Pollution and restructuring strategies of rural ecological environment in China
WANG Yongsheng1, 2, , LIU Yansui1, 2
1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China2. Center for Assessment and Research on Targeted Poverty Alleviation, CAS, Beijing 100101, China
Rural ecological environment issues in the process of rural-urban transition in China have influenced the production and daily living of residents in rural areas. This article reviews the sources and characteristics of rural environmental pollution, and proposes the restructuring strategies of rural ecological environment from the aspects of resources, production, and living. The research shows that unreasonable resource use, intensive production activities, and changed life style resulted in rural land contamination and water and air pollution. Rural environmental pollution is characterized by diversified sources, sporadic discharges, and inefficient management. These problems call for the highly efficient use of resources, cleaning of production processes, and agglomeration of living space to realize the coordination of rural production development, enhancement of quality of living, and ecological environment improvement.
Keywords：urban-rural development transformation
;
rural eco-environmental pollution
;
resource use
;
restructuring strategies
WANGYongsheng, LIUYansui. Pollution and restructuring strategies of rural ecological environment in China[J]. Progress in Geography, 2018, 37(5): 710-717 https://doi.org/10.18306/dlkxjz.2018.05.014
1 引言
1978年改革开放以来,工业化与城市化的快速发展,促使农村产业结构、就业结构和农业生产方式等发生巨大变化,中国乡村发展步入转型升级的新阶段(刘彦随, 2007),乡村地区的空间格局发生了明显的重构(Long et al, 2011),社会经济被重新塑造,乡村地域的生产功能、生活功能、生态功能和文化功能也不断发生演化(龙花楼等, 2017)。生态空间是具有重要生态功能,能为生活空间和生产空间提供生态服务和生态防护的功能区域。乡村生态环境包括资源环境、生产环境和生活环境,三者相互作用、相互影响,资源是生产和生活的基础,生产和生活行为影响自然环境。近年来,伴随着城镇化发展而产生的农业生产要素高速非农化、农村社会主体过快老弱化、村庄建设用地日益空废化、农村水土环境严重污损化以及乡村贫困片区深度贫困化等乡村衰退问题却日益凸显,亟需重视并推进乡村振兴(Liu et al, 2017),而生态环境的改善是实施乡村振兴战略的重要组成部分。党的十九大报告中提出“实施乡村振兴战略”,按照“生态宜居”的要求,推进农村生产、生活方式的生态化、绿色化,改变过往重视工业和城市污染防治,忽视农业、农村污染防治的现状,加强农村人居环境和生态环境整治,实现城乡污染治理并重。2018年中共中央办公厅、国务院办公厅印发《农村人居环境整治三年行动方案》指出,改善农村环境,建设美丽宜居乡村,是实施乡村振兴战略的重要任务,要推进农村生活垃圾和生活污水处理、开展厕所粪污治理、提升村容村貌、加强村庄规划管理、完善建设和管护机制。
Fig.1 Main sources of rural environmental pollution
2.1 资源利用
在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015)。其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016)。总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观。从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降。中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009)。矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏。地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006)。乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008)。
2.2 生产活动
