How animals allocate their time to various activities has significant consequences for their survival because they reflect the different constraints on time-energy balances. Many ecological variables, such as day leng...How animals allocate their time to various activities has significant consequences for their survival because they reflect the different constraints on time-energy balances. Many ecological variables, such as day length, temperature, food availabil- ity, are supposed to effect on activity budgets allocation of temperate primates. To examine the potential influence of these three variables, the activity budgets ofRhinopithecus bieti was studied at Xiaochangdu, Tibet from June 2003 to March 2005. Pearson correlations were utilized to assess potential relationships between activity budget and day length, food availability and temperature, and stepwise multiple regressions to identify the priority of resting and other activities （activities besides feeding, moving and resting）. Time spent resting and doing ＂other activities＂ is positively related to day length, temperature and food availability. No significant correlations were found between feeding/moving time and any of these variables. This suggests that foraging time （feeding ＋ moving） takes priority over rest and other activities. Day length and foraging time （as independent variables） were related to the time spent in the other two activities besides feeding/moving （as dependent variables）. Both time spent resting and in ＂other activities＂ were highly significant positive functions of day length, with the latter a highly significant negative function of feeding time and moving time. Resting time may therefore be interpreted as taking priority over ＂other activities＂ time. These results provide further evidence of the importance of day length, temperature and food availability to seasonal activity budgets [Current Zoology 56 （6）： 650q559, 2010].展开更多
With the increase of global population,grain-population relationship has attracted great attention worldwide.In China,grain-population relationship has become an increasingly important economic concern.Of central impo...With the increase of global population,grain-population relationship has attracted great attention worldwide.In China,grain-population relationship has become an increasingly important economic concern.Of central importance to the food security debate in China is the geography of grain supply and demand.This paper uses a grain demand and supply index (DSR) to analyze the spatial-temporal relationship between population and grain in China from 1949 to 2007 at national and provincial scales.The results are examined in three periods.(1) From 1949 to 2007,with the increase of grain production,the relationship between population and grain of China improved considerably.(2) Over the past 35 years (1970-2005),on the whole the grain producing areas have had grain surplus and contributed to the nation by providing grain,but the ability to provide sufficient grain is not stable.(3) Over the past 15 years (1990-2005),decreases in planting area brought pressure on national grain food security.The paper concludes that the key to providing more food for the main food producing provinces is increasing yield on the basis of steady plant area.展开更多
Global food supply has for a long time been regarded as only a problem of food production. Since the turn of the century, however, other aspects have entered the debate, such as improving food quality, changing eating...Global food supply has for a long time been regarded as only a problem of food production. Since the turn of the century, however, other aspects have entered the debate, such as improving food quality, changing eating habits and avoiding food waste. The latter topic has become the subject of attention for the past I0 years and the interest in it has steadily grown. This paper focuses on food waste within the overall context. Apart from the purely quantitative （material） aspects, it draws our attention to the immaterial side of waste, which has to do with our value system. It hopes to sharpen our minds towards a responsible way of dealing with resources展开更多
Most Japanese are enjoying rich and convenient dietary habits nowadays. However, majorities of Japanese are feeling anxiety about the future food supply because Japan＇s food self-sufficiency ratio has fallen most rap...Most Japanese are enjoying rich and convenient dietary habits nowadays. However, majorities of Japanese are feeling anxiety about the future food supply because Japan＇s food self-sufficiency ratio has fallen most rapidly in the last 45 years, and is lowest amongst countries with a population of more than 100 million. Major causes and mechanisms of the decline in the food self-sufficiency ratio over the last 45 years were analyzed. Drastic changes of dietary habits under rapid economic growth and sharp appreciation of the yen against the US dollar were found to be the major causes of the sharp decline of the food self-sufficiency ratio. Preliminary projections about the food self-sufficiency ratio in 2015 were carried out, and it was found that it will not be easy to achieve the policy goal of raising the food self-sufficiency ratio to 45% by 2015.展开更多
