Relationship Between Soil and Water Conservation Practices and Soil Conditions in Low Mountain and Hilly Region of Northeast China

The soil and water conservation practices of ecological restoration(ER),fish scale pit(FP),furrow and ridge tillage across the slope(FR),shrub strips(SS),and vegetation-covered ridge(VR)are characteristic of the Jixing small watershed of the low mountain and hilly region of Jilin Province,Northeast China.This study aims to elucidate the effects of soil and water conservation practices on soil conditions after the short-term implementation of practices.Soil samples were collected from five soil and water conservation sites(ER,FP,FR,SS,and VR)and two controls(BL and CT)to investigate their properties.To evaluate the influence of soil and water conservation practices on soil quality,an integrated quantitative index,soil quality index(QI),was developed to compare the soil quality under the different soil and water conservation practices.The results show that not all soil and water conservation practices can improve the soil conditions and not all soil properties,especially soil organic carbon(SOC),can be recovered under soil and water conservation practice in short-term.Moreover,the QI in the five soil and water conservation practices and two controls was in the following order:ER>VR>BL>FR>CT>SS>FP.ER exhibited a higher soil quality value on a slope scale.In the low mountain and hilly region of Northeast China,ER is a better choice than the conversion of farmlands to planted grasslands and woodlands early in the soil and water conservation program.

Smallholder Adoption of Soil and Water Conservation Practices in Northern Ghana

Both governmental and non-governmental organizations are engaged in the promotion of soil and water conservation practices in Northern Ghana, but adoption is believed to be low. This study thus examines the determinants of conservation practices adoption by farming households in the area. Data for the study were collected from 445 households located in 15 communities in Northern Ghana. Univariate, bivariate and multivariate probit models were used to analyse the decision to adopt six conservation practices in the area. Results show that the major determinants of adoption are plot and cropping characteristics such as location; and socio-economic and institutional variables such as number of contacts with extension officers, membership in farmer association and distance to major market. A policy implication of the study is the strengthening of extension service in the area to significantly boost conservation adootion.

The Research on the Evaluation and Optimization of the Traditional Dwelling Conservation Practice:A Case Study of Cheng Zhi Hall Restoration Project within Hongcun

Hongcun is the World Cultural Heritage which is a Traditional Village in China,and Cheng Zhi Hall is the most important traditional dwelling within Hongcun.In December 2010,Yi County Cultural Relics Bureau commissioned Anhui Provincial Cultural Relics Protection Center to complete the Restoration Plan of Cheng Zhi Hall,Hongcun Village,Yi County,Huangshan City,Anhui Province,and carried out the actual restoration project from 2015 to 2018.However,by the evaluation of the restoration plan and project of Cheng Zhi Hall,many problems are found such as that the description of restoration measures is rough,the restoration drawings are not clearly marked,and the restoration practices are lack of the theoretical support and so on.Therefore,the aim of this research is to sort out the existing problems,and through the comparative study of the relevant Italian cases,putting forward the optimization strategies of the plan and practice of traditional dwelling conservation practice in China.

Impacts of Field Harvesting and Conservation Practices on the Physical Quality of Yam “Kponan” (Dioscorea cayenensis-rotundata) of Côte D’Ivoire

Yam “Kponan” (Dioscorea cayenensis-rotundata) is a popular staple food in Côte d’Ivoire. However, its rapid decay during conservation prevents regular supply of markets. The objective of this study was therefore to assess the impact of field cultivation and conservation practices on some physical quality parameters of “Kponan”. To this end, “Kponan” yam from three production areas (Bondoukou, Bouna, Kouassi-Kouassikro) was cultivated in each area. At maturity, physical parameters of yams at harvest and after 3 months of storage in field were analyzed. The results showed that injury was the most significant deterioration in yam harvest. The rate of injured yams was highest for hoe-harvested in Kouassi-Kouassikro area (16.67% - 22.22%) regardless of the origin of the cuttings. The main damage observed after the 3 months of storage was rots (22.86% - 60.00%) and weight loss (8.57% - 42.86%). However, yams stored in pits in Bouna zone had less damage (40% - 48.87%) than those stored under straw huts in Bondoukou locality (100%) and at shade under a tree in Kouassi-Kouassikro area (100%). In conclusion, the physical quality of “Kponan” in field is most affected by abusive use of herbicides during weeding and clearing, hoe harvesting and storage in the shade under a tree.

Accommodation of China's Industrial Heritage in Urban Conservation Practices (I)

In recent years, the conservation of industrial heritage in China has gained increasing attention within the broader context of urban conservation practices. For both policy-makers and scholars, accommodating this industrial heritage will emerge as a pertinent issue for consideration as a growing number of industrial architectural legacies dating from the Republican and Maoist eras come under (re)development pressures. This paper thus traces the development of industrial heritage conservation practices in China and discusses several dilemmas intrinsic to this type of conservation, including issues of authenticity, representativeness, and distinction. Based on comparative case studies from China and other international precedents, this paper also seeks to illustrate the different approaches that could be pursued while still attaining a balance between competing interests and claims.

