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1.
恩施旭田生态农业有限公司（以下简称旭田公司）坐落在贺龙曾经战斗过的地方，湖北省楚天明星乡镇--咸丰县忠堡镇明星村，这里土地肥沃、气候温和、雨量充沛，适合多种作物生长。忠堡资源丰富，方解石、重晶石、硫铁矿、锌矿、松香玉等矿石藏量可观。境内的忠建河是省级大鲵自然保护区。忠堡区位独特，地处咸丰、来凤、宣恩三县交界，是连接来凤、咸丰两县的重镇，猪、牛、家禽等养殖业发展迅速。 相似文献
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大棚苋菜高产高效栽培技术 总被引：1，自引：0，他引：1
早春采用大棚生产苋菜是武汉市新洲区双柳街菜农的创举,它打破了沿习千百年流传的"出汗"(夏季高温)时,才能吃到苋菜的常规,从20世纪80年代末期以来,棚栽苋菜一直成为当地农民早春种植的首选蔬菜,且种植规模逐年扩大,经济效益和社会效益非常显著.2004年双柳街全年种植棚栽苋菜面积920 hm2,一般1月开始播种,3月开始陆续上市,平均每667 m2产量2 000kg,产值3 000元.双柳的早春苋菜不仅满足了武汉春淡市场的需要,而且还销往周边省市,双柳苋菜2004年已通过中国绿色蔬菜认证.现将其栽培技术介绍如下. 相似文献
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1减产原因 1.1定植苗弱或带病 苗床土壤松软度不一致,不平整,播种后浇水时,土层下陷导致高低不平,使植株不能均势生长;育苗畦由于选择在地势低的地块,当雨水多时,排涝不及时,土壤中氧气不足,导致根系坏死;播种过密,分苗不及时,幼苗拥挤,徒长,根部染病;拔草不及时,草大伤苗. 相似文献
4.
9月,气温逐渐下降,要把握这个大好农时,继续种足管好秋播蔬菜.在秋播蔬菜生产中,菠菜是武汉地区栽培面积较多的一种蔬菜,最适宜的播种时期为平均气温稳定在17～20℃.在生产过程中,需氮、磷、钾完全肥料,如水肥供应不足、营养不良,则生长较弱、植株瘦小、叶片薄、味涩.播种的田块,要选择保水、保肥、富含有机质的沙壤土(夜潮土),播前要施足底肥.菠菜秋、冬、春三季均可播种.由于季节不同,气候各异,栽培技术各不一样,现结合生产实践,分述如下. 相似文献
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对我国农产品出口遭受绿色贸易壁垒阻碍的形式和原因进行了分析与综合,在此基础上提出了一些建议,旨在降低绿色贸易壁垒对现行我国农业的不利影响,推动我国农业朝着可持续绿色农业方向发展。 相似文献
7.
近年来,在果业气象服务与调查中,了解到果农在果树嫁接过程中存在与气象条件有关的问题,并进行了试验性嫁接.试验证明,就北方落叶果树而言,决定果树嫁接成活率高低的因素除砧木、接穗等自身条件外,还与气象条件中的温度、湿度、光照、降水、风有着密切关系. 相似文献
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9.
记者:可以介绍一下现阶段四季美的整体发展情况吗?
李华清:从2010年11月29日开业至今,武汉四季美农贸城的交易量逐年递增,平均增速10％.目前开业面积约26.7 hm2,档口300多个,齐聚了200多位老板,其中实力商户100多位.
菜品来自全国各地,外菜来自云南、广东、广西、山东和海南诸省,本地郊菜则来自东西湖、嘉鱼、长阳、恩施、襄樊等地.采购商户主要来自于华中五省,分别为湖北、江西、湖南、河南、安徽.当季交易量较大的蔬菜品种有辣椒、黄瓜、白萝卜、番茄、马铃薯和洋葱等. 相似文献
10.
大樱桃发展的形势、问题及建议 总被引：3，自引：0，他引：3
近几年,苹果、梨、葡萄等大宗水果过剩,价格下降.随着果业结构调整,小杂果不断升温,发展大樱桃热潮迭起,一些历史上栽培大樱桃很少的地区,把发展大樱桃作为重点,规划千亩、万亩基地,大批量从大樱桃主产区调人苗木,或在当地大面积育苗.随着大樱桃生产的发展,问题也不断出现,就此,谈点个人看法. 相似文献
11.
