It is of utmost necessity to understand the dynamics of regional active accumulated temperature(AAT)to cope with the negative impacts of global warming on agroforestry development and food security and to provide a re...It is of utmost necessity to understand the dynamics of regional active accumulated temperature(AAT)to cope with the negative impacts of global warming on agroforestry development and food security and to provide a real-time and effective reference basis for regional agroforestry planning.The daily temperature data from 30 meteorological stations in Sichuan Province from 1970 to 2020,and sea surface temperature(SST)index data from the Atlantic Multiphase Oscillation(AMO)and Pacific Decadal Oscillation(PDO)were used for the study.Sichuan Province was divided into the western region(WS)and the eastern region(ES),considering 1000 m above sea level as the boundary.The spatiotemporal characteristics of≥0℃ and≥10℃ active accumulated temperature(AAT0,AAT10)in WS and ES were analyzed comprehensively using 5-day average sliding,empirical orthogonal function(EOF),ensemble empirical mode decomposition(EEMD),and multiple mutation tests.The results show that(1)AAT0 and AAT10 of WS ranged from 3034℃ to 3586℃ and 1971℃ to 2636℃,respectively,while the AAT0 and AAT10 of ES ranged from 5863℃ to 6513℃ and 4847℃ to 5875℃,respectively.The period around 1997 was a significant abrupt change,and the AAT in the province generally increased during the subsequent time period(2)AAT in the study area is mainly driven by the fluctuations of AMO,as reflected by the low-to-high variation of AAT coinciding with the jump of the cold-to-warm phase of AMO.Considering different time scale fluctuations in the past 51 years,the major cycle for both AAT0 and AAT10 in WS is 3.40 a,while the major cycles in ES are 3.64 a and 3.19 a,respectively with a sub-cycle of 7.29 a.AAT fluctuation has an insignificant periodic characteristic of 25.50 a on the interdecadal scale(3)The spatial heterogeneity of AAT in WS is prominent and is mainly reflected by the significantly warm conditions in the south of the WS region and relatively slight warm conditions in the north,as well as by the isolated cooling area in the form of"freezing point",i.e.,Xiaojin county.In contrast,the spatial variability of AAT in ES is more or less consistent,with the warming areas concentrated in the foothills of the western edge of the basin and a slight increase in AAT observed in the central part of the basin.展开更多
[Objective]The research aimed at constructing an accumulated temperature effect model for fertility alteration of two-line hybrid rice P88S.[Method]Analyze the experiment datas of fertility alteration of P88S in Haina...[Objective]The research aimed at constructing an accumulated temperature effect model for fertility alteration of two-line hybrid rice P88S.[Method]Analyze the experiment datas of fertility alteration of P88S in Hainan from 2005 to 2006.[Result]The fertilities of P88S with temperatures ranging from 26 to 28 ℃ were determined by the absolute values and the accumulation effects of the temperature.An accumulation effect model of temperatures based on the bistable state was obtained.[Conclusion]The temperature asymmetry of fertility alteration for two-line sterility line in spring and autumn can be elucidated effectively using the accumulated temperature effect model,namely,alternating from fertile to sterile requires higher temperatures,and alternating from sterile to fertile requires lower temperatures.展开更多
The objective of this study was to provide reliable basis for decision making for national food security and layout and structure adjustment of grain production in the northeastern China. The data of mean daily air te...The objective of this study was to provide reliable basis for decision making for national food security and layout and structure adjustment of grain production in the northeastern China. The data of mean daily air temperature of 1961-2009 from 106 meteorological stations in the northeastern China were chosen in this study. Using statistical methods and isoline method, the spatio-temporal changes of various decadal ≥10℃accumulated temperature and the climatic means of ≥10℃ accumulated temperature were studied in this paper. The results showed that 1) The geo- graphical distribution of ≥10℃ accumulated temperature in the northeastern China could be influenced directly by the latitude, longitude and altitude. If latitude moved one degree northward, the average decrease amplitude of the climatic means was 101.9℃ in the study area. 2) The means of decadal ≥10℃ accumulated temperature rose since the 1980s, and their increase amplitudes became larger in the 1990s and the 2010s obviously. Compared with those of the 1980s, ≥10℃ accumulated temperature increased by about 100℃ in the mountainous and plain areas in the 1990s; compared with those of the 1990s, ≥10℃ accumulated temperature increased by about 200℃ in the Hulun Buir High Plain and the Songnen Plain, and 100℃ in the Sanjiang Plain and the Liaohe Plain in the 2010s. 3) The means of the decada ≥10℃accumulated temperature for 106 meteorological stations in the northeastern China increased with the rate of 145.57℃/10yr in 1961-2009.4) The climatic means of ≥10℃ accumulated temperature increased from 1961-1990 to 1971-2000 and 1981-2009. Compared with the climatic mean of 1971-2000, that of 1981-2009 had increased by above 50℃ in most of the study area, even up to 156℃. Compared with the climatic mean of 1961-1990, that of 1981-2009 increased by above 100℃ in most parts of the study area, even up to 200℃. 5) The maximum northward shift, eastward and westward extension amplitudes of3100℃, 3300℃ and 3500℃ isolines were larger among all isolines for the climatic means of the three phases. Compared with the positions of the isolines of 1961-1990, those amplitudes of 31000C isoline of 1981-2009 were 145 km, 109 km and 64 km, respectively; those of 3300℃ isoline were 154 km, 54 km and 64 km, respectively; and the maximum northward shift of 3500℃ isoline was about 100 km.展开更多
The armyworm Mythimna roseilinea(Walker) is a major pest of grain crops in South China. So far little is known about its basic biology and ecology, making prediction of population dynamics difficult. This study exam...The armyworm Mythimna roseilinea(Walker) is a major pest of grain crops in South China. So far little is known about its basic biology and ecology, making prediction of population dynamics difficult. This study examined the relationships of individual development and population growth with temperature based on an age-stage, two-sex life table of M. roseilinea reared on maize in the laboratory at 18, 21, 24, 27 and 30℃. The highest values of net reproductive rate(R_0) and fecundity were observed at 21 and 24℃, respectively. Both the intrinsic rate of increase(r) and finite rate of increase(λ) increased significantly and mean generation time(T) decreased significantly with increasing temperature. M. roseilinea was able to develop, survive and lay eggs at all temperature regimes tested. Development rates of the egg, larval, pupal, as well as the whole pre-oviposition stages had a positive linear relationship with temperature. The calculated development threshold temperatures of egg, larval, pupal, pre-oviposition and total pre-oviposition stages were 13.29, 8.39, 14.35, 7.42, and 12.24℃, respectively, and their effective accumulated temperatures were 63.59, 445.00, 211.11, 89.02, and 698.95 degree-days, respectively. These results provide insight into temperature-based phenology and population ecology of this insect pest and will allow population prediction and management available in the field.展开更多
