摘要
在河北滨海盐碱荒地和盐碱低产田开展暗管改碱技术面临淡水资源严重短缺、灌溉条件差的问题,降水资源的利用对于该区域暗管改碱技术实施效果的影响很大。本文以河北省黄骅市为研究区域,对河北滨海盐碱区的降水特征及其对暗管改碱技术的影响进行分析。结果表明:当土壤含盐量<0.3%时,年内次降水量可完全满足土壤初次淋洗脱盐过程需要;当土壤盐分含量>0.3%但<0.5%时,在较容易淋洗的土壤上,暗管埋深合适时,脱盐需要的次降水量仍可基本满足;但当土壤含盐量达到0.5%左右时,仅靠自然降水不能保证土壤脱盐需要。暗管埋设条件下,雨季(6～9月)降水量对大面积的轻度盐碱地淋洗脱盐效果非常显著;但重度盐碱地却不能达到理想脱盐效果。从年降水量的变化情况看,研究区域降水量逐年降低的趋势比较明显,干旱年份多于洪涝年份,且旱情较为严重。因此未来推广实施暗管改碱工程时有必要考虑亏缺灌溉对自然降水淋盐的补充效果。
Shortage of fresh water and bad irrigation facilities limited reclamation of saline soil by using subsurface pipe drainage system in coastal regions of Hebei Province with saline-alkali wastelands and low-yield farmlands.This made the utilization of rain-fall a significant production practice in the region.Using Huanghua City as a case,this paper analyzed the rainfall features and effects of rainfall on the subsurface pipe drainage for saline soil reclamation in the coastal saline regions of Hebei Province.The study showed that at soil salt content below 0.3%,precipitation induced soil leaching and absolute desalinization.At soil salt content above 0.3% and below 0.5%,precipitation only induced soil leaching and desalinization when pipes were buried at proper depths and soils readily leachable.At soil salt contents above 0.5%,soil leaching and desalinization never occurred under whatever precipitation level.Under the current pipe conditions,precipitation in rain season of June through September induced significant leaching of slight saline-alkali soils.In severe saline-alkali soil regions,precipitation in the rainy season was not sufficient to leach and desalinize the soils.Based on rainfall analysis,there was a decreasing trend in annual precipitation.The frequency of drought also increased against that of flood.Application of long-term subsurface pipe drainage for saline soil reclamation should consider deficit irrigation to sup-plement rainfall and induce leaching in saline-alkali soils.
出处
《中国生态农业学报》
CAS
CSCD
北大核心
2011年第2期409-414,共6页
Chinese Journal of Eco-Agriculture
基金
国家科技支撑计划项目(2009BAC55B04)资助
关键词
滨海盐碱区
河北省
暗管改碱
降雨
淋洗
脱盐
有效性评价
Coastal saline region
Hebei Province
Subsurface pipe drainage for saline soil reclaim
Rainfall
Leach
Desa-linization
Effectiveness evaluation
