Does extensification lead to enhanced provision of ecosystems services from soils in UK agriculture?

Extensification is offered as a management strategy to reduce the perceived negative effects of intensive agricultural management, e.g. nutrient loss through leaching, emissions of the greenhouse gas N₂O, loss of soil carbon through carbon dioxide emissions, increased nutrient, carbon and sediment loading to surface water, and reduced biodiversity. As part of managed extensification implemented under the European Union's Common Agricultural Policy intensively managed land use types (arable and grassland) are taken out of production for either 5, 7 or 10 years in the UK. The ultimate objective is to establish species-rich grassland (SRG) to which limited or no fertiliser is applied, which attracts subsidy payments under the European Agricultural Fund for Rural Development. There is little scientific evidence for the anticipated environmental benefits of these newly created SRGs. The legacy of intensive management on soils is likely to limit ecosystem service (ES) provision from former intensively managed sites for many decades following extensification and this commentary addresses this issue. Clearly, programmes of long-term experimental research are needed to quantify the environmental and economic benefits of current extensification schemes in UK agriculture in order to determine whether the benefits for ES delivered by soils out-weigh the costs in terms of loss of production.     

The Dynamic Competitiveness of U.S. Agricultural and Forest Carbon Sequestration

Society is increasingly turning attention toward greenhouse gas emission control with for example the Kyoto Protocol has entered into force. Since many of the emissions come from energy use, high cost strategies might be required until new technological developments reduce fossil fuel dependency or increase energy utilization efficiency. On the other hand biologically based strategies may be used to offset energy related emissions. Agricultural soil and forestry are among the largest carbon reservoirs on the planet; therefore, agricultural and forest activities may help to reduce the costs of greenhouse gas emission mitigation. However, sequestration exhibits permanence related characteristics that may influence this role. We examine the dynamic role of carbon sequestration in the agricultural and forest sectors can play in mitigation. A 100-year mathematical programming model, depicting U.S. agricultural and forest sectoral activities including land transfers and greenhouse gas consequences is applied to simulate potential mitigation response. The results show that at low cost and in the near term agricultural soil and forest management are dominant sectoral responses. At higher prices and in the longer term biofuels and afforestation take over. Our results reveal that the agricultural and forest sector carbon sequestration may serve as an important bridge to the future helping to hold costs down until energy emissions related technology develops.     

UK land use and soil carbon sequestration

This review explores the role of land use and land use change as a determinant of the soil's ability to sequester and store carbon in the UK. Over 95 percent of the UK land carbon stock is located in soils which are subjected to a range of land uses and global changes. Land use change can result in rapid soil loss of carbon from peatlands, grasslands, plantation forest and native woodland. Soil carbon accumulates more slowly (decadal) but gains can be made when croplands are converted to grasslands, plantation forest or native woodland. The need for land for food production and renewable forms of energy could have considerable influence on UK soil carbon storage in the future. There is a need to recognise the risk of soil carbon losses occurring when land use change to increase carbon storage is offset by compensatory land use conversions elsewhere that result in net carbon release. The protection of peatland and other organic soil carbon stocks, and the management of cropland, grassland and forest soils to increase carbon sequestration, will be crucial to the maintenance of the UK carbon balance. It will be necessary to develop policy to balance trade-offs between soil carbon gains with other land use priorities. These include the sustainable production of food, bio-energy and fibre crops and livestock, water quality and hydrology, greenhouse gas emission control and waste management, all of which are underpinned by the soil.     

