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11.
平江县实施农业综合开发已有12个年头了。随着形势的发展.国家对农业综合开发的在不同时期其开发的任务也有所不同。农业综合开发的现阶段的建设重点和内容由过去以改造中低产田和开垦农荒地相结合,转到以改造中低产田为主和保护生态环境上来;由过去追求增加主要农产品产量为主,转到发展优质、高产、高效农业上来。如何创新思路,提高农业综合开发水平,需要在工作实践中不断探索。  相似文献   
12.
引进温室带给中国设施园艺现代化的思考   总被引:14,自引:0,他引:14  
中国引进现代化温室面积已逾200hm^2,对中国温室业的发展起到了积极的推动和示范作用。本在回顾和总结引进温室的基础上,通过实例分析对中国未来现代化温室的发展和建设提出了一些借鉴经验,尤其在温室节能、温室管理等方面就在地制宜发展中国设施园艺工程提出了一些具体的看法。  相似文献   
13.
该文阐述了切实加强专项管理工作领导的重要性,强调要落实责任,加快专项预算执行进度,提出从业人员要加强学习与培训,努力提高业务素质,切实做好2007年、2008年修购项目验收工作及2010年修购项目实施的前期准备工作。  相似文献   
14.
Wildlife tourism alters the environmental conditions in which the focal animal lives, and it is therefore necessary to assess the ability of the animal to adjust to and persist in these novel conditions if the industry is to be sustainable. Here, we report on the physiological responses of southern stingrays (Dasyatis americana) which are the focus of intense marine provisioning-tourism in the Cayman Islands. Using stingrays from non-tourist sites about Grand Cayman as a basis for comparison, we show in this natural experiment that tourist-exposed stingrays exhibit hematological changes indicative of physiological costs of wildlife tourism. The novel conditions with which the stingrays must interact include non-natural food, higher injury rates (from boats, conspecifics and predators), and higher parasite loads (from crowding conditions). As a result of this year-round environment, stingrays display sub-optimal health: lower hematocrit, total serum protein concentrations, and oxidative stress (i.e., lower total antioxidant capacity combined with higher total oxidative status). Moreover, they show evidence of attenuation of the defense system: for tourist stingrays only, animals possessing both injuries and high parasite loads also exhibit lowest leukocrit, serum proteins and antioxidant potential, as well as differing proportions of differential leukocytes indicative of suppression (lymphocytes and heterophils) and down-regulation (eosinophils), thus suggesting that the physiological changes of tourist stingrays are in partial response to these stressors. While survival- and reproduction- quantification was not possible in this long-lived marine species, the physiological measures -situated within ecological context, indicate that the long-term health and survival of tourist stingrays have a significant probability of being affected. Consequently, management of the tourism attraction is essential. The indicators chosen in this study reflect general health indices and defense capabilities used across taxa, and represent a tradeoff between ease of collection/analysis and interpretation so that managers can continue the research for monitoring purposes.  相似文献   
15.
作者介绍了《捕捞许可证数据库网络系统》,这是借鉴国内外管理经验提出的,最终实现大连市渔政部门与所属各县区形成一个渔政管理的计算机通讯网络,为进入“全国渔业管理信息系统工程”做基础准备,其目的利用现有渔政设施逐步提高宏观调控能力,循序渐进达到科学化、规范化的管理效果,使渔业生产获取最佳的经济效益和社会效益。  相似文献   
16.
The management of burnt wood after a fire may affect seed predation by vertebrates due to the change produced in habitat structure. We analyze the effect of burnt wood management on post-dispersal seed predation in the Holm oak. Three plots were established in a burnt forest, with three treatments per plot: (1) non-intervention (NI, all trees left standing), (2) “partial cut plus lopping” (PCL, felling 90% of trees, cutting their main branches, leaving all the biomass in situ), and (3) “salvage logging” (SL, felling the logs for their removal and masticating the woody debris). Acorns were buried to mimic dispersal by jays or rodents two and three years after fire, with two trials per year (7200 monitored acorns), and the predation rate was evaluated until the time of seedling emergence. The spatial patterns of acorn predation were assessed by computing a transformed-Ripley's K function and Moran's I correlograms. There was a large spatial and temporal variability in acorn predation, with differences among trials, plots, and replicates within treatments and plots. Overall, PCL showed the lowest predation values (83.0% versus 87.4 in NI and 88.0 in SL). Predator species (mice versus wild boar) also differed among treatments, wild boar having a negligible effect in PCL, presumably due to the physical barrier of felled logs and branches. The results support that: (1) salvage logging offers no advantage against predators and (2) that post-fire burnt wood management alters the guild of acorn predators and may reshape the pattern of seedling establishment.  相似文献   
17.
In this paper we document how changes in forest structure mediated by natural (hurricane) and human (logging) disturbances affect natural regeneration of Swietenia macrophylla via its effects on seed predation, germination, and early recruitment. Work was carried out in two ejidos within the Mayan zone of Quintana Roo, differing with regard to their exposure to the effect of the hurricane Dean 2008 (Naranjal Poniente; high hurricane impact) and Señor (with no evidence of hurricane effects). We experimentally set S. macrophylla seeds in both hurricane conditions and contrasting logging effects, in three treatments: (1) open access, (2) rodent and insect access and (3) rodent and insect exclusion. We measured three dependent variables: (i) number of seeds predated, (ii) number of seeds germinated and (iii) number of seedlings established. We found that the three variables measured were differentially affected by logging and hurricane Dean. Seed predation was higher in areas with hurricane effects; germination showed no differences, but early recruitment was differentially affected by the two conditions, via an increasing of herbivory and sun exposition. Both types of disturbances studied occurred periodically in Yucatan Peninsula and elsewhere in tropics, so it is necessary to implement specific actions in order to face changes in mahogany natural regeneration stocks, and supporting the future management of tropical forests.  相似文献   
18.
Unbalanced and excessive use of N-fertilizers causes environmental pollution, lodging of plants and increased pest pressure, in addition to increased cost to farmers from excessively applied fertilizers and pesticides. N application at the right time and in right amount is critical for healthy plant and environment. Rice leaf color intensity is directly related to leaf chlorophyll content and leaf nitrogen status. The concept for the use of leaf color as an indicator to apply N in rice was crystallized during 1990s. The International Rice Research Institute and the Philippine Rice Research Institute developed a leaf color chart (LCC) that helps guide farmers for real-time nitrogen management in rice farming. The technology is inexpensive, and easily affordable by most resource poor rice farmers. In 2003 we initiated a farmer-participatory research to validate real-time N management in rice by the use of LCC in West Bengal state of India. After 3 years of validation research, a survey was conducted to assess the adoption and impact of LCC. The survey was conducted in both intervention and adjacent control villages and data were collected from 20% farm households selected randomly. In this paper, we report findings of the study on the determinants of adoption of LCC, and its effect on fertilizer and pesticides use.  相似文献   
19.
黑河流域草地资源保护与建设   总被引:1,自引:0,他引:1  
黑河流域除绿洲地区外有160万hm2的草地,进行草地分户、围栏封育、人工改良草地;牧户按地定畜、优化牧场、推广良种、改良畜群;按草定牧、实行休牧和轮牧;革新观念、子羔出栏、加速出栏周期、保障牧民增收等措施可保护草地资源,加速草地建设,繁荣牧区经济.  相似文献   
20.
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