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1.
相对于种质资源的异位保护,作物地方品种的农家保护和利用作为植物种质资源保护方法被提出,但是,关于这种方法的有效性却知之甚少。文章采用问卷式和农村参与式调查评价方法(PRA),通过对云南省15个特有少数民族分布的11个州(市)、36个县、124乡(镇)、237个行政村中的306个村寨(村小组),针对当前农家保护的稻、麦(包括小麦、大麦、燕麦和黑麦)和玉米地方品种多样性进行实地调查分析,结果发现已有44.8%的村寨稻地方品种丢失,77.5%的村寨麦地方品种丢失,37.3%的村寨玉米地方品种丢失。共调查采集到农家保护的地方品种901个,其中稻、麦和玉米分别为371、119和411个。每个村寨均有农家保护的地方品种(平均为2.9个),平均每100户农户、1 000人和100 Ha耕地面积分别有3.3个、8.0个和5.2个地方品种。其中,尤以西盟县勐梭镇里拉村委会老缅小组有18个地方品种(包括10个稻和8个玉米),元阳县新街镇土戈寨村委会箐口村有14个稻地方品种最为突出,实属少见。同时,各民族农家保护的地方品种多样性存在显著差异,变幅为16~120个,其中,稻在各民族中的分布变幅最大,为1~72个,主要分布于滇南、滇西南热带、亚热带民族地区;麦变幅次之,为0~47个,主要分布于滇西、滇西北高海拔、温凉民族地区,且在傣族、基诺族和阿昌族等3个民族中已丢失;玉米变幅最小,为4~40个,最均匀。总之,各民族农家保护地方品种的主要驱动力是满足该民族传统文化习俗的生活需求,以及由于缺乏适宜当地特殊生境的新品种以满足生产需求。因此,云南特有少数民族地区是开展农家保护研究的理想基地,建议在该区域选择一定村寨建立地方品种农家保护示范区,同时加强对当前农家保护的地方品种的高效利用研究。  相似文献   

2.
农业活动对生物多样性的影响   总被引:43,自引:3,他引:40  
农业生产活动如土地的农业利用、耕作、作物间套种植方式、放牧、农药化肥的使用以及农业动植物遗传改良(包括外来种引入)等是农业生产力提高的重要途径,同时也是影响生物多样性的重要因素之一。土地的不合理开发利用易导致生境破碎、生物多样性下降;大规模的机械耕作导致土壤动植物区系的变化,甚至某些物种的消失;农药(除草剂、杀虫剂等)的高度使用使非靶标动植物受到伤害;品种改良、外来种的引入以及远缘外源遗传物质的利用(如远缘杂交和DNA导入分子育种)在丰富了遗传多样性的同时导致农作物类型和品种的简单化、一些古老的地方种和农家种等传统资源丢失等;而一些合理的农业措施(间套作、实行有机农场等)将有利于生物多样性的保持。农业活动注重的是农业生产力的提高而往往忽视其对农业系统中野生动植物(包括有害和无害)的影响以及野生动植物在维持系统稳定和平衡的作用。本文论述农业活动对生物多样性的影响以及生物多样性保护对提高农业生产力的作用,启示人们采取合理的农业活动方式,合理管理有害生物,减少农业活动对生物多样性的负面影响。  相似文献   

3.
中国利用生物多样性控制水稻病虫草害技术   总被引:3,自引:1,他引:2  
病、虫、草害是影响水稻生产的主要因素,利用生物多样性控制水稻病虫草害符合农业可持续发展的要求.近年来,中国利用生物多样性防控水稻病虫草害技术的研究大量涌现.本文对中国近年来在利用外源基因培育抗病虫草水稻品种,利用水稻种质资源、稻鸭共作、有机耕作、生物制剂技术防治水稻病虫草害等方面取得的成果和进展进行了综述,并对未来有待进一步研究的方向进行了展望.利用丰富的水稻种质资源进行抗病虫草育种和筛选抗病虫草品种是利用水稻品种遗传多样性研究的重要方向;进一步开展利用生态系统多样性控制病虫草害的方法,研究不同生物多样性方法之间的匹配或者拈抗关系,将有利于可持续水稻生产技术体系的发展.  相似文献   

