The present work aims to assess the likely effects of climate change on the length of growing period (LGP) of crops in Marina Baixa (SE, Spain). LGP can be assessed by a balance between preci- pitation and reference e...The present work aims to assess the likely effects of climate change on the length of growing period (LGP) of crops in Marina Baixa (SE, Spain). LGP can be assessed by a balance between preci- pitation and reference evapotranspiration. Less rainfall and an increased evapotranspiration, forecast by Global Climate Models (GCMs), are considered as a high risk for agriculture. This area is located in a semiarid climate region where water is a very limited resource. It is a typical example of areas where the agricultural sector has to compete for water with the tourism industry. In this context, by using observed and projected precipitation data set (model HadCM3, Scenario A2), calculating reference evapotranspiration (ETo), and applying the frequency analysis of a probability-type method, we estimated the growing period length in the observed period (1961-1990) and three 30-year future periods (2011-40, 2041-70 and 2071-99) in the study area. The results show a drop in annual precipitations (-?30%) and an increased ETo (+18%) towards the end of this century with respect to the observed period (mean annual rainfall: 356 mm;mean ETo: 1476 mm). The results also show a decrease in the number of decades (10 days) when precipitation exceeds half of the ETo, which means shorter growing periods as the 21st century advances. This expected reduction in growing period length towards the end of the present century will imply that many rainfed crops, like olives, almonds and cereals, will require a higher irrigation water supply to maintain suitable growth and performance levels. The results are an early warning to manage water resources in Marina Baixa in a sustainable way.展开更多
The study aims to solve the problems of late transplanting rice with differ- ent seedling ages at the lower reaches of Yangtze River. We selected six varieties of different thermal and photo-response characteristics a...The study aims to solve the problems of late transplanting rice with differ- ent seedling ages at the lower reaches of Yangtze River. We selected six varieties of different thermal and photo-response characteristics as the test material to study the effect of different seedling ages on growth and yield of rice. The results showed that growing period of thermal-response rice was delayed by long seedling age, but less affected by the impact of photo-response rice; the yield of later thermal-re- sponse varieties with 25 days and 30 days seedling ages was significantly reduced. In contrast, the yield of early thermal-response varieties and later photo-response varieties were significantly reduced with 30 days seedling age. The optimal trans- planting seedling age was 15 days of thermal-response rice, while photo-response rice was 20 days. The thermal-response rice should be selected as early maturing varieties, while the photo-response rice could be selected as late maturing varieties for high yield.展开更多
Potato crop is the fourth main food crops in the world after maize, rice and wheat. It is characterized by specific temperature requirements and develops best at about 20°C. Forecasts of global warming prompt us ...Potato crop is the fourth main food crops in the world after maize, rice and wheat. It is characterized by specific temperature requirements and develops best at about 20°C. Forecasts of global warming prompt us to study the tolerance of potato genotypes to heat during the growing season. The aim of this work was to assess the response of chosen potato cultivars to high temperature during the different stages of plant growth under conditions of good soil moisture and drought. The impact of high temperature 32°C/25°C on potato plants was determined in pot experiment in three growth stages. A main measure of tolerance of the potato cultivars to high temperature during the growing season was an evaluation of the yield in relation to the Control combination. Here we demonstrated that tested potato cultivar’s response to high temperature during the growing season is dependent on the growth stage. The earlier it occurs, the more negative its impact on the growth and yield of potatoes is.展开更多
文摘The present work aims to assess the likely effects of climate change on the length of growing period (LGP) of crops in Marina Baixa (SE, Spain). LGP can be assessed by a balance between preci- pitation and reference evapotranspiration. Less rainfall and an increased evapotranspiration, forecast by Global Climate Models (GCMs), are considered as a high risk for agriculture. This area is located in a semiarid climate region where water is a very limited resource. It is a typical example of areas where the agricultural sector has to compete for water with the tourism industry. In this context, by using observed and projected precipitation data set (model HadCM3, Scenario A2), calculating reference evapotranspiration (ETo), and applying the frequency analysis of a probability-type method, we estimated the growing period length in the observed period (1961-1990) and three 30-year future periods (2011-40, 2041-70 and 2071-99) in the study area. The results show a drop in annual precipitations (-?30%) and an increased ETo (+18%) towards the end of this century with respect to the observed period (mean annual rainfall: 356 mm;mean ETo: 1476 mm). The results also show a decrease in the number of decades (10 days) when precipitation exceeds half of the ETo, which means shorter growing periods as the 21st century advances. This expected reduction in growing period length towards the end of the present century will imply that many rainfed crops, like olives, almonds and cereals, will require a higher irrigation water supply to maintain suitable growth and performance levels. The results are an early warning to manage water resources in Marina Baixa in a sustainable way.
基金Supported by State Science and Technology Supporting Program(2012BAD07B02)Special Program for Technological Development of Scientific Research Institute of Science and Technology Department(2013EG134237)"Three Rural and Six Party"Science and Technology Cooperation Projects of Zhejiang Province(SN201206)~~
文摘The study aims to solve the problems of late transplanting rice with differ- ent seedling ages at the lower reaches of Yangtze River. We selected six varieties of different thermal and photo-response characteristics as the test material to study the effect of different seedling ages on growth and yield of rice. The results showed that growing period of thermal-response rice was delayed by long seedling age, but less affected by the impact of photo-response rice; the yield of later thermal-re- sponse varieties with 25 days and 30 days seedling ages was significantly reduced. In contrast, the yield of early thermal-response varieties and later photo-response varieties were significantly reduced with 30 days seedling age. The optimal trans- planting seedling age was 15 days of thermal-response rice, while photo-response rice was 20 days. The thermal-response rice should be selected as early maturing varieties, while the photo-response rice could be selected as late maturing varieties for high yield.
文摘Potato crop is the fourth main food crops in the world after maize, rice and wheat. It is characterized by specific temperature requirements and develops best at about 20°C. Forecasts of global warming prompt us to study the tolerance of potato genotypes to heat during the growing season. The aim of this work was to assess the response of chosen potato cultivars to high temperature during the different stages of plant growth under conditions of good soil moisture and drought. The impact of high temperature 32°C/25°C on potato plants was determined in pot experiment in three growth stages. A main measure of tolerance of the potato cultivars to high temperature during the growing season was an evaluation of the yield in relation to the Control combination. Here we demonstrated that tested potato cultivar’s response to high temperature during the growing season is dependent on the growth stage. The earlier it occurs, the more negative its impact on the growth and yield of potatoes is.