The goal of this study was to investigate the behaviour of rainbow trout(n=30),Oncorhynchus mykiss,in small raceways when either self-feeders(T2) or hand-feeding(t2) were used.The method of food delivery in T2 was def...The goal of this study was to investigate the behaviour of rainbow trout(n=30),Oncorhynchus mykiss,in small raceways when either self-feeders(T2) or hand-feeding(t2) were used.The method of food delivery in T2 was defensible while that of t2 was indefensible.Fish in both raceways were subjected to restricted feeding(RF) for 25 days.Food was available in the morning(09:00-10:00) in the downstream area and in the afternoon(16:00-17:00) in the upstream area of the raceways.The results showed that the behaviour of rainbow trout was significantly different under interference competition(T2) for food compared with that under scramble competition(t2).RF in T2 fish limited food availability to meal times when feeding rewards were available while t2 fish only responded to the location of food delivery.The aggressive fish in T2 were dominant,and t2 fish at high densities showed intense social interactions under the indefensible pattern of food distribution;these interactions did not dampen to a minimum level to suppress the development of dominance hierarchies.Further,the stocking density did not break down the dominance hierarchies between the T2 fish.This suggests that decreased efficiency in the search for food or inefficient foraging,induced by interference competition at high densities,affected the behaviour of rainbow trout.展开更多
The resultant climate change on sustainable food supply has greatly affected agricultural production by the level of great volumes of gasses emitted into the atmosphere by human activities. The human factors that emit...The resultant climate change on sustainable food supply has greatly affected agricultural production by the level of great volumes of gasses emitted into the atmosphere by human activities. The human factors that emit large amount of green house gases include industrialization, burning of fossil fuel and gas flaring. Increase in air temperature and consequent increase in the rates of evaporation also affect the level of food supply. Data for this study were collected from primary and secondary sources. Primary source were collected through field investigation and structured questionnaire. A total of 450 questionnaires were administered. Results revealed that varieties of crops ranging from tree crops to cereals were cultivated within the study area. The effect of climate change on food supply has resulted into change in crop yields, change in rainfall pattern, soil loss and has greatly affected planting period and harvesting. The study therefore recommended awareness campaigns on the causes and consequences of global climate change on food production, environmental education and afforestation campaign programmes on sustainable food supply and environmental safety must be intensified.展开更多
This scientific study focuses on the economic and especially the psychosocial factors of success in negotiation processes between buyers （procurers） and suppliers （producers） in the food trade. In particular, it e...This scientific study focuses on the economic and especially the psychosocial factors of success in negotiation processes between buyers （procurers） and suppliers （producers） in the food trade. In particular, it examines the economic and mental satisfaction in the decision-making and in the negotiation processes for efficient food supply. It is examined primarily as transparency in addition to Harvard concept at annual meetings （or between the year） favoring a satisfactory result for both negotiators. In a structural equation model, the Harvard negotiating points are brought with transparency in communication and this in terms of economic success experiences and the sociomental satisfaction.展开更多
Biofuels are the current promising alternative to fossil fuels. However, the fluctuating food prices caused by oil price led to critics to biofuels. The paper surveyed biofuels production and grain production and cons...Biofuels are the current promising alternative to fossil fuels. However, the fluctuating food prices caused by oil price led to critics to biofuels. The paper surveyed biofuels production and grain production and consumption demand, and come to the conclusion that there was a little impact of corn ethanol on international food price, and there was no impact on China’s food prices. China has launched non-food biofuels development strategy to use marginal lands for growing hard crops, such as sweet sorghum, tuber crops, and switchgrass etc. to produce biofuels without any impact on food security in the future.展开更多
China's macro economy has remained in a good and stable condition overall,experiencing an annual GDP growth of over 10% for several consecutive years.Under this basic condition, the main focus of the Outlook was C...China's macro economy has remained in a good and stable condition overall,experiencing an annual GDP growth of over 10% for several consecutive years.Under this basic condition, the main focus of the Outlook was China's current grain and oil supply,and the demand market with its probable future prices.展开更多