4.
农业生物多样性保护的景观规划途径   总被引:9,自引:0,他引:9  
农业生物多样性保护不仅关系到农业可持续发展,也是物种多样性保护的重要组成部分.近年来,生物多样性保护更加强调通过景观规划途径来实现.本文在回顾国内外关于景观结构对生物多样性影响一般性结论和研究结果的基础上,从景观、地块间、地块内3个尺度分别探讨了农业生物多样性保护的景观规划途径,并建议可以通过采取如下途径有效地保护农业生物多样性:1)在景观尺度上,维持较高比例的自然、半自然生境,注意农用地和种植作物的多样化,注重树篱等廊道生境的保护和建设;2)在地块间尺度上,构建农田边缘地带;3)在地块内尺度上,合理地规划作物种植密度、作物空间分布及采取间套作、轮作等方式.此外,大尺度景观规划途径的实施还需要诸如自然保护计划、土地利用规划及生态补偿等相关政策措施的配套与支持.  相似文献   

5.
陶战 《生物多样性》1993,1(1):46-47
中国农业部门利用的国土面积达50%,农业生态系统是由古代生物多样性丰富的自然生态系统开发出来的,在农业生态系统中仍残存生物多样性富集的岛状野生生境和大量珍稀、濒危物种。农业上栽培和养殖利用1200多个动植物品种也是宝贵的种质资源,农业部门在保护生物多样性行动中责任重大。生物多样性是农业发展的潜在资源,开发不当会带来对农业再发展的危害。农业部门已开始了生物多样性保护行动,但存在许多需要改善与加强的环节,如国家首先要明确落实农业部门在保护生物多样性中的责任,保护农业生物多样性要列入国家和部门的发展计划,完善法规、政策、加强宣传教育,加强国内外合作交流等。  相似文献   

6.
生物多样性控制作物病害研究进展   总被引:5,自引:0,他引:5  
杨静  施竹凤  高东  刘林  朱有勇  李成云 《遗传》2012,(11):1390-1398
自然资源的合理利用和生态环境保护是人类实现可持续发展的基础,生物多样性的研究和保护已成为世界各国普遍关注的重大问题。农作物病害是农业生产上重要的生物灾害,是制约农业可持续发展的主要因素之一,抗病品种大面积单一化种植导致了农业生物多样性水平严重降低,因而农业生物多样性的过度丧失已成为可持续农业所面临的主要难题。利用生物多样性持续控制作物病害能减轻作物病害发生和作物产量损失,达到保护作物多样性,减少农药过量施用给农业生态环境造成破坏的最终目的,而揭示生物多样性控制作物病害的机制能有效地指导生产上对不同作物进行合理布局和轮换,建立作物不同组合的优化搭配和种植模式。文章从分子、生理和生态水平研究农业生物多样性控制作物病害的机制、以及影响作物多样性控制病害的因素、覆盖作物等几方面对生物多样性控制作物病害的研究进展进行概述,同时对今后生物多样性控制作物病害机制还需加强的研究部分进行了展望。  相似文献   

