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1.
Abstract

Through a normative lens, this article investigates integrated ocean management and the multiple concepts that it involves. Although international law provides legal authority to coastal states to manage their ocean area entitlements, no single legally binding norm specific to integrated ocean management exists. Nevertheless, by combining different internationally recognized sources, this article identifies and discusses two normative concepts applicable in coastal state integrated ocean management. These are (1) the framing of integrated ocean management as a management process and (2) the incorporation of environmental, economic, and social concerns into an ocean management policy.  相似文献   

2.
烟草黑胫病综合防治研究进展   总被引:5,自引:0,他引:5  
烟草黑胫病是烟草上重要毁灭性病害之一。近年来,该病在我国大部分烟区发生普遍,造成的损失惨重,对烤烟的可持续发展构成严重的威胁。从农业防治、化学防治和生物防治等方面对烟草黑胫病的发生特点及其综合防治策略进行系统论述,以期为更好地防治该病奠定理论基础。  相似文献   

3.
Sunburn is a physiological disorder of apples and other fruit species caused by excess solar radiation. Damage occurs in practically all growing regions of the world, causing severe crop loss every year. Direct factors required for induction of the three currently-known types of sunburn (i.e., sunburn necrosis, sunburn browning, and photooxidative sunburn) include excess radiant heating and/or exposure to excess sunlight. Several other factors (e.g., relative humidity, wind velocity, acclimation of fruit, and cultural management practices), which alone cannot induce sunburn damage, indirectly influence the induction of sunburn by interacting with the direct factors to influence the appearance and severity of the symptoms. Sunburn affects apple fruit at many levels; it causes structural and morphological changes, alters pigment composition, influences adaptive mechanisms, impairs photosynthesis, and consequently decreases fruit quality. Fruits employ multiple physiological and biochemical mechanisms as complex defense systems to minimize damage. Photoprotective pigments, antioxidant enzymes and metabolites, heat-shock proteins, and the xanthophyll cycle help mitigate damage, but are often inadequate under field conditions to fully protect from sunburn. Quality loss significantly affects postharvest behavior, marketing and consumer acceptance of fruit. Internal fruit quality (e.g., firmness, soluble solids concentration, and titratable acidity) is affected by sunburn, and changes in these traits continue during cold storage. Sunburn-related disorders (e.g., sunburn scald in ‘Granny Smith’ and ‘Fuji’ stain) can appear in cold storage. There are several methods with various modes of action (e.g., climate ameliorating techniques, and sunburn suppressants) available to growers to decrease sunburn under field conditions. At the end of this review, the potential impact of a changing climate on sunburn incidence is considered, as both UV-B radiation and temperature are projected to change. Finally, several topics that need further research are discussed.  相似文献   

4.
The potential impact of climate change by the year 2050 on British grazing livestock systems is assessed through the use of simulation models of farming systems. The submodels, consisting of grass production, livestock feeding, livestock thermal balance, the thermal balance of naturally ventilated buildings and a stochastic weather generator, are described. These are integrated to form system models for sheep, beef calves and dairy cows. They are applied to scenarios representing eastern (dry) lowlands, western (wet) lowlands and uplands. The results show that such systems should be able to adapt to the expected climatic changes. There is likely to be a small increase in grass production, possibly allowing an increase in total productivity in some cases.  相似文献   

5.
Rice production is subject to increasing environmental and social constraints. Agricultural labor and water, which are key resources for rice production, illustrate this point. Nearly all rice-producing countries face reduced availability of agricultural water and shortage of farm labor. Plant pathologists should be concerned with such large-scale evolutions because these global drivers have an impact on not only the rice production system but also on the individual field and single-rice-plant levels. These concerns are closely associated with the long-term sustainability and environmental consequences of the intensification of agricultural systems brought about by problems of feeding a rapidly growing human population. Furthermore, genetic diversity in rice production has been reduced, thus inducing frequent disease epidemics and pest outbreaks. Looking ahead, we need to realize the need to maintain the diversity and yet retain the high productivity of the system. Natural resources, including genetic resources, are not infinitely abundant. We have to be efficient in utilizing genetic resources to develop durable resistance to rice diseases. Developing resistance is an important first step in tackling the disease problem, but it is not the only step available to achieve durability. Deployment of resistance must be considered in conjunction with development of host plant resistance. To attain durability, we need a better understanding of the coevolution process between the pathogen and the host resistance gene. Our target is an integrated gene management approach for better disease control and more effective utilization of genetic resources. Plant pathology, as an applied science, derives its strengths from various disciplines. To do the job right, we need a better understanding of the pathosystems, the epidemiology, and the coevolution process between the pathogen and the host resistance gene. The challenge, as pointed out by pioneers in our profession, is to prove the usefulness and the relevance of our research. Thus, we need to strike a balance between mission-oriented and fundamental research and make sure that our profession is (still) useful in the information technology and genomic era. We believe that a gene-based and a resource-based disease management approach should allow us to incorporate these new scientific developments. However, we do need to incorporate the new science for fundamental research to solve practical problems of rice production.  相似文献   