Green Light for Green Agricultural Policies? An Analysis at Regional and Global Scales

This paper analyses the effects of introducing biodiversity‐targeted ecological focus area (EFA) requirements on all farms with arable land in the EU by quantifying their global, regional, economic and environmental impacts in a mutually consistent way. To capture these impacts, different spatial scales need to be considered – ranging from on‐farm decisions regarding the EFA in the EU, to supply response around the world. In order to address this challenge, we combine the supply side of the CAPRI model, which offers high spatial, farm and policy resolution in the EU, with the GTAP model of global trade and land use. Both models are linked through a multi‐product, restricted‐revenue function for the EU crop sector. The results predict improved environmental status in the high‐yielding regions of the EU. However, output price increases lead to intensification in the more marginal areas of the EU where little or no additional land is taken out of production. The decrease in arable land in the EU is partially compensated by an increase of crop land, as well as increased fertiliser applications, in other regions of the globe. Thus, the improvement of environmental status in the EU comes at the price of global intensification, as well as the loss of forest and grassland areas outside the EU. Overall, we find that every hectare of land that is taken out of production in the EU increases greenhouse gas emissions in the rest of the world by 20.8 tonnes CO₂ equivalent.     

Persistence of cattle ranching in the Brazilian Amazon: A spatial analysis of the rationale for beef production

Fed by demand for beef within Brazil and in global markets, the Brazilian herd grew from 147 million head of cattle in 1990 to ≈200 million in 2007. Eighty-three percent of this expansion occurred in the Amazon and this trend is expected to continue as the industry bounces back from a recent agricultural downturn. Intensification of the cattle industry has been suggested as one way to reduce pressure on forest margins and spare land for soybean or sugarcane production, and is the cornerstone of Brazil's plan for mitigation of greenhouse gas emissions. To this end, federal credit programs and research and development activities in Brazil are aligning to support intensification goals, but there is no guarantee that this push for intensification will decrease the demand for land at the forest margin and as result curb CO₂ emissions from deforestation. In this paper we use a spatially explicit rent model which incorporates the local effects of biophysical characteristics, infrastructure, land prices, and distance to markets and slaughterhouses to calculate 30-year Net Present Values (NPVs) of extensive cattle ranching across the Brazilian Amazon. We use the model to ask where extensive ranching is profitable and how land acquisition affects profitability. We estimate that between 17% and 80% of land in the Amazon would have moderate to high NPVs when ranched extensively if it were settled, i.e. if the rancher does not buy the land but acquires it through land grabbing. In addition, we estimate that between 9% and 13% of land in the Amazon is vulnerable to speculation (i.e. areas with positive NPVs only if land is settled and not purchased), which suggests that land speculation is an important driver of extensive ranching profitability, and may continue to be in the future. These results suggest that pro-intensification policies such as credit provision for improved pasture management and investment in more intensive production systems must be accompanied by implementation and enforcement of policies that alter the incentives to clear forest for pasture, discourage land speculation, and increase accountability for land management practices if intensification of the cattle sector is to deter new deforestation and displace production from low-yield, extensive cattle production systems in frontier regions of the Brazilian Amazon.     

宁南上黄村乡村土地景观格局优化与生态经济功能区研究

研究目的：以宁夏固原市上黄村不同时期土地利用现状图为基础,研究黄土高原乡村尺度上的土地利用变化与生态功能区规划。研究方法：RS/GIS技术与数理统计法。研究结果：近30年来上黄小流域土地利用发生了巨大的变化,主要表现为林草地面积大幅度增长,坡耕地面积减少和果园面积逐年扩大;上黄村可划分为生态环境保护区、旱作农业区和高效生态农业区三个功能区。研究结论：在研究土地利用变化的基础上,进行土地结构优化调整与生态功能区划,对黄土高原半干旱生态严重退化区的生态环境进行修复与可持续发展具有重要的理论和实践意义。     

Cross compliance and the protection of grassland - Illustrative analyses of land use transitions between permanent grassland and arable land in German regions

Permanent grassland combines various ecological functions in terms of nature, soil, water and climate protection. Conversion of grassland to arable land is accompanied by a diminution of these functions. Various developments have led to increased pressure on the EU grassland area. With cross compliance, the EU sets minimum standards for the protection of the ratio of permanent grassland. However, this requirement alone does not ensure the preservation of grassland on sensitive sites, such as water or nature conservation areas or land on organic soils or on steep hills.This paper deals with land use changes between grassland and arable land. For this purpose we analyse data of the EU's Integrated Administration and Control System (IACS) from four German federal states. The described methodology allows to identify gross changes of land use and to distinguish between conversion of permanent grassland and “loss” due to “deactivation” at a highly disaggregated level. Merging IACS-data with further spatially explicit data provides a picture of land use transitions in ecologically sensitive areas and enables conclusions to be drawn about the effectiveness of protection measures.     