7.
何思源  闵庆文 《生态学报》2022,42(15):6041-6053
以国内外文献、报告、规划为原始材料,以"保护兼容"一词为核心,结合其使用语境,系统阐述在自然保护话语由"堡垒式"转向"社区保护"时,随着自然保护地功能与管理发生变化,人类活动的保护兼容性如何被重新发现并在自然保护实践中助力生物多样性保护。研究发现,"保护兼容"理念充分体现在景观尺度的土地利用连续体上;在生产性景观视角下乡村土地利用和传统农业系统进入自然保护领域;"保护兼容"理念以土地利用为基础下沉到乡村社区的资源管理、生计发展等多类型活动,以各种保护倡议和项目实现,并在发展中国家和发达国家呈现出不同特征。"保护兼容"理念既进行尺度扩展,探索区域内、跨行政区域乃至国家间多利益相关方参与、多类型土地利用贡献于自然保护扩展,也进行尺度下沉,倡导基于本土价值实现全球价值的保护理念。研究提出,全球在生物多样性保护中要进一步重视生产性景观和农业生物多样性保护,而发展中国家面对全球生物多样性保护紧迫目标时,需要坚持社区主体性和在保护实践中的主动性。  相似文献   

8.
《生物多样性公约》第十五次缔约方大会(COP15)计划于2021年在云南昆明召开, 大会将评估《2011-2020年生物多样性战略计划》执行情况及实施进展。如能达成协议, 将出台“2020年后全球生物多样性框架”, 作为指导2020年之后全球生物多样性保护的最新纲领性文件。这是生物多样性保护国际进程的一个里程碑, 也是展现中国以及云南多年来生物多样性保护成效的重要契机。作为中国生物多样性最为丰富的省份和具有全球意义的生物多样性关键地区之一, 云南在生物多样性保护方面投入巨大努力, 在全国较早发布省级《生物多样性保护战略与行动计划(2012-2030年)》、开创地方立法先河、率先试点建设国家公园、较早开展县域生物多样性本底调查与评估研究工作、建立了首个国家级野生生物种质资源库等, 在就地保护、迁地保护、重大生态工程等众多领域都取得显著成效。本文在梳理云南生物多样性保护进展与成就的基础上, 对保护成效进行了评估, 并有针对性地探讨了云南生物多样性保护未来发展方向及重大意义, 加强全省农业生物多样性的保护与可持续利用、发挥跨境生物多样性保护及减贫示范作用、协调发展生物多样性保护与少数民族传统知识保护等方面是云南省生物多样性保护今后发展的重要方向, 同时本文也为进一步促进云南生物多样性保护与管理提供了基础资料, 并为COP15提供地方履约实例。  相似文献   

9.
转基因抗虫水稻对生物多样性的影响   总被引:1,自引:0,他引:1  
Zhang L  Zhu Z 《遗传》2011,33(5):414-421
水稻是我国最重要的粮食作物,然而虫害造成的产量损失每年高达一千万吨以上。研究表明,转基因抗虫水稻对二化螟、三化螟和稻纵卷叶螟等水稻主要鳞翅目害虫具有高抗性,可以大幅度减少化学杀虫剂的使用。在不使用农药的情况下,在抗虫转基因水稻田中的害虫密度大幅度减少的同时,可以显著地增加中性昆虫及捕食性天敌数量和种类,显示出稻田生态系统和生物多样性的向良性发展的趋势。转基因水稻花粉向非转基因水稻品种的基因飘流实验表明,随着栽种距离的增大而显著减小,到间隔6.2 m时基因飘流频率已低于0.01%。转基因抗虫水稻的应用,对于保障我国粮食安全,保持农业可持续发展,保护生物多样性和生态环境尤其是在大幅度减少农药使用量方面具有重要意义。文章综述了转基因抗虫水稻研制进展及其对生物多样性的影响,并对农作物害虫防治的未来研究方向和发展趋势进行展望,以期为转基因抗虫水稻更好的应用提供借鉴。  相似文献   

