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1.
Biola K. Badmos Grace B. Villamor Sampson K. Agodzo Samuel N. Odai Olabisi S. Badmos 《Singapore journal of tropical geography》2021,42(1):65-84
In this study, the Land Use Dynamic Simulator model was applied to investigate the impact of farm credit as an adaptation strategy to cope with effects of climate variability on agricultural land‐use change and crop production in the Vea watershed in Ghana. The authors identified the determinants of crop choices within the landscape (e.g., farm household and biophysical characteristics of farm plot). The crop choice sub‐model was then linked to the crop yield sub‐model to determine the yields of selected crops. In adapting to the impacts of climate variability, the maize credit adoption sub‐model under the maize cultivation credit scenario was integrated into decision‐making. This was simulated for a 20‐year period, and compared with the business‐as‐usual scenario. Under the simulated maize credit scenario, maize adopters increased from about 20 per cent to about 50 per cent and the area allocated for maize cultivation significantly increased by about 266 per cent. Consequently, the average annual aggregated household crop yield increased by 6.3 per cent higher than in the business‐as‐usual scenario. This simulation study shows that access to maize credit can significantly influence agricultural land‐use change and food availability in the study area. However, although access to farm credit may translate into food availability, the sustainability of this strategy is questionable. 相似文献
2.
本文以广东省４７个测站近４０年来６～９月降水量、平均气温、总日照时数和一些主要农作物逐年单产量资料为基础，用主分量分析、周期回归等方法，分析广东全省性的气候时空变化特征；分析一些主要农作物逐年单产的变化规律．用多元逐步回归分析方法探讨了广东全省性气候变化与同期及后期（１～３年）主要农作物单产量间的关系并作了预报． 相似文献
3.
西北地区气候暖干化对作物气候生态适应性的影响 总被引：12，自引：1，他引：11
在综述西北地区现代气候变化基本特征是暖干化的基础上,重点揭示了冬小麦、春小麦 (夏粮)、玉米、马铃薯、谷子、糜子（秋粮）和棉花、胡麻、冬油菜、酿酒葡萄（经济作物）等10种主要作物的热量指标、水分指标和生长发育状况等对现代气候暖干化的响应特征。气候变暖对作物热量生态适应性的影响非常显著,作物需要热量指标比变暖前有提高的趋势;气候变干对作物水分生态适应性的影响非常敏感,作物需要水分指标比变干前有增多的趋势。气候暖干化对作物气候生态适应性的影响总体来说是利弊并重。对灌溉区作物是利多弊少,建议要创建干旱区现代农业发展模式来应对;对旱作区作物是弊远大于利,建议要建立一整套旱作农业生产机制来适应气候暖干化。提出了作物气候生态适宜度是气候暖干化对作物产生重大影响的重要原因。 相似文献
4.
本文根据晋中五大盆地的热量、水量实测数据和当地的实际情况,分析计算了不同耕作制度下主要作物农田热量盈亏量和无灌溉条件下的水量盈亏量。为充分合理利用水热资源,发展农业生产,提供科学依据。 相似文献
5.
Cynthia Rosenzweig 《The Professional geographer》1990,42(1):20-37
This study utilizes global climate models and crop growth models to estimate the potential agricultural effects of climate change caused by a doubling of atmospheric carbon dioxide for the southern Great Plains. Projected climate changes cause simulated wheat and corn yields to decrease in the study area. Decreases in modeled grain yields are caused primarily by temperature increases which shorten the duration of crop life cycle and curtail the harvestable biomass production. While physiological effects of carbon dioxide and changing cultivars offer some hope of climate change mitigation, detrimental consequences to regional crop production, including need for increased irrigation, are suggested. 相似文献
6.
中原腹地气候变化对冬小麦产量的影响——以商丘地区为例 总被引：7，自引：2，他引：5
为探明气候变化对商丘地区冬小麦产量的影响,根据1991～2010商丘市气候资料和小麦产量资料,利用数学统计与Thornthwaite Memoriae模型,结合未来气候预测结果定量分析了气候变化对冬小麦产量的影响。结果表明,冬小麦产量整体上呈波动上升趋势;主成分分析表明,气温、降水量、蒸发量与极端温度为影响冬小麦产量的主要气候因子,蒸发量过大及极端低温对冬小麦生产不利。商丘地区"暖湿型"气候有利于冬小麦生产力的提高,"冷干型"气候对冬小麦生产最为不利;未来几十年内气候可能将向"暖湿型"变化,对商丘地区粮食作物产量的提升较为有利。 相似文献
7.
