A2和B2排放情景下气候变化对福建省水稻生产的阶段性影响

选择IPCC排放情景特别报告(SRES)中的A2和B2方案,利用区域气候模式PRECIS构建的气候变化情景文件与作物模型(CERES-Rice)耦合,采用雨养与灌溉两种方式,并综合考虑未来CO2浓度增加带来的直接增益效应,模拟了未来2020s及2040s两个时段气候变化对福建省水稻生育期与产量的影响。结果表明:无论是雨养方式还是灌溉方式,未来全省各稻区水稻生育期都将缩短,并且随着温度增高,2040s时段缩短的时间较2020s更长,单季稻生育期缩短时间最长,可达15~20 d。雨养条件下,除了闽东南双季稻区后季稻在2020s时段表现为2.3%(A2)和3.1%(B2)较小幅度的增产外,其他稻区各种稻作制度下的水稻产量较之BASE均出现了不同幅度的减产。闽西北稻区后季稻减产幅度最大,2020s时段A2和B2情景下减产幅度依次为6.9%和10.2%,2040s时段减产幅度进一步加大至14.1%和15.6%。闽东南稻区后季稻模拟结果较为乐观,尤其是在灌溉条件下表现为不同幅度的增产,两种情景下分别增产了1.7%、3.9%。双季稻种植区的后季稻产量稳定性均不如早稻和单季稻的,且随着温度升高,到2040s产量不稳定性有增加的趋势。灌溉在一定程度上可以缓解未来高温天气带来的产量波动。从全省的总产变化趋势来看,A2和B2两种排放情景模拟的结果都不容乐观,即使采用充分灌溉的方式,也依旧表现为减产。2020s时段,两种情景下分别减产0.74%与2.44%;2040s时段,两种情景下减产为3.50%与3.23%。未来早稻和单季稻生长季的土壤水分条件将变得不如目前湿润,与之相关的灌溉需要量均有所增加。     

"全球农情遥感速报系统(CropWatch)"新进展

目前由中国科学院遥感应用研究所建设和运行的"全球农情遥感速报系统",是世界上开展全球尺度农情遥感业务监测的主要运行系统之一,可以在中国和全球尺度提供作物长势、单产、种植面积、产量和旱情等农情信息.自1998年建设至今,已经发展成为一个独立运行、监测内容全面、技术先进、监测结果可靠,并具有快速响应能力的系统.2004年,<遥感学报>(第8卷第6期)对该系统的主要技术方法进行了系统介绍.2005-2009年,通过对CropWatch的不断完善,提高了系统的独立性和运行效率,并在2008年春季雪灾、汶川地震、2009年冬小麦种植区春季干旱、2010年西南大旱等关键时期发挥了重要作用.详细介绍了2005-2009年间在系统化建设、监测的独立性和系统的应用推广等方面的进展,并对系统在"十二五"期间的发展重点进行了展望.     

Changes in Land Use and Agricultural Production Structure Before and After the Implementation of Grain for Green Program in Western China–Taking Two Typical Counties as Examples

Soil erosion becomes a serious environmental problem in the world, especially in western China. An effective management practice called the Grain for Green Program （GGP）, which was launched in 1999, aims to reduce soil and water loss and alleviate the ecological environment problem in western China. Two typical counties in western China, the Zhongxian （in Chongqing Municipality） and Ansai （in Shaanxi Province） were chosen to evaluate the dynamic changes of land use and agricultural production structure before and after the implementation of the Program in this paper. The results showed that the cultivated land area was reduced by 7.08% from 1989 to 2003. The cultivated land per person was decreased by 8.42% during 1999-2003. Moreover, the stability index of the secondary sector of the economy was increased from 0.91 in the period 1990-1999 to 0.94 in the following ten years. In addition, the stability index of tertiary economic sector increased from 0.88 to 0.92 in Zhongxian county. Meanwhile, the cultivated land area was reduced by 15.48% from 1990 to 1999. The soil erosion modulus was decreased by 33.33% from 1999 to 2006. Also, the stability index of secondary and tertiary economic sectors was 0.86 in the period 1998-2002. However, it decreased by 77% during 2002 to 2007 in Ansai County. These results imply that the Grain for Green Program had different impact on the two regions. Several effective strategies of soil and water conservation have been carried out to ameliorate the sustainable development of ecological environment and economy in these two counties of western China.     