农村支持城市、农业支持工业的发展方式,使得乡村成为城市与工业发展的主要资源和原产品的供给地(李玉恒等, 2013)。农业、畜牧业、水产养殖业等生产活动的加强,加重了乡村区域的生态环境压力(图1)。为提升土地产出率,农民过量使用肥料和农药等生产资料,2014年中国化肥施用总强度为333.7 kg hm-2(刘钦普, 2014),显著高于国家环保部门制定的生态县和生态乡镇化肥施用强度250 kg hm-2的常量标准。多余的肥料和农药随降水或灌溉,通过农田地表径流、农田排水和地下渗透进入附近水体,引起水体污染(Chen et al, 2014)。畜禽养殖业作为乡村经济的支柱产业,养殖规模和粪便污染物质产生量不断增加。目前,因畜禽养殖引起的单位耕地面积的氮污染平均负荷已达138.13 kg hm-2,通过堆积处直接下渗或农田施肥后间接流失,造成水体严重富营养化(杨飞等, 2013)。为满足水产品的需求,水产养殖密度超过了水体容量,大量的残剩饵料、肥料和生物代谢产物累积,降低了水体的自净能力,排出后导致周边水域氮磷负荷加重(吴伟等, 2014)。第一次全国污染源普查资料显示,农业生产(含禽畜养殖业、水产养殖业与种植业)排放的氮、磷和化学需氧量等主要污染物量,已远超过工业与生活源,成为污染源之首(杨林章, 冯彦房等, 2013)。此外,随着城市环保政策法规的逐渐加强,一些耗能高、污染重的企业转移到乡村地区,工业的废弃物或垃圾也排放到乡村地区,使得部分乡村区域环境质量低于一线城市中心,“地方病”及“癌症村”问题突出(Tilt, 2013; 李玉恒等, 2013)。
2.3 生活方式
随着农村发展、农业生产和农民生活水平的升级,农村的生活方式发生变化,生活垃圾、生活污水、旱厕粪水的持续增长及排放不当等问题受到广泛关注(图1)。调查结果显示,2011年中国农村生活垃圾产生量约为2亿吨,超过660个城市生活垃圾处理的总和(He, 2012)。乡村地区生活垃圾的主要来源包括餐饮垃圾、日常消费产生的包装物和残余物、淘汰的生活用品,清扫产生的垃圾以及农业生产垃圾,中国农村人均生活垃圾产生率为0.034~3.000 kg d-1,总体上呈现北方高于南方、东部高于西部的特点(韩智勇等, 2017)。基于全国26省的农村调研结果显示,75.9%的村落受到了不同程度的污染,生活污染对农村环境的影响最大(唐丽霞等, 2008)。农村生活污水主要来源于居民日常生活(厨房、生活洗涤和冲洗厕所)产生的污水。厨房刷锅、洗碗洗菜等产生的污水含有动植物脂肪、醋酸、碘、钠、氯等有机元素,使用洗衣粉、肥皂、洗发水等洗涤剂进行洗涤产生的污水中含磷等化学元素,排放后加重土壤和水环境的负担。农村旱厕以及厕所改造后缺少相应的处理设施,粪水中的细菌、寄生虫卵、氮磷等对乡村水质、土壤和空气产生污染。
3 乡村生态环境污染的特点
中国乡村生态环境污染形势严峻,污染类型多样,总的特点为面源污染与点源污染并存,生活污染和生产污染叠加,工业与城市等外源性污染不断向乡村地区转移,而且乡村环境治理的资金投入与技术水平低下,严重威胁乡村的可持续发展(Chen et al, 2014; Norse et al, 2015)。中国农村发展具有明显的地域特征差异,农村生态环境保护及资源可持续利用与经济发展水平脱节,总体来看,东部沿海地区和南部地区农村整体环境污染程度高于西部和北部地区。农业面源污染主要分布在以农作物种植为主的农村和以蔬菜瓜果生产为主的城市郊区,在空间上以华北和中部地区为核心,污染程度向外辐射递减,长江三角洲地区和东南沿海地区农业高度集约化发展,是高排放强度区(陈敏鹏等, 2006)。畜禽养殖造成的水污染和空气污染,主要分布在城郊及乡镇附近的集中养殖区域,四川、河南和山东是畜禽养殖的污染防控重点省份(王军霞等, 2017)。农村生活垃圾是所有农村人口聚集区的主要污染物,产生率呈现北方高于南方、东部高于西部的特点(韩智勇等, 2017)。工业三废污染主要产生在经济发展较快的城郊和乡镇。乡村生态环境系统具有综合性和复杂性,本文通过对乡村污染来源、排放以及治理特点的综述,为乡村生态环境重构提供理论支撑。
农业生产过程的清洁化对于提升农村生态环境质量具有重要作用,尤其要加强农业生产、畜禽养殖和水产养殖绿色技术和清洁模式的引入,降低生产投入、阻控污染过程、循环利用废弃物(图2),有效削减农业生产过程中的污染排放。在作物产量不减少的前提下,如何降低农业化学物质的使用,提高农业生产资料的利用效率是关键。河北曲周县依托科技小院模式,应用“土壤-作物系统综合管理”理论和技术,全县粮食单产实现了试验基地产量水平的79.6%,粮食总产增长37%,农民收入增长79%(Zhang et al, 2016),同时还可提高氮肥利用效率,减少活性氮损失和温室气体的排放,有力地保护了生态环境(Chen et al, 2014)。随着信息化和物联网技术的发展,精准农业在平原农区和农场中不断应用,依靠信息技术、装备技术、生物技术,通过节省资源投入、减少资源损失、提高利用效率,降低农业生产对土壤和水体环境的污染,实现作物产量和农业环境质量的双赢(王永生等, 2016)。从厂区选址、饲喂过程、粪水处理等方面入手,实现畜禽养殖的清洁化。为降低乡镇企业的污染,应通过合理布局、调整产业结构和推进清洁生产,使企业的布局合理,污染源相对集中,减少污染产业,同时引进低污染生产工艺,解决乡镇企业对农村生态环境的污染。同样,对畜禽养殖业和水产养殖业的选址、饲喂过程、粪水处理等环节严格把关。除了从源头减量控制外,实施过程阻断和废弃物的循环利用也是防治环境污染的途径。杨林章, 施卫明等(2013)提出从污染物的源头减量入手,根据治理区域的污染汇聚特征进行过程阻断,再结合污水及废弃物中养分的循环利用减少污染物的产生量。该技术使稻田由原来的污染源变成污染物的消纳汇,不但可以有效防控农村面源污染的产生和发展,而且还能有效地削减农村面源污染的负荷。
4.3 生活方式集约化
乡村生活空间的分散、生活方式的差异、污染排放的随机性以及基础设施的落后,阻碍了乡村生态环境的高效整治,需通过生活空间的集聚、生活污染的集中处理和基础设施的改善得到解决。根据空间优化、组织有序和产业高效的整治理念,促使乡村生活空间集聚,由“生活”功能转向“生活、生产、生态的多功能”(刘彦随等, 2009)。农村的空心化与宅基地的废弃化既是生活空间的问题,也是生态空间问题,还可间接导致生产空间问题。山东省禹城市通过迁村并居,退宅还田工程,将农田生态系统嵌入村庄绿地系统,实现了村庄整治增地和现代农业发展;通过空心村整治、中心村建设和中心镇转移的地域模式,通过合村并居,适当加强乡村聚落的空间集聚,使得群众的居住环境和生活环境得到明显改善(Liu et al, 2014; 龙花楼等, 2017)。针对乡村生活污水和垃圾污染生态环境问题,可通过城乡一体化处理或就地集中处理模式来解决,在村落人口密度和经济水平较低的偏远农村,可采用分散式家庭处理模式(顾霖等, 2016; 韩智勇等, 2017)。在条件允许的部分村庄,逐步开展气代煤、电代煤的冬季取暖措施,改善冬季雾霾状况。将农村环境治理与美丽乡村及异地扶贫搬迁等工程相结合,实现新农村基础设施的改善,乡村居民的集中生活,村容村貌的治理。促使乡村走生产发展、生活富裕、生态良好的文明发展道路,为人民创造良好生产生活环境,为生态安全作出贡献。
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The politics of industrial pollution in rural China
[J]. The Journal of Peasant Studies, 40(6): 1147-1164.