Models of adaptive behaviour typically assume that animals behave as though they have highly complex, detailed strategies for making decisions. In reality, selection favours the optimal balance between the costs and b...Models of adaptive behaviour typically assume that animals behave as though they have highly complex, detailed strategies for making decisions. In reality, selection favours the optimal balance between the costs and benefits of complexity. Here we investigate this trade-off for an animal that has to decide whether or not to forage for food - and so how much energy reserves to store - depending on the food availability in its environment. We evolve a decision rule that controls the target reserve level for different ranges of food availability, but where increasing complexity is costly in that metabolic rate increases with the sensitivity of the rule. The evolved rule tends to be much less complex than the optimal strategy but performs almost as well, while being less costly to implement. It achieves this by being highly sensitive to changing food availability at low food abun- dance - where it provides a close fit to the optimal strategy - but insensitive when food is plentiful. When food availability is high, the target reserve level that evolves is much higher than under the optimal strategy, which has implications for our under- standing of obesity. Our work highlights the important principle of generalisability of simple decision-making mechanisms, which enables animals to respond reasonably well to conditions not directly experienced by themselves or their ancestors.展开更多
Migratory birds rely on fueling prior to migratory flights. Fueling in migrants is controlled by intrinsic as well as ex- trinsic factors. From captive studies we have started understanding the internal mechanisms con...Migratory birds rely on fueling prior to migratory flights. Fueling in migrants is controlled by intrinsic as well as ex- trinsic factors. From captive studies we have started understanding the internal mechanisms controlling bird migration. Field studies have demonstrated the effects of external factors, such as food availability, weather, competitors, parasites or diseases, on the stopover behavior of migrants. However, an integrated approach is still missing to study coherently how the innate migration program interacts with the varying environmental cues and to estimate the contribution of the innate migration program and the environment to realized migration. The northern wheatear Oenanthe oenanthe offers a unique opportunity for integrated studies. It breeds across almost the whole Holarctic with just a ＂gap＂ between eastern Canada and Alaska. All breeding populations over- winter in sub-Saharan Africa which makes the northern wheatear one of the most long-distant migratory songbirds with extraor- dinary long non-stop flights across oceans. It is a nocturnal migrant which travels without parental or social aid/guidance. Thus, young birds rely entirely on endogenous mechanisms of timing, route selection and fueling on their first outbound migration. By establishing indoor housing under controlled conditions the endogenous control mechanisms of northern wheatear migration could be revealed. At the same time, environmental factors controlling fueling could be investigated in the field. On migration wheatears occur in a variety of habitats with sparse vegetation where their stopover behavior could be quantitatively studied in the light of ＂optimal migration＂ theory by the use of remote balances, radio-tagging and even experimentally manipulated food availability. The present paper summarizes our approach to understand the control of migration in northern wheatears by combin- ing field and laboratory studies at various spatial and temporal scales, and linking various sub-disciplines .展开更多
基金supported by the Chinese Academy of Sciences (KSCX2-1-09)the National Natural Science Foundation of China (30870375,31071937)
文摘How animals allocate their time to various activities has significant consequences for their survival because they reflect the different constraints on time-energy balances. Many ecological variables, such as day length, temperature, food availabil- ity, are supposed to effect on activity budgets allocation of temperate primates. To examine the potential influence of these three variables, the activity budgets ofRhinopithecus bieti was studied at Xiaochangdu, Tibet from June 2003 to March 2005. Pearson correlations were utilized to assess potential relationships between activity budget and day length, food availability and temperature, and stepwise multiple regressions to identify the priority of resting and other activities （activities besides feeding, moving and resting）. Time spent resting and doing ＂other activities＂ is positively related to day length, temperature and food availability. No significant correlations were found between feeding/moving time and any of these variables. This suggests that foraging time （feeding ＋ moving） takes priority over rest and other activities. Day length and foraging time （as independent variables） were related to the time spent in the other two activities besides feeding/moving （as dependent variables）. Both time spent resting and in ＂other activities＂ were highly significant positive functions of day length, with the latter a highly significant negative function of feeding time and moving time. Resting time may therefore be interpreted as taking priority over ＂other activities＂ time. These results provide further evidence of the importance of day length, temperature and food availability to seasonal activity budgets [Current Zoology 56 （6）： 650q559, 2010].
