关键词： 农业干旱   干旱影响强度   干旱成灾强度   气候变化  

摘要： 基于1951-2018年各省(自治区)农作物播种面积、干旱受灾面积、干旱成灾面积等数据,构建了干旱影响强度和干旱成灾强度特征指标,并分析近70a各省(自治区)空间尺度的农业干旱灾害的分布、发生次数、变化趋势和气候变暖背景下的阶段性变化特点。研究表明:(1)内蒙古自治区、山西省和河北省等省(自治区)的干旱受灾面积、干旱成灾面积、干旱影响强度和干旱成灾强度的多年平均值均位于前列;(2)中度及以上干旱等级发生次数最多的前10位均为北方省份(自治区),总次数均≥25次,其中内蒙古自治区、山西省和陕西省位居农业干旱发生次数最多前三位;(3)16省(自治区)的干旱受灾面积和干旱影响强度存在减小趋势,但大部分地区即23个省(自治区)的干旱成灾面积和27个省(自治区)的干旱成灾强度存在增加趋势;(4)受气候变化影响,各省(自治区)在气候较冷的I阶段(1951-1984年)农业干旱较轻,在气候增暖明显的II阶段(1985-1997年)农业干旱大幅加重,在气候增暖趋缓的III阶段(1998-2018年)农业干旱受灾面积、成灾面积和干旱影响强度普遍减小,但其成灾强度在加重。总之,农业干旱具有明显的南轻北重特征,且北方农业干旱更加频繁,因此北方地区仍需加强防御,减轻重大干旱对农业的影响。

关键词： 气候变化   气温   降水量   农业气象灾害   赣州市  

摘要： 统计江西省赣州地区2000-2019年的气温与降水量等气象观测资料,分析该地区气候变化特征,探析该地区主要农业气象灾害及防御措施,以期能够为合理利用当地气候资源、做好防灾减灾工作、保障当地民众日常生产生活安全等提供参考。

关键词： 吉林省和龙市   气候变化   农业生产  

摘要： 农业在我国国民经济发展中占有重要的基础地位,光、热、水是农作物生长发育过程中重要的气候资源,本文采用1990年~2019年吉林省和龙市气温、降水和日照时数观测资料,分析和龙市近30年的气候变化特征,结果表明,近30年来,和龙市年平均气温呈上升趋势,降水量呈波动减少的趋势,日照时数在作物生长期呈明显的上升趋势且年际变化大,气候变化的影响有利也有弊,利处是由于日照时数长、气温高,增加农作物生长期间的有效积温,满足农作物生长期间的热量条件,弊端是高温天气增多,降水年际分布不均,会形成旱涝灾害,影响农作物的生长发育。

关键词： Wetland   Climate change   Adaptation strategies   Economic-hydrological-behavioral modelling  

摘要： Water resources at the basin level are affected by climate change in the form of available water scarcity and multiple droughts leading to conflicts among different water users, especially between the agricultural sector and wetland services. However, owing to the multidimensional and multi-scalar nature of water management and climate change, it is needed to integrate tools to analyze impacts and adaptation. Accordingly, the current study presents an economic-hydrological-behavioral modeling to evaluate potential effects of climate change and adaptation strategies on irrigated agriculture and to manage water resources conflicts among different water users and uses in basins. This model has an iterative framework between a farm-based multi-objectives optimization model, a water evaluating and planning model (WEAP), and an agent-based model, which can represent socio-economic, hydrologic, agronomic and behavioral systems covering all dimensions and scales related to climate change. For this purpose, the economic-hydrological-behavioral modelling was applied in a case study in the Halilrud Basin in Kerman Province, Iran. Results revealed that adoption of suitable adaptive strategies and measures could mitigate the effects of climate change and provide more water to restore the Jazmourian Wetland in this basin. Additionally, the results indicated that different forms of rigidity in the individual behavior of farmers slowed down the adaptation of the agricultural sector, so that implementation of adaptive strategies led to only 14% less water consumption.

关键词： drought   climate change impacts   Titicaca basin   Andes   Altiplano  

摘要： The impact of climate change on droughts in the Lake Titicaca, Desaguadero River, and Lake Poopo basins (TDPS system) within the Altiplano region was evaluated by comparing projected 2034-2064 and observed 1984-2014 hydroclimate time series. The study used bias-corrected monthly climate projections from the fifth phase of the Coupled Model Intercomparison Project (CMIP5), under the Representative Concentration Pathway 8.5 (RCP8.5) emission scenarios. Meteorological, agricultural, and hydrological droughts were analyzed from the standardized precipitation, standardized soil moisture, and standardized runoff indices, respectively, the latter two estimated from a hydrological model. Under scenarios of mean temperature increases up to 3 degrees C and spatially diverse precipitation changes, our results indicate that meteorological, agricultural, and hydrological droughts will become more intense, frequent, and prolonged in most of the TDPS. A significant increase in the frequency of short-term agricultural and hydrological droughts (duration of 1-2 months) is also projected. The expected decline in annual rainfall and the larger evapotranspiration increase in the southern TDPS combine to yield larger projected rises in the frequency and intensity of agricultural and hydrological droughts in this region.