After more than three decades of extremely rapid industrial growth, China faces an environmental crisis. The rural industrial sector, which includes millions of loosely regulated factories and employs hundreds of millions of workers, is a major focal point of this crisis. This paper provides a critical review of scholarship on industrial pollution in rural China and advances a new framework for thinking about the topic as a political domain with three inter-related parts: 61 The politics of knowledge: What do rural citizens know about environmental contamination, and how do they know they know it? What sources of information are available to the public regarding pollution incidents? How does uncertainty about pollution sources and severity, as well as the potential links to health risks, shape rural peoples' experience of pollution? 61 The politics of action: What strategies do individuals, communities and civil society organizations use to combat pollution? What outcomes are associated with such strategies? 61 The politics of regulation: How are national laws and policies regarding pollution control implemented in rural areas? How do agencies and enforcement officials balance the competing objectives of environmental protection and economic growth?The paper concludes by considering the implications of this framework for how scholars understand industrial pollution in rural China and briefly discussing a future research agenda for this field.
Abstract Uncovering magnitude, trend, and spatial pattern of land cover/land use changes (LCLUC) is crucial for understanding mechanisms of LCLUC and assisting land use planning and conservation. China has been undergoing unprecedented economic growth, massive rural-to-urban migration, and large-scale policy-driven ecological restoration, and therefore encountering enormous LCLUC in recent decades. However, comprehensive understandings of spatiotemporal LCLUC dynamics and underlying mechanisms are still lacking. Based on classification of annual LCLU maps from MODIS satellite imagery, we proposed a land change detection method to capture significant land change hotspots over Northern China during 2001-2013, and further analyzed temporal trends and spatial patterns of LCLUC. We found rapid decline of agricultural land near urban was predominantly caused by urban expansion. The process was especially strong in North China Plain with 14,057090009km 2 of urban gain and -21,017090009km 2 of agricultural land loss. To offset the loss of agricultural land, Northeast China Plain and Xinjiang were reclaimed. Substantial recovery of forests (49,908090009km 2 ) and closed shrubland (60,854090009km 2 ) occurred in mountainous regions due to abandoned infertile farmland, secondary succession, and governmental conservation policies. The spatial patterns and trends of LCLUC in Northern China provide information to support effective environmental policies towards sustainable development.