中国粮食生产的综合影响因素分析 总被引：18，自引：1，他引：17
采用模型模拟的方式, 根据中国社会发展规划, 将未来社会经济发展情景与区域气候模型、水资源模型和作物模型相连接, 综合评估和分析未来中国的粮食生产状况, 以期为宏观决策提供科学参考。结果表明, ①气候变化将影响未来三大作物单产, 如果不考虑 CO2 肥效作用, 未来雨养作物单产将受到更大冲击; 当灌溉条件保障后, 水稻受到冲击更大, 单产降低最多, 尤其是 A2 情景。如果考虑 CO2 肥效作用, 未来玉米平均单产变化不大, 小麦单产明显增加, 尤其是雨养小麦, 水稻单产也有所增加。②未来气候变化、水资源、社会经济发展将影响中国三大作物的需水量和农业供水量, 导致水稻、灌溉玉米和小麦的播种面积下降, 而雨养小麦和玉米的播种面积上升。③未来气候变化、 CO2 肥效、水资源和土地利用变化对粮食生产的影响较为复杂, 依情景和时段的不同而不同。农业可用水资源对粮食总产的影响最不利, 致使三大作物粮食总产量明显降低, 成为未来粮食生产的主要限制因素, 尤其是水稻生产; 土地利用对总产的负面影响最小; 气候变化和 CO2 的相互作用可使总量少许增加。未来各情景下水稻受到冲击最大, 而小麦和玉米则表现为不同程度的增产。 相似文献
8.
RELATION BETWEEN VEGETATION CHANGES, CLIMATE VARIABLES AND LAND-USE POLICY IN SHAANXI PROVINCE, CHINA 总被引：1，自引：0，他引：1
MADELENE OSTWALD ELISABETH SIMELTON DELIANG CHEN ANLIN LIU 《Geografiska Annaler: Series A, Physical Geography》2007,89(4):223-236
Shaanxi Province in China has been exposed to climate variability and dramatic land‐use policies. The aim here is to examine vegetation changes in this area on a regional scale from 2000 to 2004 in relation to land‐use changes and climate traits. The data in this assessment include remote sensing information from moderate‐resolution imaging spectro‐radiometer normalized difference vegetation index from 2000 to 2004, and climate data (precipitation and temperature) from 1956 to 2000. The results show an increase in vegetation production from 2000 to 2004, particularly in the north, which cannot be explained solely by climate impacts. Since the vegetation in the north is more dependent on climate variation than the other parts of Shaanxi due to more serious water limitation, the results suggest that the large‐scale land‐use policy implemented over the last decade, with a focus on northern Shaanxi, is possibly having an impact on the overall vegetation. 相似文献
9.
Kent M. McGregor 《自然地理学》2013,34(6):551-565
Most scenarios of greenhouse-gas climatic change predict a warmer drier Great Plains environment. The goal of this research was to determine the resulting change in soil moisture and to relate this to changes in agricultural productivity. Soil moisture was used in regression-based models to predict yields for the four major grain crops: wheat, corn, soybeans, and grain sorghum. The results indicate that a warmer drier climate would reduce yields for the summer crops throughout the state. The yield for winter wheat also decreased in the western part of the state but actually increased in eastern Kansas. Corn and soybeans could decline in the dry land crop mix in eastern Kansas as wheat becomes a more viable alternative. Thus, the results imply possible geographic shifts in the crop belts in Kansas. [Key words: climatic change, agricultural production, soil moisture.] 相似文献
10.
