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1.
四川省南充地区小麦套玉米-甘薯三熟中厢分带轮作用地200万亩左右。近年来西充、南部和南充等县采用麦-玉-薯的薯垄边种植早秋玉米,或在双行早玉米两边靠宽行各种一行早秋薯,收到了显著的增产效果。一般每亩可增收玉米100~150kg,或增收甘薯110~160kg。这种多熟组合模式能充分利用时间差,开发晚秋自然资源,提高复种指数和土地生产力;特别是提高粮食产量,增加养猪的精、粗饲料,为粮食上新台阶开劈了新途径。其方法为:1.早秋玉米:①选地:一般以靠水源方便、土层深厚的一台地或河坝地较好,以利抗御伏旱。②品种:据近年品比试验和大面积示范,早秋玉米的品种为中单2号和丹玉13号等中熟杂交良种。③播期:安全播期是早秋玉米能否避灾增产的关键;因此,扬花期应安排在伏旱尾至秋淋前,南充地区一般在8月20日至9月10  相似文献   

2.
抽样选择毗邻太湖的常州市武进区雪堰镇3个村,调查当地种植结构及变化,肥料、农药过量施用情况,以及农民对农业面源污染的认识。结果显示,肥料投入总量依次为:蔬菜〉水蜜桃〉葡萄〉稻麦轮作〉稻油轮作〉柑橘〉茶叶;稻-麦轮作、水蜜桃和柑橘3种主要种植模式都存在肥料过量施用,稻-麦轮作N投入过量,水稻和小麦过量的比例分别为40.00%和53.57%,水蜜桃和柑橘则是P2O5投入过量,比例分别为85.71%和25.00%。因此,太湖地区减量施肥的潜力较大。农药投入近年来有所下降,但绝对投入量仍较大,远高于10-15年前的使用量,也有较大的减量空间。当地农民对农业面源污染缺乏认识,急需宣传提高。  相似文献   

3.
本文通过稻油鱼菇多元农业生态模式的田间试验及数理统计分析,介绍了深沟小垄稻油鱼菇农业生态构型的田间合理布局,田间生态结构、食物链特征及增产效果,论述了这类生态田的高产稳产原理。  相似文献   

4.
通过推广配套“稻-鸭-油”模式应用技术,实行绿色生态农业生产,大量减少农药、化肥等化学品投入,农产品质量和农田生态环境都得到改善,取得了明显的三大效益。  相似文献   

5.
田间试验表明,深沟窄畦结构扩大了稻田生物的生境容量,畦麦沟鱼、稻鱼共生结构提高了稻田生产力,稻麦年产量稳定达到10.84~11.83t/ha,鱼产量3.11~4.20t/ha,在稻田产出中鱼占有最大产值优势度,系统能流结构表现出新特点,生态效率高。  相似文献   

6.
蘑菇在稻油鱼菇生态田中的合理布局及作用刘祖贵,赵先男为提高土地的利用率,增加农民的收入,我们从1991~1994年进行了“三高”农业种植模式之—──稻油鱼菇生态结构的研究。研究结果表明,蘑菇插入田间后对水稻、油菜均具有较大的增产作用。研究方法:研究工...  相似文献   

7.
本文提出了农业生产潜力指数评价的基本理论和方法,并利用这一评价方法对内江市主要家业作物的生产潜力的进行了评价分析。  相似文献   

8.
我国的农业正处在传统农业向现代化“生态农业”转化的阶段。目前已出现一批自然形成的生态农业典型:①稻-蔗(桑)-鱼-猪(禽)相结合的结构模式。②稻-鱼共生的生态农业模式。③以水产养殖业为主的生态农业模式。④农牧渔全面发展的生态模式。⑤旱地浪林草牧型生态农业。⑥城郊菜、奶、果、禽、鱼型生态系统。归纳为森林生态系统、农田生态系统以及水域生态系统,及这三个生态系统互相交错的各种类型的生态系统等。  相似文献   