[39]
WangM, WebberM, FinlaysonB, et al.2008.
Rural industries and water pollution in China
[J]. Journal of Environmental Management, 86(4): 648-659.
Abstract Water pollution from small rural industries is a serious problem throughout China. Over half of all river sections monitored for water quality are rated as being unsafe for human contact, and this pollution is estimated to cost several per cent of GDP. While China has some of the toughest environmental protection laws in the world, the implementation of these laws in rural areas is not effective. This paper explains the reasons for this implementation gap. It argues that the factors that have underpinned the economic success of rural industry are precisely the same factors that cause water pollution from rural industry to remain such a serious problem in China. This means that the control of rural water pollution is not simply a technical problem of designing a more appropriate governance system, or finding better policy instruments or more funding. Instead, solutions lie in changes in the model that underpins rural development in China.
Land and water resources are two basic factors for sustaining the development of agriculture. The two are scare resources with rapid social economic development gradually, especially in Mu Us Sandy Land (MUSL) with severe desertification. Arsenic sandstone is a special rock type of MUSL with strong water holding capacity, which appropriately makes up the shortage of sand on water and fertilizer losing. Based on it, a comprehensive framework on land-water resources development was proposed including engineering treatment measures, appropriate irrigation management and farming measures after a series of experiments designed for sandy land treated with arsenic sandstone. Results of the experiments showed that both water content and fertility increased after using a 1:2 arsenic sandstone/sand ratio by mixing both together. An area of 151.3ha arable land was newly-increased by applying the framework in Dajihan village sandy land of the MUSL, which created direct economic efficiency of 14.1 million Yuan RMB by tomato planting, and obtained 61% of water saving effect compare to untreated sand. The application of the framework in Dajihan village also got huge social-ecological efficiency such as on soil and water conservation, sand-fixing and forming high quality farmland. The framework helped to completed the process from soil synthesize to agricultural production, then to real soil, which transformed the traditional sandy land treatment to sandy land development, and was proved to be practicable and sustainable in local sandy agriculture.
[41]
Zhang WF, Cao GX, Li XL, et al.2016.
Closing yield gaps in China by empowering smallholder farmers
Sustainably feeding the world’s growing population is a challenge, and closing yield gaps (that is, differences between farmers’ yields and what are attainable for a given region) is a vital strategy to address this challenge. The magnitude of yield gaps is particularly large in developing countries where smallholder farming dominates the agricultural landscape. Many factors and constraints interact to limit yields, and progress in problem-solving to bring about changes at the ground level is rare. Here we present an innovative approach for enabling smallholders to achieve yield and economic gains sustainably via the Science and Technology Backyard (STB) platform. STB involves agricultural scientists living in villages among farmers, advancing participatory innovation and technology transfer, and garnering public and private support. We identified multifaceted yield-limiting factors involving agronomic, infrastructural, and socioeconomic conditions. When these limitations and farmers’ concerns were addressed, the farmers adopted recommended management practices, thereby improving production outcomes. In one region in China, the five-year average yield increased from 67.9% of the attainable level to 97.0% among 71 leading farmers, and from 62.8% to 79.6% countywide (93,074 households); this was accompanied by resource and economic benefits.
Reduce-retain-reuse-restore technology for the controlling the agricultural non-point source pollution in countryside in China: General countermeasures and technologies
[J]. Journal of Agro-Environment Science, 32(1): 1-8.]
Agriculture faces great challenges to ensure global food security by increasing yields while reducing environmental costs. Here we address this challenge by conducting a total of 153 site-year field experiments covering the main agro-ecological areas for rice, wheat and maize production in China. A set of integrated soil-crop system management practices based on a modern understanding of crop ecophysiology and soil biogeochemistry increases average yields for rice, wheat and maize from 7.2 million grams per hectare (Mg ha), 7.2 Mg haand 10.5 Mg hato 8.5 Mg ha, 8.9 Mg haand 14.2 Mg ha, respectively, without any increase in nitrogen fertilizer. Model simulation and life-cycle assessment show that reactive nitrogen losses and greenhouse gas emissions are reduced substantially by integrated soil-crop system management. If farmers in China could achieve average grain yields equivalent to 80% of this treatment by 2030, over the same planting area as in 2012, total production of rice, wheat and maize in China would be more than enough to meet the demand for direct human consumption and a substantially increased demand for animal feed, while decreasing the environmental costs of intensive agriculture.
[28]
He PJ.2012.