Rice is the main food crop in densely populated Bangladesh. Regional climatic variations can play an important role in rice productivity. For example, excessive heat or extremely cool conditions disrupt normal plant physiological processes and cause plant injury which, in turn, results in reduction of yield. In this study, the climatic crop productivity model YIELD has been applied to calculate rice productivity for the boro rice growing season (December/January-May) in Bangladesh under changing climatic conditions. The model estimates climatic influences on various rice plant-growth parameters. YIELD was tuned and validated to Bangladesh's environment to represent appropriate agroecological conditions. The model was run using long-term average climate data of 12 meteorological stations located in the major rice-growing regions in Bangladesh to establish baseline estimates of yield. For the climate change study, 20 scenarios were created by synthetically fluctuating thermal and solar climates in Bangladesh. Study results show that per 1° C increase in growing season mean air temperature, boro rice yield was reduced by 4.6%. It was also found that each 10% increase in incident solar radiation resulted in a 6.5% increase of boro rice yield in Bangladesh. 相似文献
11.
Munang Tingem Mike Rivington Jeremy Colls 《Singapore journal of tropical geography》2008,29(3):357-370
The effects of interyear variability of extreme rainfall events on maize yields at locations in Cameroon, in central‐west sub‐Saharan Africa were investigated through a simulation assessment combining a weather generator with a crop growth model. This study analyzes the potential of using dry/wet year predictions to reduce risk in subsistence agricultural production associated with climate variability at the site level. Weather data sets from eight provincial study localities were classified into three precipitation scenarios – dry (lower threshold), normal and wet (upper threshold) years. According to the modelling results, there is a less than 12 per cent variance in mean maize yields across six out of the eight localities when planting occurs in March, May and August. The variance is equivalent to approximately 100–300 kg per ha, which represents a significant amount of food in the household security of the majority impoverished sectors of rural and urban society, and which could greatly impact the socioeconomic activities of the entire populace. The results lead to the conclusion that all extreme dry and wet years are not equal in terms of their regional manifestation. This calls for precise monthly and sub‐seasonal local level forecasts and the effective dissemination of this information to farming communities in Cameroon, thereby facilitating the adaptive management of indigenous cropping practices and reducing their vulnerability to climate related disasters. 相似文献
12.
13.
1IntroductionTheconventionalassessmentSonthepossibleimPactsofclilnateAngehaveahrpothesisofkeepingclimaticvariabilityinaccordtviththatofpresentclimateduetolackofavailableinformationchangesinclimaticvariabiiltyFixedtemperaturechangeandfixedprecipitationadjustingfactorsassumedorderivedffomGCMs'shoulahonareaddedtotheobserveddailytemperatUrormulhpliedwithhiStoricaldailypreeipitahonrespechvelyinthesestUdiest11.Alti1oughthereareanUInerofapparentdeficienciesinGCMs,includinglowertemporalandspatia… 相似文献
14.
Katherine Klink 《自然地理学》2013,34(4):289-314
Increased interest in climate change at local and regional scales has prompted climate simulations for regional areas, but tests of climate models have not specifically examined the impacts of regional heterogeneity, and they have largely overlooked possible temporal sensitivity. In this study I used a coupled surface-atmosphere mesoscale model to evaluate the effects of regional heterogeneity in five land-surface parameters that have the strongest impacts on the surface energy balance: albedo, roughness, canopy resistance, rooting profile, and soil water content. I included temporal variability in climate sensitivity by completing a series of mid-month simulations representative of the June-September growing season. I modeled land surfaces of maize contrasted with bare soil, grass, or coniferous trees. Roughness discontinuities were important factors in determining regional energy balance and surface temperature for all three surface contrasts. The effects varied over the growing season as a function of maize height. Canopy resistance was equally important, especially during the middle of the season when the maize canopy was at its fullest extent. Albedo effects appeared to be secondary, but often were more important in September. Changes in soil water content had little impact because vegetation in these simulations was not stressed by low soil moisture. The importance of roots in these simulations was primarily a function of their presence or absence, rather than of the specific profile assigned to each vegetation type. Roughness and canopy resistance discontinuities appeared to play the largest role in determining the regional average energy balance and surface temperature for growing season dates. [Key words: land-surface heterogeneity, energy balance, climatology.] 相似文献
15.
