1901—2017年藏西南高原气候及其生产潜力时空变化

研究全球变暖背景下藏西南高原气候及气候生产潜力时空分布,对该区农牧业发展、生态保护和可持续发展等具有重要意义。基于1901—2017年的中国气象再分析数据,利用Miami和Thornthwaite Memorial模型对近117年藏西南高原气候变化、气候生产潜力的时空分布及影响因素进行了分析。结果表明：近117年来藏西南高原年均温呈上升趋势,年均降水量呈下降趋势,并存在明显周期和突变点;温度生产潜力呈增加趋势,空间上自东南向西北递减;降水、蒸散和标准生产潜力呈减小趋势,呈现自南向北递减的空间分布特征;标准生产潜力由降水和温度共同决定,降水是主要限制因子。未来气候若持续“暖干化”变化,将导致藏西南高原气候生产潜力下降。为促进畜牧业发展和生态环境的改善,未来应进一步推进退牧还草、人工种草、舍饲养殖等工程,并选用耐寒耐旱高产草种,提高牧草产量,实现草畜平衡,以推动传统畜牧业向现代牧业转变,实现草原生态保护和可持续发展。     

江苏省近40年农业干旱发生规律

利用１９６０年至１９９８年全省各站降水量、蒸散量和旱情记载等资料,研究确定了干旱指数计算的方法和不同季节的干旱指标。在此基础上,分析总结了江苏省近４０年来的农业干旱发生规律,发现９０年代以来江苏省秋旱发生概率呈上升趋势。     

基于GIS的华北高产粮区地下水硝态氮含量时空变异特征

集约化农业生产区地下水的硝酸盐污染是一个十分普遍的问题.选取华北平原典型高产粮区桓台县为研究对象,分别在2002年和2007年同一季节对该县境内的394个潜水水样和283个承压水水样的硝态氮含量进行了取样分析,应用地质统计学与GIS技术相结合的方法对其时空变异规律进行了分析.结果表明,2002年和2007年潜水硝态氮的平均含量分别为8.08 mg·L~(-1)和14.68 mg·L~(-1),承压水硝态氮的平均含量分别为3.87 mg·L~(-1)和7.19 mg·L~(-1),2007年比2002年含量增幅均接近1倍.2个时期承压水硝态氮含量的空间相关距离均远大于潜水硝态氮含量的相关距离.2007年与2002年相比,潜水硝态氮含量各等级(0～5、 5～10、 10～15、 15～20、 20～30和>30 mg·L~(-1))的面积变化幅度分别为-28.87%、 -14.63%、 13.06%、 14.37%、 12.23%和3.85%;承压水中前4个等级的面积变幅分别为-37.82%、 28.01%、 9.33%和0.48%.通过对地下水硝态氮含量的垂向分析发现,2个时期的承压水硝态氮含量与取样井深存在显著负相关关系,并且深层承压水的硝酸盐含量呈现上升趋势.     

闽东南特色农业生态模式研究

基于闽东南的资源优势,把发展亚热带水果作为特色农业。由于生态环境脆弱,必须寻求特色农业生产的最佳模式。本研究设计果农草牧复合系统作为特色农业的生态模式。试验表明:生态模式与传统模式相比,泥沙流失量仅是传统模式的26.3%和48.4%,0～20cm土层的有机质含量增加3.8g/kg和5.5g/kg。土地单位面积能量总产出是传统模式的5.1倍。本生态模式显示生产良好循环,取得有效的生态和经济效益,并有很好的发展前景。     

低碳经济与农业发展思考

大气中碳浓度的升高是导致全球气候变化的主要原因.以低能耗、低排放、低污染为特征的低碳经济是目前人类应对全球气候变化,减缓温室气体排放的根本出路.农业生产与全球气候变化息息相关,农业是温室气体的第二大重要来源,如何减少农业温室气体排放量并探寻减排方法已经成为当务之急.从低碳经济这一热点问题谈起,论述了农业生产与全球气候变化的关系,以及当前农业面临的问题和挑战,提出了发展低碳农业的对策以及具体措施,旨在为呼应低碳经济,应对全球气候变化提供科学决策,促进现代农业由高碳经济向低碳经济转型,实现农业的可持续发展.     