Mapping changes in land use/land cover and prediction of future extension of bowé in Benin,West Africa

Desertification and land degradation are worldwide problems affecting soil, vegetation and the livelihoods of rural populations. Bowal (plural bowé) is a particular form of degraded land that occurs in tropical regions and leads to the exposure of ferricretes, which are unsuitable for farming. Bowé are more common on farmland and degraded savanna. Changes in land use/land cover were used to map a region of 6.7 million ha in northern Benin, West Africa in 1975, 1990 and 2010. The changes observed during these periods (1975–1990, 1990–2010 and 1975–2010) were used to predict the occurrence of bowé in the period up to 2050 using Markovian chain analysis. The results showed a considerable change in land use/land cover during the three periods. The types of land on which bowé occur (farmland and degraded savanna) increased in northern Benin by 5.4% per year during the period 1975–1990 and 9.5% per year during the periods 1990–2010, while the natural vegetation (forest, woodland and tree savanna) decreased by the same amount. The future scenarios also predicted the same trend. In the period 1975–1990, 1.28 million ha (26%) of natural vegetation was converted to degraded savanna and farmland while 2.23 million ha (53%) of natural vegetation was converted to degraded savanna and farmland in the period 1990–2010. Based on the dynamics recorded during the period 1975–1990 and 1990–2010 respectively, a total of 1.28 million ha (26% of the natural vegetation that was present in 1975) and 1.29 million ha (31% of the natural vegetation that was present in 1990) will be converted to farmland and degraded savanna in the study area by 2050.Thus bowalization will persist and increase in the period up to 2050. The natural vegetation could disappear if protection and restoration measures are not taken. It is thus important to take measures to stop the degradation and to implement programs to restore soils on bowé based on the soil and water conservation techniques used on highly degraded West African soils, such as zaï pit and stone rows with grass strips. Some native plants species adapted to bowalization and resistant to climate change in northern Benin (e.g. Asparagus africanus, Andropogon pseudapricus and Combretum nigricans) should be used in association with soil and water conservation techniques on bowé.     

论退耕的分类

依据不同的标准,退耕可以分为不同的类别。按退耕的主要目的分,可分为生态退耕和非生态退耕;按耕地退耕后的利用方式划分,可划分为退耕还林、退耕还草和退耕还湖以及退耕后林草结合、灌草结合等结合类型;按退耕过程中人工干预程度的大小,又可以划分以人工恢复植被为主的退耕和以自然恢复植被为主的退耕两大类。并特别以耕地退耕前的存在状态或所处位置作为分类标准,重点对坡耕地退耕、沙漠化耕地的退耕、盐碱化耕地的退耕、生态重点区域耕地的退耕以及风景名胜区耕地的退耕的意义和作用作了较为细致的阐述和分析。     

Effect of land-use change on soil fertility characteristics within water-stable aggregates of two cultivated soils in northern Iran