In order to understand the occurrence and development of Semanotus bifasciatus (Motschulsky), a borer insect of Platycladus orientalis in parts of northern and eastern China and to improve its prediction, the develo...In order to understand the occurrence and development of Semanotus bifasciatus (Motschulsky), a borer insect of Platycladus orientalis in parts of northern and eastern China and to improve its prediction, the developmental threshold temperature (C1) and effective accumulated temperature (K) of S. bifasciatus were determined under conditions of constant and variable temperatures. The results show that under constant temperatures the value of C1 has a range of 8.90±1.77℃and the value of K lies between 95.19±13.14 degree-day for eggs; the values for larvae are C1= 13.26±3.06℃ and the number of degree-day is K 2,885.07±187.87 degree-day; for pupae the ranges are C1 = 8.93±2.49℃ and K= 131.20±25.63 degree-day. Under the condition of ambient temperatures, the values for eggs are C1= 17.33±1.24℃ and K= 70.79±8.99 degree-day. It is suggested that S. bifasciatus adults over-winter in a state of dormancy, not at a diapause. Warm winter may accelerate the life cycle ofS. bifasciatus. Equations can be used to predict an early occurrence ofS. bifasciatus.展开更多
[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang...[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang, the change trends of ≥0 ℃ and ≥10 ℃ accumulated temperature in Shenyang in recent 58 years were analyzed by means of climatic statistics method, and the effects of accumulated temperature variation on agricultural production were discussed. [Result] In recent 58 years, the first day with temperature ≥0 ℃ advanced 10 d, and the last day put off slightly, while sustained days prolonged 13 d, and ≥0 ℃ accumulated temperature increased by 343 ℃·d; meanwhile, the first day with temperature ≥10 ℃ advanced 9 d, and the last day put off 8 d, while sustained days prolonged 16 d, and ≥10 ℃ accumulated temperature increased by 370 ℃·d; compared with the first 20 years, sustained days with temperature ≥0 ℃ and ≥10 ℃ prolonged 9 d in the last 20 years, and ≥0 ℃ and ≥10 ℃ accumulated temperature increased by 196 and 202 ℃·d, respectively. In addition, the increase of heat resources affected agricultural production in Shenyang. [Conclusion] The study could provide theoretical foundation for grasping heat resources variation and adjusting agriculture distribution.展开更多
Accumulated temperature,which is now widely used in agronomy,is an important ecological factor to the growth of plants,but few relative studies have been found on the vegetation area of floodplain grasslands in Poyang...Accumulated temperature,which is now widely used in agronomy,is an important ecological factor to the growth of plants,but few relative studies have been found on the vegetation area of floodplain grasslands in Poyang Lake.This research used the classification and regression tree(CART)to classify normalized vegetation area index derived from MODIS LAI(Moderate Resolution Imaging Spectroradiometer Leaf Area Index)images from 2008 to 2014,according to different climate indexes,such as mean daily air temperature(n),accumulated temperature(jw),daily maximum temperature(g),daily minimum temperature(d),accumulative precipitation(j),water level(s)and average water level for 20 days preceding(a).The results showed that:(1)The accumulated temperature and the 20-day average WL(water level)were found to have the greatest impact on variation in wetland vegetation area,and they both dominated the classification process twice;(2)Two classification thresholds of accumulated temperature were 790°C and 1784°C,approximately corresponding to the beginning of April and midMay;(3)790°C could also be used as a threshold to select remote sensing images to analysis the annual variability of vegetation,i.e.while accumulated temperature is lower than 790°C,remote sensing images of similar accumulated temperature rather than similar date should be selected from different years for comparison.We also found that,effects of different hydrological factors on area of floodplain grasslands showed stage characteristics:(1)From January to March,water level changes slowly with less rainfall,as a result,the 20-day average WL which can interpret the hydrologic characteristics smoothly showed significant importance in this stage;(2)While entering April,intense rainfall make accumulative precipitation to be the dominating factor of classification;(3)From late April to mid-May,in condition of accumulative precipitation higher than 405 mm,daily water level is of most importance,because to the flood recession process as well as rapid water level fluctuations.展开更多
Five rice varieties were planted to determine the variation of the yield and quality traits in five different regions in a cold area of China. The results showed that the number of the panicles, the number of grains p...Five rice varieties were planted to determine the variation of the yield and quality traits in five different regions in a cold area of China. The results showed that the number of the panicles, the number of grains per panicle and percentage of head-milled rice displayed quadratic curves against the accumulated temperature, and the sterile rate decreased with greater accumulated temperature. However, 1 000-grain weight had no correlation with the accumulated temperature and protein content, amylose content and taste also had no obvious relation with the accumulated temperature. The results from the accumulated temperature differed with rice variety, so the temperature insensitive type variety should be proposed for production.展开更多
[ Objective] The paper was to study the relationship between temperature and development of Potosia brevitarsis Lewis. [ Methods] Six constant tem- peratures (21, 24, 27, 30, 33 and 36 ℃ ) were set in the laborator...[ Objective] The paper was to study the relationship between temperature and development of Potosia brevitarsis Lewis. [ Methods] Six constant tem- peratures (21, 24, 27, 30, 33 and 36 ℃ ) were set in the laboratory to study developmental threshold temperature and effective accumulated temperature of P. brevitarsis. [ Result] The developmental durations of various states of P. brevitarsis were shortened with the increasing temperature ranged from 21 ℃ to 36 ℃ ; the developmental rates were accelerated with the increasing temperature. The developmental threshold temperatures of egg, larva, pupa and pre-ovipesition of adult were estimated to be 12.79, 9.15, 14.86 and 13.80 ℃, respectively; the effective accumulated temperature were 136.25, 3 031.31,308.92 and 98.35 d · ℃, respectively. The developmental threshold temperature and effective amcumulated temperature for one complete generation were 9.96 ℃ and 3 628.73 d · ℃, re- spectively. Combined with meteorological data, the theoretical generation number of P. brevitarsis occurred in Shihezi was presumed to be one per year, which was basically coincided with actual occurrence generations in fields. [ Conclusion] The paper provided theoretical basis for effective control against P. brevitarsis.展开更多
[Objective] The aim of the study was to find out the cold/warm change characteristics in crop growing season and their relationship with food production in Heilongjiang Province.[Method] The temporal and spatial varia...[Objective] The aim of the study was to find out the cold/warm change characteristics in crop growing season and their relationship with food production in Heilongjiang Province.[Method] The temporal and spatial variation on the accumulated temperature steadily above 10 ℃ and its lasting days,the beginning date,the ending dates were investigated,and the relationship between food production and cold/warm climate in Heilongjiang Province during 1961-2009 was further analyzed.[Result] The results showed that the provincial average accumulated temperature steadily above 10 ℃ has increased by 355.4 ℃,the lasting days of accumulated temperature steadily above 10 ℃ has extended by 13d,and the beginning date has advanced by 8 d,while the ending date has delayed by 5 d in Heilongjiang Province during 49 years.Climate warming began from the 1980s,and the most significant period of climate warming was after the 1990s.The food production is closely related to cold/warm climate in Heilongjiang Province.[Conclusion] The climate warming was significant in crop growing season of Heilongjiang Province in the past 49 years,providing more favorable climatic conditions for the agricultural production.展开更多