洞庭湖区的湖垸农业与可持续发展对策

在调查分析洞庭湖区围湖垦殖和湖垸农业形成的历史的基础上，归纳了湖垸农业面临的生态环境问题：洪涝灾害发生频率加大；水面减少，生物多样性降低；环境污染严重，湿地生态功能衰退；土壤退化和潜育化严重；血吸虫病死灰复燃。并结合已有的经验，提出了湖垸农业可持续发展的对策措施：认真实施生态保护工程，减少泥沙淤积；调整湖垸农业结构，建立有利于避灾、减灾新模式；退田还湖，发展替代农业，发展莲藕、籽藕、茭白等水生经济植物种植；与企业结合，发展油菜、马铃薯、亚麻等工业原料作物；利用欧美杨耐涝性强的特点，在地势较高的季节性淹没的洲滩地，发展以林为主的林农复合经营模式，湖洲草地发展草食畜禽替代模式。     

日喀则市农业生态足迹研究

采用水资源足迹和化石能源供给地概念,对日喀则市2005年农业活动的生态足迹进行实证分析.结果表明:日喀则市农业综合足迹为334 153.27 hm2,占日喀则市总足迹的77.6%,其中,化石能源地足迹仅占农业综合足迹的13.3%,表明农业现代化程度不高.对农业综合足迹贡献最大的是耕地和牧草地,二者合占65.6%,主要原因是大量使用农用化学品和牧草地严重超载;生产足迹占农业综合足迹的82.8%,说明农村占用的大部分资源主要用来进行资源再生产.对日喀则市农业综合足迹的实证研究表明,资源产量法可以有效减小土地面积法引起的生态赤字扩大化现象,将肉、蛋、奶产品作为次级产品更能反映牧草地利用现状.      

Heavy metal contamination and source in arid agricultural soil in central Gansu Province, China

Concentrations of copper （Cu）, lead （Pb）, chromium （Cr）, mercury （Hg）, and arsenic （As） were measured in arid agricultural and irrigated agricultural soils collected in Daba Village, Shajiawuan Village, Gangou Village and Sifangwu Village, located in central Gansu Province, China. Concentrations except Hg and Pb were lower than the background values in grey calcareous soil in the selected arid agricultural soils. Pb concentration exceeded the threshold of arid agricultural soils in China by 72.46%. These results showed that there was indeed serious pollution with Pb, a slight pollution problem for other selected metals in the irrigated agricultural soils in Daba Village. Principal component analysis （PCA） was used to assess the soil data, applying varimax rotation with Kaiser Normalization. The result showed that the irrigated factor, agricultural factor and anthropogenic factor all contributed to the relations between selected chemical properties. The main factor of accumulation of Cu, Pb, Cr, Hg and As was lithological factor in arid agricultural areas. There is a striking dissimilarity of origin of Cu, Pb, Cr, Hg and As in agricultural soil between the irrigate agriculture and arid agriculture.     

Work conditions in agriculture as risk factors of spinal pain in postmenopausal women

The aim of the study was to evaluate the risk factors for spinal pain in Polish postmenopausal women working in agriculture. The study included 1751 randomly selected postmenopausal women aged 45–65?years. The women were exposed to hazardous work conditions, in particular the use of force and heavy lifting, often more than 10?kg and with frequency of at least once a day. Two-thirds of them suffered from spinal pain, mostly in the lumbar spine and less frequently in the cervical and thoracic spine. The prevalence of spinal pain depended on exposure to health risks associated with overwork, early onset of menopause and increasing age. The prevalence of pain in the lumbar spine correlated positively with higher frequency of heavy lifting and using excessive force during agricultural work. The severity of spinal pain correlates positively with the age of pain onset and negatively with level of education.     

Mitigating the impact of oil‐palm monoculture on freshwater fishes in Southeast Asia

Anthropogenic land‐cover change is driving biodiversity loss worldwide. At the epicenter of this crisis lies Southeast Asia, where biodiversity‐rich forests are being converted to oil‐palm monocultures. As demand for palm oil increases, there is an urgent need to find strategies that maintain biodiversity in plantations. Previous studies found that retaining forest patches within plantations benefited some terrestrial taxa but not others. However, no study has focused on aquatic taxa such as fishes, despite their importance to human well‐being. We assessed the efficacy of forested riparian reserves in conserving freshwater fish biodiversity in oil‐palm monoculture by sampling stream fish communities in an oil‐palm plantation in Central Kalimantan, Indonesia. Forested riparian reserves maintained preconversion local fish species richness and functional diversity. In contrast, local and total species richness, biomass, and functional diversity declined markedly in streams without riparian reserves. Mechanistically, riparian reserves appeared to increase local species richness by increasing leaf litter cover and maintaining coarse substrate. The loss of fishes specializing in leaf litter and coarse substrate decreased functional diversity and altered community composition in oil‐palm plantation streams that lacked riparian reserves. Thus, a land‐sharing strategy that incorporates the retention of forested riparian reserves may maintain the ecological integrity of fish communities in oil‐palm plantations. We urge policy makers and growers to make retention of riparian reserves in oil‐palm plantations standard practice, and we encourage palm‐oil purchasers to source only palm oil from plantations that employ this practice.