关键词： Climate change   Vulnerability   Agriculture and adaptation  

摘要： Climate variability and change pose ever-growing challenges in the semiarid tropics, where majority of the population depend on climate-dependent activities such as agriculture. This has rendered these countries more vulnerable to climate change-induced variability. In spite of the uncertainties about anticipated magnitude of climate change on regional scale, an assessment of the possible changes in key climatic elements to identify most vulnerable locations becomes important for formulating adaptation strategies. This study compiles the existing knowledge about observed climate and projections of future change in Telangana state of India. The agriculture in this semiarid state has to adapt to changes in mean climate variables to increased variability with greater risk of extreme weather events, such as prolonged dry spells. Based on climatic vulnerability assessment, we found that the number of vulnerable mandals (currently 28%) will be increased to 45% during early century and to 59% by mid-century. As per the climate exposure index scores, Jogulamba-Gadwal district was found to be most sensitive. Overall, vulnerability index scores indicated that Adilabad, Nagarkurnool, Nalgonda, Peddapalli, Suryapet, Wanaparthy, and Yadadri are extremely vulnerable districts in the state. The ranking of vulnerable mandals in each district envisages the need for a holistic approach for each mandal or a group of mandals to reduce their sensitivity though implementation of site-specific adaptation strategies to minimize climate-related shocks not only in agriculture but also in other sectors.

关键词： Climate variability   Crop production   Yields   Food security   Rain-fed  

摘要： Climate change and variability are a major threat to the agricultural sector globally. It is widely accepted that the changes in temperature, rainfall patterns, sea water level and concentration of CO(2)in the atmosphere will have the most devastating impacts on agricultural production. This paper examines the past and future crop production and food security in Kenya under variable climate. From the review, it is evident that the country is already experiencing episodes of climate change, manifested by seasonal changes in precipitation and temperature of varying severity and duration despite overreliance on rain-fed agriculture. The findings also reveal that climate change would continue to negatively affect crop production and food security to the already vulnerable communities in the arid and semi-arid areas. Future projections also indicate that climate variability will likely alter cropping patterns and yields in several regions. As the country is faced with a high population growth rate and rapid urbanization, crop production and food security systems need to become more adaptive as uncertainties of projected climate variability and change unfold. This study is important in providing decision makers and interested stakeholders with a detailed assessment of climate impacts and adaptation strategies geared towards improved crop production and food security.

关键词： Maharashtra   climate change   rainfall   temperature   agricultural crops   trends  

摘要： The present investigation attempts to understand the near-term (up to 2050) and distant (up to 2100) future climatic changes over Maharashtra. Trend analysis of projected monsoon rainfall and temperature was carried out with the use of parametric and non-parametric statistical techniques. All the meteorological sub-divisions in Maharashtra reveal a significant increase in monsoon rainfall during 2015-2100 (by 150-210 mm), except Konkan. In a near-term future, parts of the Vidarbha Sub-division and Western Ghats exhibit a significant increase in rainfall by 82-225 mm. Almost the entire state is very likely to experience a rise in annual mean temperature (AMT) by 0.5-2.5 degrees C up to 2050. The state is very likely to experience considerably warmer conditions post-2033. In particular, parts of Konkan and Madhya Maharashtra Sub-divisions will register significant warming (by 1-2.5 degrees C). The estimations also signify a marginal increase in AMT during the post-2070 period. The annual maximum temperature (AMXT) does not show a considerable rise;however, the annual minimum temperature (AMNT) is expected to increase (by < 1.2 degrees C) significantly over about 80% of the districts in Maharashtra. These climatic changes are very likely to affect the productivity of principal crops in Maharashtra including sorghum, pearl millet, sugarcane, wheat, rice and cotton. Under the future climate change scenario, therefore, it will be a great challenge for agronomist and policymakers to formulate a judicial plan for sustainable agriculture.

关键词： chill models   chill requirement   heat requirement   Prunus sp   spring frost risk   temperate trees   warm winters  

摘要： Winter chill is expected to decrease in many of the suitable growing regions for deciduous trees. Argentinean North Patagonia hosts extensive fruit tree cultivation, which provides an important contribution to both local and global food security. Using historic records from 11 weather stations from North Patagonia, we evaluate the possible impacts of climate change on fruit tree cultivation. We assess winter chill and seasonal heat availability, and the risk of spring frost events based on outputs from 15 Global Climate Models (GCMs) for two Representative Concentration Pathway (RCP) scenarios and two future time periods (represented by central years 2050 and 2085). Metrics were estimated for 47 years of records from the weather stations, as well as typical conditions for 10 past scenarios and 60 future GCM and RCP projections. Scenarios consisted of 100 plausible annual temperature records produced by a weather generator. Results suggest that fruit tree dormancy in Argentinean North Patagonia will not be strongly affected by climate change. Compared to the past, winter chill may only decrease by 9% in the RCP4.5 scenario by 2050 in the northeastern and eastern subregion, while in the central-south and west the reduction seems unlikely to exceed 6% by the same RCP scenario and year. Our models project stable high growing season heat in the northeastern and eastern regions, and major increases in the south by 2085 in both RCP scenarios. Projections of spring frost events varied between 0 and about 25 hours below 0 degrees C depending on the site. Increasing heat availability may create opportunities for fruit and nut growers to introduce new species and cultivars to the region. Our results provide a basis for planning such introductions and for enabling growers to exploit new opportunities for producing temperate orchard crops beyond their traditional ranges.