[Objective] This study aimed to observe the embryonic development process of Leiocassis crassilabris. [Method] Wild L. crassilabris collected from the Nanjing section of the Yangtze River was used as parent fish for i...[Objective] This study aimed to observe the embryonic development process of Leiocassis crassilabris. [Method] Wild L. crassilabris collected from the Nanjing section of the Yangtze River was used as parent fish for intensive breeding and propagation by artificial insemination. The entire embryonic development process of L. crassilabris from insemination to hatching out of larvae fish was observed consecutively. [Result] Fertilized eggs of L. crassilabris are spherical, and the egg diameter is about 2.2-2.4 mm after water absorption; under conditions of water temperature ranging from 27 to 28 ℃, the embryonic development of L. crassilabris from insemination to hatching out of larvae fish lasted 2 496 min, with a total accumulated temperature of 1 123-1 165 h·℃. [Conclusion] This study is advantageous to better understand the characteristics of embryonic development of L. crassilabris and provides basic biological data for protection and utilization of fish resources and other related work.展开更多
The fall armyworm(FAW),Spodoptera frugiperda is one of the most damaging crop pests,and it has become major threat to the food security of many countries.In order to monitor possible invasion of this pest into China,a...The fall armyworm(FAW),Spodoptera frugiperda is one of the most damaging crop pests,and it has become major threat to the food security of many countries.In order to monitor possible invasion of this pest into China,a searchlight trap was established in March 2018 in western Yunnan Province,China,where it has served as the"first station"for many pests that have migrated from Myanmar to China.A number of suspected FAW moths were captured and identified by DNA sequencing.The results showed that the FAW moth was first captured on December 11 and formed its first immigration peak in mid-December 2018.DNA detection revealed that the early invading FAW population was the"corn-strain".The field survey indicated that the pest mainly colonized corn in Pu’er,Dehong and Baoshan areas.Migration trajectory simulation implied that the moths might have mainly come from the eastern area in the mid-latitude region of Myanmar(20-25°N,94-100°E).This case study confirmed the first immigration of FAW into China,and will be helpful for guiding monitoring and management work to control this pest.展开更多
Daily temperature data from 599 stations across China for the years 1961 to 2007 were used to analyze the changes in the natural regional boundaries. The results show that the accumulated temperature ≥10℃ and its du...Daily temperature data from 599 stations across China for the years 1961 to 2007 were used to analyze the changes in the natural regional boundaries. The results show that the accumulated temperature ≥10℃ and its duration changed dramatically from the end of 1990s to the early 21 st century. The amplitude of natural regional boundaries was greater in the 21st century than it was in the 20th century. In the eastern region of China, the climatic zones were migrating generally northward, with the northern edge of the subtropical zone and the eastern section of the warm temperate zone showing an obvious northward shift of up to 1-3° of latitude. The climatic zones moved south in the Qinghal-Tibet Plateau, western Inner Mongolia, and some areas of western Xinjiang, and slightly to the north in other parts of the western region.展开更多
[ Objective ] The paper was to study the occurrence regularity of Lysiphlebus testaceipes Cresson. [ Method ] With Aphis craccivora Koch as the breeding host, developmental duration, development threshold temperature ...[ Objective ] The paper was to study the occurrence regularity of Lysiphlebus testaceipes Cresson. [ Method ] With Aphis craccivora Koch as the breeding host, developmental duration, development threshold temperature and effective accumulative temperatme of L. testaceipes Cresson were studied at six constant tem- peratures of 12, 16, 20, 24, 28 and 32℃ in the laboratory, respectively. [ Result] The developmental durations of each growth stage of L. testaceipes Cresson were shortened with the increasing temperature ranged from 12 to 32℃, and the growth rate was significantly accelerated with the increasing temperature. However, when the temperature was up to 32℃, the growth and development from mummy to adult was suppressed, and the developmental duration was extended for 0.45 d than that at 28℃. The developmental durations from egg to adult at 12, 16, 20, 24, 28 and 32℃ were 38.50, 21.25, 14.11, 12.17, 10.28 and 9.01 d, respectively. The developmental threshold temperatures of egg-mummy, mummy-adult and egg-adult were estimated to be 6.5, 6.25 and 5.36℃, respectively; and the effective accumulated temperatures were 136.28, 75.74 and 227.23 d·℃, respectively. [ Conclusion] Forecast formula of developmental duration and Logistic models were established according to effective accumulated temperature and developmental threshold temperature.展开更多
[Objective] The aim was to study variation characteristics of thermal resources in east Hexi Corridor in recent 50 years. [Method] Using the daily average air temperature data from 5 meteorological stations in east He...[Objective] The aim was to study variation characteristics of thermal resources in east Hexi Corridor in recent 50 years. [Method] Using the daily average air temperature data from 5 meteorological stations in east Hexi Corridor from 1959 to 2010, the variation of accumulated temperature steadily above 10 and 0 ℃, lasting days, the beginning and ending day were summarized, and then the variation characteristics of thermal resources under the background of climate warming were analyzed. [Result] The air temperature increased continuously in east Hexi Corridor, and the climatic trend rate of the annual average air temperature was 0.34 ℃/10 a, more significant than any other region in China. And it was well correlated with the thermal resource indexes such as the accumulated temperature steadily above 10 and 0 ℃, and their lasting days, and the beginning and ending day. Climate warming had made the accumulated temperature steadily above 10 and 0 ℃ increased significantly in east Hexi Corridor widespread. The accumulated temperature steadily above 10 and 0 ℃ had increased significantly. The lasting days of accumulated temperature steadily above 10 and 0 ℃ increased significantly too. The delay of ending days was more significant than the advancing of beginning days. [Conclusion] These changes in thermal resources were conductive to increase food production and maintain the stability of food production in east Hexi Corridor.展开更多
