为了解决果园土肥水管理中存在的一些问题,为建设高标准果园提供技术指导,我们特邀请中国农业科学院郑州果树研究所土壤肥料专家黄显淦研究员以自己多年的工作实践,撰写了以下系列专题讲座:1.果树营养与施肥种类;2.果树施肥适宜时期、方法和数量;3.关于果园有机肥的施用;4.几种果树施肥方法简介;5.果树叶面喷肥技术;6.果园土壤管理;7.果园土壤改良的基本技术措施;8.对果园类型建立及钙、钾肥施用重要性的看法。本刊从2015年第1期起陆续刊出,以飨读者。 相似文献
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果树营养与施肥是果树栽培中的基础环节。科学施肥是保证果树高产、稳产、优质的最有效的措施。为了解决果园土肥水管理中存在的一些问题,为建设高标准果园提供技术指导,我们特邀请中国农业科学院郑州果树研究所土壤肥料专家黄显淦研究员以自己多年的工作实践,撰写了以下系列专题讲座:1.果树营养与施肥种类;2.果树施肥适宜时期、方法和数量;3.关于果园有机肥的施用;4.几种果树施肥方法简介;5.果树叶面喷肥技术;6.果园土壤管理;7.果园土壤改良的基本技术措施;8.对果园类型建立及钙、钾肥施用重要性的看法。本刊将从2015年第1期起陆续刊出,以飨读者。 相似文献
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ｌ 柑橘１．１ 施肥 即为壮果肥,于 ６月底至 ７月中旬施入,作用是促进果实膨大,增加产量。肥料以速效性肥料为主,可配用腐熟的有机肥。海涂橘园或(特)早熟温州蜜柑如采用一年一次施肥,此次肥料一般不施;应用全年２次施肥法,大年树应施入总肥量２/３肥料,小年树应施入总肥量１/３肥料;应用一年三次施肥法应施入全年总肥量的 相似文献
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雾滴密度、药液量和器械对苹果全爪螨防效的影响 总被引：1，自引：0，他引：1
《果树学报》2016,(1)
【目的】研究3%阿维菌素微乳剂施药的雾滴密度、药液量及器械对苹果全爪螨防效的影响,为解决目前果园淋洗式的施药方式提供技术参数和理论依据。【方法】根据3%阿维菌素微乳剂防效确定施药雾滴密度和药液沉积量;根据2种器械施药后药液在树体分布均匀性、叶片上的沉积量和防效,获得适合苹果园防治苹果全爪螨的施药器械。【结果】3%阿维菌素微乳剂3 000倍、高密度、有效成分沉积量为0.207μg·cm-2,对苹果全爪螨的防效可超过92.01%;弥雾喷雾机在果园中施药均匀,流失量小,3%阿维菌素微乳剂3 000倍、每株施药量2~3 L,7 d防效超过95.07%;柱塞泵喷雾机施药不均匀、流失量高,每株施药量4~5 L,7 d防效超过92.08%,每株3 L施药量7 d防效小于90%。【结论】目前生产上使用3%阿维菌素微乳剂防治苹果园苹果全爪螨时,施药量高、效果差,造成浪费和污染严重,防治时应优先选择弥雾喷雾机,进行低药量施药。 相似文献
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The riparian forests along braided rivers are dynamic, frequently rejuvenated by floods and channel changes, and thus dominated
by pioneer to middle stages of succession; they are sites of high biodiversity in some regions. The Lower Eygues River (drainage
area 1150 km2 in southeastern France) is such a braided river system with large alluvial forests dominated by Salix alba, Populus alba, and P. nigra. It was identified as a site of ecological interest by the EU under the Natura 2000 program. Such forests elsewhere in Europe have been identified as reference ecosystems. We documented the historical evolution
of this alluvial forest from detailed (1:2500 scale) early 19th C parcel maps, early 20th C topographic maps, aerial photography
from 1947 to 1996, and field surveys of topography and riparian vegetation in 1997–1998. Our results show that in 1830, the
channel was wide, aggraded, and agricultural pressure extended literally to the channel edge. With decline in the rural population
and reduced agricultural and grazing pressure in the catchment, erosion rates declined. Reduced sediment supply led to channel
narrowing and incision. This channel narrowing, coupled with reduced agricultural pressure along the banks, has allowed riparian
forest to colonize former active channel areas, especially within late 19th-century 20th century flood dykes. In recent decades,
aggregate mining, and clearing for recreation and agriculture have fragmented the forest. Thus, the alluvial forest of the
Lower Eygues is largely an artifact of changing human land-use over the past century, a context that should frame efforts
for preservation and restoration. 相似文献
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Steven Walters 《Landscape Ecology》2007,22(6):867-881
Understanding the impacts of habitat fragmentation on dispersal is an important issue in landscape and conservation ecology.