Municipal solid waste in rural areas of developing country: Do we need special treatment mode
Post-Mao rural reform has stimulated farmers' incentives for agricultural production. Yet, the short period of 15 years' land tenure, coupled with the ambiguous land property rights between collectives and individual households has also encouraged short-sighted decisions and the irresponsible use of land resources. Capital investment in farmland, and maintenance of irrigation facilities have been neglected. Farmers are “digging” soil and land resources for short and immediate benefit. In addition, low profit to grain production has the disadvantage of protecting arable land from being used for another purpose, also over-fragmented land with increased ridges and ditches has hampered—the function of irrigation and drainage and aggravated the impact of natural disaster. As a consequence, all this has led to the degradation of China's agro-ecological environment. The situation is deteriorating. This paper describes the links between reformed land tenure systems and irresponsible farming as well as degraded agro-environment, some policy remedies are suggested.
Ecological restoration of mineland with particular reference to the metalliferous mine wasteland in China: A review of research and practice
2
2006
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
Urban-rural interaction patterns and dynamic land use: Implications for urban-rural integration in China
1
2012
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
Implications of land-use change in rural China: A case study of Yucheng, Shandong province
... 农村支持城市、农业支持工业的发展方式,使得乡村成为城市与工业发展的主要资源和原产品的供给地(李玉恒等, 2013).农业、畜牧业、水产养殖业等生产活动的加强,加重了乡村区域的生态环境压力(图1).为提升土地产出率,农民过量使用肥料和农药等生产资料,2014年中国化肥施用总强度为333.7 kg hm-2(刘钦普, 2014),显著高于国家环保部门制定的生态县和生态乡镇化肥施用强度250 kg hm-2的常量标准.多余的肥料和农药随降水或灌溉,通过农田地表径流、农田排水和地下渗透进入附近水体,引起水体污染(Chen et al, 2014).畜禽养殖业作为乡村经济的支柱产业,养殖规模和粪便污染物质产生量不断增加.目前,因畜禽养殖引起的单位耕地面积的氮污染平均负荷已达138.13 kg hm-2,通过堆积处直接下渗或农田施肥后间接流失,造成水体严重富营养化(杨飞等, 2013).为满足水产品的需求,水产养殖密度超过了水体容量,大量的残剩饵料、肥料和生物代谢产物累积,降低了水体的自净能力,排出后导致周边水域氮磷负荷加重(吴伟等, 2014).第一次全国污染源普查资料显示,农业生产(含禽畜养殖业、水产养殖业与种植业)排放的氮、磷和化学需氧量等主要污染物量,已远超过工业与生活源,成为污染源之首(杨林章, 冯彦房等, 2013).此外,随着城市环保政策法规的逐渐加强,一些耗能高、污染重的企业转移到乡村地区,工业的废弃物或垃圾也排放到乡村地区,使得部分乡村区域环境质量低于一线城市中心,“地方病”及“癌症村”问题突出(Tilt, 2013; 李玉恒等, 2013). ...
中国农业和农村污染的清单分析与空间特征识别
1
2006
... 中国乡村生态环境污染形势严峻,污染类型多样,总的特点为面源污染与点源污染并存,生活污染和生产污染叠加,工业与城市等外源性污染不断向乡村地区转移,而且乡村环境治理的资金投入与技术水平低下,严重威胁乡村的可持续发展(Chen et al, 2014; Norse et al, 2015).中国农村发展具有明显的地域特征差异,农村生态环境保护及资源可持续利用与经济发展水平脱节,总体来看,东部沿海地区和南部地区农村整体环境污染程度高于西部和北部地区.农业面源污染主要分布在以农作物种植为主的农村和以蔬菜瓜果生产为主的城市郊区,在空间上以华北和中部地区为核心,污染程度向外辐射递减,长江三角洲地区和东南沿海地区农业高度集约化发展,是高排放强度区(陈敏鹏等, 2006).畜禽养殖造成的水污染和空气污染,主要分布在城郊及乡镇附近的集中养殖区域,四川、河南和山东是畜禽养殖的污染防控重点省份(王军霞等, 2017).农村生活垃圾是所有农村人口聚集区的主要污染物,产生率呈现北方高于南方、东部高于西部的特点(韩智勇等, 2017).工业三废污染主要产生在经济发展较快的城郊和乡镇.乡村生态环境系统具有综合性和复杂性,本文通过对乡村污染来源、排放以及治理特点的综述,为乡村生态环境重构提供理论支撑. ...