[Objective] The aim was to analyze and explore division of agro-climatic zones of Beibei District in Chongqing municipality. [Method] According to major triple-cropping crops in Beibei District, such as wheat (spring...[Objective] The aim was to analyze and explore division of agro-climatic zones of Beibei District in Chongqing municipality. [Method] According to major triple-cropping crops in Beibei District, such as wheat (spring and winter), rice (midmaturation early season rice, later-maturation early rice, later-maturation late rice and middle-season rice), heat demanded by rapeseed, different cultivation methods and cultivation regions with different crop varieties, the accumulated temperatures in four cultivation regions featured by special cultivation methods and variety-matching are concluded. Based on average and accumulated temperatures in different locations in 30 y and other factors, such as terrain, elevation, rainfall and soil property, Beibei District can be classified into four agro-climatic zones. [Result] Four cultivation regions are as follows: the 1st cultivation region where accumulated temperature in T y is ≥6 530 ℃, the 2nd cultivation region where 6 530 ℃ accumulated temperature in T y≥6 350 ℃, the 3rd cultivation region where 6 530 ℃ accumulated temperature in T y≥5 990 ℃, and the 4th cultivation region where accumulated temperature in T y is ≤5 990 ℃. Beibei District can be classified into four agro-climatic zones, involving lower hill temperate zone, higher hill temperate zone, single-slope lower hills and karst temperate zone, and lower ridge cool zone. [Conclusion] Based on characters of four agro-climatic zones and accumulated temperatures required in four cultivation regions, agro-climatic zones can be classified in Beibei District, providing references for rational arrangement of crops and is of significance for stabilization of agricultural production, improvement of crops and increase of farmers’ income.展开更多
In the study, Southwest peony varieties group of Paeonia suffruticosa "Hongdan Lan" were analyzed, test was mainly divided into two parts, one is the nature of the low temperature, through the external environment i...In the study, Southwest peony varieties group of Paeonia suffruticosa "Hongdan Lan" were analyzed, test was mainly divided into two parts, one is the nature of the low temperature, through the external environment is mainly (temperature, light) gibberellin and nutrition solution regulation, on the Tianpeng peony florescence control technological research. The second is to explore the flower forcing peony after anthesis regeneration technique. The main research results: comprehensive gibberellin peony flower induction of morphological and physiological indexes, such as gibberellin concentration of 150 mgFL and 200 mg/L the effect of flower induction was better than the other treatments; gibberelin (GA3) breaking the dormancy of the peony to blossom ahead of time has the promoter action, also has certain effect on nutritional growth; to premature flowering the abscisic acid (ABA) has opposite effect; whereas auxin (IAA) and corn (ZT) effect was not obvious; rejuvenation results showed that after a year of conservation and managemental measures, flower induction after the flower of peony played a very important role in the restoration. After the winter flower induction, peony flowerpot of soil hardening, through the soil replacement, repair of roots, flower peony recovery showed a very significant effect.展开更多
To study the temporal and spatial changes of heat resources to serve agricultural production and economic development. The climate data from 1958 to 2017 were selected, and the temporal and spatial changes of heat res...To study the temporal and spatial changes of heat resources to serve agricultural production and economic development. The climate data from 1958 to 2017 were selected, and the temporal and spatial changes of heat resources in Liaoning, China were analyzed by using the method of climate diagnosis and analysis. The results show that: the southern coastal area of Liaoning has the most heat resources, the northwestern hilly area and the eastern mountainous area the least, and the central plain area in the middle distribution pattern;compared with 1958-1980, 1981-2017 ≥0°C, ≥10°C accumulated temperature, etc. The value line is advanced 100-160km northward. The accumulated temperature of ≥0°C and ≥10°C in Liaoning experienced abrupt changes in climate in 1993 and 1994, and the climate abrupt change in the southern coastal area was earlier than that in the inland. , the increase in the northwestern hilly area and the eastern mountainous area is less than that in the central plain area and the southern coastal area. The study on the impact on meteorological services found that the increase or decrease of heat resources has a significant impact on agro-meteorological services, which can prolong the growing season of crops, relatively reduce the damage of frost, improve comprehensive utilization of land, and increase crop yields;at the same time, with the increase of heat resources and the northward expansion of the isoline of accumulated temperature, the area affected by pests and diseases has expanded, which has aggravated the harm to agriculture economic burden.展开更多
The spatial and temporal variations of ≥10℃ annual accumulated temperature (AAT10) were analyzed by using the linear trend line method, cumulative anomaly method and the multiple linear regression model (MLRM) i...The spatial and temporal variations of ≥10℃ annual accumulated temperature (AAT10) were analyzed by using the linear trend line method, cumulative anomaly method and the multiple linear regression model (MLRM) interpolation method based on the daily meteorological observation data from 104 meteorological stations in Southern China and surrounding 39 meteorological stations from 1960 to 2011. The results show that: (1) From time scale point of view, the climatic trend of the AAT10 increased with an average of 7.54℃/decade in Southern China since 1960. The area of AAT10〈6000℃ decreased from 1960 to 2011, and the area of 6000℃〈AAT10〈8000℃ decreased from 1960 to 1979 and increased from 1980 to 2011, and the area of AAT10〉8000℃ increased from 1960 to 2011. (2) From spatial scale point of view, the AAT10 in Southern China reduced with increasing latitude and reduced with increasing altitude. The proportion of the area with 5000℃〈 AAT10〈8000℃ accounted for 70% of the study area, followed by the area of 4000℃〈AAT10 〈5000℃; and the area of AAT10〈4000℃ and AAT10〉8000℃ was the least. Climate trend rate of the AAT10 at 99% of the meteorological stations was greater than zero, which indicated that the AAT10 increased significantly in the central Yunnan province, southern Guangdong province as well as Hainan Island. (3) Comparison of period A (1960-1989) and period B (1980-2011) with the change of temperature zones shows that the boundaries of cool temperate zone, mid-temperate zone and warm temperate zone shifted northward and shrank westward. The northern boundary of north subtropical zone and mid-subtropical zone shifted northward gradually by over 0.5° and 0.5° latitude, respectively. The western part of northern boundary of south subtropical zone and marginal tropical zone shifted northward by 0.2° and 0.4° latitude, respectively. The change of temperature zones was expanded to high altitude and latitude. (4) The increase of the AAT10 is conducive to the production of tropical crops planted, which will increase the planting area that was suitable for tropical crops, and expand the planting boundaries to high latitude and high altitude.展开更多
Temperature is an important physical factor, which strongly influences biomass and metabolic activity. In this study, the effects of temperature on the anoxic metabolism of nitrite (NO2) to nitrous oxide (N2O) by ...Temperature is an important physical factor, which strongly influences biomass and metabolic activity. In this study, the effects of temperature on the anoxic metabolism of nitrite (NO2) to nitrous oxide (N2O) by polyphosphate accumulating organisms, and the process of the accumulation of N2O (during nitrite reduction), which acts as an electron acceptor, were investigated using 91% :e 4% Candidatus Accumulibacterphosphatis sludge. The results showed that N2O is accumulated when Accumulibacter first utilize nitrite instead of oxygen as the sole electron acceptor during the denitrifying phosphorus removal process. Properties such as nitrite reduction rate, phosphorus uptake rate, N2O reduction rate, and polyhydroxyalkanoate degradation rate were all influenced by temperature variation (over the range from 10 to 30℃ reaching maximum values at 25℃). The reduction rate of N2O by N2O reductase was more sensitive to temperature when N2O was utilized as the sole electron acceptor instead of NO2, and the N2O reduction rates, ranging from 0.48 to 3.53 N2O-N/(hr.g VSS), increased to 1.45 to 8.60 mg N2O-N/(hr·g VSS). The kinetics processes for temperature variation of 10 to 30℃ were (01 = 1.140-1.216 and θ2 = 1.139-1.167). In the range of 10℃ to 30℃, almost all of the anoxic stoichiometry was sensitive to temperature changes. In addition, a rise in N2O reduction activity leading to a decrease in N2O accumulation in long term operations at the optimal temperature (27℃ calculated by the Arrhenius model).展开更多