Forest and pastureland soils in highland of northern Iran are being seriously degraded and destructed due to extensive agricultural activities. These land use changes are usually accompanied by decreasing in concentrations of soil organic carbon and nutrients and also deterioration of soil structure in these regions. However, studies on concentration of nutrients and carbohydrates in soils suggest that the location of nutrients within aggregates of each size should be determined. This study was to evaluate the nutrient elements and carbohydrate distributions within water-stable aggregates (WSA) of virgin forest and pasture lands under different land uses in Alborz maintain range, northern Iran. In September 2006, soil samples were collected from depths of 0–20 cm in Typic Haploxerolls soils. The overall pattern indicated that the mean weight diameter (MWD) and WSA were greater in the virgin pasture and forest soils compared with the adjacent cultivated (ex-forest and ex-pasture) soils and aggregates of >1.0 mm size were dominant in the virgin soils, whereas the cultivated soils comprised aggregates of the size ≤0.5 mm. Distribution of organic carbon, nitrogen, phosphorus and carbohydrates within the WSA showed preferential enrichment of these parameters in the macroaggregate fraction (4.75–1.0 mm) for the virgin soils and microaggregate fraction (>0.25 mm) for the exposed soils. Cultivation decreased the concentration of carbohydrates by 23.6% and 20.6% in ex-forest and ex-pasture lands, respectively. Average distribution of total exchangeable bases within WSA showed that the cultivation of forest and pasture soils significantly led to reduce in these nutrient in the 4.75–2.0 mm fraction and increase in concentration of these exchangeable cations in <0.25 mm fractions. In general, results indicated that cultivation significantly led to 71% and 6% reductions in total exchangeable bases within the 4.75–2.0 and <0.25 mm aggregate fraction, respectively, for virgin soil. Since smaller aggregates are preferentially removed by erosion, this study emphasizes the need for sustainable soil management practices that they will minimize nutrient loss when forest or pastures lands are converted to croplands.     

基于DNDC的茶园土壤碳素空间分异及其影响因素——以福建省安溪县为例

[目的]通过探究福建省安溪县茶园土壤碳素储量,揭示各碳素指标的空间分异特征及其关键影响因子,有助于为减少茶园温室气体排放和建设生态茶园提供决策支撑。[方法]文章运用反硝化分解（denitrification decomposition, DNDC）模型和空间统计分析方法对茶园土壤碳素进行模拟和研究。[结果]（1）经过参数率定的DNDC模型对茶园土壤碳素动态循环的模拟具有较好的适用性;（2）安溪茶园土壤有机碳含量丰富,土壤肥力较好。凋落物输入碳是茶园土壤碳素输入的主要来源,平均输入量为505.52 kg/hm2,而通过呼吸作用转化为CO2排放是茶园土壤碳素输出的重要途径,平均CO2排放量为883.78 kg/hm2;(3)茶园SOC10～20cm量、凋落物输入碳量、CH4排放量、CO2排放量均呈现空间聚集分布特征,主要分布在安溪县西部的低山与中低山地区;（4）初始土壤属性中黏粒含量和土壤有机碳含量是影响安溪县茶园土壤碳素空间分异的关键因子,其中土壤黏粒含量对茶园土壤CO2排放量和CH4排放量的影响最强且负向作用效果明显。[结论]安溪县西部等低山和中低山区域土壤肥力较好,但亦应谨慎对待该区...     

The Impact of Pillar II Funding: Validation from a Modelling and Evaluation Perspective

We extend the Common Agricultural Policy Regionalised Impact Modelling System (CAPRI) with a regional computational general equilibrium (CGE) model to estimate the effects of the Pillar II of the Common Agricultural Policy. Our aim is to assess the modeling approach by comparing the scenario results with observations from the evaluation reports for rural development, supplemented with expert interviews and findings from the literature. For this purpose, an ex‐post scenario is developed for Germany that models the effect of the Pillar II measures in 2006. We observe a moderate impact, namely, an increase in agricultural income (5%) and agricultural land use (0.15%), particularly grassland, and a substitution of arable land with grassland. This effect leads to a total increase in agricultural production, particularly of beef, and to an increase in total greenhouse gas emissions and total nitrogen surplus for Germany. Greenhouse gas emissions and nutrient surpluses per ha, however, are reduced. We observe that farm investment programmes displace private investment. The evaluation reports confirm the moderate impact and our major results, as does the comparison with other literature. However, the conclusions about agri‐environment measures and their impact on income differ. The most important difference between our results and the evaluation reports and majority of the present literature is that we also quantify the joint effect between the whole economy and policy measures, with some contradictory effects.     