6.
气候变化背景下东北水稻的时空分布特征   总被引:3,自引:0,他引:3  
以受气候变化影响显著的中国东北地区(黑龙江、吉林和辽宁)为研究区域,以水稻为研究对象,利用1980—2010年东北三省分县水稻播种面积、水田分布以及水稻气候适宜性分布等多源数据,结合作物空间分配模型(SPAM),在5′×5′的像元尺度上模拟了东北地区水稻时空变化过程,结合气温、降水等气候因子的空间分异,重点分析了水稻分布在不同积温与降水区间的时空变化特征.结果表明: 水稻分布的核心纬度由北纬39°—46°推移至41°—47°,经度则由122°—127°向东推移至131°,同时还呈现向200 m以上的较高海拔地区扩展的趋势;区域内积温带均向北偏移,新增的水稻面积主要集中在2800~3400 ℃·d的积温区间;研究期间区域内降水量2000年以前呈增加趋势,之后下降,水稻面积变化则主要发生于300~600 mm的降水区间内.  相似文献   

7.
沙田柚的主要病虫害及其综合治理   总被引:5,自引:0,他引:5  
介绍沙田柚优质高产栽培管理中的主要病虫害发生的特点,及其综合治理原理与技术措施.  相似文献   

8.
Rice panicle blast is one of the most serious diseases threatening stable rice production by causing severe damage to rice yields and quality. The disease is easy to occur under low air temperature and frequent heavy rainfall during the heading season of rice. In 2021, a rice panicle blast severely occurred in the Jeonbuk province of Korea. The incidence area of panicle blast accounted for 27.7% of the rice cultivation area of Jeonbuk province in 2021, which was 13.7-times higher than in 2019 and 2.6-times higher than in 2020. This study evaluated the incidence areas of rice panicle blast in each region of Jeonbuk province in 2021. The weather conditions during the heading season of rice, mainly cultivated rice cultivars, and the race diversity of the Jeonbuk isolates were also investigated. It will provide important information for the effective control of the rice panicle blast.  相似文献   

9.
Salt Lakes in Australia: Present Problems and Prognosis for the Future   总被引:4,自引:4,他引:0  
Australia is a land of salt lakes and despite low human population density, many lakes are adversely impacted by a range of factors. Secondary salinisation is the most pernicious force degrading lakes, especially in south-west Western Australia where up to 30% of the landscape is predicted to be affected. Mining also impinges on many salt lakes in this state, mainly through the dewatering of saline groundwater. Exploitation of groundwater for irrigation caused some lakes in Victoria, Australia, to dry, especially the significant Red Rock Complex. Global climate change will result in new water balances in endorheic lakes, with most having less water, particularly the seasonal lakes of southern Australia. This has already happened in Lake Corangamite, Victoria, but the prime reason is diversion of inflowing floodwater. Consequently, the lake has retreated and become salinised compromising its status as a Ramsar site. Various other lakes suffer from enhanced sedimentation, have introduced biota or their catchments are being disturbed to their detriment. Enlightened management should be able to maintain some important lakes in an acceptable condition, but, for most others, the future is bleak.  相似文献   

10.
Rice blast is the most destructive disease threatening stable rice production in rice-growing areas. Cultivation of disease-resistant rice cultivars is the most effective way to control rice blast disease. However, the rice blast resistance is easy to breakdown within years by blast fungus that continually changes to adapt to new cultivars. Therefore, it is important to continuously monitor the incidence of rice blast disease and race differentiation of rice blast fungus in fields. In 2020, a severe rice blast disease occurred nationwide in Korea. We evaluated the incidence of rice blast disease in Yeoju and compared the weather conditions at the periods of rice blast disease in 2019 and 2020. We investigated the races and avirulence genes of rice blast isolates in Yeoju to identify race diversity and genetic characteristics of the isolates. This study will provide empirical support for rice blast control and the breeding of blastresistant rice cultivars.  相似文献   