10.
农业活动及转基因作物对农田生物多样性的影响   总被引:2,自引:2,他引:0  
农田生物多样性是生态系统生物多样性的重要组成部分,但较少受到关注.近50年来,由于农业活动引起的环境污染、生境破碎和单一化种植等严重威胁着农田生物多样性.为了了解各因素对农田生物多样性的影响程度,优化农田管理措施,以提高农作物产量并降低环境影响,本文综述了种植方式、地膜覆盖、农药和化肥使用等农业活动及转基因作物对我国农田生物多样性的影响.农药和化肥的过度使用对农田生物多样性的影响最大;而转基因作物对农田生物多样性的影响受诸多因素影响,如携带的转基因性状等.需要加强转基因作物生态环境影响评价研究,特别是对农田生物多样性的潜在影响.农业生产活动应当与农田生物多样性保护密切结合,不仅有利于提高农作物产量,同时也可减少对环境的负面影响.  相似文献   

11.
Conservation of crop genetic resources is now considered an important component of sustainable agricultural development. If conservation of genetic resources for agriculture is to be successful, a more complete understanding of the dynamics affecting traditional (landrace) crop populations is needed. We conducted a study of maize-based agriculture in the Central Highlands of Mexico in communities at 2400, 1700, 1400, and 1200 masl to assess the status of traditional varieties in an area characterized by thorough integration into the national economy. Our research contradicts the view that modern varieties persist because of marginal conditions, deficient infrastructure, weaker markets, or traditional attitudes. One or two landraces dominated highland maize populations and farmers appeared to be more conservative in terms of their emphasis on traditional maize varieties than at lower elevations. The dominance of traditional varieties in the highlands is well known but poorly explained, and the coexistence of traditional and modern varieties in the mid-elevations was unexpected. Our highland study area has good roads, is near Mexico City, and is less than 50 km away from four major crop research institutes that have done maize breeding since 1950’s. We suggest that in situ conservation of maize genetic resources in the highlands is sustained because the landraces there have good agronomic performance and are highly valued by farmers for their end-use qualities. At the mid-elevations, competition between local and modern maize was sharpest, and farmers have found that both landraces and improved varieties suit their needs, hence enhancing genetic diversity. Interventions and incentives would appropriately be carried out here to assure in situ conservation of locally adapted landraces of maize.  相似文献   

12.
广西灵川县种植业的可持续发展   总被引:1,自引:0,他引:1  
广西是我国南方农业大省(区),明确其农业发展的制约因素,提出具体的解决措施,实现农业可持续发展,对解决农业、农村和农民问题,促进经济持续、快速、健康发展,实现社会主义现代化建设战略目标具有重要的理论和现实意义。主要采用了参与性农户评估方法(PRA),通过随机入户方式,与农户面对面交流,并结合调查问卷,对广西桂林市灵川县11个乡镇的农户进行了调查访问,为方便研究和数据处理,在数据分析过程中将该县11个乡镇分为3个片区:东部片区、中部片区、北部片区,对比3组农户的文化素质、种植制度、冬季农业现状、农业需求和农田水利设施等方面问题,探讨广西农业可持续发展的制约因素,并提出相应的对策,以期为广西农业可持续发展提供理论依据。调查结果表明,虽然目前灵川县农业取得众多发展成就,但仍存在以下几个方面的问题,严重影响了该县种植业可持续发展的进程。一是种植制度结构单一,二是冬季农业发展薄弱,三是种植技术贫乏,四是基础设施建设不完善等,因此,为促进灵川县种植业可持续发展,亟需采取以下对策和措施:调整作物种植结构,建立合理的种植制度;大力发展冬季农业;满足农民最迫切的农业需求;加强农业基础设施建设等。  相似文献   