9.
本文论证了湖北稻区的资源具有三大特点。因此,认定该区应细分为:东南部早三熟双季稻区,中部单、双季稻两热三熟并存区,西北部单季稻两熟区。笔者认为,本区近10年发展麦稻、油稻稻、油稻减少肥稻稻、肥稻其主流是好的;讨论了紫云英大量减步后如何解决有机肥源匮乏的问题。主张今后应积极开发冬种,积极提倡冬作起厢分带间套,既稳定大宗作物的发展,又增产经作、饲料、蔬菜、绿肥,以提高稻田的经济效益。  相似文献   

10.
本文研究了稻麦两熟养鱼高产的调控原理,提出了稻麦连作,畦麦沟鱼、稻鱼共生的稻田全年养鱼技术。①利用深沟窄畦扩容和稳容,改造生境容量;②采用畦麦沟鱼、稻鱼共生结构调节群落的种群密度和生态位宽度,延长养鱼时间;③按照生物种群的生态型对水层敏感性实施田间水位和流水增氧调控,提高养鱼产量;④提高稻麦两熟养鱼的生产率,合理投入,以生物质能为主源输入稳定系统结构。  相似文献   

11.
The agricultural and industrial development of small cities is the primary environmental management strategy employed to make full use of extra labor in the rural areas of China. The ecological and economic consequences of this development strategy will affect over 100 million people and change the organization of the Chinese landscape. In this study, we examined the agricultural development of Shunde, a small city in Guangdong Province, over the period 1978 until 2000. Our analysis of the ecological and economic dynamics of the agricultural system revealed the dominant role of labor in the intensification of agricultural production, even though the use of fuels, fertilizers and machines also increased during this time. The Shunde agricultural system was examined from both biophysical or donor-based and human utility or receiver-based perspectives, using emergy and economic methods, respectively. After 22 years of urbanization, the Shunde agricultural system was still able to fill 96% of the local demand for agricultural products using only 6% of its total yield compared to using 14% of the total yield in 1978. Aquaculture developed quickly during the study period as grain production decreased. In 2000, the production of fish, pork, and vegetables accounted for 92% of the total emergy output of the system; however, the emergy buying power of the money received in exchange was lower than the emergy contained in the products exported. The excess emergy exported is the basis for a high quality diet delivered to city dwellers at a relatively low price. In the 1980s, the productivity of both land and labor increased; but after 1992 the productivity of labor decreased, causing the efficiency of the whole agricultural system to decrease. We recommend that processing plants be established for the main agricultural products of Shunde to decrease the emergy loss in trading and to increase employment. The effect of including monetized ecosystem services in the balance between the emergy delivered to the markets in agricultural products and the emergy buying power of the money received was to decrease the emergy gained by the Shunde agricultural system.  相似文献   

12.
丁雪卿 《四川环境》2010,29(2):47-51
以《地表水环境质量标准》(GB3838-2002)为基础,选取溶解氧、高锰酸盐指数、CODC r等20项指标作为评价指标,采用内梅罗污染指数法的改进方法对内江市5处饮用水源地进行综合评价,并将评价结果与单因子评价法进行比较。结果表明,内江市5处饮用水源地水质状况较好;内梅罗污染指数法的评价结论比单因子评价法的评价结论更科学、合理和全面的反映综合水质状况。  相似文献   

13.
本文对内江市沱江流域经济-环境系统1995~2010年时段可持续发展进行了预测分析,指出了该区域实现可持续发展的可能途径和对策措施.  相似文献   

14.
四川省农业生产环境因素-化肥施用状况宏观分析   总被引:3,自引:1,他引:2  
本文首次提出“区域化肥施用负荷”、“化肥施用相对生产力”、“化肥施用相对适宜度”等概念及研究方法,用于四川省化肥施用状况宏观分析。四川全省化肥施用量F=228.86kg/hm^2,全省21个市州中自贡、攀枝花、德阳、绵阳、遂宁、眉山、雅安和巴中等8个市F〉250kg/hm^2,其中攀枝花市达到457kg/hm^2;全省5个农业区中,成都平原区F值最高,达285.63kg/hm^2。四川省化肥施用负荷H=4704kg/km^2,自贡、德阳、遂宁、内江等4市H值是全省H值4倍以上,自贡、遂宁2市甚至达5倍以上;成都平原区、盆地丘陵区H值分别是17491kg/km^2和16309kg/km^2,远远高于其他地区。全省化肥施用相对生产力R=20.26kg,攀枝花市R=12.11kg,是全省最低的;盆地丘陵区R=20.16kg,其余地区R值均高于全省的。全省近10年平均化肥施用相对适宜度T=3.19作为评价基准,攀枝花市T=5.22,是全省最高的,属化肥施用高度过量;各农业区中,盆地丘陵区T=3.47,盆周山地区T=3.28,属化肥施用轻度过量,其余地区基本适宜。  相似文献   

