元阳哈尼梯田农民种子系统和农业文化景观格局

Farmers′ Seed System and Agricultural Cultural Landscape Pattern in the Yuanyang Hani Terraced Fields

人类干扰导致的景观结构变化促使生物多样性保护途径从传统的、以物种为中心的自然保护途径向强调生态系统保护的景观优化管理途径转换,景观要素的形状、组成、变化和稳定性对景观中的物种及其功能有重要影响和作用。本文从景观尺度来研究梯田农业文化景观中的传统物种及传统农耕活动的利用与保护,分析梯田农民种子系统和梯田农业景观格局特征的关系,探讨元阳县哈尼梯田农业生物多样性保护的景观优化管理途径和种质资源创新管理途径,对梯田景观生态和绿色农业的可持续发展有一定现实意义。结果表明,(1)2007-2016年,哈尼梯田林地和水域面积趋于减少,而旱田和居民点趋于增加,水田呈先减后增再稳定态势,梯田景观细碎化程度总体呈升高趋势。(2)传统稻种30年来流失近一半,稻种多样性整体呈下降态势;近年来农户轮换种植传统品种有50个,仍有46%农户种植传统品种,农户通过种间流动、交换、轮换,从时间和空间上维持了稻种多样性和内部遗传异质多样性,多样性稻种的种植促使梯田景观得以稳定留存。(3)梯田林地(0.319)、旱田(0.153)与稻种丰富度呈正相关,水田(-0.367)、居民点(-0.15)与稻种丰富度呈负相关关系;回归分析表明:水田面积越多,传统稻种种植有减少趋势,而林地越多,种植的传统稻种越多;旱田面积显著影响稻种病虫害的发生,旱田越多,稻瘟病情越高,而居民点越多,病情指数越少;随海拔升高,传统稻种的种植呈上升趋势,而水田呈下降趋势;梯田水稻生态系统通过小斑块控制病虫害发生,维持稻种多样性。

Landscape structure changes caused by human disturbance prompt the transformation of biodiversity conservation approaches from traditional,species-oriented natural conservation approaches to landscape optimization management approaches that emphases ecosystem protection.The shape,composition,change and stability of landscape elements had an important impact on species and their functions in the landscape.This paper studies the utilization and protection of traditional species and traditional farming activities in terrace agricultural cultural landscape on landscape scale,and analysed the relationship between terrace farmers'seed system and terrace agricultural landscape pattern characteristics,and also explored the ways of landscape optimization management and innovative management of germplasm resources for the protection of agricultural biodiversity in Hani terrace,which was of practical significance for the sustainable development of terrace landscape ecology and green agriculture.The results indicated that:(1)Terrace forest land and waters tended to decrease in 2007-2016,while dry land and residential areas tended to increase,paddy fields tended to decrease first,then increase and finally stabilize,and the degree of terrace landscape fragmentation overall tended to increase.(2)Nearly half of the traditional rice seed was lost in past 30 years,the overall diversity of rice varieties showed a downward trend in recent years;there were still 50 traditional species that farmers grew in rotation,and of all farmers,there were still 46%of them tending to plant traditional varieties,from time and space to maintain the diversity of rice varieties and genetic heterogeneity diversity through varieties flowing,exchanging,and planting rotation,the cultivation of rice seeds promoted the stability of terrace landscape.(3)Terraced forest land(0.319),dry land(0.153)were positively correlated with rice species richness,and paddy field(-0.367)and residential area(-0.15)were negatively correlated with rice species richness.(4)Regression analysis showed that the more paddy fields,the lower tendency of traditional rice planting;and the more forest land,the more traditional rice planted.Dry-land area significantly affected the occurrence of rice diseases and pests,which showed the more dry-land,the higher rice blast,and the more residential areas,the less disease index.With the increase of altitude,the planting of traditional rice seeds showed an upward trend,while paddy fields showed a downward trend.The rice ecosystem in the terrace can control pests and diseases through small patches and maintain the diversity of rice varieties.