The Nanchang Communication about the potential for implementation of conservation practices for climate change mitigation and adaptation to achieve food security in the 21st century

There is a large number of peer-reviewed publications reporting that a changing climate is one of the biggest challenges humanity will have during the 21st century.With population growth and the need to significantly increase agricultural production per unit of area during the 21st century,a changing climate will put additional stress on soil resources.Soil and water conservation will be key for the future of humanity.Professional societies in the area of agriculture and soil and water conservation have recognized the importance that soil resources will have for humanity during this century and have made calls for implementation of worldwide soil and water conservation.For example,in 2010 the Soil and Water Conservation Society(SWCS)invited a group of scientists to review the literature about the potential to use conservation practices for climate change adaptation and mitigation.The Delgado et al.(2011)paper was used by the SWCS to develop and adopt a position statement about the importance of using soil and water conservation practices to mitigate and adapt to climate change.The International Soil Conservation Organization(ISCO)invited the lead author to present the paper as a keynote presentation at the ISCO 2013 conference.The European Society of Soil Conservation(ESSC)published a short communication about this paper in one of their newsletters in 2014.The World Association of Soil and Water Conservation(WASWAC)also invited the lead author to present a keynote presentation on this topic at the 2015 WASWAC annual meeting in Nanchang.This paper(the Nanchang Communication)is a summary of the Delgado et al.(2011)paper that was used by the SWCS to develop the SWCS position statement related to soil and water conservation and climate change.The Nanchang Communication(this paper)was used by WASWAC to develop a position statement about the immediate need for implementation of conservation practices for mitigation of and adaptation to climate change to achieve food security in the 21st century.These papers(Delgado et al.,2011,Nanchang Communication),and the SWCS and WASWAC position statements,support the conclusions from the worldwide literature that without implementation of soil and water conservation practices for climate change mitigation and adaptation,the survival of life,including our own species,will be in jeopardy,since soils will be key to meeting the higher demands for food during the 21st century.

Accommodation of China's Industrial Heritage in Urban Conservation Practices (Ⅱ)

In recent years, the conservation of industrial heritage in China has gained increasing attention within the broader context of urban conservation practices. For both policy-makers and scholars, accommodating this industrial heritage will emerge as a pertinent issue for consideration as a growing number of industrial architectural legacies dating from the Republican and Maoist eras come under (re)development pressures. This paper thus traces the development of industrial heritage conservation practices in China and discusses several dilemmas intrinsic to this type of conservation, including issues of authenticity, representativeness, and distinction. Based on comparative case studies from China and other international precedents, this paper also seeks to illustrate the different approaches that could be pursued while still attaining a balance between competing interests and claims.

Suppression of weeds and weed seeds in the soil by stubbles and no-tillage in an arid maize-winter wheat-common vetch rotation on the Loess Plateau of China

Reduced tillage provides ecological and economic benefits to arable land on the Loess Plateau of China, where soil erosion has long been a serious problem and soil water availability is largely restricted. However, high abundances of weeds in reduced tillage systems cause significant yield losses. In this study, we explored the effects of no-tillage and stubble retention on the number and density of weeds and weed seeds in a 12-year maize-winter wheat-common vetch rotation on the Loess Plateau. Four treatments including conventional tillage, no-tillage, conventional tillage＋stubble retention and no-tillage＋stubble retention were designed and applied. We found that no-tillage increased the number of weed species and weed density in most of the crops, while stubble retention decreased weed density in maize and tended to suppress weeds in both no-tillage treatments（no-tillage and no-tillage＋stubble retention）. No-tillage led to an increase in the number of weed species in the weed seedbank and tended to increase seed density during the spring growth of winter wheat, but it decreased seed density during post-vetch fallow. Stubble retention tended to reduce seed density during the spring growth of winter wheat and post-vetch fallow. We concluded that no-tillage can promote weeds in the experimental crop rotation, while stubble retention suppresses weeds in untilled fields. The combined effects of stubble retention and no-tillage on weed suppression varied among the three crops. Based on these results, we recommend stubble retention in untilled legume-crop rotations on the Loess Plateau to improve the control of weeds.

Agricultural sustainability in a sensitive environment——a case analysis of Loess Plateau in China

Loess Plateau, an arid and semi arid region in Northwest China, is well known for its most serious soil erosion in terms of sediment yield each year. Soil erosion, which is intensified by agricultural activities, is the major factor influencing sustainable agriculture development in this region. It reduces productivity by removing nutrients and especially reducing water availability that is essential for crop production in the area. It also brings about off site costs by demanding more efforts for maintenance of banks and dams along Yellow River through raising the riverbed with sediment. Climate is capricious and extreme weather conditions occur frequently, which impairs normal agricultural production with erosion and also decrease of water availability. Extensive way of farming still dominates on the Loess Plateau, which cannot produce satisfying economic results and needs to be improved or altered. Conventional agricultural production pattern needs to be reconsidered for husbandry has not been granted its due position. Agriculture is the backbone of economy. Poor agricultural production impedes economic development and vice versa, backward economy also influences the advancement of agriculture. Besides a large population, education status of farmers is another threshold that requires being resolved for a sustainable agriculture. Although conventional agriculture has been practiced there for more than 5000 years, now it cannot meet the demand for food and fiber by the increasing population and some of its farming practices are contributing to environmental degradation directly or indirectly and can sustain no longer. Agriculture on Loess Plateau needs to find its own way of sustainability. To work toward a sustainable agriculture, chances and challenges both indwell on Loess Plateau.

