Taking its development in Baoding City as an example, we introduced service fields of rural cooperative economic organized united association. It mainly includes setting up service platform and providing scientific an...Taking its development in Baoding City as an example, we introduced service fields of rural cooperative economic organized united association. It mainly includes setting up service platform and providing scientific and technological services; organizing economic and trade negotiation and exchange, and promoting farmer-supermarket partnership; providing financial services and solving fund-raising problems. In line with these fields, we analyzed existing problems: (i) regional development is unbalanced and organization lacks internal connection; (ii) the development in some counties (cities) is to be improved, and the promotion effect is not significant; (iii) there is shortage of talent and the innovation strength is not enough; and (iv) it lacks system and management lacks restriction mechanism. Finally, we put forward countermeasures and recommendations: strengthen propaganda and cultivate farmers' cooperative awareness; incorporate rural cooperative economic organized united association into formal system arrangement, and absorb professional talents; innovate upon organization system of rural cooperative economic organized united association and improve service methods; improve internal operating mechanism and innovate upon working contents of rural cooperative economic organized united association at new development background.展开更多
【目的】随着人类活动引起大气活性氮排放的增加,大气氮沉降亦迅速增加,进而影响各区域生态系统。明确河北平原城市近郊农田大气氮沉降的动态变化,可以为农田氮素资源综合管理提供科学依据,也为中国氮素沉降网络提供关键基础数据。【方...【目的】随着人类活动引起大气活性氮排放的增加,大气氮沉降亦迅速增加,进而影响各区域生态系统。明确河北平原城市近郊农田大气氮沉降的动态变化,可以为农田氮素资源综合管理提供科学依据,也为中国氮素沉降网络提供关键基础数据。【方法】在河北省保定市河北农业大学实验教学基地进行了为期6年(2006—2011年)的湿/混合沉降监测试验以及1年(2011年)的干沉降监测试验。湿/混合沉降通过雨量器自动采集降水;干沉降中气态NH_3、HNO_3和颗粒态铵离子和硝酸根(_pNH_4^+和pNO_3^-)样品通过主动采样DELTA(DEnuder for Long-Term Atmospheric Sampling)系统采集,气态NO_2样品通过被动扩散管采集。【结果】河北保定地区多雨季节为6—9月,占全年(2006-2011年)降雨量的88.6%、81.5%、89.3%、88.9%、74.5%和83.1%;大气氮湿/混合沉降浓度冬、春季较高,夏季最低,冬春两季NH+4^+-N、NO_3^--N、TIN和TDN浓度分别占全年的74.5%、72.6%、74.1%和71.3%;氮湿/混合沉降量亦存在明显的季节性变化,夏季最大,冬季最小;各形态氮湿/混合沉降浓度高低表现为:TDN>TIN>NH+4^+-N>NO_3^--N,且与降雨量呈极显著负相关;监测区6年间平均湿/混合沉降总量为32.8 kg N·hm^(-2),其中2008年大气氮湿/混合沉降量最大,达40.4 kg N·hm^(-2),2010年大气氮湿/混合沉降量最小,为28.9 kg N·hm^(-2);大气氮湿/混合沉降中TIN占TDN沉降量75%以上,其中NH+4^+-N是TIN的主要组成部分,占其总量的56.6%—69.7%,平均为64.4%;各形态氮(NH+4^+-N、NO_3^--N、TIN和TDN)湿/混合沉降量与月降雨量、月降雨频次呈极显著正相关;大气氮干沉降中各无机氮(NH_3、NO_2、HNO_3、pNH_4^+、pNO_3^-)浓度有明显的季节性变化特征,且各形态氮的月沉降量变化趋势与氮浓度一致;总体来看,气态氮NH_3、HNO_3、NO_2及颗粒态氮pNH_4^+、pNO_3^-的年沉降量分别达到10.1、7.60、4.39、6.47及3.81 kg N·hm^(-2)。【结论】监测区大气氮沉降量受周边地区工业与当地农田施氮量共同影响,且由干湿沉降共同决定。该地区大气氮沉降量较高,2006—2011年大气湿/混合沉降总量在28.9 kg N·hm^(-2)(2010年)—40.4 kg N·hm^(-2)(2008年)之间,平均为32.8 kg N·hm^(-2);干沉降无机氮总量(2011年)为32.3 kg N·hm^(-2);干湿沉降无机氮总量(2011年)为58.6 kg N·hm^(-2)。展开更多
基金Supported by social science project of Hebei province(HB12YJ092)Development Funds of Agricultural University of Hebei(SK201111)
文摘Taking its development in Baoding City as an example, we introduced service fields of rural cooperative economic organized united association. It mainly includes setting up service platform and providing scientific and technological services; organizing economic and trade negotiation and exchange, and promoting farmer-supermarket partnership; providing financial services and solving fund-raising problems. In line with these fields, we analyzed existing problems: (i) regional development is unbalanced and organization lacks internal connection; (ii) the development in some counties (cities) is to be improved, and the promotion effect is not significant; (iii) there is shortage of talent and the innovation strength is not enough; and (iv) it lacks system and management lacks restriction mechanism. Finally, we put forward countermeasures and recommendations: strengthen propaganda and cultivate farmers' cooperative awareness; incorporate rural cooperative economic organized united association into formal system arrangement, and absorb professional talents; innovate upon organization system of rural cooperative economic organized united association and improve service methods; improve internal operating mechanism and innovate upon working contents of rural cooperative economic organized united association at new development background.