Exploring land use changes and the role of palm oil production in Indonesia and Malaysia

This study compiles and analyses national-level data on land use change (LUC) and its causes in Indonesia and Malaysia over the past 30 years. The study also explores the role that palm oil has played in past LUC and that projected growth in palm oil production may play in LUC until 2020 and suggests strategies to minimize negative effects. Data collection for the study revealed that the quality and quantity of data on LUC on a national scale over time are low. Despite these uncertainties, the overview of past LUC indicates that large changes in land use have occurred in Indonesia and Malaysia. In Indonesia, LUC can primarily be characterized by forest cover loss on 40 million ha (Mha) of land, a 30% reduction in forest land. Deforestation in Malaysia has been smaller in both absolute and relative terms, with a forest cover loss of nearly 5 Mha (20% reduction in forest land). Other large changes in Malaysia occurred in permanent cropland (excluding oil palm), which has decreased rapidly since the early 1990s, and in land under oil palm cultivation, which experienced a sharp increase. Projections of additional land demand for palm oil production in 2020 range from 1 to 28 Mha in Indonesia. The demand can be met to a large extent by degraded land if no further deforestation is assumed. In Malaysia, expansion projections range from 0.06 to 5 Mha, but only the lowest projection of oil palm expansion is feasible when only degraded land may be used. The role of palm oil production in future LUC depends on the size of the projected expansion as well as agricultural management factors such as implementation of best management practices, earlier replanting with higher yielding plants, and establishment of new plantations on degraded land. The current use of degraded land needs to be investigated in order to reduce possible indirect LUC, land tenure conflicts, or other social impacts. In addition to minimizing direct and indirect LUC by the palm oil sector, measures that reduce deforestation triggered by other causes must also be implemented. A key element for doing so is better planning and governance of land use, which entails more appropriate demarcation of forest land and protection of land that still has forest cover, improved monitoring of land use, and more research to uncover the complexities and dynamics of the causes and drivers of LUC.     

土地整治项目对渭北台塬区土壤理化特性的影响

为探究土地整治项目对土壤理化特性的改良效果,本文以宝鸡市陇县河北镇兰家堡村荒草地整治项目为例,对工程实施前、实施后耕作层土壤结构和理化特性的变化进行了分析。结果表明,土地平整工程对耕作层土壤质量的改善具有显著促进作用。通过开展土地平整工程,土壤pH值显著降低,土壤耕作层土壤pH值较工程实施前降低了3.81%。整个土壤耕作层0~30cm土层深度范围内黏粒含量较整治前提高了36.34%,0~30cm土层深度范围内砂粒含量较整治前降低了5.87%。工程实施对土壤全氮、有效磷、速效钾以及有机质含量均产生了不同程度的影响,土壤全氮含量较工程实施前提高了51.16%,土壤有效磷和速效钾在工程实施后分别较之前提高了53.0%和22.97%,有机质含量较之前高出47.72%。     

Methodology to calculate the carbon footprint of household land use in the urban planning stage

The growing concerns of climate change require implementing measures to quantify, to monitor and to minimize greenhouse gas (GHG) emissions. Nonetheless, most of the measures available are not easy to define or execute because they rely on current emissions and have a corrective character. To address this issue, a methodology to characterize GHG emissions that allows implementing preventive measures is proposed in this paper. The methodology is related to household urban planning procedures and considers urban infrastructures to characterize GHG emissions and to execute preventive measures based on sustainability design criteria. The methodology has been tested by applying it to a set of medium-sized municipalities with average GHG emissions from 6,822.32 kgCO_2eq/year to 5,913.79 kgCO_2eq/year for every residential unit. The results indicate that the greatest pollutant source is transport, especially in the issuance of street network design, followed by gas and electricity consumption. The average undevelopable land area required for the complete GHG emissions capture amounts to 3.42 m² of undevelopable land for every m² of urbanizable land and 9.02 m² of undevelopable land for every m² of built land.     

Afforestation in India: Policy and strategy reforms

Although satellite pictures of forest cover in India have shown the severity of deforestation, little has been done to stop the problem. An analysis of the existing situation and possible policy interventions indicates that deforestation will continue if only marginal changes are introduced. Unless comprehensive policy and strategy reforms are implemented, farming capability and soil systems will be irreversibly degraded. There is a need for both drastic structural change and organizational reform in land use mangement for existing land, and a package of measures to recover degraded land and reduce land use conflicts.     

