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1.
刘祥学 《热带地理》2013,33(6):748-755
水稻种植过程中,常具有浓厚的环境适应的特征。分布在不同地貌区的壮族是典型的稻作民族,已充分意识到所在地区气候、土壤等自然地理环境对水稻种植的深刻影响。为适应自然地理环境,发挥最大的生产效益,山居壮族多选择种植生长期较长、耐寒、耐肥的粳稻为主;在平原丘陵地区的壮族则以种植生长期短的籼稻居多;为适应岩溶山区干旱少水、不利于灌溉的环境,当地壮族则多种陆稻,但由于陆稻口感不佳以及所在地区人地关系由宽趋紧,导致陆稻在壮族种植结构中的地位不断下降。此外,壮族在生活中对水稻用途的定位,也影响到水稻品种的选择与种植。  相似文献   

2.
稻田CH4排放研究进展   总被引:4,自引:0,他引:4  
CH4是引起全球变暖的温室气体之一,稻田是CH4的重要排放源.对稻田CH4的最新研究进展作了较为详尽的综述,包括稻田CH4排放的机制和规律,重点分析了影响稻田CH4排放的因素,指出今后的研究重点应以现有的田间数据为基础,定量说明不同环境因素在CH4产生、排放中的贡献率,完善实验方法,使实验方法具有统一模式,建立稻田温室气体排放的综合模型,预测稻田温室气体排放变化。  相似文献   

3.
生态和文化因素对农作物品种的选育和分布起着十分重要的影响。本研究利用稻作品种的空间分布数据库,探讨了云南地区稻作品种多样性的分布中心及其与生态、文化因素之间的联系。研究结果表明,云南地区稻作品种多样性的分布中心主要集中在滇南、滇西南和滇东南地区。这可能与当地温暖、湿润的气候和特有的稻作文化有关。对滇南多样性分布中心而言,傣族和哈尼族的稻作文化起着重要影响;对滇西南多样性分布中心而言,起重要影响的稻作文化主要来自傣族,景颇族和拉祜族;而对滇东南分布中心而言,苗族、瑶族和壮族的稻作文化则起着相对更为重要的影响。传统文化不仅促进了稻作品种的选育,同时,丰富的稻作品种也有利于稻作文化的保存和延续。  相似文献   

4.
黑龙江省冷害对水稻产量的影响   总被引:11,自引:3,他引:8  
以黑龙江省为例, 比较了在大尺度范围内、利用传统的站点平均法以及基于格点水稻密度分布的泰森多边形面积权重法所得的两种省级水稻气象数据差异, 并分析了1960-2009 年内, 不同时间尺度上温度和降水的变化趋势特点。针对当地水稻低温冷害频发及其危害严重的实际情况, 对比研究了气象行业标准(QX/T 101-2009) 和国家标准中有关低温冷害的指标定义, 以及国际上较通用的有效负积温算法(GDDn-) 这三种指标在反映黑龙江省水稻冷害事件上的能力, 结果表明:气象行业标准可以较好地反映延期型冷害对水稻的影响, 而GDD指标在反映障碍型冷害上均优于气象行业及国家标准。利用时间序列模型对包含延迟型和障碍型两种冷害影响的黑龙江省水稻产量进行拟合, 回归方程的解释能力可达92% (p < 0.05)。本研究定量得出了人为因素和气象因素对黑龙江省水稻生产的影响分别占87.2%和12.8%的结论, 并检测出近年来水稻抽穗开花期障碍型冷害的波动增加趋势, 为明确今后低温冷害的防御重点提供科学参考。  相似文献   