15.
赵中金  黄昀  周优良 《四川环境》2006,25(4):123-126
对重庆市农业环境质量安全现状进行了研究分析,提出了充分利用环境资源比较优势,进行农业生产布局和农业结构调整;加强城郊区农业生态环境保护和污染的治理;合理施用农药化肥,防止农产品农药残留和硝酸盐污染;加强全市农业环境与农产品质量安全监测体系建设,开展预警监测;加强三峡库区农业面源污染防治;进一步开展农业环境优先污染物的控制研究等防治对策。  相似文献   

16.
我国粮食生产的制约因素较多。为了达到我国粮食产量稳定增长的目的,我们必须针对我国农业资源的特点,趋利避害,充分发挥其优势,挖掘生产潜力;搞好宏观调控,调动各方面的积极性,发展粮食生产。这样,2000年实观我国粮食总产量达到 5亿t,人均占有粮食400kg 的目的是可能的。  相似文献   

17.
The right to eat and to an adequate standard of living for everyone motivates agricultural research assistance to developing countries with the primary objective of assuring sufficient food supply. This article focuses on aspects of food production and related agricultural research with specific examples from animal production. It discusses ethics of agricultural research in light of the utilitarian theory and compares livestock production in developing and developed countries. Major reasons for low outputs of animal production in developing countries are identified, and the potential for increasing the productivity of original, extensive production systems is evaluated. The article reviews the current status of biotechnology in developing countries and discusses several advanced animal technologies. The conclusions emphasize the need to involve local professionals in all phases of research and technology transfer in developing countries, avoidance of research that may worsen the situation of the recipients, sustainability of production systems, and the need for detailed assessment of potential impacts of technology on recipients.  相似文献   

18.
This paper uses data from the Central Highlands of Ethiopia to assess the productivity and production risk impacts of crop diversification. Using count index as a measure of crop biodiversity, results show that increasing crop biodiversity contributes positively to farm level productivity. In addition, the findings suggest that the level of production risk significantly responds to the level of diversity, with the effect highly conditional on the skewness. The major contribution of the paper is that, unlike previous similar studies that tended to focus on intra‐crop diversity, it incorporates the mutual interdependencies across crops within a farm by focusing on inter‐crop diversity. Hence the study adds to the growing empirical literature, particularly in Africa, that tests empirical relationships between productivity, risk and crop diversity. An important policy implication for a diversity rich country such as Ethiopia is that agro‐biodiversity can be used to improve agricultural productivity while promoting in situ conservation.  相似文献   

19.
The environmental Kuznets curve (EKC) hypothesis assumes the nonlinear relationship between production and its environmental effects, suggesting that the negative effect of production on the natural environment is reversed at higher levels of development. In contrast to the majority of the studies, this paper considers the possibility of non-linear effects of per capita output on agricultural land use (cropland), as one of the natural resource stocks, and additionally examines the influence of demographic and productivity variables on the agricultural land use. The study draws on panel data from 143 economies over the 1990–2019 period and employs a series of panel econometrics techniques (including panel unit root and cointegration tests, panel ordinary least squares, generalized method of moments, and panel quantile models). The results unequivocally indicate the inverted U-shaped relationship between the GDP per capita and cropland use, as per EKC hypothesis. The results are robust with respect to employing different techniques, the identified turning points correspond to low and low-middle-income levels, and the effects of agricultural productivity and population density on land use are respectively negative and positive.  相似文献   

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