已有许多研究证实防治农业生产过程中氮磷进入水域以及氮素进入大气环境已成为现代农业面临的最大挑战之一。为分析中国在农业源污染防控中存在问题,本文对中国和德国近年来颁布的相关法律、法规、技术标准和实施效果进行了综述和比较...已有许多研究证实防治农业生产过程中氮磷进入水域以及氮素进入大气环境已成为现代农业面临的最大挑战之一。为分析中国在农业源污染防控中存在问题,本文对中国和德国近年来颁布的相关法律、法规、技术标准和实施效果进行了综述和比较分析。研究显示,与中国相似,德国人均耕地资源比较少,以家庭农场为单元的经营方式是德国农业的主要生产方式。农业存在经营规模相对小而分散,受气象条件和市场影响风险大、利润薄、需要财政补贴才能生存等问题。对于农业源污染治理,既要实现环境目标,也要顾及农民利益、农业发展和粮食安全,难以简单采用关、停、并、转等行政指令和惩罚性措施,主要是建立和实施农业源污染管控制度。为提高农民施肥技术水平,减少农田化肥养分投入量,德国最有效的做法是在长期试验研究基础上,为农民专门设计和制作了一套比较完整的分区、分类、量化施肥技术指标和规程,这些指标简单、易记、易懂,对不同地区土壤和气候条件有良好适用性,易于推广和普及,对于提高农民施肥技术水平,实现减肥增产、减肥高产发挥了重要作用。在防治农业源氮磷进入水环境,化合态氮进入大气环境方面,德国主要做法是研究、建立和实施一系列与经济奖惩措施关联的限定性技术标准,对农田氮素养分投入量、农田氮磷盈余量、施肥期、施肥方法、种植作物类型等给出了明确的规定和技术指标。同时不断探索新的、更有效的监管和监测方法,充分发挥经济杠杆作用,鼓励、帮助和疏导农民广泛采用更先进、更精准和环境友好的替代技术。农业源污染管控制度的实施使得自20世纪80年代以来,德国农田化肥养分投入量减少了一半,以农田面积(耕地面积与长期作物面积之和)计化肥养分量从404 kg·hm^-2减少到目前的192 kg·hm^-2,仅为目前中国的53%,同期粮食单产仍提高了56%,从4779 kg·hm^-2增加到目前的7464 kg·hm^-2,比中国目前粮食单产仍然高37%。中国至今缺少为农民专门设计、适合农民认知和直接采用的量化施肥技术指标。目前也无与国家及地方政府奖惩政策关联的限定性技术标准出台,无论在全国范围,还是在重点流域,至今难以形成有制度性保障的农业源污染管控体系。在占作物总播面23.6%的蔬菜、水果、花卉等高收益作物农田上,农民盲目施肥、过量施肥情形普遍,在这类农田上,氮磷养分盈余量远超过德国肥料法规所规定的环境安全限量(50 kg N·hm^-2、10 kg P2O5·hm^-2)。比较研究还显示,实施农业源污染管控制度的核心是以创新研究带动法律、法规、相关技术标准和监管方法的出台和广泛实施。而中国近年来公益性土壤肥料专业科研机构的均质化、碎片化,以及科研机构在绩效考核中对SCI论文点数、发文量等量化指标的过分倚重,使得相关研究薄弱,亟需加以改进。展开更多
To evaluate the current state of the environmental quality of agricultural soils in Taiyuan City, a hotspot for China's industrial development, the concentrations of 8 heavy metals in soils were investigated by me...To evaluate the current state of the environmental quality of agricultural soils in Taiyuan City, a hotspot for China's industrial development, the concentrations of 8 heavy metals in soils were investigated by means of extensive sampling in farmlands, forestlands,and grasslands in the city. Statistical analyses and spatial distribution maps were used to identify the most significant heavy metal pollutants. The mean concentrations of As, Cd, Cu, Hg, Pb, Zn, Ni, and Cr were slightly higher than their background values in Taiyuan's topsoil, but were lower than the maximum permissible concentrations in the Chinese Environmental Quality Standard for agricultural soils. Farmland soils in Taiyuan had the highest average Cd, Cu, Hg, Pb, Zn, and Cr concentrations, but the As and Ni concentrations did not differ significantly among the farmland, forestland, and grasslands. Soil contamination by Cd, Cu, Hg, Pb,Zn, and Cr was mainly derived from farming practices, especially the use of sewage water for irrigation. In contrast, As and Ni might derive mainly from the soil parent material. The identification of heavy metal sources in agricultural soils may provide a basis for taking appropriate action to protect soil quality.展开更多