5.
寒地水稻障碍型冷害指数构建及应用——以辽宁省为例   总被引:1,自引:0,他引:1  
东北地区水稻障碍型冷害常规评估多采用温度和低温持续天数2个指标,为实现定量化评估和预报,需构建一种基于多因素的综合性障碍型冷害指数。本文基于水稻温度适宜度模型,以温度和低温持续天数为基础,综合考虑三基点温度对水稻生长发育过程的影响,利用辽宁省近50年的日平均温度和水稻发育期数据,构建水稻障碍型冷害指数(RSCDI),并利用该指数对辽宁省水稻障碍型冷害变化规律进行分析和试预报。结果表明:①1961-2010年的50年间,有20年发生了局部轻度冷害,14年发生了局部中度冷害,10年发生了局部重度冷害,未发生区域性及大范围冷害。②冷害发生频率最高的年代为1971-1980年,1981-2000年发生频率呈下降趋势,发生频率最低的年代为1991-2000年,2001年以后发生频率上升、且范围呈现扩大趋势;冷害发生范围主要分布在辽宁西部和东北部地区。随着气候变暖,冷害发生频率和范围虽有一定程度的下降,但辽宁省水稻障碍型冷害发生的不确定性仍存在。③利用RSCDI对2011-2014年辽宁省水稻障碍型冷害进行试预报,结果仅建平县2012年和2014年在开花期发生中度冷害,其他地区无冷害发生。  相似文献   

6.
近20年气候变暖对黑龙江省水稻增产的贡献   总被引:35,自引:1,他引:34  
方修琦  王媛  徐锬  云雅如 《地理学报》2004,59(6):820-828
研究过去的气候变暖对作物产量的影响是认识变暖对农业影响的有效途径,但如何定量区分出气候变化和技术发展对粮食作物的影响程度是目前研究的难点。本文提出的算法在一定程度上可以克服传统算法缺陷,用此方法估算过去20年气候变暖对黑龙江省水稻单产增加的贡献率,结果表明:20世纪80年代相对于70年代水稻单产增加了30.6%,其中由气候变暖带来的增产量占实际增产量的12.8%~16.1%,相当于使70年代的单产增加3.9%~4.9%。20世纪90年代水稻单产较80年代增产42.7%,其中,气候变暖对单产增加的贡献率约为23.2%~28.8%,相当于在20世纪80年代的单产水平上增产9.9%~12.3%。  相似文献   

7.
湖南省地形因素对水稻生产的影响   总被引:3,自引:0,他引:3  
王琛智  张朝  张静  陶福禄  陈一  丁浒 《地理学报》2018,73(9):1792-1808
作为一种人工生态系统,水稻的生产受自然条件和人为管理的共同影响。其中,地形因素不仅决定了水稻生长必须的光热等资源的再分配,而且还影响人类的农业管理活动。以中国水稻主产区中地形较为复杂的湖南省为研究对象,基于多种数据,从生态学的“格局—过程”思想出发,讨论了地形因素对水田分布、水稻生长过程及水稻产量的影响。研究发现,地形因素对水田分布的空间格局影响最为明显,对水稻生长过程影响次之,而对水稻产量影响较弱。在各地形因素中,高程对于水稻生产的影响最为突出。研究结果还反映出地形因素造成了湖南省水田分布和热量分配在北部平原地区的不匹配,政府部门应根据区域特征,因地制宜采取措施,提高该地区水稻生产效益。  相似文献   

8.
淮河流域单季稻气候风险研究   总被引:3,自引:1,他引:2  
俞芬  千怀遂  段海来 《地理科学》2011,31(4):501-507
综合考虑单季稻气候适宜性水平及其变率变化,构建单季稻的风险度模型,运用滑动建模技术对淮河流域单季稻的气候风险性进行了动态分析与评估。根据风险分布将淮河流域单季稻温度、降水、日照和气候风险大致分为三种类型:低风险型、中风险型和高风险型;在时间变化上,近几十年来,淮河流域单季稻气候风险度有逐渐增加的趋势;并随着时间的推移,在空间上东部风险较低的区域有逐渐降低的趋势,而西部气候风险高的地区有进一步增大并向东部沿海扩展的趋势。  相似文献   