基金the National Natural Science Foundation of China(Grant No.51779114)。
文摘It is of utmost necessity to understand the dynamics of regional active accumulated temperature(AAT)to cope with the negative impacts of global warming on agroforestry development and food security and to provide a real-time and effective reference basis for regional agroforestry planning.The daily temperature data from 30 meteorological stations in Sichuan Province from 1970 to 2020,and sea surface temperature(SST)index data from the Atlantic Multiphase Oscillation(AMO)and Pacific Decadal Oscillation(PDO)were used for the study.Sichuan Province was divided into the western region(WS)and the eastern region(ES),considering 1000 m above sea level as the boundary.The spatiotemporal characteristics of≥0℃ and≥10℃ active accumulated temperature(AAT0,AAT10)in WS and ES were analyzed comprehensively using 5-day average sliding,empirical orthogonal function(EOF),ensemble empirical mode decomposition(EEMD),and multiple mutation tests.The results show that(1)AAT0 and AAT10 of WS ranged from 3034℃ to 3586℃ and 1971℃ to 2636℃,respectively,while the AAT0 and AAT10 of ES ranged from 5863℃ to 6513℃ and 4847℃ to 5875℃,respectively.The period around 1997 was a significant abrupt change,and the AAT in the province generally increased during the subsequent time period(2)AAT in the study area is mainly driven by the fluctuations of AMO,as reflected by the low-to-high variation of AAT coinciding with the jump of the cold-to-warm phase of AMO.Considering different time scale fluctuations in the past 51 years,the major cycle for both AAT0 and AAT10 in WS is 3.40 a,while the major cycles in ES are 3.64 a and 3.19 a,respectively with a sub-cycle of 7.29 a.AAT fluctuation has an insignificant periodic characteristic of 25.50 a on the interdecadal scale(3)The spatial heterogeneity of AAT in WS is prominent and is mainly reflected by the significantly warm conditions in the south of the WS region and relatively slight warm conditions in the north,as well as by the isolated cooling area in the form of"freezing point",i.e.,Xiaojin county.In contrast,the spatial variability of AAT in ES is more or less consistent,with the warming areas concentrated in the foothills of the western edge of the basin and a slight increase in AAT observed in the central part of the basin.
基金Supported by Tianjin University of Science & Technology LaboratoryOpen Fund(1014A109)National 863 Science Plan(2010AA101301)National Natural Science Foundation(20903071)~~
文摘[Objective]The research aimed at constructing an accumulated temperature effect model for fertility alteration of two-line hybrid rice P88S.[Method]Analyze the experiment datas of fertility alteration of P88S in Hainan from 2005 to 2006.[Result]The fertilities of P88S with temperatures ranging from 26 to 28 ℃ were determined by the absolute values and the accumulation effects of the temperature.An accumulation effect model of temperatures based on the bistable state was obtained.[Conclusion]The temperature asymmetry of fertility alteration for two-line sterility line in spring and autumn can be elucidated effectively using the accumulated temperature effect model,namely,alternating from fertile to sterile requires higher temperatures,and alternating from sterile to fertile requires lower temperatures.
基金Under the auspices of National Natural Science Foundation of China (No. 40771190)Special Fund for Meteorological Scientific Research in the Public Interest (No. GYHY200706030)
文摘The objective of this study was to provide reliable basis for decision making for national food security and layout and structure adjustment of grain production in the northeastern China. The data of mean daily air temperature of 1961-2009 from 106 meteorological stations in the northeastern China were chosen in this study. Using statistical methods and isoline method, the spatio-temporal changes of various decadal ≥10℃accumulated temperature and the climatic means of ≥10℃ accumulated temperature were studied in this paper. The results showed that 1) The geo- graphical distribution of ≥10℃ accumulated temperature in the northeastern China could be influenced directly by the latitude, longitude and altitude. If latitude moved one degree northward, the average decrease amplitude of the climatic means was 101.9℃ in the study area. 2) The means of decadal ≥10℃ accumulated temperature rose since the 1980s, and their increase amplitudes became larger in the 1990s and the 2010s obviously. Compared with those of the 1980s, ≥10℃ accumulated temperature increased by about 100℃ in the mountainous and plain areas in the 1990s; compared with those of the 1990s, ≥10℃ accumulated temperature increased by about 200℃ in the Hulun Buir High Plain and the Songnen Plain, and 100℃ in the Sanjiang Plain and the Liaohe Plain in the 2010s. 3) The means of the decada ≥10℃accumulated temperature for 106 meteorological stations in the northeastern China increased with the rate of 145.57℃/10yr in 1961-2009.4) The climatic means of ≥10℃ accumulated temperature increased from 1961-1990 to 1971-2000 and 1981-2009. Compared with the climatic mean of 1971-2000, that of 1981-2009 had increased by above 50℃ in most of the study area, even up to 156℃. Compared with the climatic mean of 1961-1990, that of 1981-2009 increased by above 100℃ in most parts of the study area, even up to 200℃. 5) The maximum northward shift, eastward and westward extension amplitudes of3100℃, 3300℃ and 3500℃ isolines were larger among all isolines for the climatic means of the three phases. Compared with the positions of the isolines of 1961-1990, those amplitudes of 31000C isoline of 1981-2009 were 145 km, 109 km and 64 km, respectively; those of 3300℃ isoline were 154 km, 54 km and 64 km, respectively; and the maximum northward shift of 3500℃ isoline was about 100 km.
基金funded by the Special Fund for Agro-scientific Research in the Public Interest of China (201403031)the China Agriculture Research System (CARS-22)+2 种基金the National Key Research and Development Program of China (2017YFD0201802, 2017YFD0201701)he National Natural Science Foundation of China (31672019, 31371947)the Beijing Natural Science Foundation, China (6172030)
文摘The armyworm Mythimna roseilinea(Walker) is a major pest of grain crops in South China. So far little is known about its basic biology and ecology, making prediction of population dynamics difficult. This study examined the relationships of individual development and population growth with temperature based on an age-stage, two-sex life table of M. roseilinea reared on maize in the laboratory at 18, 21, 24, 27 and 30℃. The highest values of net reproductive rate(R_0) and fecundity were observed at 21 and 24℃, respectively. Both the intrinsic rate of increase(r) and finite rate of increase(λ) increased significantly and mean generation time(T) decreased significantly with increasing temperature. M. roseilinea was able to develop, survive and lay eggs at all temperature regimes tested. Development rates of the egg, larval, pupal, as well as the whole pre-oviposition stages had a positive linear relationship with temperature. The calculated development threshold temperatures of egg, larval, pupal, pre-oviposition and total pre-oviposition stages were 13.29, 8.39, 14.35, 7.42, and 12.24℃, respectively, and their effective accumulated temperatures were 63.59, 445.00, 211.11, 89.02, and 698.95 degree-days, respectively. These results provide insight into temperature-based phenology and population ecology of this insect pest and will allow population prediction and management available in the field.