The Role of Coffee in the Development of Southwest Ethiopia's Forests: Farmers' Strategies,Investor Speculation,and Certification Projects

This article examines the role of coffee in the agriculture of southwest Ethiopian highlands, a context characterized by recent huge private coffee estate developments, coffee certification projects and smallholdings. The analysis shows that smallholder farmers prioritize staple crops, and allocate land and labor to coffee only once food production objectives have been reached. It also underscores the diversity of the local peasantry, often treated as a homogeneous group in development projects designed to boost farmers' income through coffee production. Based on this analysis, the article evaluates the effects of recent coffee-oriented development policies: state forest concessions for coffee investment, and two coffee certification projects (UTZ-Certified and Fair-Trade/Organic). Because they omit the differentiated farmers' strategies, these certification initiatives fail to improve local populations' livelihoods and accelerate incipient socioeconomic inequalities. Moreover, when applied to big private plantations, they participate in farmers' dispossession from critical forest resources essential to households' food self-sufficiency.     

Egg production rates of two common copepods in the Barents Sea in summer

Small copepod species play important roles in the pelagic food webs of the Arctic Ocean, linking primary producers to higher trophic levels. The egg production rates (EPs) and weight-specific egg production rates (SEPs) of two common copepods, Acartia longiremis and Temora longicornis, were studied under experimental conditions in Dalnezelenetskaya Bay (southern Barents Sea) during summer. The average EP and SEP at 5–10 °C were 4.7 ± 0.4 eggs female⁻¹ day⁻¹ and 0.025 ± 0.002 day⁻¹, respectively, for A. longiremis and 13.1 ± 0.9 eggs female⁻¹ day⁻¹ and 0.075 ± 0.006 day⁻¹, respectively, for T. longicornis. EP and SEP were significantly higher at 10°C than at 5°C for both species. The mean egg diameter correlated positively and significantly with female prosome length (PL) in each species. SEP of T. longicornis correlated negatively and significantly with PL. Daily EP and SEP were similar to rates recorded for other Acartia and Temora species in temperate and warm regions. The influence of environmental factors (temperature, salinity, and phytoplankton concentration) on EP of both species is discussed. We conclude that temperature is the main factor determining the reproduction rate and timing in A. longiremis and T. longicornis in the Barents Sea.     

Layered farming for Marsupenaeus japonicus Bate

Marsupenaeusjaponicus Bate is one of the most valuable cultured shrimp species in China and outdoor earthen pond farming is the most common method of culturing this organism. The need to increase soil usage efficiency in aquaculture has been recognized and a great deal of research effort has been directed toward development of super-intensive farming systems. However, current research and development in this field is largely devoted to Litopenaeus vannamei Boone, while to M.japonicus Bate it has been neglected. In this study, a layered fanning system was designed and a 66-day study was conducted in M.japonicus Bate culture. The system comprised bracket and sand layers that divided a shrimp tank filled to a depth of 1.2 m into four water layers. Conventional tank culture （unlayered） was used as a control. The results show that survival rate, feed conversion efficiency and production of M.japonicus Bate in the layered farming system were 68%, 18%, and 0.59 kg/m^2, respectively, all of which are significantly higher than in the unlayered fanning system （P〈0.01）. These findings confirmed the possibility of using a layered system to culture M. japonicus Bate.     

The Soil Moisture and Net Primary Production Affected by CO_2 and Climate Change Using a Coupled Model