11.
When Trichoderma harzianum and Aspergillus niger, as biocontrol agents, were included with two fungicides, Foltaf 80W (Captafol 80%) and Blue Copper-50, for the treatment of pigeon-pea wilt, the disease was more effectively controlled than when the fungicides were used alone. Accordingly, decreased amounts of the fungicides could be used to control the disease without adversely affecting the growth of pigeon-pea.  相似文献   

12.
In 1969, Paton and Vizi (1) described the inhibitory actions of noradrenaline on acetylcholine release from the innervation of the guinea-pig ileum longitudinal muscle. They concluded that acetylcholine output by the nervous networks of the longitudinal strip is under the normal control of the sympathetic by a species of presynaptic inhibition mediated by receptors. This work was carried out in the Pharmacology Department at Oxford University. Clearly, a period in the Dreaming Spires of Oxford sufficiently inspired Sylvester to take up a life long career in scientific research. He has published more than 300 papers on a wide range of topics but clearly has a strong interest in neurotransmitter release mechanisms and recently, non-synaptic interactions between neurons. It seems fitting therefore to write a brief review on the continuing studies on neurotransmitter release mechanisms in sympathetic neurons in a volume honoring the now distinguished Professor Vizi.  相似文献   

13.
淮河流域双季稻气候适宜度及其变化趋势   总被引:13,自引:0,他引:13  
选取淮河流域33个县市1961-2005年的逐日气象数据,运用模糊数学和空间插值方法,对淮河流域双季稻的温度、降水、日照和气候适宜度进行了研究.结果表明:温度和降水是淮河流域双季稻生长的关键气候因子,早、晚稻各气候因子适宜度地域差异明显;其中,早稻气候适宜度由中部平原向东部沿海和西部山区递减,晚稻气候适宜度由南向北递减;温度适宜度以0.01(10a)~(-1)的速率上升,说明温度对淮河流域水稻生长发育产生正效应;日照适宜度以>0.02(10a)~(-1)的速率下降,总的气候适宜度呈下降趋势.
Abstract:
Based on the 1961-2005 meteorological data from thirty three stations in Huaihe River basin, and by using fuzzy mathematics and spatial interpolation methods, the climate suitability of double-cropping rice in this basin were studied. Temperature and precipitation were the key climate factors affecting the growth of double-cropping rice, and the climate suitability of both early-and late rice had strong regional characters. The climate suitability of early rice decreased from central plain area to east coast and west mountain area, whereas that of late rice decreased from south area to north area. Temperature suitability increased at a rate of 0. 01 (10a)~(-1), sug-gesting that temperature had positive effects on the growth and development of double-cropping rice in Huaihe River Basin. Sunlight suitability decreased at a rate higher than 0. 02 (10a)~(-1).The overall climate suitability had a decreasing trend.  相似文献   

14.
李海东  高吉喜 《生态学报》2020,40(11):3844-3850
应对气候变化和保护生物多样性是2大全球性热点环境问题。气候变化导致物种多样性丧失、生态系统服务降低和区域生态安全屏障功能受损,威胁到中国国土生态安全格局和生态脆弱区域的可持续发展,给生物多样性保护带来新的挑战。做好生物多样性保护适应气候变化的风险管理工作,既是生物多样性应对气候变化风险的必要措施,也是减缓气候变化的重要途径。结合爱知目标10的实现情况,分析了欧盟、澳大利亚、美国等发达国家发布的生物多样性适应气候变化技术政策制定情况、中国生物多样性应对气候变化进展情况,剖析了中国生物多样性保护适应气候变化存在的问题,包括生物多样性应对气候变化的科学认知亟待提高、生物多样性保护适应气候变化的能力建设不足、自然保护地之间缺乏适应气候变化的生态廊道网络、生物多样性保护适应气候变化的技术标准缺乏。研究提出了中国生物多样性应对气候变化的适应性管理策略,包括制定《中国生物多样性保护协同应对气候变化的国家方案》、加强生物多样性保护适应气候变化的能力建设、开展自然保护区适应气候变化的风险管理试点、强化生物多样性应对气候变化的科技支撑,以期为推进纳入气候变化风险管理的生物多样性保护工作提供决策依据。  相似文献   