文摘In order to understand the occurrence and development of Semanotus bifasciatus (Motschulsky), a borer insect of Platycladus orientalis in parts of northern and eastern China and to improve its prediction, the developmental threshold temperature (C1) and effective accumulated temperature (K) of S. bifasciatus were determined under conditions of constant and variable temperatures. The results show that under constant temperatures the value of C1 has a range of 8.90±1.77℃and the value of K lies between 95.19±13.14 degree-day for eggs; the values for larvae are C1= 13.26±3.06℃ and the number of degree-day is K 2,885.07±187.87 degree-day; for pupae the ranges are C1 = 8.93±2.49℃ and K= 131.20±25.63 degree-day. Under the condition of ambient temperatures, the values for eggs are C1= 17.33±1.24℃ and K= 70.79±8.99 degree-day. It is suggested that S. bifasciatus adults over-winter in a state of dormancy, not at a diapause. Warm winter may accelerate the life cycle ofS. bifasciatus. Equations can be used to predict an early occurrence ofS. bifasciatus.
基金Supported by Scientific Research Project of Shenyang Science and Technology Bureau([2010]Number 15)
文摘[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang, the change trends of ≥0 ℃ and ≥10 ℃ accumulated temperature in Shenyang in recent 58 years were analyzed by means of climatic statistics method, and the effects of accumulated temperature variation on agricultural production were discussed. [Result] In recent 58 years, the first day with temperature ≥0 ℃ advanced 10 d, and the last day put off slightly, while sustained days prolonged 13 d, and ≥0 ℃ accumulated temperature increased by 343 ℃·d; meanwhile, the first day with temperature ≥10 ℃ advanced 9 d, and the last day put off 8 d, while sustained days prolonged 16 d, and ≥10 ℃ accumulated temperature increased by 370 ℃·d; compared with the first 20 years, sustained days with temperature ≥0 ℃ and ≥10 ℃ prolonged 9 d in the last 20 years, and ≥0 ℃ and ≥10 ℃ accumulated temperature increased by 196 and 202 ℃·d, respectively. In addition, the increase of heat resources affected agricultural production in Shenyang. [Conclusion] The study could provide theoretical foundation for grasping heat resources variation and adjusting agriculture distribution.
基金This work was supported by the National Natural Science Foundation of China“Study on the dynamic mechanism of grassland ecosystem response to climate change in Qinghai Plateau”under grant number U20A2098the Second Tibet Plateau Scientific Expedition and Research Program(STEP)under grant number 2019QZKK0804.
文摘Accumulated temperature,which is now widely used in agronomy,is an important ecological factor to the growth of plants,but few relative studies have been found on the vegetation area of floodplain grasslands in Poyang Lake.This research used the classification and regression tree(CART)to classify normalized vegetation area index derived from MODIS LAI(Moderate Resolution Imaging Spectroradiometer Leaf Area Index)images from 2008 to 2014,according to different climate indexes,such as mean daily air temperature(n),accumulated temperature(jw),daily maximum temperature(g),daily minimum temperature(d),accumulative precipitation(j),water level(s)and average water level for 20 days preceding(a).The results showed that:(1)The accumulated temperature and the 20-day average WL(water level)were found to have the greatest impact on variation in wetland vegetation area,and they both dominated the classification process twice;(2)Two classification thresholds of accumulated temperature were 790°C and 1784°C,approximately corresponding to the beginning of April and midMay;(3)790°C could also be used as a threshold to select remote sensing images to analysis the annual variability of vegetation,i.e.while accumulated temperature is lower than 790°C,remote sensing images of similar accumulated temperature rather than similar date should be selected from different years for comparison.We also found that,effects of different hydrological factors on area of floodplain grasslands showed stage characteristics:(1)From January to March,water level changes slowly with less rainfall,as a result,the 20-day average WL which can interpret the hydrologic characteristics smoothly showed significant importance in this stage;(2)While entering April,intense rainfall make accumulative precipitation to be the dominating factor of classification;(3)From late April to mid-May,in condition of accumulative precipitation higher than 405 mm,daily water level is of most importance,because to the flood recession process as well as rapid water level fluctuations.
基金Supported by the Public Industry Project of Ministry of Agriculture(201303126)Postdoctoral Fund of Heilongjiang Province(LBH-Z13189)Innovation Project of Institute(2012ZD013)
文摘Five rice varieties were planted to determine the variation of the yield and quality traits in five different regions in a cold area of China. The results showed that the number of the panicles, the number of grains per panicle and percentage of head-milled rice displayed quadratic curves against the accumulated temperature, and the sterile rate decreased with greater accumulated temperature. However, 1 000-grain weight had no correlation with the accumulated temperature and protein content, amylose content and taste also had no obvious relation with the accumulated temperature. The results from the accumulated temperature differed with rice variety, so the temperature insensitive type variety should be proposed for production.
基金Supported by National Natural Science Foundation of China(31360452)&National Natural Science Foundation of China(41161068)Guide Project of Xinjiang Academy of Agricultural and Reclamation Science(YYD2009-3)
文摘[ Objective] The paper was to study the relationship between temperature and development of Potosia brevitarsis Lewis. [ Methods] Six constant tem- peratures (21, 24, 27, 30, 33 and 36 ℃ ) were set in the laboratory to study developmental threshold temperature and effective accumulated temperature of P. brevitarsis. [ Result] The developmental durations of various states of P. brevitarsis were shortened with the increasing temperature ranged from 21 ℃ to 36 ℃ ; the developmental rates were accelerated with the increasing temperature. The developmental threshold temperatures of egg, larva, pupa and pre-ovipesition of adult were estimated to be 12.79, 9.15, 14.86 and 13.80 ℃, respectively; the effective accumulated temperature were 136.25, 3 031.31,308.92 and 98.35 d · ℃, respectively. The developmental threshold temperature and effective amcumulated temperature for one complete generation were 9.96 ℃ and 3 628.73 d · ℃, re- spectively. Combined with meteorological data, the theoretical generation number of P. brevitarsis occurred in Shihezi was presumed to be one per year, which was basically coincided with actual occurrence generations in fields. [ Conclusion] The paper provided theoretical basis for effective control against P. brevitarsis.
