新疆牧草生产现状、市场分析与产业化途径

草业在国民经济和生态环境中具有重要的地位和作用。新疆草产业在技术水平、资金投入、经营方式与理念上,与兄弟行业相比都存在着较大差距,与兄弟省区和发达国家比较,差距更加明显。草产业的发展必须融入市场、必须走产业化道路。草业要提升发展层次,适应自治区发展现代畜牧业的新势头,应当强化草业行政管理;加大财政支持力度;制定优惠政策、扶持龙头企业;建立农牧民自己的合作组织;提高草业生产的科技含量,重视优良牧草种子的生产和推广。     

ENERGY BALANCE OF A CORN RESIDUE-COVERED FIELD DURING SNOWMELT1

ABSTRACT: Transport of agricultural chemicals in runoff and recharge waters from snowmelt and soil thawing may represent a significant event in terms of annual contaminant loadings in temperate regions. Improved understanding of the melt dynamics of shallow snowpacks is necessary to fully assess the implications for water quality. The objective of this study was to measure the energy balance components of a corn (Zea mays L.) stubble field during the melting of its snowcover. Net radiation (Rn), soil (G), sensible (H), and latent (Q) heat fluxes were measured in a field near Ames, Iowa, during the winter of 1994–1995. Energy consumed by melting including change in energy storage of the snowpack was determined as the residual of the measured energy balance. There was continuous snowcover at the field site for 71 days (maximum depth = 222 mm) followed by an open period of 11 days before additional snowfall and a second melt period. The net radiation and snow melt/energy storage change (5) terms dominated the energy balance during both measurement intervals. Peak daily sensible and latent heat fluxes were below 100 W m^?2 on all days except the last day of the second melt period. There was good agreement between predicted and measured values of H and Q during the melting of an aged snow layer but poorer agreement during the melt of fresh snow. Both snowpacks melted rapidly and coincident changes in soil moisture storage were observed. Improved estimates of Q and H, especially for partially open surfaces, will require better characterization of the surface aerodynamic properties and spatially-representative surface temperature measurements.     

近郊丘陵谷地高效农业综合开发研究

在剖析近郊丘陵谷地资源优势及利用问题的基础上，应用生态学和系统论原理及方法，以市场为导向，进行谷地资源的多目标线性规划，通过对区域系统物质循环、能量转化及经济效益的分析，提出“以鱼鸭结合为龙头，稳定果园面积，发展高效种植业”的总体规划方案，采取低产幼龄果园改良、名特优苗木繁育、池塘高产养殖和建立高效种植制度等技术措施，对谷地资源实行立体动态综合开发，建立较稳定的近郊丘陵谷地人工农业生态系统，取得显著的经济、社会和生态效益。     

全球CO2倍增对我国自然地域分异及农业生产潜力的影响预测

ＣＯ_２倍增导致全球变暖,并对自然环境产生影响的研究已成为举世瞩目的重大课题。本文在ＩＰＣＣ预告的基础上,分析了气候变化对我国自然地域分异的影响,用６７１个站点资料分析了我国温度带及各自然地区的数量指标、各地区生产潜力及影响生产潜力的因子,将气候变暖增温、温度带北移的界线及降水区向西迁移后干湿地区界线的变化绘制成图,同时预测了农业生产潜力的未来变化。结果表明：全球变暖使我国温暖地区面积增加,半干旱及干旱区水分条件改善,有利于作物生产。     

我国热带地区胶-茶-鸡农林复合系统物质循环研究

以海南省文昌市典型的胶-茶-鸡农林复合模式为研究对象 ,以单作胶园、胶茶间作园为对照 ,采用定量研究与定性分析相结合的方法 ,研究其物质循环规律。结果表明 ,胶-茶-鸡农林复合系统的氮、磷输入、输出量最大 ,系统外物质投入率比另两系统明显减少 ,系统内养分循环量增加 ,因此 ,该系统具有较合理的物质循环结构。     

水电工程对农业生态系统服务功能价值评估——以汉江崔家营航电枢纽工程为例

利用遥感技术测算汉江崔家营航电枢纽工程淹没区各种农业植被的面积。以此为基础数据,采用市场价值、碳税法和替代工程等方法,对工程修建前的农业生态系统服务功能的价值进行评价。结果显示:淹没区内农业生态系统服务功能每年要产生农产品服务价值2242.38万元,大气组分调节价值556.31万元,减少土地损失的价值278.8万元,减少土壤肥力损失的价值3711.71万元,涵养水分的价值101.37万元。工程建成后,淹没区内的农业生态系统服务功能将消失,因此,工程的修建使农业生态系统服务功能的价值减少6890.57万元。     

海门市农村水环境污染现状与对策措施

农村水环境受到农业、生物、生活、工业等方面的污染,影响了农村水资源的综合利用和农民居住环境质量的改善。采取开发水产养殖、加快农村水利建设,推行生活垃圾卫生填埋、加大工业污染治理力度等措施,沟河环境得到标本兼治,农民群众收入增加,水环境质量得到提高。     

中国亚热带东部丘陵山区农业自然资源开发策略

我国亚热带东部丘陵山区农业生产条件优越,但由于农业生产主要局限在耕地上,沟谷农业限制着整个农业的发展,一些农村仍处于贫困状态。本文通过对农业生产条件的综合研究和对沟谷农业的进一步分析,提出了充分利用自然资源,使整个山区致富的根本出路是:摆脱沟谷农业的束缚,发展生态农业生产和商品经济,壮大农村实力,农业生产走上良性循环的道路。     

Eco-environment contribution of agroforestry to agriculture development in the plain area of China--Huai''an Prefecture, Jiangsu Province as the case study area

For improving the environmental quality and ensuring supply of wood and non-timber forest products, many forests have been planted in plain areas of China. Scientists have studied their benefits, almost all of the approaches were based on tixed-point data, and few was considered on the non-efficient factors and temporal scale effects. This paper studies the positive and negative benefits at a large temporal scale, and the effects of plain afforestation on stockbreeding and rural economy. The benefits of plain afforestation, correlation coefficiency of agroforestry and production factors are analyzed via stochastic frontier modeling in Huanghuaihai Plain Area of China; elastic coefficient of agroforestry, husbandry, farming, and total output of agricultural sector are calculated through adopting partial differential equation. Some conclusions can be drawn that, plain forests have an important effect on the development of plain agriculture. But shelterbelts and small-soale forests have different effect on the development of agricultural economy. Shelterbelts have negative effect on the industries, but small-soale forest has positive effect. On the whole, contribution of forest resource to value of animal husbandry and gross production value of agriculture is positive, and to the value of farming is negative.     

论农业资源利用的有效性

人类社会经历了农业、工业和生态三个革命，当前正进入生态化社会和建设新的生态文明。新的时代要求人们自觉用生态与经济协调的思想为指导，规范自己的经济思想和经济行为，引导农业走持续发展道路。为此，一个重要的问题是明确以农业资源利用的有效性（而不是最大）作为基准点，指导合理利用农业资源。其内涵包括：①积极利用；②节约利用；③充分利用。以此为基础，在生产实践中推进农业资源的广度利用、深度利用和适度利用。