CAMILLA S. ANDRESEN SVANTE BJORCK 《Geografiska Annaler: Series A, Physical Geography》2005,87(1):159-174
ABSTRACT. Two well dated Holocene sediment records bordering the Denmark Strait region have been used to reconstruct past climate variability. The content of biogenic silica, classic and organic material and moss in a lacustrine record from Lake N14 has been used to infer past variability in precipitation and temperature in southern Greenland. Sedimentologic and petrologic composition of sand in a shelf sediment record from the Djúpáll trough is used to infer past variability in the northwestern storm activity on northwestern Iceland, which probably also affected the inflow of polar waters from the East Greenland Current. Our evaluation of these records with a number of previous studies from the region documents Holocene climatic optimum conditions peaking between 8000 and 6500 calendar years before present (cal yr BP). Mid-Holocene climate deterioration set in around 5000 cal yr BP followed by a further marked setback around 3500 cal yr BP. A stacking of climate variability on a centennial timescale from previous studies in the area shows a fairly good correspondence to the timing of marked cold and warm events as evidenced from the Lake N14 and the Djúpáll trough records. Cooler periods are explained as the response to marked incursions of ice-laden polar water from the Arctic Ocean to the Denmark Strait region. Cool northerly and northwesterly winds along the East Greenland coast in relation to frequent strong atmospheric low pressure in the Barents Sea, coupled with strong high pressure over Greenland, would have favoured southward export of polar waters. A comparison with the proxy records of nuclide production (14 C and 10 Be) suggests that solar activity may have had some influence on the atmospheric pressure distribution in the Denmark Strait region. 相似文献
16.
中国作物物候对气候变化的响应与适应研究进展 总被引：5，自引：2，他引：5
以气候变暖为主要特征的气候变化对作物物候产生了重要的影响,通常气温升高会导致作物生长速度加快,生育期缩短,从而造成作物产量下降,不利于农业发展。同时,作物物候变化可以直接或间接反映气候变化情况,对于气候变化具有重要的指示意义。作物物候的研究对于农业气象灾害的预防、农业生产管理水平的进步以及农业产量提高都极为关键。随着全球地表气温的持续升高,作物物候相关研究也越来越引起科学家的关注。论文结合作物物候的主要研究方法,综述了中国近几十年来小麦、玉米、水稻以及棉花、大豆等主要农作物的生育期变化特征以及主要的驱动因子,得到以下主要结论：①在研究方法上,统计分析方法应用最为普遍,其他几种方法都需要与统计分析方法相结合使用。另外,作物机理模型模拟方法易于操作、可行性强,在物候研究中应用也比较多。遥感反演方法对作物生育期的特征规律要求较高,一般主要关注作物返青期。②整体上,小麦全生育期主要呈缩短趋势,而玉米和水稻全生育期以延长趋势为主。③作物物候变化的驱动因子主要是气候变化和农业管理措施改变,其中,气候变化是主导驱动因子,对作物物候变化起决定作用,而调整农业管理措施,在一定程度上抵消气候变化对作物生育期的不利影响。作物物候对气候变化的响应和适应研究可以为农业生产适应气候变化提供重要的理论依据和对策。 相似文献
17.
CONTRASTING TREE‐RING GROWTH RESPONSE OF PICEA ABIES TO CLIMATE VARIABILITY IN WESTERN AND EASTERN ESTONIA 
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下载免费PDF全文 SAMULI HELAMA ALAR LÄÄNELAID SZYMON BIJAK JAAK JAAGUS 《Geografiska Annaler: Series A, Physical Geography》2016,98(2):155-167
Climatic variations and changes regulate arboreal growth. In Estonia, the tree‐ring growth variability of coniferous and deciduous trees has been linked with various climatic variables in different parts of the country. However, the dendroclimatic signals of Norway spruce (Picea abies (L.) H.Karst.) have not been explored across the region. Here we compare the growth variability of this species, growing under various site conditions in Estonia, with records of temperature, precipitation, and indices of the North Atlantic Oscillation over a period of 50 years (1956–2005). Western chronologies correlated positively and significantly (p<0.01) with early‐summer (June) precipitation, while eastern chronologies showed positive and significant (p<0.05) correlation with mid‐winter (January) precipitation. Moreover, the eastern chronologies correlated positively and significantly (p<0.05) with the North Atlantic Oscillation index in January. First, our results indicated that the previously established geobotanical division, rather than forest site types, most probably explains the spatial patterns in spruce growth variability. Second, our findings agreed with the late Quaternary pollen studies showing that the vigour of spruce is limited in the western forests by a combination of climatic (i.e. summer moisture) and edaphic factors. Third, our results complement those of previous investigations, suggesting that the impacts and threats the changing climate will pose on spruce may be different in western and eastern Estonia, with more severe effects envisaged in the western part of the region through drought‐induced physiological stress. 相似文献
18.