9.
ABSTRACT

How can indigenous communities in illiberal regimes benefit from oil production? This paper compares the experience of two indigenous peoples in the Russian Arctic, the Nenets and the Komi-Izhemtsi, in their quest for environmental protection and the development of benefit-sharing arrangements with Lukoil, a Russian oil company. The Nenets people, recognized by the Russian state as indigenous, are marginalized political actors who identified a route to receiving compensation for loss of land and damage to the environment as well as economic benefits under the auspices of Russian law and Lukoil’s corporate policies. In contrast, the Komi-Izhemtsi, despite indigenous status in global institutions including the United Nations and the Arctic Council, are unrecognized as indigenous domestically and initially received no compensation. Their path to benefit sharing was more challenging as they partnered with local nongovernmental organizations and global environmentalists to pressure Lukoil to sign a benefit-sharing agreement. Ultimately, the comparison illustrates how transnational partnerships can empower indigenous people to gain benefits from natural resource exploitation even in illiberal political systems.  相似文献   

10.
基于水稻和银杏混合区的TM影像,分别引入NDII及NDVI提取研究区水稻信息,通过总量精度和位置精度的对比,发现NDII提取结果均优于NDVI。对研究区水稻和银杏样点的NDVI值和NDII值进行对比,发现其NDVI值相近,而NDII值相差较大。这从另一方面解释了利用NDII提取水稻结果优于NDVI。  相似文献   

11.
淮河流域水稻的气候适宜度及其变化趋势分析   总被引:17,自引:2,他引:15  
俞芬  千怀遂  段海来 《地理科学》2008,28(4):537-542
淮河流域40个县(市)区水稻日照适宜度、降水适宜度与气候适宜度均呈下降趋势。分析淮河流域水稻温度、降水、日照和气候适宜度的区域差异,将淮河流域分为最适宜区、适宜性区、次适宜区。综合降水、日照、温度三因素,将淮河流域水稻气候适宜度分为分成淮北最适宜区、淮南最适宜区、淮河沿岸适宜区和西部山地次适宜区,分析各区水稻适宜度年际变化规律,结果表明:各区的水稻气候适宜度均呈逐渐下降趋势。  相似文献   

12.
长春地区稻田甲烷排放量的估算研究   总被引:7,自引:3,他引:4  
1995~ 1997年 3年的实验研究中 ,用静态箱法和气相色谱仪对长春地区不同水管理方式稻田的甲烷排放进行了采样和测量工作 ,1996年和 1997年逢晴天还同步进行了地面实验基地的卫星遥感数据 (TM和NOAA—AVHRR数据 )的接收工作。根据测算的稻田甲烷排放通量和用遥感数据提取的水稻种植面积 ,估算出区域尺度的稻田甲烷排放总量。 3年来的研究结果显示 ,长春地区水稻种植面积为 17.72 12× 10 4 hm2 ,稻田甲烷平均排放通量为 2 .984mg/(m2 ·h) ,长春地区稻田甲烷总排放量为 0 .0 2 0 3Tg/a。用灰关联方法分析了稻田甲烷排放的影响因子 ,建立了以水稻植被指数为参数的淹灌稻田的甲烷排放通量估算模型  相似文献   

13.
挠力河流域水稻生育期水分供需特征研究   总被引:1,自引:0,他引:1  
周浩  马泉来  邹朝晖 《地理科学》2021,41(3):534-543
基于MODIS遥感序列数据、常规气象数据、水稻生育期资料,利用区域遥感蒸散模型和水分盈亏评价模型,从栅格尺度揭示挠力河流域水稻生育期水分供需特征及水分盈亏状况。研究发现:① 全生育期的需水均值和降水均值分别为673.88 mm和291.81 mm,且各生育期的水分供需态势存在较大差异。中期的有效降水量与需水量分别占全生育期的42.25%和48.35%,而成熟期的有效降水量与需水量均偏低;② 水稻的缺水均值达到382.08 mm,空间上呈西、西北高而东、南、北端偏低的特点。全生育期和初期以轻度干旱为主,中期中度干旱区面积增加了10.68%,方向性极化特征突出,至成熟期缺水态势愈加严峻;③ 应依据不同生育期的水分供需特点来差别化灌溉水稻,对于中期和成熟期而言,应分别保证流域西北部和东南端的水稻用水需求。  相似文献   