Fruit cracking after rain limits the production of a number of crops, including some Ribes species. To gain a better understanding of the factors involved in cracking, fruit growth, deposition of the cuticular membrane (CM), water uptake and fruit cracking were studied in black currant (Ribes nigrum L. cv. Zema), gooseberry (Ribes uva-crispa L. cv. Rote Triumph), and jostaberry (Ribes nidigrolaria B. cv. Jostine). Fruit surface area and fresh mass increased continuously throughout development, whereas deposition of the CM was biphasic. CM mass per fruit increased rapidly up to 42, 41, and 49 days after full bloom (DAFB) in black currant, gooseberry, and jostaberry, respectively. Thereafter, CM mass per fruit remained constant in gooseberry and jostaberry or increased at a lower rate in black currant. The cessation of or reduced rate of CM deposition resulted in a decrease in CM mass per unit area in all berries. Elastic strain of the CM at maturity averaged 23.8% and 19.5% in gooseberry and jostaberry, respectively, and only 8.2% in black currant. Microcracks in the CM were observed first in gooseberry and jostaberry 64 DAFB, whereas there were no microcracks in black currant. Water uptake into mature detached berries was linear over 2 h of incubation. Rates of uptake were highest in gooseberry followed by black currant and jostaberry. Relative uptake was similar via the cut end of the pedicel (32.1%), the apex of the fruit (34.7%) and the fruit surface (33.2%). Rates of water uptake through the fruit surface were positively related to surface area. Average fruit water potential for black currant, gooseberry, and jostaberry was −2.14 ± 0.17, −1.24 ± 0.03, and −1.89 ± 0.20 MPa, while the permeability for osmotic water uptake was 7.7 ± 0.4 × 10−8, 5.2 ± 0.1 × 10−8, and 3.3 ± 0.3 × 10−8 m s−1. Incubating whole fruit in deionized water for 72 h resulted in more cracked jostaberries (94%) than black currants (74%) or gooseberries (50%). A comparison of our findings in Ribes berries with published data for the sweet cherry drupe revealed that the berries fitted the relationships established in sweet cherry among fruit growth, cuticle deposition, strain of the cuticle, microcracking, permeability for osmotic water uptake, frequency of stomata and cracking. The Ribes berries were less susceptible to cracking than sweet cherry. 相似文献
12.
Robert Rosen 《Landscape Ecology》1989,3(3-4):207-216
An exceptionally rich and colorful literature, drawn in almost equal parts from pure mathematics, from the sciences, and from the technologies, has grown up over the years, which bear in different ways on the topics under discussion. It is the intent of the present paper to survey this far-flung literature, point out some of the commonalities and interrelationships which underlie it, and briefly indicate how it has been and can be applied. To my knowledge, this kind of review has not been attempted before. 相似文献
13.
Wetlands, carbon, and climate change 总被引：3，自引：0，他引：3
William J. Mitsch Blanca Bernal Amanda M. Nahlik Ülo Mander Li Zhang Christopher J. Anderson Sven E. Jørgensen Hans Brix 《Landscape Ecology》2013,28(4):583-597
Wetland ecosystems provide an optimum natural environment for the sequestration and long-term storage of carbon dioxide (CO2) from the atmosphere, yet are natural sources of greenhouse gases emissions, especially methane. We illustrate that most wetlands, when carbon sequestration is compared to methane emissions, do not have 25 times more CO2 sequestration than methane emissions; therefore, to many landscape managers and non specialists, most wetlands would be considered by some to be sources of climate warming or net radiative forcing. We show by dynamic modeling of carbon flux results from seven detailed studies by us of temperate and tropical wetlands and from 14 other wetland studies by others that methane emissions become unimportant within 300 years compared to carbon sequestration in wetlands. Within that time frame or less, most wetlands become both net carbon and radiative sinks. Furthermore, we estimate that the world’s wetlands, despite being only about 5–8 % of the terrestrial landscape, may currently be net carbon sinks of about 830 Tg/year of carbon with an average of 118 g-C m?2 year?1 of net carbon retention. Most of that carbon retention occurs in tropical/subtropical wetlands. We demonstrate that almost all wetlands are net radiative sinks when balancing carbon sequestration and methane emissions and conclude that wetlands can be created and restored to provide C sequestration and other ecosystem services without great concern of creating net radiative sources on the climate due to methane emissions. 相似文献
14.
J. Van Bragt 《Scientia Horticulturae》1982,17(2):199
15.