Effectiveness Assessment of Soil Erosion Critical Source Areas for Soil and Water Conservation

Critical source areas （CSAs）, characterized by severe soil erosion and high sediment yield, are considered to have a high priority for conservation. How to identify CSAs and assess the effectiveness of conservation practices is a key issue in site-specific watershed management. The Soil and Water Assessment Tool （SWAT） model is a useful tool for site-specific conservation practices design and several studies have attempted to identify CSAs based on watershed models. However, limited research has reported about the effectiveness of conservation practices targeting CSAs. The aim of this study was to assess the effectiveness of conservation pracrices targeted on CSAs using the SWAT model. CSA was firstly identified based on the 4-year average yearly erosion of each HRU. Appropriate soil conservation practices were then designed for the CSAs. A scenario with conservation practices for the whole watershed was also established as the contrasting counter parts scheme and then compared to the outcome of CSA-targeted conservation practices. The result shows that SWAT can accurately simulate sediment yield in the study area. CSAs were mainly located in slope farmland areas and steep gullies, coinciding with the distribution of land use and slope. The identified CSA covered 20% of the HRUs and contributed on average 44% of sediment yield. Conservation practices targeting CSAs had higher sediment reduction effectiveness （24 115 t km-2 y-1） than conservation practice covering the whole watershed （20 290 t km-2 y-1）. Thus conservation practices targeting CSAs are more effective than broad conservation practices. We conclude that soil conservation practices focusing on CSAs do increase sediment reduction effectiveness. Targeting the placement of soil conservation practices based on the CSAs concept will assist water quality control in watersheds.

How to model the effect of mechanical erosion control practices at a catchment scale?

Conservation agriculture practices are a crucial factor in mitigating and controlling erosion by water.To address water erosion estimates,most environmental models use the USLE,RUSLE,and MUSLE models.Management practices that affect soil erosion by modifying the flow pattern,such as contour farming,strip farming,or terracing,are represented within these models as a support practice(P)factor.However,due to the difficulty in accurately mapping the P-factor,many studies choose to ignore it,using only the default value P-factor 1 which represents the absence of sowing at the level or cultivation in strips.This study proposes a methodology that evaluates the current P-factor based on the angle between the crop row orientation and the elevation contour lines.The method was tested in four areas under soybean crop fields in southern Brazil,totaling 25 km^(2).The reason for choosing four areas is to select different characteristics of rural properties and topographic conditions.The ideal values of the P-factor are expected to be between 0.5 and 0.6;however,in our case,a P-factor greater than 0.8 was obtained in 60%of the area,indicating the low occurrence of contour farming reduces erosion rates.The results show that policymakers could potentially use this methodology(angle between the crop rows and contour lines)to run soil-erosion risk scenarios for a broader application of contour farming.This allows the P-factor to be quantified via a thematic map instead of assigning uniform P-factor values.With a detailed study of the P-factor on the slopes,there is a better understanding of where to target support practices to reduce erosion.

Soil erosion assessment by RUSLE with improved P factor and its validation:Case study on mountainous and hilly areas of Hubei Province,China

The Revised Universal Soil Loss Equation(RUSLE)is widely used to estimate regional soil erosion.However,quantitative impacts of soil and water conservation(SWC)measures on conservation practice factor(P)of the RUSLE remain largely unclear,especially for the mountainous and hilly areas.In this study,we improved the RUSLE by considering quantitative impacts of different SWC measures on the P factor value.The improved RUSLE was validated against the long-term(2000-2015)soil erosion monitoring data obtained from 96 runoff plots(15—35°)in mountainous and hilly areas of Hubei Province,China;the result presented a high accuracy with the determination coefficient of 0.89.Based on the erosion monitoring data of 2018 and 2019,the Root Mean Square Error of the result by the improved RUSLE was 28.0%smaller than that by the original RUSLE with decrement of 19.6%—24.0%in the average P factor values,indicating that the soil erosion modelling accuracy was significantly enhanced by the improved RUSLE.Relatively low P factor values appeared for farmlands with tillage measures(P<0.53),grasslands with engineering measures(P<0.23),woodlands with biological measures(P<0.28),and other land use types with biological measures(P<0.51).The soil erosion modulus showed a downward trend with the corresponding values of 1681.21,1673.14,1594.70,1482.40 and 1437.50 t km^(-2)a-1 in 2000,2005,2010,2015 and 2019,respectively.The applicability of the improved RUSLE was verified by the measurements in typical mountainous and hilly areas of Hubei Province,China,and arrangements of SWC measures of this area were proposed.