基金Supported by Program for Science and Technology Development in Heilongjiang Province(GC06C103-05)~~
文摘[Objective] The aim of the study was to find out the cold/warm change characteristics in crop growing season and their relationship with food production in Heilongjiang Province.[Method] The temporal and spatial variation on the accumulated temperature steadily above 10 ℃ and its lasting days,the beginning date,the ending dates were investigated,and the relationship between food production and cold/warm climate in Heilongjiang Province during 1961-2009 was further analyzed.[Result] The results showed that the provincial average accumulated temperature steadily above 10 ℃ has increased by 355.4 ℃,the lasting days of accumulated temperature steadily above 10 ℃ has extended by 13d,and the beginning date has advanced by 8 d,while the ending date has delayed by 5 d in Heilongjiang Province during 49 years.Climate warming began from the 1980s,and the most significant period of climate warming was after the 1990s.The food production is closely related to cold/warm climate in Heilongjiang Province.[Conclusion] The climate warming was significant in crop growing season of Heilongjiang Province in the past 49 years,providing more favorable climatic conditions for the agricultural production.
基金Supported by Science and Technology Support Program of Science and Technology Department of Jiangsu Province(BE2009335)~~
文摘[Objective] This study aimed to observe the embryonic development process of Leiocassis crassilabris. [Method] Wild L. crassilabris collected from the Nanjing section of the Yangtze River was used as parent fish for intensive breeding and propagation by artificial insemination. The entire embryonic development process of L. crassilabris from insemination to hatching out of larvae fish was observed consecutively. [Result] Fertilized eggs of L. crassilabris are spherical, and the egg diameter is about 2.2-2.4 mm after water absorption; under conditions of water temperature ranging from 27 to 28 ℃, the embryonic development of L. crassilabris from insemination to hatching out of larvae fish lasted 2 496 min, with a total accumulated temperature of 1 123-1 165 h·℃. [Conclusion] This study is advantageous to better understand the characteristics of embryonic development of L. crassilabris and provides basic biological data for protection and utilization of fish resources and other related work.
基金supported by the National Natural Science Foundation of China(31727901)。
文摘The fall armyworm(FAW),Spodoptera frugiperda is one of the most damaging crop pests,and it has become major threat to the food security of many countries.In order to monitor possible invasion of this pest into China,a searchlight trap was established in March 2018 in western Yunnan Province,China,where it has served as the"first station"for many pests that have migrated from Myanmar to China.A number of suspected FAW moths were captured and identified by DNA sequencing.The results showed that the FAW moth was first captured on December 11 and formed its first immigration peak in mid-December 2018.DNA detection revealed that the early invading FAW population was the"corn-strain".The field survey indicated that the pest mainly colonized corn in Pu’er,Dehong and Baoshan areas.Migration trajectory simulation implied that the moths might have mainly come from the eastern area in the mid-latitude region of Myanmar(20-25°N,94-100°E).This case study confirmed the first immigration of FAW into China,and will be helpful for guiding monitoring and management work to control this pest.
基金supported by the National Natural Science Foundation of China (Grant No.40875053)
文摘Daily temperature data from 599 stations across China for the years 1961 to 2007 were used to analyze the changes in the natural regional boundaries. The results show that the accumulated temperature ≥10℃ and its duration changed dramatically from the end of 1990s to the early 21 st century. The amplitude of natural regional boundaries was greater in the 21st century than it was in the 20th century. In the eastern region of China, the climatic zones were migrating generally northward, with the northern edge of the subtropical zone and the eastern section of the warm temperate zone showing an obvious northward shift of up to 1-3° of latitude. The climatic zones moved south in the Qinghal-Tibet Plateau, western Inner Mongolia, and some areas of western Xinjiang, and slightly to the north in other parts of the western region.
基金National Key R&D Project"Prevention and Control Techniques and Product Development of Natural Enemies"(SQ2017ZY060059)
文摘[ Objective ] The paper was to study the occurrence regularity of Lysiphlebus testaceipes Cresson. [ Method ] With Aphis craccivora Koch as the breeding host, developmental duration, development threshold temperature and effective accumulative temperatme of L. testaceipes Cresson were studied at six constant tem- peratures of 12, 16, 20, 24, 28 and 32℃ in the laboratory, respectively. [ Result] The developmental durations of each growth stage of L. testaceipes Cresson were shortened with the increasing temperature ranged from 12 to 32℃, and the growth rate was significantly accelerated with the increasing temperature. However, when the temperature was up to 32℃, the growth and development from mummy to adult was suppressed, and the developmental duration was extended for 0.45 d than that at 28℃. The developmental durations from egg to adult at 12, 16, 20, 24, 28 and 32℃ were 38.50, 21.25, 14.11, 12.17, 10.28 and 9.01 d, respectively. The developmental threshold temperatures of egg-mummy, mummy-adult and egg-adult were estimated to be 6.5, 6.25 and 5.36℃, respectively; and the effective accumulated temperatures were 136.28, 75.74 and 227.23 d·℃, respectively. [ Conclusion] Forecast formula of developmental duration and Logistic models were established according to effective accumulated temperature and developmental threshold temperature.
基金Supported by China Meteorological Bureau Program "Study on Drought Disaster in Gansu Province in Future 40 Years under the Background of Climate Changes"
文摘[Objective] The aim was to study variation characteristics of thermal resources in east Hexi Corridor in recent 50 years. [Method] Using the daily average air temperature data from 5 meteorological stations in east Hexi Corridor from 1959 to 2010, the variation of accumulated temperature steadily above 10 and 0 ℃, lasting days, the beginning and ending day were summarized, and then the variation characteristics of thermal resources under the background of climate warming were analyzed. [Result] The air temperature increased continuously in east Hexi Corridor, and the climatic trend rate of the annual average air temperature was 0.34 ℃/10 a, more significant than any other region in China. And it was well correlated with the thermal resource indexes such as the accumulated temperature steadily above 10 and 0 ℃, and their lasting days, and the beginning and ending day. Climate warming had made the accumulated temperature steadily above 10 and 0 ℃ increased significantly in east Hexi Corridor widespread. The accumulated temperature steadily above 10 and 0 ℃ had increased significantly. The lasting days of accumulated temperature steadily above 10 and 0 ℃ increased significantly too. The delay of ending days was more significant than the advancing of beginning days. [Conclusion] These changes in thermal resources were conductive to increase food production and maintain the stability of food production in east Hexi Corridor.
基金Supported by Key Technology Research and Development Program of Beibei District in Chongqing municipality (2012-11)~~
文摘[Objective] The aim was to analyze and explore division of agro-climatic zones of Beibei District in Chongqing municipality. [Method] According to major triple-cropping crops in Beibei District, such as wheat (spring and winter), rice (midmaturation early season rice, later-maturation early rice, later-maturation late rice and middle-season rice), heat demanded by rapeseed, different cultivation methods and cultivation regions with different crop varieties, the accumulated temperatures in four cultivation regions featured by special cultivation methods and variety-matching are concluded. Based on average and accumulated temperatures in different locations in 30 y and other factors, such as terrain, elevation, rainfall and soil property, Beibei District can be classified into four agro-climatic zones. [Result] Four cultivation regions are as follows: the 1st cultivation region where accumulated temperature in T y is ≥6 530 ℃, the 2nd cultivation region where 6 530 ℃ accumulated temperature in T y≥6 350 ℃, the 3rd cultivation region where 6 530 ℃ accumulated temperature in T y≥5 990 ℃, and the 4th cultivation region where accumulated temperature in T y is ≤5 990 ℃. Beibei District can be classified into four agro-climatic zones, involving lower hill temperate zone, higher hill temperate zone, single-slope lower hills and karst temperate zone, and lower ridge cool zone. [Conclusion] Based on characters of four agro-climatic zones and accumulated temperatures required in four cultivation regions, agro-climatic zones can be classified in Beibei District, providing references for rational arrangement of crops and is of significance for stabilization of agricultural production, improvement of crops and increase of farmers’ income.