基金financial support from Education Bureau of Shandong for the research as visiting scholar in the University of Sydney
文摘With the increase of global population,grain-population relationship has attracted great attention worldwide.In China,grain-population relationship has become an increasingly important economic concern.Of central importance to the food security debate in China is the geography of grain supply and demand.This paper uses a grain demand and supply index (DSR) to analyze the spatial-temporal relationship between population and grain in China from 1949 to 2007 at national and provincial scales.The results are examined in three periods.(1) From 1949 to 2007,with the increase of grain production,the relationship between population and grain of China improved considerably.(2) Over the past 35 years (1970-2005),on the whole the grain producing areas have had grain surplus and contributed to the nation by providing grain,but the ability to provide sufficient grain is not stable.(3) Over the past 15 years (1990-2005),decreases in planting area brought pressure on national grain food security.The paper concludes that the key to providing more food for the main food producing provinces is increasing yield on the basis of steady plant area.
文摘Global food supply has for a long time been regarded as only a problem of food production. Since the turn of the century, however, other aspects have entered the debate, such as improving food quality, changing eating habits and avoiding food waste. The latter topic has become the subject of attention for the past I0 years and the interest in it has steadily grown. This paper focuses on food waste within the overall context. Apart from the purely quantitative （material） aspects, it draws our attention to the immaterial side of waste, which has to do with our value system. It hopes to sharpen our minds towards a responsible way of dealing with resources
文摘Most Japanese are enjoying rich and convenient dietary habits nowadays. However, majorities of Japanese are feeling anxiety about the future food supply because Japan＇s food self-sufficiency ratio has fallen most rapidly in the last 45 years, and is lowest amongst countries with a population of more than 100 million. Major causes and mechanisms of the decline in the food self-sufficiency ratio over the last 45 years were analyzed. Drastic changes of dietary habits under rapid economic growth and sharp appreciation of the yen against the US dollar were found to be the major causes of the sharp decline of the food self-sufficiency ratio. Preliminary projections about the food self-sufficiency ratio in 2015 were carried out, and it was found that it will not be easy to achieve the policy goal of raising the food self-sufficiency ratio to 45% by 2015.
文摘The goal of this study was to investigate the behaviour of rainbow trout(n=30),Oncorhynchus mykiss,in small raceways when either self-feeders(T2) or hand-feeding(t2) were used.The method of food delivery in T2 was defensible while that of t2 was indefensible.Fish in both raceways were subjected to restricted feeding(RF) for 25 days.Food was available in the morning(09:00-10:00) in the downstream area and in the afternoon(16:00-17:00) in the upstream area of the raceways.The results showed that the behaviour of rainbow trout was significantly different under interference competition(T2) for food compared with that under scramble competition(t2).RF in T2 fish limited food availability to meal times when feeding rewards were available while t2 fish only responded to the location of food delivery.The aggressive fish in T2 were dominant,and t2 fish at high densities showed intense social interactions under the indefensible pattern of food distribution;these interactions did not dampen to a minimum level to suppress the development of dominance hierarchies.Further,the stocking density did not break down the dominance hierarchies between the T2 fish.This suggests that decreased efficiency in the search for food or inefficient foraging,induced by interference competition at high densities,affected the behaviour of rainbow trout.
文摘The resultant climate change on sustainable food supply has greatly affected agricultural production by the level of great volumes of gasses emitted into the atmosphere by human activities. The human factors that emit large amount of green house gases include industrialization, burning of fossil fuel and gas flaring. Increase in air temperature and consequent increase in the rates of evaporation also affect the level of food supply. Data for this study were collected from primary and secondary sources. Primary source were collected through field investigation and structured questionnaire. A total of 450 questionnaires were administered. Results revealed that varieties of crops ranging from tree crops to cereals were cultivated within the study area. The effect of climate change on food supply has resulted into change in crop yields, change in rainfall pattern, soil loss and has greatly affected planting period and harvesting. The study therefore recommended awareness campaigns on the causes and consequences of global climate change on food production, environmental education and afforestation campaign programmes on sustainable food supply and environmental safety must be intensified.