13.
Because of the lack of varieties for organic agriculture, associations of organic farmers in several European countries have begun cultivating landraces and historic varieties, effectively practicing in situ conservation of agricultural biodiversity. To promote agrobiodiversity conservation, a special list for "conservation varieties" was implemented in 2008 by the EU because for any exchange and marketing of seeds in the EU, a variety must be registered in an official catalog. Our study aimed at improving knowledge on the phenotypic diversity and evolution of such varieties when cultivated on organic farms in Europe, in order to better define their specific characteristics and the implications for the registration process. We assessed multi-trait phenotypic evolution in eight European landraces and historic varieties of bread wheat and in two pureline variety checks, each grown by eight organic farmers over 2?years and then evaluated in a common garden experiment at an organic research farm. Measurements on each farmer's version of each variety included several standard evaluation criteria for assessing distinctness, uniformity and stability for variety registration. Significant phenotypic differentiation was found among farmers' versions of each variety. Some varieties showed considerable variation among versions while others showed fewer phenotypic changes, even in comparison to the two checks. Although farmers' variety would not satisfy uniformity or stability criteria as defined in the catalog evaluation requirements, each variety remained distinct when assessed using multivariate analysis. The amount of differentiation may be related to the initial genetic diversity within landraces and historic varieties.  相似文献   

14.
The Kingdom of Nepal extends 800 km east to west along the southern slopes of the Himalayas. Because of its biogeographical position, Nepal contains biological elements of both the Indo-Malayan and Palaearctic realms. Beside the trees in forest ecosystems, a large number of tree species are maintained on farms as part of subsistence farming systems. The role of these trees in ensuring the sustainability of agricultural production and the importance of traditional farming systems for the conservation of crop diversity have been well documented. However, the status of farm trees and their role in biodiversity conservation are poorly documented. This paper presents a case study of two villages in the western middle hills of Nepal. It highlights the role of traditional agroforestry practices for the conservation of tree diversity and argues that farms can be considered biodiversity reservoirs. Farm trees help to reduce pressure on community and government forests and create a favorable environment for many plant and animal species. Farm trees also provide social functions in that households with many farm trees no longer exercise their communal rights to extract grass products from community forests, which in turn benefits poor and disadvantaged households. The paper discusses possibilities to improve the role of farm trees in biodiversity conservation. It argues for the development of mechanisms such as tax exemptions and conservation credits that provide benefits to rural communities as compensation for their local and global environmental services including biodiversity conservation.  相似文献   

15.
Dynamic Management of Maize Landraces in Central Mexico   总被引:1,自引:0,他引:1  
Conservationists of crop genetic resources have feared that in situ conservation was not viable for agriculture precisely because of changes resulting from introduction of new varieties of existing crops, new crops, and new farm practices. In addition, conservation within farming systems necessarily implies a constantly changing crop population resulting from the processes of crop evolution. Even though in situ conservation of crop genetic resources is now generally understood to be dynamic, there are few examples of how evolution takes place in farmers fields. This study describes several changes in maize landraces in four communities along an altitude transect in Central Mexico (1200 to 2400 masl). While true modern varieties have not been widely adopted in the study region, farmer management results in numerous changes in maize landrace populations. Five types of dynamic management were observed: (1) purposeful hybridization between traditional and modern maize types, (2) possible creation of a new maize landrace by directional selection of the progeny of hybridization between two traditional landraces, (3) displacement of a local landrace by the introduction of a modern variety and a non-local landrace, (4) maintenance of stable populations of a locally dominant landrace, and (5) market-driven selection for a minor variety. We concur that in situ conservation of crops must be conceived as an open process where the objective is not to maintain historic varieties or static genetic conditions. Rather, in situ conservation of crops is totally in the hands of the farmer, although interventions may be designed to influence farmers’ management of agrobiodiversity.  相似文献   

16.
Nitrogen fixation in rice systems: state of knowledge and future prospects   总被引:9,自引:1,他引:8  
Ladha  J. K.  Reddy  P. M. 《Plant and Soil》2003,252(1):151-167
Rice is the most important cereal crop. In the next three decades, the world will need to produce about 60% more rice than today's global production to feed the extra billion people. Nitrogen is the major nutrient limiting rice production. Development of fertilizer-responsive varieties in the Green Revolution, coupled with the realization by farmers of the importance of nitrogen, has led to high rates of N fertilizer use on rice. Increased future demand for rice will entail increased application of fertilizer N. Awareness is growing, however, that such an increase in agricultural production needs to be achieved without endangering the environment. To achieve food security through sustainable agriculture, the requirement for fixed nitrogen must increasingly met by biological nitrogen fixation (BNF) rather than by using nitrogen fixed industrially. It is thus imperative to improve existing BNF systems and develop N2-fixing non-leguminous crops such as rice. Here we review the potentials and constraints of conventional BNF systems in rice agriculture, as well as the prospects of achieving in planta nitrogen fixation in rice.  相似文献   