中国农业和农村污染的清单分析与空间特征识别
1
2006
... 中国乡村生态环境污染形势严峻,污染类型多样,总的特点为面源污染与点源污染并存,生活污染和生产污染叠加,工业与城市等外源性污染不断向乡村地区转移,而且乡村环境治理的资金投入与技术水平低下,严重威胁乡村的可持续发展(Chen et al, 2014; Norse et al, 2015).中国农村发展具有明显的地域特征差异,农村生态环境保护及资源可持续利用与经济发展水平脱节,总体来看,东部沿海地区和南部地区农村整体环境污染程度高于西部和北部地区.农业面源污染主要分布在以农作物种植为主的农村和以蔬菜瓜果生产为主的城市郊区,在空间上以华北和中部地区为核心,污染程度向外辐射递减,长江三角洲地区和东南沿海地区农业高度集约化发展,是高排放强度区(陈敏鹏等, 2006).畜禽养殖造成的水污染和空气污染,主要分布在城郊及乡镇附近的集中养殖区域,四川、河南和山东是畜禽养殖的污染防控重点省份(王军霞等, 2017).农村生活垃圾是所有农村人口聚集区的主要污染物,产生率呈现北方高于南方、东部高于西部的特点(韩智勇等, 2017).工业三废污染主要产生在经济发展较快的城郊和乡镇.乡村生态环境系统具有综合性和复杂性,本文通过对乡村污染来源、排放以及治理特点的综述,为乡村生态环境重构提供理论支撑. ...
Spatially differentiated trends in urbanization, agricultural land abandonment and reclamation, and woodland recovery in Northern China
1
2016
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
中国农村污染状况调查与分析: 来自全国141个村的数据
2
2008
... 随着农村发展、农业生产和农民生活水平的升级,农村的生活方式发生变化,生活垃圾、生活污水、旱厕粪水的持续增长及排放不当等问题受到广泛关注(图1).调查结果显示,2011年中国农村生活垃圾产生量约为2亿吨,超过660个城市生活垃圾处理的总和(He, 2012).乡村地区生活垃圾的主要来源包括餐饮垃圾、日常消费产生的包装物和残余物、淘汰的生活用品,清扫产生的垃圾以及农业生产垃圾,中国农村人均生活垃圾产生率为0.034~3.000 kg d-1,总体上呈现北方高于南方、东部高于西部的特点(韩智勇等, 2017).基于全国26省的农村调研结果显示,75.9%的村落受到了不同程度的污染,生活污染对农村环境的影响最大(唐丽霞等, 2008).农村生活污水主要来源于居民日常生活(厨房、生活洗涤和冲洗厕所)产生的污水.厨房刷锅、洗碗洗菜等产生的污水含有动植物脂肪、醋酸、碘、钠、氯等有机元素,使用洗衣粉、肥皂、洗发水等洗涤剂进行洗涤产生的污水中含磷等化学元素,排放后加重土壤和水环境的负担.农村旱厕以及厕所改造后缺少相应的处理设施,粪水中的细菌、寄生虫卵、氮磷等对乡村水质、土壤和空气产生污染. ...
... 农业生产过程的清洁化对于提升农村生态环境质量具有重要作用,尤其要加强农业生产、畜禽养殖和水产养殖绿色技术和清洁模式的引入,降低生产投入、阻控污染过程、循环利用废弃物(图2),有效削减农业生产过程中的污染排放.在作物产量不减少的前提下,如何降低农业化学物质的使用,提高农业生产资料的利用效率是关键.河北曲周县依托科技小院模式,应用“土壤-作物系统综合管理”理论和技术,全县粮食单产实现了试验基地产量水平的79.6%,粮食总产增长37%,农民收入增长79%(Zhang et al, 2016),同时还可提高氮肥利用效率,减少活性氮损失和温室气体的排放,有力地保护了生态环境(Chen et al, 2014).随着信息化和物联网技术的发展,精准农业在平原农区和农场中不断应用,依靠信息技术、装备技术、生物技术,通过节省资源投入、减少资源损失、提高利用效率,降低农业生产对土壤和水体环境的污染,实现作物产量和农业环境质量的双赢(王永生等, 2016).从厂区选址、饲喂过程、粪水处理等方面入手,实现畜禽养殖的清洁化.为降低乡镇企业的污染,应通过合理布局、调整产业结构和推进清洁生产,使企业的布局合理,污染源相对集中,减少污染产业,同时引进低污染生产工艺,解决乡镇企业对农村生态环境的污染.同样,对畜禽养殖业和水产养殖业的选址、饲喂过程、粪水处理等环节严格把关.除了从源头减量控制外,实施过程阻断和废弃物的循环利用也是防治环境污染的途径.杨林章, 施卫明等(2013)提出从污染物的源头减量入手,根据治理区域的污染汇聚特征进行过程阻断,再结合污水及废弃物中养分的循环利用减少污染物的产生量.该技术使稻田由原来的污染源变成污染物的消纳汇,不但可以有效防控农村面源污染的产生和发展,而且还能有效地削减农村面源污染的负荷. ...