15.
The African citrus triozid (ACT), Trioza erytreae Del Guercio, is a destructive pest particularly on citrus, and vectors, “Candidatus” Liberibacter africanus (CLaf), which is the causal agent of the African citrus greening disease. Our study seeks to establish the distribution and host‐plant relationship of ACT across citrus production areas in Kenya. We also modelled the risk of spread using the maximum entropy modelling algorithm with known occurrence data. Our results infer that ACT is widely distributed and causes severe damage to four alternative host plants belonging to the family Rutaceae. The adults, immature stages (eggs and nymphs), galls and the percentage of infested leaves were significantly higher in shaded than unshaded trees. However, adult ACTs preferred Kenyan highlands to Victoria Lake and coastal regions. The average area under the curve of the model predictions was 0.97, indicating an optimal model performance. The environmental variables that most influenced the prediction were the precipitation of wettest quarter, precipitation of wettest month, mean diurnal range, temperature seasonality and mean temperature of the coldest quarter. The current prediction of ACT exceeded its existing range, especially in the Western, Nyanza, Central, Rift valley and Eastern regions of Kenya. The model predicted a contraction of suitable habitats for a potential spread in 2040 with an inland shift to higher altitudes in the cooler regions. The potential for further expansion to climatically suitable areas was more pronounced for the 2080 forecast. These findings provide relevant information to improve monitoring/surveillance and designing IPM strategies to limit its spread and damage.  相似文献   

16.
中国水稻生产对历史气候变化的敏感性和脆弱性   总被引:9,自引:0,他引:9  
熊伟  杨婕  吴文斌  黄丹丹  曹阳 《生态学报》2013,33(2):509-518
有效的适应措施需要了解两类基础信息,一是农业生产所面临的各种气候变异风险,二是作物产量对潜在气候变异风险的反应及其机制.评价作物生产对历史气候变化的敏感性和脆弱性,可以在时间上和空间上揭示气候变化的趋势及作物产量对其的反应,从而为适应行动的全面开展提供基础信息.通过分析1981-2007年水稻生育期3个气候因子(平均温度、日较差、辐射)的变化对水稻产量的影响,评估我国水稻生产对这3个气候因子变化的敏感性和脆弱性及其区域分布状况.结果表明,1981-2007年间我国大部分水稻产区生育期内3个气候因子均发生了明显变化,存在着气候变异风险,其中以最高温的变化最普遍和明显,导致水稻生产中高温热害风险增加.部分区域水稻产量变化与单一气象因子的变化存在着显著的线性相关,这些地区气候因子的变化可以一定程度地解释水稻产量变化趋势,其中产量变化对辐射变化最敏感.当水稻生育期内平均温度上升1℃、日较差升高1℃、辐射下降10%时,我国部分地区水稻产量随之发生了相应的变化,其中辐射降低导致我国水稻生产的脆弱面积最大,其次为日较差.受3种气象因子变化趋势的综合影响,约有30%的水稻产区对1981-2007年的气候变化趋势敏感,少部分地区表现为脆弱,但水稻主产区受到的影响不大,且在东北地区还集中表现出产量增加的趋势,为我国水稻发展提供了契机.  相似文献   

17.
Flowering onset has attracted much attention in ecological research as an important indicator of climate change. Generally, warmer temperatures advance flowering onset. The effect of climate warming on flowering onset is more pronounced in spring because the difference between atmospheric and water temperatures creates more rapid convection than in other seasons. We analyzed the correlation between 73 species of spring woody plants in Hongneung Arboretum in Seoul, South Korea and the spring minimum temperature and average precipitation over the past 50 years (1968–2018). The spring minimum temperature and average precipitation have increased over the past 50 years, resulting in the advance of the first flowing date (FFD) in all 73 species by 8.5 days on average. A comparison of FFD changes over time by dividing the survey period into three time periods confirmed the advance of the FFD in 50 species (68% of investigated species) by 11.1 days on average in both Period 2 (1999–2008) and Period 3 (2009–2018) relative to Period 1 (1968–1975). Additionally, a delay of the FFD by 3.2 days on average was observed in 8 species. The FFD of Lonicera chrysantha (Caprifoliaceae) advanced by over 40 days and was highly correlated with the increased spring minimum temperature. Analysis of the sensitivity of plant responses to climate change revealed that a temperature rise of 1°C was associated with an FFD advance of 1.2 days in all species. The species that was most sensitive to temperature change was Spiraea pubescens for. leiocarpa (Rosaceae), whose FFD advanced by 4.7 days per 1°C temperature rise. Each increase in precipitation by 1 mm was found to result in a 0.1-day advance of the FFD of all species. Prunus tomentosa (Rosaceae) was the most sensitive species, that advanced by 2.6 days for each 1 mm increase in precipitation. Thus, for all species, the FFD was more sensitive to the change in temperature than in precipitation. Assuming that the current greenhouse gas (GHGs) emission levels or atmospheric CO2 concentration is maintained, Seoul’s spring minimum temperature is projected to rise by 2.7°C over the next 50 years. Accordingly, considering only the global temperature change, the mean FFD of the study’s 73 species is projected to advance by an additional 3.4 days.  相似文献   