17.
Worldwide, human appropriation of ecosystems is disrupting plant–pollinator communities and pollination function through habitat conversion and landscape homogenisation. Conversion to agriculture is destroying and degrading semi‐natural ecosystems while conventional land‐use intensification (e.g. industrial management of large‐scale monocultures with high chemical inputs) homogenises landscape structure and quality. Together, these anthropogenic processes reduce the connectivity of populations and erode floral and nesting resources to undermine pollinator abundance and diversity, and ultimately pollination services. Ecological intensification of agriculture represents a strategic alternative to ameliorate these drivers of pollinator decline while supporting sustainable food production, by promoting biodiversity beneficial to agricultural production through management practices such as intercropping, crop rotations, farm‐level diversification and reduced agrochemical use. We critically evaluate its potential to address and reverse the land use and management trends currently degrading pollinator communities and potentially causing widespread pollination deficits. We find that many of the practices that constitute ecological intensification can contribute to mitigating the drivers of pollinator decline. Our findings support ecological intensification as a solution to pollinator declines, and we discuss ways to promote it in agricultural policy and practice.  相似文献   

18.
In South Africa, restoration and sustainable management of historically overgrazed and degraded rangelands are promoted to increase biodiversity and ecosystem service provision. This study evaluates different land management scenarios in terms of ecosystem services in a South African rangeland, the Baviaanskloof catchment. As measured data were limited, we used simple models to quantify and map the effect of the different combination of agricultural, nature conservation and restoration practices on multiple ecosystem services. The land management scenarios were evaluated against management targets set for individual ecosystem services. Results highlight how the provision of ecosystem services is related to land management as unmanaged, pristine ecosystems provide a different mix of ecosystem services than ecosystems recently restored or managed as grazing lands. Results also indicate that historically overgrazed lands provide no forage, may retain 40% less sediment and have 38% lower biodiversity, while providing 60% more fuel wood and supplying two and half times more water (i.e. retaining less water), than pristine or restored lands. We conclude that a combination of light grazing, low input agriculture, nature conservation and restoration is the best for the sufficient provision of multiple ecosystem services. Applying such mixed management would improve biodiversity, ecotourism and maintain forage production and regulating services on farmers’ land. This management option also fits into and further optimizes local decision-makers’ vision regarding the future management of the area.  相似文献   

19.
It has been suggested that biodiversity in agroecosystems depends on both landscape heterogeneity and farm management, but at the same time, studies of biodiversity in relation to both landscape variables and farm management are rare. We investigated the species richness of plants, butterflies, carabids, rove beetles and the diversity of spiders in cereal fields, leys (grass and clover crop) and semi-natural pastures at 16 farms in Central East Sweden. The farms were divided into eight pairs of one conventional and one organic farm to enable us to separate the effects of landscape and farm management on biodiversity. The pairing was based on land use, location, and landscape features. Species richness of different taxonomic groups was generally not correlated. There were no differences in species richness between the farming systems, except for carabids that had higher numbers of species on conventional farms. The species richness generally increased with landscape heterogeneity on a farm scale. Habitat type had a major effect on the species richness for most groups, with most species found in pastures and leys. The correlations between species richness and landscape variables on a farm scale, and not on a scale of multiple farms, identify farmers as the important decision-maker in conservation issues for these taxonomic groups. We discuss the role of species richness of pests' natural enemies for biological control and conservation strategies of the more common species in the agricultural landscape.  相似文献   

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