In this paper, a coupled model was used to estimate the responses of soil moisture and net primary production of vegetation （NPP） to increasing atmospheric CO2 concentration and climate change. The analysis uses three experiments simulated by the second-generation Earth System Model （CanESM2） of the Canadian Centre for Climate Modelling and Analysis （CCCma）, which are part of the phase 5 of the Coupled Model Intercomparison Project （CMIP5）. The authors focus on the magnitude and evolution of responses in soil moisture and NPP using simulations modeled by CanESM, in which the individual effects of increasing CO2 concentration and climate change and their combined effect are separately accounted for. When considering only the single effect of climate change, the soil moisture and NPP have a linear trend of 0.03 kg m^-2 yr^-1 and-0.14 gC m^- 2 yr^-2, respec- tively. However, such a reduction in the global NPP results from the decrease of NPP at lower latitudes and in the Southern Hemisphere, although increased NPP has been shown in high northern latitudes. The largest negative trend is located in the Amazon basin at -1.79 gC m^-2 yr^-2. For the individual effect of increasing CO2 concentration, both soil moisture and NPP show increases, with an elevated linear trend of 0.02 kg m^-2 yr^-1 and 0.84 gC m^-2 yr^-2, respectively. Most regions show an increasing NPP, except Alaska. For the combined effect of increasing atmospheric CO2 and climate change, the increased soil moisture and NPP exhibit a linear trend of 0.04 kg m^2 yr^-1 and 0.83 gC m^2 yr^-2 at a global scale. In the Amazon basin, the higher reduction in soil moisture is illustrated by the model, with a linear trend of-0.39 kg m^-2 yr^-1, for the combined effect. Such a change in soil moisture is caused by a weakened Walker circulation simulated by this coupled model, compared with the single effect of increasing CO2 concentration （experiment M2）, and a consequence of the reduction in NPP is also shown in this area, with a linear trend of-     

An exploration for deep-sea fish sounds off Vancouver Island from the NEPTUNE Canada ocean observing system

Our understanding of the significance of sound production to the ecology of deep-sea fish communities has improved little since anatomical surveys in the 1950s first suggested that sound production is widespread among slope-water fishes. The recent implementation of cabled ocean observatory networks around the world that include passive acoustic recording instruments provides scientists an opportunity to search for evidence of deep-sea fish sounds. We examined deep-sea acoustic recordings made at the NEPTUNE Canada Barkley Canyon Axis Pod (985 m) located off the west coast of Vancouver Island in the Northeast Pacific between June 2010 and May 2011 to determine the presence of fish sounds. A subset of over 300 5-min files was examined by selecting one day each month and analyzing one file for each hour over the 24 h day. Despite the frequent occurrence of marine mammal sounds, no examples of fish sounds were identified. However, we report examples of isolated unknown sounds that might be produced by fish, invertebrates, or more likely marine mammals. This finding is in direct contrast to recent smaller studies in the Atlantic where potential fish sounds appear to be more common. A review of the literature indicates 32 species found off British Columbia that potentially produce sound could occur in depths greater than 700 m but of these only Anoplopoma fimbria and Coryphaenoides spp. have been previously reported at the site. The lack of fish sounds observed here may be directly related to the low diversity and abundance of fishes present at the Barkley Canyon site. Other contributing factors include possible masking of low amplitude biological signals by self-generated noise from the platform instrumentation and ship noise. We suggest that examination of data both from noise-reduced ocean observatories around the world and from dedicated instrument surveys designed to search for deep-sea fish sounds to provide a larger-scale, more conclusive investigation into the role, or potential lack thereof, of sound production.     

The potential of the greenness and radiation (GR) model to interpret 8-day gross primary production of vegetation

Remote sensing of vegetation gross primary production (GPP) is an important step to analyze terrestrial carbon (C) cycles in response to changing climate. The availability of global networks of C flux measurements provides a valuable opportunity to develop remote sensing based GPP algorithms and test their performances across diverse regions and plant functional types (PFTs). Using 70 global C flux measurements including 24 non-forest (NF), 17 deciduous forest (DF) and 29 evergreen forest (EF), we present the evaluation of an upscaled remote sensing based greenness and radiation (GR) model for GPP estimation. This model is developed using enhanced vegetation index (EVI) and land surface temperature (LST) from the Moderate Resolution Imaging Spectroradiometer (MODIS) and global course resolution radiation data from the National Center for Environmental Prediction (NCEP). Model calibration was achieved using statistical parameters of both EVI and LST fitted for different PFTs. Our results indicate that compared to the standard MODIS GPP product, the calibrated GR model improved the GPP accuracy by reducing the root mean square errors (RMSE) by 16%, 30% and 11% for the NF, DF and EF sites, respectively. The standard MODIS and GR model intercomparisons at individual sites for GPP estimation also showed that GR model performs better in terms of model accuracy and stability. This evaluation demonstrates the potential use of the GR model in capturing short-term GPP variations in areas lacking ground measurements for most of vegetated ecosystems globally.