14.
水稻施用硅肥研究综述   总被引:10,自引:0,他引:10  
文章首先综述了水稻施用硅肥后增产的机理,以及施用硅肥对水稻的叶片、植株、根系和抗逆性产生的积极影响,然后对水稻施用硅肥的增产效果以及增产幅度与土壤有效硅含量的关系作了总结,认为各地区施用硅肥的增产幅度存在差别,且北方一般高于南方;不同土壤类型,缺硅临界值应不同,并提出了华北平原的缺硅临界值为250mg/kg。最后,对今后的研究趋势作了论述。  相似文献   

15.
广州市跨国制造企业研发模式演变   总被引:1,自引:0,他引:1  
夏丽丽  林子棋 《热带地理》2014,34(2):191-198
跨国资本对发展中地区创新过程的影响已获得学术界高度关注,但对跨国资本在发展中地区研发模式的演变及其影响因素的研究仍然有限。通过半结构式问卷调研与深入访谈,对广州市跨国制造企业研发模式演变及引致其模式变迁的本土因素进行研究。结果表明:跨国制造企业研发模式的演变主要表现为本地研发人员比例逐步提高,开始构建包含本地创新主体在内的多渠道技术获取网络;调整新产品发布策略,加大对核心技术的保护;增加对研发资源的投入,“独立”和“辅助”母公司技术研发的职能显化,开始将本土企业纳入创新链条等。市场规模扩张、本土企业技术能力增加导致的市场推力和珠三角日益强化的资源、环境规制是引发跨国资本研发模式演变的主体因素。  相似文献   

16.
Rice planted in southern China accounts for 94% of the total in sown acreage and 88% of the total in production, which matters a lot to Chinese food security. However, due to the prolonged conflict between water availability and rice growth in spatial/temporal distribu-tion, rice production suffers from seasonal drought at acreage of 16%-22%, which compro-mises food production capacity and food security. Focusing on the spatial distribution of seasonal drought with rice and the practices to adapt to it, and based on an analysis of bal-anced water supply for and demand by rice at a growing season scale during 1981-2030, this paper assesses the changing seasonal drought in the process of rice production under the changing climate in the future, and identifies general rice re-cultivation options for climate change adaptation. Some conclusions can be drawn as follows. (1) Rice suggests a decline in seasonal drought, with early season rice (early rice hereafter) by 12,500 km2, middle season rice (middle rice) by 80,000 km2, and in particular late season rice (late rice) by 25,000 km2, which accounts for almost 20% of its cultivated acreage. It is indicated that due to climate change, seasonal drought in major rice producing areas tends to alleviate in general, late season rice in particular. (2) Future climate change brings about a significant impact on the spatial/temporal distribution of water resources in rice producing areas in China. Based on ’pre-designed’ adaptation actions for rice-re-cultivation, the rice cultivation pattern undergoes a significant alteration between 1981-2000 and 2001-2030. In eastern Guizhou and western Hunan, the pattern of single early plus single dry farming is changed into double cropping. In eastern Hunan, the pattern of dry cropping is changed into single early plus single dry farming. In northern Anhui, the pattern of dry farming cropping is changed into middle rice. All this is aimed at a potential adequate availability of water for rice production in the future. (3) Rice re-cultivation patterns developed in this paper help re-balance water demand and supply for rice growth using the spatial analysis tool to adapt rice growth to the changing water avail-ability from spatial perspective, and come up with rice producer-friendly re-cultivation options in response to climate change.  相似文献   