文摘已有许多研究证实防治农业生产过程中氮磷进入水域以及氮素进入大气环境已成为现代农业面临的最大挑战之一。为分析中国在农业源污染防控中存在问题,本文对中国和德国近年来颁布的相关法律、法规、技术标准和实施效果进行了综述和比较分析。研究显示,与中国相似,德国人均耕地资源比较少,以家庭农场为单元的经营方式是德国农业的主要生产方式。农业存在经营规模相对小而分散,受气象条件和市场影响风险大、利润薄、需要财政补贴才能生存等问题。对于农业源污染治理,既要实现环境目标,也要顾及农民利益、农业发展和粮食安全,难以简单采用关、停、并、转等行政指令和惩罚性措施,主要是建立和实施农业源污染管控制度。为提高农民施肥技术水平,减少农田化肥养分投入量,德国最有效的做法是在长期试验研究基础上,为农民专门设计和制作了一套比较完整的分区、分类、量化施肥技术指标和规程,这些指标简单、易记、易懂,对不同地区土壤和气候条件有良好适用性,易于推广和普及,对于提高农民施肥技术水平,实现减肥增产、减肥高产发挥了重要作用。在防治农业源氮磷进入水环境,化合态氮进入大气环境方面,德国主要做法是研究、建立和实施一系列与经济奖惩措施关联的限定性技术标准,对农田氮素养分投入量、农田氮磷盈余量、施肥期、施肥方法、种植作物类型等给出了明确的规定和技术指标。同时不断探索新的、更有效的监管和监测方法,充分发挥经济杠杆作用,鼓励、帮助和疏导农民广泛采用更先进、更精准和环境友好的替代技术。农业源污染管控制度的实施使得自20世纪80年代以来,德国农田化肥养分投入量减少了一半,以农田面积(耕地面积与长期作物面积之和)计化肥养分量从404 kg·hm^-2减少到目前的192 kg·hm^-2,仅为目前中国的53%,同期粮食单产仍提高了56%,从4779 kg·hm^-2增加到目前的7464 kg·hm^-2,比中国目前粮食单产仍然高37%。中国至今缺少为农民专门设计、适合农民认知和直接采用的量化施肥技术指标。目前也无与国家及地方政府奖惩政策关联的限定性技术标准出台,无论在全国范围,还是在重点流域,至今难以形成有制度性保障的农业源污染管控体系。在占作物总播面23.6%的蔬菜、水果、花卉等高收益作物农田上,农民盲目施肥、过量施肥情形普遍,在这类农田上,氮磷养分盈余量远超过德国肥料法规所规定的环境安全限量(50 kg N·hm^-2、10 kg P2O5·hm^-2)。比较研究还显示,实施农业源污染管控制度的核心是以创新研究带动法律、法规、相关技术标准和监管方法的出台和广泛实施。而中国近年来公益性土壤肥料专业科研机构的均质化、碎片化,以及科研机构在绩效考核中对SCI论文点数、发文量等量化指标的过分倚重,使得相关研究薄弱,亟需加以改进。
基金supported by the Science & Technology Pillar Program of Shanxi Province, China (No. 20121101011)the National Natural Science Foundation of China (Nos. 41271513 and 41101013)
文摘To evaluate the current state of the environmental quality of agricultural soils in Taiyuan City, a hotspot for China's industrial development, the concentrations of 8 heavy metals in soils were investigated by means of extensive sampling in farmlands, forestlands,and grasslands in the city. Statistical analyses and spatial distribution maps were used to identify the most significant heavy metal pollutants. The mean concentrations of As, Cd, Cu, Hg, Pb, Zn, Ni, and Cr were slightly higher than their background values in Taiyuan's topsoil, but were lower than the maximum permissible concentrations in the Chinese Environmental Quality Standard for agricultural soils. Farmland soils in Taiyuan had the highest average Cd, Cu, Hg, Pb, Zn, and Cr concentrations, but the As and Ni concentrations did not differ significantly among the farmland, forestland, and grasslands. Soil contamination by Cd, Cu, Hg, Pb,Zn, and Cr was mainly derived from farming practices, especially the use of sewage water for irrigation. In contrast, As and Ni might derive mainly from the soil parent material. The identification of heavy metal sources in agricultural soils may provide a basis for taking appropriate action to protect soil quality.