作物生产潜力变化具有明显的区域差异性，亟需针对不同地理单元实施有效应对措施和调控策略。选择陕西省三大地理单元（陕北高原、关中盆地和秦巴山区）为研究对象，运用全球生态区模型（GAEZ）分析了陕西省不同地理单元作物生产潜力变化趋势，探讨了不同作物生产潜力变化的区域差异，辨识出影响不同作物生产潜力变化的主要因素，结果显示：（1） 1980—2015年间，陕西省玉米生产潜力总量增加了150.55×104 t，小麦生产潜力总量则下降了402.69×104 t。（2） 关中盆地的玉米和小麦生产潜力皆最大，陕北高原次之，秦巴山区的玉米和小麦生产潜力皆最小；陕北高原和秦巴山区的玉米生产潜力皆表现出先增加后减小再增加的变化趋势，关中盆地的玉米生产潜力则先减小后增加再减小；关中盆地和秦巴山区的小麦生产潜力都呈下降趋势，陕北高原的小麦生产潜力则有所提高。（3） 土地利用变化呈现减产效应，这一效应在关中盆地尤为显著，其次为陕北高原；气候变化导致玉米生产潜力增加，使小麦生产潜力下降；气候变化对不同地理单元的影响也不相同，在陕北高原表现为增产效应，在关中盆地和秦巴山区则为减产效应。（4） 在陕北高原，气候变化的增产效应是玉米和小麦生产潜力提高的主要原因，气候变化对玉米生产潜力的影响大于对小麦的影响，耕地向草地、林地和建设用地的转化是降低作物生产潜力最主要的土地利用变化因素；在关中盆地，作物生产潜力的变化主要是受气候变化的影响，小麦受气候变化的影响较玉米为大，以建设用地占用耕地为特征的土地利用变化对玉米生产潜力的影响大于对小麦的影响；在秦巴山区，土地利用变化是玉米生产潜力变化的主要原因，而小麦生产潜力的变化主要受气候变化影响。 相似文献
19.
江苏沿海地区是中国重要的耕地后备资源基地之一,气候生产潜力能够反映该地区粮食安全保障能力大小。考虑作物不同生长期光温水协调程度,对现有气候生产潜力模型基于作物生长期进一步改进,估算江苏沿海地区14个县市三大粮食作物气候生产潜力。结果表明：基于作物生长期的气候生产潜力模型具有可行性。江苏省沿海地区水稻和小麦作物气候生产潜力受太阳有效辐射、温度和降水因素共同影响;玉米气候生产潜力主要受太阳有效辐射和温度影响,不受降水因素限制。从地域分布特征看,江苏沿海地区水稻和玉米气候生产潜力南北方向呈现梯度递增规律;小麦气候生产潜力南北方向差异不大。 相似文献
20.
The impacts of extreme weather events and climate variability on natural resource dependent farmers will further increase their vulnerability. This study describes how Adi farmers in Arunachal Pradesh (India) perceive and adapt to climate variability, and how this is influenced by gender and wealth. A total of 65 male and 71 female Adi farmers were interviewed or participated in focus group discussions. Both men and women have noticed there are fewer rainy days, longer summers, shorter winters and more erratic rainfall. However, some perceptions of change were gender and/or wealth class specific. Adi women noticed changes across areas they control including collecting forest foods, crop harvesting, and fermenting and storing of food. Men noted climate variability had made hunting wild game and marketing agricultural produce more difficult. Wealthy people were better placed to adapt to climate variability than poorer people because they could intensify their production systems. They switched to rainfed maize with improved varieties and horticultural cash crops which need more costly inputs. Wealthy people, particularly men, also received more advice and training than poorer people. Poorer farmers, particularly poor women, adapted predominantly by diversifying activities, such as using drought tolerant oil seeds and subsistence horticultural crops, accessing forest-based resources, rearing pigs and poultry, increasing fishing and the making of handicrafts. Storage, exchange and pooling of local resources were further strategies of the poor. This deeper understanding of Adi livelihood adaptation strategies will help increase their resilience by improving targeting of location specific extension services and adaptation policies. 相似文献