17.
In recent years, excessive levels of cadmium (Cd) in rice have been a focus of attention of the government, the public and scientists. In Guangzhou rice is a staple food for most citizens and understanding the level of Cd and other heavy metals in rice is important for food safety and health. Consumers in different income groups purchase rice from various sources at different prices but we know little about the relationship between price and safety. At the same time, the presence of zinc (Zn) can also affect the level of risk from Cd in rice and so affect food safety. This study offers a preliminary exploration of interactions between price, safety and nutritional quality. 125 rice samples were collected from markets and from the homes of high-income, middle-income and low-income groups in Guangzhou city, and were tested for the content of Cd and Zn. The results showed that 25.6% of the rice samples contained Cd in excess of the national standard, with higher levels of Cd in Indica rice than in Japonica. At the same time, we designed a questionnaire survey for groups with different incomes to assess their exposure to risks from rice with Cd and their perceptions and sources of information about risks. The survey showed that, as a whole, the low-income group faces higher risks from rice with Cd, and that there is strong public demand for scientific information about Cd in rice.  相似文献   

18.
水稻发育期模型研究进展   总被引:6,自引:1,他引:5  
张帅  陶福禄 《地理科学进展》2012,31(11):1485-1491
物候是气候变化的重要指示物.随着全球变化研究的开展,已经有越来越多的研究表明,随着气象条件的变化,植物的物候期发生了明显的变化,因此,对物候的精准模拟可以帮助我们准确理解作物对全球变化的响应机制,强大的物候模型已经逐渐成为提高植物对气候变化响应的模拟精度的一个关键工具.同时作物物候的模拟也是作物模型的一个重要组成部分.水稻是最重要的粮食作物之一,水稻发育期模型研究对水稻生长模型有着重要的意义.本文对国内外水稻发育模型的发展进行了综述,并提出了目前水稻发育期模型研究中存在的问题以及发展的方向,以期后续的水稻发育期模型乃至作物模型的研究提供借鉴.  相似文献   

19.
This paper examines the spatial characteristics of farmer/household behaviors in regional rice cropping systems (RCS), and the results provide necessary information for developing strategies that will maintain regional food security. Through field study and statistical analysis based on 402 households questionnaires finished in 2014-2015 in the Poyang Lake Region (PLR) of China, we arrived at two main conclusions. First, single- and double cropping rice were found across the study area, but showed a general distribution trend, with double cropping rice in the southeast part (especially in Jinxian county) and single cropping rice in the northwest (particularly in De’an county). Second, the household decisions concerning RCS varied in different parts of the PLR, but double cropping was the dominant type, with about 63.57% of the respondent households in the PLR cultivating double cropping rice. However, the multiple-cropping index of paddy rice was only 1.55. About 3% of interviewed households had altered their RCS during this period. Based on these findings, the local governments should guide farmers’ paddy field cultivation behaviors by increasing the comparative efficiency of rice production, promoting appropriate scale operations and land conversion, as well as optimizing rice growing conditions to improve the multiple cropping index and enhance food provision. Finally, land-use efficiency and more sustainable use of land resources should be improved.  相似文献   

20.
A survey was carried out at the largest rice cultivation area in Peninsular Malaysia,the Muda rice agroecosystem.The main objective of this study was to document the overall biodiversity associated with this unique agroecosystem by using a combination of sampling techniques in order to record different groups of fauna and flora.The total number of biota recorded and identified from the rice field ecosystem during the study period consisted of 46 species of zooplankton,81 species of aquatic insects,5 species of rodents,7 species of bats,87 species of birds,11 species of fishes and 58 species of weeds.A long-term study should be carried out as more species are expected to be recorded when more of the Muda rice agroecosystem area has been sampled to obtain sufficient information on the Muda rice agrobiodiversity.  相似文献   

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