江西省不同农业土地利用方式对土壤有机碳的影响

研究目的:研究江西省不同农业土地利用方式下的土壤有机碳含量。研究方法:实地土壤样品采集分析与第二次土壤普查资料相结合、GIS空间插值与比较分析相结合的综合研究方法。研究结果:江西省农业土地利用方式和土壤类型不同,土壤有机碳含量存在较大差异;在农业土地利用方式下表层土壤有机碳含量一般为:菜地稻田有林地旱地土壤荒草地;从第一次土壤普查到2008年稻田土壤有机碳含量逐步提高,而且所有农业土地利用方式下土壤有机碳含量均随土壤深度增加而减少。研究结论:通过农业土地利用管理和土壤管理措施的调整,可以增加土壤有机碳的贮量,提高农田有机碳稳定性,减缓大气中CO2浓度增加。     

富锦市不稳定耕地调查与处理对策

划分不稳定耕地类型,并调查其分布及规模,可以为耕地管理及区域农业发展提供依据.该文根据黑龙江省第二次土地调查的实际情况,将不稳定耕地划分为滩地、速生丰产林熟化地、林区多种经营地、开垦草原地、开垦荒地、开垦沼泽地、盐碱化地、高寒低温地、超坡地、其他耕地等10种类型.经调查,富锦市包含6类不稳定耕地,总面积1.979 1万hm2,全部分布于市属集体土地内,国有农场内没有不稳定耕地.根据富锦市不稳地耕地现状及利用中存在的问题,提出了处理对策.     

The carbon footprints of food crop production

The agriculture sector contributes significantly to global carbon emissions from diverse sources such as product and machinery manufacture, transport of materials and direct and indirect soil greenhouse gas emissions. In this article, we use farm survey data from the east of Scotland combined with published estimates of emissions for individual farm operations to quantify the relative contribution of a range of farming operations and determine the carbon footprint of different crops (e.g. legumes, winter and spring cereals, oilseed rape, potato) and farming practices (conventional, integrated and organic). Over all crops and farm types, 75% of the total emissions result from nitrogen fertilizer use (both organic and inorganic)—from production, application, and direct nitrous oxide emissions from the soil resulting from application. Once nitrogen is accounted for, there are no major differences between organic, integrated or conventional farming practices. These data highlight opportunities for carbon mitigation and will be of value for inclusion in full life cycle analyses of arable production systems and in calculations of greenhouse gas balance associated with land-use change.     

生态退耕背景下黄河流域耕地变化与农业生产和生态环境关系研究

[目的]分析生态退耕背景下黄河流域耕地的时空变化特征,探讨黄河流域不同区域耕地变化与农业生产和生态环境的相互关系,旨在为黄河流域农业绿色发展和耕地利用政策提供借鉴。[方法]文章基于2000—2020年黄河流域连续土地利用数据,利用面板格兰杰因果检验和双变量空间自相关量化耕地变化与农业生产、生态环境之间的动态因果及空间交互关系。[结果](1) 2000—2020年黄河流域年均减少耕地69.53万hm²,还林还草是耕地主要减少去向,2020年和2004年是退耕还林还草高峰年,中上游是退耕还林还草重点区;(2)从格兰杰因果检验来看,下游地区退耕还林还草对农业生产和生态环境没有显著影响,上游地区长期退耕还林还草对农业产值增加有利,中游粮食产量和生态系统服务供给低的地区退耕还林还草更多,中上游生态退耕对生态环境有显著促进作用;(3)从空间自相关结果来看,下游地区退耕与农业生产和生态环境的空间分布不具有一致性,黄土高原南部和太行山附近退耕还林还草与生态环境指标呈高—高集聚,鄂尔多斯高原地区退耕与农业产值呈小范围高—高集聚。[结论]退耕还林还草是黄河流域耕地变化的重要原因,退耕...