文摘【目的】随着人类活动引起大气活性氮排放的增加,大气氮沉降亦迅速增加,进而影响各区域生态系统。明确河北平原城市近郊农田大气氮沉降的动态变化,可以为农田氮素资源综合管理提供科学依据,也为中国氮素沉降网络提供关键基础数据。【方法】在河北省保定市河北农业大学实验教学基地进行了为期6年(2006—2011年)的湿/混合沉降监测试验以及1年(2011年)的干沉降监测试验。湿/混合沉降通过雨量器自动采集降水;干沉降中气态NH_3、HNO_3和颗粒态铵离子和硝酸根(_pNH_4^+和pNO_3^-)样品通过主动采样DELTA(DEnuder for Long-Term Atmospheric Sampling)系统采集,气态NO_2样品通过被动扩散管采集。【结果】河北保定地区多雨季节为6—9月,占全年(2006-2011年)降雨量的88.6%、81.5%、89.3%、88.9%、74.5%和83.1%;大气氮湿/混合沉降浓度冬、春季较高,夏季最低,冬春两季NH+4^+-N、NO_3^--N、TIN和TDN浓度分别占全年的74.5%、72.6%、74.1%和71.3%;氮湿/混合沉降量亦存在明显的季节性变化,夏季最大,冬季最小;各形态氮湿/混合沉降浓度高低表现为:TDN>TIN>NH+4^+-N>NO_3^--N,且与降雨量呈极显著负相关;监测区6年间平均湿/混合沉降总量为32.8 kg N·hm^(-2),其中2008年大气氮湿/混合沉降量最大,达40.4 kg N·hm^(-2),2010年大气氮湿/混合沉降量最小,为28.9 kg N·hm^(-2);大气氮湿/混合沉降中TIN占TDN沉降量75%以上,其中NH+4^+-N是TIN的主要组成部分,占其总量的56.6%—69.7%,平均为64.4%;各形态氮(NH+4^+-N、NO_3^--N、TIN和TDN)湿/混合沉降量与月降雨量、月降雨频次呈极显著正相关;大气氮干沉降中各无机氮(NH_3、NO_2、HNO_3、pNH_4^+、pNO_3^-)浓度有明显的季节性变化特征,且各形态氮的月沉降量变化趋势与氮浓度一致;总体来看,气态氮NH_3、HNO_3、NO_2及颗粒态氮pNH_4^+、pNO_3^-的年沉降量分别达到10.1、7.60、4.39、6.47及3.81 kg N·hm^(-2)。【结论】监测区大气氮沉降量受周边地区工业与当地农田施氮量共同影响,且由干湿沉降共同决定。该地区大气氮沉降量较高,2006—2011年大气湿/混合沉降总量在28.9 kg N·hm^(-2)(2010年)—40.4 kg N·hm^(-2)(2008年)之间,平均为32.8 kg N·hm^(-2);干沉降无机氮总量(2011年)为32.3 kg N·hm^(-2);干湿沉降无机氮总量(2011年)为58.6 kg N·hm^(-2)。