中国水资源状况与水资源安全问题分析
1
2009
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
中国水资源状况与水资源安全问题分析
1
2009
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
Investigation on emission factors of particulate matter and gaseous pollutants from crop residue burning
1
2008
... 在城镇化进程中,劳动力、资源及产品等要素的相互流动与聚集,导致城乡间水土等资源环境变化(Li, 2012),开发区、工业园、大学新区的大量建设,使优质耕地资源被挤占(佘之祥, 2015).其次,随着城镇就业机会和收入的增加,农业生产成本的提高和农业收入的降低,农村人口逐渐向非农化转移,导致农村空心化,宅基地闲置空废与土地撂荒等问题(刘彦随, 2015; Wang et al, 2016).总的来说,土地资源破坏和污损,使土地质量不断下降;农村住宅的分散布局与废弃院落的破败荒芜破坏乡村景观.从水资源方面来看,中国人均水资源占有量低,但水资源浪费、水资源利用效率低下及污染问题严重,导致水资源危机和生态环境质量下降.中国农业灌溉利用系数仅有0.3~0.4,工业万元产值用水量是发达国家的10~20倍,而且重复利用率低,生活用水跑、冒、滴、漏损失率为15%~20%;农业与工业生产、居民生活引起水质污染问题严重(张利平等, 2009).矿产资源是工农业的物质基础,由于开采力度不断加大,导致矿山开采对土地和生态环境造成了严重的破坏.地形地貌与景观破碎化,极易诱发泥石流、荒漠化等次生环境灾害;矿山废弃土地的质量低下,重金属离子污染土壤,进入食物链后对人体造成严重危害(Li, 2006).乡村地区的秸秆资源丰富,但资源化利用率较低,大部分农作物秸秆直接焚烧,不仅造成氮、磷、钾等营养元素的资源浪费,而且焚烧产生大量气态污染物(CO、SO2、NOx等)及颗粒物,容易引起大面积的空气污染(Cao et al, 2008). ...
Producing more grain with lower environmental costs
3
2014
... 农村支持城市、农业支持工业的发展方式,使得乡村成为城市与工业发展的主要资源和原产品的供给地(李玉恒等, 2013).农业、畜牧业、水产养殖业等生产活动的加强,加重了乡村区域的生态环境压力(图1).为提升土地产出率,农民过量使用肥料和农药等生产资料,2014年中国化肥施用总强度为333.7 kg hm-2(刘钦普, 2014),显著高于国家环保部门制定的生态县和生态乡镇化肥施用强度250 kg hm-2的常量标准.多余的肥料和农药随降水或灌溉,通过农田地表径流、农田排水和地下渗透进入附近水体,引起水体污染(Chen et al, 2014).畜禽养殖业作为乡村经济的支柱产业,养殖规模和粪便污染物质产生量不断增加.目前,因畜禽养殖引起的单位耕地面积的氮污染平均负荷已达138.13 kg hm-2,通过堆积处直接下渗或农田施肥后间接流失,造成水体严重富营养化(杨飞等, 2013).为满足水产品的需求,水产养殖密度超过了水体容量,大量的残剩饵料、肥料和生物代谢产物累积,降低了水体的自净能力,排出后导致周边水域氮磷负荷加重(吴伟等, 2014).第一次全国污染源普查资料显示,农业生产(含禽畜养殖业、水产养殖业与种植业)排放的氮、磷和化学需氧量等主要污染物量,已远超过工业与生活源,成为污染源之首(杨林章, 冯彦房等, 2013).此外,随着城市环保政策法规的逐渐加强,一些耗能高、污染重的企业转移到乡村地区,工业的废弃物或垃圾也排放到乡村地区,使得部分乡村区域环境质量低于一线城市中心,“地方病”及“癌症村”问题突出(Tilt, 2013; 李玉恒等, 2013). ...