文摘In the study, Southwest peony varieties group of Paeonia suffruticosa "Hongdan Lan" were analyzed, test was mainly divided into two parts, one is the nature of the low temperature, through the external environment is mainly (temperature, light) gibberellin and nutrition solution regulation, on the Tianpeng peony florescence control technological research. The second is to explore the flower forcing peony after anthesis regeneration technique. The main research results: comprehensive gibberellin peony flower induction of morphological and physiological indexes, such as gibberellin concentration of 150 mgFL and 200 mg/L the effect of flower induction was better than the other treatments; gibberelin (GA3) breaking the dormancy of the peony to blossom ahead of time has the promoter action, also has certain effect on nutritional growth; to premature flowering the abscisic acid (ABA) has opposite effect; whereas auxin (IAA) and corn (ZT) effect was not obvious; rejuvenation results showed that after a year of conservation and managemental measures, flower induction after the flower of peony played a very important role in the restoration. After the winter flower induction, peony flowerpot of soil hardening, through the soil replacement, repair of roots, flower peony recovery showed a very significant effect.
文摘To study the temporal and spatial changes of heat resources to serve agricultural production and economic development. The climate data from 1958 to 2017 were selected, and the temporal and spatial changes of heat resources in Liaoning, China were analyzed by using the method of climate diagnosis and analysis. The results show that: the southern coastal area of Liaoning has the most heat resources, the northwestern hilly area and the eastern mountainous area the least, and the central plain area in the middle distribution pattern;compared with 1958-1980, 1981-2017 ≥0°C, ≥10°C accumulated temperature, etc. The value line is advanced 100-160km northward. The accumulated temperature of ≥0°C and ≥10°C in Liaoning experienced abrupt changes in climate in 1993 and 1994, and the climate abrupt change in the southern coastal area was earlier than that in the inland. , the increase in the northwestern hilly area and the eastern mountainous area is less than that in the central plain area and the southern coastal area. The study on the impact on meteorological services found that the increase or decrease of heat resources has a significant impact on agro-meteorological services, which can prolong the growing season of crops, relatively reduce the damage of frost, improve comprehensive utilization of land, and increase crop yields;at the same time, with the increase of heat resources and the northward expansion of the isoline of accumulated temperature, the area affected by pests and diseases has expanded, which has aggravated the harm to agriculture economic burden.
基金National Basic Research Program of China(973 Program),No.2010CB951502The Fundamental Research Founds for Central Institutes(Chinese Academy of Tropical Agricultural Sciences(CATAS)),No.1630012012017,No.1630012013012,No.1630012014020+1 种基金Spark Research Program of China,No.2014GA 800006Key Science and Technology Research Program of Hainan Province,No.ZDXM2014082
文摘The spatial and temporal variations of ≥10℃ annual accumulated temperature (AAT10) were analyzed by using the linear trend line method, cumulative anomaly method and the multiple linear regression model (MLRM) interpolation method based on the daily meteorological observation data from 104 meteorological stations in Southern China and surrounding 39 meteorological stations from 1960 to 2011. The results show that: (1) From time scale point of view, the climatic trend of the AAT10 increased with an average of 7.54℃/decade in Southern China since 1960. The area of AAT10〈6000℃ decreased from 1960 to 2011, and the area of 6000℃〈AAT10〈8000℃ decreased from 1960 to 1979 and increased from 1980 to 2011, and the area of AAT10〉8000℃ increased from 1960 to 2011. (2) From spatial scale point of view, the AAT10 in Southern China reduced with increasing latitude and reduced with increasing altitude. The proportion of the area with 5000℃〈 AAT10〈8000℃ accounted for 70% of the study area, followed by the area of 4000℃〈AAT10 〈5000℃; and the area of AAT10〈4000℃ and AAT10〉8000℃ was the least. Climate trend rate of the AAT10 at 99% of the meteorological stations was greater than zero, which indicated that the AAT10 increased significantly in the central Yunnan province, southern Guangdong province as well as Hainan Island. (3) Comparison of period A (1960-1989) and period B (1980-2011) with the change of temperature zones shows that the boundaries of cool temperate zone, mid-temperate zone and warm temperate zone shifted northward and shrank westward. The northern boundary of north subtropical zone and mid-subtropical zone shifted northward gradually by over 0.5° and 0.5° latitude, respectively. The western part of northern boundary of south subtropical zone and marginal tropical zone shifted northward by 0.2° and 0.4° latitude, respectively. The change of temperature zones was expanded to high altitude and latitude. (4) The increase of the AAT10 is conducive to the production of tropical crops planted, which will increase the planting area that was suitable for tropical crops, and expand the planting boundaries to high latitude and high altitude.
基金supported by the National High Technology Research and Development Program (863) of China (No. 2012AA063406)the National Natural Science Foundation of China (No. 51008005)
文摘Temperature is an important physical factor, which strongly influences biomass and metabolic activity. In this study, the effects of temperature on the anoxic metabolism of nitrite (NO2) to nitrous oxide (N2O) by polyphosphate accumulating organisms, and the process of the accumulation of N2O (during nitrite reduction), which acts as an electron acceptor, were investigated using 91% :e 4% Candidatus Accumulibacterphosphatis sludge. The results showed that N2O is accumulated when Accumulibacter first utilize nitrite instead of oxygen as the sole electron acceptor during the denitrifying phosphorus removal process. Properties such as nitrite reduction rate, phosphorus uptake rate, N2O reduction rate, and polyhydroxyalkanoate degradation rate were all influenced by temperature variation (over the range from 10 to 30℃ reaching maximum values at 25℃). The reduction rate of N2O by N2O reductase was more sensitive to temperature when N2O was utilized as the sole electron acceptor instead of NO2, and the N2O reduction rates, ranging from 0.48 to 3.53 N2O-N/(hr.g VSS), increased to 1.45 to 8.60 mg N2O-N/(hr·g VSS). The kinetics processes for temperature variation of 10 to 30℃ were (01 = 1.140-1.216 and θ2 = 1.139-1.167). In the range of 10℃ to 30℃, almost all of the anoxic stoichiometry was sensitive to temperature changes. In addition, a rise in N2O reduction activity leading to a decrease in N2O accumulation in long term operations at the optimal temperature (27℃ calculated by the Arrhenius model).