18.
The Tongass National Forest (Tongass) is the largest national forest and largest area of old-growth forest in the United States. Spatial geographic information system data for the Tongass were combined with forest inventory data to estimate and map total carbon stock in the Tongass; the result was 2.8 ± 0.5 Pg C, or 8% of the total carbon in the forests of the conterminous USA and 0.25% of the carbon in global forest vegetation and soils. Cumulative net carbon loss from the Tongass due to management of the forest for the period 1900–95 was estimated at 6.4–17.2 Tg C. Using our spatially explicit data for carbon stock and net flux, we modeled the potential effect of five management regimes on future net carbon flux. Estimates of net carbon flux were sensitive to projections of the rate of carbon accumulation in second-growth forests and to the amount of carbon left in standing biomass after harvest. Projections of net carbon flux in the Tongass range from 0.33 Tg C annual sequestration to 2.3 Tg C annual emission for the period 1995–2095. For the period 1995–2195, net flux estimates range from 0.19 Tg C annual sequestration to 1.6 Tg C annual emission. If all timber harvesting in the Tongass were halted from 1995 to 2095, the economic value of the net carbon sequestered during the 100-year hiatus, assuming $20/Mg C, would be $4 to $7 million/y (1995 US dollars). If a prohibition on logging were extended to 2195, the annual economic value of the carbon sequestered would be largely unaffected ($3 to $6 million/y). The potential annual economic value of carbon sequestration with management maximizing carbon storage in the Tongass is comparable to revenue from annual timber sales historically authorized for the forest.  相似文献   

19.
I am honored to receive the second Lifetime Achievement Award by International Workshops on Opportunistic Protists and to give this lecture. My research involves Pneumocystis, an opportunistic pulmonary fungus that is a major cause of pneumonia (“PcP”) in the immunocompromised host. I decided to focus on Pneumocystis ecology here because it has not attracted much interest. Pneumocystis infection is acquired by inhalation, and the cyst stage appears to be the infective form. Several fungal lung infections, such as coccidiomycosis, are not communicable, but occur by inhaling < 5 μm spores from environmental sources (buildings, parks), and can be affected by environmental factors. PcP risk factors include environmental constituents (temperature, humidity, SO2, CO) and outdoor activities (camping). Clusters of PcP have occurred, but no environmental source has been found. Pneumocystis is communicable and outbreaks of PcP, especially in renal transplant patients, are an ongoing problem. Recent evidence suggests that most viable Pneumocystis organisms detected in the air are confined to a patient's room. Further efforts are needed to define the risk of Pneumocystis transmission in health care facilities; to develop more robust preventive measures; and to characterize the effects of climatological and air pollutant factors on Pneumocystis transmission in animal models similar to those used for respiratory viruses.  相似文献   

20.
The simulation model LSTSIM was revised and adapted to estimate the effects of different management strategies on populations of the lone star tick, Amblyomma americanum (Linnaeus), in non-agricultural areas. The control technologies evaluated were area-wide acaricide application, acaricide self-treatment of white-tailed deer, vegetation reduction and reductions in the density of white-tailed deer. Estimated changes in tick populations using these technologies compared favorably with results from actual integrated tick management studies at five different geographic locations. Area-wide acaricide application and vegetation reduction, as well as combinations of the two technologies proved to be useful for short-term, seasonal management of ticks in small non-agricultural areas and residential sites. Self-treatment of deer with acaricide, applied topically or as a systemic, appears to be the most cost-effective technology for use in area-wide, long-term programs for tick control. The results of simulations suggest that reductions in deer density should be considered as a component of any tick management program.  相似文献   

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