文摘This scientific study focuses on the economic and especially the psychosocial factors of success in negotiation processes between buyers （procurers） and suppliers （producers） in the food trade. In particular, it examines the economic and mental satisfaction in the decision-making and in the negotiation processes for efficient food supply. It is examined primarily as transparency in addition to Harvard concept at annual meetings （or between the year） favoring a satisfactory result for both negotiators. In a structural equation model, the Harvard negotiating points are brought with transparency in communication and this in terms of economic success experiences and the sociomental satisfaction.
文摘Biofuels are the current promising alternative to fossil fuels. However, the fluctuating food prices caused by oil price led to critics to biofuels. The paper surveyed biofuels production and grain production and consumption demand, and come to the conclusion that there was a little impact of corn ethanol on international food price, and there was no impact on China’s food prices. China has launched non-food biofuels development strategy to use marginal lands for growing hard crops, such as sweet sorghum, tuber crops, and switchgrass etc. to produce biofuels without any impact on food security in the future.
文摘China's macro economy has remained in a good and stable condition overall,experiencing an annual GDP growth of over 10% for several consecutive years.Under this basic condition, the main focus of the Outlook was China's current grain and oil supply,and the demand market with its probable future prices.
文摘Models of adaptive behaviour typically assume that animals behave as though they have highly complex, detailed strategies for making decisions. In reality, selection favours the optimal balance between the costs and benefits of complexity. Here we investigate this trade-off for an animal that has to decide whether or not to forage for food - and so how much energy reserves to store - depending on the food availability in its environment. We evolve a decision rule that controls the target reserve level for different ranges of food availability, but where increasing complexity is costly in that metabolic rate increases with the sensitivity of the rule. The evolved rule tends to be much less complex than the optimal strategy but performs almost as well, while being less costly to implement. It achieves this by being highly sensitive to changing food availability at low food abun- dance - where it provides a close fit to the optimal strategy - but insensitive when food is plentiful. When food availability is high, the target reserve level that evolves is much higher than under the optimal strategy, which has implications for our under- standing of obesity. Our work highlights the important principle of generalisability of simple decision-making mechanisms, which enables animals to respond reasonably well to conditions not directly experienced by themselves or their ancestors.
文摘Migratory birds rely on fueling prior to migratory flights. Fueling in migrants is controlled by intrinsic as well as ex- trinsic factors. From captive studies we have started understanding the internal mechanisms controlling bird migration. Field studies have demonstrated the effects of external factors, such as food availability, weather, competitors, parasites or diseases, on the stopover behavior of migrants. However, an integrated approach is still missing to study coherently how the innate migration program interacts with the varying environmental cues and to estimate the contribution of the innate migration program and the environment to realized migration. The northern wheatear Oenanthe oenanthe offers a unique opportunity for integrated studies. It breeds across almost the whole Holarctic with just a ＂gap＂ between eastern Canada and Alaska. All breeding populations over- winter in sub-Saharan Africa which makes the northern wheatear one of the most long-distant migratory songbirds with extraor- dinary long non-stop flights across oceans. It is a nocturnal migrant which travels without parental or social aid/guidance. Thus, young birds rely entirely on endogenous mechanisms of timing, route selection and fueling on their first outbound migration. By establishing indoor housing under controlled conditions the endogenous control mechanisms of northern wheatear migration could be revealed. At the same time, environmental factors controlling fueling could be investigated in the field. On migration wheatears occur in a variety of habitats with sparse vegetation where their stopover behavior could be quantitatively studied in the light of ＂optimal migration＂ theory by the use of remote balances, radio-tagging and even experimentally manipulated food availability. The present paper summarizes our approach to understand the control of migration in northern wheatears by combin- ing field and laboratory studies at various spatial and temporal scales, and linking various sub-disciplines .