Here I examine the effects of fine- to broad-scale patterns in landscape structure on dispersal success of organisms with
differing life-history traits. An individual-based model was used to simulate dispersal of amphibian-like species whose movements
were driven by land cover and moisture conditions. To systematically control spatial pattern, a landscape model was created
by merging simulated land cover maps with synthetic topographic surfaces. Landscapes varied in topographic roughness and spatial
contagion in agriculture and urban land cover. Simulations included three different species types that varied in their maximum
potential dispersal distances by 1-, 2-, or 4-fold. Two sets of simulations addressed effects of varying aspects of landscape
structure on dispersal success. In the first set of simulations, which incorporated variable distances between breeding patches,
dispersal success was lowest for all species types when anthropogenic cover was patchily distributed. In the second set, with
interpatch distances held constant as landscape composition varied, dispersal success decreased as anthropogenic cover became
spatially contagious. Both sets revealed strong main effects of species characteristics, interpatch distances and landscape
composition on dispersal success; furthermore, scale-dependent patterns in land cover and moisture gradients had a stronger
effect on longer- than shorter-ranging species types. Taken together, these simulations suggest that heuristic conservation
strategies could potentially be developed based on important but limited life history information. 相似文献
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AIM: To investigate the levels of IL-18, IL-16, IL-8, eotaxin and the chymase activity in the sputum of asthmatics. METHODS: IL-18, IL-16, IL-8 and eotaxin levels were detected with sandwich ELISA procedures and chymase activity was determined spectrophotometrically (410 nm) by the rate of hydrolysis of N-succinyl-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroanilide (SAAPP). RESULTS: The specific chymase activities in the severe and moderate asthmatics were higher than that in controls. Native protease inhibitors α1-antitrypsin (α1-AT) and soybean trypsin inhibitor (SBTI) inhibited 71.9% and 72.1% enzymatic chymase activity, respectively. The levels of IL-18, IL-16, IL-8 and eotaxin were significantly elevated in the sputum of patients with acute asthma. There were correlations between the levels of IL-8 and IL-16 (r=0.55, P<0.05), IL-8 and eotaxin (r=0.41, P<0.05), IL-18 and IL-16 (r=0.64, P<0.01), IL-18 and eotaxin (r=0.66, P<0.01)，IL-16 and eotaxin (r=0.64, P<0.01), but they all failed to correlate with neutrophils, epithelial cells, lymphocytes and macrophages. CONCLUSION: The levels of IL-18， IL-16， IL-8， eotaxin and the activity of chymase were elevated in the sputum of the patients with asthma, indicating that they may play a role in the pathogenesis of asthma. 相似文献
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Many nnewly discovered interleukins have been implicated to play an important role in the pathogenesis of the allergic diseases, for example, human interleukin (IL)-17, a T-cell derived cytokine; interleukin (IL)-18, an interferon (IFN)-gamma-inducing cytokine; interleukin (IL)-23, produced by activated dendritic cells, and interleukin (IL)-25, a recently described T helper 2 (Th2) cell-derived cytokine. Understanding their characteristic and roles in diseases may help us to know better the mechanism of the allergic diseases and develop the strategy for treating the disease. 相似文献
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氮磷钾施用量与洋葱产量的相关性研究 总被引：1，自引：0，他引：1
采用3因素2次回归通用旋转设计,对N、P、K施用量与洋葱产量的相关性进行了研究,并分别建立了3元2次回归方程.结果表明:N、P、K皆有利于洋葱的形成,P对洋葱产量的影响较大,在土壤缺P地区应重视P肥的施用;3因素在影响洋葱产量上存在交互作用;经计算机模拟,N、P、K最佳组合方案为:12.5 kg/667 m2、20.0 kg/667 m2、3.0 kg/667 m2,洋葱产量最高可达7 440.2 kg/667 m2. 相似文献
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Monjeau J. Adrian Birney Elmer C. Ghermandi Luciana Sikes Robert S. Margutti Laura Phillips Carleton J. 《Landscape Ecology》1998,13(5):285-306