... 中国乡村生态环境污染形势严峻,污染类型多样,总的特点为面源污染与点源污染并存,生活污染和生产污染叠加,工业与城市等外源性污染不断向乡村地区转移,而且乡村环境治理的资金投入与技术水平低下,严重威胁乡村的可持续发展(Chen et al, 2014; Norse et al, 2015).中国农村发展具有明显的地域特征差异,农村生态环境保护及资源可持续利用与经济发展水平脱节,总体来看,东部沿海地区和南部地区农村整体环境污染程度高于西部和北部地区.农业面源污染主要分布在以农作物种植为主的农村和以蔬菜瓜果生产为主的城市郊区,在空间上以华北和中部地区为核心,污染程度向外辐射递减,长江三角洲地区和东南沿海地区农业高度集约化发展,是高排放强度区(陈敏鹏等, 2006).畜禽养殖造成的水污染和空气污染,主要分布在城郊及乡镇附近的集中养殖区域,四川、河南和山东是畜禽养殖的污染防控重点省份(王军霞等, 2017).农村生活垃圾是所有农村人口聚集区的主要污染物,产生率呈现北方高于南方、东部高于西部的特点(韩智勇等, 2017).工业三废污染主要产生在经济发展较快的城郊和乡镇.乡村生态环境系统具有综合性和复杂性,本文通过对乡村污染来源、排放以及治理特点的综述,为乡村生态环境重构提供理论支撑. ...
... 农业生产过程的清洁化对于提升农村生态环境质量具有重要作用,尤其要加强农业生产、畜禽养殖和水产养殖绿色技术和清洁模式的引入,降低生产投入、阻控污染过程、循环利用废弃物(图2),有效削减农业生产过程中的污染排放.在作物产量不减少的前提下,如何降低农业化学物质的使用,提高农业生产资料的利用效率是关键.河北曲周县依托科技小院模式,应用“土壤-作物系统综合管理”理论和技术,全县粮食单产实现了试验基地产量水平的79.6%,粮食总产增长37%,农民收入增长79%(Zhang et al, 2016),同时还可提高氮肥利用效率,减少活性氮损失和温室气体的排放,有力地保护了生态环境(Chen et al, 2014).随着信息化和物联网技术的发展,精准农业在平原农区和农场中不断应用,依靠信息技术、装备技术、生物技术,通过节省资源投入、减少资源损失、提高利用效率,降低农业生产对土壤和水体环境的污染,实现作物产量和农业环境质量的双赢(王永生等, 2016).从厂区选址、饲喂过程、粪水处理等方面入手,实现畜禽养殖的清洁化.为降低乡镇企业的污染,应通过合理布局、调整产业结构和推进清洁生产,使企业的布局合理,污染源相对集中,减少污染产业,同时引进低污染生产工艺,解决乡镇企业对农村生态环境的污染.同样,对畜禽养殖业和水产养殖业的选址、饲喂过程、粪水处理等环节严格把关.除了从源头减量控制外,实施过程阻断和废弃物的循环利用也是防治环境污染的途径.杨林章, 施卫明等(2013)提出从污染物的源头减量入手,根据治理区域的污染汇聚特征进行过程阻断,再结合污水及废弃物中养分的循环利用减少污染物的产生量.该技术使稻田由原来的污染源变成污染物的消纳汇,不但可以有效防控农村面源污染的产生和发展,而且还能有效地削减农村面源污染的负荷. ...
Municipal solid waste in rural areas of developing country: Do we need special treatment mode
1
2012
... 随着农村发展、农业生产和农民生活水平的升级,农村的生活方式发生变化,生活垃圾、生活污水、旱厕粪水的持续增长及排放不当等问题受到广泛关注(图1).调查结果显示,2011年中国农村生活垃圾产生量约为2亿吨,超过660个城市生活垃圾处理的总和(He, 2012).乡村地区生活垃圾的主要来源包括餐饮垃圾、日常消费产生的包装物和残余物、淘汰的生活用品,清扫产生的垃圾以及农业生产垃圾,中国农村人均生活垃圾产生率为0.034~3.000 kg d-1,总体上呈现北方高于南方、东部高于西部的特点(韩智勇等, 2017).基于全国26省的农村调研结果显示,75.9%的村落受到了不同程度的污染,生活污染对农村环境的影响最大(唐丽霞等, 2008).农村生活污水主要来源于居民日常生活(厨房、生活洗涤和冲洗厕所)产生的污水.厨房刷锅、洗碗洗菜等产生的污水含有动植物脂肪、醋酸、碘、钠、氯等有机元素,使用洗衣粉、肥皂、洗发水等洗涤剂进行洗涤产生的污水中含磷等化学元素,排放后加重土壤和水环境的负担.农村旱厕以及厕所改造后缺少相应的处理设施,粪水中的细菌、寄生虫卵、氮磷等对乡村水质、土壤和空气产生污染. ...
Household land tenure reform in China: Its impact on farming land use and agro-environment
, 刘彦随