Harold S. J. Zald Thomas A. Spies Manuela Huso Demetrios Gatziolis 《Landscape Ecology》2012,27(8):1197-1212
Tree invasions have been documented throughout Northern Hemisphere high elevation meadows, as well as globally in many grass and forb-dominated ecosystems. Tree invasions are often associated with large-scale changes in climate or disturbance regimes, but are fundamentally driven by regeneration processes influenced by interactions between climatic, topographic, and biotic factors at multiple spatial scales. The purpose of this research was to quantify spatiotemporal patterns of meadow invasion; and how climate, larger landforms, topography, and overstory trees have interactively influenced tree invasion. We combined airborne Light Detection and Ranging (LiDAR) characterizations of landforms, topography, and overstory vegetation with historical climate, field measurements of snow depth, tree abundance, and tree ages to reconstruct spatial and temporal patterns of tree invasion over five decades in a subalpine meadow complex in the Oregon Cascade Range, USA. Proportion of meadow occupied by trees increased from 8?% in 1950 to 35?% in 2007. Larger landforms, topography, and tree canopies interactively mediated regional climatic controls of tree invasion by modifying depth and persistence of snow pack, while tree canopies also influenced seed source availability. Landscape context played an important role mediating snow depth and tree invasion; on glacial landforms tree invasion was negatively associated with spring snowfall, but on debris flows tree invasion was not associated with snow fall. The importance of snow, uncertain climate change impacts on snow, and mediation of snow by interacting and context dependent factors in complex mountain terrain poses substantial hurdles for understanding how these ecotones may respond to future climate conditions. 相似文献
16.
Ralph E. J. Boerner 《Landscape Ecology》2012,27(8):1235-1236
17.
AIM: To detect the treatment of K562 leukemia cells with bortezomib altering the expression of genes fas, bcl-2, bcl2l12, bim, bax, caspase-9 and caspase-3.METHODS: MTT assay was used to detect the inhibition of proliferation. Apoptosis was detected by Annexin-V staining and mitochondrial transmembrane potential (Δψm). RT-PCR was used to analyze the mRNA expressions of fas, bcl-2, bcl2l12, bim, bax, caspase-3 and caspase-9.RESULTS: Bortezomib caused a time- and dose-dependent inhibition of cell proliferation and IC50 of 24 h and 48 h were 161.41 nmol/L and 96.33 nmol/L, respectively. At the concentration of 104 nmol/L, bortezomib induced apoptosis in a time-dependent manner, including increasing annexin-V positivity and decreasing the Δψm. RT-PCR showed that bortezomib up-regulated the mRNA expression of fas, bcl2l12, caspase-9 and caspase-3, but mRNA expressions of bcl-2, bim and bax did not changed obviously.CONCLUSION: Bortezomib inhibits the proliferation of K562 and induces apoptosis, in which fas, bcl2l12, caspase-9 or caspase-3 gene is one of the main genes taking part in. 相似文献
18.
K.C. Sink 《Scientia Horticulturae》1978,8(1):91-92
19.
氮磷钾硼肥配施对青花菜养分吸收分配及产量和品质的影响 总被引：4，自引：0，他引：4
研究了不施肥处理,氮磷钾配施和增施硼肥对青花菜养分吸收分配及产量和品质的影响。结果表明,现蕾期至花球膨大期,青花菜对氮、磷、钾的吸收量最大,整个生长期对钾的吸收最多,氮次之,磷最少。氮磷钾主要分配在叶片中,现蕾后逐渐向花球转移,从现蕾到采收时,叶片中氮、磷、钾分配率分别降低了19.6%、10%和9.0%,花球中氮磷钾分配率分别提高了23.1%、15.9%和11.1%。不施氮、磷、钾肥显著降低了花球产量、维生素C含量和成品率,增施硼肥处理的花球成品率较氮磷钾肥处理提高了4.8%,不施氮肥和钾硫肥(K2SO4)显著降低了花球中的硫代葡萄糖苷含量。相关性分析表明,青花菜产量与植株内氮、钾积累量显著正相关,成品率与植株内磷营养显著正相关。 相似文献
20.
August De Hertogh 《Scientia Horticulturae》1974,2(4):313-355
Systematic investigations on the forcing of tulips, hyacinths, daffodils, Easter lilies and Dutch iris have produced a fairly complete set of scientific principles. In this review, these principles have been classified into a 3-phase concept of forcing. These are: production, programming, and greenhouse. The production phase is defined as all processes which occur during bulb production and it terminates with the harvesting of the bulbs. The programming phase comprises all handling of the bulbs from harvesting until they are placed under greenhouse conditions. The greenhouse phase is the accelerated development of the bulbs until anthesis or marketing of the plants. These phases have been discussed relative to floral and root development and the basic environmental requirements of the bulb species. 相似文献