Assemblages of plants were studied at 14 sites in northern Patagonia corresponding to localities at which we (Monjeau et al. 1997) earlier studied the relationship between small mammal assemblages and landscape classifications. This allowed us to test predictions that both plants and small mammals correspond to the more inclusive hierarchical landscape divisions but that plants track better than small mammals the less inclusive divisions. Species presence or absence of plants at each locality was used in a series of multivariate analyses and compared by correlation analysis with those generated from small mammal species data. Assemblages of both plants and small mammals corresponded to the upper divisions, which are based on climatic and geomorphological features, but small mammal assemblages did not correspond to the lower divisions of the landscape classifications. Three factors are considered as explanations for the observed differences between plants and small mammals: a) small mammal habitat is determined more by plant growth form than by plant species; b) trophic level differences between the two groups; and c) species pool size affects the resolution of microhabitat correspondence. Our data indicate that both plant assemblages and small mammal assemblages respond to climatic and geomorphological features, which is in contrast to the paradigm that mammal assemblages simply follow plant assemblages. We also attempted to reconcile classification systems in Patagonia by proposing a nomenclatural system based on a hierarchical classification. In the system proposed, ecoregion is the lowest division small mammal assemblages can recognize in Patagonia. Finally, we conclude that the hierarchical nature of landscapes based on a holistic view of environments reflects real entities that are not just the perceptions of landscape ecologists. 相似文献
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A computer simulation model was used to derive estimates of the probability of extinction of populations of the endangered species, Leadbeater's Possum (Gymnobelideus leadbeateri), inhabiting ensembles of habitat patches within two wood production forest blocks in central Victoria, south-eastern Australia. Data on the habitat patches were extracted from forest inventory information that had been captured in the database of a Geographic Information System (GIS). Our analyses focussed on a range of issues associated with the size, number and spatial configuration of patches of potentially suitable habitat that occur within the Ada and Steavenson Forest Blocks. The sensitivity of extinction risks in these two areas to variations in the movement capability ofG. leadbeateri was also examined.Our analyses highlighted major differences in the likelihood of persistence of populations ofG. leadbeateri between the Ada and Steavenson Forest Blocks. These were attributed to differences in the spatial distribution and size of remnant old growth habitat patches as well as the impacts of wildfires. In addition, simulation modelling revealed a different relative contribution of various individual patches, and ensembles of patches, to metapopulation persistence in the two study areas. In those scenarios for the Ada Forest Block in which the impacts of wild-fires were not modelled, our analyses indicated that a few relatively large, linked patches were crucial for the persistence of the species and their loss elevated estimates of the probability of extinction to almost 100%. A different outcome was recorded from simulations of the Steavenson Forest Block which, in comparison with the Ada Forest Block, is characterized by larger and more numerous areas of well connected patches of old growth forest and where we included the impacts of wildfires in the analysis. In this case, metapopulation persistence was not reliant on any single patch, or small set of patches, of old growth forest. We found that in some circumstances the probability that a patch is occupied whilst the metapopulation is extant may be a good measure of its value for metapopulation viability. Another important outcome from our analyses was that estimates of extinction probability were influenced both by the size and the spatial arrangement of habitat patches. This result emphasizes the importance for modelling metapopulation dynamics of accurate spatial information on habitat patchiness, such as the data used in this study which were derived from a GIS.The values for the predicted probability of extinction were significantly influenced by a range of complex inter-acting factors including: (1) the occurrence and extent of wildfires, (2) the addition of logging exclusion areas such as forest on steep and rocky terrain to create a larger and more complex patch structure, (3) estimates of the quality of the habitat within the logging exclusion areas, and (4) the movement capability ofG. leadbeateri. Very high values for the probability of extinction of populations ofG. leadbeateri were recorded from many of the simulations of the Ada and Steavenson Forest Blocks. This finding is the result of the limited areas of suitable old growth forest habitat for the species in the two areas that were targeted for analysis. Hence, there appears to be insufficient old growth forest in either of the two forest blocks to be confident that they will support populations ofG. leadbeateri in the long-term, particularly if a wildfire were to occur in the next 150 years.The results of sensitivity analyses indicated that estimates of the probability of extinction ofG. leadbeateri varied considerably in response to differences in the values for movement capability modelled. This highlighted the need for data on the dispersal behaviour of the species. 相似文献
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氮、磷、钾肥对红枣产量和品质的影响 总被引：3，自引：0，他引：3
研究了氮磷钾肥对6a树龄红枣产量和品质的影响。结果表明:新疆南部红枣最高产量施肥量为N691.5 kg/hm2,P2O5 577.5 kg/hm2,K2O 72 kg/hm2,施用比例1:0.84:0.11。采用平衡施肥能增加红枣产量,降低红枣果实中总酸度,并能增加红枣果实中水解还原糖和VC含量,从而提高红枣产品品质,增加效益。红枣果实中总酸度随氮肥施用量增加而增加;磷钾肥能降低总酸度。当氮、磷、钾肥分别控制在600、180～450、75kg/hm2时能显著提高红枣果实中水解还原糖和VC含量。 相似文献
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The understanding of cross-cultural upon park usage is vital to be enhanced among public since findings that been discovered in the Western context are not own any similarities with the Asian context. In fact, it has been in a long run for the Western nations to primarily contextualized and conceptualized much on the literature of park usage. This study aims to look at how the people use and perceive urban parks in their daily life in the Malaysian cultural context, and also highlights the constraints faced by Malaysians while using the urban parks in the city of Kuala Lumpur. A survey consisted of 669 urban park users as the sample of the study (365 men, 304 females) aged between 18 and 73 years (M = 34.85, SD = 11.46) were conducted in five urban parks in Kuala Lumpur. Respondents were recruited based on a random sampling method, which composed of three main ethnic groups in Malaysia. Malaysians wanted to use the urban parks for multiple purposes including active activities and others. Most of them would visit the parks and spend their time in a group consisting of family members or friends rather than alone. The percentage of respondent with 74.7% stated their reason of visiting the urban park in order “to get fresh air”, followed by the factor of reducing stress and relaxing with 69.7%; and the latter reason would be “to exercise, play games or keep in shape” with 61.4%. More than 80% of the respondents claimed the parks in Kuala Lumpur are safe to be visited. This is because, majority of the respondents tend to visit the parks in group of family or friends rather than alone. In addition, most of the respondents would run their activities in parks during the weekends, which simultaneously make them to enjoy their day in such comfortable and secure way. The findings of this survey would contribute to a better understanding of the present park usage of Kuala Lumpur residents. With a better understanding of current park-visiting habits, various constraints faced by the residents related to public security and safety, the Kuala Lumpur City Hall have been suggested to develop more comprehensive strategy in order to provide engagement and urban parks stimulation for its residents. In addition, this study is also fruitful for Kuala Lumpur future parks in terms of its development, design and management. 相似文献